v0.11.3

This functionality is similar to `coroutine.yield` and `coroutine.resume` without C restrictions.

.github/FUNDING.yml

@@ -0,0 +1 @@
+github: khvzak

.github/workflows/coverage.yml

@@ -0,0 +1,23 @@
+name: coverage
+on: [push]
+
+jobs:
+  test:
+    name: coverage
+    runs-on: ubuntu-latest
+    container:
+      image: xd009642/tarpaulin:develop-nightly
+      options: --security-opt seccomp=unconfined
+    steps:
+      - name: Checkout repository
+        uses: actions/checkout@main
+
+      - name: Generate coverage report
+        run: |
+          cargo +nightly tarpaulin --verbose --out xml --tests --exclude-files benches/* --exclude-files mlua-sys/src/*/*
+
+      - name: Upload report to codecov.io
+        uses: codecov/codecov-action@v4
+        with:
+          token: ${{secrets.CODECOV_TOKEN}}
+          fail_ci_if_error: false

.github/workflows/main.yml

@@ -7,141 +7,278 @@ jobs:
     runs-on: ${{ matrix.os }}
     strategy:
       matrix:
-        thing:
-        - stable
-        - macos-x86_64
-        - x86_64-msvc
+        os: [ubuntu-latest, macos-latest, windows-latest]
+        rust: [stable]
+        lua: [lua54, lua53, lua52, lua51, luajit, luau, luau-jit, luau-vector4]
         include:
-        - thing: stable
-          target: x86_64-unknown-linux-gnu
-          rust: stable
-          os: ubuntu-latest
-        - thing: macos-x86_64
-          target: x86_64-apple-darwin
-          rust: stable
-          os: macos-latest
-        - thing: x86_64-msvc
-          target: x86_64-pc-windows-msvc
-          rust: stable-x86_64-msvc
-          os: windows-latest
+          - os: ubuntu-latest
+            target: x86_64-unknown-linux-gnu
+          - os: macos-latest
+            target: x86_64-apple-darwin
+          - os: windows-latest
+            target: x86_64-pc-windows-msvc
     steps:
-    - uses: actions/checkout@v1
-    - name: Install Rust (rustup)
-      if: matrix.os != 'macos-latest'
-      run: rustup update ${{ matrix.rust }} --no-self-update && rustup default ${{ matrix.rust }}
-      shell: bash
-    - name: Install Lua (ubuntu)
-      if: matrix.os == 'ubuntu-latest'
-      run: |
-        sudo apt-get update -y
-        sudo apt-get install -y --no-install-recommends liblua5.3-dev liblua5.2-dev liblua5.1-0-dev libluajit-5.1-dev
-    - name: Install Rust (macos)
-      if: matrix.os == 'macos-latest'
-      run: |
-        curl https://sh.rustup.rs | sh -s -- -y
-        echo ::add-path::$HOME/.cargo/bin
-      shell: bash
-    - name: Install GCC (aarch64-linux)
-      run: |
-        sudo apt-get update -y
-        sudo apt-get install -y --no-install-recommends gcc-aarch64-linux-gnu libc6-dev-arm64-cross
-      if: matrix.thing == 'aarch64-linux'
-      shell: bash
-    - run: rustup target add ${{ matrix.target }}
-    - name: Build (Lua 5.3/5.2/5.1 and LuaJIT vendored)
-      run: |
-        for FEATURE in lua53 lua52 lua51 luajit; do
-          echo "Building $FEATURE"
-          cargo build --target ${{ matrix.target }} --release --no-default-features --features "$FEATURE vendored"
-        done
-      shell: bash
-    - name: Build (Lua 5.3/5.2/5.1 and LuaJIT via pkg-config)
-      if: matrix.os == 'ubuntu-latest'
-      run: |
-        for FEATURE in lua53 lua52 lua51 luajit; do
-          echo "Building $FEATURE"
-          cargo build --target ${{ matrix.target }} --release --no-default-features --features $FEATURE
-        done
-      shell: bash
+      - uses: actions/checkout@main
+      - uses: dtolnay/rust-toolchain@stable
+        with:
+          toolchain: ${{ matrix.rust }}
+          target: ${{ matrix.target }}
+      - uses: Swatinem/rust-cache@v2
+      - name: Build ${{ matrix.lua }} vendored
+        run: |
+          cargo build --features "${{ matrix.lua }},vendored"
+          cargo build --features "${{ matrix.lua }},vendored,async,serde,macros,anyhow,userdata-wrappers"
+          cargo build --features "${{ matrix.lua }},vendored,async,serde,macros,anyhow,userdata-wrappers,send"
+        shell: bash
+      - name: Build ${{ matrix.lua }} pkg-config
+        if: ${{ matrix.os == 'ubuntu-latest' }}
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y --no-install-recommends liblua5.4-dev liblua5.3-dev liblua5.2-dev liblua5.1-0-dev libluajit-5.1-dev
+          cargo build --features "${{ matrix.lua }}"
 
-  test_linux:
-    name: Test on Linux
-    runs-on: ubuntu-latest
-    needs: build
-    steps:
-    - uses: actions/checkout@v1
-    - name: Install Rust
-      run: rustup update stable --no-self-update && rustup default stable
-      shell: bash
-    - name: Run tests (Lua 5.3 vendored)
-      run: cargo test --release --no-default-features --features "lua53 vendored"
-      shell: bash
-    - name: Run tests (Lua 5.2 vendored)
-      run: cargo test --release --no-default-features --features "lua52 vendored"
-      shell: bash
-    - name: Run tests (Lua 5.1 vendored)
-      run: cargo test --release --no-default-features --features "lua51 vendored"
-      shell: bash
-    - name: Run tests (LuaJIT vendored)
-      run: cargo test --release --no-default-features --features "luajit vendored"
-      shell: bash
-    - name: Run compile test (Lua 5.3)
-      run: |
-        sudo apt-get update -y
-        sudo apt-get install -y --no-install-recommends liblua5.3-dev
-        cargo test --release --no-default-features --features "lua53 vendored" -- --ignored
-
-  test_macos:
-    name: Test on MacOS
+  build_aarch64_cross_macos:
+    name: Cross-compile to aarch64-apple-darwin
     runs-on: macos-latest
     needs: build
+    strategy:
+      matrix:
+        lua: [lua54, lua53, lua52, lua51, luajit]
     steps:
-    - uses: actions/checkout@v1
-    - name: Install Rust
-      run: |
-        curl https://sh.rustup.rs | sh -s -- -y
-        echo ::add-path::$HOME/.cargo/bin
-      shell: bash
-    - name: Run tests (Lua 5.3 vendored)
-      run: cargo test --release --no-default-features --features "lua53 vendored"
-      shell: bash
-    - name: Run tests (Lua 5.2 vendored)
-      run: cargo test --release --no-default-features --features "lua52 vendored"
-      shell: bash
-    - name: Run tests (Lua 5.1 vendored)
-      run: cargo test --release --no-default-features --features "lua51 vendored"
-      shell: bash
-    - name: Run tests (LuaJIT vendored)
-      run: cargo test --release --no-default-features --features "luajit vendored"
-      shell: bash
+      - uses: actions/checkout@main
+      - uses: dtolnay/rust-toolchain@stable
+        with:
+          toolchain: stable
+          target: aarch64-apple-darwin
+      - name: Cross-compile
+        run: cargo build --target aarch64-apple-darwin --features "${{ matrix.lua }},vendored,async,send,serde,macros,anyhow,userdata-wrappers"
 
-  test_windows:
-    name: Test on Windows
+  build_aarch64_cross_ubuntu:
+    name: Cross-compile to aarch64-unknown-linux-gnu
+    runs-on: ubuntu-latest
+    needs: build
+    strategy:
+      matrix:
+        lua: [lua54, lua53, lua52, lua51, luajit]
+    steps:
+      - uses: actions/checkout@main
+      - uses: dtolnay/rust-toolchain@stable
+        with:
+          toolchain: stable
+          target: aarch64-unknown-linux-gnu
+      - name: Install ARM compiler toolchain
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y --no-install-recommends gcc-aarch64-linux-gnu libc6-dev-arm64-cross
+        shell: bash
+      - name: Cross-compile
+        run: cargo build --target aarch64-unknown-linux-gnu --features "${{ matrix.lua }},vendored,async,send,serde,macros,anyhow,userdata-wrappers"
+        shell: bash
+
+  build_armv7_cross_ubuntu:
+    name: Cross-compile to armv7-unknown-linux-gnueabihf
+    runs-on: ubuntu-latest
+    needs: build
+    strategy:
+      matrix:
+        lua: [lua54, lua53, lua52, lua51]
+    steps:
+      - uses: actions/checkout@main
+      - uses: dtolnay/rust-toolchain@stable
+        with:
+          toolchain: stable
+          target: armv7-unknown-linux-gnueabihf
+      - name: Install ARM compiler toolchain
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y --no-install-recommends gcc-arm-linux-gnueabihf libc-dev-armhf-cross
+        shell: bash
+      - name: Cross-compile
+        run: cargo build --target armv7-unknown-linux-gnueabihf --features "${{ matrix.lua }},vendored,async,send,serde,macros,anyhow,userdata-wrappers"
+        shell: bash
+
+  test:
+    name: Test
+    runs-on: ${{ matrix.os }}
+    needs: build
+    strategy:
+      matrix:
+        os: [ubuntu-latest, macos-latest, windows-latest]
+        rust: [stable, nightly]
+        lua: [lua54, lua53, lua52, lua51, luajit, luajit52, luau, luau-jit, luau-vector4]
+        include:
+          - os: ubuntu-latest
+            target: x86_64-unknown-linux-gnu
+          - os: macos-latest
+            target: x86_64-apple-darwin
+          - os: windows-latest
+            target: x86_64-pc-windows-msvc
+    steps:
+      - uses: actions/checkout@main
+      - uses: dtolnay/rust-toolchain@stable
+        with:
+          toolchain: ${{ matrix.rust }}
+          target: ${{ matrix.target }}
+      - uses: Swatinem/rust-cache@v2
+      - name: Run ${{ matrix.lua }} tests
+        run: |
+          cargo test --features "${{ matrix.lua }},vendored"
+          cargo test --features "${{ matrix.lua }},vendored,async,serde,macros,anyhow,userdata-wrappers"
+          cargo test --features "${{ matrix.lua }},vendored,async,serde,macros,anyhow,userdata-wrappers,send"
+        shell: bash
+      - name: Run compile tests (macos lua54)
+        if: ${{ matrix.os == 'macos-latest' && matrix.lua == 'lua54' }}
+        run: |
+          TRYBUILD=overwrite cargo test --features "${{ matrix.lua }},vendored" --tests -- --ignored
+          TRYBUILD=overwrite cargo test --features "${{ matrix.lua }},vendored,async,send,serde,macros" --tests -- --ignored
+        shell: bash
+
+  test_with_sanitizer:
+    name: Test with address sanitizer
+    runs-on: ${{ matrix.os }}
+    needs: build
+    strategy:
+      matrix:
+        os: [ubuntu-latest]
+        rust: [nightly]
+        lua: [lua54, lua53, lua52, lua51, luajit, luau, luau-jit, luau-vector4]
+        include:
+          - os: ubuntu-latest
+            target: x86_64-unknown-linux-gnu
+    steps:
+      - uses: actions/checkout@main
+      - uses: dtolnay/rust-toolchain@stable
+        with:
+          toolchain: ${{ matrix.rust }}
+          target: ${{ matrix.target }}
+      - uses: Swatinem/rust-cache@v2
+      - name: Run ${{ matrix.lua }} tests with address sanitizer
+        run: |
+          cargo test --tests --features "${{ matrix.lua }},vendored,async,serde,macros,anyhow" --target x86_64-unknown-linux-gnu -- --skip test_too_many_recursions
+          cargo test --tests --features "${{ matrix.lua }},vendored,async,serde,macros,anyhow,userdata-wrappers,send" --target x86_64-unknown-linux-gnu -- --skip test_too_many_recursions
+        shell: bash
+        env:
+          RUSTFLAGS: -Z sanitizer=address
+
+  test_with_memory_limit:
+    name: Test with memory limit
+    runs-on: ${{ matrix.os }}
+    needs: build
+    strategy:
+      matrix:
+        os: [ubuntu-latest]
+        rust: [nightly]
+        lua: [lua54, lua53, lua52, lua51, luajit, luau, luau-jit, luau-vector4]
+        include:
+          - os: ubuntu-latest
+            target: x86_64-unknown-linux-gnu
+    steps:
+      - uses: actions/checkout@main
+      - uses: dtolnay/rust-toolchain@stable
+        with:
+          toolchain: ${{ matrix.rust }}
+          target: ${{ matrix.target }}
+      - uses: Swatinem/rust-cache@v2
+      - name: Run ${{ matrix.lua }} tests with forced memory limit
+        run: |
+          cargo test --tests --features "${{ matrix.lua }},vendored,async,send,serde,macros,anyhow,userdata-wrappers"
+        shell: bash
+        env:
+          RUSTFLAGS: --cfg=force_memory_limit
+
+  test_modules:
+    name: Test modules
+    runs-on: ${{ matrix.os }}
+    needs: build
+    strategy:
+      matrix:
+        os: [ubuntu-latest, macos-latest]
+        rust: [stable]
+        lua: [lua54, lua53, lua52, lua51, luajit]
+        include:
+          - os: ubuntu-latest
+            target: x86_64-unknown-linux-gnu
+          - os: macos-latest
+            target: x86_64-apple-darwin
+    steps:
+      - uses: actions/checkout@main
+      - uses: dtolnay/rust-toolchain@stable
+        with:
+          toolchain: ${{ matrix.rust }}
+          target: ${{ matrix.target }}
+      - uses: Swatinem/rust-cache@v2
+      - name: Run ${{ matrix.lua }} module tests
+        run: |
+          (cd tests/module && cargo build --release --features "${{ matrix.lua }}")
+          (cd tests/module/loader && cargo test --release --features "${{ matrix.lua }},vendored")
+        shell: bash
+
+  test_modules_windows:
+    name: Test modules on Windows
     runs-on: windows-latest
     needs: build
+    strategy:
+      matrix:
+        lua: [lua54, luajit]
+    defaults:
+      run:
+        shell: msys2 {0}
     steps:
-    - uses: actions/checkout@v1
-    - name: Install Rust
-      run: rustup update stable --no-self-update && rustup default stable
-      shell: bash
-    - name: Run tests (Lua 5.3 vendored)
-      run: cargo test --release --no-default-features --features "lua53 vendored"
-      shell: bash
-    - name: Run tests (Lua 5.2 vendored)
-      run: cargo test --release --no-default-features --features "lua52 vendored"
-      shell: bash
-    - name: Run tests (Lua 5.1 vendored)
-      run: cargo test --release --no-default-features --features "lua51 vendored"
-      shell: bash
-    - name: Run tests (LuaJIT vendored)
-      run: cargo test --release --no-default-features --features "luajit vendored"
-      shell: bash
+      - uses: msys2/setup-msys2@v2
+      - uses: actions/checkout@main
+      - name: Install Rust & Lua
+        run: |
+          pacman -S --noconfirm mingw-w64-x86_64-rust mingw-w64-x86_64-lua mingw-w64-x86_64-luajit mingw-w64-x86_64-pkg-config
+      - name: Run ${{ matrix.lua }} module tests
+        run: |
+          (cd tests/module && cargo build --release --features "${{ matrix.lua }}")
+          (cd tests/module/loader && cargo test --release --features "${{ matrix.lua }}")
+
+  test_wasm32_emscripten:
+    name: Test on wasm32-unknown-emscripten
+    runs-on: ubuntu-latest
+    needs: build
+    strategy:
+      matrix:
+        lua: [lua54, lua53, lua52, lua51, luau]
+    steps:
+      - uses: actions/checkout@main
+      - uses: dtolnay/rust-toolchain@stable
+        with:
+          toolchain: stable
+          target: wasm32-unknown-emscripten
+      - name: Install Emscripten
+        run: |
+          sudo apt-get update
+          sudo apt-get install -y --no-install-recommends emscripten
+      - name: Run ${{ matrix.lua }} tests
+        run: |
+          cargo test --tests --features "${{ matrix.lua }},vendored"
+          cargo test --tests --features "${{ matrix.lua }},vendored,async,serde,macros,anyhow,userdata-wrappers"
 
   rustfmt:
     name: Rustfmt
     runs-on: ubuntu-latest
     steps:
-    - uses: actions/checkout@v1
-    - name: Install Rust
-      run: rustup update stable && rustup default stable && rustup component add rustfmt
-    - run: cargo fmt -- --check
+      - uses: actions/checkout@main
+      - uses: dtolnay/rust-toolchain@nightly
+        with:
+          components: rustfmt
+      - run: cargo fmt -- --check
+
+  clippy:
+    name: Clippy
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        lua: [lua54, lua53, lua52, lua51, luajit, luau, luau-jit, luau-vector4]
+    steps:
+      - uses: actions/checkout@main
+      - uses: dtolnay/rust-toolchain@stable
+        with:
+          toolchain: nightly
+          components: clippy
+      - uses: giraffate/clippy-action@v1
+        with:
+          reporter: 'github-pr-review'
+          clippy_flags: --features "${{ matrix.lua }},vendored,async,send,serde,macros,anyhow,userdata-wrappers"

.github/workflows/typos.yml

@@ -0,0 +1,17 @@
+name: Typos Check
+on:
+  pull_request:
+  workflow_dispatch:
+
+jobs:
+  run:
+    name: Spell Check with Typos
+    runs-on: ubuntu-latest
+    steps:
+    - name: Checkout Actions Repository
+      uses: actions/checkout@v4
+
+    - name: Check spelling
+      uses: crate-ci/typos@master
+      with:
+        config: ./typos.toml

.gitignore

@@ -4,3 +4,4 @@ Cargo.lock
 
 .vscode/
 .DS_Store
+.stignore

CHANGELOG.md

@@ -0,0 +1,623 @@
+## v0.11.3 (Aug 30, 2025)
+
+- Add `Lua::yield_with` to use as `coroutine.yield` functional replacement in async functions for any Lua
+- Do not try to yield at non-yielable points in Luau interrupt (#632)
+- Add `Buffer::cursor` method (Luau)
+- Add `Lua::create_buffer_with_capacity` method (Luau)
+- Make Lua reference values cheap to clone (only increments ref count)
+- Fix panic on large (>67M entries) table creation
+
+## v0.11.2 (Aug 10, 2025)
+
+- Faster stack push for `Variadic<T>`
+- Fix handling Windows paths with drive letter in Luau require (#623)
+- Make Luau registered aliases ascii case-insensitive (#620)
+- Fix deserializing negative zeros `-0.0` (#618)
+
+## v0.11.1 (Jul 15, 2025)
+
+- Fixed bug exhausting Lua auxiliary stack and leaving it without reserve (#615)
+- `Lua::push_c_function` now correctly handles OOM for Lua 5.1 and Luau
+
+## v0.11.0 (Jul 14, 2025)
+
+Changes since v0.11.0-beta.3
+
+- Allow linking external Lua libraries in a build script (e.g. pluto) using `external` mlua-sys feature flag
+- `Lua::inspect_stack` takes a callback with `&Debug` argument, instead of returning `Debug` directly
+- Added `Debug::function` method to get function running at a given level
+- `Debug::curr_line` is deprecated in favour of `Debug::current_line` that returns `Option<usize>`
+- Added `Lua::set_globals` method to replace global environment
+- `Table::set_metatable` now returns `Result<()>` (this operation can fail in sandboxed Luau mode)
+- `impl ToString` replaced with `Into<StdString>`  in `UserData` registration
+- `Value::as_str` and `Value::as_string_lossy` methods are deprecated (as they are non-idiomatic)
+- Bugfixes and improvements
+
+## v0.11.0-beta.3 (Jun 23, 2025)
+
+- Luau in sandboxed mode has reduced options in `collectgarbage` function (to follow the official doc)
+- `Function::deep_clone` now returns `Result<Function>` as this operation can trigger memory errors
+- Luau "Require" resolves included Lua files relative to the current directory (#605)
+- Fixed bug when finalizing `AsyncThread` on drop (`call_async` methods family)
+
+## v0.11.0-beta.2 (Jun 12, 2025)
+
+- Lua 5.4 updated to 5.4.8
+- Terminate Rust `Future` when `AsyncThread` is dropped (without relying on Lua GC)
+- Added `loadstring` function to Luau
+- Make `AsChunk` trait dyn-friendly
+- Luau `Require` trait synced with Luau 0.674
+- Luau `Require` trait methods now can return `Error` variant (in `NavigateError` enum)
+- Added `__type` to `Error`'s userdata metatable (for `typeof` function)
+- `parking_log/send_guard` is moved to `userdata-wrappers` feature flag
+- New `serde` feature flag to replace `serialize` (the old one is still available)
+
+## v0.11.0-beta.1 (May 7th, 2025)
+
+- New "require-by-string" for Luau (with `Require` trait and async support)
+- Added `Thread::resume_error` support for Luau
+- 52 bit integers support for Luau (this is a breaking change)
+- New features for Luau compiler (constants, disabled builtins, known members)
+- `AsyncThread<A, R>` changed to `AsyncThread<R>` (`A` pushed to stack immediately)
+- Lifetime `'a` moved from `AsChunk<'a>` to `AsChunk::source where Self: 'a`
+- `Lua::scope` pass `&Scope` instead of `&mut Scope` to closure
+- Added global hooks support (Lua 5.1+)
+- Added per-thread hooks support (Lua 5.1+)
+- `Lua::init_from_ptr` renamed to `Lua::get_or_init_from_ptr` and returns `&Lua`
+- `Lua:load_from_function` is deprecated (this is `register_module` now)
+- Added `Lua::register_module` and `Lua::preload_module`
+
+## v0.10.4 (May 5th, 2025)
+
+- Luau updated to 0.672
+- New serde option `encode_empty_tables_as_array` to serialize empty tables as arrays
+- Added `WeakLua` and `Lua::weak()` to create weak references to Lua state
+- Trigger abort when Luau userdata destructors are panic (Luau GC does not support it)
+- Added `AnyUserData::type_id()` method to get the type id of the userdata
+- Added `Chunk::name()`, `Chunk::environment()` and `Chunk::mode()` functions
+- Support borrowing underlying wrapped types for `UserDataRef` and `UserDataRefMut` (under `userdata-wrappers` feature)
+- Added large (52bit) integers support for Luau
+- Enable `serde` for `bstr` if `serialize` feature flag is enabled
+- Recursive warnings (Lua 5.4) are no longer allowed
+- Implemented `IntoLua`/`FromLua` for `BorrowedString` and `BorrowedBytes`
+- Implemented `IntoLua`/`FromLua` for `char`
+- Enable `Thread::reset()` for all Lua versions (limited support for 5.1-5.3)
+- Bugfixes and improvements
+
+## v0.10.3 (Jan 27th, 2025)
+
+- Set `Default` for `Value` to be `Nil`
+- Allow exhaustive match on `Value` (#502)
+- Add `Table::set_safeenv` method (Luau)
+
+## v0.10.2 (Dec 1st, 2024)
+
+- Switch proc-macro-error to proc-macro-error2 (#493)
+- Do not allow Lua to run GC finalizers on ref thread (#491)
+- Fix chunks loading in Luau when memory limit is enforced (#488)
+- Added `String::wrap` method to wrap arbitrary `AsRef<[u8]>` into `impl IntoLua`
+- Better FreeBSD/OpenBSD support (thanks to cos)
+- Delay "any" userdata metatable creation until first instance is created (#482)
+- Reduce amount of generated code for `UserData` (less generics)
+
+## v0.10.1 (Nov 9th, 2024)
+
+- Minimal Luau updated to 0.650
+- Added Luau native vector library support (this can change behavior if you use `vector` function!)
+- Added Lua `String::display` method
+- Improved pretty-printing for Lua tables (#478)
+- Added `Scope::create_any_userdata` to create Lua objects from any non-`'static` Rust types
+- Added `AnyUserData::destroy` method
+- New `userdata-wrappers` feature to `impl UserData` for `Rc<T>`/`Arc<T>`/`Rc<RefCell<T>>`/`Arc<Mutex<T>>` (similar to v0.9)
+- `UserDataRef` in `send` mode now uses shared lock if `T: Sync` (and exclusive lock otherwise)
+- Added `Scope::add_destructor` to attach custom destructors
+- Added `Lua::try_app_data_ref` and `Lua::try_app_data_mut` methods
+- Added `From<Vec>` and `Into<Vec>` support to `MultiValue` and `Variadic` types
+- Bug fixes and improvements (#477 #479)
+
+## v0.10.0 (Oct 25th, 2024)
+
+Changes since v0.10.0-rc.1
+
+- Added `error-send` feature flag (disabled by default) to require `Send + Sync` for `Error`
+- Some performance improvements
+
+## v0.10.0-rc.1
+
+- `Lua::scope` is back
+- Support yielding from hooks for Lua 5.3+
+- Support setting metatable for Lua builtin types (number/string/function/etc)
+- Added `LuaNativeFn`/`LuaNativeFnMut`/`LuaNativeAsyncFn` traits for using in `Function::wrap`
+- Added `Error::chain` method to return iterator over nested errors
+- Added `Lua::exec_raw` helper to execute low-level Lua C API code
+- Added `Either<L, R>` enum to combine two types into a single one
+- Added a new `Buffer` type for Luau
+- Added `Value::is_error` and `Value::as_error` helpers
+- Added `Value::Other` variant to represent unknown Lua types (eg LuaJIT CDATA)
+- Added (optional) `anyhow` feature to implement `IntoLua` for `anyhow::Error`
+- Added `IntoLua`/`FromLua` for `OsString`/`OsStr` and `PathBuf`/`Path`
+
+## v0.10.0-beta.2
+
+- Updated `ThreadStatus` enum to include `Running` and `Finished` variants.
+- `Error::CoroutineInactive` renamed to `Error::CoroutineUnresumable`.
+- `IntoLua`/`IntoLuaMulti` now uses `impl trait` syntax for args (shorten from `a.get::<_, T>` to `a.get::<T>`).
+- Removed undocumented `Lua::into_static`/`from_static` methods.
+- Futures now require `Send` bound if `send` feature is enabled.
+- Dropped lifetime from `UserDataMethods` and `UserDataFields` traits.
+- `Compiler::compile()` now returns `Result` (Luau).
+- Removed `Clone` requirement from `UserDataFields::add_field()`.
+- `TableExt` and `AnyUserDataExt` traits were combined into `ObjectLike` trait.
+- Disabled `send` feature in module mode (since we don't have exclusive access to Lua).
+- `Chunk::set_environment()` takes `Table` instead of `IntoLua` type.
+- Reduced the compile time contribution of `next_key_seed` and `next_value_seed`.
+- Reduced the compile time contribution of `serde_userdata`.
+- Performance improvements.
+
+## v0.10.0-beta.1
+
+- Dropped `'lua` lifetime (subtypes now store a weak reference to Lua)
+- Removed (experimental) owned types (they no longer needed)
+- Make Lua types truly `Send` and `Sync` (when enabling `send` feature flag)
+- Removed `UserData` impl for Rc/Arc types ("any" userdata functions can be used instead)
+- `Lua::replace_registry_value` takes `&mut RegistryKey`
+- `Lua::scope` temporary disabled (will be re-added in the next release)
+
+## v0.9.9
+
+- Minimal Luau updated to 0.629
+- Fixed bug when attempting to reset or resume already running coroutines (#416).
+- Added `RegistryKey::id()` method to get the underlying Lua registry key id.
+
+## v0.9.8
+
+- Fixed serializing same table multiple times (#408)
+- Use `mlua-sys` v0.6 (to support Luau 0.624+)
+- Fixed cross compilation of windows dlls from unix (#394)
+
+## v0.9.7
+
+- Implemented `IntoLua` for `RegistryKey`
+- Mark `__idiv` metamethod as available for luau
+- Added `Function::deep_clone()` method (Luau)
+- Added `SerializeOptions::detect_serde_json_arbitrary_precision` option
+- Added `Lua::create_buffer()` method (Luau)
+- Support serializing buffer type as a byte slice (Luau)
+- Perf: Implemented `push_into_stack`/`from_stack` for `Option<T>`
+- Added `Lua::create_ser_any_userdata()` method
+
+## v0.9.6
+
+- Added `to_pointer` function to `Function`/`Table`/`Thread`
+- Implemented `IntoLua` for `&Value`
+- Implemented `FromLua` for `RegistryKey`
+- Faster (~5%) table array traversal during serialization
+- Some performance improvements for bool/int types
+
+## v0.9.5
+
+- Minimal Luau updated to 0.609
+- Luau max stack size increased to 1M (from 100K)
+- Implemented `IntoLua` for refs to `String`/`Table`/`Function`/`AnyUserData`/`Thread` + `RegistryKey`
+- Implemented `IntoLua` and `FromLua` for `OwnedThread`/`OwnedString`
+- Fixed `FromLua` derive proc macro to cover more cases
+
+## v0.9.4
+
+- Fixed loading all-in-one modules under mixed states (eg. main state and coroutines)
+
+## v0.9.3
+
+- WebAssembly support (`wasm32-unknown-emscripten` target)
+- Performance improvements (faster Lua function calls for lua51/jit/luau)
+
+## v0.9.2
+
+- Added binary modules support to Luau
+- Added Luau package module (uses `StdLib::PACKAGE`) with loaders (follows lua5.1 interface)
+- Added support of Luau 0.601+ buffer type (represented as userdata in Rust)
+- LuaJIT `cdata` type is also represented as userdata in Rust (instead of panic)
+- Vendored LuaJIT switched to rolling vanilla (from openresty)
+- Added `Table::for_each` method for fast table pairs traversal (faster than `pairs`)
+- Performance improvements around table traversal (and faster serialization)
+- Bug fixes and improvements
+
+## v0.9.1
+
+- impl Default for Lua
+- impl IntoLuaMulti for `std::result::Result<(), E>`
+- Fix using wrong userdata index after processing Variadic args (#311)
+
+## v0.9.0
+
+Changes since v0.9.0-rc.3
+
+- Improved non-static (scoped) userdata support
+- Added `Scope::create_any_userdata()` method
+- Added `Lua::set_vector_metatable()` method (`unstable` feature flag)
+- Added `OwnedThread` type (`unstable` feature flag)
+- Minimal Luau updated to 0.590
+- Added new option `sort_keys` to `DeserializeOptions` (`Lua::from_value()` method)
+- Changed `Table::raw_len()` output type to `usize`
+- Helper functions for `Value` (eg: `Value::as_number()`/`Value::as_string`/etc)
+- Performance improvements
+
+## v0.9.0-rc.3
+
+- Minimal Luau updated to 0.588
+
+## v0.9.0-rc.2
+
+- Added `#[derive(FromLua)]` macro to opt-in into `FromLua<T> where T: 'static + Clone` (userdata type).
+- Support vendored module mode for windows (raw-dylib linking, Rust 1.71+)
+- `module` and `vendored` features are now mutually exclusive
+- Use `C-unwind` ABI (Rust 1.71+)
+- Changed `AsChunk` trait to support capturing wrapped Lua types
+
+## v0.9.0-rc.1
+
+- `UserDataMethods::add_async_method()` takes `&T` instead of cloning `T`
+- Implemented `PartialEq<[T]>` for tables
+- Added Luau 4-dimensional vectors support (`luau-vector4` feature)
+- `Table::sequence_values()` iterator no longer uses any metamethods (`Table::raw_sequence_values()` is deprecated)
+- Added `Table:is_empty()` function that checks both hash and array parts
+- Refactored Debug interface
+- Re-exported `ffi` (`mlua-sys`) crate for easier writing of unsafe code
+- Refactored Lua 5.4 warnings interface
+- Take `&str` as function name in `TableExt` and `AnyUserDataExt` traits
+- Added module attribule `skip_memory_check` to improve performance
+- Added `AnyUserData::wrap()` to provide more easy way of creating _any_ userdata in Lua
+
+## v0.9.0-beta.3
+
+- Added `OwnedAnyUserData::take()`
+- Switch to `DeserializeOwned`
+- Overwrite error context when called multiple times
+- New feature flag `luau-jit` to enable (experimental) Luau codegen backend
+- Set `__name` field in userdata metatable
+- Added `Value::to_string()` method similar to `luaL_tolstring`
+- Lua 5.4.6
+- Application data container now allows to mutably and immutably borrow different types at the same time
+- Performance optimizations
+- Support getting and setting environment for Lua functions.
+- Added `UserDataFields::add_field()` method to add static fields to UserData
+
+Breaking changes:
+- Require environment to be a `Table` instead of `Value` in Chunks.
+- `AsChunk::env()` renamed to `AsChunk::environment()`
+
+## v0.9.0-beta.2
+
+New features:
+- Added `Thread::set_hook()` function to set hook on threads
+- Added pretty print to the Debug formatting to Lua `Value` and `Table`
+- ffi layer moved to `mlua-sys` crate
+- Added OwnedString (unstable)
+
+Breaking changes:
+- Refactor `HookTriggers` (make it const)
+
+## v0.9.0-beta.1
+
+New features:
+- Owned Lua types (unstable feature flag)
+- New functions `Function::wrap`/`Function::wrap_mut`/`Function::wrap_async`
+- `Lua::register_userdata_type()` to register a custom userdata types (without requiring `UserData` trait)
+- `Lua::create_any_userdata()`
+- Added `create_userdata_ref`/`create_userdata_ref_mut` for scopes
+- Added `AnyUserDataExt` trait with auxiliary functions for `AnyUserData`
+- Added `UserDataRef` and `UserDataRefMut` type wrapped that implement `FromLua`
+- Improved error handling:
+  * Improved error reporting when calling Rust functions from Lua.
+  * Added `Error::BadArgument` to help identify bad argument position or name
+  * Added `ErrorContext` extension trait to attach additional context to `Error`
+
+Breaking changes:
+- Refactored `AsChunk` trait
+- `ToLua`/`ToLuaMulti` renamed to `IntoLua`/`IntoLuaMulti`
+- Renamed `to_lua_err` to `into_lua_err`
+- Removed `FromLua` impl for `T: UserData+Clone`
+- Removed `Lua::async_scope`
+- Added `&Lua` arg to Luau interrupt callback
+
+Other:
+- Better Debug for String
+- Allow deserializing values from serializable UserData using `Lua::from_value()` method
+- Added `Table::clear()` method
+- Added `Error::downcast_ref()` method
+- Support setting memory limit for Lua 5.1/JIT/Luau
+- Support setting module name in `#[lua_module(name = "...")]` macro
+- Minor fixes and improvements
+
+## v0.8.10
+
+- Update to Luau 0.590 (luau0-src to 0.7.x)
+- Fix loading luau code starting with \t
+- Pin lua-src and luajit-src versions
+
+## v0.8.9
+
+- Update minimal (vendored) Lua 5.4 to 5.4.6
+- Use `lua_closethread` instead of `lua_resetthread` in vendored mode (Lua 5.4.6)
+- Allow deserializing Lua null into unit (`()`) or unit struct.
+
+## v0.8.8
+
+- Fix potential deadlock when trying to reuse dropped registry keys.
+- Optimize userdata methods call when __index and fields_getters are nil
+
+## v0.8.7
+
+- Minimum Luau updated to 0.555 (`LUAI_MAXCSTACK` limit increased to 100000)
+- `_VERSION` in Luau now includes version number
+- Fixed lifetime of `DebugNames` in `Debug::names()` and `DebugSource` in `Debug::source()`
+- Fixed subtraction overflow when calculating index for `MultiValue::get()`
+
+## v0.8.6
+
+- Fixed bug when recycled Registry slot can be set to Nil
+
+## v0.8.5
+
+- Fixed potential unsoundness when using `Layout::from_size_align_unchecked` and Rust 1.65+
+- Performance optimizations around string and table creation in standalone mode
+- Added fast track path to Table `get`/`set`/`len` methods without metatable
+- Added new methods `push`/`pop`/`raw_push`/`raw_pop` to Table
+- Fix getting caller information from `Lua::load`
+- Better checks and tests when trying to modify a Luau readonly table
+
+## v0.8.4
+
+- Minimal Luau updated to 0.548
+
+## v0.8.3
+
+- Close to-be-closed variables for Lua 5.4 when using call_async functions (#192)
+- Fixed Lua assertion when inspecting another thread stack. (#195)
+- Use more reliable way to create LuaJIT VM (which can fail if use Rust allocator on non-x86 platforms)
+
+## v0.8.2
+
+- Performance optimizations in handling UserData
+- Minimal Luau updated to 0.536
+- Fixed bug in `Function::bind` when passing empty binds and no arguments (#189)
+
+## v0.8.1
+
+- Added `Lua::create_proxy` for accessing to UserData static fields and functions without instance
+- Added `Table::to_pointer()` and `String::to_pointer()` functions
+- Bugfixes and improvements (#176 #179)
+
+## v0.8.0
+Changes since 0.7.4
+- Luau support
+- Removed C glue
+- Added async support to `__index` and `__newindex` metamethods
+- Added `Function::info()` to get information about functions (#149).
+- Added `parking_lot` dependency under feature flag (for `UserData`)
+- `Hash` implementation for Lua String
+- Added `Value::to_pointer()` function
+- Performance improvements
+
+Breaking changes:
+- Refactored `AsChunk` trait (added implementation for `Path` and `PathBuf`).
+
+## v0.8.0-beta.5
+
+- Lua sources no longer needed to build modules
+- Added `__iter` metamethod for Luau
+- Added `Value::to_pointer()` function
+- Added `Function::coverage` for Luau to obtain coverage report
+- Bugfixes and improvements (#153 #161 #168)
+
+## v0.8.0-beta.4
+
+- Removed `&Lua` from `Lua::set_interrupt` as it's not safe (introduced in v0.8.0-beta.3)
+- Enabled `Lua::gc_inc` for Luau
+- Luau `debug` module marked as safe (enabled by default)
+- Implemented `Hash` for Lua String
+- Support mode options in `collectgarbage` for Luau
+- Added ability to set global Luau compiler (used for loading all chunks).
+- Refactored `AsChunk` trait (breaking changes).
+  `AsChunk` now implemented for `Path` and `PathBuf` to load lua files from fs.
+- Added `parking_lot` dependency and feature flag (for `UserData`)
+- Added `Function::info()` to get information about functions (#149).
+- Bugfixes and improvements (#104 #142)
+
+## v0.8.0-beta.3
+
+- Luau vector constructor
+- Luau sandboxing support
+- Luau interrupts (yieldable)
+- More Luau compiler options (mutable globals)
+- Other performance improvements
+
+## v0.8.0-beta.2
+
+- Luau vector datatype support
+- Luau readonly table attribute
+- Other Luau improvements
+
+## v0.8.0-beta.1
+
+- Luau support
+- Refactored ffi module. C glue is no longer required
+- Added async support to `__index` and `__newindex` metamethods
+
+## v0.7.4
+
+- Improved `Lua::create_registry_value` to reuse previously expired registry keys.
+  No need to call `Lua::expire_registry_values` when creating/dropping registry values.
+- Added `Lua::replace_registry_value` to change value of an existing Registry Key
+- Async calls optimization
+
+## v0.7.3
+
+- Fixed cross-compilation issue (introduced in 84a174c)
+
+## v0.7.2
+
+- Allow `pkg-config` to omit include paths if they equals to standard (#114).
+- Various bugfixes (eg. #121)
+
+## v0.7.1
+
+- Fixed traceback generation for errors (#112)
+- `Lua::into_static/from_static` methods have been removed from the docs and are discouraged for use
+
+## v0.7.0
+
+- New "application data" api to store arbitrary objects inside Lua
+- New feature flag `luajit52` to build/support LuaJIT with partial compatibility with Lua 5.2
+- Added async meta methods for all Lua (except 5.1)
+- Added `AnyUserData::take()` to take UserData objects from Lua
+- Added `set_nth_user_value`/`get_nth_user_value` to `AnyUserData` for all Lua versions
+- Added `set_named_user_value`/`get_named_user_value` to `AnyUserData` for all Lua versions
+- Added `Lua::inspect_stack()` to get information about the interpreter runtime stack
+- Added `set_warning_function`/`remove_warning_function`/`warning` functions to `Lua` for 5.4
+- Added `TableExt::call()` to call tables with `__call` metamethod as functions
+- Added `Lua::unload()` to unload modules
+- `ToLua` implementation for arrays changed to const generics
+- Added thread (coroutine) cache for async execution (disabled by default and works for Lua 5.4/JIT)
+- LuaOptions and (De)SerializeOptions marked as const
+- Fixed recursive tables serialization when using `serde::Serialize` for Lua Tables
+- Improved errors reporting. Now source included to `fmt::Display` implementation for `Error::CallbackError`
+- Major performance improvements
+
+## v0.6.6
+
+- Fixed calculating `LUA_REGISTRYINDEX` when cross-compiling for lua51/jit (#82)
+- Updated documentation & examples
+
+## v0.6.5
+
+- Fixed bug when polling async futures (#77)
+- Refactor Waker handling in async code (+10% performance gain when calling async functions)
+- Added `Location::caller()` information to `Lua::load()` if chunk's name is None (Rust 1.46+)
+- Added serialization of i128/u128 types (serde)
+
+## v0.6.4
+
+- Performance optimizations
+- Fixed table traversal used in recursion detection in deserializer
+
+## v0.6.3
+
+- Disabled catching Rust panics in userdata finalizers on drop. It also has positive performance impact.
+- Added `Debug::event()` to the hook's Debug structure
+- Simplified interface of `hook::HookTriggers`
+- Added finalizer to `ExtraData` in module mode. This helps avoiding memory leak on closing state when Lua unloads modules and frees memory.
+- Added `DeserializeOptions` struct to control deserializer behavior (`from_value_with` function).
+
+## v0.6.2
+
+- New functionality: `Lua::load_from_function()` and `Lua::create_c_function()`
+- Many optimizations in callbacks/userdata creation and methods execution
+
+## v0.6.1
+
+- Update `chunk!` documentation (stable Rust limitations)
+- Fixed Lua sequence table conversion to HashSet/BTreeSet
+- `once_cell` dependency lowered to 1.0
+
+## v0.6.0
+Changes since 0.5.4
+- New `UserDataFields` API
+- Full access to `UserData` metatables with support of setting arbitrary fields.
+- Implement `UserData` for `Rc<RefCell<T>>`/`Arc<Mutex<T>>`/`Arc<RwLock<T>>` where `T: UserData`.
+- Added `SerializeOptions` to to change default Lua serializer behaviour (eg. `nil/null/array` serialization)
+- Added `LuaOptions` to customize Lua/Rust behaviour (currently panic handling)
+- Added `ToLua`/`FromLua` implementation for `Box<str>` and `Box<[T]>`.
+- Added `Thread::reset()` for luajit/lua54 to recycle threads (coroutines) with attaching a new function.
+- Added `chunk!` macro support to load chunks of Lua code using the Rust tokenizer and optionally capturing Rust variables.
+- Improved errors reporting (`Error`'s `__tostring` method formats full stacktraces). This is useful in a module mode.
+- Added `String::to_string_lossy`
+- Various bugfixes and improvements
+
+Breaking changes:
+- Errors are always `Send + Sync` to be compatible with the anyhow crate.
+- Removed `Result` from `LuaSerdeExt::null()` and `LuaSerdeExt::array_metatable()` (never fails)
+- Removed `Result` from `Function::dump()` (never fails)
+- Removed `AnyUserData::has_metamethod()` (in favour of full access to metatables)
+
+## v0.6.0-beta.3
+
+- Errors are always `Send + Sync` to be compatible with anyhow crate
+- Implement `UserData` for `Rc<RefCell>`/`Arc<Mutex>`/`Arc<RwLock>`
+- Added `__ipairs` metamethod for Lua 5.2
+- Added `String::to_string_lossy`
+- Various bugfixes and improvements
+
+## v0.6.0-beta.2
+
+- [**Breaking**] Removed `AnyUserData::has_metamethod()`
+- Added `Thread::reset()` for luajit/lua54 to recycle threads.
+  It's possible to attach a new function to a thread (coroutine).
+- Added `chunk!` macro support to load chunks of Lua code using the Rust tokenizer and optionally capturing Rust variables.
+- Improved error reporting (`Error`'s `__tostring` method formats full stacktraces). This is useful in the module mode.
+
+## v0.6.0-beta.1
+
+- New `UserDataFields` API
+- Allow to define arbitrary MetaMethods
+- `MetaMethods::name()` is public
+- Do not trigger longjmp in Rust to prevent unwinding across FFI boundaries. See https://github.com/rust-lang/rust/issues/83541
+- Added `SerializeOptions` to to change default Lua serializer behaviour (eg. nil/null/array serialization)
+- [**Breaking**] Removed `Result` from `LuaSerdeExt::null()` and `LuaSerdeExt::array_metatable()` (never fails)
+- [**Breaking**] Removed `Result` from `Function::dump()` (never fails)
+- `ToLua`/`FromLua` implementation for `Box<str>` and `Box<[T]>`
+- [**Breaking**] Added `LuaOptions` to customize Lua/Rust behaviour (currently panic handling)
+- Various bugfixes and performance improvements
+
+## v0.5.4
+
+- Build script improvements
+- Improvements in panic handling (resume panic on value popping)
+- Fixed bug serializing 3rd party userdata (causes segfault)
+- Make error::Error non exhaustive
+
+## v0.5.3
+
+- Fixed bug when returning nil-prefixed multi values from async function (+ test)
+- Performance optimisation for async callbacks (polling)
+
+## v0.5.2
+
+- Some performance optimisations (callbacks)
+- `ToLua` implementation for `Cow<str>` and `Cow<CStr>`
+- Fixed bug with `Scope` destruction of partially polled futures
+
+## v0.5.1
+
+- Support cross compilation that should work well for vendored builds (including LuaJIT with some restrictions)
+- Fix numeric types conversion for 32bit Lua
+- Update tokio to 1.0 for async examples
+
+## v0.5.0
+
+- Serde support under `serialize` feature flag.
+- Re-export `mlua_derive`.
+- impl `ToLua` and `FromLua` for `HashSet` and `BTreeSet`
+
+## v0.4.2
+
+- Added `Function::dump()` to dump lua function to a binary chunk
+- Added `ChunkMode` enum to mark chunks as text or binary
+- Updated `set_memory_limit` doc
+
+## v0.4.0
+
+- Lua 5.4 support with `MetaMethod::Close`.
+- `lua53` feature is disabled by default. Now preferred Lua version have to be chosen explicitly.
+- Provide safety guarantees for Lua state, which means that potentially unsafe operations, like loading C modules (using `require` or `package.loadlib`) are disabled. Equivalent to the previous `Lua::new()` function is `Lua::unsafe_new()`.
+- New `send` feature to require `Send`.
+- New `module` feature, that disables linking to Lua Core Libraries. Required for modules.
+- Don't allow `'callback` outlive `'lua` in `Lua::create_function()` to fix [the unsoundness](tests/compile/static_callback_args.rs).
+- Added `Lua::into_static()` to make `'static` Lua state. This is useful to spawn async Lua threads that requires `'static`.
+- New function `Lua::set_memory_limit()` (similar to `rlua`) to enable memory restrictions in Lua VM (requires Lua >= 5.2).
+- `Scope`, temporary removed in v0.3, is back with async support.
+- Removed deprecated `Table::call()` function.
+- Added hooks support (backported from rlua 0.17).
+- New `AnyUserData::has_metamethod()` function.
+- LuaJIT 2.0.5 (the latest stable) support.
+- Various bug fixes and improvements.

Cargo.toml

@@ -1,52 +1,124 @@
 [package]
 name = "mlua"
-version = "0.2.2"
-authors = ["Aleksandr Orlenko <zxteam@pm.me>", "kyren <catherine@chucklefish.org>"]
-edition = "2018"
-repository = "https://github.com/khvzak/mlua"
+version = "0.11.3" # remember to update mlua_derive
+authors = ["Aleksandr Orlenko <zxteam@pm.me>", "kyren <catherine@kyju.org>"]
+rust-version = "1.79.0"
+edition = "2021"
+repository = "https://github.com/mlua-rs/mlua"
 documentation = "https://docs.rs/mlua"
 readme = "README.md"
-keywords = ["lua", "luajit"]
-categories = ["api-bindings"]
+keywords = ["lua", "luajit", "luau", "async", "scripting"]
+categories = ["api-bindings", "asynchronous"]
 license = "MIT"
-links = "lua"
-build = "build/main.rs"
 description = """
-High level bindings to Lua 5.1/5.2/5.3 (including LuaJIT)
-with support of writing native lua modules in Rust.
+High level bindings to Lua 5.4/5.3/5.2/5.1 (including LuaJIT) and Luau
+with async/await features and support of writing native Lua modules in Rust.
 """
 
-[badges]
-# github-actions = { repository = "khvzak/mlua", workflow = "CI" }
+[package.metadata.docs.rs]
+features = ["lua54", "vendored", "async", "send", "serde", "macros"]
+rustdoc-args = ["--cfg", "docsrs"]
 
 [workspace]
 members = [
     "mlua_derive",
+    "mlua-sys",
 ]
 
 [features]
-default = ["lua53"]
-lua53 = []
-lua52 = []
-lua51 = []
-luajit = []
-vendored = ["lua-src", "luajit-src"]
+lua54 = ["ffi/lua54"]
+lua53 = ["ffi/lua53"]
+lua52 = ["ffi/lua52"]
+lua51 = ["ffi/lua51"]
+luajit = ["ffi/luajit"]
+luajit52 = ["luajit", "ffi/luajit52"]
+luau = ["ffi/luau"]
+luau-jit = ["luau", "ffi/luau-codegen"]
+luau-vector4 = ["luau", "ffi/luau-vector4"]
+vendored = ["ffi/vendored"]
+module = ["mlua_derive", "ffi/module"]
+async = ["dep:futures-util"]
+send = ["error-send"]
+error-send = []
+serde = ["dep:serde", "dep:erased-serde", "dep:serde-value", "bstr/serde"]
+macros = ["mlua_derive/macros"]
+anyhow = ["dep:anyhow", "error-send"]
+userdata-wrappers = ["parking_lot/send_guard"]
+
+# deprecated features
+serialize = ["serde"]
 
 [dependencies]
-num-traits = { version = "0.2.6" }
-bstr = { version = "0.2", features = ["std"], default_features = false }
+mlua_derive = { version = "=0.11.0", optional = true, path = "mlua_derive" }
+bstr = { version = "1.0", features = ["std"], default-features = false }
+either = "1.0"
+num-traits = { version = "0.2.14" }
+rustc-hash = "2.0"
+futures-util = { version = "0.3", optional = true, default-features = false, features = ["std"] }
+serde = { version = "1.0", optional = true }
+erased-serde = { version = "0.4", optional = true }
+serde-value = { version = "0.7", optional = true }
+parking_lot = { version = "0.12", features = ["arc_lock"] }
+anyhow = { version = "1.0", optional = true }
+rustversion = "1.0"
 
-[build-dependencies]
-cc = { version = "1.0" }
-pkg-config = { version = "0.3.11" }
-lua-src = { version = "535.0.1", optional = true }
-luajit-src = { version = "210.0.0", optional = true }
+ffi = { package = "mlua-sys", version = "0.8.3", path = "mlua-sys" }
 
 [dev-dependencies]
-rustyline = "5.0"
-criterion = "0.2.0"
 trybuild = "1.0"
+hyper = { version = "1.2", features = ["full"] }
+hyper-util = { version = "0.1.3", features = ["full"] }
+http-body-util = "0.1.1"
+reqwest = { version = "0.12", features = ["json"] }
+tokio = { version = "1.0", features = ["macros", "rt", "time"] }
+serde = { version = "1.0", features = ["derive"] }
+serde_json = { version = "1.0", features = ["arbitrary_precision"] }
+maplit = "1.0"
+tempfile = "3"
+static_assertions = "1.0"
+
+[target.'cfg(not(target_arch = "wasm32"))'.dev-dependencies]
+criterion = { version = "0.7", features = ["async_tokio"] }
+rustyline = "17.0"
+tokio = { version = "1.0", features = ["full"] }
+
+[lints.rust]
+unexpected_cfgs = { level = "allow", check-cfg = ['cfg(tarpaulin_include)'] }
 
 [[bench]]
 name = "benchmark"
 harness = false
+required-features = ["async"]
+
+[[bench]]
+name = "serde"
+harness = false
+required-features = ["serde"]
+
+[[example]]
+name = "async_http_client"
+required-features = ["async", "macros"]
+
+[[example]]
+name = "async_http_reqwest"
+required-features = ["async", "serde", "macros"]
+
+[[example]]
+name = "async_http_server"
+required-features = ["async", "macros", "send"]
+
+[[example]]
+name = "async_tcp_server"
+required-features = ["async", "macros", "send"]
+
+[[example]]
+name = "guided_tour"
+required-features = ["macros"]
+
+[[example]]
+name = "serde"
+required-features = ["serde"]
+
+[[example]]
+name = "userdata"
+required-features = ["macros"]

FAQ.md

@@ -0,0 +1,21 @@
+# mlua FAQ
+
+This file is for general questions that don't fit into the README or crate docs.
+
+## Loading a C module fails with error `undefined symbol: lua_xxx`. How to fix?
+
+Add the following rustflags to your [.cargo/config](http://doc.crates.io/config.html) in order to properly export Lua symbols:
+
+```toml
+[target.x86_64-unknown-linux-gnu]
+rustflags = ["-C", "link-args=-rdynamic"]
+
+[target.x86_64-apple-darwin]
+rustflags = ["-C", "link-args=-rdynamic"]
+```
+
+## I want to add support for a Lua VM fork to mlua. Do you accept pull requests?
+
+Adding new feature flag to support a Lua VM fork is a major step that requires huge effort to maintain it.
+Regular updates, testing, checking compatibility, etc.
+That's why I don't plan to support new Lua VM forks or other languages in mlua.

LICENSE

@@ -3,7 +3,7 @@ below:
 
 MIT License
 
-Copyright (c) 2019 A. Orlenko
+Copyright (c) 2019-2021 A. Orlenko
 Copyright (c) 2017 rlua
 
 Permission is hereby granted, free of charge, to any person obtaining a copy

README.md

@@ -1,47 +1,135 @@
 # mlua
-[![Build Status]][github-actions] [![Latest Version]][crates.io] [![API Documentation]][docs.rs]
+[![Build Status]][github-actions] [![Latest Version]][crates.io] [![API Documentation]][docs.rs] [![Coverage Status]][codecov.io] ![MSRV]
 
-[Build Status]: https://github.com/khvzak/mlua/workflows/CI/badge.svg
-[github-actions]: https://github.com/khvzak/mlua/actions
+[Build Status]: https://github.com/mlua-rs/mlua/workflows/CI/badge.svg
+[github-actions]: https://github.com/mlua-rs/mlua/actions
 [Latest Version]: https://img.shields.io/crates/v/mlua.svg
 [crates.io]: https://crates.io/crates/mlua
 [API Documentation]: https://docs.rs/mlua/badge.svg
 [docs.rs]: https://docs.rs/mlua
+[Coverage Status]: https://codecov.io/gh/mlua-rs/mlua/branch/main/graph/badge.svg?token=99339FS1CG
+[codecov.io]: https://codecov.io/gh/mlua-rs/mlua
+[MSRV]: https://img.shields.io/badge/rust-1.79+-brightgreen.svg?&logo=rust
 
-[Guided Tour](examples/guided_tour.rs)
+[Guided Tour] | [Benchmarks] | [FAQ]
 
-A fork of [rlua 0.15](https://github.com/kyren/rlua/tree/0.15.3) which provides a high level
-interface between Rust and Lua. Unlike `rlua` , `mlua` supports Lua 5.1 (including LuaJIT), 5.2 and 5.3.
-The `mlua` goal is to be an easy to use, practical and flexible API between Rust and Lua but
-*__not__* always 100% safe due to the Lua VM nature. Also, `mlua` provides a way to write native lua
-modules in Rust.
+[Guided Tour]: examples/guided_tour.rs
+[Benchmarks]: https://github.com/khvzak/script-bench-rs
+[FAQ]: FAQ.md
+
+`mlua` is a set of bindings to the [Lua](https://www.lua.org) programming language for Rust with a goal to provide a
+_safe_ (as much as possible), high level, easy to use, practical and flexible API.
+
+Started as an `rlua` fork, `mlua` supports Lua 5.4, 5.3, 5.2, 5.1 (including LuaJIT) and [Luau] and allows writing native Lua modules in Rust as well as using Lua in a standalone mode.
+
+`mlua` is tested on Windows/macOS/Linux including module mode in [GitHub Actions] on `x86_64` platforms and cross-compilation to `aarch64` (other targets are also supported).
+
+WebAssembly (WASM) is supported through `wasm32-unknown-emscripten` target for all Lua/Luau versions excluding JIT.
+
+[GitHub Actions]: https://github.com/mlua-rs/mlua/actions
+[Luau]: https://luau.org
 
 ## Usage
 
-### Choosing Lua version
+### Feature flags
 
-The following features could be used to choose Lua version: `lua53` (default), `lua52`, `lua51` and `luajit`.
+`mlua` uses feature flags to reduce the amount of dependencies and compiled code, and allow to choose only required set of features.
+Below is a list of the available feature flags. By default `mlua` does not enable any features.
 
-By default mlua uses `pkg-config` tool to find lua includes and lib.
-In most cases it works as desired, although sometimes could be more preferable to use a custom lua library.
-To achieve this, mlua supports `LUA_INC`, `LUA_LIB`, `LUA_LIB_NAME` and `LUA_LINK` environment variables.
-`LUA_LINK` is optional and may be `dylib` (a dynamic library) or `static` (a static library, `.a` archive).
+* `lua54`: enable Lua [5.4] support
+* `lua53`: enable Lua [5.3] support
+* `lua52`: enable Lua [5.2] support
+* `lua51`: enable Lua [5.1] support
+* `luajit`: enable [LuaJIT] support
+* `luajit52`: enable [LuaJIT] support with partial compatibility with Lua 5.2
+* `luau`: enable [Luau] support (auto vendored mode)
+* `luau-jit`: enable [Luau] support with JIT backend.
+* `luau-vector4`: enable [Luau] support with 4-dimensional vector.
+* `vendored`: build static Lua(JIT) libraries from sources during `mlua` compilation using [lua-src] or [luajit-src]
+* `module`: enable module mode (building loadable `cdylib` library for Lua)
+* `async`: enable async/await support (any executor can be used, eg. [tokio] or [async-std])
+* `send`: make `mlua::Lua: Send + Sync` (adds [`Send`] requirement to `mlua::Function` and `mlua::UserData`)
+* `error-send`: make `mlua:Error: Send + Sync`
+* `serde`: add serialization and deserialization support to `mlua` types using [serde]
+* `macros`: enable procedural macros (such as `chunk!`)
+* `anyhow`: enable `anyhow::Error` conversion into Lua
+* `userdata-wrappers`: opt into `impl UserData` for `Rc<T>`/`Arc<T>`/`Rc<RefCell<T>>`/`Arc<Mutex<T>>` where `T: UserData`
 
-An example how to use them:
-``` sh
-my_project $ LUA_INC=$HOME/tmp/lua-5.2.4/src LUA_LIB=$HOME/tmp/lua-5.2.4/src LUA_LIB_NAME=lua LUA_LINK=static cargo build
+[5.4]: https://www.lua.org/manual/5.4/manual.html
+[5.3]: https://www.lua.org/manual/5.3/manual.html
+[5.2]: https://www.lua.org/manual/5.2/manual.html
+[5.1]: https://www.lua.org/manual/5.1/manual.html
+[LuaJIT]: https://luajit.org/
+[Luau]: https://github.com/luau-lang/luau
+[lua-src]: https://github.com/mlua-rs/lua-src-rs
+[luajit-src]: https://github.com/mlua-rs/luajit-src-rs
+[tokio]: https://github.com/tokio-rs/tokio
+[async-std]: https://github.com/async-rs/async-std
+[`Send`]: https://doc.rust-lang.org/std/marker/trait.Send.html
+[serde]: https://github.com/serde-rs/serde
+
+### Async/await support
+
+`mlua` supports async/await for all Lua versions including Luau.
+
+This works using Lua [coroutines](https://www.lua.org/manual/5.3/manual.html#2.6) and requires running [Thread](https://docs.rs/mlua/latest/mlua/struct.Thread.html) along with enabling `feature = "async"` in `Cargo.toml`.
+
+**Examples**:
+- [HTTP Client](examples/async_http_client.rs)
+- [HTTP Client (json)](examples/async_http_reqwest.rs)
+- [HTTP Server](examples/async_http_server.rs)
+- [TCP Server](examples/async_tcp_server.rs)
+
+
+**shell command examples**:
+```shell
+# async http client (hyper)
+cargo run --example async_http_client --features=lua54,async,macros
+
+# async http client (reqwest)
+cargo run --example async_http_reqwest --features=lua54,async,macros,serde
+
+# async http server
+cargo run --example async_http_server --features=lua54,async,macros,send
+curl -v http://localhost:3000
 ```
 
-`mlua` also supports vendored lua/luajit using the auxilary crates [lua-src](https://crates.io/crates/lua-src) and
+### Serde support
+
+With the `serde` feature flag enabled, `mlua` allows you to serialize/deserialize any type that implements [`serde::Serialize`] and [`serde::Deserialize`] into/from [`mlua::Value`]. In addition, `mlua` provides the [`serde::Serialize`] trait implementation for `mlua::Value` (including `UserData` support).
+
+[Example](examples/serde.rs)
+
+[`serde::Serialize`]: https://docs.serde.rs/serde/ser/trait.Serialize.html
+[`serde::Deserialize`]: https://docs.serde.rs/serde/de/trait.Deserialize.html
+[`mlua::Value`]: https://docs.rs/mlua/latest/mlua/enum.Value.html
+
+### Compiling
+
+You have to enable one of the features: `lua54`, `lua53`, `lua52`, `lua51`, `luajit(52)` or `luau`, according to the chosen Lua version.
+
+By default `mlua` uses `pkg-config` to find Lua includes and libraries for the chosen Lua version.
+In most cases it works as desired, although sometimes it may be preferable to use a custom Lua library.
+To achieve this, mlua supports the `LUA_LIB`, `LUA_LIB_NAME` and `LUA_LINK` environment variables.
+`LUA_LINK` is optional and may be `dylib` (a dynamic library) or `static` (a static library, `.a` archive).
+
+An example of how to use them:
+``` sh
+my_project $ LUA_LIB=$HOME/tmp/lua-5.2.4/src LUA_LIB_NAME=lua LUA_LINK=static cargo build
+```
+
+`mlua` also supports vendored Lua/LuaJIT using the auxiliary crates [lua-src](https://crates.io/crates/lua-src) and
 [luajit-src](https://crates.io/crates/luajit-src).
-Just enable the `vendored` feature and cargo will automatically build and link specified lua/luajit version. This is the easiest way to get started with mlua.
+Just enable the `vendored` feature and cargo will automatically build and link the specified Lua/LuaJIT version. This is the easiest way to get started with `mlua`.
 
 ### Standalone mode
-Add to `Cargo.toml` :
+In standalone mode, `mlua` allows adding scripting support to your application with a gently configured Lua runtime to ensure safety and soundness.
+
+Add to `Cargo.toml`:
 
 ``` toml
 [dependencies]
-mlua = "0.2"
+mlua = { version = "0.11", features = ["lua54", "vendored"] }
 ```
 
 `main.rs`
@@ -65,23 +153,23 @@ fn main() -> LuaResult<()> {
 ```
 
 ### Module mode
+In module mode, `mlua` allows creating a compiled Lua module that can be loaded from Lua code using [`require`](https://www.lua.org/manual/5.4/manual.html#pdf-require). In this case `mlua` uses an external Lua runtime which could lead to potential unsafety due to the unpredictability of the Lua environment and usage of libraries such as [`debug`](https://www.lua.org/manual/5.4/manual.html#6.10).
 
-Add to `Cargo.toml` :
+[Example](examples/module)
+
+Add to `Cargo.toml`:
 
 ``` toml
 [lib]
 crate-type = ["cdylib"]
 
 [dependencies]
-mlua = "0.2"
-mlua_derive = "0.2"
+mlua = { version = "0.11", features = ["lua54", "module"] }
 ```
 
-`lib.rs` :
+`lib.rs`:
 
 ``` rust
-#[macro_use]
-extern crate mlua_derive;
 use mlua::prelude::*;
 
 fn hello(_: &Lua, name: String) -> LuaResult<()> {
@@ -89,7 +177,7 @@ fn hello(_: &Lua, name: String) -> LuaResult<()> {
     Ok(())
 }
 
-#[lua_module]
+#[mlua::lua_module]
 fn my_module(lua: &Lua) -> LuaResult<LuaTable> {
     let exports = lua.create_table()?;
     exports.set("hello", lua.create_function(hello)?)?;
@@ -97,32 +185,64 @@ fn my_module(lua: &Lua) -> LuaResult<LuaTable> {
 }
 ```
 
-And then (macos example):
+And then (**macOS** example):
 
 ``` sh
-$ cargo build
+$ cargo rustc -- -C link-arg=-undefined -C link-arg=dynamic_lookup
 $ ln -s ./target/debug/libmy_module.dylib ./my_module.so
-$ lua5.3 -e 'require("my_module").hello("world")'
+$ lua5.4 -e 'require("my_module").hello("world")'
 hello, world!
 ```
 
+On macOS, you need to set additional linker arguments. One option is to compile with `cargo rustc --release -- -C link-arg=-undefined -C link-arg=dynamic_lookup`, the other is to create a `.cargo/config.toml` with the following content:
+``` toml
+[target.x86_64-apple-darwin]
+rustflags = [
+  "-C", "link-arg=-undefined",
+  "-C", "link-arg=dynamic_lookup",
+]
+
+[target.aarch64-apple-darwin]
+rustflags = [
+  "-C", "link-arg=-undefined",
+  "-C", "link-arg=dynamic_lookup",
+]
+```
+On Linux you can build modules normally with `cargo build --release`.
+
+On Windows the target module will be linked with the `lua5x.dll` library (depending on your feature flags).
+Your main application should provide this library.
+
+Module builds don't require Lua binaries or headers to be installed on the system.
+
+### Publishing to luarocks.org
+
+There is a LuaRocks build backend for mlua modules: [`luarocks-build-rust-mlua`].
+
+Modules written in Rust and published to luarocks:
+- [`decasify`](https://github.com/alerque/decasify)
+- [`lua-ryaml`](https://github.com/khvzak/lua-ryaml)
+- [`tiktoken_core`](https://github.com/gptlang/lua-tiktoken)
+- [`toml-edit`](https://github.com/vhyrro/toml-edit.lua)
+- [`typst-lua`](https://github.com/rousbound/typst-lua)
+
+[`luarocks-build-rust-mlua`]: https://luarocks.org/modules/khvzak/luarocks-build-rust-mlua
+
 ## Safety
 
-One of the `mlua` goals is to provide *safe* API between Rust and Lua.
-Every place where the Lua C API may trigger an error longjmp
-in any way is protected by `lua_pcall` , and the user of the library is protected
-from directly interacting with unsafe things like the Lua stack, and there is
-overhead associated with this safety.
+One of `mlua`'s goals is to provide a *safe* API between Rust and Lua.
+Every place where the Lua C API may trigger an error longjmp is protected by `lua_pcall`,
+and the user of the library is protected from directly interacting with unsafe things like the Lua stack.
+There is overhead associated with this safety.
 
 Unfortunately, `mlua` does not provide absolute safety even without using `unsafe` .
-This library contains a huge amount of unsafe code. There are almost
-certainly bugs still lurking in this library!  It is surprisingly, fiendishly
-difficult to use the Lua C API without the potential for unsafety.
+This library contains a huge amount of unsafe code. There are almost certainly bugs still lurking in this library!
+It is surprisingly, fiendishly difficult to use the Lua C API without the potential for unsafety.
 
 ## Panic handling
 
-`mlua` wraps panics that are generated inside Rust callbacks in a regular Lua error. Panics could be
-resumed then by propagating the Lua error to Rust code.
+`mlua` wraps panics that are generated inside Rust callbacks in a regular Lua error. Panics can then be
+resumed by returning or propagating the Lua error to Rust code.
 
 For example:
 ``` rust
@@ -141,24 +261,34 @@ let _ = lua.load(r#"
 unreachable!()
 ```
 
-`mlua` should also be panic safe in another way as well, which is that any `Lua`
-instances or handles remains usable after a user generated panic, and such
-panics should not break internal invariants or leak Lua stack space. This is
-mostly important to safely use `mlua` types in Drop impls, as you should not be
+Optionally, `mlua` can disable Rust panic catching in Lua via `pcall`/`xpcall` and automatically resume
+them across the Lua API boundary. This is controlled via `LuaOptions` and done by wrapping the Lua `pcall`/`xpcall`
+functions to prevent catching errors that are wrapped Rust panics.
+
+`mlua` should also be panic safe in another way as well, which is that any `Lua` instances or handles
+remain usable after a user generated panic, and such panics should not break internal invariants or
+leak Lua stack space. This is mostly important to safely use `mlua` types in Drop impls, as you should not be
 using panics for general error handling.
 
 Below is a list of `mlua` behaviors that should be considered a bug.
 If you encounter them, a bug report would be very welcome:
 
-  + If your program panics with a message that contains the string "mlua internal error", this is a  bug.
+  + If you can cause UB with `mlua` without typing the word "unsafe", this is a bug.
 
-  + The above is true even for the internal panic about running out of stack space!  There are a few ways to generate normal script errors by running out of stack, but if you encounter a *panic* based on running out of stack, this is a bug.
+  + If your program panics with a message that contains the string "mlua internal error", this is a bug.
 
-  + Lua C API errors are handled by lonjmp. All instances where the Lua C API would otherwise longjmp over calling stack frames should be guarded against, except in internal callbacks where this is intentional. If you detect that `mlua` is triggering a longjmp over your Rust stack frames, this is a bug!
+  + Lua C API errors are handled by longjmp. All instances where the Lua C API would otherwise longjmp over calling stack frames should be guarded against, except in internal callbacks where this is intentional. If you detect that `mlua` is triggering a longjmp over your Rust stack frames, this is a bug!
 
   + If you detect that, after catching a panic or during a Drop triggered from a panic, a `Lua` or handle method is triggering other bugs or there is a Lua stack space leak, this is a bug. `mlua` instances are supposed to remain fully usable in the face of user generated panics. This guarantee does not extend to panics marked with "mlua internal error" simply because that is already indicative of a separate bug.
 
+## Sandboxing
+
+Please check the [Luau Sandboxing] page if you are interested in running untrusted Lua scripts in a controlled environment.
+
+`mlua` provides the `Lua::sandbox` method for enabling sandbox mode (Luau only).
+
+[Luau Sandboxing]: https://luau.org/sandbox
+
 ## License
 
-This project is licensed under the [MIT license](LICENSE)
-
+This project is licensed under the [MIT license](LICENSE).

benches/benchmark.rs

@@ -1,22 +1,24 @@
-#![cfg_attr(
-    all(feature = "luajit", target_os = "macos", target_arch = "x86_64"),
-    feature(link_args)
-)]
-
-#[cfg_attr(
-    all(feature = "luajit", target_os = "macos", target_arch = "x86_64"),
-    link_args = "-pagezero_size 10000 -image_base 100000000"
-)]
-extern "system" {}
+use std::sync::atomic::{AtomicUsize, Ordering};
+use std::time::Duration;
 
 use criterion::{criterion_group, criterion_main, BatchSize, Criterion};
+use tokio::runtime::Runtime;
+use tokio::task;
+
 use mlua::prelude::*;
 
-fn create_table(c: &mut Criterion) {
-    c.bench_function("create table", |b| {
-        b.iter_batched_ref(
-            || Lua::new(),
-            |lua| {
+fn collect_gc_twice(lua: &Lua) {
+    lua.gc_collect().unwrap();
+    lua.gc_collect().unwrap();
+}
+
+fn table_create_empty(c: &mut Criterion) {
+    let lua = Lua::new();
+
+    c.bench_function("table [create empty]", |b| {
+        b.iter_batched(
+            || collect_gc_twice(&lua),
+            |_| {
                 lua.create_table().unwrap();
             },
             BatchSize::SmallInput,
@@ -24,61 +26,55 @@ fn create_table(c: &mut Criterion) {
     });
 }
 
-fn create_array(c: &mut Criterion) {
-    c.bench_function("create array 10", |b| {
-        b.iter_batched_ref(
-            || Lua::new(),
-            |lua| {
-                let table = lua.create_table().unwrap();
-                for i in 1..11 {
-                    table.set(i, i).unwrap();
-                }
+fn table_create_array(c: &mut Criterion) {
+    let lua = Lua::new();
+
+    c.bench_function("table [create array]", |b| {
+        b.iter_batched(
+            || collect_gc_twice(&lua),
+            |_| {
+                lua.create_sequence_from(1..=10).unwrap();
             },
             BatchSize::SmallInput,
         );
     });
 }
 
-fn create_string_table(c: &mut Criterion) {
-    c.bench_function("create string table 10", |b| {
-        b.iter_batched_ref(
-            || Lua::new(),
-            |lua| {
-                let table = lua.create_table().unwrap();
-                for &s in &["1", "2", "3", "4", "5", "6", "7", "8", "9", "10"] {
-                    let s = lua.create_string(s).unwrap();
-                    table.set(s.clone(), s).unwrap();
-                }
+fn table_create_hash(c: &mut Criterion) {
+    let lua = Lua::new();
+
+    c.bench_function("table [create hash]", |b| {
+        b.iter_batched(
+            || collect_gc_twice(&lua),
+            |_| {
+                lua.create_table_from(
+                    ["1", "2", "3", "4", "5", "6", "7", "8", "9", "10"]
+                        .into_iter()
+                        .map(|s| (s, s)),
+                )
+                .unwrap();
             },
             BatchSize::SmallInput,
         );
     });
 }
 
-fn call_add_function(c: &mut Criterion) {
-    c.bench_function("call add function 3 10", |b| {
-        b.iter_batched_ref(
+fn table_get_set(c: &mut Criterion) {
+    let lua = Lua::new();
+
+    c.bench_function("table [get and set]", |b| {
+        b.iter_batched(
             || {
-                let lua = Lua::new();
-                let f = {
-                    let f: LuaFunction = lua
-                        .load(
-                            r#"
-                                function(a, b, c)
-                                    return a + b + c
-                                end
-                            "#,
-                        )
-                        .eval()
-                        .unwrap();
-                    lua.create_registry_value(f).unwrap()
-                };
-                (lua, f)
+                collect_gc_twice(&lua);
+                lua.create_table().unwrap()
             },
-            |(lua, f)| {
-                let add_function: LuaFunction = lua.registry_value(f).unwrap();
-                for i in 0..10 {
-                    let _result: i64 = add_function.call((i, i + 1, i + 2)).unwrap();
+            |table| {
+                for (i, s) in ["a", "b", "c", "d", "e", "f", "g", "h", "i", "j"]
+                    .into_iter()
+                    .enumerate()
+                {
+                    table.raw_set(s, i).unwrap();
+                    assert_eq!(table.raw_get::<usize>(s).unwrap(), i);
                 }
             },
             BatchSize::SmallInput,
@@ -86,105 +82,352 @@ fn call_add_function(c: &mut Criterion) {
     });
 }
 
-fn call_add_callback(c: &mut Criterion) {
-    c.bench_function("call callback add 2 10", |b| {
-        b.iter_batched_ref(
-            || {
-                let lua = Lua::new();
-                let f = {
-                    let c: LuaFunction = lua
-                        .create_function(|_, (a, b, c): (i64, i64, i64)| Ok(a + b + c))
-                        .unwrap();
-                    lua.globals().set("callback", c).unwrap();
-                    let f: LuaFunction = lua
-                        .load(
-                            r#"
-                            function()
-                                for i = 1,10 do
-                                    callback(i, i, i)
-                                end
-                            end
-                        "#,
-                        )
-                        .eval()
-                        .unwrap();
-                    lua.create_registry_value(f).unwrap()
-                };
-                (lua, f)
-            },
-            |(lua, f)| {
-                let entry_function: LuaFunction = lua.registry_value(f).unwrap();
-                entry_function.call::<_, ()>(()).unwrap();
-            },
-            BatchSize::SmallInput,
-        );
-    });
-}
+fn table_traversal_pairs(c: &mut Criterion) {
+    let lua = Lua::new();
 
-fn call_append_callback(c: &mut Criterion) {
-    c.bench_function("call callback append 10", |b| {
-        b.iter_batched_ref(
-            || {
-                let lua = Lua::new();
-                let f = {
-                    let c: LuaFunction = lua
-                        .create_function(|_, (a, b): (LuaString, LuaString)| {
-                            Ok(format!("{}{}", a.to_str()?, b.to_str()?))
-                        })
-                        .unwrap();
-                    lua.globals().set("callback", c).unwrap();
-                    let f: LuaFunction = lua
-                        .load(
-                            r#"
-                            function()
-                                for _ = 1,10 do
-                                    callback("a", "b")
-                                end
-                            end
-                        "#,
-                        )
-                        .eval()
-                        .unwrap();
-                    lua.create_registry_value(f).unwrap()
-                };
-                (lua, f)
-            },
-            |(lua, f)| {
-                let entry_function: LuaFunction = lua.registry_value(f).unwrap();
-                entry_function.call::<_, ()>(()).unwrap();
-            },
-            BatchSize::SmallInput,
-        );
-    });
-}
-
-fn create_registry_values(c: &mut Criterion) {
-    c.bench_function("create registry 10", |b| {
-        b.iter_batched_ref(
-            || Lua::new(),
-            |lua| {
-                for _ in 0..10 {
-                    lua.create_registry_value(lua.pack(true).unwrap()).unwrap();
+    c.bench_function("table [traversal pairs]", |b| {
+        b.iter_batched(
+            || lua.globals(),
+            |globals| {
+                for kv in globals.pairs::<String, LuaValue>() {
+                    let (_k, _v) = kv.unwrap();
                 }
-                lua.expire_registry_values();
             },
             BatchSize::SmallInput,
         );
     });
 }
 
-fn create_userdata(c: &mut Criterion) {
-    struct UserData(i64);
+fn table_traversal_for_each(c: &mut Criterion) {
+    let lua = Lua::new();
+
+    c.bench_function("table [traversal for_each]", |b| {
+        b.iter_batched(
+            || lua.globals(),
+            |globals| globals.for_each::<String, LuaValue>(|_k, _v| Ok(())),
+            BatchSize::SmallInput,
+        );
+    });
+}
+
+fn table_traversal_sequence(c: &mut Criterion) {
+    let lua = Lua::new();
+
+    let table = lua.create_sequence_from(1..1000).unwrap();
+
+    c.bench_function("table [traversal sequence]", |b| {
+        b.iter_batched(
+            || table.clone(),
+            |table| {
+                for v in table.sequence_values::<i32>() {
+                    let _i = v.unwrap();
+                }
+            },
+            BatchSize::SmallInput,
+        );
+    });
+}
+
+fn table_ref_clone(c: &mut Criterion) {
+    let lua = Lua::new();
+
+    let t = lua.create_table().unwrap();
+
+    c.bench_function("table [ref clone]", |b| {
+        b.iter_batched(
+            || collect_gc_twice(&lua),
+            |_| {
+                let _t2 = t.clone();
+            },
+            BatchSize::SmallInput,
+        );
+    });
+}
+
+fn function_create(c: &mut Criterion) {
+    let lua = Lua::new();
+
+    c.bench_function("function [create Rust]", |b| {
+        b.iter_batched(
+            || collect_gc_twice(&lua),
+            |_| {
+                lua.create_function(|_, ()| Ok(123)).unwrap();
+            },
+            BatchSize::SmallInput,
+        );
+    });
+}
+
+fn function_call_sum(c: &mut Criterion) {
+    let lua = Lua::new();
+
+    let sum = lua
+        .create_function(|_, (a, b, c): (i64, i64, i64)| Ok(a + b - c))
+        .unwrap();
+
+    c.bench_function("function [call Rust sum]", |b| {
+        b.iter_batched(
+            || collect_gc_twice(&lua),
+            |_| {
+                assert_eq!(sum.call::<i64>((10, 20, 30)).unwrap(), 0);
+            },
+            BatchSize::SmallInput,
+        );
+    });
+}
+
+fn function_call_lua_sum(c: &mut Criterion) {
+    let lua = Lua::new();
+
+    let sum = lua
+        .load("function(a, b, c) return a + b - c end")
+        .eval::<LuaFunction>()
+        .unwrap();
+
+    c.bench_function("function [call Lua sum]", |b| {
+        b.iter_batched(
+            || collect_gc_twice(&lua),
+            |_| {
+                assert_eq!(sum.call::<i64>((10, 20, 30)).unwrap(), 0);
+            },
+            BatchSize::SmallInput,
+        );
+    });
+}
+
+fn function_call_concat(c: &mut Criterion) {
+    let lua = Lua::new();
+
+    let concat = lua
+        .create_function(|_, (a, b): (LuaString, LuaString)| Ok(format!("{}{}", a.to_str()?, b.to_str()?)))
+        .unwrap();
+    let i = AtomicUsize::new(0);
+
+    c.bench_function("function [call Rust concat string]", |b| {
+        b.iter_batched(
+            || {
+                collect_gc_twice(&lua);
+                i.fetch_add(1, Ordering::Relaxed)
+            },
+            |i| {
+                assert_eq!(concat.call::<LuaString>(("num:", i)).unwrap(), format!("num:{i}"));
+            },
+            BatchSize::SmallInput,
+        );
+    });
+}
+
+fn function_call_lua_concat(c: &mut Criterion) {
+    let lua = Lua::new();
+
+    let concat = lua
+        .load("function(a, b) return a..b end")
+        .eval::<LuaFunction>()
+        .unwrap();
+    let i = AtomicUsize::new(0);
+
+    c.bench_function("function [call Lua concat string]", |b| {
+        b.iter_batched(
+            || {
+                collect_gc_twice(&lua);
+                i.fetch_add(1, Ordering::Relaxed)
+            },
+            |i| {
+                assert_eq!(concat.call::<LuaString>(("num:", i)).unwrap(), format!("num:{i}"));
+            },
+            BatchSize::SmallInput,
+        );
+    });
+}
+
+fn function_async_call_sum(c: &mut Criterion) {
+    let options = LuaOptions::new().thread_pool_size(1024);
+    let lua = Lua::new_with(LuaStdLib::ALL_SAFE, options).unwrap();
+
+    let sum = lua
+        .create_async_function(|_, (a, b, c): (i64, i64, i64)| async move {
+            task::yield_now().await;
+            Ok(a + b - c)
+        })
+        .unwrap();
+
+    c.bench_function("function [async call Rust sum]", |b| {
+        let rt = Runtime::new().unwrap();
+        b.to_async(rt).iter_batched(
+            || collect_gc_twice(&lua),
+            |_| async {
+                assert_eq!(sum.call_async::<i64>((10, 20, 30)).await.unwrap(), 0);
+            },
+            BatchSize::SmallInput,
+        );
+    });
+}
+
+fn registry_value_create(c: &mut Criterion) {
+    let lua = Lua::new();
+    lua.gc_stop();
+
+    c.bench_function("registry value [create]", |b| {
+        b.iter_batched(
+            || collect_gc_twice(&lua),
+            |_| lua.create_registry_value("hello").unwrap(),
+            BatchSize::SmallInput,
+        );
+    });
+}
+
+fn registry_value_get(c: &mut Criterion) {
+    let lua = Lua::new();
+    lua.gc_stop();
+
+    let value = lua.create_registry_value("hello").unwrap();
+
+    c.bench_function("registry value [get]", |b| {
+        b.iter_batched(
+            || collect_gc_twice(&lua),
+            |_| {
+                assert_eq!(lua.registry_value::<LuaString>(&value).unwrap(), "hello");
+            },
+            BatchSize::SmallInput,
+        );
+    });
+}
+
+fn userdata_create(c: &mut Criterion) {
+    struct UserData(#[allow(unused)] i64);
     impl LuaUserData for UserData {}
 
-    c.bench_function("create userdata 10", |b| {
-        b.iter_batched_ref(
-            || Lua::new(),
-            |lua| {
-                let table: LuaTable = lua.create_table().unwrap();
-                for i in 1..11 {
-                    table.set(i, UserData(i)).unwrap();
-                }
+    let lua = Lua::new();
+
+    c.bench_function("userdata [create]", |b| {
+        b.iter_batched(
+            || collect_gc_twice(&lua),
+            |_| {
+                lua.create_userdata(UserData(123)).unwrap();
+            },
+            BatchSize::SmallInput,
+        );
+    });
+}
+
+fn userdata_call_index(c: &mut Criterion) {
+    struct UserData(#[allow(unused)] i64);
+    impl LuaUserData for UserData {
+        fn add_methods<M: LuaUserDataMethods<Self>>(methods: &mut M) {
+            methods.add_meta_method(LuaMetaMethod::Index, move |_, _, key: LuaString| Ok(key));
+        }
+    }
+
+    let lua = Lua::new();
+    let ud = lua.create_userdata(UserData(123)).unwrap();
+    let index = lua
+        .load("function(ud) return ud.test end")
+        .eval::<LuaFunction>()
+        .unwrap();
+
+    c.bench_function("userdata [call index]", |b| {
+        b.iter_batched(
+            || collect_gc_twice(&lua),
+            |_| {
+                assert_eq!(index.call::<LuaString>(&ud).unwrap(), "test");
+            },
+            BatchSize::SmallInput,
+        );
+    });
+}
+
+fn userdata_call_method(c: &mut Criterion) {
+    struct UserData(i64);
+    impl LuaUserData for UserData {
+        fn add_methods<M: LuaUserDataMethods<Self>>(methods: &mut M) {
+            methods.add_method("add", |_, this, i: i64| Ok(this.0 + i));
+        }
+    }
+
+    let lua = Lua::new();
+    let ud = lua.create_userdata(UserData(123)).unwrap();
+    let method = lua
+        .load("function(ud, i) return ud:add(i) end")
+        .eval::<LuaFunction>()
+        .unwrap();
+    let i = AtomicUsize::new(0);
+
+    c.bench_function("userdata [call method]", |b| {
+        b.iter_batched(
+            || {
+                collect_gc_twice(&lua);
+                i.fetch_add(1, Ordering::Relaxed)
+            },
+            |i| {
+                assert_eq!(method.call::<usize>((&ud, i)).unwrap(), 123 + i);
+            },
+            BatchSize::SmallInput,
+        );
+    });
+}
+
+// A userdata method call that goes through an implicit `__index` function
+fn userdata_call_method_complex(c: &mut Criterion) {
+    struct UserData(u64);
+    impl LuaUserData for UserData {
+        fn register(registry: &mut LuaUserDataRegistry<Self>) {
+            registry.add_field_method_get("val", |_, this| Ok(this.0));
+            registry.add_method_mut("inc_by", |_, this, by: u64| {
+                this.0 += by;
+                Ok(this.0)
+            });
+        }
+    }
+
+    let lua = Lua::new();
+    let ud = lua.create_userdata(UserData(0)).unwrap();
+    let inc_by = lua
+        .load("function(ud, s) return ud:inc_by(s) end")
+        .eval::<LuaFunction>()
+        .unwrap();
+
+    c.bench_function("userdata [call method complex]", |b| {
+        b.iter_batched(
+            || {
+                collect_gc_twice(&lua);
+            },
+            |_| {
+                inc_by.call::<()>((&ud, 1)).unwrap();
+            },
+            BatchSize::SmallInput,
+        );
+    });
+}
+
+fn userdata_async_call_method(c: &mut Criterion) {
+    struct UserData(i64);
+    impl LuaUserData for UserData {
+        fn add_methods<M: LuaUserDataMethods<Self>>(methods: &mut M) {
+            methods.add_async_method("add", |_, this, i: i64| async move {
+                task::yield_now().await;
+                Ok(this.0 + i)
+            });
+        }
+    }
+
+    let options = LuaOptions::new().thread_pool_size(1024);
+    let lua = Lua::new_with(LuaStdLib::ALL_SAFE, options).unwrap();
+    let ud = lua.create_userdata(UserData(123)).unwrap();
+    let method = lua
+        .load("function(ud, i) return ud:add(i) end")
+        .eval::<LuaFunction>()
+        .unwrap();
+    let i = AtomicUsize::new(0);
+
+    c.bench_function("userdata [async call method] 10", |b| {
+        let rt = Runtime::new().unwrap();
+        b.to_async(rt).iter_batched(
+            || {
+                collect_gc_twice(&lua);
+                (method.clone(), ud.clone(), i.fetch_add(1, Ordering::Relaxed))
+            },
+            |(method, ud, i)| async move {
+                assert_eq!(method.call_async::<usize>((ud, i)).await.unwrap(), 123 + i);
             },
             BatchSize::SmallInput,
         );
@@ -194,17 +437,34 @@ fn create_userdata(c: &mut Criterion) {
 criterion_group! {
     name = benches;
     config = Criterion::default()
-        .sample_size(200)
+        .sample_size(500)
+        .measurement_time(Duration::from_secs(10))
         .noise_threshold(0.02);
     targets =
-        create_table,
-        create_array,
-        create_string_table,
-        call_add_function,
-        call_add_callback,
-        call_append_callback,
-        create_registry_values,
-        create_userdata,
+        table_create_empty,
+        table_create_array,
+        table_create_hash,
+        table_get_set,
+        table_traversal_pairs,
+        table_traversal_for_each,
+        table_traversal_sequence,
+        table_ref_clone,
+
+        function_create,
+        function_call_sum,
+        function_call_lua_sum,
+        function_call_concat,
+        function_call_lua_concat,
+        function_async_call_sum,
+
+        registry_value_create,
+        registry_value_get,
+
+        userdata_create,
+        userdata_call_index,
+        userdata_call_method,
+        userdata_call_method_complex,
+        userdata_async_call_method,
 }
 
 criterion_main!(benches);

benches/serde.rs

@@ -0,0 +1,90 @@
+use std::time::Duration;
+
+use criterion::{criterion_group, criterion_main, BatchSize, Criterion};
+
+use mlua::prelude::*;
+
+fn collect_gc_twice(lua: &Lua) {
+    lua.gc_collect().unwrap();
+    lua.gc_collect().unwrap();
+}
+
+fn encode_json(c: &mut Criterion) {
+    let lua = Lua::new();
+
+    let encode = lua
+        .create_function(|_, t: LuaValue| Ok(serde_json::to_string(&t).unwrap()))
+        .unwrap();
+    let table = lua
+        .load(
+            r#"{
+        name = "Clark Kent",
+        address = {
+            city = "Smallville",
+            state = "Kansas",
+            country = "USA",
+        },
+        age = 22,
+        parents = {"Jonathan Kent", "Martha Kent"},
+        superman = true,
+        interests = {"flying", "saving the world", "kryptonite"},
+    }"#,
+        )
+        .eval::<LuaTable>()
+        .unwrap();
+
+    c.bench_function("serialize json", |b| {
+        b.iter_batched(
+            || collect_gc_twice(&lua),
+            |_| {
+                encode.call::<LuaString>(&table).unwrap();
+            },
+            BatchSize::SmallInput,
+        );
+    });
+}
+
+fn decode_json(c: &mut Criterion) {
+    let lua = Lua::new();
+
+    let decode = lua
+        .create_function(|lua, s: String| {
+            lua.to_value(&serde_json::from_str::<serde_json::Value>(&s).unwrap())
+        })
+        .unwrap();
+    let json = r#"{
+        "name": "Clark Kent",
+        "address": {
+            "city": "Smallville",
+            "state": "Kansas",
+            "country": "USA"
+        },
+        "age": 22,
+        "parents": ["Jonathan Kent", "Martha Kent"],
+        "superman": true,
+        "interests": ["flying", "saving the world", "kryptonite"]
+    }"#;
+
+    c.bench_function("deserialize json", |b| {
+        b.iter_batched(
+            || collect_gc_twice(&lua),
+            |_| {
+                decode.call::<LuaTable>(json).unwrap();
+            },
+            BatchSize::SmallInput,
+        );
+    });
+}
+
+criterion_group! {
+    name = benches;
+    config = Criterion::default()
+        .sample_size(500)
+        .measurement_time(Duration::from_secs(10))
+        .noise_threshold(0.02);
+    targets =
+        encode_json,
+        decode_json,
+}
+
+criterion_main!(benches);

build/find_normal.rs

@@ -1,106 +0,0 @@
-use std::env;
-use std::ffi::OsString;
-use std::fs::File;
-use std::io::{BufRead, BufReader, Result};
-use std::ops::Bound;
-use std::path::{Path, PathBuf};
-
-pub fn probe_lua() -> PathBuf {
-    let include_dir = env::var_os("LUA_INC").unwrap_or(OsString::new());
-    let lib_dir = env::var_os("LUA_LIB").unwrap_or(OsString::new());
-    let lua_lib = env::var_os("LUA_LIB_NAME").unwrap_or(OsString::new());
-
-    println!("cargo:rerun-if-env-changed=LUA_INC");
-    println!("cargo:rerun-if-env-changed=LUA_LIB");
-    println!("cargo:rerun-if-env-changed=LUA_LIB_NAME");
-    println!("cargo:rerun-if-env-changed=LUA_LINK");
-
-    if include_dir != "" && lib_dir != "" && lua_lib != "" {
-        let _version = use_custom_lua(&include_dir, &lib_dir, &lua_lib).unwrap();
-        return PathBuf::from(include_dir);
-    }
-
-    // Find using via pkg-config
-
-    #[cfg(feature = "lua53")]
-    {
-        let mut lua = pkg_config::Config::new()
-            .range_version((Bound::Included("5.3"), Bound::Excluded("5.4")))
-            .probe("lua");
-
-        if lua.is_err() {
-            lua = pkg_config::Config::new().probe("lua5.3");
-        }
-
-        return lua.unwrap().include_paths[0].clone();
-    }
-
-    #[cfg(feature = "lua52")]
-    {
-        let mut lua = pkg_config::Config::new()
-            .range_version((Bound::Included("5.2"), Bound::Excluded("5.3")))
-            .probe("lua");
-
-        if lua.is_err() {
-            lua = pkg_config::Config::new().probe("lua5.2");
-        }
-
-        return lua.unwrap().include_paths[0].clone();
-    }
-
-    #[cfg(feature = "lua51")]
-    {
-        let mut lua = pkg_config::Config::new()
-            .range_version((Bound::Included("5.1"), Bound::Excluded("5.2")))
-            .probe("lua");
-
-        if lua.is_err() {
-            lua = pkg_config::Config::new().probe("lua5.1");
-        }
-
-        return lua.unwrap().include_paths[0].clone();
-    }
-
-    #[cfg(feature = "luajit")]
-    {
-        let lua = pkg_config::Config::new()
-            .range_version((Bound::Included("2.1.0"), Bound::Unbounded))
-            .probe("luajit");
-
-        return lua.unwrap().include_paths[0].clone();
-    }
-}
-
-fn use_custom_lua<S: AsRef<Path>>(include_dir: &S, lib_dir: &S, lua_lib: &S) -> Result<String> {
-    let mut version_found = String::new();
-
-    // Find LUA_VERSION_NUM
-    let mut lua_h_path = include_dir.as_ref().to_owned();
-    lua_h_path.push("lua.h");
-    let f = File::open(lua_h_path)?;
-    let reader = BufReader::new(f);
-    for line in reader.lines() {
-        let line = line?;
-        let parts = line.split_whitespace().collect::<Vec<_>>();
-        if parts.len() == 3 && parts[1] == "LUA_VERSION_NUM" {
-            version_found = parts[2].to_string();
-        }
-    }
-
-    let mut link_lib = String::new();
-    if env::var("LUA_LINK").unwrap_or(String::new()) == "static" {
-        link_lib = "static=".to_string();
-    }
-
-    println!(
-        "cargo:rustc-link-search=native={}",
-        lib_dir.as_ref().display()
-    );
-    println!(
-        "cargo:rustc-link-lib={}{}",
-        link_lib,
-        lua_lib.as_ref().display()
-    );
-
-    Ok(version_found)
-}

build/find_vendored.rs

@@ -1,20 +0,0 @@
-use std::path::PathBuf;
-
-#[cfg(any(feature = "lua53", feature = "lua52", feature = "lua51"))]
-use lua_src;
-#[cfg(feature = "luajit")]
-use luajit_src;
-
-pub fn probe_lua() -> PathBuf {
-    #[cfg(feature = "lua53")]
-    let artifacts = lua_src::Build::new().build(lua_src::Lua53);
-    #[cfg(feature = "lua52")]
-    let artifacts = lua_src::Build::new().build(lua_src::Lua52);
-    #[cfg(feature = "lua51")]
-    let artifacts = lua_src::Build::new().build(lua_src::Lua51);
-    #[cfg(feature = "luajit")]
-    let artifacts = luajit_src::Build::new().build();
-
-    artifacts.print_cargo_metadata();
-    artifacts.include_dir().to_owned()
-}

build/main.rs

@@ -1,86 +0,0 @@
-#![allow(unreachable_code)]
-
-use std::env;
-use std::io::{Error, ErrorKind, Result};
-use std::path::{Path, PathBuf};
-use std::process::Command;
-
-#[cfg_attr(feature = "vendored", path = "find_vendored.rs")]
-#[cfg_attr(not(feature = "vendored"), path = "find_normal.rs")]
-mod find;
-
-trait CommandExt {
-    fn execute(&mut self) -> Result<()>;
-}
-
-impl CommandExt for Command {
-    /// Execute the command and return an error if it exited with a failure status.
-    fn execute(&mut self) -> Result<()> {
-        self.status()
-            .and_then(|status| {
-                if status.success() {
-                    Ok(())
-                } else {
-                    Err(Error::new(ErrorKind::Other, "non-zero exit code"))
-                }
-            })
-            .map_err(|_| {
-                Error::new(
-                    ErrorKind::Other,
-                    format!("The command {:?} did not run successfully.", self),
-                )
-            })
-    }
-}
-
-fn build_glue<P: AsRef<Path> + std::fmt::Debug>(include_path: &P) {
-    let build_dir = PathBuf::from(env::var_os("OUT_DIR").unwrap());
-
-    let mut config = cc::Build::new();
-    config.include(include_path);
-
-    // Compile and run glue.c
-    let glue = build_dir.join("glue");
-
-    config
-        .get_compiler()
-        .to_command()
-        .arg("src/ffi/glue/glue.c")
-        .arg("-o")
-        .arg(&glue)
-        .execute()
-        .unwrap();
-
-    Command::new(glue)
-        .arg(build_dir.join("glue.rs"))
-        .execute()
-        .unwrap();
-}
-
-fn main() {
-    #[cfg(not(any(
-        feature = "lua53",
-        feature = "lua52",
-        feature = "lua51",
-        feature = "luajit"
-    )))]
-    panic!("You must enable one of the features: lua53, lua52, lua51, luajit");
-
-    #[cfg(all(
-        feature = "lua53",
-        any(feature = "lua52", feature = "lua51", feature = "luajit")
-    ))]
-    panic!("You can enable only one of the features: lua53, lua52, lua51, luajit");
-
-    #[cfg(all(feature = "lua52", any(feature = "lua51", feature = "luajit")))]
-    panic!("You can enable only one of the features: lua53, lua52, lua51, luajit");
-
-    #[cfg(all(feature = "lua51", feature = "luajit"))]
-    panic!("You can enable only one of the features: lua53, lua52, lua51, luajit");
-
-    #[cfg(all(feature = "lua51", feature = "luajit"))]
-    panic!("You can enable only one of the features: lua53, lua52, lua51, luajit");
-
-    let include_dir = find::probe_lua();
-    build_glue(&include_dir);
-}

codecov.yml

@@ -0,0 +1,8 @@
+coverage:
+  status:
+    patch:
+      default:
+        only_pulls: true
+    project:
+      default:
+        only_pulls: true

docs/release_notes/v0.10.md

@@ -0,0 +1,195 @@
+## mlua v0.10 release notes
+
+The v0.10 version of mlua has goal to improve the user experience while keeping the same performance and safety guarantees.
+This document highlights the most notable features. For a full list of changes, see the [CHANGELOG].
+
+[CHANGELOG]: https://github.com/mlua-rs/mlua/blob/main/CHANGELOG.md
+
+### New features
+
+#### `'static` Lua types
+
+In previous mlua versions, it was required to have a `'lua` lifetime attached to every Lua value. v0.9 introduced (experimental) owned types that are `'static` without a lifetime attached, but they kept strong references to the Lua instance.
+In v0.10 all Lua types are `'static` and have only weak reference to the Lua instance. It means they are more flexible and can be used in more places without worrying about memory leaks.
+
+#### Truly `send` feature
+
+In this version Lua is `Send + Sync` when the `send` feature flag is enabled (previously was only `Send`). It means Lua instance and their values can be safely shared between threads and used in multi threaded async contexts.
+
+```rust
+let lua = Lua::new();
+
+lua.globals().set("i", 0)?;
+let func = lua.load("i = i + ...").into_function()?;
+
+std::thread::scope(|s| {
+    s.spawn(|| {
+        for i in 0..5 {
+            func.call::<()>(i).unwrap();
+        }
+    });
+    s.spawn(|| {
+        for i in 0..5 {
+            func.call::<()>(i).unwrap();
+        }
+    });
+});
+
+assert_eq!(lua.globals().get::<i32>("i")?, 20);
+```
+
+Under the hood, to synchronize access to the Lua state, mlua uses [`ReentrantMutex`] which can be recursively locked by a single thread. Only one thread can execute Lua code at a time, but it's possible to share Lua values between threads.
+
+This has some performance penalties (about 10-20%) compared to the lock free mode. This flag is disabled by default and does not supported in module mode.
+
+[`ReentrantMutex`]: https://docs.rs/parking_lot/latest/parking_lot/type.ReentrantMutex.html
+
+#### Register Rust functions with variable number of arguments
+
+The new traits `LuaNativeFn`/`LuaNativeFnMut`/`LuaNativeAsyncFn` have been introduced to provide a way to register Rust functions with variable number of arguments in Lua, without needing to pass all arguments as a tuple.
+
+They are used by `Function::wrap`/`Function::wrap_mut`/`Function::wrap_async` methods:
+
+```rust
+let add = Function::wrap(|a: i64, b: i64| Ok(a + b));
+
+lua.globals().set("add", add).unwrap();
+
+// Prints 50
+lua.load(r#"print(add(5, 45))"#).exec().unwrap();
+```
+
+To wrap functions that return direct value (non-`Result`) you can use `Function::wrap_raw` method.
+
+#### Setting metatable for Lua builtin types
+
+For Lua builtin types (like `string`, `function`, `number`, etc.) that have a shared metatable for all instances, it's now possible to set a custom metatable for them.
+
+```rust
+let mt = lua.create_table()?;
+mt.set("__tostring", lua.create_function(|_, b: bool| Ok(if b { "2" } else { "0" }))?)?;
+lua.set_type_metatable::<bool>(Some(mt));
+lua.load("assert(tostring(true) == '2')").exec().unwrap();
+```
+
+### Improvements
+
+#### New `ObjectLike` trait
+
+The `ObjectLike` trait is a combination of the `AnyUserDataExt` and `TableExt` traits used in previous versions. It provides a unified interface for working with Lua tables and userdata.
+
+#### `Either<L, R>` enum
+
+The `Either<L, R>` enum is a simple enum that can hold either `L` or `R` value. It's useful when you need to return or receive one of two types in a function.
+This type implements `IntoLua` and `FromLua` traits and can generate a meaningful error message when conversion fails.
+
+```rust
+let func = Function::wrap(|x: Either<i32, String>| Ok(format!("received: {x}")));
+
+lua.globals().set("func", func).unwrap();
+
+// Prints: received: 123
+lua.load(r#"print(func(123))"#).exec().unwrap();
+
+// Prints: bad argument #1: error converting Lua table to Either<i32, String>
+lua.load(r#"print(pcall(func, {}))"#).exec().unwrap();
+```
+
+#### `Lua::exec_raw` helper to execute low-level Lua C API code
+
+For advanced users, it's now possible to execute low-level Lua C API code using the `Lua::exec_raw` method.
+
+```rust
+let t = lua.create_sequence_from([1, 2, 3, 4, 5])?;
+let sum: i64 = unsafe {
+    lua.exec_raw(&t, |state| {
+        // top of the stack: table `t`
+        let mut sum = 0;
+        // push nil as the first key
+        mlua::ffi::lua_pushnil(state);
+        while mlua::ffi::lua_next(state, -2) != 0 {
+            sum += mlua::ffi::lua_tointeger(state, -1);
+            // Remove the value, keep the key for the next iteration
+            mlua::ffi::lua_pop(state, 1);
+        }
+        mlua::ffi::lua_pop(state, 1);
+        mlua::ffi::lua_pushinteger(state, sum);
+        // top of the stack: sum
+    })
+}?;
+assert_eq!(sum, 15);
+```
+
+The `exec_raw` method is longjmp-safe. It's not recommended to move `Drop` types into the closure to avoid possible memory leaks.
+
+#### `anyhow` feature flag
+
+The new `anyhow` feature flag adds `IntoLua` and `Into<mlua::Error>` implementation for the `anyhow::Error` type.
+
+```rust
+let f = lua.create_function(|_, ()| {
+    Err(anyhow!("error message"))?;
+    Ok(())
+})?;
+```
+
+### Breaking changes
+
+#### Scope changes
+
+The following `Scope` methods were changed:
+- Removed `Scope::create_any_userdata`
+- `Scope::create_nonstatic_userdata` is renamed to `Scope::create_userdata`
+
+Instead, scope has comprehensive support for borrowed userdata: `create_any_userdata_ref`, `create_any_userdata_ref_mut`, `create_userdata_ref`, `create_userdata_ref_mut`.
+
+`UserDataRef` and `UserDataRefMut` are no longer acceptable for scoped userdata access as they require owned underlying data.
+In mlua v0.9 this can cause read-after-free bug in some edge cases.
+
+To temporarily borrow underlying data, the `AnyUserData::borrow_scoped` and `AnyUserData::borrow_mut_scoped` methods were introduced:
+
+```rust
+let data = "hello".to_string();
+lua.scope(|scope| {
+    let ud = scope.create_any_userdata_ref(&data)?;
+
+    // We can only borrow scoped userdata using this method
+    ud.borrow_scoped::<String, ()>(|s| {
+        assert_eq!(s, "hello");
+    })?;
+
+    Ok(())
+})?;
+```
+
+Those methods work for scoped and regular userdata objects (but still require `T: 'static`).
+
+#### String changes
+
+Since `mlua::String` holds a weak reference to Lua without any guarantees about the lifetime of the underlying data, getting a `&str` or `&[u8]` from it is no longer safe.
+Lua instance can be destroyed while reference to the data is still alive:
+
+```rust
+let lua = Lua::new();
+let s: mlua::String = lua.create_string("hello, world")?; // only weak reference to Lua!
+let s_ref: &str = s.to_str()?; // this is not safe!
+drop(lua);
+println!("{s_ref}"); // use after free!
+```
+
+To solve this issue, return types of `mlua::String::to_str` and `mlua::String::as_bytes` methods changed to `BorrowedStr` and `BorrowedBytes` respectively.
+
+These new types hold a strong reference to the Lua instance and can be safely converted to `&str` or `&[u8]`:
+
+```rust
+let lua = Lua::new();
+let s: mlua::String = lua.create_string("hello, world")?;
+let s_ref: mlua::BorrowedStr = s.to_str()?; // The strong reference to Lua is held here
+drop(lua);
+println!("{s_ref}"); // ok
+```
+
+The good news is that `BorrowedStr` implements `Deref<Target = str>`/`AsRef<str>` as well as `Display`, `Debug`, `Eq`, `PartialEq` and other traits for easy usage.
+The same applies to `BorrowedBytes`.
+
+Unfortunately, `mlua::String::to_string_lossy` cannot return `Cow<'a, str>` anymore, because it requires a strong reference to Lua. It now returns Rust `String` instead.

docs/release_notes/v0.9.md

@@ -0,0 +1,361 @@
+## mlua v0.9 release notes
+
+The v0.9 version of mlua is a major release that includes a number of API changes and improvements. This release is a stepping stone towards the v1.0.
+This document highlights the most important changes. For a full list of changes, see the [CHANGELOG].
+
+[CHANGELOG]: https://github.com/mlua-rs/mlua/blob/main/CHANGELOG.md
+
+### New features
+
+#### 1. New Any UserData API
+
+This is a long awaited feature that allows to register in Lua foreign types that cannot implement `UserData` trait because of the Rust orphan rules.
+
+Now you can register any type that implements [`Any`] trait as a userdata type.
+
+Consider the following example:
+
+```rust
+lua.register_userdata_type::<std::string::String>(|reg| {
+    reg.add_method("len", |_, this, ()| Ok(this.len()));
+
+    reg.add_method_mut("push", |_, this, s: String| {
+        this.push_str(&s);
+        Ok(())
+    });
+
+    reg.add_meta_method(MetaMethod::ToString, |lua, this, ()| lua.create_string(this));
+})?;
+
+let s = lua.create_any_userdata("hello".to_string())?;
+lua.load(chunk! {
+    print("s:len() is " .. $s:len())
+    $s:push(" world")
+    // Prints: hello, world
+    print($s)
+})
+.exec()?;
+```
+
+In this example we registered [`std::string::String`] as a userdata type with a set of methods and then created an instance of this type in Lua.
+
+It's _not_ required to register a type before using the `Lua::create_any_userdata()` method, instead an empty metatable will be created for you.
+You can also register the same type multiple times with different methods. Any previously created instances will share the old metatable, while new instances will have the new one.
+
+The new set of API is called `any_userdata` because it allows to register types that implements [`Any`] trait.
+
+[`std::string::String`]: https://doc.rust-lang.org/stable/std/string/struct.String.html
+[`Any`]: https://doc.rust-lang.org/stable/std/any/trait.Any.html
+
+#### 2. Scope support for the new any userdata types
+
+When you need to create non-static userdata instances in Lua, the usual way is use `Lua::scope()` helper to make them scoped. When out of scope, any scoped objects will be automatically
+dropped. The only downside of this approach is that every new instance will have a new metatable. This is not very fast if you need to create a lot of instances.
+
+With the new Any UserData API, you can place non-static references `&T` where `T: 'static` into a scope and they will share a single static metatable.
+
+```rust
+lua.register_userdata_type::<std::string::String>(|reg| {
+    reg.add_method_mut("replace", |_, this, (pat, to): (String, String)| {
+        *this = this.replace(&pat, &to);
+        Ok(())
+    });
+
+    reg.add_meta_method(MetaMethod::ToString, |lua, this, ()| lua.create_string(this));
+})?;
+
+let mut s = "hello, world".to_string();
+
+lua.scope(|scope| {
+    // This userdata instance holds only a mutable reference to our string
+    let ud = scope.create_any_userdata_ref_mut(&mut s)?;
+    lua.load(chunk! {
+        $ud:replace("world", "user")
+    })
+    .exec()
+})?;
+
+// Prints: hello, user!
+println!("{s}!");
+```
+
+#### 3. Owned types (`unstable`)
+
+One of the common questions was how to embed a Lua type into Rust struct to use it later. It was non-trivial to do because of the `'lua` lifetime attached to every Lua value.
+
+In v0.9 mlua introduces "owned" types `OwnedTable`/`OwnedFunction`/`OwnedString`/`OwnedAnyUserData`/ `OwnedThread`that are `'static` (no lifetime attached).
+
+```rust
+let lua = Lua::new();
+
+struct MyStruct {
+    table: OwnedTable,
+    func: OwnedFunction,
+}
+
+let my_struct = MyStruct {
+    table: lua.globals().into_owned(),
+    func: lua
+        .create_function(|_, t: Table| Ok(format!("{t:#?}")))?
+        .into_owned(),
+};
+
+// It's safe to drop Lua!
+drop(lua);
+
+let result = my_struct.func.call::<_, String>(my_struct.table)?;
+println!("{result}");
+```
+
+Prior to v0.9, it was possible to do by creating a reference to the Lua value in registry using `Lua::create_registry_value()`
+and retrieving value later using `Lua::registry_value()` method.
+
+All owned handles hold a *strong* reference to the current Lua instance.
+Be warned, if you place them into a Lua type (eg. `UserData` or a Rust callback), it is *very easy*
+to accidentally cause reference cycles that would prevent destroying Lua instance.
+
+Please note this functionality is available under the `unstable` feature flag and not available when the `send` feature is enabled.
+
+#### New ffi module
+
+In v0.9 release the internal `ffi` module has been moved into the new [`mlua-sys`] crate and became available for public use.
+This crate provides unified Lua FFI API (targeting Lua 5.4) using a (limited) compatibility layer for older versions.
+
+mlua re-exports the `ffi` module aliasing the `mlua-sys` crate and provides (unsafe) functionality to work with raw Lua state:
+
+```rust
+unsafe {
+    unsafe extern "C-unwind" fn lua_add(state: *mut mlua::lua_State) -> i32 {
+        let a = mlua::ffi::luaL_checkinteger(state, 1);
+        let b = mlua::ffi::luaL_checkinteger(state, 2);
+        mlua::ffi::lua_pushinteger(state, a + b);
+        1
+    }
+
+    let add = lua.create_c_function(lua_add)?;
+    assert_eq!(add.call::<_, i32>((2, 3))?, 5);
+}
+```
+
+[`mlua-sys`]: https://crates.io/crates/mlua-sys
+
+#### Luau JIT support
+
+mlua brings support for the new [Luau] JIT backend under the `luau-jit` feature flag.
+
+It will automatically trigger JIT compilation for new Lua chunks. To disable it, just call `lua.enable_jit(false)` before loading Lua code
+(but any previously compiled chunks will remain JIT-compiled).
+
+[Luau]: https://luau-lang.org
+
+### Improvements
+
+#### 1. Better error reporting
+
+When calling a Rust function from Lua and passing wrong arguments, previous mlua versions reported a error message without any context or reference to the particular argument.
+
+In v0.9 it reports a error message with the argument index and expected type:
+
+```rust
+let func = lua.create_function(|_, _a: i32| Ok(()))?;
+lua.load(chunk! {
+    local ok, err = pcall($func, "not a number")
+    // Prints: bad argument #1: error converting Lua string to i32 (expected number or string coercible to number)
+    print(err)
+})
+.exec()?;
+```
+
+Similar changes have been made for userdata functions and methods:
+
+```rust
+lua.register_userdata_type::<&'static str>(|reg| {
+    reg.add_method("len", |_, this, ()| Ok(this.len()));
+})?;
+
+let s = lua.create_any_userdata("hello")?;
+lua.load(chunk! {
+    local ok, err = pcall($s.len, 123)
+    // Prints: bad argument `self` to `&str.len`: error converting Lua integer to userdata
+    print(err)
+})
+.exec()?;
+```
+
+#### 2. Error context
+
+Similar to the [`anyhow`] Error type, now it's possible to attach context to Lua errors:
+
+```rust
+let read = lua.create_function(|lua, path: String| {
+    let bytes = std::fs::read(&path)
+        .into_lua_err()
+        .context(format!("Failed to open `{path}`"))?;
+    Ok(lua.create_string(bytes))
+})?;
+
+lua.load(chunk! {
+    local ok, err = pcall($read, "/nonexistent")
+    /// Prints:
+    /// Failed to open /nonexistent
+    /// No such file or directory (os error 2)
+    /// stack traceback:
+    /// ...
+    print(err)
+})
+.exec()?;
+```
+
+[`anyhow`]: https://crates.io/crates/anyhow
+
+#### 4. New methods `Function::wrap`/`AnyUserData::wrap`
+
+Sometimes it's useful to have `IntoLua` trait implementation for a Rust function or type `T: Any` without needing to call `Lua::create_function()`/`Lua::create_any_userdata()` methods.
+Since v0.9 you can call the new methods `Function::wrap()`/`AnyUserData::wrap()` that allows to do this. They return an abstract type that `impl IntoLua`:
+
+```rust
+lua.globals().set("print_rust", Function::wrap(|_, s: String| Ok(println!("{}", s))))?;
+lua.globals().set("rust_ud", AnyUserData::wrap("hello"))?;
+```
+
+In addition there are also `Function::wrap_mut()`/`Function::wrap_async()` methods that allow to wrap mutable and async functions respectively.
+
+For a `T: 'UserData + 'static` the `IntoLua` trait is still always implemented.
+
+#### `UserDataRef` and `UserDataRefMut` type wrappers
+
+The new wrappers `UserDataRef` and `UserDataRefMut` are receivers for userdata type `T` and borrow underlying instance for the lifetime of the wrapper.
+
+```rust
+lua.globals()
+    .set("ud", AnyUserData::wrap("hello".to_string()))?;
+
+let mut ud_mut: UserDataRefMut<String> = lua.globals().get("ud")?;
+ud_mut.push_str(", Rust");
+drop(ud_mut);
+
+let ud_ref: UserDataRef<String> = lua.globals().get("ud")?;
+// Prints: hello, Rust
+println!("{}", *ud_ref);
+```
+
+In the previous mlua versions the same functionality can be achieved by receiving `AnyUserData` and calling `AnyUserData::borrow()`/`AnyUserData::borrow_mut()` methods.
+
+The new wrappers are identical to Rust [`Ref`]/[`RefMut`] types.
+
+[`Ref`]: https://doc.rust-lang.org/std/cell/struct.Ref.html
+[`RefMut`]: https://doc.rust-lang.org/std/cell/struct.RefMut.html
+
+#### New `AnyUserDataExt` trait
+
+Similar to the `TableExt` trait, the `AnyUserDataExt` provides a set of extra methods for the `AnyUserData` type.
+
+1) `AnyUserDataExt::get()/set()` to get/set a value by key from the userdata, assuming it has `__index` metamethod.
+
+2) `AnyUserDataExt::call()` to call the userdata as a function assuming it has `__call` metamethod.
+
+3) `AnyUserData::call_method(name, ...)` to call the userdata method, assuming it has `__index` metamethod and the associated function.
+
+#### Pretty formatting Lua values
+
+`mlua::Value` implements a new format `:#?` that allows to (recursively) pretty print Lua values:
+
+```rust
+println!("{:#?}", lua.globals());
+```
+
+Prints:
+```
+{
+  ["_G"] = table: 0x7fa2d0706260,
+  ["_VERSION"] = "Lua 5.4",
+  ["assert"] = function: 0x10451d11d,
+  ["collectgarbage"] = function: 0x10451d198,
+  ["coroutine"] = {
+    ["close"] = function: 0x10451e28f,
+    ...
+  },
+  ["dofile"] = function: 0x10451d37c,
+  ...
+}
+```
+
+In addition a new method `Value::to_string()` has been added to convert `Value` to a string (using `__tostring` metamethod if available).
+
+#### Environment for Lua functions
+
+Any Lua functions have an associated environment table that is used to resolve global variables. By default it sets to a Lua globals table.
+
+In the new release it's possible to get or update a function environment using `Function::environment()` or `Function::set_environment()` methods respectively.
+
+```rust
+let f = lua.load("return a").into_function()?;
+
+assert_eq!(f.environment(), Some(lua.globals()));
+
+lua.globals().set("a", 1)?;
+assert_eq!(f.call::<_, i32>(())?, 1);
+
+f.set_environment(lua.create_table_from([("a", "hello")])?)?;
+assert_eq!(f.call::<_, mlua::String>(())?, "hello");
+```
+
+#### Performance optimizations
+
+The new mlua version has a number of performance improvements. Please check the [benchmarks results] to see how mlua compares to rlua and rhai.
+
+[benchmarks results]: https://github.com/mlua-rs/script-bench-rs
+
+### Changes in `module` mode
+
+#### New attributes
+
+The `lua_module` macro now support the following attributes:
+
+- `name=...` - sets name of the module (defaults to the name of the function).
+
+Eg.:
+
+```rust
+#[mlua::lua_module(name = "alt_module")]
+fn my_module(lua: &Lua) -> LuaResult<LuaTable> {
+    lua.create_table()
+}
+```
+
+Under the hood a new function `luaopen_alt_module` will be created for the Lua module loader.
+
+- `skip_memory_check` - skip memory allocation checks for some operations.
+
+In module mode, mlua runs in unknown environment and cannot say are there any memory limits or not. As result, some operations that require memory allocation runs in
+protected mode. Setting this attribute will improve performance of such operations with risk of having uncaught exceptions and memory leaks.
+
+#### Improved Windows target
+
+In previous mlua versions, building a Lua module for Windows requires having Lua development libraries installed on the system.
+In contrast, on Linux and macOS, modules can be built without any external dependencies using the `-undefined=dynamic_lookup` linker flag.
+
+With Rust 1.71+ it's now possible to lift this restriction for Windows as well. You can build modules normally and they will be linked with
+`lua54.dll`/`lua53.dll`/`lua52.dll`/`lua51.dll` depending on the enabled Lua version.
+
+You still need to have the dll although, linked to application where the module will be loaded.
+
+### Breaking changes
+
+1) `ToLua`/`ToLuaMulti` traits have been renamed to `IntoLua`/`IntoLuaMulti` respectively (with the methods called `into_lua`/`into_lua_multi`).
+
+The main reason for this change is following the Rust self [convention](https://rust-lang.github.io/rust-clippy/master/index.html#/wrong_self_convention).
+
+2) Removed `FromLua` implementation for `T: UserData + Clone`.
+
+During the usage of mlua, it was found that this implementation is not very useful and prevents custom `FromLua` implementations for `T: UserData`.
+It should be a developer decision to opt-in `FromLua` for their `T` if needed rather than having enabled it unconditionally.
+
+To opt-in `FromLua` for `T: Clone` you can use a simple `#[derive(FromLua)]` macro (requires `feature = "macros"`):
+
+```rust
+#[derive(Clone, Copy, mlua::FromLua)]
+struct MyUserData(i32);
+```
+
+`T` is not required to implement `UserData` because of the new relaxed restrictions on userdata types.

examples/async_http_client.rs

@@ -0,0 +1,71 @@
+use std::collections::HashMap;
+
+use http_body_util::BodyExt as _;
+use hyper::body::Incoming;
+use hyper_util::client::legacy::Client as HyperClient;
+use hyper_util::rt::TokioExecutor;
+
+use mlua::{chunk, ExternalResult, Lua, Result, UserData, UserDataMethods};
+
+struct BodyReader(Incoming);
+
+impl UserData for BodyReader {
+    fn add_methods<M: UserDataMethods<Self>>(methods: &mut M) {
+        // Every call returns a next chunk
+        methods.add_async_method_mut("read", |lua, mut reader, ()| async move {
+            if let Some(bytes) = reader.0.frame().await {
+                if let Some(bytes) = bytes.into_lua_err()?.data_ref() {
+                    return Some(lua.create_string(&bytes)).transpose();
+                }
+            }
+            Ok(None)
+        });
+    }
+}
+
+#[tokio::main(flavor = "current_thread")]
+async fn main() -> Result<()> {
+    let lua = Lua::new();
+
+    let fetch_url = lua.create_async_function(|lua, uri: String| async move {
+        let client = HyperClient::builder(TokioExecutor::new()).build_http::<String>();
+        let uri = uri.parse().into_lua_err()?;
+        let resp = client.get(uri).await.into_lua_err()?;
+
+        let lua_resp = lua.create_table()?;
+        lua_resp.set("status", resp.status().as_u16())?;
+
+        let mut headers = HashMap::new();
+        for (key, value) in resp.headers() {
+            headers
+                .entry(key.as_str())
+                .or_insert(Vec::new())
+                .push(value.to_str().into_lua_err()?);
+        }
+
+        lua_resp.set("headers", headers)?;
+        lua_resp.set("body", BodyReader(resp.into_body()))?;
+
+        Ok(lua_resp)
+    })?;
+
+    let f = lua
+        .load(chunk! {
+            local res = $fetch_url(...)
+            print("status: "..res.status)
+            for key, vals in pairs(res.headers) do
+                for _, val in ipairs(vals) do
+                    print(key..": "..val)
+                end
+            end
+            repeat
+                local chunk = res.body:read()
+                if chunk then
+                    print(chunk)
+                end
+            until not chunk
+        })
+        .into_function()?;
+
+    f.call_async("http://httpbin.org/ip").await
+}

examples/async_http_reqwest.rs

@@ -0,0 +1,29 @@
+use mlua::{chunk, ExternalResult, Lua, LuaSerdeExt, Result, Value};
+
+#[tokio::main(flavor = "current_thread")]
+async fn main() -> Result<()> {
+    let lua = Lua::new();
+
+    let fetch_json = lua.create_async_function(|lua, uri: String| async move {
+        let resp = reqwest::get(&uri)
+            .await
+            .and_then(|resp| resp.error_for_status())
+            .into_lua_err()?;
+        let json = resp.json::<serde_json::Value>().await.into_lua_err()?;
+        lua.to_value(&json)
+    })?;
+
+    let dbg = lua.create_function(|_, value: Value| {
+        println!("{value:#?}");
+        Ok(())
+    })?;
+
+    let f = lua
+        .load(chunk! {
+            local res = $fetch_json(...)
+            $dbg(res)
+        })
+        .into_function()?;
+
+    f.call_async("https://httpbin.org/anything?arg0=val0").await
+}

examples/async_http_server.rs

@@ -0,0 +1,128 @@
+use std::convert::Infallible;
+use std::future::Future;
+use std::net::SocketAddr;
+use std::pin::Pin;
+
+use http_body_util::combinators::BoxBody;
+use http_body_util::{BodyExt as _, Empty, Full};
+use hyper::body::{Bytes, Incoming};
+use hyper::server::conn::http1;
+use hyper::{Request, Response};
+use hyper_util::rt::TokioIo;
+use tokio::net::TcpListener;
+
+use mlua::{chunk, Error as LuaError, Function, Lua, String as LuaString, Table, UserData, UserDataMethods};
+
+/// Wrapper around incoming request that implements UserData
+struct LuaRequest(SocketAddr, Request<Incoming>);
+
+impl UserData for LuaRequest {
+    fn add_methods<M: UserDataMethods<Self>>(methods: &mut M) {
+        methods.add_method("remote_addr", |_, req, ()| Ok((req.0).to_string()));
+        methods.add_method("method", |_, req, ()| Ok((req.1).method().to_string()));
+        methods.add_method("path", |_, req, ()| Ok(req.1.uri().path().to_string()));
+    }
+}
+
+/// Service that handles incoming requests
+#[derive(Clone)]
+pub struct Svc {
+    handler: Function,
+    peer_addr: SocketAddr,
+}
+
+impl Svc {
+    pub fn new(handler: Function, peer_addr: SocketAddr) -> Self {
+        Self { handler, peer_addr }
+    }
+}
+
+impl hyper::service::Service<Request<Incoming>> for Svc {
+    type Response = Response<BoxBody<Bytes, Infallible>>;
+    type Error = LuaError;
+    type Future = Pin<Box<dyn Future<Output = Result<Self::Response, Self::Error>> + Send>>;
+
+    fn call(&self, req: Request<Incoming>) -> Self::Future {
+        // If handler returns an error then generate 5xx response
+        let handler = self.handler.clone();
+        let lua_req = LuaRequest(self.peer_addr, req);
+        Box::pin(async move {
+            match handler.call_async::<Table>(lua_req).await {
+                Ok(lua_resp) => {
+                    let status = lua_resp.get::<Option<u16>>("status")?.unwrap_or(200);
+                    let mut resp = Response::builder().status(status);
+
+                    // Set headers
+                    if let Some(headers) = lua_resp.get::<Option<Table>>("headers")? {
+                        for pair in headers.pairs::<String, LuaString>() {
+                            let (h, v) = pair?;
+                            resp = resp.header(&h, &*v.as_bytes());
+                        }
+                    }
+
+                    // Set body
+                    let body = lua_resp
+                        .get::<Option<LuaString>>("body")?
+                        .map(|b| Full::new(Bytes::copy_from_slice(&b.as_bytes())).boxed())
+                        .unwrap_or_else(|| Empty::<Bytes>::new().boxed());
+
+                    Ok(resp.body(body).unwrap())
+                }
+                Err(err) => {
+                    eprintln!("{}", err);
+                    Ok(Response::builder()
+                        .status(500)
+                        .body(Full::new(Bytes::from("Internal Server Error")).boxed())
+                        .unwrap())
+                }
+            }
+        })
+    }
+}
+
+#[tokio::main(flavor = "current_thread")]
+async fn main() {
+    let lua = Lua::new();
+
+    // Create Lua handler function
+    let handler = lua
+        .load(chunk! {
+            function(req)
+                return {
+                    status = 200,
+                    headers = {
+                        ["X-Req-Method"] = req:method(),
+                        ["X-Req-Path"] = req:path(),
+                        ["X-Remote-Addr"] = req:remote_addr(),
+                    },
+                    body = "Hello from Lua!\n"
+                }
+            end
+        })
+        .eval::<Function>()
+        .expect("Failed to create Lua handler");
+
+    let listen_addr = "127.0.0.1:3000";
+    let listener = TcpListener::bind(listen_addr).await.unwrap();
+    println!("Listening on http://{listen_addr}");
+
+    loop {
+        let (stream, peer_addr) = match listener.accept().await {
+            Ok(x) => x,
+            Err(err) => {
+                eprintln!("Failed to accept connection: {err}");
+                continue;
+            }
+        };
+
+        let svc = Svc::new(handler.clone(), peer_addr);
+        tokio::task::spawn(async move {
+            if let Err(err) = http1::Builder::new()
+                .serve_connection(TokioIo::new(stream), svc)
+                .await
+            {
+                eprintln!("Error serving connection: {:?}", err);
+            }
+        });
+    }
+}

examples/async_tcp_server.rs

@@ -0,0 +1,91 @@
+use std::io;
+use std::net::SocketAddr;
+
+use tokio::io::{AsyncReadExt, AsyncWriteExt};
+use tokio::net::{TcpListener, TcpStream};
+
+use mlua::{chunk, BString, Function, Lua, UserData, UserDataMethods};
+
+struct LuaTcpStream(TcpStream);
+
+impl UserData for LuaTcpStream {
+    fn add_methods<M: UserDataMethods<Self>>(methods: &mut M) {
+        methods.add_method("peer_addr", |_, this, ()| Ok(this.0.peer_addr()?.to_string()));
+
+        methods.add_async_method_mut("read", |lua, mut this, size| async move {
+            let mut buf = vec![0; size];
+            let n = this.0.read(&mut buf).await?;
+            buf.truncate(n);
+            lua.create_string(&buf)
+        });
+
+        methods.add_async_method_mut("write", |_, mut this, data: BString| async move {
+            let n = this.0.write(&data).await?;
+            Ok(n)
+        });
+
+        methods.add_async_method_mut("close", |_, mut this, ()| async move {
+            this.0.shutdown().await?;
+            Ok(())
+        });
+    }
+}
+
+async fn run_server(handler: Function) -> io::Result<()> {
+    let addr: SocketAddr = ([127, 0, 0, 1], 3000).into();
+    let listener = TcpListener::bind(addr).await.expect("cannot bind addr");
+
+    println!("Listening on {}", addr);
+
+    loop {
+        let (stream, _) = match listener.accept().await {
+            Ok(res) => res,
+            Err(err) if is_transient_error(&err) => continue,
+            Err(err) => return Err(err),
+        };
+
+        let handler = handler.clone();
+        tokio::task::spawn(async move {
+            let stream = LuaTcpStream(stream);
+            if let Err(err) = handler.call_async::<()>(stream).await {
+                eprintln!("{}", err);
+            }
+        });
+    }
+}
+
+#[tokio::main(flavor = "current_thread")]
+async fn main() {
+    let lua = Lua::new();
+
+    // Create Lua handler function
+    let handler = lua
+        .load(chunk! {
+            function(stream)
+                local peer_addr = stream:peer_addr()
+                print("connected from "..peer_addr)
+
+                while true do
+                    local data = stream:read(100)
+                    data = data:match("^%s*(.-)%s*$") // trim
+                    print("["..peer_addr.."] "..data)
+                    if data == "bye" then
+                        stream:write("bye bye\n")
+                        stream:close()
+                        return
+                    end
+                    stream:write("echo: "..data.."\n")
+                end
+            end
+        })
+        .eval::<Function>()
+        .expect("cannot create Lua handler");
+
+    run_server(handler).await.expect("cannot run server")
+}
+
+fn is_transient_error(e: &io::Error) -> bool {
+    e.kind() == io::ErrorKind::ConnectionRefused
+        || e.kind() == io::ErrorKind::ConnectionAborted
+        || e.kind() == io::ErrorKind::ConnectionReset
+}

examples/guided_tour.rs

@@ -1,15 +1,15 @@
 use std::f32;
 use std::iter::FromIterator;
 
-use mlua::{Function, Lua, MetaMethod, Result, UserData, UserDataMethods, Variadic};
+use mlua::{chunk, FromLua, Function, Lua, MetaMethod, Result, UserData, UserDataMethods, Value, Variadic};
 
 fn main() -> Result<()> {
-    // You can create a new Lua state with `Lua::new()`.  This loads the default Lua std library
+    // You can create a new Lua state with `Lua::new()`. This loads the default Lua std library
     // *without* the debug library.
     let lua = Lua::new();
 
-    // You can get and set global variables.  Notice that the globals table here is a permanent
-    // reference to _G, and it is mutated behind the scenes as Lua code is loaded.  This API is
+    // You can get and set global variables. Notice that the globals table here is a permanent
+    // reference to _G, and it is mutated behind the scenes as Lua code is loaded. This API is
     // based heavily around sharing and internal mutation (just like Lua itself).
 
     let globals = lua.globals();
@@ -17,12 +17,12 @@ fn main() -> Result<()> {
     globals.set("string_var", "hello")?;
     globals.set("int_var", 42)?;
 
-    assert_eq!(globals.get::<_, String>("string_var")?, "hello");
-    assert_eq!(globals.get::<_, i64>("int_var")?, 42);
+    assert_eq!(globals.get::<String>("string_var")?, "hello");
+    assert_eq!(globals.get::<i64>("int_var")?, 42);
 
-    // You can load and evaluate Lua code.  The returned type of `Lua::load` is a builder
-    // that allows you to change settings before running Lua code.  Here, we are using it to set
-    // the name of the laoded chunk to "example code", which will be used when Lua error
+    // You can load and evaluate Lua code. The returned type of `Lua::load` is a builder
+    // that allows you to change settings before running Lua code. Here, we are using it to set
+    // the name of the loaded chunk to "example code", which will be used when Lua error
     // messages are printed.
 
     lua.load(
@@ -30,14 +30,25 @@ fn main() -> Result<()> {
             global = 'foo'..'bar'
         "#,
     )
-    .set_name("example code")?
+    .set_name("example code")
     .exec()?;
-    assert_eq!(globals.get::<_, String>("global")?, "foobar");
+    assert_eq!(globals.get::<String>("global")?, "foobar");
 
     assert_eq!(lua.load("1 + 1").eval::<i32>()?, 2);
     assert_eq!(lua.load("false == false").eval::<bool>()?, true);
     assert_eq!(lua.load("return 1 + 2").eval::<i32>()?, 3);
 
+    // Use can use special `chunk!` macro to use Rust tokenizer and automatically capture variables
+
+    let a = 1;
+    let b = 2;
+    let name = "world";
+    lua.load(chunk! {
+        print($a + $b)
+        print("hello, " .. $name)
+    })
+    .exec()?;
+
     // You can create and manage Lua tables
 
     let array_table = lua.create_table()?;
@@ -74,28 +85,28 @@ fn main() -> Result<()> {
     // You can load Lua functions
 
     let print: Function = globals.get("print")?;
-    print.call::<_, ()>("hello from rust")?;
+    print.call::<()>("hello from rust")?;
 
-    // This API generally handles variadics using tuples.  This is one way to call a function with
+    // This API generally handles variadic using tuples. This is one way to call a function with
     // multiple parameters:
 
-    print.call::<_, ()>(("hello", "again", "from", "rust"))?;
+    print.call::<()>(("hello", "again", "from", "rust"))?;
 
     // But, you can also pass variadic arguments with the `Variadic` type.
 
-    print.call::<_, ()>(Variadic::from_iter(
+    print.call::<()>(Variadic::from_iter(
         ["hello", "yet", "again", "from", "rust"].iter().cloned(),
     ))?;
 
-    // You can bind rust functions to Lua as well.  Callbacks receive the Lua state inself as their
-    // first parameter, and the arguments given to the function as the second parameter.  The type
+    // You can bind rust functions to Lua as well. Callbacks receive the Lua state itself as their
+    // first parameter, and the arguments given to the function as the second parameter. The type
     // of the arguments can be anything that is convertible from the parameters given by Lua, in
     // this case, the function expects two string sequences.
 
     let check_equal = lua.create_function(|_, (list1, list2): (Vec<String>, Vec<String>)| {
         // This function just checks whether two string lists are equal, and in an inefficient way.
         // Lua callbacks return `mlua::Result`, an Ok value is a normal return, and an Err return
-        // turns into a Lua 'error'.  Again, any type that is convertible to Lua may be returned.
+        // turns into a Lua 'error'. Again, any type that is convertible to Lua may be returned.
         Ok(list1 == list2)
     })?;
     globals.set("check_equal", check_equal)?;
@@ -140,8 +151,18 @@ fn main() -> Result<()> {
     #[derive(Copy, Clone)]
     struct Vec2(f32, f32);
 
+    // We can implement `FromLua` trait for our `Vec2` to return a copy
+    impl FromLua for Vec2 {
+        fn from_lua(value: Value, _: &Lua) -> Result<Self> {
+            match value {
+                Value::UserData(ud) => Ok(*ud.borrow::<Self>()?),
+                _ => unreachable!(),
+            }
+        }
+    }
+
     impl UserData for Vec2 {
-        fn add_methods<'lua, M: UserDataMethods<'lua, Self>>(methods: &mut M) {
+        fn add_methods<M: UserDataMethods<Self>>(methods: &mut M) {
             methods.add_method("magnitude", |_, vec, ()| {
                 let mag_squared = vec.0 * vec.0 + vec.1 * vec.1;
                 Ok(mag_squared.sqrt())
@@ -156,26 +177,21 @@ fn main() -> Result<()> {
     let vec2_constructor = lua.create_function(|_, (x, y): (f32, f32)| Ok(Vec2(x, y)))?;
     globals.set("vec2", vec2_constructor)?;
 
-    assert!(
-        (lua.load("(vec2(1, 2) + vec2(2, 2)):magnitude()")
-            .eval::<f32>()?
-            - 5.0)
-            .abs()
-            < f32::EPSILON
-    );
+    assert!((lua.load("(vec2(1, 2) + vec2(2, 2)):magnitude()").eval::<f32>()? - 5.0).abs() < f32::EPSILON);
 
-    // Normally, Rust types passed to `Lua` must be `Send`, because `Lua` itself is `Send`, and
-    // must be `'static`, because there is no way to be sure of their lifetime inside the Lua
-    // state.  There is, however, a limited way to lift both of these requirements.  You can
-    // call `Lua::scope` to create userdata and callbacks types that only live for as long
-    // as the call to scope, but do not have to be `Send` OR `'static`.
+    // Normally, Rust types passed to `Lua` must be `'static`, because there is no way to be
+    // sure of their lifetime inside the Lua state. There is, however, a limited way to lift this
+    // requirement. You can call `Lua::scope` to create userdata and callbacks types that only live
+    // for as long as the call to scope, but do not have to be `'static` (and `Send`).
 
+    // TODO: Re-enable this
+    /*
     {
         let mut rust_val = 0;
 
         lua.scope(|scope| {
             // We create a 'sketchy' Lua callback that holds a mutable reference to the variable
-            // `rust_val`.  Outside of a `Lua::scope` call, this would not be allowed
+            // `rust_val`. Outside of a `Lua::scope` call, this would not be allowed
             // because it could be unsafe.
 
             lua.globals().set(
@@ -191,10 +207,11 @@ fn main() -> Result<()> {
 
         assert_eq!(rust_val, 42);
     }
+    */
 
-    // We were able to run our 'sketchy' function inside the scope just fine.  However, if we
+    // We were able to run our 'sketchy' function inside the scope just fine. However, if we
     // try to run our 'sketchy' function outside of the scope, the function we created will have
-    // been invalidated and we will generate an error.  If our function wasn't invalidated, we
+    // been invalidated and we will generate an error. If our function wasn't invalidated, we
     // might be able to improperly access the freed `rust_val` which would be unsafe.
     assert!(lua.load("sketchy()").exec().is_err());
 

examples/module/.cargo/config

@@ -0,0 +1,11 @@
+[target.x86_64-apple-darwin]
+rustflags = [
+  "-C", "link-arg=-undefined",
+  "-C", "link-arg=dynamic_lookup",
+]
+
+[target.aarch64-apple-darwin]
+rustflags = [
+  "-C", "link-arg=-undefined",
+  "-C", "link-arg=dynamic_lookup",
+]

examples/module/Cargo.toml

@@ -0,0 +1,20 @@
+[package]
+name = "rust_module"
+version = "0.0.0"
+authors = ["Aleksandr Orlenko <zxteam@pm.me>"]
+edition = "2021"
+
+[lib]
+crate-type = ["cdylib"]
+
+[workspace]
+
+[features]
+lua54 = ["mlua/lua54"]
+lua53 = ["mlua/lua53"]
+lua52 = ["mlua/lua52"]
+lua51 = ["mlua/lua51"]
+luajit = ["mlua/luajit"]
+
+[dependencies]
+mlua = { path = "../..", features = ["module"] }

examples/module/src/lib.rs

@@ -0,0 +1,17 @@
+use mlua::prelude::*;
+
+fn sum(_: &Lua, (a, b): (i64, i64)) -> LuaResult<i64> {
+    Ok(a + b)
+}
+
+fn used_memory(lua: &Lua, _: ()) -> LuaResult<usize> {
+    Ok(lua.used_memory())
+}
+
+#[mlua::lua_module]
+fn rust_module(lua: &Lua) -> LuaResult<LuaTable> {
+    let exports = lua.create_table()?;
+    exports.set("sum", lua.create_function(sum)?)?;
+    exports.set("used_memory", lua.create_function(used_memory)?)?;
+    Ok(exports)
+}

examples/repl.rs

@@ -1,11 +1,11 @@
 //! This example shows a simple read-evaluate-print-loop (REPL).
 
 use mlua::{Error, Lua, MultiValue};
-use rustyline::Editor;
+use rustyline::DefaultEditor;
 
 fn main() {
     let lua = Lua::new();
-    let mut editor = Editor::<()>::new();
+    let mut editor = DefaultEditor::new().expect("Failed to create editor");
 
     loop {
         let mut prompt = "> ";
@@ -19,15 +19,17 @@ fn main() {
 
             match lua.load(&line).eval::<MultiValue>() {
                 Ok(values) => {
-                    editor.add_history_entry(line);
-                    println!(
-                        "{}",
-                        values
-                            .iter()
-                            .map(|value| format!("{:?}", value))
-                            .collect::<Vec<_>>()
-                            .join("\t")
-                    );
+                    editor.add_history_entry(line).unwrap();
+                    if values.len() > 0 {
+                        println!(
+                            "{}",
+                            values
+                                .iter()
+                                .map(|value| format!("{:#?}", value))
+                                .collect::<Vec<_>>()
+                                .join("\t")
+                        );
+                    }
                     break;
                 }
                 Err(Error::SyntaxError {

examples/serde.rs

@@ -0,0 +1,71 @@
+use mlua::{Error, Lua, LuaSerdeExt, Result, UserData, Value};
+use serde::{Deserialize, Serialize};
+
+#[derive(Serialize, Deserialize)]
+enum Transmission {
+    Manual,
+    Automatic,
+}
+
+#[derive(Serialize, Deserialize)]
+struct Engine {
+    v: u32,
+    kw: u32,
+}
+
+#[derive(Serialize, Deserialize)]
+struct Car {
+    active: bool,
+    model: String,
+    transmission: Transmission,
+    engine: Engine,
+}
+
+impl UserData for Car {}
+
+fn main() -> Result<()> {
+    let lua = Lua::new();
+    let globals = lua.globals();
+
+    // Create Car struct from a Lua table
+    let car: Car = lua.from_value(
+        lua.load(
+            r#"
+        {active = true, model = "Volkswagen Golf", transmission = "Automatic", engine = {v = 1499, kw = 90}}
+    "#,
+        )
+        .eval()?,
+    )?;
+
+    // Set it as (serializable) userdata
+    globals.set("null", lua.null())?;
+    globals.set("array_mt", lua.array_metatable())?;
+    globals.set("car", lua.create_ser_userdata(car)?)?;
+
+    // Create a Lua table with multiple data types
+    let val: Value = lua
+        .load(r#"{driver = "Boris", car = car, price = null, points = setmetatable({}, array_mt)}"#)
+        .eval()?;
+
+    // Serialize the table above to JSON
+    let json_str = serde_json::to_string(&val).map_err(Error::external)?;
+    println!("{}", json_str);
+
+    // Create Lua Value from JSON (or any serializable type)
+    let json = serde_json::json!({
+        "key": "value",
+        "null": null,
+        "array": [],
+    });
+    globals.set("json_value", lua.to_value(&json)?)?;
+    lua.load(
+        r#"
+        assert(json_value["key"] == "value")
+        assert(json_value["null"] == null)
+        assert(#(json_value["array"]) == 0)
+    "#,
+    )
+    .exec()?;
+
+    Ok(())
+}

examples/userdata.rs

@@ -0,0 +1,45 @@
+use mlua::{chunk, Lua, MetaMethod, Result, UserData};
+
+#[derive(Default)]
+struct Rectangle {
+    length: u32,
+    width: u32,
+}
+
+impl UserData for Rectangle {
+    fn add_fields<F: mlua::UserDataFields<Self>>(fields: &mut F) {
+        fields.add_field_method_get("length", |_, this| Ok(this.length));
+        fields.add_field_method_set("length", |_, this, val| {
+            this.length = val;
+            Ok(())
+        });
+        fields.add_field_method_get("width", |_, this| Ok(this.width));
+        fields.add_field_method_set("width", |_, this, val| {
+            this.width = val;
+            Ok(())
+        });
+    }
+
+    fn add_methods<M: mlua::UserDataMethods<Self>>(methods: &mut M) {
+        methods.add_method("area", |_, this, ()| Ok(this.length * this.width));
+        methods.add_method("diagonal", |_, this, ()| {
+            Ok((this.length.pow(2) as f64 + this.width.pow(2) as f64).sqrt())
+        });
+
+        // Constructor
+        methods.add_meta_function(MetaMethod::Call, |_, ()| Ok(Rectangle::default()));
+    }
+}
+
+fn main() -> Result<()> {
+    let lua = Lua::new();
+    let rectangle = Rectangle::default();
+    lua.load(chunk! {
+        local rect = $rectangle()
+        rect.width = 10
+        rect.length = 5
+        assert(rect:area() == 50)
+        assert(rect:diagonal() - 11.1803 < 0.0001)
+    })
+    .exec()
+}

mlua-sys/Cargo.toml

@@ -0,0 +1,47 @@
+[package]
+name = "mlua-sys"
+version = "0.8.3"
+authors = ["Aleksandr Orlenko <zxteam@pm.me>"]
+rust-version = "1.71"
+edition = "2021"
+repository = "https://github.com/mlua-rs/mlua"
+documentation = "https://docs.rs/mlua-sys"
+readme = "README.md"
+categories = ["external-ffi-bindings"]
+license = "MIT"
+links = "lua"
+build = "build/main.rs"
+description = """
+Low level (FFI) bindings to Lua 5.4/5.3/5.2/5.1 (including LuaJIT) and Luau
+"""
+
+[package.metadata.docs.rs]
+features = ["lua54", "vendored"]
+rustdoc-args = ["--cfg", "docsrs"]
+
+[features]
+lua54 = []
+lua53 = []
+lua52 = []
+lua51 = []
+luajit = []
+luajit52 = ["luajit"]
+luau = ["luau0-src"]
+luau-codegen = ["luau"]
+luau-vector4 = ["luau"]
+vendored = ["lua-src", "luajit-src"]
+external = []
+module = []
+
+[dependencies]
+
+[build-dependencies]
+cc = "1.0"
+cfg-if = "1.0"
+pkg-config = "0.3.17"
+lua-src = { version = ">= 548.1.0, < 548.2.0", optional = true }
+luajit-src = { version = ">= 210.6.0, < 210.7.0", optional = true }
+luau0-src = { version = "0.15.6", optional = true }
+
+[lints.rust]
+unexpected_cfgs = { level = "allow", check-cfg = ['cfg(raw_dylib)'] }

mlua-sys/README.md

@@ -0,0 +1,8 @@
+# mlua-sys
+
+Low level (FFI) bindings to Lua 5.4/5.3/5.2/5.1 (including LuaJIT) and [Luau].
+
+Intended to be consumed by the [mlua] crate.
+
+[Luau]: https://github.com/luau-lang/luau
+[mlua]: https://crates.io/crates/mlua

mlua-sys/build/find_normal.rs

@@ -0,0 +1,68 @@
+#![allow(dead_code)]
+
+use std::env;
+use std::ops::Bound;
+
+pub fn probe_lua() {
+    let target_arch = env::var("CARGO_CFG_TARGET_ARCH").unwrap();
+
+    if target_arch == "wasm32" && cfg!(not(feature = "vendored")) {
+        panic!("Please enable `vendored` feature to build for wasm32");
+    }
+
+    let lib_dir = env::var("LUA_LIB").unwrap_or_default();
+    let lua_lib = env::var("LUA_LIB_NAME").unwrap_or_default();
+
+    println!("cargo:rerun-if-env-changed=LUA_LIB");
+    println!("cargo:rerun-if-env-changed=LUA_LIB_NAME");
+    println!("cargo:rerun-if-env-changed=LUA_LINK");
+
+    if !lua_lib.is_empty() {
+        if !lib_dir.is_empty() {
+            println!("cargo:rustc-link-search=native={lib_dir}");
+        }
+        let mut link_lib = "";
+        if env::var("LUA_LINK").as_deref() == Ok("static") {
+            link_lib = "static=";
+        };
+        println!("cargo:rustc-link-lib={link_lib}{lua_lib}");
+        return;
+    }
+
+    // Find using `pkg-config`
+
+    #[cfg(feature = "lua54")]
+    let (incl_bound, excl_bound, alt_probe, ver) =
+        ("5.4", "5.5", ["lua5.4", "lua-5.4", "lua54"], "5.4");
+    #[cfg(feature = "lua53")]
+    let (incl_bound, excl_bound, alt_probe, ver) =
+        ("5.3", "5.4", ["lua5.3", "lua-5.3", "lua53"], "5.3");
+    #[cfg(feature = "lua52")]
+    let (incl_bound, excl_bound, alt_probe, ver) =
+        ("5.2", "5.3", ["lua5.2", "lua-5.2", "lua52"], "5.2");
+    #[cfg(feature = "lua51")]
+    let (incl_bound, excl_bound, alt_probe, ver) =
+        ("5.1", "5.2", ["lua5.1", "lua-5.1", "lua51"], "5.1");
+    #[cfg(feature = "luajit")]
+    let (incl_bound, excl_bound, alt_probe, ver) = ("2.0.4", "2.2", [], "JIT");
+
+    #[rustfmt::skip]
+    let mut lua = pkg_config::Config::new()
+        .range_version((Bound::Included(incl_bound), Bound::Excluded(excl_bound)))
+        .cargo_metadata(true)
+        .probe(if cfg!(feature = "luajit") { "luajit" } else { "lua" });
+
+    if lua.is_err() {
+        for pkg in alt_probe {
+            lua = pkg_config::Config::new()
+                .cargo_metadata(true)
+                .probe(pkg);
+
+            if lua.is_ok() {
+                break;
+            }
+        }
+    }
+
+    lua.unwrap_or_else(|err| panic!("cannot find Lua{ver} using `pkg-config`: {err}"));
+}

mlua-sys/build/find_vendored.rs

@@ -0,0 +1,29 @@
+#![allow(dead_code)]
+
+pub fn probe_lua() {
+    #[cfg(feature = "lua54")]
+    let artifacts = lua_src::Build::new().build(lua_src::Lua54);
+
+    #[cfg(feature = "lua53")]
+    let artifacts = lua_src::Build::new().build(lua_src::Lua53);
+
+    #[cfg(feature = "lua52")]
+    let artifacts = lua_src::Build::new().build(lua_src::Lua52);
+
+    #[cfg(feature = "lua51")]
+    let artifacts = lua_src::Build::new().build(lua_src::Lua51);
+
+    #[cfg(feature = "luajit")]
+    let artifacts = luajit_src::Build::new()
+        .lua52compat(cfg!(feature = "luajit52"))
+        .build();
+
+    #[cfg(feature = "luau")]
+    let artifacts = luau0_src::Build::new()
+        .enable_codegen(cfg!(feature = "luau-codegen"))
+        .set_max_cstack_size(1000000)
+        .set_vector_size(if cfg!(feature = "luau-vector4") { 4 } else { 3 })
+        .build();
+
+    artifacts.print_cargo_metadata();
+}

mlua-sys/build/main.rs

@@ -0,0 +1,19 @@
+cfg_if::cfg_if! {
+    if #[cfg(all(feature = "lua54", not(any(feature = "lua53", feature = "lua52", feature = "lua51", feature = "luajit", feature = "luau"))))] {
+        include!("main_inner.rs");
+    } else if #[cfg(all(feature = "lua53", not(any(feature = "lua54", feature = "lua52", feature = "lua51", feature = "luajit", feature = "luau"))))] {
+        include!("main_inner.rs");
+    } else if #[cfg(all(feature = "lua52", not(any(feature = "lua54", feature = "lua53", feature = "lua51", feature = "luajit", feature = "luau"))))] {
+        include!("main_inner.rs");
+    } else if #[cfg(all(feature = "lua51", not(any(feature = "lua54", feature = "lua53", feature = "lua52", feature = "luajit", feature = "luau"))))] {
+        include!("main_inner.rs");
+    } else if #[cfg(all(feature = "luajit", not(any(feature = "lua54", feature = "lua53", feature = "lua52", feature = "lua51", feature = "luau"))))] {
+        include!("main_inner.rs");
+    } else if #[cfg(all(feature = "luau", not(any(feature = "lua54", feature = "lua53", feature = "lua52", feature = "lua51", feature = "luajit"))))] {
+        include!("main_inner.rs");
+    } else {
+        fn main() {
+            compile_error!("You can enable only one of the features: lua54, lua53, lua52, lua51, luajit, luajit52, luau");
+        }
+    }
+}

mlua-sys/build/main_inner.rs

@@ -0,0 +1,42 @@
+use std::env;
+
+cfg_if::cfg_if! {
+    if #[cfg(any(feature = "luau", feature = "vendored"))] {
+        #[path = "find_vendored.rs"]
+        mod find;
+    } else {
+        #[path = "find_normal.rs"]
+        mod find;
+    }
+}
+
+fn main() {
+    #[cfg(all(feature = "luau", feature = "module", windows))]
+    compile_error!("Luau does not support `module` mode on Windows");
+
+    #[cfg(any(
+        all(feature = "vendored", any(feature = "external", feature = "module")),
+        all(feature = "external", any(feature = "vendored", feature = "module")),
+        all(feature = "module", any(feature = "vendored", feature = "external"))
+    ))]
+    compile_error!("`vendored`, `external` and `module` features are mutually exclusive");
+
+    println!("cargo:rerun-if-changed=build");
+
+    // Check if compilation and linking is handled by external crate
+    if cfg!(not(feature = "external")) {
+        let target_os = env::var("CARGO_CFG_TARGET_OS").unwrap();
+        if target_os == "windows" && cfg!(feature = "module") {
+            if !std::env::var("LUA_LIB_NAME").unwrap_or_default().is_empty() {
+                // Don't use raw-dylib linking
+                find::probe_lua();
+                return;
+            }
+
+            println!("cargo:rustc-cfg=raw_dylib");
+        }
+
+        #[cfg(not(feature = "module"))]
+        find::probe_lua();
+    }
+}

mlua-sys/src/lib.rs

@@ -0,0 +1,106 @@
+//! Low level bindings to Lua 5.4/5.3/5.2/5.1 (including LuaJIT) and Luau.
+
+#![allow(non_camel_case_types, non_snake_case)]
+#![allow(clippy::missing_safety_doc)]
+#![allow(unsafe_op_in_unsafe_fn)]
+#![doc(test(attr(deny(warnings))))]
+#![cfg_attr(docsrs, feature(doc_cfg))]
+
+use std::os::raw::c_int;
+
+#[cfg(any(feature = "lua54", doc))]
+pub use lua54::*;
+
+#[cfg(any(feature = "lua53", doc))]
+pub use lua53::*;
+
+#[cfg(any(feature = "lua52", doc))]
+pub use lua52::*;
+
+#[cfg(any(feature = "lua51", feature = "luajit", doc))]
+pub use lua51::*;
+
+#[cfg(any(feature = "luau", doc))]
+pub use luau::*;
+
+#[cfg(any(feature = "lua54", feature = "lua53", feature = "lua52"))]
+#[doc(hidden)]
+pub const LUA_MAX_UPVALUES: c_int = 255;
+
+#[cfg(any(feature = "lua51", feature = "luajit"))]
+#[doc(hidden)]
+pub const LUA_MAX_UPVALUES: c_int = 60;
+
+#[cfg(feature = "luau")]
+#[doc(hidden)]
+pub const LUA_MAX_UPVALUES: c_int = 200;
+
+// I believe `luaL_traceback` < 5.4 requires this much free stack to not error.
+// 5.4 uses `luaL_Buffer`
+#[doc(hidden)]
+pub const LUA_TRACEBACK_STACK: c_int = 11;
+
+// Copied from https://github.com/rust-lang/rust/blob/master/library/std/src/sys/pal/common/alloc.rs
+// The minimum alignment guaranteed by the architecture. This value is used to
+// add fast paths for low alignment values.
+#[cfg(any(
+    target_arch = "x86",
+    target_arch = "arm",
+    target_arch = "m68k",
+    target_arch = "csky",
+    target_arch = "mips",
+    target_arch = "mips32r6",
+    target_arch = "powerpc",
+    target_arch = "powerpc64",
+    target_arch = "sparc",
+    target_arch = "wasm32",
+    target_arch = "hexagon",
+    all(target_arch = "riscv32", not(any(target_os = "espidf", target_os = "zkvm"))),
+    all(target_arch = "xtensa", not(target_os = "espidf")),
+))]
+#[doc(hidden)]
+pub const SYS_MIN_ALIGN: usize = 8;
+#[cfg(any(
+    target_arch = "x86_64",
+    target_arch = "aarch64",
+    target_arch = "arm64ec",
+    target_arch = "loongarch64",
+    target_arch = "mips64",
+    target_arch = "mips64r6",
+    target_arch = "s390x",
+    target_arch = "sparc64",
+    target_arch = "riscv64",
+    target_arch = "wasm64",
+))]
+#[doc(hidden)]
+pub const SYS_MIN_ALIGN: usize = 16;
+// The allocator on the esp-idf and zkvm platforms guarantee 4 byte alignment.
+#[cfg(any(
+    all(target_arch = "riscv32", any(target_os = "espidf", target_os = "zkvm")),
+    all(target_arch = "xtensa", target_os = "espidf"),
+))]
+#[doc(hidden)]
+pub const SYS_MIN_ALIGN: usize = 4;
+
+#[macro_use]
+mod macros;
+
+#[cfg(any(feature = "lua54", doc))]
+#[cfg_attr(docsrs, doc(cfg(feature = "lua54")))]
+pub mod lua54;
+
+#[cfg(any(feature = "lua53", doc))]
+#[cfg_attr(docsrs, doc(cfg(feature = "lua53")))]
+pub mod lua53;
+
+#[cfg(any(feature = "lua52", doc))]
+#[cfg_attr(docsrs, doc(cfg(feature = "lua52")))]
+pub mod lua52;
+
+#[cfg(any(feature = "lua51", feature = "luajit", doc))]
+#[cfg_attr(docsrs, doc(cfg(any(feature = "lua51", feature = "luajit"))))]
+pub mod lua51;
+
+#[cfg(any(feature = "luau", doc))]
+#[cfg_attr(docsrs, doc(cfg(feature = "luau")))]
+pub mod luau;

mlua-sys/src/lua51/compat.rs

@@ -0,0 +1,577 @@
+//! MLua compatibility layer for Lua 5.1/JIT
+//!
+//! Based on github.com/keplerproject/lua-compat-5.3
+
+use std::os::raw::{c_char, c_int, c_void};
+use std::{mem, ptr};
+
+use super::lauxlib::*;
+use super::lua::*;
+
+#[inline(always)]
+unsafe fn compat53_reverse(L: *mut lua_State, mut a: c_int, mut b: c_int) {
+    while a < b {
+        lua_pushvalue(L, a);
+        lua_pushvalue(L, b);
+        lua_replace(L, a);
+        lua_replace(L, b);
+        a += 1;
+        b -= 1;
+    }
+}
+
+const COMPAT53_LEVELS1: c_int = 12; // size of the first part of the stack
+const COMPAT53_LEVELS2: c_int = 10; // size of the second part of the stack
+
+unsafe fn compat53_countlevels(L: *mut lua_State) -> c_int {
+    let mut ar: lua_Debug = mem::zeroed();
+    let (mut li, mut le) = (1, 1);
+    // find an upper bound
+    while lua_getstack(L, le, &mut ar) != 0 {
+        li = le;
+        le *= 2;
+    }
+    // do a binary search
+    while li < le {
+        let m = (li + le) / 2;
+        if lua_getstack(L, m, &mut ar) != 0 {
+            li = m + 1
+        } else {
+            le = m;
+        }
+    }
+    le - 1
+}
+
+unsafe fn compat53_checkmode(
+    L: *mut lua_State,
+    mode: *const c_char,
+    modename: *const c_char,
+    err: c_int,
+) -> c_int {
+    unsafe fn strchr(s: *const c_char, c: c_char) -> *const c_char {
+        let mut st = s;
+        while *st != 0 && *st != c {
+            st = st.offset(1);
+        }
+        if *st == c {
+            st
+        } else {
+            ptr::null()
+        }
+    }
+
+    if !mode.is_null() && strchr(mode, *modename).is_null() {
+        lua_pushfstring(
+            L,
+            cstr!("attempt to load a %s chunk (mode is '%s')"),
+            modename,
+            mode,
+        );
+        return err;
+    }
+    LUA_OK
+}
+
+unsafe fn compat53_findfield(L: *mut lua_State, objidx: c_int, level: c_int) -> c_int {
+    if level == 0 || lua_istable(L, -1) == 0 {
+        return 0; // not found
+    }
+
+    lua_pushnil(L); // start 'next' loop
+    while lua_next(L, -2) != 0 {
+        // for each pair in table
+        if lua_type(L, -2) == LUA_TSTRING {
+            // ignore non-string keys
+            if lua_rawequal(L, objidx, -1) != 0 {
+                // found object?
+                lua_pop(L, 1); // remove value (but keep name)
+                return 1;
+            } else if compat53_findfield(L, objidx, level - 1) != 0 {
+                // try recursively
+                lua_remove(L, -2); // remove table (but keep name)
+                lua_pushliteral(L, c".");
+                lua_insert(L, -2); // place '.' between the two names
+                lua_concat(L, 3);
+                return 1;
+            }
+        }
+        lua_pop(L, 1); // remove value
+    }
+    0 // not found
+}
+
+unsafe fn compat53_pushglobalfuncname(L: *mut lua_State, ar: *mut lua_Debug) -> c_int {
+    let top = lua_gettop(L);
+    lua_getinfo(L, cstr!("f"), ar); // push function
+    lua_pushvalue(L, LUA_GLOBALSINDEX);
+    if compat53_findfield(L, top + 1, 2) != 0 {
+        lua_copy(L, -1, top + 1); // move name to proper place
+        lua_pop(L, 2); // remove pushed values
+        1
+    } else {
+        lua_settop(L, top); // remove function and global table
+        0
+    }
+}
+
+unsafe fn compat53_pushfuncname(L: *mut lua_State, ar: *mut lua_Debug) {
+    if *(*ar).namewhat != b'\0' as c_char {
+        // is there a name?
+        lua_pushfstring(L, cstr!("function '%s'"), (*ar).name);
+    } else if *(*ar).what == b'm' as c_char {
+        // main?
+        lua_pushliteral(L, c"main chunk");
+    } else if *(*ar).what == b'C' as c_char {
+        if compat53_pushglobalfuncname(L, ar) != 0 {
+            lua_pushfstring(L, cstr!("function '%s'"), lua_tostring(L, -1));
+            lua_remove(L, -2); // remove name
+        } else {
+            lua_pushliteral(L, c"?");
+        }
+    } else {
+        lua_pushfstring(
+            L,
+            cstr!("function <%s:%d>"),
+            (*ar).short_src.as_ptr(),
+            (*ar).linedefined,
+        );
+    }
+}
+
+//
+// lua ported functions
+//
+
+#[inline(always)]
+pub unsafe fn lua_absindex(L: *mut lua_State, mut idx: c_int) -> c_int {
+    if idx < 0 && idx > LUA_REGISTRYINDEX {
+        idx += lua_gettop(L) + 1;
+    }
+    idx
+}
+
+pub unsafe fn lua_rotate(L: *mut lua_State, mut idx: c_int, mut n: c_int) {
+    idx = lua_absindex(L, idx);
+    if n > 0 {
+        // Faster version
+        for _ in 0..n {
+            lua_insert(L, idx);
+        }
+        return;
+    }
+    let n_elems = lua_gettop(L) - idx + 1;
+    if n < 0 {
+        n += n_elems;
+    }
+    if n > 0 && n < n_elems {
+        luaL_checkstack(L, 2, cstr!("not enough stack slots available"));
+        n = n_elems - n;
+        compat53_reverse(L, idx, idx + n - 1);
+        compat53_reverse(L, idx + n, idx + n_elems - 1);
+        compat53_reverse(L, idx, idx + n_elems - 1);
+    }
+}
+
+#[inline(always)]
+pub unsafe fn lua_copy(L: *mut lua_State, fromidx: c_int, toidx: c_int) {
+    let abs_to = lua_absindex(L, toidx);
+    luaL_checkstack(L, 1, cstr!("not enough stack slots available"));
+    lua_pushvalue(L, fromidx);
+    lua_replace(L, abs_to);
+}
+
+#[inline(always)]
+pub unsafe fn lua_isinteger(L: *mut lua_State, idx: c_int) -> c_int {
+    if lua_type(L, idx) == LUA_TNUMBER {
+        let n = lua_tonumber(L, idx);
+        let i = lua_tointeger(L, idx);
+        // Lua 5.3+ returns "false" for `-0.0`
+        if n.to_bits() == (i as lua_Number).to_bits() {
+            return 1;
+        }
+    }
+    0
+}
+
+#[inline(always)]
+pub unsafe fn lua_tointeger(L: *mut lua_State, i: c_int) -> lua_Integer {
+    lua_tointegerx(L, i, ptr::null_mut())
+}
+
+#[inline(always)]
+pub unsafe fn lua_tonumberx(L: *mut lua_State, i: c_int, isnum: *mut c_int) -> lua_Number {
+    let n = lua_tonumber(L, i);
+    if !isnum.is_null() {
+        *isnum = (n != 0.0 || lua_isnumber(L, i) != 0) as c_int;
+    }
+    n
+}
+
+#[inline(always)]
+pub unsafe fn lua_tointegerx(L: *mut lua_State, i: c_int, isnum: *mut c_int) -> lua_Integer {
+    let mut ok = 0;
+    let n = lua_tonumberx(L, i, &mut ok);
+    let n_int = n as lua_Integer;
+    if ok != 0 && (n - n_int as lua_Number).abs() < lua_Number::EPSILON {
+        if !isnum.is_null() {
+            *isnum = 1;
+        }
+        return n_int;
+    }
+    if !isnum.is_null() {
+        *isnum = 0;
+    }
+    0
+}
+
+#[inline(always)]
+pub unsafe fn lua_rawlen(L: *mut lua_State, idx: c_int) -> usize {
+    lua_objlen(L, idx)
+}
+
+#[inline(always)]
+pub unsafe fn lua_pushlstring(L: *mut lua_State, s: *const c_char, l: usize) -> *const c_char {
+    if l == 0 {
+        lua_pushlstring_(L, cstr!(""), 0);
+    } else {
+        lua_pushlstring_(L, s, l);
+    }
+    lua_tostring(L, -1)
+}
+
+#[inline(always)]
+pub unsafe fn lua_pushstring(L: *mut lua_State, s: *const c_char) -> *const c_char {
+    lua_pushstring_(L, s);
+    lua_tostring(L, -1)
+}
+
+#[inline(always)]
+pub unsafe fn lua_getglobal(L: *mut lua_State, var: *const c_char) -> c_int {
+    lua_getglobal_(L, var);
+    lua_type(L, -1)
+}
+
+#[inline(always)]
+pub unsafe fn lua_gettable(L: *mut lua_State, idx: c_int) -> c_int {
+    lua_gettable_(L, idx);
+    lua_type(L, -1)
+}
+
+#[inline(always)]
+pub unsafe fn lua_getfield(L: *mut lua_State, idx: c_int, k: *const c_char) -> c_int {
+    lua_getfield_(L, idx, k);
+    lua_type(L, -1)
+}
+
+#[inline(always)]
+pub unsafe fn lua_geti(L: *mut lua_State, mut idx: c_int, n: lua_Integer) -> c_int {
+    idx = lua_absindex(L, idx);
+    lua_pushinteger(L, n);
+    lua_gettable(L, idx)
+}
+
+#[inline(always)]
+pub unsafe fn lua_rawget(L: *mut lua_State, idx: c_int) -> c_int {
+    lua_rawget_(L, idx);
+    lua_type(L, -1)
+}
+
+#[inline(always)]
+pub unsafe fn lua_rawgeti(L: *mut lua_State, idx: c_int, n: lua_Integer) -> c_int {
+    let n = n.try_into().expect("cannot convert index to lua_Integer");
+    lua_rawgeti_(L, idx, n);
+    lua_type(L, -1)
+}
+
+#[inline(always)]
+pub unsafe fn lua_rawgetp(L: *mut lua_State, idx: c_int, p: *const c_void) -> c_int {
+    let abs_i = lua_absindex(L, idx);
+    lua_pushlightuserdata(L, p as *mut c_void);
+    lua_rawget(L, abs_i)
+}
+
+#[inline(always)]
+pub unsafe fn lua_getuservalue(L: *mut lua_State, idx: c_int) -> c_int {
+    lua_getfenv(L, idx);
+    lua_type(L, -1)
+}
+
+#[inline(always)]
+pub unsafe fn lua_seti(L: *mut lua_State, mut idx: c_int, n: lua_Integer) {
+    luaL_checkstack(L, 1, cstr!("not enough stack slots available"));
+    idx = lua_absindex(L, idx);
+    lua_pushinteger(L, n);
+    lua_insert(L, -2);
+    lua_settable(L, idx);
+}
+
+#[inline(always)]
+pub unsafe fn lua_rawseti(L: *mut lua_State, idx: c_int, n: lua_Integer) {
+    let n = n.try_into().expect("cannot convert index from lua_Integer");
+    lua_rawseti_(L, idx, n)
+}
+
+#[inline(always)]
+pub unsafe fn lua_rawsetp(L: *mut lua_State, idx: c_int, p: *const c_void) {
+    let abs_i = lua_absindex(L, idx);
+    luaL_checkstack(L, 1, cstr!("not enough stack slots available"));
+    lua_pushlightuserdata(L, p as *mut c_void);
+    lua_insert(L, -2);
+    lua_rawset(L, abs_i);
+}
+
+#[inline(always)]
+pub unsafe fn lua_setuservalue(L: *mut lua_State, idx: c_int) {
+    luaL_checktype(L, -1, LUA_TTABLE);
+    lua_setfenv(L, idx);
+}
+
+#[inline(always)]
+pub unsafe fn lua_dump(L: *mut lua_State, writer: lua_Writer, data: *mut c_void, _strip: c_int) -> c_int {
+    lua_dump_(L, writer, data)
+}
+
+#[inline(always)]
+pub unsafe fn lua_len(L: *mut lua_State, idx: c_int) {
+    match lua_type(L, idx) {
+        LUA_TSTRING => {
+            lua_pushnumber(L, lua_objlen(L, idx) as lua_Number);
+        }
+        LUA_TTABLE => {
+            if luaL_callmeta(L, idx, cstr!("__len")) == 0 {
+                lua_pushnumber(L, lua_objlen(L, idx) as lua_Number);
+            }
+        }
+        LUA_TUSERDATA if luaL_callmeta(L, idx, cstr!("__len")) != 0 => {}
+        _ => {
+            luaL_error(
+                L,
+                cstr!("attempt to get length of a %s value"),
+                lua_typename(L, lua_type(L, idx)),
+            );
+        }
+    }
+}
+
+#[inline(always)]
+pub unsafe fn lua_pushglobaltable(L: *mut lua_State) {
+    lua_pushvalue(L, LUA_GLOBALSINDEX);
+}
+
+#[inline(always)]
+pub unsafe fn lua_resume(L: *mut lua_State, _from: *mut lua_State, narg: c_int, nres: *mut c_int) -> c_int {
+    let ret = lua_resume_(L, narg);
+    if (ret == LUA_OK || ret == LUA_YIELD) && !(nres.is_null()) {
+        *nres = lua_gettop(L);
+    }
+    ret
+}
+
+//
+// lauxlib ported functions
+//
+
+#[inline(always)]
+pub unsafe fn luaL_checkstack(L: *mut lua_State, sz: c_int, msg: *const c_char) {
+    if lua_checkstack(L, sz + LUA_MINSTACK) == 0 {
+        if !msg.is_null() {
+            luaL_error(L, cstr!("stack overflow (%s)"), msg);
+        } else {
+            lua_pushliteral(L, c"stack overflow");
+            lua_error(L);
+        }
+    }
+}
+
+#[inline(always)]
+pub unsafe fn luaL_getmetafield(L: *mut lua_State, obj: c_int, e: *const c_char) -> c_int {
+    if luaL_getmetafield_(L, obj, e) != 0 {
+        lua_type(L, -1)
+    } else {
+        LUA_TNIL
+    }
+}
+
+#[inline(always)]
+pub unsafe fn luaL_newmetatable(L: *mut lua_State, tname: *const c_char) -> c_int {
+    if luaL_newmetatable_(L, tname) != 0 {
+        lua_pushstring_(L, tname);
+        lua_setfield(L, -2, cstr!("__name"));
+        1
+    } else {
+        0
+    }
+}
+
+pub unsafe fn luaL_loadbufferenv(
+    L: *mut lua_State,
+    data: *const c_char,
+    size: usize,
+    name: *const c_char,
+    mode: *const c_char,
+    mut env: c_int,
+) -> c_int {
+    if env != 0 {
+        env = lua_absindex(L, env);
+    }
+    let status = luaL_loadbufferx(L, data, size, name, mode);
+    if status == LUA_OK && env != 0 {
+        lua_pushvalue(L, env);
+        lua_setfenv(L, -2);
+    }
+    status
+}
+
+#[inline(always)]
+pub unsafe fn luaL_loadbufferx(
+    L: *mut lua_State,
+    buff: *const c_char,
+    sz: usize,
+    name: *const c_char,
+    mode: *const c_char,
+) -> c_int {
+    let status = if sz > 0 && *buff as u8 == LUA_SIGNATURE[0] {
+        compat53_checkmode(L, mode, cstr!("binary"), LUA_ERRSYNTAX)
+    } else {
+        compat53_checkmode(L, mode, cstr!("text"), LUA_ERRSYNTAX)
+    };
+    if status != LUA_OK {
+        return status;
+    }
+    luaL_loadbuffer(L, buff, sz, name)
+}
+
+#[inline(always)]
+pub unsafe fn luaL_len(L: *mut lua_State, idx: c_int) -> lua_Integer {
+    let mut isnum = 0;
+    luaL_checkstack(L, 1, cstr!("not enough stack slots available"));
+    lua_len(L, idx);
+    let res = lua_tointegerx(L, -1, &mut isnum);
+    lua_pop(L, 1);
+    if isnum == 0 {
+        luaL_error(L, cstr!("object length is not an integer"));
+    }
+    res
+}
+
+pub unsafe fn luaL_traceback(L: *mut lua_State, L1: *mut lua_State, msg: *const c_char, mut level: c_int) {
+    let mut ar: lua_Debug = mem::zeroed();
+    let top = lua_gettop(L);
+    let numlevels = compat53_countlevels(L1);
+    let mark = if numlevels > COMPAT53_LEVELS1 + COMPAT53_LEVELS2 {
+        COMPAT53_LEVELS1
+    } else {
+        0
+    };
+
+    if !msg.is_null() {
+        lua_pushfstring(L, cstr!("%s\n"), msg);
+    }
+    lua_pushliteral(L, c"stack traceback:");
+    while lua_getstack(L1, level, &mut ar) != 0 {
+        level += 1;
+        if level == mark {
+            // too many levels?
+            lua_pushliteral(L, c"\n\t..."); // add a '...'
+            level = numlevels - COMPAT53_LEVELS2; // and skip to last ones
+        } else {
+            lua_getinfo(L1, cstr!("Slnt"), &mut ar);
+            lua_pushfstring(L, cstr!("\n\t%s:"), ar.short_src.as_ptr());
+            if ar.currentline > 0 {
+                lua_pushfstring(L, cstr!("%d:"), ar.currentline);
+            }
+            lua_pushliteral(L, c" in ");
+            compat53_pushfuncname(L, &mut ar);
+            lua_concat(L, lua_gettop(L) - top);
+        }
+    }
+    lua_concat(L, lua_gettop(L) - top);
+}
+
+pub unsafe fn luaL_tolstring(L: *mut lua_State, mut idx: c_int, len: *mut usize) -> *const c_char {
+    idx = lua_absindex(L, idx);
+    if luaL_callmeta(L, idx, cstr!("__tostring")) == 0 {
+        match lua_type(L, idx) {
+            LUA_TNIL => {
+                lua_pushliteral(L, c"nil");
+            }
+            LUA_TSTRING | LUA_TNUMBER => {
+                lua_pushvalue(L, idx);
+            }
+            LUA_TBOOLEAN => {
+                if lua_toboolean(L, idx) == 0 {
+                    lua_pushliteral(L, c"false");
+                } else {
+                    lua_pushliteral(L, c"true");
+                }
+            }
+            t => {
+                let tt = luaL_getmetafield(L, idx, cstr!("__name"));
+                let name = if tt == LUA_TSTRING {
+                    lua_tostring(L, -1)
+                } else {
+                    lua_typename(L, t)
+                };
+                lua_pushfstring(L, cstr!("%s: %p"), name, lua_topointer(L, idx));
+                if tt != LUA_TNIL {
+                    lua_replace(L, -2); // remove '__name'
+                }
+            }
+        };
+    } else if lua_isstring(L, -1) == 0 {
+        luaL_error(L, cstr!("'__tostring' must return a string"));
+    }
+    lua_tolstring(L, -1, len)
+}
+
+#[inline(always)]
+pub unsafe fn luaL_setmetatable(L: *mut lua_State, tname: *const c_char) {
+    luaL_checkstack(L, 1, cstr!("not enough stack slots available"));
+    luaL_getmetatable(L, tname);
+    lua_setmetatable(L, -2);
+}
+
+pub unsafe fn luaL_getsubtable(L: *mut lua_State, idx: c_int, fname: *const c_char) -> c_int {
+    let abs_i = lua_absindex(L, idx);
+    luaL_checkstack(L, 3, cstr!("not enough stack slots available"));
+    lua_pushstring_(L, fname);
+    if lua_gettable(L, abs_i) == LUA_TTABLE {
+        return 1;
+    }
+    lua_pop(L, 1);
+    lua_newtable(L);
+    lua_pushstring_(L, fname);
+    lua_pushvalue(L, -2);
+    lua_settable(L, abs_i);
+    0
+}
+
+pub unsafe fn luaL_requiref(L: *mut lua_State, modname: *const c_char, openf: lua_CFunction, glb: c_int) {
+    luaL_checkstack(L, 3, cstr!("not enough stack slots available"));
+    luaL_getsubtable(L, LUA_REGISTRYINDEX, LUA_LOADED_TABLE);
+    if lua_getfield(L, -1, modname) == LUA_TNIL {
+        lua_pop(L, 1);
+        lua_pushcfunction(L, openf);
+        lua_pushstring(L, modname);
+        #[cfg(feature = "lua51")]
+        {
+            lua_call(L, 1, 1);
+            lua_pushvalue(L, -1);
+            lua_setfield(L, -3, modname);
+        }
+        #[cfg(feature = "luajit")]
+        {
+            lua_call(L, 1, 0);
+            lua_getfield(L, -1, modname);
+        }
+    }
+    if glb != 0 {
+        lua_pushvalue(L, -1);
+        lua_setglobal(L, modname);
+    } else {
+        lua_pushnil(L);
+        lua_setglobal(L, modname);
+    }
+    lua_replace(L, -2);
+}

mlua-sys/src/lua51/lauxlib.rs

@@ -0,0 +1,145 @@
+//! Contains definitions from `lauxlib.h`.
+
+use std::os::raw::{c_char, c_int, c_void};
+use std::ptr;
+
+use super::lua::{self, lua_CFunction, lua_Integer, lua_Number, lua_State};
+
+// Extra error code for 'luaL_load'
+pub const LUA_ERRFILE: c_int = lua::LUA_ERRERR + 1;
+
+// Key, in the registry, for table of loaded modules
+pub const LUA_LOADED_TABLE: *const c_char = cstr!("_LOADED");
+
+#[repr(C)]
+pub struct luaL_Reg {
+    pub name: *const c_char,
+    pub func: lua_CFunction,
+}
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua51", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    pub fn luaL_register(L: *mut lua_State, libname: *const c_char, l: *const luaL_Reg);
+    #[link_name = "luaL_getmetafield"]
+    pub fn luaL_getmetafield_(L: *mut lua_State, obj: c_int, e: *const c_char) -> c_int;
+    pub fn luaL_callmeta(L: *mut lua_State, obj: c_int, e: *const c_char) -> c_int;
+    pub fn luaL_typerror(L: *mut lua_State, narg: c_int, tname: *const c_char) -> c_int;
+    pub fn luaL_argerror(L: *mut lua_State, narg: c_int, extramsg: *const c_char) -> c_int;
+    pub fn luaL_checklstring(L: *mut lua_State, narg: c_int, l: *mut usize) -> *const c_char;
+    pub fn luaL_optlstring(
+        L: *mut lua_State,
+        narg: c_int,
+        def: *const c_char,
+        l: *mut usize,
+    ) -> *const c_char;
+    pub fn luaL_checknumber(L: *mut lua_State, narg: c_int) -> lua_Number;
+    pub fn luaL_optnumber(L: *mut lua_State, narg: c_int, def: lua_Number) -> lua_Number;
+    pub fn luaL_checkinteger(L: *mut lua_State, narg: c_int) -> lua_Integer;
+    pub fn luaL_optinteger(L: *mut lua_State, narg: c_int, def: lua_Integer) -> lua_Integer;
+    #[link_name = "luaL_checkstack"]
+    pub fn luaL_checkstack_(L: *mut lua_State, sz: c_int, msg: *const c_char);
+    pub fn luaL_checktype(L: *mut lua_State, narg: c_int, t: c_int);
+    pub fn luaL_checkany(L: *mut lua_State, narg: c_int);
+
+    #[link_name = "luaL_newmetatable"]
+    pub fn luaL_newmetatable_(L: *mut lua_State, tname: *const c_char) -> c_int;
+    pub fn luaL_checkudata(L: *mut lua_State, ud: c_int, tname: *const c_char) -> *mut c_void;
+
+    pub fn luaL_where(L: *mut lua_State, lvl: c_int);
+    pub fn luaL_error(L: *mut lua_State, fmt: *const c_char, ...) -> c_int;
+
+    pub fn luaL_checkoption(
+        L: *mut lua_State,
+        narg: c_int,
+        def: *const c_char,
+        lst: *const *const c_char,
+    ) -> c_int;
+}
+
+// Pre-defined references
+pub const LUA_NOREF: c_int = -2;
+pub const LUA_REFNIL: c_int = -1;
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua51", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    pub fn luaL_ref(L: *mut lua_State, t: c_int) -> c_int;
+    pub fn luaL_unref(L: *mut lua_State, t: c_int, r#ref: c_int);
+
+    pub fn luaL_loadfile(L: *mut lua_State, filename: *const c_char) -> c_int;
+    pub fn luaL_loadbuffer(L: *mut lua_State, buff: *const c_char, sz: usize, name: *const c_char) -> c_int;
+    pub fn luaL_loadstring(L: *mut lua_State, s: *const c_char) -> c_int;
+
+    pub fn luaL_newstate() -> *mut lua_State;
+
+    pub fn luaL_gsub(
+        L: *mut lua_State,
+        s: *const c_char,
+        p: *const c_char,
+        r: *const c_char,
+    ) -> *const c_char;
+
+    pub fn luaL_findtable(
+        L: *mut lua_State,
+        idx: c_int,
+        fname: *const c_char,
+        szhint: c_int,
+    ) -> *const c_char;
+}
+
+//
+// Some useful macros (implemented as Rust functions)
+//
+
+#[inline(always)]
+pub unsafe fn luaL_argcheck(L: *mut lua_State, cond: c_int, narg: c_int, extramsg: *const c_char) {
+    if cond == 0 {
+        luaL_argerror(L, narg, extramsg);
+    }
+}
+
+#[inline(always)]
+pub unsafe fn luaL_checkstring(L: *mut lua_State, n: c_int) -> *const c_char {
+    luaL_checklstring(L, n, ptr::null_mut())
+}
+
+#[inline(always)]
+pub unsafe fn luaL_optstring(L: *mut lua_State, n: c_int, d: *const c_char) -> *const c_char {
+    luaL_optlstring(L, n, d, ptr::null_mut())
+}
+
+// Deprecated from 5.3: luaL_checkint, luaL_optint, luaL_checklong, luaL_optlong
+
+#[inline(always)]
+pub unsafe fn luaL_typename(L: *mut lua_State, i: c_int) -> *const c_char {
+    lua::lua_typename(L, lua::lua_type(L, i))
+}
+
+pub unsafe fn luaL_dofile(L: *mut lua_State, filename: *const c_char) -> c_int {
+    let status = luaL_loadfile(L, filename);
+    if status == 0 {
+        lua::lua_pcall(L, 0, lua::LUA_MULTRET, 0)
+    } else {
+        status
+    }
+}
+
+#[inline(always)]
+pub unsafe fn luaL_dostring(L: *mut lua_State, s: *const c_char) -> c_int {
+    let status = luaL_loadstring(L, s);
+    if status == 0 {
+        lua::lua_pcall(L, 0, lua::LUA_MULTRET, 0)
+    } else {
+        status
+    }
+}
+
+#[inline(always)]
+pub unsafe fn luaL_getmetatable(L: *mut lua_State, n: *const c_char) {
+    lua::lua_getfield_(L, lua::LUA_REGISTRYINDEX, n);
+}
+
+// TODO: luaL_opt
+
+//
+// TODO: Generic Buffer Manipulation
+//

mlua-sys/src/lua51/lua.rs

@@ -0,0 +1,401 @@
+//! Contains definitions from `lua.h`.
+
+use std::ffi::CStr;
+use std::marker::{PhantomData, PhantomPinned};
+use std::os::raw::{c_char, c_double, c_int, c_void};
+use std::ptr;
+
+// Mark for precompiled code (`<esc>Lua`)
+#[cfg(not(feature = "luajit"))]
+pub const LUA_SIGNATURE: &[u8] = b"\x1bLua";
+#[cfg(feature = "luajit")]
+pub const LUA_SIGNATURE: &[u8] = b"\x1bLJ";
+
+// Option for multiple returns in 'lua_pcall' and 'lua_call'
+pub const LUA_MULTRET: c_int = -1;
+
+//
+// Pseudo-indices
+//
+pub const LUA_REGISTRYINDEX: c_int = -10000;
+pub const LUA_ENVIRONINDEX: c_int = -10001;
+pub const LUA_GLOBALSINDEX: c_int = -10002;
+
+pub const fn lua_upvalueindex(i: c_int) -> c_int {
+    LUA_GLOBALSINDEX - i
+}
+
+//
+// Thread status
+//
+pub const LUA_OK: c_int = 0;
+pub const LUA_YIELD: c_int = 1;
+pub const LUA_ERRRUN: c_int = 2;
+pub const LUA_ERRSYNTAX: c_int = 3;
+pub const LUA_ERRMEM: c_int = 4;
+pub const LUA_ERRERR: c_int = 5;
+
+/// A raw Lua state associated with a thread.
+#[repr(C)]
+pub struct lua_State {
+    _data: [u8; 0],
+    _marker: PhantomData<(*mut u8, PhantomPinned)>,
+}
+
+//
+// Basic types
+//
+pub const LUA_TNONE: c_int = -1;
+
+pub const LUA_TNIL: c_int = 0;
+pub const LUA_TBOOLEAN: c_int = 1;
+pub const LUA_TLIGHTUSERDATA: c_int = 2;
+pub const LUA_TNUMBER: c_int = 3;
+pub const LUA_TSTRING: c_int = 4;
+pub const LUA_TTABLE: c_int = 5;
+pub const LUA_TFUNCTION: c_int = 6;
+pub const LUA_TUSERDATA: c_int = 7;
+pub const LUA_TTHREAD: c_int = 8;
+
+/// Type produced by LuaJIT FFI module
+#[cfg(feature = "luajit")]
+pub const LUA_TCDATA: c_int = 10;
+
+/// Minimum Lua stack available to a C function
+pub const LUA_MINSTACK: c_int = 20;
+
+/// A Lua number, usually equivalent to `f64`
+pub type lua_Number = c_double;
+
+/// A Lua integer, usually equivalent to `i64`
+#[cfg(target_pointer_width = "32")]
+pub type lua_Integer = i32;
+#[cfg(target_pointer_width = "64")]
+pub type lua_Integer = i64;
+
+/// Type for native C functions that can be passed to Lua.
+pub type lua_CFunction = unsafe extern "C-unwind" fn(L: *mut lua_State) -> c_int;
+
+// Type for functions that read/write blocks when loading/dumping Lua chunks
+#[rustfmt::skip]
+pub type lua_Reader =
+    unsafe extern "C-unwind" fn(L: *mut lua_State, ud: *mut c_void, sz: *mut usize) -> *const c_char;
+#[rustfmt::skip]
+pub type lua_Writer =
+    unsafe extern "C-unwind" fn(L: *mut lua_State, p: *const c_void, sz: usize, ud: *mut c_void) -> c_int;
+
+/// Type for memory-allocation functions (no unwinding)
+#[rustfmt::skip]
+pub type lua_Alloc =
+    unsafe extern "C" fn(ud: *mut c_void, ptr: *mut c_void, osize: usize, nsize: usize) -> *mut c_void;
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua51", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    //
+    // State manipulation
+    //
+    pub fn lua_newstate(f: lua_Alloc, ud: *mut c_void) -> *mut lua_State;
+    pub fn lua_close(L: *mut lua_State);
+    pub fn lua_newthread(L: *mut lua_State) -> *mut lua_State;
+
+    pub fn lua_atpanic(L: *mut lua_State, panicf: lua_CFunction) -> lua_CFunction;
+
+    //
+    // Basic stack manipulation
+    //
+    pub fn lua_gettop(L: *mut lua_State) -> c_int;
+    pub fn lua_settop(L: *mut lua_State, idx: c_int);
+    pub fn lua_pushvalue(L: *mut lua_State, idx: c_int);
+    pub fn lua_remove(L: *mut lua_State, idx: c_int);
+    pub fn lua_insert(L: *mut lua_State, idx: c_int);
+    pub fn lua_replace(L: *mut lua_State, idx: c_int);
+    pub fn lua_checkstack(L: *mut lua_State, sz: c_int) -> c_int;
+
+    pub fn lua_xmove(from: *mut lua_State, to: *mut lua_State, n: c_int);
+
+    //
+    // Access functions (stack -> C)
+    //
+    pub fn lua_isnumber(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_isstring(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_iscfunction(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_isuserdata(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_type(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_typename(L: *mut lua_State, tp: c_int) -> *const c_char;
+
+    pub fn lua_equal(L: *mut lua_State, idx1: c_int, idx2: c_int) -> c_int;
+    pub fn lua_rawequal(L: *mut lua_State, idx1: c_int, idx2: c_int) -> c_int;
+    pub fn lua_lessthan(L: *mut lua_State, idx1: c_int, idx2: c_int) -> c_int;
+
+    pub fn lua_tonumber(L: *mut lua_State, idx: c_int) -> lua_Number;
+    #[link_name = "lua_tointeger"]
+    pub fn lua_tointeger_(L: *mut lua_State, idx: c_int) -> lua_Integer;
+    pub fn lua_toboolean(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_tolstring(L: *mut lua_State, idx: c_int, len: *mut usize) -> *const c_char;
+    pub fn lua_objlen(L: *mut lua_State, idx: c_int) -> usize;
+    pub fn lua_tocfunction(L: *mut lua_State, idx: c_int) -> Option<lua_CFunction>;
+    pub fn lua_touserdata(L: *mut lua_State, idx: c_int) -> *mut c_void;
+    pub fn lua_tothread(L: *mut lua_State, idx: c_int) -> *mut lua_State;
+    pub fn lua_topointer(L: *mut lua_State, idx: c_int) -> *const c_void;
+
+    //
+    // Push functions (C -> stack)
+    //
+    pub fn lua_pushnil(L: *mut lua_State);
+    pub fn lua_pushnumber(L: *mut lua_State, n: lua_Number);
+    pub fn lua_pushinteger(L: *mut lua_State, n: lua_Integer);
+    #[link_name = "lua_pushlstring"]
+    pub fn lua_pushlstring_(L: *mut lua_State, s: *const c_char, l: usize);
+    #[link_name = "lua_pushstring"]
+    pub fn lua_pushstring_(L: *mut lua_State, s: *const c_char);
+    // lua_pushvfstring
+    pub fn lua_pushfstring(L: *mut lua_State, fmt: *const c_char, ...) -> *const c_char;
+    pub fn lua_pushcclosure(L: *mut lua_State, f: lua_CFunction, n: c_int);
+    pub fn lua_pushboolean(L: *mut lua_State, b: c_int);
+    pub fn lua_pushlightuserdata(L: *mut lua_State, p: *mut c_void);
+    pub fn lua_pushthread(L: *mut lua_State) -> c_int;
+
+    //
+    // Get functions (Lua -> stack)
+    //
+    #[link_name = "lua_gettable"]
+    pub fn lua_gettable_(L: *mut lua_State, idx: c_int);
+    #[link_name = "lua_getfield"]
+    pub fn lua_getfield_(L: *mut lua_State, idx: c_int, k: *const c_char);
+    #[link_name = "lua_rawget"]
+    pub fn lua_rawget_(L: *mut lua_State, idx: c_int);
+    #[link_name = "lua_rawgeti"]
+    pub fn lua_rawgeti_(L: *mut lua_State, idx: c_int, n: c_int);
+    pub fn lua_createtable(L: *mut lua_State, narr: c_int, nrec: c_int);
+    pub fn lua_newuserdata(L: *mut lua_State, sz: usize) -> *mut c_void;
+    pub fn lua_getmetatable(L: *mut lua_State, objindex: c_int) -> c_int;
+    pub fn lua_getfenv(L: *mut lua_State, idx: c_int);
+
+    //
+    // Set functions (stack -> Lua)
+    //
+    pub fn lua_settable(L: *mut lua_State, idx: c_int);
+    pub fn lua_setfield(L: *mut lua_State, idx: c_int, k: *const c_char);
+    pub fn lua_rawset(L: *mut lua_State, idx: c_int);
+    #[link_name = "lua_rawseti"]
+    pub fn lua_rawseti_(L: *mut lua_State, idx: c_int, n: c_int);
+    pub fn lua_setmetatable(L: *mut lua_State, objindex: c_int) -> c_int;
+    pub fn lua_setfenv(L: *mut lua_State, idx: c_int) -> c_int;
+
+    //
+    // 'load' and 'call' functions (load and run Lua code)
+    //
+    pub fn lua_call(L: *mut lua_State, nargs: c_int, nresults: c_int);
+    pub fn lua_pcall(L: *mut lua_State, nargs: c_int, nresults: c_int, errfunc: c_int) -> c_int;
+    pub fn lua_cpcall(L: *mut lua_State, f: lua_CFunction, ud: *mut c_void) -> c_int;
+    pub fn lua_load(
+        L: *mut lua_State,
+        reader: lua_Reader,
+        data: *mut c_void,
+        chunkname: *const c_char,
+    ) -> c_int;
+
+    #[link_name = "lua_dump"]
+    pub fn lua_dump_(L: *mut lua_State, writer: lua_Writer, data: *mut c_void) -> c_int;
+
+    //
+    // Coroutine functions
+    //
+    pub fn lua_yield(L: *mut lua_State, nresults: c_int) -> c_int;
+    #[link_name = "lua_resume"]
+    pub fn lua_resume_(L: *mut lua_State, narg: c_int) -> c_int;
+    pub fn lua_status(L: *mut lua_State) -> c_int;
+}
+
+//
+// Garbage-collection function and options
+//
+pub const LUA_GCSTOP: c_int = 0;
+pub const LUA_GCRESTART: c_int = 1;
+pub const LUA_GCCOLLECT: c_int = 2;
+pub const LUA_GCCOUNT: c_int = 3;
+pub const LUA_GCCOUNTB: c_int = 4;
+pub const LUA_GCSTEP: c_int = 5;
+pub const LUA_GCSETPAUSE: c_int = 6;
+pub const LUA_GCSETSTEPMUL: c_int = 7;
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua51", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    pub fn lua_gc(L: *mut lua_State, what: c_int, data: c_int) -> c_int;
+}
+
+//
+// Miscellaneous functions
+//
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua51", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    #[link_name = "lua_error"]
+    fn lua_error_(L: *mut lua_State) -> c_int;
+    pub fn lua_next(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_concat(L: *mut lua_State, n: c_int);
+    pub fn lua_getallocf(L: *mut lua_State, ud: *mut *mut c_void) -> lua_Alloc;
+    pub fn lua_setallocf(L: *mut lua_State, f: lua_Alloc, ud: *mut c_void);
+}
+
+// lua_error does not return but is declared to return int, and Rust translates
+// ! to void which can cause link-time errors if the platform linker is aware
+// of return types and requires they match (for example: wasm does this).
+#[inline(always)]
+pub unsafe fn lua_error(L: *mut lua_State) -> ! {
+    lua_error_(L);
+    unreachable!();
+}
+
+//
+// Some useful macros (implemented as Rust functions)
+//
+#[inline(always)]
+pub unsafe fn lua_pop(L: *mut lua_State, n: c_int) {
+    lua_settop(L, -n - 1)
+}
+
+#[inline(always)]
+pub unsafe fn lua_newtable(L: *mut lua_State) {
+    lua_createtable(L, 0, 0)
+}
+
+#[inline(always)]
+pub unsafe fn lua_register(L: *mut lua_State, n: *const c_char, f: lua_CFunction) {
+    lua_pushcfunction(L, f);
+    lua_setglobal(L, n)
+}
+
+#[inline(always)]
+pub unsafe fn lua_pushcfunction(L: *mut lua_State, f: lua_CFunction) {
+    lua_pushcclosure(L, f, 0)
+}
+
+// TODO: lua_strlen
+
+#[inline(always)]
+pub unsafe fn lua_isfunction(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TFUNCTION) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_istable(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TTABLE) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_islightuserdata(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TLIGHTUSERDATA) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_isnil(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TNIL) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_isboolean(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TBOOLEAN) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_isthread(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TTHREAD) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_isnone(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TNONE) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_isnoneornil(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) <= LUA_TNIL) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_pushliteral(L: *mut lua_State, s: &'static CStr) {
+    lua_pushstring_(L, s.as_ptr());
+}
+
+#[inline(always)]
+pub unsafe fn lua_setglobal(L: *mut lua_State, var: *const c_char) {
+    lua_setfield(L, LUA_GLOBALSINDEX, var)
+}
+
+#[inline(always)]
+pub unsafe fn lua_getglobal_(L: *mut lua_State, var: *const c_char) {
+    lua_getfield_(L, LUA_GLOBALSINDEX, var)
+}
+
+#[inline(always)]
+pub unsafe fn lua_tolightuserdata(L: *mut lua_State, idx: c_int) -> *mut c_void {
+    if lua_islightuserdata(L, idx) != 0 {
+        return lua_touserdata(L, idx);
+    }
+    ptr::null_mut()
+}
+
+#[inline(always)]
+pub unsafe fn lua_tostring(L: *mut lua_State, i: c_int) -> *const c_char {
+    lua_tolstring(L, i, ptr::null_mut())
+}
+
+#[inline(always)]
+pub unsafe fn lua_xpush(from: *mut lua_State, to: *mut lua_State, idx: c_int) {
+    lua_pushvalue(from, idx);
+    lua_xmove(from, to, 1);
+}
+
+//
+// Debug API
+//
+
+// Maximum size for the description of the source of a function in debug information.
+const LUA_IDSIZE: usize = 60;
+
+// Event codes
+pub const LUA_HOOKCALL: c_int = 0;
+pub const LUA_HOOKRET: c_int = 1;
+pub const LUA_HOOKLINE: c_int = 2;
+pub const LUA_HOOKCOUNT: c_int = 3;
+pub const LUA_HOOKTAILCALL: c_int = 4;
+
+// Event masks
+pub const LUA_MASKCALL: c_int = 1 << (LUA_HOOKCALL as usize);
+pub const LUA_MASKRET: c_int = 1 << (LUA_HOOKRET as usize);
+pub const LUA_MASKLINE: c_int = 1 << (LUA_HOOKLINE as usize);
+pub const LUA_MASKCOUNT: c_int = 1 << (LUA_HOOKCOUNT as usize);
+
+/// Type for functions to be called on debug events.
+pub type lua_Hook = unsafe extern "C-unwind" fn(L: *mut lua_State, ar: *mut lua_Debug);
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua51", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    pub fn lua_getstack(L: *mut lua_State, level: c_int, ar: *mut lua_Debug) -> c_int;
+    pub fn lua_getinfo(L: *mut lua_State, what: *const c_char, ar: *mut lua_Debug) -> c_int;
+    pub fn lua_getlocal(L: *mut lua_State, ar: *const lua_Debug, n: c_int) -> *const c_char;
+    pub fn lua_setlocal(L: *mut lua_State, ar: *const lua_Debug, n: c_int) -> *const c_char;
+    pub fn lua_getupvalue(L: *mut lua_State, funcindex: c_int, n: c_int) -> *const c_char;
+    pub fn lua_setupvalue(L: *mut lua_State, funcindex: c_int, n: c_int) -> *const c_char;
+
+    pub fn lua_sethook(L: *mut lua_State, func: Option<lua_Hook>, mask: c_int, count: c_int) -> c_int;
+    pub fn lua_gethook(L: *mut lua_State) -> Option<lua_Hook>;
+    pub fn lua_gethookmask(L: *mut lua_State) -> c_int;
+    pub fn lua_gethookcount(L: *mut lua_State) -> c_int;
+}
+
+#[repr(C)]
+pub struct lua_Debug {
+    pub event: c_int,
+    pub name: *const c_char,
+    pub namewhat: *const c_char,
+    pub what: *const c_char,
+    pub source: *const c_char,
+    pub currentline: c_int,
+    pub nups: c_int,
+    pub linedefined: c_int,
+    pub lastlinedefined: c_int,
+    pub short_src: [c_char; LUA_IDSIZE],
+    // lua.h mentions this is for private use
+    i_ci: c_int,
+}

mlua-sys/src/lua51/lualib.rs

@@ -0,0 +1,43 @@
+//! Contains definitions from `lualib.h`.
+
+use std::os::raw::{c_char, c_int};
+
+use super::lua::lua_State;
+
+pub const LUA_COLIBNAME: *const c_char = cstr!("coroutine");
+pub const LUA_TABLIBNAME: *const c_char = cstr!("table");
+pub const LUA_IOLIBNAME: *const c_char = cstr!("io");
+pub const LUA_OSLIBNAME: *const c_char = cstr!("os");
+pub const LUA_STRLIBNAME: *const c_char = cstr!("string");
+pub const LUA_MATHLIBNAME: *const c_char = cstr!("math");
+pub const LUA_DBLIBNAME: *const c_char = cstr!("debug");
+pub const LUA_LOADLIBNAME: *const c_char = cstr!("package");
+
+#[cfg(feature = "luajit")]
+pub const LUA_BITLIBNAME: *const c_char = cstr!("bit");
+#[cfg(feature = "luajit")]
+pub const LUA_JITLIBNAME: *const c_char = cstr!("jit");
+#[cfg(feature = "luajit")]
+pub const LUA_FFILIBNAME: *const c_char = cstr!("ffi");
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua51", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    pub fn luaopen_base(L: *mut lua_State) -> c_int;
+    pub fn luaopen_table(L: *mut lua_State) -> c_int;
+    pub fn luaopen_io(L: *mut lua_State) -> c_int;
+    pub fn luaopen_os(L: *mut lua_State) -> c_int;
+    pub fn luaopen_string(L: *mut lua_State) -> c_int;
+    pub fn luaopen_math(L: *mut lua_State) -> c_int;
+    pub fn luaopen_debug(L: *mut lua_State) -> c_int;
+    pub fn luaopen_package(L: *mut lua_State) -> c_int;
+
+    #[cfg(feature = "luajit")]
+    pub fn luaopen_bit(L: *mut lua_State) -> c_int;
+    #[cfg(feature = "luajit")]
+    pub fn luaopen_jit(L: *mut lua_State) -> c_int;
+    #[cfg(feature = "luajit")]
+    pub fn luaopen_ffi(L: *mut lua_State) -> c_int;
+
+    // open all builtin libraries
+    pub fn luaL_openlibs(L: *mut lua_State);
+}

mlua-sys/src/lua51/mod.rs

@@ -0,0 +1,11 @@
+//! Low level bindings to Lua 5.1.
+
+pub use compat::*;
+pub use lauxlib::*;
+pub use lua::*;
+pub use lualib::*;
+
+pub mod compat;
+pub mod lauxlib;
+pub mod lua;
+pub mod lualib;

mlua-sys/src/lua52/compat.rs

@@ -0,0 +1,269 @@
+//! MLua compatibility layer for Lua 5.2
+//!
+//! Based on github.com/keplerproject/lua-compat-5.3
+
+use std::os::raw::{c_char, c_int, c_void};
+use std::ptr;
+
+use super::lauxlib::*;
+use super::lua::*;
+
+#[inline(always)]
+unsafe fn compat53_reverse(L: *mut lua_State, mut a: c_int, mut b: c_int) {
+    while a < b {
+        lua_pushvalue(L, a);
+        lua_pushvalue(L, b);
+        lua_replace(L, a);
+        lua_replace(L, b);
+        a += 1;
+        b -= 1;
+    }
+}
+
+//
+// lua ported functions
+//
+
+pub unsafe fn lua_rotate(L: *mut lua_State, mut idx: c_int, mut n: c_int) {
+    idx = lua_absindex(L, idx);
+    if n > 0 {
+        // Faster version
+        for _ in 0..n {
+            lua_insert(L, idx);
+        }
+        return;
+    }
+    let n_elems = lua_gettop(L) - idx + 1;
+    if n < 0 {
+        n += n_elems;
+    }
+    if n > 0 && n < n_elems {
+        luaL_checkstack(L, 2, cstr!("not enough stack slots available"));
+        n = n_elems - n;
+        compat53_reverse(L, idx, idx + n - 1);
+        compat53_reverse(L, idx + n, idx + n_elems - 1);
+        compat53_reverse(L, idx, idx + n_elems - 1);
+    }
+}
+
+#[inline(always)]
+pub unsafe fn lua_isinteger(L: *mut lua_State, idx: c_int) -> c_int {
+    if lua_type(L, idx) == LUA_TNUMBER {
+        let n = lua_tonumber(L, idx);
+        let i = lua_tointeger(L, idx);
+        // Lua 5.3+ returns "false" for `-0.0`
+        if n.to_bits() == (i as lua_Number).to_bits() {
+            return 1;
+        }
+    }
+    0
+}
+
+#[inline(always)]
+pub unsafe fn lua_tointeger(L: *mut lua_State, i: c_int) -> lua_Integer {
+    lua_tointegerx(L, i, ptr::null_mut())
+}
+
+// Implemented for Lua 5.2 as well
+// See https://github.com/keplerproject/lua-compat-5.3/issues/40
+#[inline(always)]
+pub unsafe fn lua_tointegerx(L: *mut lua_State, i: c_int, isnum: *mut c_int) -> lua_Integer {
+    let mut ok = 0;
+    let n = lua_tonumberx(L, i, &mut ok);
+    let n_int = n as lua_Integer;
+    if ok != 0 && (n - n_int as lua_Number).abs() < lua_Number::EPSILON {
+        if !isnum.is_null() {
+            *isnum = 1;
+        }
+        return n_int;
+    }
+    if !isnum.is_null() {
+        *isnum = 0;
+    }
+    0
+}
+
+#[inline(always)]
+pub unsafe fn lua_pushlstring(L: *mut lua_State, s: *const c_char, l: usize) -> *const c_char {
+    if l == 0 {
+        lua_pushlstring_(L, cstr!(""), 0)
+    } else {
+        lua_pushlstring_(L, s, l)
+    }
+}
+
+#[inline(always)]
+pub unsafe fn lua_getglobal(L: *mut lua_State, var: *const c_char) -> c_int {
+    lua_getglobal_(L, var);
+    lua_type(L, -1)
+}
+
+#[inline(always)]
+pub unsafe fn lua_gettable(L: *mut lua_State, idx: c_int) -> c_int {
+    lua_gettable_(L, idx);
+    lua_type(L, -1)
+}
+
+#[inline(always)]
+pub unsafe fn lua_getfield(L: *mut lua_State, idx: c_int, k: *const c_char) -> c_int {
+    lua_getfield_(L, idx, k);
+    lua_type(L, -1)
+}
+
+#[inline(always)]
+pub unsafe fn lua_geti(L: *mut lua_State, mut idx: c_int, n: lua_Integer) -> c_int {
+    idx = lua_absindex(L, idx);
+    lua_pushinteger(L, n);
+    lua_gettable(L, idx)
+}
+
+#[inline(always)]
+pub unsafe fn lua_rawget(L: *mut lua_State, idx: c_int) -> c_int {
+    lua_rawget_(L, idx);
+    lua_type(L, -1)
+}
+
+#[inline(always)]
+pub unsafe fn lua_rawgeti(L: *mut lua_State, idx: c_int, n: lua_Integer) -> c_int {
+    let n = n.try_into().expect("cannot convert index to lua_Integer");
+    lua_rawgeti_(L, idx, n);
+    lua_type(L, -1)
+}
+
+#[inline(always)]
+pub unsafe fn lua_rawgetp(L: *mut lua_State, idx: c_int, p: *const c_void) -> c_int {
+    lua_rawgetp_(L, idx, p);
+    lua_type(L, -1)
+}
+
+#[inline(always)]
+pub unsafe fn lua_getuservalue(L: *mut lua_State, idx: c_int) -> c_int {
+    lua_getuservalue_(L, idx);
+    lua_type(L, -1)
+}
+
+#[inline(always)]
+pub unsafe fn lua_seti(L: *mut lua_State, mut idx: c_int, n: lua_Integer) {
+    luaL_checkstack(L, 1, cstr!("not enough stack slots available"));
+    idx = lua_absindex(L, idx);
+    lua_pushinteger(L, n);
+    lua_insert(L, -2);
+    lua_settable(L, idx);
+}
+
+#[inline(always)]
+pub unsafe fn lua_rawseti(L: *mut lua_State, idx: c_int, n: lua_Integer) {
+    let n = n.try_into().expect("cannot convert index from lua_Integer");
+    lua_rawseti_(L, idx, n)
+}
+
+#[inline(always)]
+pub unsafe fn lua_dump(L: *mut lua_State, writer: lua_Writer, data: *mut c_void, _strip: c_int) -> c_int {
+    lua_dump_(L, writer, data)
+}
+
+#[inline(always)]
+pub unsafe fn lua_resume(L: *mut lua_State, from: *mut lua_State, narg: c_int, nres: *mut c_int) -> c_int {
+    let ret = lua_resume_(L, from, narg);
+    if (ret == LUA_OK || ret == LUA_YIELD) && !(nres.is_null()) {
+        *nres = lua_gettop(L);
+    }
+    ret
+}
+
+//
+// lauxlib ported functions
+//
+
+#[inline(always)]
+pub unsafe fn luaL_getmetafield(L: *mut lua_State, obj: c_int, e: *const c_char) -> c_int {
+    if luaL_getmetafield_(L, obj, e) != 0 {
+        lua_type(L, -1)
+    } else {
+        LUA_TNIL
+    }
+}
+
+#[inline(always)]
+pub unsafe fn luaL_newmetatable(L: *mut lua_State, tname: *const c_char) -> c_int {
+    if luaL_newmetatable_(L, tname) != 0 {
+        lua_pushstring(L, tname);
+        lua_setfield(L, -2, cstr!("__name"));
+        1
+    } else {
+        0
+    }
+}
+
+pub unsafe fn luaL_tolstring(L: *mut lua_State, mut idx: c_int, len: *mut usize) -> *const c_char {
+    idx = lua_absindex(L, idx);
+    if luaL_callmeta(L, idx, cstr!("__tostring")) == 0 {
+        match lua_type(L, idx) {
+            LUA_TNIL => {
+                lua_pushliteral(L, c"nil");
+            }
+            LUA_TSTRING | LUA_TNUMBER => {
+                lua_pushvalue(L, idx);
+            }
+            LUA_TBOOLEAN => {
+                if lua_toboolean(L, idx) == 0 {
+                    lua_pushliteral(L, c"false");
+                } else {
+                    lua_pushliteral(L, c"true");
+                }
+            }
+            t => {
+                let tt = luaL_getmetafield(L, idx, cstr!("__name"));
+                let name = if tt == LUA_TSTRING {
+                    lua_tostring(L, -1)
+                } else {
+                    lua_typename(L, t)
+                };
+                lua_pushfstring(L, cstr!("%s: %p"), name, lua_topointer(L, idx));
+                if tt != LUA_TNIL {
+                    lua_replace(L, -2); // remove '__name'
+                }
+            }
+        };
+    } else if lua_isstring(L, -1) == 0 {
+        luaL_error(L, cstr!("'__tostring' must return a string"));
+    }
+    lua_tolstring(L, -1, len)
+}
+
+pub unsafe fn luaL_requiref(L: *mut lua_State, modname: *const c_char, openf: lua_CFunction, glb: c_int) {
+    luaL_checkstack(L, 3, cstr!("not enough stack slots available"));
+    luaL_getsubtable(L, LUA_REGISTRYINDEX, LUA_LOADED_TABLE);
+    if lua_getfield(L, -1, modname) == LUA_TNIL {
+        lua_pop(L, 1);
+        lua_pushcfunction(L, openf);
+        lua_pushstring(L, modname);
+        lua_call(L, 1, 1);
+        lua_pushvalue(L, -1);
+        lua_setfield(L, -3, modname);
+    }
+    if glb != 0 {
+        lua_pushvalue(L, -1);
+        lua_setglobal(L, modname);
+    }
+    lua_replace(L, -2);
+}
+
+pub unsafe fn luaL_loadbufferenv(
+    L: *mut lua_State,
+    data: *const c_char,
+    size: usize,
+    name: *const c_char,
+    mode: *const c_char,
+    mut env: c_int,
+) -> c_int {
+    if env != 0 {
+        env = lua_absindex(L, env);
+    }
+    let status = luaL_loadbufferx(L, data, size, name, mode);
+    if status == LUA_OK && env != 0 {
+        lua_pushvalue(L, env);
+        lua_setupvalue(L, -2, 1);
+    }
+    status
+}

mlua-sys/src/lua52/lauxlib.rs

@@ -0,0 +1,178 @@
+//! Contains definitions from `lauxlib.h`.
+
+use std::os::raw::{c_char, c_int, c_void};
+use std::ptr;
+
+use super::lua::{self, lua_CFunction, lua_Integer, lua_Number, lua_State, lua_Unsigned};
+
+// Extra error code for 'luaL_load'
+pub const LUA_ERRFILE: c_int = lua::LUA_ERRERR + 1;
+
+// Key, in the registry, for table of loaded modules
+pub const LUA_LOADED_TABLE: *const c_char = cstr!("_LOADED");
+
+// Key, in the registry, for table of preloaded loaders
+pub const LUA_PRELOAD_TABLE: *const c_char = cstr!("_PRELOAD");
+
+#[repr(C)]
+pub struct luaL_Reg {
+    pub name: *const c_char,
+    pub func: lua_CFunction,
+}
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua52", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    pub fn luaL_checkversion_(L: *mut lua_State, ver: lua_Number);
+
+    #[link_name = "luaL_getmetafield"]
+    pub fn luaL_getmetafield_(L: *mut lua_State, obj: c_int, e: *const c_char) -> c_int;
+    pub fn luaL_callmeta(L: *mut lua_State, obj: c_int, e: *const c_char) -> c_int;
+    #[link_name = "luaL_tolstring"]
+    pub fn luaL_tolstring_(L: *mut lua_State, idx: c_int, len: *mut usize) -> *const c_char;
+    pub fn luaL_argerror(L: *mut lua_State, arg: c_int, extramsg: *const c_char) -> c_int;
+    pub fn luaL_checklstring(L: *mut lua_State, arg: c_int, l: *mut usize) -> *const c_char;
+    pub fn luaL_optlstring(L: *mut lua_State, arg: c_int, def: *const c_char, l: *mut usize)
+        -> *const c_char;
+    pub fn luaL_checknumber(L: *mut lua_State, arg: c_int) -> lua_Number;
+    pub fn luaL_optnumber(L: *mut lua_State, arg: c_int, def: lua_Number) -> lua_Number;
+    pub fn luaL_checkinteger(L: *mut lua_State, arg: c_int) -> lua_Integer;
+    pub fn luaL_optinteger(L: *mut lua_State, arg: c_int, def: lua_Integer) -> lua_Integer;
+    pub fn luaL_checkunsigned(L: *mut lua_State, arg: c_int) -> lua_Unsigned;
+    pub fn luaL_optunsigned(L: *mut lua_State, arg: c_int, def: lua_Unsigned) -> lua_Unsigned;
+
+    pub fn luaL_checkstack(L: *mut lua_State, sz: c_int, msg: *const c_char);
+    pub fn luaL_checktype(L: *mut lua_State, arg: c_int, t: c_int);
+    pub fn luaL_checkany(L: *mut lua_State, arg: c_int);
+
+    #[link_name = "luaL_newmetatable"]
+    pub fn luaL_newmetatable_(L: *mut lua_State, tname: *const c_char) -> c_int;
+    pub fn luaL_setmetatable(L: *mut lua_State, tname: *const c_char);
+    pub fn luaL_testudata(L: *mut lua_State, ud: c_int, tname: *const c_char) -> *mut c_void;
+    pub fn luaL_checkudata(L: *mut lua_State, ud: c_int, tname: *const c_char) -> *mut c_void;
+
+    pub fn luaL_where(L: *mut lua_State, lvl: c_int);
+    pub fn luaL_error(L: *mut lua_State, fmt: *const c_char, ...) -> c_int;
+
+    pub fn luaL_checkoption(
+        L: *mut lua_State,
+        arg: c_int,
+        def: *const c_char,
+        lst: *const *const c_char,
+    ) -> c_int;
+
+    pub fn luaL_fileresult(L: *mut lua_State, stat: c_int, fname: *const c_char) -> c_int;
+    pub fn luaL_execresult(L: *mut lua_State, stat: c_int) -> c_int;
+}
+
+// Pre-defined references
+pub const LUA_NOREF: c_int = -2;
+pub const LUA_REFNIL: c_int = -1;
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua52", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    pub fn luaL_ref(L: *mut lua_State, t: c_int) -> c_int;
+    pub fn luaL_unref(L: *mut lua_State, t: c_int, r#ref: c_int);
+
+    pub fn luaL_loadfilex(L: *mut lua_State, filename: *const c_char, mode: *const c_char) -> c_int;
+}
+
+#[inline(always)]
+pub unsafe fn luaL_loadfile(L: *mut lua_State, f: *const c_char) -> c_int {
+    luaL_loadfilex(L, f, ptr::null())
+}
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua52", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    pub fn luaL_loadbufferx(
+        L: *mut lua_State,
+        buff: *const c_char,
+        sz: usize,
+        name: *const c_char,
+        mode: *const c_char,
+    ) -> c_int;
+    pub fn luaL_loadstring(L: *mut lua_State, s: *const c_char) -> c_int;
+
+    pub fn luaL_newstate() -> *mut lua_State;
+
+    pub fn luaL_len(L: *mut lua_State, idx: c_int) -> lua_Integer;
+
+    pub fn luaL_gsub(
+        L: *mut lua_State,
+        s: *const c_char,
+        p: *const c_char,
+        r: *const c_char,
+    ) -> *const c_char;
+
+    pub fn luaL_setfuncs(L: *mut lua_State, l: *const luaL_Reg, nup: c_int);
+
+    pub fn luaL_getsubtable(L: *mut lua_State, idx: c_int, fname: *const c_char) -> c_int;
+
+    pub fn luaL_traceback(L: *mut lua_State, L1: *mut lua_State, msg: *const c_char, level: c_int);
+
+    #[link_name = "luaL_requiref"]
+    pub fn luaL_requiref_(L: *mut lua_State, modname: *const c_char, openf: lua_CFunction, glb: c_int);
+}
+
+//
+// Some useful macros (implemented as Rust functions)
+//
+
+// TODO: luaL_newlibtable, luaL_newlib
+
+#[inline(always)]
+pub unsafe fn luaL_argcheck(L: *mut lua_State, cond: c_int, arg: c_int, extramsg: *const c_char) {
+    if cond == 0 {
+        luaL_argerror(L, arg, extramsg);
+    }
+}
+
+#[inline(always)]
+pub unsafe fn luaL_checkstring(L: *mut lua_State, n: c_int) -> *const c_char {
+    luaL_checklstring(L, n, ptr::null_mut())
+}
+
+#[inline(always)]
+pub unsafe fn luaL_optstring(L: *mut lua_State, n: c_int, d: *const c_char) -> *const c_char {
+    luaL_optlstring(L, n, d, ptr::null_mut())
+}
+
+#[inline(always)]
+pub unsafe fn luaL_typename(L: *mut lua_State, i: c_int) -> *const c_char {
+    lua::lua_typename(L, lua::lua_type(L, i))
+}
+
+#[inline(always)]
+pub unsafe fn luaL_dofile(L: *mut lua_State, filename: *const c_char) -> c_int {
+    let status = luaL_loadfile(L, filename);
+    if status == 0 {
+        lua::lua_pcall(L, 0, lua::LUA_MULTRET, 0)
+    } else {
+        status
+    }
+}
+
+#[inline(always)]
+pub unsafe fn luaL_dostring(L: *mut lua_State, s: *const c_char) -> c_int {
+    let status = luaL_loadstring(L, s);
+    if status == 0 {
+        lua::lua_pcall(L, 0, lua::LUA_MULTRET, 0)
+    } else {
+        status
+    }
+}
+
+#[inline(always)]
+pub unsafe fn luaL_getmetatable(L: *mut lua_State, n: *const c_char) {
+    lua::lua_getfield_(L, lua::LUA_REGISTRYINDEX, n);
+}
+
+// luaL_opt would be implemented here but it is undocumented, so it's omitted
+
+#[inline(always)]
+pub unsafe fn luaL_loadbuffer(L: *mut lua_State, s: *const c_char, sz: usize, n: *const c_char) -> c_int {
+    luaL_loadbufferx(L, s, sz, n, ptr::null())
+}
+
+//
+// TODO: Generic Buffer Manipulation
+//

mlua-sys/src/lua52/lua.rs

@@ -0,0 +1,485 @@
+//! Contains definitions from `lua.h`.
+
+use std::ffi::CStr;
+use std::marker::{PhantomData, PhantomPinned};
+use std::os::raw::{c_char, c_double, c_int, c_uchar, c_uint, c_void};
+use std::ptr;
+
+// Mark for precompiled code (`<esc>Lua`)
+pub const LUA_SIGNATURE: &[u8] = b"\x1bLua";
+
+// Option for multiple returns in 'lua_pcall' and 'lua_call'
+pub const LUA_MULTRET: c_int = -1;
+
+// Size of the Lua stack
+pub const LUAI_MAXSTACK: c_int = 1000000;
+
+//
+// Pseudo-indices
+//
+pub const LUA_REGISTRYINDEX: c_int = -LUAI_MAXSTACK - 1000;
+
+pub const fn lua_upvalueindex(i: c_int) -> c_int {
+    LUA_REGISTRYINDEX - i
+}
+
+//
+// Thread status
+//
+pub const LUA_OK: c_int = 0;
+pub const LUA_YIELD: c_int = 1;
+pub const LUA_ERRRUN: c_int = 2;
+pub const LUA_ERRSYNTAX: c_int = 3;
+pub const LUA_ERRMEM: c_int = 4;
+pub const LUA_ERRGCMM: c_int = 5;
+pub const LUA_ERRERR: c_int = 6;
+
+/// A raw Lua state associated with a thread.
+#[repr(C)]
+pub struct lua_State {
+    _data: [u8; 0],
+    _marker: PhantomData<(*mut u8, PhantomPinned)>,
+}
+
+//
+// Basic types
+//
+pub const LUA_TNONE: c_int = -1;
+
+pub const LUA_TNIL: c_int = 0;
+pub const LUA_TBOOLEAN: c_int = 1;
+pub const LUA_TLIGHTUSERDATA: c_int = 2;
+pub const LUA_TNUMBER: c_int = 3;
+pub const LUA_TSTRING: c_int = 4;
+pub const LUA_TTABLE: c_int = 5;
+pub const LUA_TFUNCTION: c_int = 6;
+pub const LUA_TUSERDATA: c_int = 7;
+pub const LUA_TTHREAD: c_int = 8;
+
+pub const LUA_NUMTAGS: c_int = 9;
+
+/// Minimum Lua stack available to a C function
+pub const LUA_MINSTACK: c_int = 20;
+
+// Predefined values in the registry
+pub const LUA_RIDX_MAINTHREAD: lua_Integer = 1;
+pub const LUA_RIDX_GLOBALS: lua_Integer = 2;
+pub const LUA_RIDX_LAST: lua_Integer = LUA_RIDX_GLOBALS;
+
+/// A Lua number, usually equivalent to `f64`
+pub type lua_Number = c_double;
+
+/// A Lua integer, usually equivalent to `i64`
+#[cfg(target_pointer_width = "32")]
+pub type lua_Integer = i32;
+#[cfg(target_pointer_width = "64")]
+pub type lua_Integer = i64;
+
+/// A Lua unsigned integer, equivalent to `u32` in Lua 5.2
+pub type lua_Unsigned = c_uint;
+
+/// Type for native C functions that can be passed to Lua
+pub type lua_CFunction = unsafe extern "C-unwind" fn(L: *mut lua_State) -> c_int;
+
+// Type for functions that read/write blocks when loading/dumping Lua chunks
+#[rustfmt::skip]
+pub type lua_Reader =
+    unsafe extern "C-unwind" fn(L: *mut lua_State, ud: *mut c_void, sz: *mut usize) -> *const c_char;
+#[rustfmt::skip]
+pub type lua_Writer =
+    unsafe extern "C-unwind" fn(L: *mut lua_State, p: *const c_void, sz: usize, ud: *mut c_void) -> c_int;
+
+/// Type for memory-allocation functions (no unwinding)
+#[rustfmt::skip]
+pub type lua_Alloc =
+    unsafe extern "C" fn(ud: *mut c_void, ptr: *mut c_void, osize: usize, nsize: usize) -> *mut c_void;
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua52", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    //
+    // State manipulation
+    //
+    pub fn lua_newstate(f: lua_Alloc, ud: *mut c_void) -> *mut lua_State;
+    pub fn lua_close(L: *mut lua_State);
+    pub fn lua_newthread(L: *mut lua_State) -> *mut lua_State;
+
+    pub fn lua_atpanic(L: *mut lua_State, panicf: lua_CFunction) -> lua_CFunction;
+
+    pub fn lua_version(L: *mut lua_State) -> *const lua_Number;
+
+    //
+    // Basic stack manipulation
+    //
+    pub fn lua_absindex(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_gettop(L: *mut lua_State) -> c_int;
+    pub fn lua_settop(L: *mut lua_State, idx: c_int);
+    pub fn lua_pushvalue(L: *mut lua_State, idx: c_int);
+    pub fn lua_remove(L: *mut lua_State, idx: c_int);
+    pub fn lua_insert(L: *mut lua_State, idx: c_int);
+    pub fn lua_replace(L: *mut lua_State, idx: c_int);
+    pub fn lua_copy(L: *mut lua_State, fromidx: c_int, toidx: c_int);
+    pub fn lua_checkstack(L: *mut lua_State, sz: c_int) -> c_int;
+
+    pub fn lua_xmove(from: *mut lua_State, to: *mut lua_State, n: c_int);
+
+    //
+    // Access functions (stack -> C)
+    //
+    pub fn lua_isnumber(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_isstring(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_iscfunction(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_isuserdata(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_type(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_typename(L: *mut lua_State, tp: c_int) -> *const c_char;
+
+    pub fn lua_tonumberx(L: *mut lua_State, idx: c_int, isnum: *mut c_int) -> lua_Number;
+    #[link_name = "lua_tointegerx"]
+    pub fn lua_tointegerx_(L: *mut lua_State, idx: c_int, isnum: *mut c_int) -> lua_Integer;
+    pub fn lua_tounsignedx(L: *mut lua_State, idx: c_int, isnum: *mut c_int) -> lua_Unsigned;
+    pub fn lua_toboolean(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_tolstring(L: *mut lua_State, idx: c_int, len: *mut usize) -> *const c_char;
+    pub fn lua_rawlen(L: *mut lua_State, idx: c_int) -> usize;
+    pub fn lua_tocfunction(L: *mut lua_State, idx: c_int) -> Option<lua_CFunction>;
+    pub fn lua_touserdata(L: *mut lua_State, idx: c_int) -> *mut c_void;
+    pub fn lua_tothread(L: *mut lua_State, idx: c_int) -> *mut lua_State;
+    pub fn lua_topointer(L: *mut lua_State, idx: c_int) -> *const c_void;
+}
+
+//
+// Comparison and arithmetic functions
+//
+pub const LUA_OPADD: c_int = 0;
+pub const LUA_OPSUB: c_int = 1;
+pub const LUA_OPMUL: c_int = 2;
+pub const LUA_OPDIV: c_int = 3;
+pub const LUA_OPMOD: c_int = 4;
+pub const LUA_OPPOW: c_int = 5;
+pub const LUA_OPUNM: c_int = 6;
+
+pub const LUA_OPEQ: c_int = 0;
+pub const LUA_OPLT: c_int = 1;
+pub const LUA_OPLE: c_int = 2;
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua52", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    pub fn lua_arith(L: *mut lua_State, op: c_int);
+    pub fn lua_rawequal(L: *mut lua_State, idx1: c_int, idx2: c_int) -> c_int;
+    pub fn lua_compare(L: *mut lua_State, idx1: c_int, idx2: c_int, op: c_int) -> c_int;
+}
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua52", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    //
+    // Push functions (C -> stack)
+    //
+    pub fn lua_pushnil(L: *mut lua_State);
+    pub fn lua_pushnumber(L: *mut lua_State, n: lua_Number);
+    pub fn lua_pushinteger(L: *mut lua_State, n: lua_Integer);
+    pub fn lua_pushunsigned(L: *mut lua_State, n: lua_Unsigned);
+    #[link_name = "lua_pushlstring"]
+    pub fn lua_pushlstring_(L: *mut lua_State, s: *const c_char, l: usize) -> *const c_char;
+    pub fn lua_pushstring(L: *mut lua_State, s: *const c_char) -> *const c_char;
+    // lua_pushvfstring
+    pub fn lua_pushfstring(L: *mut lua_State, fmt: *const c_char, ...) -> *const c_char;
+    pub fn lua_pushcclosure(L: *mut lua_State, f: lua_CFunction, n: c_int);
+    pub fn lua_pushboolean(L: *mut lua_State, b: c_int);
+    pub fn lua_pushlightuserdata(L: *mut lua_State, p: *mut c_void);
+    pub fn lua_pushthread(L: *mut lua_State) -> c_int;
+
+    //
+    // Get functions (Lua -> stack)
+    //
+    #[link_name = "lua_getglobal"]
+    pub fn lua_getglobal_(L: *mut lua_State, name: *const c_char);
+    #[link_name = "lua_gettable"]
+    pub fn lua_gettable_(L: *mut lua_State, idx: c_int);
+    #[link_name = "lua_getfield"]
+    pub fn lua_getfield_(L: *mut lua_State, idx: c_int, k: *const c_char);
+    #[link_name = "lua_rawget"]
+    pub fn lua_rawget_(L: *mut lua_State, idx: c_int);
+    #[link_name = "lua_rawgeti"]
+    pub fn lua_rawgeti_(L: *mut lua_State, idx: c_int, n: c_int);
+    #[link_name = "lua_rawgetp"]
+    pub fn lua_rawgetp_(L: *mut lua_State, idx: c_int, p: *const c_void);
+    pub fn lua_createtable(L: *mut lua_State, narr: c_int, nrec: c_int);
+    pub fn lua_newuserdata(L: *mut lua_State, sz: usize) -> *mut c_void;
+    pub fn lua_getmetatable(L: *mut lua_State, objindex: c_int) -> c_int;
+    #[link_name = "lua_getuservalue"]
+    pub fn lua_getuservalue_(L: *mut lua_State, idx: c_int);
+
+    //
+    // Set functions (stack -> Lua)
+    //
+    pub fn lua_setglobal(L: *mut lua_State, var: *const c_char);
+    pub fn lua_settable(L: *mut lua_State, idx: c_int);
+    pub fn lua_setfield(L: *mut lua_State, idx: c_int, k: *const c_char);
+    pub fn lua_rawset(L: *mut lua_State, idx: c_int);
+    #[link_name = "lua_rawseti"]
+    pub fn lua_rawseti_(L: *mut lua_State, idx: c_int, n: c_int);
+    pub fn lua_rawsetp(L: *mut lua_State, idx: c_int, p: *const c_void);
+    pub fn lua_setmetatable(L: *mut lua_State, objindex: c_int) -> c_int;
+    pub fn lua_setuservalue(L: *mut lua_State, idx: c_int);
+
+    //
+    // 'load' and 'call' functions (load and run Lua code)
+    //
+    pub fn lua_callk(L: *mut lua_State, nargs: c_int, nresults: c_int, ctx: c_int, k: Option<lua_CFunction>);
+    pub fn lua_pcallk(
+        L: *mut lua_State,
+        nargs: c_int,
+        nresults: c_int,
+        errfunc: c_int,
+        ctx: c_int,
+        k: Option<lua_CFunction>,
+    ) -> c_int;
+
+    pub fn lua_getctx(L: *mut lua_State, ctx: *mut c_int) -> c_int;
+
+    pub fn lua_load(
+        L: *mut lua_State,
+        reader: lua_Reader,
+        data: *mut c_void,
+        chunkname: *const c_char,
+        mode: *const c_char,
+    ) -> c_int;
+    #[link_name = "lua_dump"]
+    pub fn lua_dump_(L: *mut lua_State, writer: lua_Writer, data: *mut c_void) -> c_int;
+}
+
+#[inline(always)]
+pub unsafe fn lua_call(L: *mut lua_State, n: c_int, r: c_int) {
+    lua_callk(L, n, r, 0, None)
+}
+
+#[inline(always)]
+pub unsafe fn lua_pcall(L: *mut lua_State, n: c_int, r: c_int, f: c_int) -> c_int {
+    lua_pcallk(L, n, r, f, 0, None)
+}
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua52", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    //
+    // Coroutine functions
+    //
+    pub fn lua_yieldk(L: *mut lua_State, nresults: c_int, ctx: c_int, k: Option<lua_CFunction>) -> c_int;
+    #[link_name = "lua_resume"]
+    pub fn lua_resume_(L: *mut lua_State, from: *mut lua_State, narg: c_int) -> c_int;
+    pub fn lua_status(L: *mut lua_State) -> c_int;
+}
+
+#[inline(always)]
+pub unsafe fn lua_yield(L: *mut lua_State, n: c_int) -> c_int {
+    lua_yieldk(L, n, 0, None)
+}
+
+//
+// Garbage-collection function and options
+//
+pub const LUA_GCSTOP: c_int = 0;
+pub const LUA_GCRESTART: c_int = 1;
+pub const LUA_GCCOLLECT: c_int = 2;
+pub const LUA_GCCOUNT: c_int = 3;
+pub const LUA_GCCOUNTB: c_int = 4;
+pub const LUA_GCSTEP: c_int = 5;
+pub const LUA_GCSETPAUSE: c_int = 6;
+pub const LUA_GCSETSTEPMUL: c_int = 7;
+pub const LUA_GCSETMAJORINC: c_int = 8;
+pub const LUA_GCISRUNNING: c_int = 9;
+pub const LUA_GCGEN: c_int = 10;
+pub const LUA_GCINC: c_int = 11;
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua52", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    pub fn lua_gc(L: *mut lua_State, what: c_int, data: c_int) -> c_int;
+}
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua52", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    //
+    // Miscellaneous functions
+    //
+    #[link_name = "lua_error"]
+    fn lua_error_(L: *mut lua_State) -> c_int;
+    pub fn lua_next(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_concat(L: *mut lua_State, n: c_int);
+    pub fn lua_len(L: *mut lua_State, idx: c_int);
+    pub fn lua_getallocf(L: *mut lua_State, ud: *mut *mut c_void) -> lua_Alloc;
+    pub fn lua_setallocf(L: *mut lua_State, f: lua_Alloc, ud: *mut c_void);
+}
+
+// lua_error does not return but is declared to return int, and Rust translates
+// ! to void which can cause link-time errors if the platform linker is aware
+// of return types and requires they match (for example: wasm does this).
+#[inline(always)]
+pub unsafe fn lua_error(L: *mut lua_State) -> ! {
+    lua_error_(L);
+    unreachable!();
+}
+
+//
+// Some useful macros (implemented as Rust functions)
+//
+#[inline(always)]
+pub unsafe fn lua_tonumber(L: *mut lua_State, i: c_int) -> lua_Number {
+    lua_tonumberx(L, i, ptr::null_mut())
+}
+
+#[inline(always)]
+pub unsafe fn lua_tointeger_(L: *mut lua_State, i: c_int) -> lua_Integer {
+    lua_tointegerx_(L, i, ptr::null_mut())
+}
+
+#[inline(always)]
+pub unsafe fn lua_tounsigned(L: *mut lua_State, i: c_int) -> lua_Unsigned {
+    lua_tounsignedx(L, i, ptr::null_mut())
+}
+
+#[inline(always)]
+pub unsafe fn lua_pop(L: *mut lua_State, n: c_int) {
+    lua_settop(L, -n - 1)
+}
+
+#[inline(always)]
+pub unsafe fn lua_newtable(L: *mut lua_State) {
+    lua_createtable(L, 0, 0)
+}
+
+#[inline(always)]
+pub unsafe fn lua_register(L: *mut lua_State, n: *const c_char, f: lua_CFunction) {
+    lua_pushcfunction(L, f);
+    lua_setglobal(L, n)
+}
+
+#[inline(always)]
+pub unsafe fn lua_pushcfunction(L: *mut lua_State, f: lua_CFunction) {
+    lua_pushcclosure(L, f, 0)
+}
+
+#[inline(always)]
+pub unsafe fn lua_isfunction(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TFUNCTION) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_istable(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TTABLE) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_islightuserdata(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TLIGHTUSERDATA) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_isnil(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TNIL) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_isboolean(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TBOOLEAN) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_isthread(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TTHREAD) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_isnone(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TNONE) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_isnoneornil(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) <= 0) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_pushliteral(L: *mut lua_State, s: &'static CStr) {
+    lua_pushstring(L, s.as_ptr());
+}
+
+#[inline(always)]
+pub unsafe fn lua_pushglobaltable(L: *mut lua_State) {
+    lua_rawgeti_(L, LUA_REGISTRYINDEX, LUA_RIDX_GLOBALS as _)
+}
+
+#[inline(always)]
+pub unsafe fn lua_tolightuserdata(L: *mut lua_State, idx: c_int) -> *mut c_void {
+    if lua_islightuserdata(L, idx) != 0 {
+        return lua_touserdata(L, idx);
+    }
+    ptr::null_mut()
+}
+
+#[inline(always)]
+pub unsafe fn lua_tostring(L: *mut lua_State, i: c_int) -> *const c_char {
+    lua_tolstring(L, i, ptr::null_mut())
+}
+
+#[inline(always)]
+pub unsafe fn lua_xpush(from: *mut lua_State, to: *mut lua_State, idx: c_int) {
+    lua_pushvalue(from, idx);
+    lua_xmove(from, to, 1);
+}
+
+//
+// Debug API
+//
+
+// Maximum size for the description of the source of a function in debug information.
+const LUA_IDSIZE: usize = 60;
+
+// Event codes
+pub const LUA_HOOKCALL: c_int = 0;
+pub const LUA_HOOKRET: c_int = 1;
+pub const LUA_HOOKLINE: c_int = 2;
+pub const LUA_HOOKCOUNT: c_int = 3;
+pub const LUA_HOOKTAILCALL: c_int = 4;
+
+// Event masks
+pub const LUA_MASKCALL: c_int = 1 << (LUA_HOOKCALL as usize);
+pub const LUA_MASKRET: c_int = 1 << (LUA_HOOKRET as usize);
+pub const LUA_MASKLINE: c_int = 1 << (LUA_HOOKLINE as usize);
+pub const LUA_MASKCOUNT: c_int = 1 << (LUA_HOOKCOUNT as usize);
+
+/// Type for functions to be called on debug events.
+pub type lua_Hook = unsafe extern "C-unwind" fn(L: *mut lua_State, ar: *mut lua_Debug);
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua52", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    pub fn lua_getstack(L: *mut lua_State, level: c_int, ar: *mut lua_Debug) -> c_int;
+    pub fn lua_getinfo(L: *mut lua_State, what: *const c_char, ar: *mut lua_Debug) -> c_int;
+    pub fn lua_getlocal(L: *mut lua_State, ar: *const lua_Debug, n: c_int) -> *const c_char;
+    pub fn lua_setlocal(L: *mut lua_State, ar: *const lua_Debug, n: c_int) -> *const c_char;
+    pub fn lua_getupvalue(L: *mut lua_State, funcindex: c_int, n: c_int) -> *const c_char;
+    pub fn lua_setupvalue(L: *mut lua_State, funcindex: c_int, n: c_int) -> *const c_char;
+
+    pub fn lua_upvalueid(L: *mut lua_State, fidx: c_int, n: c_int) -> *mut c_void;
+    pub fn lua_upvaluejoin(L: *mut lua_State, fidx1: c_int, n1: c_int, fidx2: c_int, n2: c_int);
+
+    pub fn lua_sethook(L: *mut lua_State, func: Option<lua_Hook>, mask: c_int, count: c_int) -> c_int;
+    pub fn lua_gethook(L: *mut lua_State) -> Option<lua_Hook>;
+    pub fn lua_gethookmask(L: *mut lua_State) -> c_int;
+    pub fn lua_gethookcount(L: *mut lua_State) -> c_int;
+}
+
+#[repr(C)]
+pub struct lua_Debug {
+    pub event: c_int,
+    pub name: *const c_char,
+    pub namewhat: *const c_char,
+    pub what: *const c_char,
+    pub source: *const c_char,
+    pub currentline: c_int,
+    pub linedefined: c_int,
+    pub lastlinedefined: c_int,
+    pub nups: c_uchar,
+    pub nparams: c_uchar,
+    pub isvararg: c_char,
+    pub istailcall: c_char,
+    pub short_src: [c_char; LUA_IDSIZE],
+    // lua.h mentions this is for private use
+    i_ci: *mut c_void,
+}

mlua-sys/src/lua52/lualib.rs

@@ -0,0 +1,32 @@
+//! Contains definitions from `lualib.h`.
+
+use std::os::raw::{c_char, c_int};
+
+use super::lua::lua_State;
+
+pub const LUA_COLIBNAME: *const c_char = cstr!("coroutine");
+pub const LUA_TABLIBNAME: *const c_char = cstr!("table");
+pub const LUA_IOLIBNAME: *const c_char = cstr!("io");
+pub const LUA_OSLIBNAME: *const c_char = cstr!("os");
+pub const LUA_STRLIBNAME: *const c_char = cstr!("string");
+pub const LUA_BITLIBNAME: *const c_char = cstr!("bit32");
+pub const LUA_MATHLIBNAME: *const c_char = cstr!("math");
+pub const LUA_DBLIBNAME: *const c_char = cstr!("debug");
+pub const LUA_LOADLIBNAME: *const c_char = cstr!("package");
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua52", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    pub fn luaopen_base(L: *mut lua_State) -> c_int;
+    pub fn luaopen_coroutine(L: *mut lua_State) -> c_int;
+    pub fn luaopen_table(L: *mut lua_State) -> c_int;
+    pub fn luaopen_io(L: *mut lua_State) -> c_int;
+    pub fn luaopen_os(L: *mut lua_State) -> c_int;
+    pub fn luaopen_string(L: *mut lua_State) -> c_int;
+    pub fn luaopen_bit32(L: *mut lua_State) -> c_int;
+    pub fn luaopen_math(L: *mut lua_State) -> c_int;
+    pub fn luaopen_debug(L: *mut lua_State) -> c_int;
+    pub fn luaopen_package(L: *mut lua_State) -> c_int;
+
+    // open all builtin libraries
+    pub fn luaL_openlibs(L: *mut lua_State);
+}

mlua-sys/src/lua52/mod.rs

@@ -0,0 +1,11 @@
+//! Low level bindings to Lua 5.2.
+
+pub use compat::*;
+pub use lauxlib::*;
+pub use lua::*;
+pub use lualib::*;
+
+pub mod compat;
+pub mod lauxlib;
+pub mod lua;
+pub mod lualib;

mlua-sys/src/lua53/compat.rs

@@ -0,0 +1,34 @@
+//! MLua compatibility layer for Lua 5.3
+
+use std::os::raw::{c_char, c_int};
+
+use super::lauxlib::*;
+use super::lua::*;
+
+#[inline(always)]
+pub unsafe fn lua_resume(L: *mut lua_State, from: *mut lua_State, narg: c_int, nres: *mut c_int) -> c_int {
+    let ret = lua_resume_(L, from, narg);
+    if (ret == LUA_OK || ret == LUA_YIELD) && !(nres.is_null()) {
+        *nres = lua_gettop(L);
+    }
+    ret
+}
+
+pub unsafe fn luaL_loadbufferenv(
+    L: *mut lua_State,
+    data: *const c_char,
+    size: usize,
+    name: *const c_char,
+    mode: *const c_char,
+    mut env: c_int,
+) -> c_int {
+    if env != 0 {
+        env = lua_absindex(L, env);
+    }
+    let status = luaL_loadbufferx(L, data, size, name, mode);
+    if status == LUA_OK && env != 0 {
+        lua_pushvalue(L, env);
+        lua_setupvalue(L, -2, 1);
+    }
+    status
+}

mlua-sys/src/lua53/lauxlib.rs

@@ -0,0 +1,178 @@
+//! Contains definitions from `lauxlib.h`.
+
+use std::os::raw::{c_char, c_int, c_void};
+use std::ptr;
+
+use super::lua::{self, lua_CFunction, lua_Integer, lua_Number, lua_State};
+
+// Extra error code for 'luaL_loadfilex'
+pub const LUA_ERRFILE: c_int = lua::LUA_ERRERR + 1;
+
+// Key, in the registry, for table of loaded modules
+pub const LUA_LOADED_TABLE: *const c_char = cstr!("_LOADED");
+
+// Key, in the registry, for table of preloaded loaders
+pub const LUA_PRELOAD_TABLE: *const c_char = cstr!("_PRELOAD");
+
+#[repr(C)]
+pub struct luaL_Reg {
+    pub name: *const c_char,
+    pub func: lua_CFunction,
+}
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua53", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    pub fn luaL_checkversion_(L: *mut lua_State, ver: lua_Number, sz: usize);
+
+    pub fn luaL_getmetafield(L: *mut lua_State, obj: c_int, e: *const c_char) -> c_int;
+    pub fn luaL_callmeta(L: *mut lua_State, obj: c_int, e: *const c_char) -> c_int;
+    #[link_name = "luaL_tolstring"]
+    pub fn luaL_tolstring_(L: *mut lua_State, idx: c_int, len: *mut usize) -> *const c_char;
+    pub fn luaL_argerror(L: *mut lua_State, arg: c_int, extramsg: *const c_char) -> c_int;
+    pub fn luaL_checklstring(L: *mut lua_State, arg: c_int, l: *mut usize) -> *const c_char;
+    pub fn luaL_optlstring(L: *mut lua_State, arg: c_int, def: *const c_char, l: *mut usize)
+        -> *const c_char;
+    pub fn luaL_checknumber(L: *mut lua_State, arg: c_int) -> lua_Number;
+    pub fn luaL_optnumber(L: *mut lua_State, arg: c_int, def: lua_Number) -> lua_Number;
+    pub fn luaL_checkinteger(L: *mut lua_State, arg: c_int) -> lua_Integer;
+    pub fn luaL_optinteger(L: *mut lua_State, arg: c_int, def: lua_Integer) -> lua_Integer;
+
+    pub fn luaL_checkstack(L: *mut lua_State, sz: c_int, msg: *const c_char);
+    pub fn luaL_checktype(L: *mut lua_State, arg: c_int, t: c_int);
+    pub fn luaL_checkany(L: *mut lua_State, arg: c_int);
+
+    pub fn luaL_newmetatable(L: *mut lua_State, tname: *const c_char) -> c_int;
+    pub fn luaL_setmetatable(L: *mut lua_State, tname: *const c_char);
+    pub fn luaL_testudata(L: *mut lua_State, ud: c_int, tname: *const c_char) -> *mut c_void;
+    pub fn luaL_checkudata(L: *mut lua_State, ud: c_int, tname: *const c_char) -> *mut c_void;
+
+    pub fn luaL_where(L: *mut lua_State, lvl: c_int);
+    pub fn luaL_error(L: *mut lua_State, fmt: *const c_char, ...) -> c_int;
+
+    pub fn luaL_checkoption(
+        L: *mut lua_State,
+        arg: c_int,
+        def: *const c_char,
+        lst: *const *const c_char,
+    ) -> c_int;
+
+    pub fn luaL_fileresult(L: *mut lua_State, stat: c_int, fname: *const c_char) -> c_int;
+    pub fn luaL_execresult(L: *mut lua_State, stat: c_int) -> c_int;
+}
+
+// Pre-defined references
+pub const LUA_NOREF: c_int = -2;
+pub const LUA_REFNIL: c_int = -1;
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua53", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    pub fn luaL_ref(L: *mut lua_State, t: c_int) -> c_int;
+    pub fn luaL_unref(L: *mut lua_State, t: c_int, r#ref: c_int);
+
+    pub fn luaL_loadfilex(L: *mut lua_State, filename: *const c_char, mode: *const c_char) -> c_int;
+}
+
+#[inline(always)]
+pub unsafe fn luaL_loadfile(L: *mut lua_State, f: *const c_char) -> c_int {
+    luaL_loadfilex(L, f, ptr::null())
+}
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua53", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    pub fn luaL_loadbufferx(
+        L: *mut lua_State,
+        buff: *const c_char,
+        sz: usize,
+        name: *const c_char,
+        mode: *const c_char,
+    ) -> c_int;
+    pub fn luaL_loadstring(L: *mut lua_State, s: *const c_char) -> c_int;
+
+    pub fn luaL_newstate() -> *mut lua_State;
+
+    pub fn luaL_len(L: *mut lua_State, idx: c_int) -> lua_Integer;
+
+    pub fn luaL_gsub(
+        L: *mut lua_State,
+        s: *const c_char,
+        p: *const c_char,
+        r: *const c_char,
+    ) -> *const c_char;
+
+    pub fn luaL_setfuncs(L: *mut lua_State, l: *const luaL_Reg, nup: c_int);
+
+    pub fn luaL_getsubtable(L: *mut lua_State, idx: c_int, fname: *const c_char) -> c_int;
+
+    pub fn luaL_traceback(L: *mut lua_State, L1: *mut lua_State, msg: *const c_char, level: c_int);
+
+    pub fn luaL_requiref(L: *mut lua_State, modname: *const c_char, openf: lua_CFunction, glb: c_int);
+}
+
+//
+// Some useful macros (implemented as Rust functions)
+//
+
+// TODO: luaL_newlibtable, luaL_newlib
+
+#[inline(always)]
+pub unsafe fn luaL_argcheck(L: *mut lua_State, cond: c_int, arg: c_int, extramsg: *const c_char) {
+    if cond == 0 {
+        luaL_argerror(L, arg, extramsg);
+    }
+}
+
+#[inline(always)]
+pub unsafe fn luaL_checkstring(L: *mut lua_State, n: c_int) -> *const c_char {
+    luaL_checklstring(L, n, ptr::null_mut())
+}
+
+#[inline(always)]
+pub unsafe fn luaL_optstring(L: *mut lua_State, n: c_int, d: *const c_char) -> *const c_char {
+    luaL_optlstring(L, n, d, ptr::null_mut())
+}
+
+#[inline(always)]
+pub unsafe fn luaL_typename(L: *mut lua_State, i: c_int) -> *const c_char {
+    lua::lua_typename(L, lua::lua_type(L, i))
+}
+
+#[inline(always)]
+pub unsafe fn luaL_dofile(L: *mut lua_State, filename: *const c_char) -> c_int {
+    let status = luaL_loadfile(L, filename);
+    if status == 0 {
+        lua::lua_pcall(L, 0, lua::LUA_MULTRET, 0)
+    } else {
+        status
+    }
+}
+
+#[inline(always)]
+pub unsafe fn luaL_dostring(L: *mut lua_State, s: *const c_char) -> c_int {
+    let status = luaL_loadstring(L, s);
+    if status == 0 {
+        lua::lua_pcall(L, 0, lua::LUA_MULTRET, 0)
+    } else {
+        status
+    }
+}
+
+#[inline(always)]
+pub unsafe fn luaL_getmetatable(L: *mut lua_State, n: *const c_char) {
+    lua::lua_getfield(L, lua::LUA_REGISTRYINDEX, n);
+}
+
+#[inline(always)]
+pub unsafe fn luaL_tolstring(L: *mut lua_State, idx: c_int, len: *mut usize) -> *const c_char {
+    luaL_tolstring_(L, lua::lua_absindex(L, idx), len)
+}
+
+// luaL_opt would be implemented here but it is undocumented, so it's omitted
+
+#[inline(always)]
+pub unsafe fn luaL_loadbuffer(L: *mut lua_State, s: *const c_char, sz: usize, n: *const c_char) -> c_int {
+    luaL_loadbufferx(L, s, sz, n, ptr::null())
+}
+
+//
+// TODO: Generic Buffer Manipulation
+//

mlua-sys/src/lua53/lua.rs

@@ -0,0 +1,514 @@
+//! Contains definitions from `lua.h`.
+
+use std::ffi::CStr;
+use std::marker::{PhantomData, PhantomPinned};
+use std::os::raw::{c_char, c_double, c_int, c_uchar, c_void};
+use std::{mem, ptr};
+
+// Mark for precompiled code (`<esc>Lua`)
+pub const LUA_SIGNATURE: &[u8] = b"\x1bLua";
+
+// Option for multiple returns in 'lua_pcall' and 'lua_call'
+pub const LUA_MULTRET: c_int = -1;
+
+// Size of the Lua stack
+pub const LUAI_MAXSTACK: c_int = 1000000;
+
+// Size of a raw memory area associated with  a Lua state with very fast access.
+pub const LUA_EXTRASPACE: usize = mem::size_of::<*const ()>();
+
+//
+// Pseudo-indices
+//
+pub const LUA_REGISTRYINDEX: c_int = -LUAI_MAXSTACK - 1000;
+
+pub const fn lua_upvalueindex(i: c_int) -> c_int {
+    LUA_REGISTRYINDEX - i
+}
+
+//
+// Thread status
+//
+pub const LUA_OK: c_int = 0;
+pub const LUA_YIELD: c_int = 1;
+pub const LUA_ERRRUN: c_int = 2;
+pub const LUA_ERRSYNTAX: c_int = 3;
+pub const LUA_ERRMEM: c_int = 4;
+pub const LUA_ERRGCMM: c_int = 5;
+pub const LUA_ERRERR: c_int = 6;
+
+/// A raw Lua state associated with a thread.
+#[repr(C)]
+pub struct lua_State {
+    _data: [u8; 0],
+    _marker: PhantomData<(*mut u8, PhantomPinned)>,
+}
+
+//
+// Basic types
+//
+pub const LUA_TNONE: c_int = -1;
+
+pub const LUA_TNIL: c_int = 0;
+pub const LUA_TBOOLEAN: c_int = 1;
+pub const LUA_TLIGHTUSERDATA: c_int = 2;
+pub const LUA_TNUMBER: c_int = 3;
+pub const LUA_TSTRING: c_int = 4;
+pub const LUA_TTABLE: c_int = 5;
+pub const LUA_TFUNCTION: c_int = 6;
+pub const LUA_TUSERDATA: c_int = 7;
+pub const LUA_TTHREAD: c_int = 8;
+
+pub const LUA_NUMTAGS: c_int = 9;
+
+/// Minimum Lua stack available to a C function
+pub const LUA_MINSTACK: c_int = 20;
+
+// Predefined values in the registry
+pub const LUA_RIDX_MAINTHREAD: lua_Integer = 1;
+pub const LUA_RIDX_GLOBALS: lua_Integer = 2;
+pub const LUA_RIDX_LAST: lua_Integer = LUA_RIDX_GLOBALS;
+
+/// A Lua number, usually equivalent to `f64`
+pub type lua_Number = c_double;
+
+/// A Lua integer, usually equivalent to `i64`
+pub type lua_Integer = i64;
+
+/// A Lua unsigned integer, usually equivalent to `u64`
+pub type lua_Unsigned = u64;
+
+/// Type for continuation-function contexts
+pub type lua_KContext = isize;
+
+/// Type for native C functions that can be passed to Lua
+pub type lua_CFunction = unsafe extern "C-unwind" fn(L: *mut lua_State) -> c_int;
+
+/// Type for continuation functions
+pub type lua_KFunction =
+    unsafe extern "C-unwind" fn(L: *mut lua_State, status: c_int, ctx: lua_KContext) -> c_int;
+
+// Type for functions that read/write blocks when loading/dumping Lua chunks
+#[rustfmt::skip]
+pub type lua_Reader =
+    unsafe extern "C-unwind" fn(L: *mut lua_State, ud: *mut c_void, sz: *mut usize) -> *const c_char;
+#[rustfmt::skip]
+pub type lua_Writer =
+    unsafe extern "C-unwind" fn(L: *mut lua_State, p: *const c_void, sz: usize, ud: *mut c_void) -> c_int;
+
+/// Type for memory-allocation functions (no unwinding)
+#[rustfmt::skip]
+pub type lua_Alloc =
+    unsafe extern "C" fn(ud: *mut c_void, ptr: *mut c_void, osize: usize, nsize: usize) -> *mut c_void;
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua53", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    //
+    // State manipulation
+    //
+    pub fn lua_newstate(f: lua_Alloc, ud: *mut c_void) -> *mut lua_State;
+    pub fn lua_close(L: *mut lua_State);
+    pub fn lua_newthread(L: *mut lua_State) -> *mut lua_State;
+
+    pub fn lua_atpanic(L: *mut lua_State, panicf: lua_CFunction) -> lua_CFunction;
+
+    pub fn lua_version(L: *mut lua_State) -> *const lua_Number;
+
+    //
+    // Basic stack manipulation
+    //
+    pub fn lua_absindex(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_gettop(L: *mut lua_State) -> c_int;
+    pub fn lua_settop(L: *mut lua_State, idx: c_int);
+    pub fn lua_pushvalue(L: *mut lua_State, idx: c_int);
+    pub fn lua_rotate(L: *mut lua_State, idx: c_int, n: c_int);
+    pub fn lua_copy(L: *mut lua_State, fromidx: c_int, toidx: c_int);
+    pub fn lua_checkstack(L: *mut lua_State, sz: c_int) -> c_int;
+
+    pub fn lua_xmove(from: *mut lua_State, to: *mut lua_State, n: c_int);
+
+    //
+    // Access functions (stack -> C)
+    //
+    pub fn lua_isnumber(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_isstring(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_iscfunction(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_isinteger(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_isuserdata(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_type(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_typename(L: *mut lua_State, tp: c_int) -> *const c_char;
+
+    pub fn lua_tonumberx(L: *mut lua_State, idx: c_int, isnum: *mut c_int) -> lua_Number;
+    pub fn lua_tointegerx(L: *mut lua_State, idx: c_int, isnum: *mut c_int) -> lua_Integer;
+    pub fn lua_toboolean(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_tolstring(L: *mut lua_State, idx: c_int, len: *mut usize) -> *const c_char;
+    pub fn lua_rawlen(L: *mut lua_State, idx: c_int) -> usize;
+    pub fn lua_tocfunction(L: *mut lua_State, idx: c_int) -> Option<lua_CFunction>;
+    pub fn lua_touserdata(L: *mut lua_State, idx: c_int) -> *mut c_void;
+    pub fn lua_tothread(L: *mut lua_State, idx: c_int) -> *mut lua_State;
+    pub fn lua_topointer(L: *mut lua_State, idx: c_int) -> *const c_void;
+}
+
+//
+// Comparison and arithmetic functions
+//
+pub const LUA_OPADD: c_int = 0;
+pub const LUA_OPSUB: c_int = 1;
+pub const LUA_OPMUL: c_int = 2;
+pub const LUA_OPMOD: c_int = 3;
+pub const LUA_OPPOW: c_int = 4;
+pub const LUA_OPDIV: c_int = 5;
+pub const LUA_OPIDIV: c_int = 6;
+pub const LUA_OPBAND: c_int = 7;
+pub const LUA_OPBOR: c_int = 8;
+pub const LUA_OPBXOR: c_int = 9;
+pub const LUA_OPSHL: c_int = 10;
+pub const LUA_OPSHR: c_int = 11;
+pub const LUA_OPUNM: c_int = 12;
+pub const LUA_OPBNOT: c_int = 13;
+
+pub const LUA_OPEQ: c_int = 0;
+pub const LUA_OPLT: c_int = 1;
+pub const LUA_OPLE: c_int = 2;
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua53", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    pub fn lua_arith(L: *mut lua_State, op: c_int);
+    pub fn lua_rawequal(L: *mut lua_State, idx1: c_int, idx2: c_int) -> c_int;
+    pub fn lua_compare(L: *mut lua_State, idx1: c_int, idx2: c_int, op: c_int) -> c_int;
+}
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua53", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    //
+    // Push functions (C -> stack)
+    //
+    pub fn lua_pushnil(L: *mut lua_State);
+    pub fn lua_pushnumber(L: *mut lua_State, n: lua_Number);
+    pub fn lua_pushinteger(L: *mut lua_State, n: lua_Integer);
+    pub fn lua_pushlstring(L: *mut lua_State, s: *const c_char, len: usize) -> *const c_char;
+    pub fn lua_pushstring(L: *mut lua_State, s: *const c_char) -> *const c_char;
+    // lua_pushvfstring
+    pub fn lua_pushfstring(L: *mut lua_State, fmt: *const c_char, ...) -> *const c_char;
+    pub fn lua_pushcclosure(L: *mut lua_State, f: lua_CFunction, n: c_int);
+    pub fn lua_pushboolean(L: *mut lua_State, b: c_int);
+    pub fn lua_pushlightuserdata(L: *mut lua_State, p: *mut c_void);
+    pub fn lua_pushthread(L: *mut lua_State) -> c_int;
+
+    //
+    // Get functions (Lua -> stack)
+    //
+    pub fn lua_getglobal(L: *mut lua_State, name: *const c_char) -> c_int;
+    pub fn lua_gettable(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_getfield(L: *mut lua_State, idx: c_int, k: *const c_char) -> c_int;
+    pub fn lua_geti(L: *mut lua_State, idx: c_int, n: lua_Integer) -> c_int;
+    pub fn lua_rawget(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_rawgeti(L: *mut lua_State, idx: c_int, n: lua_Integer) -> c_int;
+    pub fn lua_rawgetp(L: *mut lua_State, idx: c_int, p: *const c_void) -> c_int;
+
+    pub fn lua_createtable(L: *mut lua_State, narr: c_int, nrec: c_int);
+    pub fn lua_newuserdata(L: *mut lua_State, sz: usize) -> *mut c_void;
+    pub fn lua_getmetatable(L: *mut lua_State, objindex: c_int) -> c_int;
+    pub fn lua_getuservalue(L: *mut lua_State, idx: c_int) -> c_int;
+
+    //
+    // Set functions (stack -> Lua)
+    //
+    pub fn lua_setglobal(L: *mut lua_State, name: *const c_char);
+    pub fn lua_settable(L: *mut lua_State, idx: c_int);
+    pub fn lua_setfield(L: *mut lua_State, idx: c_int, k: *const c_char);
+    pub fn lua_seti(L: *mut lua_State, idx: c_int, n: lua_Integer);
+    pub fn lua_rawset(L: *mut lua_State, idx: c_int);
+    pub fn lua_rawseti(L: *mut lua_State, idx: c_int, n: lua_Integer);
+    pub fn lua_rawsetp(L: *mut lua_State, idx: c_int, p: *const c_void);
+    pub fn lua_setmetatable(L: *mut lua_State, objindex: c_int) -> c_int;
+    pub fn lua_setuservalue(L: *mut lua_State, idx: c_int);
+
+    //
+    // 'load' and 'call' functions (load and run Lua code)
+    //
+    pub fn lua_callk(
+        L: *mut lua_State,
+        nargs: c_int,
+        nresults: c_int,
+        ctx: lua_KContext,
+        k: Option<lua_KFunction>,
+    );
+    pub fn lua_pcallk(
+        L: *mut lua_State,
+        nargs: c_int,
+        nresults: c_int,
+        errfunc: c_int,
+        ctx: lua_KContext,
+        k: Option<lua_KFunction>,
+    ) -> c_int;
+
+    pub fn lua_load(
+        L: *mut lua_State,
+        reader: lua_Reader,
+        data: *mut c_void,
+        chunkname: *const c_char,
+        mode: *const c_char,
+    ) -> c_int;
+
+    pub fn lua_dump(L: *mut lua_State, writer: lua_Writer, data: *mut c_void, strip: c_int) -> c_int;
+}
+
+#[inline(always)]
+pub unsafe fn lua_call(L: *mut lua_State, n: c_int, r: c_int) {
+    lua_callk(L, n, r, 0, None)
+}
+
+#[inline(always)]
+pub unsafe fn lua_pcall(L: *mut lua_State, n: c_int, r: c_int, f: c_int) -> c_int {
+    lua_pcallk(L, n, r, f, 0, None)
+}
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua53", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    //
+    // Coroutine functions
+    //
+    pub fn lua_yieldk(
+        L: *mut lua_State,
+        nresults: c_int,
+        ctx: lua_KContext,
+        k: Option<lua_KFunction>,
+    ) -> c_int;
+    #[link_name = "lua_resume"]
+    pub fn lua_resume_(L: *mut lua_State, from: *mut lua_State, narg: c_int) -> c_int;
+    pub fn lua_status(L: *mut lua_State) -> c_int;
+    pub fn lua_isyieldable(L: *mut lua_State) -> c_int;
+}
+
+#[inline(always)]
+pub unsafe fn lua_yield(L: *mut lua_State, n: c_int) -> c_int {
+    lua_yieldk(L, n, 0, None)
+}
+
+//
+// Garbage-collection function and options
+//
+pub const LUA_GCSTOP: c_int = 0;
+pub const LUA_GCRESTART: c_int = 1;
+pub const LUA_GCCOLLECT: c_int = 2;
+pub const LUA_GCCOUNT: c_int = 3;
+pub const LUA_GCCOUNTB: c_int = 4;
+pub const LUA_GCSTEP: c_int = 5;
+pub const LUA_GCSETPAUSE: c_int = 6;
+pub const LUA_GCSETSTEPMUL: c_int = 7;
+pub const LUA_GCISRUNNING: c_int = 9;
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua53", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    pub fn lua_gc(L: *mut lua_State, what: c_int, data: c_int) -> c_int;
+}
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua53", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    //
+    // Miscellaneous functions
+    //
+    #[link_name = "lua_error"]
+    fn lua_error_(L: *mut lua_State) -> c_int;
+    pub fn lua_next(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_concat(L: *mut lua_State, n: c_int);
+    pub fn lua_len(L: *mut lua_State, idx: c_int);
+    pub fn lua_stringtonumber(L: *mut lua_State, s: *const c_char) -> usize;
+    pub fn lua_getallocf(L: *mut lua_State, ud: *mut *mut c_void) -> lua_Alloc;
+    pub fn lua_setallocf(L: *mut lua_State, f: lua_Alloc, ud: *mut c_void);
+}
+
+// lua_error does not return but is declared to return int, and Rust translates
+// ! to void which can cause link-time errors if the platform linker is aware
+// of return types and requires they match (for example: wasm does this).
+#[inline(always)]
+pub unsafe fn lua_error(L: *mut lua_State) -> ! {
+    lua_error_(L);
+    unreachable!();
+}
+
+//
+// Some useful macros (implemented as Rust functions)
+//
+#[inline(always)]
+pub unsafe fn lua_getextraspace(L: *mut lua_State) -> *mut c_void {
+    (L as *mut c_char).sub(LUA_EXTRASPACE) as *mut c_void
+}
+
+#[inline(always)]
+pub unsafe fn lua_tonumber(L: *mut lua_State, i: c_int) -> lua_Number {
+    lua_tonumberx(L, i, ptr::null_mut())
+}
+
+#[inline(always)]
+pub unsafe fn lua_tointeger(L: *mut lua_State, i: c_int) -> lua_Integer {
+    lua_tointegerx(L, i, ptr::null_mut())
+}
+
+#[inline(always)]
+pub unsafe fn lua_pop(L: *mut lua_State, n: c_int) {
+    lua_settop(L, -n - 1)
+}
+
+#[inline(always)]
+pub unsafe fn lua_newtable(L: *mut lua_State) {
+    lua_createtable(L, 0, 0)
+}
+
+#[inline(always)]
+pub unsafe fn lua_register(L: *mut lua_State, n: *const c_char, f: lua_CFunction) {
+    lua_pushcfunction(L, f);
+    lua_setglobal(L, n)
+}
+
+#[inline(always)]
+pub unsafe fn lua_pushcfunction(L: *mut lua_State, f: lua_CFunction) {
+    lua_pushcclosure(L, f, 0)
+}
+
+#[inline(always)]
+pub unsafe fn lua_isfunction(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TFUNCTION) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_istable(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TTABLE) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_islightuserdata(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TLIGHTUSERDATA) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_isnil(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TNIL) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_isboolean(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TBOOLEAN) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_isthread(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TTHREAD) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_isnone(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TNONE) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_isnoneornil(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) <= 0) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_pushliteral(L: *mut lua_State, s: &'static CStr) {
+    lua_pushstring(L, s.as_ptr());
+}
+
+#[inline(always)]
+pub unsafe fn lua_pushglobaltable(L: *mut lua_State) -> c_int {
+    lua_rawgeti(L, LUA_REGISTRYINDEX, LUA_RIDX_GLOBALS)
+}
+
+#[inline(always)]
+pub unsafe fn lua_tolightuserdata(L: *mut lua_State, idx: c_int) -> *mut c_void {
+    if lua_islightuserdata(L, idx) != 0 {
+        return lua_touserdata(L, idx);
+    }
+    ptr::null_mut()
+}
+
+#[inline(always)]
+pub unsafe fn lua_tostring(L: *mut lua_State, i: c_int) -> *const c_char {
+    lua_tolstring(L, i, ptr::null_mut())
+}
+
+#[inline(always)]
+pub unsafe fn lua_insert(L: *mut lua_State, idx: c_int) {
+    lua_rotate(L, idx, 1)
+}
+
+#[inline(always)]
+pub unsafe fn lua_remove(L: *mut lua_State, idx: c_int) {
+    lua_rotate(L, idx, -1);
+    lua_pop(L, 1)
+}
+
+#[inline(always)]
+pub unsafe fn lua_replace(L: *mut lua_State, idx: c_int) {
+    lua_copy(L, -1, idx);
+    lua_pop(L, 1)
+}
+
+#[inline(always)]
+pub unsafe fn lua_xpush(from: *mut lua_State, to: *mut lua_State, idx: c_int) {
+    lua_pushvalue(from, idx);
+    lua_xmove(from, to, 1);
+}
+
+//
+// Debug API
+//
+
+// Maximum size for the description of the source of a function in debug information.
+const LUA_IDSIZE: usize = 60;
+
+// Event codes
+pub const LUA_HOOKCALL: c_int = 0;
+pub const LUA_HOOKRET: c_int = 1;
+pub const LUA_HOOKLINE: c_int = 2;
+pub const LUA_HOOKCOUNT: c_int = 3;
+pub const LUA_HOOKTAILCALL: c_int = 4;
+
+// Event masks
+pub const LUA_MASKCALL: c_int = 1 << (LUA_HOOKCALL as usize);
+pub const LUA_MASKRET: c_int = 1 << (LUA_HOOKRET as usize);
+pub const LUA_MASKLINE: c_int = 1 << (LUA_HOOKLINE as usize);
+pub const LUA_MASKCOUNT: c_int = 1 << (LUA_HOOKCOUNT as usize);
+
+/// Type for functions to be called on debug events.
+pub type lua_Hook = unsafe extern "C-unwind" fn(L: *mut lua_State, ar: *mut lua_Debug);
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua53", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    pub fn lua_getstack(L: *mut lua_State, level: c_int, ar: *mut lua_Debug) -> c_int;
+    pub fn lua_getinfo(L: *mut lua_State, what: *const c_char, ar: *mut lua_Debug) -> c_int;
+    pub fn lua_getlocal(L: *mut lua_State, ar: *const lua_Debug, n: c_int) -> *const c_char;
+    pub fn lua_setlocal(L: *mut lua_State, ar: *const lua_Debug, n: c_int) -> *const c_char;
+    pub fn lua_getupvalue(L: *mut lua_State, funcindex: c_int, n: c_int) -> *const c_char;
+    pub fn lua_setupvalue(L: *mut lua_State, funcindex: c_int, n: c_int) -> *const c_char;
+
+    pub fn lua_upvalueid(L: *mut lua_State, fidx: c_int, n: c_int) -> *mut c_void;
+    pub fn lua_upvaluejoin(L: *mut lua_State, fidx1: c_int, n1: c_int, fidx2: c_int, n2: c_int);
+
+    pub fn lua_sethook(L: *mut lua_State, func: Option<lua_Hook>, mask: c_int, count: c_int);
+    pub fn lua_gethook(L: *mut lua_State) -> Option<lua_Hook>;
+    pub fn lua_gethookmask(L: *mut lua_State) -> c_int;
+    pub fn lua_gethookcount(L: *mut lua_State) -> c_int;
+}
+
+#[repr(C)]
+pub struct lua_Debug {
+    pub event: c_int,
+    pub name: *const c_char,
+    pub namewhat: *const c_char,
+    pub what: *const c_char,
+    pub source: *const c_char,
+    pub currentline: c_int,
+    pub linedefined: c_int,
+    pub lastlinedefined: c_int,
+    pub nups: c_uchar,
+    pub nparams: c_uchar,
+    pub isvararg: c_char,
+    pub istailcall: c_char,
+    pub short_src: [c_char; LUA_IDSIZE],
+    // lua.h mentions this is for private use
+    i_ci: *mut c_void,
+}

mlua-sys/src/lua53/lualib.rs

@@ -0,0 +1,34 @@
+//! Contains definitions from `lualib.h`.
+
+use std::os::raw::{c_char, c_int};
+
+use super::lua::lua_State;
+
+pub const LUA_COLIBNAME: *const c_char = cstr!("coroutine");
+pub const LUA_TABLIBNAME: *const c_char = cstr!("table");
+pub const LUA_IOLIBNAME: *const c_char = cstr!("io");
+pub const LUA_OSLIBNAME: *const c_char = cstr!("os");
+pub const LUA_STRLIBNAME: *const c_char = cstr!("string");
+pub const LUA_UTF8LIBNAME: *const c_char = cstr!("utf8");
+pub const LUA_BITLIBNAME: *const c_char = cstr!("bit32");
+pub const LUA_MATHLIBNAME: *const c_char = cstr!("math");
+pub const LUA_DBLIBNAME: *const c_char = cstr!("debug");
+pub const LUA_LOADLIBNAME: *const c_char = cstr!("package");
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua53", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    pub fn luaopen_base(L: *mut lua_State) -> c_int;
+    pub fn luaopen_coroutine(L: *mut lua_State) -> c_int;
+    pub fn luaopen_table(L: *mut lua_State) -> c_int;
+    pub fn luaopen_io(L: *mut lua_State) -> c_int;
+    pub fn luaopen_os(L: *mut lua_State) -> c_int;
+    pub fn luaopen_string(L: *mut lua_State) -> c_int;
+    pub fn luaopen_utf8(L: *mut lua_State) -> c_int;
+    pub fn luaopen_bit32(L: *mut lua_State) -> c_int;
+    pub fn luaopen_math(L: *mut lua_State) -> c_int;
+    pub fn luaopen_debug(L: *mut lua_State) -> c_int;
+    pub fn luaopen_package(L: *mut lua_State) -> c_int;
+
+    // open all builtin libraries
+    pub fn luaL_openlibs(L: *mut lua_State);
+}

mlua-sys/src/lua53/mod.rs

@@ -0,0 +1,11 @@
+//! Low level bindings to Lua 5.3.
+
+pub use compat::*;
+pub use lauxlib::*;
+pub use lua::*;
+pub use lualib::*;
+
+pub mod compat;
+pub mod lauxlib;
+pub mod lua;
+pub mod lualib;

mlua-sys/src/lua54/lauxlib.rs

@@ -0,0 +1,193 @@
+//! Contains definitions from `lauxlib.h`.
+
+use std::os::raw::{c_char, c_int, c_void};
+use std::ptr;
+
+use super::lua::{self, lua_CFunction, lua_Integer, lua_Number, lua_State};
+
+// Extra error code for 'luaL_loadfilex'
+pub const LUA_ERRFILE: c_int = lua::LUA_ERRERR + 1;
+
+// Key, in the registry, for table of loaded modules
+pub const LUA_LOADED_TABLE: *const c_char = cstr!("_LOADED");
+
+// Key, in the registry, for table of preloaded loaders
+pub const LUA_PRELOAD_TABLE: *const c_char = cstr!("_PRELOAD");
+
+#[repr(C)]
+pub struct luaL_Reg {
+    pub name: *const c_char,
+    pub func: lua_CFunction,
+}
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua54", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    pub fn luaL_checkversion_(L: *mut lua_State, ver: lua_Number, sz: usize);
+
+    pub fn luaL_getmetafield(L: *mut lua_State, obj: c_int, e: *const c_char) -> c_int;
+    pub fn luaL_callmeta(L: *mut lua_State, obj: c_int, e: *const c_char) -> c_int;
+    pub fn luaL_tolstring(L: *mut lua_State, idx: c_int, len: *mut usize) -> *const c_char;
+    pub fn luaL_argerror(L: *mut lua_State, arg: c_int, extramsg: *const c_char) -> c_int;
+    pub fn luaL_checklstring(L: *mut lua_State, arg: c_int, l: *mut usize) -> *const c_char;
+    pub fn luaL_optlstring(L: *mut lua_State, arg: c_int, def: *const c_char, l: *mut usize)
+        -> *const c_char;
+    pub fn luaL_checknumber(L: *mut lua_State, arg: c_int) -> lua_Number;
+    pub fn luaL_optnumber(L: *mut lua_State, arg: c_int, def: lua_Number) -> lua_Number;
+    pub fn luaL_checkinteger(L: *mut lua_State, arg: c_int) -> lua_Integer;
+    pub fn luaL_optinteger(L: *mut lua_State, arg: c_int, def: lua_Integer) -> lua_Integer;
+
+    pub fn luaL_checkstack(L: *mut lua_State, sz: c_int, msg: *const c_char);
+    pub fn luaL_checktype(L: *mut lua_State, arg: c_int, t: c_int);
+    pub fn luaL_checkany(L: *mut lua_State, arg: c_int);
+
+    pub fn luaL_newmetatable(L: *mut lua_State, tname: *const c_char) -> c_int;
+    pub fn luaL_setmetatable(L: *mut lua_State, tname: *const c_char);
+    pub fn luaL_testudata(L: *mut lua_State, ud: c_int, tname: *const c_char) -> *mut c_void;
+    pub fn luaL_checkudata(L: *mut lua_State, ud: c_int, tname: *const c_char) -> *mut c_void;
+
+    pub fn luaL_where(L: *mut lua_State, lvl: c_int);
+    pub fn luaL_error(L: *mut lua_State, fmt: *const c_char, ...) -> c_int;
+
+    pub fn luaL_checkoption(
+        L: *mut lua_State,
+        arg: c_int,
+        def: *const c_char,
+        lst: *const *const c_char,
+    ) -> c_int;
+
+    pub fn luaL_fileresult(L: *mut lua_State, stat: c_int, fname: *const c_char) -> c_int;
+    pub fn luaL_execresult(L: *mut lua_State, stat: c_int) -> c_int;
+}
+
+// Pre-defined references
+pub const LUA_NOREF: c_int = -2;
+pub const LUA_REFNIL: c_int = -1;
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua54", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    pub fn luaL_ref(L: *mut lua_State, t: c_int) -> c_int;
+    pub fn luaL_unref(L: *mut lua_State, t: c_int, r#ref: c_int);
+
+    pub fn luaL_loadfilex(L: *mut lua_State, filename: *const c_char, mode: *const c_char) -> c_int;
+}
+
+#[inline(always)]
+pub unsafe fn luaL_loadfile(L: *mut lua_State, f: *const c_char) -> c_int {
+    luaL_loadfilex(L, f, ptr::null())
+}
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua54", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    pub fn luaL_loadbufferx(
+        L: *mut lua_State,
+        buff: *const c_char,
+        sz: usize,
+        name: *const c_char,
+        mode: *const c_char,
+    ) -> c_int;
+    pub fn luaL_loadstring(L: *mut lua_State, s: *const c_char) -> c_int;
+
+    pub fn luaL_newstate() -> *mut lua_State;
+
+    pub fn luaL_len(L: *mut lua_State, idx: c_int) -> lua_Integer;
+
+    // TODO: luaL_addgsub
+
+    pub fn luaL_gsub(
+        L: *mut lua_State,
+        s: *const c_char,
+        p: *const c_char,
+        r: *const c_char,
+    ) -> *const c_char;
+
+    pub fn luaL_setfuncs(L: *mut lua_State, l: *const luaL_Reg, nup: c_int);
+
+    pub fn luaL_getsubtable(L: *mut lua_State, idx: c_int, fname: *const c_char) -> c_int;
+
+    pub fn luaL_traceback(L: *mut lua_State, L1: *mut lua_State, msg: *const c_char, level: c_int);
+
+    pub fn luaL_requiref(L: *mut lua_State, modname: *const c_char, openf: lua_CFunction, glb: c_int);
+}
+
+//
+// Some useful macros (implemented as Rust functions)
+//
+
+// TODO: luaL_newlibtable, luaL_newlib
+
+#[inline(always)]
+pub unsafe fn luaL_argcheck(L: *mut lua_State, cond: c_int, arg: c_int, extramsg: *const c_char) {
+    if cond == 0 {
+        luaL_argerror(L, arg, extramsg);
+    }
+}
+
+#[inline(always)]
+pub unsafe fn luaL_checkstring(L: *mut lua_State, n: c_int) -> *const c_char {
+    luaL_checklstring(L, n, ptr::null_mut())
+}
+
+#[inline(always)]
+pub unsafe fn luaL_optstring(L: *mut lua_State, n: c_int, d: *const c_char) -> *const c_char {
+    luaL_optlstring(L, n, d, ptr::null_mut())
+}
+
+#[inline(always)]
+pub unsafe fn luaL_typename(L: *mut lua_State, i: c_int) -> *const c_char {
+    lua::lua_typename(L, lua::lua_type(L, i))
+}
+
+#[inline(always)]
+pub unsafe fn luaL_dofile(L: *mut lua_State, filename: *const c_char) -> c_int {
+    let status = luaL_loadfile(L, filename);
+    if status == 0 {
+        lua::lua_pcall(L, 0, lua::LUA_MULTRET, 0)
+    } else {
+        status
+    }
+}
+
+#[inline(always)]
+pub unsafe fn luaL_dostring(L: *mut lua_State, s: *const c_char) -> c_int {
+    let status = luaL_loadstring(L, s);
+    if status == 0 {
+        lua::lua_pcall(L, 0, lua::LUA_MULTRET, 0)
+    } else {
+        status
+    }
+}
+
+#[inline(always)]
+pub unsafe fn luaL_getmetatable(L: *mut lua_State, n: *const c_char) {
+    lua::lua_getfield(L, lua::LUA_REGISTRYINDEX, n);
+}
+
+// luaL_opt would be implemented here but it is undocumented, so it's omitted
+
+#[inline(always)]
+pub unsafe fn luaL_loadbuffer(L: *mut lua_State, s: *const c_char, sz: usize, n: *const c_char) -> c_int {
+    luaL_loadbufferx(L, s, sz, n, ptr::null())
+}
+
+pub unsafe fn luaL_loadbufferenv(
+    L: *mut lua_State,
+    data: *const c_char,
+    size: usize,
+    name: *const c_char,
+    mode: *const c_char,
+    mut env: c_int,
+) -> c_int {
+    if env != 0 {
+        env = lua::lua_absindex(L, env);
+    }
+    let status = luaL_loadbufferx(L, data, size, name, mode);
+    if status == lua::LUA_OK && env != 0 {
+        lua::lua_pushvalue(L, env);
+        lua::lua_setupvalue(L, -2, 1);
+    }
+    status
+}
+
+//
+// TODO: Generic Buffer Manipulation
+//

mlua-sys/src/lua54/lua.rs

@@ -0,0 +1,559 @@
+//! Contains definitions from `lua.h`.
+
+use std::ffi::CStr;
+use std::marker::{PhantomData, PhantomPinned};
+use std::os::raw::{c_char, c_double, c_int, c_uchar, c_ushort, c_void};
+use std::{mem, ptr};
+
+// Mark for precompiled code (`<esc>Lua`)
+pub const LUA_SIGNATURE: &[u8] = b"\x1bLua";
+
+// Option for multiple returns in 'lua_pcall' and 'lua_call'
+pub const LUA_MULTRET: c_int = -1;
+
+// Size of the Lua stack
+pub const LUAI_MAXSTACK: c_int = 1000000;
+
+// Size of a raw memory area associated with  a Lua state with very fast access.
+pub const LUA_EXTRASPACE: usize = mem::size_of::<*const ()>();
+
+//
+// Pseudo-indices
+//
+pub const LUA_REGISTRYINDEX: c_int = -LUAI_MAXSTACK - 1000;
+
+pub const fn lua_upvalueindex(i: c_int) -> c_int {
+    LUA_REGISTRYINDEX - i
+}
+
+//
+// Thread status
+//
+pub const LUA_OK: c_int = 0;
+pub const LUA_YIELD: c_int = 1;
+pub const LUA_ERRRUN: c_int = 2;
+pub const LUA_ERRSYNTAX: c_int = 3;
+pub const LUA_ERRMEM: c_int = 4;
+pub const LUA_ERRERR: c_int = 5;
+
+/// A raw Lua state associated with a thread.
+#[repr(C)]
+pub struct lua_State {
+    _data: [u8; 0],
+    _marker: PhantomData<(*mut u8, PhantomPinned)>,
+}
+
+//
+// Basic types
+//
+pub const LUA_TNONE: c_int = -1;
+
+pub const LUA_TNIL: c_int = 0;
+pub const LUA_TBOOLEAN: c_int = 1;
+pub const LUA_TLIGHTUSERDATA: c_int = 2;
+pub const LUA_TNUMBER: c_int = 3;
+pub const LUA_TSTRING: c_int = 4;
+pub const LUA_TTABLE: c_int = 5;
+pub const LUA_TFUNCTION: c_int = 6;
+pub const LUA_TUSERDATA: c_int = 7;
+pub const LUA_TTHREAD: c_int = 8;
+
+pub const LUA_NUMTYPES: c_int = 9;
+
+/// Minimum Lua stack available to a C function
+pub const LUA_MINSTACK: c_int = 20;
+
+// Predefined values in the registry
+pub const LUA_RIDX_MAINTHREAD: lua_Integer = 1;
+pub const LUA_RIDX_GLOBALS: lua_Integer = 2;
+pub const LUA_RIDX_LAST: lua_Integer = LUA_RIDX_GLOBALS;
+
+/// A Lua number, usually equivalent to `f64`
+pub type lua_Number = c_double;
+
+/// A Lua integer, usually equivalent to `i64`
+pub type lua_Integer = i64;
+
+/// A Lua unsigned integer, usually equivalent to `u64`
+pub type lua_Unsigned = u64;
+
+/// Type for continuation-function contexts
+pub type lua_KContext = isize;
+
+/// Type for native C functions that can be passed to Lua
+pub type lua_CFunction = unsafe extern "C-unwind" fn(L: *mut lua_State) -> c_int;
+
+/// Type for continuation functions
+pub type lua_KFunction =
+    unsafe extern "C-unwind" fn(L: *mut lua_State, status: c_int, ctx: lua_KContext) -> c_int;
+
+// Type for functions that read/write blocks when loading/dumping Lua chunks
+#[rustfmt::skip]
+pub type lua_Reader =
+    unsafe extern "C-unwind" fn(L: *mut lua_State, ud: *mut c_void, sz: *mut usize) -> *const c_char;
+#[rustfmt::skip]
+pub type lua_Writer =
+    unsafe extern "C-unwind" fn(L: *mut lua_State, p: *const c_void, sz: usize, ud: *mut c_void) -> c_int;
+
+/// Type for memory-allocation functions (no unwinding)
+#[rustfmt::skip]
+pub type lua_Alloc =
+    unsafe extern "C" fn(ud: *mut c_void, ptr: *mut c_void, osize: usize, nsize: usize) -> *mut c_void;
+
+/// Type for warning functions
+pub type lua_WarnFunction = unsafe extern "C-unwind" fn(ud: *mut c_void, msg: *const c_char, tocont: c_int);
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua54", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    //
+    // State manipulation
+    //
+    pub fn lua_newstate(f: lua_Alloc, ud: *mut c_void) -> *mut lua_State;
+    pub fn lua_close(L: *mut lua_State);
+    pub fn lua_newthread(L: *mut lua_State) -> *mut lua_State;
+    // Deprecated in Lua 5.4.6
+    pub fn lua_resetthread(L: *mut lua_State) -> c_int;
+    #[cfg(feature = "vendored")]
+    pub fn lua_closethread(L: *mut lua_State, from: *mut lua_State) -> c_int;
+
+    pub fn lua_atpanic(L: *mut lua_State, panicf: lua_CFunction) -> lua_CFunction;
+
+    pub fn lua_version(L: *mut lua_State) -> lua_Number;
+
+    //
+    // Basic stack manipulation
+    //
+    pub fn lua_absindex(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_gettop(L: *mut lua_State) -> c_int;
+    pub fn lua_settop(L: *mut lua_State, idx: c_int);
+    pub fn lua_pushvalue(L: *mut lua_State, idx: c_int);
+    pub fn lua_rotate(L: *mut lua_State, idx: c_int, n: c_int);
+    pub fn lua_copy(L: *mut lua_State, fromidx: c_int, toidx: c_int);
+    pub fn lua_checkstack(L: *mut lua_State, sz: c_int) -> c_int;
+
+    pub fn lua_xmove(from: *mut lua_State, to: *mut lua_State, n: c_int);
+
+    //
+    // Access functions (stack -> C)
+    //
+    pub fn lua_isnumber(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_isstring(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_iscfunction(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_isinteger(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_isuserdata(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_type(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_typename(L: *mut lua_State, tp: c_int) -> *const c_char;
+
+    pub fn lua_tonumberx(L: *mut lua_State, idx: c_int, isnum: *mut c_int) -> lua_Number;
+    pub fn lua_tointegerx(L: *mut lua_State, idx: c_int, isnum: *mut c_int) -> lua_Integer;
+    pub fn lua_toboolean(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_tolstring(L: *mut lua_State, idx: c_int, len: *mut usize) -> *const c_char;
+    #[link_name = "lua_rawlen"]
+    fn lua_rawlen_(L: *mut lua_State, idx: c_int) -> lua_Unsigned;
+    pub fn lua_tocfunction(L: *mut lua_State, idx: c_int) -> Option<lua_CFunction>;
+    pub fn lua_touserdata(L: *mut lua_State, idx: c_int) -> *mut c_void;
+    pub fn lua_tothread(L: *mut lua_State, idx: c_int) -> *mut lua_State;
+    pub fn lua_topointer(L: *mut lua_State, idx: c_int) -> *const c_void;
+}
+
+// lua_rawlen's return type changed from size_t to lua_Unsigned int in Lua 5.4.
+// This adapts the crate API to the new Lua ABI.
+#[inline(always)]
+pub unsafe fn lua_rawlen(L: *mut lua_State, idx: c_int) -> usize {
+    lua_rawlen_(L, idx) as usize
+}
+
+//
+// Comparison and arithmetic functions
+//
+pub const LUA_OPADD: c_int = 0;
+pub const LUA_OPSUB: c_int = 1;
+pub const LUA_OPMUL: c_int = 2;
+pub const LUA_OPMOD: c_int = 3;
+pub const LUA_OPPOW: c_int = 4;
+pub const LUA_OPDIV: c_int = 5;
+pub const LUA_OPIDIV: c_int = 6;
+pub const LUA_OPBAND: c_int = 7;
+pub const LUA_OPBOR: c_int = 8;
+pub const LUA_OPBXOR: c_int = 9;
+pub const LUA_OPSHL: c_int = 10;
+pub const LUA_OPSHR: c_int = 11;
+pub const LUA_OPUNM: c_int = 12;
+pub const LUA_OPBNOT: c_int = 13;
+
+pub const LUA_OPEQ: c_int = 0;
+pub const LUA_OPLT: c_int = 1;
+pub const LUA_OPLE: c_int = 2;
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua54", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    pub fn lua_arith(L: *mut lua_State, op: c_int);
+    pub fn lua_rawequal(L: *mut lua_State, idx1: c_int, idx2: c_int) -> c_int;
+    pub fn lua_compare(L: *mut lua_State, idx1: c_int, idx2: c_int, op: c_int) -> c_int;
+}
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua54", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    //
+    // Push functions (C -> stack)
+    //
+    pub fn lua_pushnil(L: *mut lua_State);
+    pub fn lua_pushnumber(L: *mut lua_State, n: lua_Number);
+    pub fn lua_pushinteger(L: *mut lua_State, n: lua_Integer);
+    pub fn lua_pushlstring(L: *mut lua_State, s: *const c_char, len: usize) -> *const c_char;
+    pub fn lua_pushstring(L: *mut lua_State, s: *const c_char) -> *const c_char;
+    // lua_pushvfstring
+    pub fn lua_pushfstring(L: *mut lua_State, fmt: *const c_char, ...) -> *const c_char;
+    pub fn lua_pushcclosure(L: *mut lua_State, f: lua_CFunction, n: c_int);
+    pub fn lua_pushboolean(L: *mut lua_State, b: c_int);
+    pub fn lua_pushlightuserdata(L: *mut lua_State, p: *mut c_void);
+    pub fn lua_pushthread(L: *mut lua_State) -> c_int;
+
+    //
+    // Get functions (Lua -> stack)
+    //
+    pub fn lua_getglobal(L: *mut lua_State, name: *const c_char) -> c_int;
+    pub fn lua_gettable(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_getfield(L: *mut lua_State, idx: c_int, k: *const c_char) -> c_int;
+    pub fn lua_geti(L: *mut lua_State, idx: c_int, n: lua_Integer) -> c_int;
+    pub fn lua_rawget(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_rawgeti(L: *mut lua_State, idx: c_int, n: lua_Integer) -> c_int;
+    pub fn lua_rawgetp(L: *mut lua_State, idx: c_int, p: *const c_void) -> c_int;
+
+    pub fn lua_createtable(L: *mut lua_State, narr: c_int, nrec: c_int);
+    pub fn lua_newuserdatauv(L: *mut lua_State, sz: usize, nuvalue: c_int) -> *mut c_void;
+    pub fn lua_getmetatable(L: *mut lua_State, objindex: c_int) -> c_int;
+    pub fn lua_getiuservalue(L: *mut lua_State, idx: c_int, n: c_int) -> c_int;
+
+    //
+    // Set functions (stack -> Lua)
+    //
+    pub fn lua_setglobal(L: *mut lua_State, name: *const c_char);
+    pub fn lua_settable(L: *mut lua_State, idx: c_int);
+    pub fn lua_setfield(L: *mut lua_State, idx: c_int, k: *const c_char);
+    pub fn lua_seti(L: *mut lua_State, idx: c_int, n: lua_Integer);
+    pub fn lua_rawset(L: *mut lua_State, idx: c_int);
+    pub fn lua_rawseti(L: *mut lua_State, idx: c_int, n: lua_Integer);
+    pub fn lua_rawsetp(L: *mut lua_State, idx: c_int, p: *const c_void);
+    pub fn lua_setmetatable(L: *mut lua_State, objindex: c_int) -> c_int;
+    pub fn lua_setiuservalue(L: *mut lua_State, idx: c_int, n: c_int) -> c_int;
+
+    //
+    // 'load' and 'call' functions (load and run Lua code)
+    //
+    pub fn lua_callk(
+        L: *mut lua_State,
+        nargs: c_int,
+        nresults: c_int,
+        ctx: lua_KContext,
+        k: Option<lua_KFunction>,
+    );
+    pub fn lua_pcallk(
+        L: *mut lua_State,
+        nargs: c_int,
+        nresults: c_int,
+        errfunc: c_int,
+        ctx: lua_KContext,
+        k: Option<lua_KFunction>,
+    ) -> c_int;
+
+    pub fn lua_load(
+        L: *mut lua_State,
+        reader: lua_Reader,
+        data: *mut c_void,
+        chunkname: *const c_char,
+        mode: *const c_char,
+    ) -> c_int;
+
+    pub fn lua_dump(L: *mut lua_State, writer: lua_Writer, data: *mut c_void, strip: c_int) -> c_int;
+}
+
+#[inline(always)]
+pub unsafe fn lua_call(L: *mut lua_State, n: c_int, r: c_int) {
+    lua_callk(L, n, r, 0, None)
+}
+
+#[inline(always)]
+pub unsafe fn lua_pcall(L: *mut lua_State, n: c_int, r: c_int, f: c_int) -> c_int {
+    lua_pcallk(L, n, r, f, 0, None)
+}
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua54", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    //
+    // Coroutine functions
+    //
+    pub fn lua_yieldk(
+        L: *mut lua_State,
+        nresults: c_int,
+        ctx: lua_KContext,
+        k: Option<lua_KFunction>,
+    ) -> c_int;
+    pub fn lua_resume(L: *mut lua_State, from: *mut lua_State, narg: c_int, nres: *mut c_int) -> c_int;
+    pub fn lua_status(L: *mut lua_State) -> c_int;
+    pub fn lua_isyieldable(L: *mut lua_State) -> c_int;
+}
+
+#[inline(always)]
+pub unsafe fn lua_yield(L: *mut lua_State, n: c_int) -> c_int {
+    lua_yieldk(L, n, 0, None)
+}
+
+//
+// Warning-related functions
+//
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua54", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    pub fn lua_setwarnf(L: *mut lua_State, f: Option<lua_WarnFunction>, ud: *mut c_void);
+    pub fn lua_warning(L: *mut lua_State, msg: *const c_char, tocont: c_int);
+}
+
+//
+// Garbage-collection function and options
+//
+pub const LUA_GCSTOP: c_int = 0;
+pub const LUA_GCRESTART: c_int = 1;
+pub const LUA_GCCOLLECT: c_int = 2;
+pub const LUA_GCCOUNT: c_int = 3;
+pub const LUA_GCCOUNTB: c_int = 4;
+pub const LUA_GCSTEP: c_int = 5;
+pub const LUA_GCSETPAUSE: c_int = 6;
+pub const LUA_GCSETSTEPMUL: c_int = 7;
+pub const LUA_GCISRUNNING: c_int = 9;
+pub const LUA_GCGEN: c_int = 10;
+pub const LUA_GCINC: c_int = 11;
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua54", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    pub fn lua_gc(L: *mut lua_State, what: c_int, ...) -> c_int;
+}
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua54", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    //
+    // Miscellaneous functions
+    //
+    #[link_name = "lua_error"]
+    fn lua_error_(L: *mut lua_State) -> c_int;
+    pub fn lua_next(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_concat(L: *mut lua_State, n: c_int);
+    pub fn lua_len(L: *mut lua_State, idx: c_int);
+    pub fn lua_stringtonumber(L: *mut lua_State, s: *const c_char) -> usize;
+    pub fn lua_getallocf(L: *mut lua_State, ud: *mut *mut c_void) -> lua_Alloc;
+    pub fn lua_setallocf(L: *mut lua_State, f: lua_Alloc, ud: *mut c_void);
+
+    pub fn lua_toclose(L: *mut lua_State, idx: c_int);
+    pub fn lua_closeslot(L: *mut lua_State, idx: c_int);
+}
+
+// lua_error does not return but is declared to return int, and Rust translates
+// ! to void which can cause link-time errors if the platform linker is aware
+// of return types and requires they match (for example: wasm does this).
+#[inline(always)]
+pub unsafe fn lua_error(L: *mut lua_State) -> ! {
+    lua_error_(L);
+    unreachable!();
+}
+
+//
+// Some useful macros (implemented as Rust functions)
+//
+#[inline(always)]
+pub unsafe fn lua_getextraspace(L: *mut lua_State) -> *mut c_void {
+    (L as *mut c_char).sub(LUA_EXTRASPACE) as *mut c_void
+}
+
+#[inline(always)]
+pub unsafe fn lua_tonumber(L: *mut lua_State, i: c_int) -> lua_Number {
+    lua_tonumberx(L, i, ptr::null_mut())
+}
+
+#[inline(always)]
+pub unsafe fn lua_tointeger(L: *mut lua_State, i: c_int) -> lua_Integer {
+    lua_tointegerx(L, i, ptr::null_mut())
+}
+
+#[inline(always)]
+pub unsafe fn lua_pop(L: *mut lua_State, n: c_int) {
+    lua_settop(L, -n - 1)
+}
+
+#[inline(always)]
+pub unsafe fn lua_newtable(L: *mut lua_State) {
+    lua_createtable(L, 0, 0)
+}
+
+#[inline(always)]
+pub unsafe fn lua_register(L: *mut lua_State, n: *const c_char, f: lua_CFunction) {
+    lua_pushcfunction(L, f);
+    lua_setglobal(L, n)
+}
+
+#[inline(always)]
+pub unsafe fn lua_pushcfunction(L: *mut lua_State, f: lua_CFunction) {
+    lua_pushcclosure(L, f, 0)
+}
+
+#[inline(always)]
+pub unsafe fn lua_isfunction(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TFUNCTION) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_istable(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TTABLE) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_islightuserdata(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TLIGHTUSERDATA) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_isnil(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TNIL) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_isboolean(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TBOOLEAN) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_isthread(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TTHREAD) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_isnone(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TNONE) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_isnoneornil(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) <= 0) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_pushliteral(L: *mut lua_State, s: &'static CStr) {
+    lua_pushstring(L, s.as_ptr());
+}
+
+#[inline(always)]
+pub unsafe fn lua_pushglobaltable(L: *mut lua_State) -> c_int {
+    lua_rawgeti(L, LUA_REGISTRYINDEX, LUA_RIDX_GLOBALS)
+}
+
+#[inline(always)]
+pub unsafe fn lua_tolightuserdata(L: *mut lua_State, idx: c_int) -> *mut c_void {
+    if lua_islightuserdata(L, idx) != 0 {
+        return lua_touserdata(L, idx);
+    }
+    ptr::null_mut()
+}
+
+#[inline(always)]
+pub unsafe fn lua_tostring(L: *mut lua_State, i: c_int) -> *const c_char {
+    lua_tolstring(L, i, ptr::null_mut())
+}
+
+#[inline(always)]
+pub unsafe fn lua_insert(L: *mut lua_State, idx: c_int) {
+    lua_rotate(L, idx, 1)
+}
+
+#[inline(always)]
+pub unsafe fn lua_remove(L: *mut lua_State, idx: c_int) {
+    lua_rotate(L, idx, -1);
+    lua_pop(L, 1)
+}
+
+#[inline(always)]
+pub unsafe fn lua_replace(L: *mut lua_State, idx: c_int) {
+    lua_copy(L, -1, idx);
+    lua_pop(L, 1)
+}
+
+#[inline(always)]
+pub unsafe fn lua_xpush(from: *mut lua_State, to: *mut lua_State, idx: c_int) {
+    lua_pushvalue(from, idx);
+    lua_xmove(from, to, 1);
+}
+
+#[inline(always)]
+pub unsafe fn lua_newuserdata(L: *mut lua_State, sz: usize) -> *mut c_void {
+    lua_newuserdatauv(L, sz, 1)
+}
+
+#[inline(always)]
+pub unsafe fn lua_getuservalue(L: *mut lua_State, idx: c_int) -> c_int {
+    lua_getiuservalue(L, idx, 1)
+}
+
+#[inline(always)]
+pub unsafe fn lua_setuservalue(L: *mut lua_State, idx: c_int) -> c_int {
+    lua_setiuservalue(L, idx, 1)
+}
+
+//
+// Debug API
+//
+
+// Maximum size for the description of the source of a function in debug information.
+const LUA_IDSIZE: usize = 60;
+
+// Event codes
+pub const LUA_HOOKCALL: c_int = 0;
+pub const LUA_HOOKRET: c_int = 1;
+pub const LUA_HOOKLINE: c_int = 2;
+pub const LUA_HOOKCOUNT: c_int = 3;
+pub const LUA_HOOKTAILCALL: c_int = 4;
+
+// Event masks
+pub const LUA_MASKCALL: c_int = 1 << (LUA_HOOKCALL as usize);
+pub const LUA_MASKRET: c_int = 1 << (LUA_HOOKRET as usize);
+pub const LUA_MASKLINE: c_int = 1 << (LUA_HOOKLINE as usize);
+pub const LUA_MASKCOUNT: c_int = 1 << (LUA_HOOKCOUNT as usize);
+
+/// Type for functions to be called on debug events.
+pub type lua_Hook = unsafe extern "C-unwind" fn(L: *mut lua_State, ar: *mut lua_Debug);
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua54", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    pub fn lua_getstack(L: *mut lua_State, level: c_int, ar: *mut lua_Debug) -> c_int;
+    pub fn lua_getinfo(L: *mut lua_State, what: *const c_char, ar: *mut lua_Debug) -> c_int;
+    pub fn lua_getlocal(L: *mut lua_State, ar: *const lua_Debug, n: c_int) -> *const c_char;
+    pub fn lua_setlocal(L: *mut lua_State, ar: *const lua_Debug, n: c_int) -> *const c_char;
+    pub fn lua_getupvalue(L: *mut lua_State, funcindex: c_int, n: c_int) -> *const c_char;
+    pub fn lua_setupvalue(L: *mut lua_State, funcindex: c_int, n: c_int) -> *const c_char;
+
+    pub fn lua_upvalueid(L: *mut lua_State, fidx: c_int, n: c_int) -> *mut c_void;
+    pub fn lua_upvaluejoin(L: *mut lua_State, fidx1: c_int, n1: c_int, fidx2: c_int, n2: c_int);
+
+    pub fn lua_sethook(L: *mut lua_State, func: Option<lua_Hook>, mask: c_int, count: c_int);
+    pub fn lua_gethook(L: *mut lua_State) -> Option<lua_Hook>;
+    pub fn lua_gethookmask(L: *mut lua_State) -> c_int;
+    pub fn lua_gethookcount(L: *mut lua_State) -> c_int;
+}
+
+#[repr(C)]
+pub struct lua_Debug {
+    pub event: c_int,
+    pub name: *const c_char,
+    pub namewhat: *const c_char,
+    pub what: *const c_char,
+    pub source: *const c_char,
+    pub srclen: usize,
+    pub currentline: c_int,
+    pub linedefined: c_int,
+    pub lastlinedefined: c_int,
+    pub nups: c_uchar,
+    pub nparams: c_uchar,
+    pub isvararg: c_char,
+    pub istailcall: c_char,
+    pub ftransfer: c_ushort,
+    pub ntransfer: c_ushort,
+    pub short_src: [c_char; LUA_IDSIZE],
+    // lua.h mentions this is for private use
+    i_ci: *mut c_void,
+}

mlua-sys/src/lua54/lualib.rs

@@ -0,0 +1,32 @@
+//! Contains definitions from `lualib.h`.
+
+use std::os::raw::{c_char, c_int};
+
+use super::lua::lua_State;
+
+pub const LUA_COLIBNAME: *const c_char = cstr!("coroutine");
+pub const LUA_TABLIBNAME: *const c_char = cstr!("table");
+pub const LUA_IOLIBNAME: *const c_char = cstr!("io");
+pub const LUA_OSLIBNAME: *const c_char = cstr!("os");
+pub const LUA_STRLIBNAME: *const c_char = cstr!("string");
+pub const LUA_UTF8LIBNAME: *const c_char = cstr!("utf8");
+pub const LUA_MATHLIBNAME: *const c_char = cstr!("math");
+pub const LUA_DBLIBNAME: *const c_char = cstr!("debug");
+pub const LUA_LOADLIBNAME: *const c_char = cstr!("package");
+
+#[cfg_attr(all(windows, raw_dylib), link(name = "lua54", kind = "raw-dylib"))]
+unsafe extern "C-unwind" {
+    pub fn luaopen_base(L: *mut lua_State) -> c_int;
+    pub fn luaopen_coroutine(L: *mut lua_State) -> c_int;
+    pub fn luaopen_table(L: *mut lua_State) -> c_int;
+    pub fn luaopen_io(L: *mut lua_State) -> c_int;
+    pub fn luaopen_os(L: *mut lua_State) -> c_int;
+    pub fn luaopen_string(L: *mut lua_State) -> c_int;
+    pub fn luaopen_utf8(L: *mut lua_State) -> c_int;
+    pub fn luaopen_math(L: *mut lua_State) -> c_int;
+    pub fn luaopen_debug(L: *mut lua_State) -> c_int;
+    pub fn luaopen_package(L: *mut lua_State) -> c_int;
+
+    // open all builtin libraries
+    pub fn luaL_openlibs(L: *mut lua_State);
+}

mlua-sys/src/lua54/mod.rs

@@ -0,0 +1,9 @@
+//! Low level bindings to Lua 5.4.
+
+pub use lauxlib::*;
+pub use lua::*;
+pub use lualib::*;
+
+pub mod lauxlib;
+pub mod lua;
+pub mod lualib;

mlua-sys/src/luau/compat.rs

@@ -0,0 +1,564 @@
+//! MLua compatibility layer for Luau.
+//!
+//! Based on github.com/keplerproject/lua-compat-5.3
+
+use std::ffi::CStr;
+use std::os::raw::{c_char, c_int, c_void};
+use std::{mem, ptr};
+
+use super::lauxlib::*;
+use super::lua::*;
+use super::luacode::*;
+
+pub const LUA_RESUMEERROR: c_int = -1;
+
+unsafe fn compat53_reverse(L: *mut lua_State, mut a: c_int, mut b: c_int) {
+    while a < b {
+        lua_pushvalue(L, a);
+        lua_pushvalue(L, b);
+        lua_replace(L, a);
+        lua_replace(L, b);
+        a += 1;
+        b -= 1;
+    }
+}
+
+const COMPAT53_LEVELS1: c_int = 12; // size of the first part of the stack
+const COMPAT53_LEVELS2: c_int = 10; // size of the second part of the stack
+
+unsafe fn compat53_findfield(L: *mut lua_State, objidx: c_int, level: c_int) -> c_int {
+    if level == 0 || lua_istable(L, -1) == 0 {
+        return 0; // not found
+    }
+
+    lua_pushnil(L); // start 'next' loop
+    while lua_next(L, -2) != 0 {
+        // for each pair in table
+        if lua_type(L, -2) == LUA_TSTRING {
+            // ignore non-string keys
+            if lua_rawequal(L, objidx, -1) != 0 {
+                // found object?
+                lua_pop(L, 1); // remove value (but keep name)
+                return 1;
+            } else if compat53_findfield(L, objidx, level - 1) != 0 {
+                // try recursively
+                lua_remove(L, -2); // remove table (but keep name)
+                lua_pushliteral(L, c".");
+                lua_insert(L, -2); // place '.' between the two names
+                lua_concat(L, 3);
+                return 1;
+            }
+        }
+        lua_pop(L, 1); // remove value
+    }
+    0 // not found
+}
+
+unsafe fn compat53_pushglobalfuncname(L: *mut lua_State, level: c_int, ar: *mut lua_Debug) -> c_int {
+    let top = lua_gettop(L);
+    // push function
+    lua_getinfo(L, level, cstr!("f"), ar);
+    lua_pushvalue(L, LUA_GLOBALSINDEX);
+    if compat53_findfield(L, top + 1, 2) != 0 {
+        lua_copy(L, -1, top + 1); // move name to proper place
+        lua_pop(L, 2); // remove pushed values
+        1
+    } else {
+        lua_settop(L, top); // remove function and global table
+        0
+    }
+}
+
+unsafe fn compat53_pushfuncname(L: *mut lua_State, level: c_int, ar: *mut lua_Debug) {
+    if !(*ar).name.is_null() {
+        // is there a name?
+        lua_pushfstring(L, cstr!("function '%s'"), (*ar).name);
+    } else if compat53_pushglobalfuncname(L, level, ar) != 0 {
+        lua_pushfstring(L, cstr!("function '%s'"), lua_tostring(L, -1));
+        lua_remove(L, -2); // remove name
+    } else {
+        lua_pushliteral(L, c"?");
+    }
+}
+
+//
+// lua ported functions
+//
+
+pub unsafe fn lua_rotate(L: *mut lua_State, mut idx: c_int, mut n: c_int) {
+    idx = lua_absindex(L, idx);
+    if n > 0 {
+        // Faster version
+        for _ in 0..n {
+            lua_insert(L, idx);
+        }
+        return;
+    }
+    let n_elems = lua_gettop(L) - idx + 1;
+    if n < 0 {
+        n += n_elems;
+    }
+    if n > 0 && n < n_elems {
+        luaL_checkstack(L, 2, cstr!("not enough stack slots available"));
+        n = n_elems - n;
+        compat53_reverse(L, idx, idx + n - 1);
+        compat53_reverse(L, idx + n, idx + n_elems - 1);
+        compat53_reverse(L, idx, idx + n_elems - 1);
+    }
+}
+
+#[inline(always)]
+pub unsafe fn lua_copy(L: *mut lua_State, fromidx: c_int, toidx: c_int) {
+    let abs_to = lua_absindex(L, toidx);
+    luaL_checkstack(L, 1, cstr!("not enough stack slots available"));
+    lua_pushvalue(L, fromidx);
+    lua_replace(L, abs_to);
+}
+
+#[inline(always)]
+pub unsafe fn lua_isinteger(L: *mut lua_State, idx: c_int) -> c_int {
+    if lua_type(L, idx) == LUA_TNUMBER {
+        let n = lua_tonumber(L, idx);
+        let i = lua_tointeger(L, idx);
+        // Lua 5.3+ returns "false" for `-0.0`
+        if n.to_bits() == (i as lua_Number).to_bits() {
+            return 1;
+        }
+    }
+    0
+}
+
+#[inline(always)]
+pub unsafe fn lua_pushinteger(L: *mut lua_State, i: lua_Integer) {
+    lua_pushnumber(L, i as lua_Number);
+}
+
+#[inline(always)]
+pub unsafe fn lua_tointeger(L: *mut lua_State, i: c_int) -> lua_Integer {
+    lua_tointegerx(L, i, ptr::null_mut())
+}
+
+pub unsafe fn lua_tointegerx(L: *mut lua_State, i: c_int, isnum: *mut c_int) -> lua_Integer {
+    let mut ok = 0;
+    let n = lua_tonumberx(L, i, &mut ok);
+    let n_int = n as lua_Integer;
+    if ok != 0 && (n - n_int as lua_Number).abs() < lua_Number::EPSILON {
+        if !isnum.is_null() {
+            *isnum = 1;
+        }
+        return n_int;
+    }
+    if !isnum.is_null() {
+        *isnum = 0;
+    }
+    0
+}
+
+#[inline(always)]
+pub unsafe fn lua_rawlen(L: *mut lua_State, idx: c_int) -> usize {
+    lua_objlen(L, idx)
+}
+
+#[inline(always)]
+pub unsafe fn lua_pushlstring(L: *mut lua_State, s: *const c_char, l: usize) -> *const c_char {
+    if l == 0 {
+        lua_pushlstring_(L, cstr!(""), 0);
+    } else {
+        lua_pushlstring_(L, s, l);
+    }
+    lua_tostring(L, -1)
+}
+
+#[inline(always)]
+pub unsafe fn lua_pushstring(L: *mut lua_State, s: *const c_char) -> *const c_char {
+    lua_pushstring_(L, s);
+    lua_tostring(L, -1)
+}
+
+#[inline(always)]
+pub unsafe fn lua_geti(L: *mut lua_State, mut idx: c_int, n: lua_Integer) -> c_int {
+    idx = lua_absindex(L, idx);
+    lua_pushinteger(L, n);
+    lua_gettable(L, idx)
+}
+
+#[inline(always)]
+pub unsafe fn lua_rawgeti(L: *mut lua_State, idx: c_int, n: lua_Integer) -> c_int {
+    let n = n.try_into().expect("cannot convert index from lua_Integer");
+    lua_rawgeti_(L, idx, n)
+}
+
+#[inline(always)]
+pub unsafe fn lua_rawgetp(L: *mut lua_State, idx: c_int, p: *const c_void) -> c_int {
+    let abs_i = lua_absindex(L, idx);
+    lua_pushlightuserdata(L, p as *mut c_void);
+    lua_rawget(L, abs_i)
+}
+
+#[inline(always)]
+pub unsafe fn lua_getuservalue(L: *mut lua_State, mut idx: c_int) -> c_int {
+    luaL_checkstack(L, 2, cstr!("not enough stack slots available"));
+    idx = lua_absindex(L, idx);
+    lua_pushliteral(L, c"__mlua_uservalues");
+    if lua_rawget(L, LUA_REGISTRYINDEX) != LUA_TTABLE {
+        return LUA_TNIL;
+    }
+    lua_pushvalue(L, idx);
+    lua_rawget(L, -2);
+    lua_remove(L, -2);
+    lua_type(L, -1)
+}
+
+#[inline(always)]
+pub unsafe fn lua_seti(L: *mut lua_State, mut idx: c_int, n: lua_Integer) {
+    luaL_checkstack(L, 1, cstr!("not enough stack slots available"));
+    idx = lua_absindex(L, idx);
+    lua_pushinteger(L, n);
+    lua_insert(L, -2);
+    lua_settable(L, idx);
+}
+
+#[inline(always)]
+pub unsafe fn lua_rawseti(L: *mut lua_State, idx: c_int, n: lua_Integer) {
+    let n = n.try_into().expect("cannot convert index from lua_Integer");
+    lua_rawseti_(L, idx, n)
+}
+
+#[inline(always)]
+pub unsafe fn lua_rawsetp(L: *mut lua_State, idx: c_int, p: *const c_void) {
+    let abs_i = lua_absindex(L, idx);
+    luaL_checkstack(L, 1, cstr!("not enough stack slots available"));
+    lua_pushlightuserdata(L, p as *mut c_void);
+    lua_insert(L, -2);
+    lua_rawset(L, abs_i);
+}
+
+#[inline(always)]
+pub unsafe fn lua_setuservalue(L: *mut lua_State, mut idx: c_int) {
+    luaL_checkstack(L, 4, cstr!("not enough stack slots available"));
+    idx = lua_absindex(L, idx);
+    lua_pushliteral(L, c"__mlua_uservalues");
+    lua_pushvalue(L, -1);
+    if lua_rawget(L, LUA_REGISTRYINDEX) != LUA_TTABLE {
+        lua_pop(L, 1);
+        lua_createtable(L, 0, 2); // main table
+        lua_createtable(L, 0, 1); // metatable
+        lua_pushliteral(L, c"k");
+        lua_setfield(L, -2, cstr!("__mode"));
+        lua_setmetatable(L, -2);
+        lua_pushvalue(L, -2);
+        lua_pushvalue(L, -2);
+        lua_rawset(L, LUA_REGISTRYINDEX);
+    }
+    lua_replace(L, -2);
+    lua_pushvalue(L, idx);
+    lua_pushvalue(L, -3);
+    lua_remove(L, -4);
+    lua_rawset(L, -3);
+    lua_pop(L, 1);
+}
+
+#[inline(always)]
+pub unsafe fn lua_len(L: *mut lua_State, idx: c_int) {
+    match lua_type(L, idx) {
+        LUA_TSTRING => {
+            lua_pushnumber(L, lua_objlen(L, idx) as lua_Number);
+        }
+        LUA_TTABLE => {
+            if luaL_callmeta(L, idx, cstr!("__len")) == 0 {
+                lua_pushnumber(L, lua_objlen(L, idx) as lua_Number);
+            }
+        }
+        LUA_TUSERDATA if luaL_callmeta(L, idx, cstr!("__len")) != 0 => {}
+        _ => {
+            luaL_error(
+                L,
+                cstr!("attempt to get length of a %s value"),
+                lua_typename(L, lua_type(L, idx)),
+            );
+        }
+    }
+}
+
+#[inline(always)]
+pub unsafe fn lua_pushglobaltable(L: *mut lua_State) {
+    lua_pushvalue(L, LUA_GLOBALSINDEX);
+}
+
+#[inline(always)]
+pub unsafe fn lua_resume(L: *mut lua_State, from: *mut lua_State, narg: c_int, nres: *mut c_int) -> c_int {
+    let ret = lua_resume_(L, from, narg);
+    if (ret == LUA_OK || ret == LUA_YIELD) && !(nres.is_null()) {
+        *nres = lua_gettop(L);
+    }
+    ret
+}
+
+#[inline(always)]
+pub unsafe fn lua_resumex(L: *mut lua_State, from: *mut lua_State, narg: c_int, nres: *mut c_int) -> c_int {
+    let ret = if narg == LUA_RESUMEERROR {
+        lua_resumeerror(L, from)
+    } else {
+        lua_resume_(L, from, narg)
+    };
+    if (ret == LUA_OK || ret == LUA_YIELD) && !(nres.is_null()) {
+        *nres = lua_gettop(L);
+    }
+    ret
+}
+
+//
+// lauxlib ported functions
+//
+
+#[inline(always)]
+pub unsafe fn luaL_checkstack(L: *mut lua_State, sz: c_int, msg: *const c_char) {
+    if lua_checkstack(L, sz + LUA_MINSTACK) == 0 {
+        if !msg.is_null() {
+            luaL_error(L, cstr!("stack overflow (%s)"), msg);
+        } else {
+            lua_pushliteral(L, c"stack overflow");
+            lua_error(L);
+        }
+    }
+}
+
+#[inline(always)]
+pub unsafe fn luaL_checkinteger(L: *mut lua_State, narg: c_int) -> lua_Integer {
+    let mut isnum = 0;
+    let int = lua_tointegerx(L, narg, &mut isnum);
+    if isnum == 0 {
+        luaL_typeerror(L, narg, lua_typename(L, LUA_TNUMBER));
+    }
+    int
+}
+
+pub unsafe fn luaL_optinteger(L: *mut lua_State, narg: c_int, def: lua_Integer) -> lua_Integer {
+    if lua_isnoneornil(L, narg) != 0 {
+        def
+    } else {
+        luaL_checkinteger(L, narg)
+    }
+}
+
+#[inline(always)]
+pub unsafe fn luaL_getmetafield(L: *mut lua_State, obj: c_int, e: *const c_char) -> c_int {
+    if luaL_getmetafield_(L, obj, e) != 0 {
+        lua_type(L, -1)
+    } else {
+        LUA_TNIL
+    }
+}
+
+#[inline(always)]
+pub unsafe fn luaL_newmetatable(L: *mut lua_State, tname: *const c_char) -> c_int {
+    if luaL_newmetatable_(L, tname) != 0 {
+        lua_pushstring(L, tname);
+        lua_setfield(L, -2, cstr!("__type"));
+        1
+    } else {
+        0
+    }
+}
+
+pub unsafe fn luaL_loadbufferenv(
+    L: *mut lua_State,
+    data: *const c_char,
+    mut size: usize,
+    name: *const c_char,
+    mode: *const c_char,
+    mut env: c_int,
+) -> c_int {
+    unsafe extern "C" {
+        fn free(p: *mut c_void);
+    }
+
+    unsafe extern "C" fn data_dtor(_: *mut lua_State, data: *mut c_void) {
+        free(*(data as *mut *mut c_char) as *mut c_void);
+    }
+
+    let chunk_is_text = size == 0 || (*data as u8) >= b'\t';
+    if !mode.is_null() {
+        let modeb = CStr::from_ptr(mode).to_bytes();
+        if !chunk_is_text && !modeb.contains(&b'b') {
+            lua_pushfstring(L, cstr!("attempt to load a binary chunk (mode is '%s')"), mode);
+            return LUA_ERRSYNTAX;
+        } else if chunk_is_text && !modeb.contains(&b't') {
+            lua_pushfstring(L, cstr!("attempt to load a text chunk (mode is '%s')"), mode);
+            return LUA_ERRSYNTAX;
+        }
+    }
+
+    let status = if chunk_is_text {
+        if env < 0 {
+            env -= 1;
+        }
+        let data_ud = lua_newuserdatadtor(L, mem::size_of::<*mut c_char>(), data_dtor) as *mut *mut c_char;
+        let data = luau_compile_(data, size, ptr::null_mut(), &mut size);
+        ptr::write(data_ud, data);
+        // By deferring the `free(data)` to the userdata destructor, we ensure that
+        // even if `luau_load` throws an error, the `data` is still released.
+        let status = luau_load(L, name, data, size, env);
+        lua_replace(L, -2); // replace data with the result
+        status
+    } else {
+        luau_load(L, name, data, size, env)
+    };
+
+    if status != 0 {
+        if lua_isstring(L, -1) != 0 && CStr::from_ptr(lua_tostring(L, -1)) == c"not enough memory" {
+            // A case for Luau >= 0.679
+            return LUA_ERRMEM;
+        }
+        return LUA_ERRSYNTAX;
+    }
+
+    LUA_OK
+}
+
+#[inline(always)]
+pub unsafe fn luaL_loadbufferx(
+    L: *mut lua_State,
+    data: *const c_char,
+    size: usize,
+    name: *const c_char,
+    mode: *const c_char,
+) -> c_int {
+    luaL_loadbufferenv(L, data, size, name, mode, 0)
+}
+
+#[inline(always)]
+pub unsafe fn luaL_loadbuffer(
+    L: *mut lua_State,
+    data: *const c_char,
+    size: usize,
+    name: *const c_char,
+) -> c_int {
+    luaL_loadbufferenv(L, data, size, name, ptr::null(), 0)
+}
+
+#[inline(always)]
+pub unsafe fn luaL_len(L: *mut lua_State, idx: c_int) -> lua_Integer {
+    let mut isnum = 0;
+    luaL_checkstack(L, 1, cstr!("not enough stack slots available"));
+    lua_len(L, idx);
+    let res = lua_tointegerx(L, -1, &mut isnum);
+    lua_pop(L, 1);
+    if isnum == 0 {
+        luaL_error(L, cstr!("object length is not an integer"));
+    }
+    res
+}
+
+pub unsafe fn luaL_traceback(L: *mut lua_State, L1: *mut lua_State, msg: *const c_char, mut level: c_int) {
+    let mut ar: lua_Debug = mem::zeroed();
+    let top = lua_gettop(L);
+    let numlevels = lua_stackdepth(L);
+    let mark = if numlevels > COMPAT53_LEVELS1 + COMPAT53_LEVELS2 {
+        COMPAT53_LEVELS1
+    } else {
+        0
+    };
+
+    if !msg.is_null() {
+        lua_pushfstring(L, cstr!("%s\n"), msg);
+    }
+    lua_pushliteral(L, c"stack traceback:");
+    while lua_getinfo(L1, level, cstr!(""), &mut ar) != 0 {
+        if level + 1 == mark {
+            // too many levels?
+            lua_pushliteral(L, c"\n\t..."); // add a '...'
+            level = numlevels - COMPAT53_LEVELS2; // and skip to last ones
+        } else {
+            lua_getinfo(L1, level, cstr!("sln"), &mut ar);
+            lua_pushfstring(L, cstr!("\n\t%s:"), ar.short_src);
+            if ar.currentline > 0 {
+                lua_pushfstring(L, cstr!("%d:"), ar.currentline);
+            }
+            lua_pushliteral(L, c" in ");
+            compat53_pushfuncname(L, level, &mut ar);
+            lua_concat(L, lua_gettop(L) - top);
+        }
+        level += 1;
+    }
+    lua_concat(L, lua_gettop(L) - top);
+}
+
+pub unsafe fn luaL_tolstring(L: *mut lua_State, mut idx: c_int, len: *mut usize) -> *const c_char {
+    idx = lua_absindex(L, idx);
+    if luaL_callmeta(L, idx, cstr!("__tostring")) == 0 {
+        match lua_type(L, idx) {
+            LUA_TNIL => {
+                lua_pushliteral(L, c"nil");
+            }
+            LUA_TSTRING | LUA_TNUMBER => {
+                lua_pushvalue(L, idx);
+            }
+            LUA_TBOOLEAN => {
+                if lua_toboolean(L, idx) == 0 {
+                    lua_pushliteral(L, c"false");
+                } else {
+                    lua_pushliteral(L, c"true");
+                }
+            }
+            t => {
+                let tt = luaL_getmetafield(L, idx, cstr!("__type"));
+                let name = if tt == LUA_TSTRING {
+                    lua_tostring(L, -1)
+                } else {
+                    lua_typename(L, t)
+                };
+                lua_pushfstring(L, cstr!("%s: %p"), name, lua_topointer(L, idx));
+                if tt != LUA_TNIL {
+                    lua_replace(L, -2); // remove '__type'
+                }
+            }
+        };
+    } else if lua_isstring(L, -1) == 0 {
+        luaL_error(L, cstr!("'__tostring' must return a string"));
+    }
+    lua_tolstring(L, -1, len)
+}
+
+#[inline(always)]
+pub unsafe fn luaL_setmetatable(L: *mut lua_State, tname: *const c_char) {
+    luaL_checkstack(L, 1, cstr!("not enough stack slots available"));
+    luaL_getmetatable(L, tname);
+    lua_setmetatable(L, -2);
+}
+
+pub unsafe fn luaL_getsubtable(L: *mut lua_State, idx: c_int, fname: *const c_char) -> c_int {
+    let abs_i = lua_absindex(L, idx);
+    luaL_checkstack(L, 3, cstr!("not enough stack slots available"));
+    lua_pushstring_(L, fname);
+    if lua_gettable(L, abs_i) == LUA_TTABLE {
+        return 1;
+    }
+    lua_pop(L, 1);
+    lua_newtable(L);
+    lua_pushstring_(L, fname);
+    lua_pushvalue(L, -2);
+    lua_settable(L, abs_i);
+    0
+}
+
+pub unsafe fn luaL_requiref(L: *mut lua_State, modname: *const c_char, openf: lua_CFunction, glb: c_int) {
+    luaL_checkstack(L, 3, cstr!("not enough stack slots available"));
+    luaL_getsubtable(L, LUA_REGISTRYINDEX, cstr!("_LOADED"));
+    if lua_getfield(L, -1, modname) == LUA_TNIL {
+        lua_pop(L, 1);
+        lua_pushcfunction(L, openf);
+        lua_pushstring(L, modname);
+        lua_call(L, 1, 1);
+        lua_pushvalue(L, -1);
+        lua_setfield(L, -3, modname);
+    }
+    if glb != 0 {
+        lua_pushvalue(L, -1);
+        lua_setglobal(L, modname);
+    } else {
+        lua_pushnil(L);
+        lua_setglobal(L, modname);
+    }
+    lua_replace(L, -2);
+}

mlua-sys/src/luau/lauxlib.rs

@@ -0,0 +1,211 @@
+//! Contains definitions from `lualib.h`.
+
+use std::os::raw::{c_char, c_float, c_int, c_void};
+use std::ptr;
+
+use super::lua::{self, lua_CFunction, lua_Number, lua_State, lua_Unsigned, LUA_REGISTRYINDEX};
+
+#[repr(C)]
+pub struct luaL_Reg {
+    pub name: *const c_char,
+    pub func: lua_CFunction,
+}
+
+unsafe extern "C-unwind" {
+    pub fn luaL_register(L: *mut lua_State, libname: *const c_char, l: *const luaL_Reg);
+    #[link_name = "luaL_getmetafield"]
+    pub fn luaL_getmetafield_(L: *mut lua_State, obj: c_int, e: *const c_char) -> c_int;
+    pub fn luaL_callmeta(L: *mut lua_State, obj: c_int, e: *const c_char) -> c_int;
+    #[link_name = "luaL_typeerrorL"]
+    pub fn luaL_typeerror(L: *mut lua_State, narg: c_int, tname: *const c_char) -> !;
+    #[link_name = "luaL_argerrorL"]
+    pub fn luaL_argerror(L: *mut lua_State, narg: c_int, extramsg: *const c_char) -> !;
+    pub fn luaL_checklstring(L: *mut lua_State, narg: c_int, l: *mut usize) -> *const c_char;
+    pub fn luaL_optlstring(
+        L: *mut lua_State,
+        narg: c_int,
+        def: *const c_char,
+        l: *mut usize,
+    ) -> *const c_char;
+    pub fn luaL_checknumber(L: *mut lua_State, narg: c_int) -> lua_Number;
+    pub fn luaL_optnumber(L: *mut lua_State, narg: c_int, def: lua_Number) -> lua_Number;
+
+    pub fn luaL_checkboolean(L: *mut lua_State, narg: c_int) -> c_int;
+    pub fn luaL_optboolean(L: *mut lua_State, narg: c_int, def: c_int) -> c_int;
+
+    #[link_name = "luaL_checkinteger"]
+    pub fn luaL_checkinteger_(L: *mut lua_State, narg: c_int) -> c_int;
+    #[link_name = "luaL_optinteger"]
+    pub fn luaL_optinteger_(L: *mut lua_State, narg: c_int, def: c_int) -> c_int;
+    pub fn luaL_checkunsigned(L: *mut lua_State, narg: c_int) -> lua_Unsigned;
+    pub fn luaL_optunsigned(L: *mut lua_State, narg: c_int, def: lua_Unsigned) -> lua_Unsigned;
+
+    pub fn luaL_checkvector(L: *mut lua_State, narg: c_int) -> *const c_float;
+    pub fn luaL_optvector(L: *mut lua_State, narg: c_int, def: *const c_float) -> *const c_float;
+
+    #[link_name = "luaL_checkstack"]
+    pub fn luaL_checkstack_(L: *mut lua_State, sz: c_int, msg: *const c_char);
+    pub fn luaL_checktype(L: *mut lua_State, narg: c_int, t: c_int);
+    pub fn luaL_checkany(L: *mut lua_State, narg: c_int);
+
+    #[link_name = "luaL_newmetatable"]
+    pub fn luaL_newmetatable_(L: *mut lua_State, tname: *const c_char) -> c_int;
+    pub fn luaL_checkudata(L: *mut lua_State, ud: c_int, tname: *const c_char) -> *mut c_void;
+
+    pub fn luaL_checkbuffer(L: *mut lua_State, narg: c_int, len: *mut usize) -> *mut c_void;
+
+    pub fn luaL_where(L: *mut lua_State, lvl: c_int);
+
+    #[link_name = "luaL_errorL"]
+    pub fn luaL_error(L: *mut lua_State, fmt: *const c_char, ...) -> !;
+
+    pub fn luaL_checkoption(
+        L: *mut lua_State,
+        narg: c_int,
+        def: *const c_char,
+        lst: *const *const c_char,
+    ) -> c_int;
+
+    #[link_name = "luaL_tolstring"]
+    pub fn luaL_tolstring_(L: *mut lua_State, idx: c_int, len: *mut usize) -> *const c_char;
+
+    pub fn luaL_newstate() -> *mut lua_State;
+
+    pub fn luaL_findtable(
+        L: *mut lua_State,
+        idx: c_int,
+        fname: *const c_char,
+        szhint: c_int,
+    ) -> *const c_char;
+
+    pub fn luaL_typename(L: *mut lua_State, idx: c_int) -> *const c_char;
+
+    pub fn luaL_callyieldable(L: *mut lua_State, nargs: c_int, nresults: c_int) -> c_int;
+
+    // sandbox libraries and globals
+    #[link_name = "luaL_sandbox"]
+    pub fn luaL_sandbox_(L: *mut lua_State);
+    pub fn luaL_sandboxthread(L: *mut lua_State);
+}
+
+//
+// Some useful macros (implemented as Rust functions)
+//
+
+#[inline(always)]
+pub unsafe fn luaL_argcheck(L: *mut lua_State, cond: c_int, arg: c_int, extramsg: *const c_char) {
+    if cond == 0 {
+        luaL_argerror(L, arg, extramsg);
+    }
+}
+
+#[inline(always)]
+pub unsafe fn luaL_argexpected(L: *mut lua_State, cond: c_int, arg: c_int, tname: *const c_char) {
+    if cond == 0 {
+        luaL_typeerror(L, arg, tname);
+    }
+}
+
+#[inline(always)]
+pub unsafe fn luaL_checkstring(L: *mut lua_State, n: c_int) -> *const c_char {
+    luaL_checklstring(L, n, ptr::null_mut())
+}
+
+#[inline(always)]
+pub unsafe fn luaL_optstring(L: *mut lua_State, n: c_int, d: *const c_char) -> *const c_char {
+    luaL_optlstring(L, n, d, ptr::null_mut())
+}
+
+// TODO: luaL_opt
+
+#[inline(always)]
+pub unsafe fn luaL_getmetatable(L: *mut lua_State, n: *const c_char) -> c_int {
+    lua::lua_getfield(L, LUA_REGISTRYINDEX, n)
+}
+
+#[inline(always)]
+pub unsafe fn luaL_ref(L: *mut lua_State, t: c_int) -> c_int {
+    assert_eq!(t, LUA_REGISTRYINDEX);
+    let r = lua::lua_ref(L, -1);
+    lua::lua_pop(L, 1);
+    r
+}
+
+#[inline(always)]
+pub unsafe fn luaL_unref(L: *mut lua_State, t: c_int, r#ref: c_int) {
+    assert_eq!(t, LUA_REGISTRYINDEX);
+    lua::lua_unref(L, r#ref)
+}
+
+pub unsafe fn luaL_sandbox(L: *mut lua_State, enabled: c_int) {
+    use super::lua::*;
+
+    // set all libraries to read-only
+    lua_pushnil(L);
+    while lua_next(L, LUA_GLOBALSINDEX) != 0 {
+        if lua_istable(L, -1) != 0 {
+            lua_setreadonly(L, -1, enabled);
+        }
+        lua_pop(L, 1);
+    }
+
+    // set all builtin metatables to read-only
+    lua_pushliteral(L, c"");
+    if lua_getmetatable(L, -1) != 0 {
+        lua_setreadonly(L, -1, enabled);
+        lua_pop(L, 2);
+    } else {
+        lua_pop(L, 1);
+    }
+
+    // set globals to readonly and activate safeenv since the env is immutable
+    lua_setreadonly(L, LUA_GLOBALSINDEX, enabled);
+    lua_setsafeenv(L, LUA_GLOBALSINDEX, enabled);
+}
+
+//
+// Generic Buffer Manipulation
+//
+
+/// Buffer size used for on-stack string operations. This limit depends on native stack size.
+pub const LUA_BUFFERSIZE: usize = 512;
+
+#[repr(C)]
+pub struct luaL_Strbuf {
+    p: *mut c_char,   // current position in buffer
+    end: *mut c_char, // end of the current buffer
+    L: *mut lua_State,
+    storage: *mut c_void, // TString
+    buffer: [c_char; LUA_BUFFERSIZE],
+}
+
+// For compatibility
+pub type luaL_Buffer = luaL_Strbuf;
+
+unsafe extern "C-unwind" {
+    pub fn luaL_buffinit(L: *mut lua_State, B: *mut luaL_Strbuf);
+    pub fn luaL_buffinitsize(L: *mut lua_State, B: *mut luaL_Strbuf, size: usize) -> *mut c_char;
+    pub fn luaL_prepbuffsize(B: *mut luaL_Strbuf, size: usize) -> *mut c_char;
+    pub fn luaL_addlstring(B: *mut luaL_Strbuf, s: *const c_char, l: usize);
+    pub fn luaL_addvalue(B: *mut luaL_Strbuf);
+    pub fn luaL_addvalueany(B: *mut luaL_Strbuf, idx: c_int);
+    pub fn luaL_pushresult(B: *mut luaL_Strbuf);
+    pub fn luaL_pushresultsize(B: *mut luaL_Strbuf, size: usize);
+}
+
+pub unsafe fn luaL_addchar(B: *mut luaL_Strbuf, c: c_char) {
+    if (*B).p >= (*B).end {
+        luaL_prepbuffsize(B, 1);
+    }
+    *(*B).p = c;
+    (*B).p = (*B).p.add(1);
+}
+
+pub unsafe fn luaL_addstring(B: *mut luaL_Strbuf, s: *const c_char) {
+    // Calculate length of s
+    let mut len = 0;
+    while *s.add(len) != 0 {
+        len += 1;
+    }
+    luaL_addlstring(B, s, len);
+}

mlua-sys/src/luau/lua.rs

@@ -0,0 +1,548 @@
+//! Contains definitions from `lua.h`.
+
+use std::ffi::CStr;
+use std::marker::{PhantomData, PhantomPinned};
+use std::os::raw::{c_char, c_double, c_float, c_int, c_uint, c_void};
+use std::{mem, ptr};
+
+// Option for multiple returns in 'lua_pcall' and 'lua_call'
+pub const LUA_MULTRET: c_int = -1;
+
+// Max number of Lua stack slots
+const LUAI_MAXCSTACK: c_int = 1000000;
+
+// Number of valid Lua userdata tags
+pub const LUA_UTAG_LIMIT: c_int = 128;
+
+// Number of valid Lua lightuserdata tags
+pub const LUA_LUTAG_LIMIT: c_int = 128;
+
+//
+// Pseudo-indices
+//
+pub const LUA_REGISTRYINDEX: c_int = -LUAI_MAXCSTACK - 2000;
+pub const LUA_ENVIRONINDEX: c_int = -LUAI_MAXCSTACK - 2001;
+pub const LUA_GLOBALSINDEX: c_int = -LUAI_MAXCSTACK - 2002;
+
+pub const fn lua_upvalueindex(i: c_int) -> c_int {
+    LUA_GLOBALSINDEX - i
+}
+
+//
+// Thread status
+//
+pub const LUA_OK: c_int = 0;
+pub const LUA_YIELD: c_int = 1;
+pub const LUA_ERRRUN: c_int = 2;
+pub const LUA_ERRSYNTAX: c_int = 3;
+pub const LUA_ERRMEM: c_int = 4;
+pub const LUA_ERRERR: c_int = 5;
+
+/// A raw Lua state associated with a thread.
+#[repr(C)]
+pub struct lua_State {
+    _data: [u8; 0],
+    _marker: PhantomData<(*mut u8, PhantomPinned)>,
+}
+
+//
+// Basic types
+//
+pub const LUA_TNONE: c_int = -1;
+
+pub const LUA_TNIL: c_int = 0;
+pub const LUA_TBOOLEAN: c_int = 1;
+
+pub const LUA_TLIGHTUSERDATA: c_int = 2;
+pub const LUA_TNUMBER: c_int = 3;
+pub const LUA_TVECTOR: c_int = 4;
+
+pub const LUA_TSTRING: c_int = 5;
+pub const LUA_TTABLE: c_int = 6;
+pub const LUA_TFUNCTION: c_int = 7;
+pub const LUA_TUSERDATA: c_int = 8;
+pub const LUA_TTHREAD: c_int = 9;
+pub const LUA_TBUFFER: c_int = 10;
+
+/// Guaranteed number of Lua stack slots available to a C function.
+pub const LUA_MINSTACK: c_int = 20;
+
+/// A Lua number, usually equivalent to `f64`.
+pub type lua_Number = c_double;
+
+/// A Lua integer, usually equivalent to `i64`
+#[cfg(target_pointer_width = "32")]
+pub type lua_Integer = i32;
+#[cfg(target_pointer_width = "64")]
+pub type lua_Integer = i64;
+
+/// A Lua unsigned integer, equivalent to `u32`.
+pub type lua_Unsigned = c_uint;
+
+/// Type for native C functions that can be passed to Lua.
+pub type lua_CFunction = unsafe extern "C-unwind" fn(L: *mut lua_State) -> c_int;
+pub type lua_Continuation = unsafe extern "C-unwind" fn(L: *mut lua_State, status: c_int) -> c_int;
+
+/// Type for userdata destructor functions (no unwinding).
+pub type lua_Destructor = unsafe extern "C" fn(L: *mut lua_State, *mut c_void);
+
+/// Type for memory-allocation functions (no unwinding).
+pub type lua_Alloc =
+    unsafe extern "C" fn(ud: *mut c_void, ptr: *mut c_void, osize: usize, nsize: usize) -> *mut c_void;
+
+/// Returns Luau release version (eg. `0.xxx`).
+pub const fn luau_version() -> Option<&'static str> {
+    option_env!("LUAU_VERSION")
+}
+
+unsafe extern "C-unwind" {
+    //
+    // State manipulation
+    //
+    pub fn lua_newstate(f: lua_Alloc, ud: *mut c_void) -> *mut lua_State;
+    pub fn lua_close(L: *mut lua_State);
+    pub fn lua_newthread(L: *mut lua_State) -> *mut lua_State;
+    pub fn lua_mainthread(L: *mut lua_State) -> *mut lua_State;
+    pub fn lua_resetthread(L: *mut lua_State);
+    pub fn lua_isthreadreset(L: *mut lua_State) -> c_int;
+
+    //
+    // Basic stack manipulation
+    //
+    pub fn lua_absindex(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_gettop(L: *mut lua_State) -> c_int;
+    pub fn lua_settop(L: *mut lua_State, idx: c_int);
+    pub fn lua_pushvalue(L: *mut lua_State, idx: c_int);
+    pub fn lua_remove(L: *mut lua_State, idx: c_int);
+    pub fn lua_insert(L: *mut lua_State, idx: c_int);
+    pub fn lua_replace(L: *mut lua_State, idx: c_int);
+    pub fn lua_checkstack(L: *mut lua_State, sz: c_int) -> c_int;
+    pub fn lua_rawcheckstack(L: *mut lua_State, sz: c_int);
+
+    pub fn lua_xmove(from: *mut lua_State, to: *mut lua_State, n: c_int);
+    pub fn lua_xpush(from: *mut lua_State, to: *mut lua_State, idx: c_int);
+
+    //
+    // Access functions (stack -> C)
+    //
+    pub fn lua_isnumber(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_isstring(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_iscfunction(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_isLfunction(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_isuserdata(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_type(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_typename(L: *mut lua_State, tp: c_int) -> *const c_char;
+
+    pub fn lua_equal(L: *mut lua_State, idx1: c_int, idx2: c_int) -> c_int;
+    pub fn lua_rawequal(L: *mut lua_State, idx1: c_int, idx2: c_int) -> c_int;
+    pub fn lua_lessthan(L: *mut lua_State, idx1: c_int, idx2: c_int) -> c_int;
+
+    pub fn lua_tonumberx(L: *mut lua_State, idx: c_int, isnum: *mut c_int) -> lua_Number;
+    #[link_name = "lua_tointegerx"]
+    pub fn lua_tointegerx_(L: *mut lua_State, idx: c_int, isnum: *mut c_int) -> c_int;
+    pub fn lua_tounsignedx(L: *mut lua_State, idx: c_int, isnum: *mut c_int) -> lua_Unsigned;
+    pub fn lua_tovector(L: *mut lua_State, idx: c_int) -> *const c_float;
+    pub fn lua_toboolean(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_tolstring(L: *mut lua_State, idx: c_int, len: *mut usize) -> *const c_char;
+    pub fn lua_tostringatom(L: *mut lua_State, idx: c_int, atom: *mut c_int) -> *const c_char;
+    pub fn lua_namecallatom(L: *mut lua_State, atom: *mut c_int) -> *const c_char;
+    pub fn lua_objlen(L: *mut lua_State, idx: c_int) -> usize;
+    pub fn lua_tocfunction(L: *mut lua_State, idx: c_int) -> Option<lua_CFunction>;
+    pub fn lua_tolightuserdata(L: *mut lua_State, idx: c_int) -> *mut c_void;
+    pub fn lua_tolightuserdatatagged(L: *mut lua_State, idx: c_int, tag: c_int) -> *mut c_void;
+    pub fn lua_touserdata(L: *mut lua_State, idx: c_int) -> *mut c_void;
+    pub fn lua_touserdatatagged(L: *mut lua_State, idx: c_int, tag: c_int) -> *mut c_void;
+    pub fn lua_userdatatag(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_lightuserdatatag(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_tothread(L: *mut lua_State, idx: c_int) -> *mut lua_State;
+    pub fn lua_tobuffer(L: *mut lua_State, idx: c_int, len: *mut usize) -> *mut c_void;
+    pub fn lua_topointer(L: *mut lua_State, idx: c_int) -> *const c_void;
+
+    //
+    // Push functions (C -> stack)
+    //
+    pub fn lua_pushnil(L: *mut lua_State);
+    pub fn lua_pushnumber(L: *mut lua_State, n: lua_Number);
+    #[link_name = "lua_pushinteger"]
+    pub fn lua_pushinteger_(L: *mut lua_State, n: c_int);
+    pub fn lua_pushunsigned(L: *mut lua_State, n: lua_Unsigned);
+    #[cfg(not(feature = "luau-vector4"))]
+    pub fn lua_pushvector(L: *mut lua_State, x: c_float, y: c_float, z: c_float);
+    #[cfg(feature = "luau-vector4")]
+    pub fn lua_pushvector(L: *mut lua_State, x: c_float, y: c_float, z: c_float, w: c_float);
+    #[link_name = "lua_pushlstring"]
+    pub fn lua_pushlstring_(L: *mut lua_State, s: *const c_char, l: usize);
+    #[link_name = "lua_pushstring"]
+    pub fn lua_pushstring_(L: *mut lua_State, s: *const c_char);
+    // lua_pushvfstring
+    #[link_name = "lua_pushfstringL"]
+    pub fn lua_pushfstring(L: *mut lua_State, fmt: *const c_char, ...) -> *const c_char;
+    pub fn lua_pushcclosurek(
+        L: *mut lua_State,
+        f: lua_CFunction,
+        debugname: *const c_char,
+        nup: c_int,
+        cont: Option<lua_Continuation>,
+    );
+    pub fn lua_pushboolean(L: *mut lua_State, b: c_int);
+    pub fn lua_pushthread(L: *mut lua_State) -> c_int;
+
+    pub fn lua_pushlightuserdatatagged(L: *mut lua_State, p: *mut c_void, tag: c_int);
+    pub fn lua_newuserdatatagged(L: *mut lua_State, sz: usize, tag: c_int) -> *mut c_void;
+    pub fn lua_newuserdatataggedwithmetatable(L: *mut lua_State, sz: usize, tag: c_int) -> *mut c_void;
+    pub fn lua_newuserdatadtor(L: *mut lua_State, sz: usize, dtor: lua_Destructor) -> *mut c_void;
+
+    pub fn lua_newbuffer(L: *mut lua_State, sz: usize) -> *mut c_void;
+
+    //
+    // Get functions (Lua -> stack)
+    //
+    pub fn lua_gettable(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_getfield(L: *mut lua_State, idx: c_int, k: *const c_char) -> c_int;
+    pub fn lua_rawgetfield(L: *mut lua_State, idx: c_int, k: *const c_char) -> c_int;
+    pub fn lua_rawget(L: *mut lua_State, idx: c_int) -> c_int;
+    #[link_name = "lua_rawgeti"]
+    pub fn lua_rawgeti_(L: *mut lua_State, idx: c_int, n: c_int) -> c_int;
+    pub fn lua_createtable(L: *mut lua_State, narr: c_int, nrec: c_int);
+
+    pub fn lua_setreadonly(L: *mut lua_State, idx: c_int, enabled: c_int);
+    pub fn lua_getreadonly(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_setsafeenv(L: *mut lua_State, idx: c_int, enabled: c_int);
+
+    pub fn lua_getmetatable(L: *mut lua_State, objindex: c_int) -> c_int;
+    pub fn lua_getfenv(L: *mut lua_State, idx: c_int);
+
+    //
+    // Set functions (stack -> Lua)
+    //
+    pub fn lua_settable(L: *mut lua_State, idx: c_int);
+    pub fn lua_setfield(L: *mut lua_State, idx: c_int, k: *const c_char);
+    pub fn lua_rawset(L: *mut lua_State, idx: c_int);
+    #[link_name = "lua_rawseti"]
+    pub fn lua_rawseti_(L: *mut lua_State, idx: c_int, n: c_int);
+    pub fn lua_setmetatable(L: *mut lua_State, objindex: c_int) -> c_int;
+    pub fn lua_setfenv(L: *mut lua_State, idx: c_int) -> c_int;
+
+    //
+    // `load' and `call' functions (load and run Luau bytecode)
+    //
+    pub fn luau_load(
+        L: *mut lua_State,
+        chunkname: *const c_char,
+        data: *const c_char,
+        size: usize,
+        env: c_int,
+    ) -> c_int;
+    pub fn lua_call(L: *mut lua_State, nargs: c_int, nresults: c_int);
+    pub fn lua_pcall(L: *mut lua_State, nargs: c_int, nresults: c_int, errfunc: c_int) -> c_int;
+    pub fn lua_cpcall(L: *mut lua_State, f: lua_CFunction, ud: *mut c_void) -> c_int;
+
+    //
+    // Coroutine functions
+    //
+    pub fn lua_yield(L: *mut lua_State, nresults: c_int) -> c_int;
+    pub fn lua_break(L: *mut lua_State) -> c_int;
+    #[link_name = "lua_resume"]
+    pub fn lua_resume_(L: *mut lua_State, from: *mut lua_State, narg: c_int) -> c_int;
+    pub fn lua_resumeerror(L: *mut lua_State, from: *mut lua_State) -> c_int;
+    pub fn lua_status(L: *mut lua_State) -> c_int;
+    pub fn lua_isyieldable(L: *mut lua_State) -> c_int;
+    pub fn lua_getthreaddata(L: *mut lua_State) -> *mut c_void;
+    pub fn lua_setthreaddata(L: *mut lua_State, data: *mut c_void);
+}
+
+//
+// Garbage-collection function and options
+//
+pub const LUA_GCSTOP: c_int = 0;
+pub const LUA_GCRESTART: c_int = 1;
+pub const LUA_GCCOLLECT: c_int = 2;
+pub const LUA_GCCOUNT: c_int = 3;
+pub const LUA_GCCOUNTB: c_int = 4;
+pub const LUA_GCISRUNNING: c_int = 5;
+pub const LUA_GCSTEP: c_int = 6;
+pub const LUA_GCSETGOAL: c_int = 7;
+pub const LUA_GCSETSTEPMUL: c_int = 8;
+pub const LUA_GCSETSTEPSIZE: c_int = 9;
+
+unsafe extern "C-unwind" {
+    pub fn lua_gc(L: *mut lua_State, what: c_int, data: c_int) -> c_int;
+}
+
+//
+// Memory statistics
+//
+unsafe extern "C-unwind" {
+    pub fn lua_setmemcat(L: *mut lua_State, category: c_int);
+    pub fn lua_totalbytes(L: *mut lua_State, category: c_int) -> usize;
+}
+
+//
+// Miscellaneous functions
+//
+unsafe extern "C-unwind" {
+    pub fn lua_error(L: *mut lua_State) -> !;
+    pub fn lua_next(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_rawiter(L: *mut lua_State, idx: c_int, iter: c_int) -> c_int;
+    pub fn lua_concat(L: *mut lua_State, n: c_int);
+    // TODO: lua_encodepointer
+    pub fn lua_clock() -> c_double;
+    pub fn lua_setuserdatatag(L: *mut lua_State, idx: c_int, tag: c_int);
+    pub fn lua_setuserdatadtor(L: *mut lua_State, tag: c_int, dtor: Option<lua_Destructor>);
+    pub fn lua_getuserdatadtor(L: *mut lua_State, tag: c_int) -> Option<lua_Destructor>;
+    pub fn lua_setuserdatametatable(L: *mut lua_State, tag: c_int);
+    pub fn lua_getuserdatametatable(L: *mut lua_State, tag: c_int);
+    pub fn lua_setlightuserdataname(L: *mut lua_State, tag: c_int, name: *const c_char);
+    pub fn lua_getlightuserdataname(L: *mut lua_State, tag: c_int) -> *const c_char;
+    pub fn lua_clonefunction(L: *mut lua_State, idx: c_int);
+    pub fn lua_cleartable(L: *mut lua_State, idx: c_int);
+    pub fn lua_getallocf(L: *mut lua_State, ud: *mut *mut c_void) -> lua_Alloc;
+}
+
+//
+// Reference system, can be used to pin objects
+//
+pub const LUA_NOREF: c_int = -1;
+pub const LUA_REFNIL: c_int = 0;
+
+unsafe extern "C-unwind" {
+    pub fn lua_ref(L: *mut lua_State, idx: c_int) -> c_int;
+    pub fn lua_unref(L: *mut lua_State, r#ref: c_int);
+}
+
+//
+// Some useful macros (implemented as Rust functions)
+//
+
+#[inline(always)]
+pub unsafe fn lua_tonumber(L: *mut lua_State, idx: c_int) -> lua_Number {
+    lua_tonumberx(L, idx, ptr::null_mut())
+}
+
+#[inline(always)]
+pub unsafe fn lua_tointeger_(L: *mut lua_State, idx: c_int) -> c_int {
+    lua_tointegerx_(L, idx, ptr::null_mut())
+}
+
+#[inline(always)]
+pub unsafe fn lua_tounsigned(L: *mut lua_State, i: c_int) -> lua_Unsigned {
+    lua_tounsignedx(L, i, ptr::null_mut())
+}
+
+#[inline(always)]
+pub unsafe fn lua_pop(L: *mut lua_State, n: c_int) {
+    lua_settop(L, -n - 1)
+}
+
+#[inline(always)]
+pub unsafe fn lua_newtable(L: *mut lua_State) {
+    lua_createtable(L, 0, 0)
+}
+
+#[inline(always)]
+pub unsafe fn lua_newuserdata(L: *mut lua_State, sz: usize) -> *mut c_void {
+    lua_newuserdatatagged(L, sz, 0)
+}
+
+#[inline(always)]
+pub unsafe fn lua_newuserdata_t<T>(L: *mut lua_State, data: T) -> *mut T {
+    unsafe extern "C" fn destructor<T>(_: *mut lua_State, ud: *mut c_void) {
+        ptr::drop_in_place(ud as *mut T);
+    }
+
+    let ud_ptr = lua_newuserdatadtor(L, const { mem::size_of::<T>() }, destructor::<T>) as *mut T;
+    ptr::write(ud_ptr, data);
+    ud_ptr
+}
+
+// TODO: lua_strlen
+
+#[inline(always)]
+pub unsafe fn lua_isfunction(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TFUNCTION) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_istable(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TTABLE) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_islightuserdata(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TLIGHTUSERDATA) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_isnil(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TNIL) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_isboolean(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TBOOLEAN) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_isvector(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TVECTOR) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_isthread(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TTHREAD) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_isbuffer(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TBUFFER) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_isnone(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) == LUA_TNONE) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_isnoneornil(L: *mut lua_State, n: c_int) -> c_int {
+    (lua_type(L, n) <= LUA_TNIL) as c_int
+}
+
+#[inline(always)]
+pub unsafe fn lua_pushliteral(L: *mut lua_State, s: &'static CStr) {
+    lua_pushstring_(L, s.as_ptr());
+}
+
+#[inline(always)]
+pub unsafe fn lua_pushcfunction(L: *mut lua_State, f: lua_CFunction) {
+    lua_pushcclosurek(L, f, ptr::null(), 0, None)
+}
+
+#[inline(always)]
+pub unsafe fn lua_pushcfunctiond(L: *mut lua_State, f: lua_CFunction, debugname: *const c_char) {
+    lua_pushcclosurek(L, f, debugname, 0, None)
+}
+
+#[inline(always)]
+pub unsafe fn lua_pushcclosure(L: *mut lua_State, f: lua_CFunction, nup: c_int) {
+    lua_pushcclosurek(L, f, ptr::null(), nup, None)
+}
+
+#[inline(always)]
+pub unsafe fn lua_pushcclosured(L: *mut lua_State, f: lua_CFunction, debugname: *const c_char, nup: c_int) {
+    lua_pushcclosurek(L, f, debugname, nup, None)
+}
+
+#[inline(always)]
+pub unsafe fn lua_pushlightuserdata(L: *mut lua_State, p: *mut c_void) {
+    lua_pushlightuserdatatagged(L, p, 0)
+}
+
+#[inline(always)]
+pub unsafe fn lua_setglobal(L: *mut lua_State, var: *const c_char) {
+    lua_setfield(L, LUA_GLOBALSINDEX, var)
+}
+
+#[inline(always)]
+pub unsafe fn lua_getglobal(L: *mut lua_State, var: *const c_char) -> c_int {
+    lua_getfield(L, LUA_GLOBALSINDEX, var)
+}
+
+#[inline(always)]
+pub unsafe fn lua_tostring(L: *mut lua_State, i: c_int) -> *const c_char {
+    lua_tolstring(L, i, ptr::null_mut())
+}
+
+//
+// Debug API
+//
+
+// Maximum size for the description of the source of a function in debug information.
+const LUA_IDSIZE: usize = 256;
+
+/// Type for functions to be called on debug events.
+pub type lua_Hook = unsafe extern "C-unwind" fn(L: *mut lua_State, ar: *mut lua_Debug);
+
+pub type lua_Coverage = unsafe extern "C-unwind" fn(
+    context: *mut c_void,
+    function: *const c_char,
+    linedefined: c_int,
+    depth: c_int,
+    hits: *const c_int,
+    size: usize,
+);
+
+unsafe extern "C-unwind" {
+    pub fn lua_stackdepth(L: *mut lua_State) -> c_int;
+    pub fn lua_getinfo(L: *mut lua_State, level: c_int, what: *const c_char, ar: *mut lua_Debug) -> c_int;
+    pub fn lua_getargument(L: *mut lua_State, level: c_int, n: c_int) -> c_int;
+    pub fn lua_getlocal(L: *mut lua_State, level: c_int, n: c_int) -> *const c_char;
+    pub fn lua_setlocal(L: *mut lua_State, level: c_int, n: c_int) -> *const c_char;
+    pub fn lua_getupvalue(L: *mut lua_State, funcindex: c_int, n: c_int) -> *const c_char;
+    pub fn lua_setupvalue(L: *mut lua_State, funcindex: c_int, n: c_int) -> *const c_char;
+
+    pub fn lua_singlestep(L: *mut lua_State, enabled: c_int);
+    pub fn lua_breakpoint(L: *mut lua_State, funcindex: c_int, line: c_int, enabled: c_int) -> c_int;
+
+    pub fn lua_getcoverage(L: *mut lua_State, funcindex: c_int, context: *mut c_void, callback: lua_Coverage);
+
+    pub fn lua_debugtrace(L: *mut lua_State) -> *const c_char;
+}
+
+#[repr(C)]
+pub struct lua_Debug {
+    pub name: *const c_char,
+    pub what: *const c_char,
+    pub source: *const c_char,
+    pub short_src: *const c_char,
+    pub linedefined: c_int,
+    pub currentline: c_int,
+    pub nupvals: u8,
+    pub nparams: u8,
+    pub isvararg: c_char,
+    pub userdata: *mut c_void,
+    pub ssbuf: [c_char; LUA_IDSIZE],
+}
+
+//
+// Callbacks that can be used to reconfigure behavior of the VM dynamically.
+// These are shared between all coroutines.
+//
+
+#[repr(C)]
+#[non_exhaustive]
+pub struct lua_Callbacks {
+    /// arbitrary userdata pointer that is never overwritten by Luau
+    pub userdata: *mut c_void,
+
+    /// gets called at safepoints (loop back edges, call/ret, gc) if set
+    pub interrupt: Option<unsafe extern "C-unwind" fn(L: *mut lua_State, gc: c_int)>,
+    /// gets called when an unprotected error is raised (if longjmp is used)
+    pub panic: Option<unsafe extern "C-unwind" fn(L: *mut lua_State, errcode: c_int)>,
+
+    /// gets called when L is created (LP == parent) or destroyed (LP == NULL)
+    pub userthread: Option<unsafe extern "C-unwind" fn(LP: *mut lua_State, L: *mut lua_State)>,
+    /// gets called when a string is created; returned atom can be retrieved via tostringatom
+    pub useratom: Option<unsafe extern "C-unwind" fn(s: *const c_char, l: usize) -> i16>,
+
+    /// gets called when BREAK instruction is encountered
+    pub debugbreak: Option<unsafe extern "C-unwind" fn(L: *mut lua_State, ar: *mut lua_Debug)>,
+    /// gets called after each instruction in single step mode
+    pub debugstep: Option<unsafe extern "C-unwind" fn(L: *mut lua_State, ar: *mut lua_Debug)>,
+    /// gets called when thread execution is interrupted by break in another thread
+    pub debuginterrupt: Option<unsafe extern "C-unwind" fn(L: *mut lua_State, ar: *mut lua_Debug)>,
+    /// gets called when protected call results in an error
+    pub debugprotectederror: Option<unsafe extern "C-unwind" fn(L: *mut lua_State)>,
+
+    /// gets called when memory is allocated
+    pub onallocate: Option<unsafe extern "C-unwind" fn(L: *mut lua_State, osize: usize, nsize: usize)>,
+}
+
+unsafe extern "C" {
+    pub fn lua_callbacks(L: *mut lua_State) -> *mut lua_Callbacks;
+}
+
+// Functions from customization lib
+unsafe extern "C" {
+    pub fn luau_setfflag(name: *const c_char, value: c_int) -> c_int;
+    pub fn lua_getmetatablepointer(L: *mut lua_State, idx: c_int) -> *const c_void;
+}

mlua-sys/src/luau/luacode.rs

@@ -0,0 +1,113 @@
+//! Contains definitions from `luacode.h`.
+
+use std::marker::{PhantomData, PhantomPinned};
+use std::os::raw::{c_char, c_int, c_void};
+use std::{ptr, slice};
+
+#[repr(C)]
+#[non_exhaustive]
+pub struct lua_CompileOptions {
+    pub optimizationLevel: c_int,
+    pub debugLevel: c_int,
+    pub typeInfoLevel: c_int,
+    pub coverageLevel: c_int,
+    pub vectorLib: *const c_char,
+    pub vectorCtor: *const c_char,
+    pub vectorType: *const c_char,
+    pub mutableGlobals: *const *const c_char,
+    pub userdataTypes: *const *const c_char,
+    pub librariesWithKnownMembers: *const *const c_char,
+    pub libraryMemberTypeCallback: Option<lua_LibraryMemberTypeCallback>,
+    pub libraryMemberConstantCallback: Option<lua_LibraryMemberConstantCallback>,
+    pub disabledBuiltins: *const *const c_char,
+}
+
+impl Default for lua_CompileOptions {
+    fn default() -> Self {
+        Self {
+            optimizationLevel: 1,
+            debugLevel: 1,
+            typeInfoLevel: 0,
+            coverageLevel: 0,
+            vectorLib: ptr::null(),
+            vectorCtor: ptr::null(),
+            vectorType: ptr::null(),
+            mutableGlobals: ptr::null(),
+            userdataTypes: ptr::null(),
+            librariesWithKnownMembers: ptr::null(),
+            libraryMemberTypeCallback: None,
+            libraryMemberConstantCallback: None,
+            disabledBuiltins: ptr::null(),
+        }
+    }
+}
+
+#[repr(C)]
+pub struct lua_CompileConstant {
+    _data: [u8; 0],
+    _marker: PhantomData<(*mut u8, PhantomPinned)>,
+}
+
+/// Type table tags
+#[doc(hidden)]
+#[repr(i32)]
+#[non_exhaustive]
+pub enum luau_BytecodeType {
+    Nil = 0,
+    Boolean,
+    Number,
+    String,
+    Table,
+    Function,
+    Thread,
+    UserData,
+    Vector,
+    Buffer,
+
+    Any = 15,
+}
+
+pub type lua_LibraryMemberTypeCallback =
+    unsafe extern "C-unwind" fn(library: *const c_char, member: *const c_char) -> c_int;
+
+pub type lua_LibraryMemberConstantCallback = unsafe extern "C-unwind" fn(
+    library: *const c_char,
+    member: *const c_char,
+    constant: *mut lua_CompileConstant,
+);
+
+unsafe extern "C" {
+    pub fn luau_set_compile_constant_nil(cons: *mut lua_CompileConstant);
+    pub fn luau_set_compile_constant_boolean(cons: *mut lua_CompileConstant, b: c_int);
+    pub fn luau_set_compile_constant_number(cons: *mut lua_CompileConstant, n: f64);
+    pub fn luau_set_compile_constant_vector(cons: *mut lua_CompileConstant, x: f32, y: f32, z: f32, w: f32);
+    pub fn luau_set_compile_constant_string(cons: *mut lua_CompileConstant, s: *const c_char, l: usize);
+}
+
+unsafe extern "C-unwind" {
+    #[link_name = "luau_compile"]
+    pub fn luau_compile_(
+        source: *const c_char,
+        size: usize,
+        options: *mut lua_CompileOptions,
+        outsize: *mut usize,
+    ) -> *mut c_char;
+}
+
+unsafe extern "C" {
+    fn free(p: *mut c_void);
+}
+
+pub unsafe fn luau_compile(source: &[u8], mut options: lua_CompileOptions) -> Vec<u8> {
+    let mut outsize = 0;
+    let data_ptr = luau_compile_(
+        source.as_ptr() as *const c_char,
+        source.len(),
+        &mut options,
+        &mut outsize,
+    );
+    assert!(!data_ptr.is_null(), "luau_compile failed");
+    let data = slice::from_raw_parts(data_ptr as *mut u8, outsize).to_vec();
+    free(data_ptr as *mut c_void);
+    data
+}

mlua-sys/src/luau/luacodegen.rs

@@ -0,0 +1,11 @@
+//! Contains definitions from `luacodegen.h`.
+
+use std::os::raw::c_int;
+
+use super::lua::lua_State;
+
+unsafe extern "C-unwind" {
+    pub fn luau_codegen_supported() -> c_int;
+    pub fn luau_codegen_create(state: *mut lua_State);
+    pub fn luau_codegen_compile(state: *mut lua_State, idx: c_int);
+}

mlua-sys/src/luau/lualib.rs

@@ -0,0 +1,33 @@
+//! Contains definitions from `lualib.h`.
+
+use std::os::raw::{c_char, c_int};
+
+use super::lua::lua_State;
+
+pub const LUA_COLIBNAME: *const c_char = cstr!("coroutine");
+pub const LUA_TABLIBNAME: *const c_char = cstr!("table");
+pub const LUA_OSLIBNAME: *const c_char = cstr!("os");
+pub const LUA_STRLIBNAME: *const c_char = cstr!("string");
+pub const LUA_BITLIBNAME: *const c_char = cstr!("bit32");
+pub const LUA_BUFFERLIBNAME: *const c_char = cstr!("buffer");
+pub const LUA_UTF8LIBNAME: *const c_char = cstr!("utf8");
+pub const LUA_MATHLIBNAME: *const c_char = cstr!("math");
+pub const LUA_DBLIBNAME: *const c_char = cstr!("debug");
+pub const LUA_VECLIBNAME: *const c_char = cstr!("vector");
+
+unsafe extern "C-unwind" {
+    pub fn luaopen_base(L: *mut lua_State) -> c_int;
+    pub fn luaopen_coroutine(L: *mut lua_State) -> c_int;
+    pub fn luaopen_table(L: *mut lua_State) -> c_int;
+    pub fn luaopen_os(L: *mut lua_State) -> c_int;
+    pub fn luaopen_string(L: *mut lua_State) -> c_int;
+    pub fn luaopen_bit32(L: *mut lua_State) -> c_int;
+    pub fn luaopen_buffer(L: *mut lua_State) -> c_int;
+    pub fn luaopen_utf8(L: *mut lua_State) -> c_int;
+    pub fn luaopen_math(L: *mut lua_State) -> c_int;
+    pub fn luaopen_debug(L: *mut lua_State) -> c_int;
+    pub fn luaopen_vector(L: *mut lua_State) -> c_int;
+
+    // open all builtin libraries
+    pub fn luaL_openlibs(L: *mut lua_State);
+}

mlua-sys/src/luau/luarequire.rs

@@ -0,0 +1,177 @@
+//! Contains definitions from `Require.h`.
+
+use std::os::raw::{c_char, c_int, c_void};
+
+use super::lua::lua_State;
+
+pub const LUA_REGISTERED_MODULES_TABLE: *const c_char = cstr!("_REGISTEREDMODULES");
+
+#[repr(C)]
+pub enum luarequire_NavigateResult {
+    Success,
+    Ambiguous,
+    NotFound,
+}
+
+// Functions returning WriteSuccess are expected to set their size_out argument
+// to the number of bytes written to the buffer. If WriteBufferTooSmall is
+// returned, size_out should be set to the required buffer size.
+#[repr(C)]
+pub enum luarequire_WriteResult {
+    Success,
+    BufferTooSmall,
+    Failure,
+}
+
+#[repr(C)]
+pub struct luarequire_Configuration {
+    // Returns whether requires are permitted from the given chunkname.
+    pub is_require_allowed: unsafe extern "C-unwind" fn(
+        L: *mut lua_State,
+        ctx: *mut c_void,
+        requirer_chunkname: *const c_char,
+    ) -> bool,
+
+    // Resets the internal state to point at the requirer module.
+    pub reset: unsafe extern "C-unwind" fn(
+        L: *mut lua_State,
+        ctx: *mut c_void,
+        requirer_chunkname: *const c_char,
+    ) -> luarequire_NavigateResult,
+
+    // Resets the internal state to point at an aliased module, given its exact path from a configuration
+    // file. This function is only called when an alias's path cannot be resolved relative to its
+    // configuration file.
+    pub jump_to_alias: unsafe extern "C-unwind" fn(
+        L: *mut lua_State,
+        ctx: *mut c_void,
+        path: *const c_char,
+    ) -> luarequire_NavigateResult,
+
+    // Navigates through the context by making mutations to the internal state.
+    pub to_parent:
+        unsafe extern "C-unwind" fn(L: *mut lua_State, ctx: *mut c_void) -> luarequire_NavigateResult,
+    pub to_child: unsafe extern "C-unwind" fn(
+        L: *mut lua_State,
+        ctx: *mut c_void,
+        name: *const c_char,
+    ) -> luarequire_NavigateResult,
+
+    // Returns whether the context is currently pointing at a module.
+    pub is_module_present: unsafe extern "C-unwind" fn(L: *mut lua_State, ctx: *mut c_void) -> bool,
+
+    // Provides a chunkname for the current module. This will be accessible through the debug library. This
+    // function is only called if is_module_present returns true.
+    pub get_chunkname: unsafe extern "C-unwind" fn(
+        L: *mut lua_State,
+        ctx: *mut c_void,
+        buffer: *mut c_char,
+        buffer_size: usize,
+        size_out: *mut usize,
+    ) -> luarequire_WriteResult,
+
+    // Provides a loadname that identifies the current module and is passed to load. This function
+    // is only called if is_module_present returns true.
+    pub get_loadname: unsafe extern "C-unwind" fn(
+        L: *mut lua_State,
+        ctx: *mut c_void,
+        buffer: *mut c_char,
+        buffer_size: usize,
+        size_out: *mut usize,
+    ) -> luarequire_WriteResult,
+
+    // Provides a cache key representing the current module. This function is only called if
+    // is_module_present returns true.
+    pub get_cache_key: unsafe extern "C-unwind" fn(
+        L: *mut lua_State,
+        ctx: *mut c_void,
+        buffer: *mut c_char,
+        buffer_size: usize,
+        size_out: *mut usize,
+    ) -> luarequire_WriteResult,
+
+    // Returns whether a configuration file is present in the current context.
+    // If not, require-by-string will call to_parent until either a configuration file is present or
+    // NAVIGATE_FAILURE is returned (at root).
+    pub is_config_present: unsafe extern "C-unwind" fn(L: *mut lua_State, ctx: *mut c_void) -> bool,
+
+    // Parses the configuration file in the current context for the given alias and returns its
+    // value or WRITE_FAILURE if not found. This function is only called if is_config_present
+    // returns true. If this function pointer is set, get_config must not be set. Opting in to this
+    // function pointer disables parsing configuration files internally and can be used for finer
+    // control over the configuration file parsing process.
+    pub get_alias: Option<
+        unsafe extern "C-unwind" fn(
+            L: *mut lua_State,
+            ctx: *mut c_void,
+            alias: *const c_char,
+            buffer: *mut c_char,
+            buffer_size: usize,
+            size_out: *mut usize,
+        ) -> luarequire_WriteResult,
+    >,
+
+    // Provides the contents of the configuration file in the current context. This function is only called
+    // if is_config_present returns true. If this function pointer is set, get_alias must not be set. Opting
+    // in to this function pointer enables parsing configuration files internally.
+    pub get_config: Option<
+        unsafe extern "C-unwind" fn(
+            L: *mut lua_State,
+            ctx: *mut c_void,
+            buffer: *mut c_char,
+            buffer_size: usize,
+            size_out: *mut usize,
+        ) -> luarequire_WriteResult,
+    >,
+
+    // Executes the module and places the result on the stack. Returns the number of results placed on the
+    // stack.
+    // Returning -1 directs the requiring thread to yield. In this case, this thread should be resumed with
+    // the module result pushed onto its stack.
+    pub load: unsafe extern "C-unwind" fn(
+        L: *mut lua_State,
+        ctx: *mut c_void,
+        path: *const c_char,
+        chunkname: *const c_char,
+        loadname: *const c_char,
+    ) -> c_int,
+}
+
+// Populates function pointers in the given luarequire_Configuration.
+pub type luarequire_Configuration_init = unsafe extern "C-unwind" fn(config: *mut luarequire_Configuration);
+
+unsafe extern "C-unwind" {
+    // Initializes and pushes the require closure onto the stack without registration.
+    pub fn luarequire_pushrequire(
+        L: *mut lua_State,
+        config_init: luarequire_Configuration_init,
+        ctx: *mut c_void,
+    ) -> c_int;
+
+    // Initializes the require library and registers it globally.
+    pub fn luaopen_require(L: *mut lua_State, config_init: luarequire_Configuration_init, ctx: *mut c_void);
+
+    // Initializes and pushes a "proxyrequire" closure onto the stack.
+    //
+    // The closure takes two parameters: the string path to resolve and the chunkname of an existing
+    // module.
+    pub fn luarequire_pushproxyrequire(
+        L: *mut lua_State,
+        config_init: luarequire_Configuration_init,
+        ctx: *mut c_void,
+    ) -> c_int;
+
+    // Registers an aliased require path to a result.
+    //
+    // After registration, the given result will always be immediately returned when the given path is
+    // required.
+    // Expects the path and table to be passed as arguments on the stack.
+    pub fn luarequire_registermodule(L: *mut lua_State) -> c_int;
+
+    // Clears the entry associated with the given cache key from the require cache.
+    // Expects the cache key to be passed as an argument on the stack.
+    pub fn luarequire_clearcacheentry(L: *mut lua_State) -> c_int;
+
+    // Clears all entries from the require cache.
+    pub fn luarequire_clearcache(L: *mut lua_State) -> c_int;
+}

mlua-sys/src/luau/mod.rs

@@ -0,0 +1,17 @@
+//! Low level bindings to Luau.
+
+pub use compat::*;
+pub use lauxlib::*;
+pub use lua::*;
+pub use luacode::*;
+pub use luacodegen::*;
+pub use lualib::*;
+pub use luarequire::*;
+
+pub mod compat;
+pub mod lauxlib;
+pub mod lua;
+pub mod luacode;
+pub mod luacodegen;
+pub mod lualib;
+pub mod luarequire;

mlua-sys/src/macros.rs

@@ -0,0 +1,6 @@
+#[allow(unused_macros)]
+macro_rules! cstr {
+    ($s:expr) => {
+        concat!($s, "\0") as *const str as *const [::std::os::raw::c_char] as *const ::std::os::raw::c_char
+    };
+}

mlua_derive/Cargo.toml

@@ -1,17 +1,24 @@
 [package]
 name = "mlua_derive"
-version = "0.2.0"
-authors = ["Aleksandr Orlenko <zxteam@protonmail.com>"]
-edition = "2018"
+version = "0.11.0"
+authors = ["Aleksandr Orlenko <zxteam@pm.me>"]
+edition = "2021"
 description = "Procedural macros for the mlua crate."
-repository = "https://github.com/khvzak/mlua"
+repository = "https://github.com/mlua-rs/mlua"
 keywords = ["lua", "mlua"]
 license = "MIT"
 
 [lib]
 proc-macro = true
 
+[features]
+macros = ["proc-macro-error2", "itertools", "regex", "once_cell"]
+
 [dependencies]
-proc-macro2 = "1.0"
 quote = "1.0"
-syn = { version = "1.0", features = ["full"] }
+proc-macro2 = { version = "1.0", features = ["span-locations"] }
+proc-macro-error2 = { version = "2.0.1", optional = true }
+syn = { version = "2.0", features = ["full"] }
+itertools = { version = "0.14", optional = true }
+regex = { version = "1.4", optional = true }
+once_cell = { version = "1.0", optional = true }

mlua_derive/src/chunk.rs

@@ -0,0 +1,105 @@
+use proc_macro::{TokenStream, TokenTree};
+
+use crate::token::{Pos, Token, Tokens};
+
+#[derive(Debug, Clone)]
+pub(crate) struct Capture {
+    key: Token,
+    rust: TokenTree,
+}
+
+impl Capture {
+    fn new(key: Token, rust: TokenTree) -> Self {
+        Self { key, rust }
+    }
+
+    /// Token string inside `chunk!`
+    pub(crate) fn key(&self) -> &Token {
+        &self.key
+    }
+
+    /// As rust variable, e.g. `x`
+    pub(crate) fn as_rust(&self) -> &TokenTree {
+        &self.rust
+    }
+}
+
+#[derive(Debug)]
+pub(crate) struct Captures(Vec<Capture>);
+
+impl Captures {
+    pub(crate) fn new() -> Self {
+        Self(Vec::new())
+    }
+
+    pub(crate) fn add(&mut self, token: &Token) -> Capture {
+        let tt = token.tree();
+        let key = token.clone();
+
+        match self.0.iter().find(|arg| arg.key() == &key) {
+            Some(arg) => arg.clone(),
+            None => {
+                let arg = Capture::new(key, tt.clone());
+                self.0.push(arg.clone());
+                arg
+            }
+        }
+    }
+
+    pub(crate) fn captures(&self) -> &[Capture] {
+        &self.0
+    }
+}
+
+#[derive(Debug)]
+pub(crate) struct Chunk {
+    source: String,
+    caps: Captures,
+}
+
+impl Chunk {
+    pub(crate) fn new(tokens: TokenStream) -> Self {
+        let tokens = Tokens::retokenize(tokens);
+
+        let mut source = String::new();
+        let mut caps = Captures::new();
+
+        let mut pos: Option<Pos> = None;
+        for t in tokens {
+            if t.is_cap() {
+                caps.add(&t);
+            }
+
+            let (line, col) = (t.start().line, t.start().column);
+            let (prev_line, prev_col) = pos
+                .take()
+                .map(|lc| (lc.line, lc.column))
+                .unwrap_or_else(|| (line, col));
+
+            #[allow(clippy::comparison_chain)]
+            if line > prev_line {
+                source.push('\n');
+            } else if line == prev_line {
+                for _ in 0..col.saturating_sub(prev_col) {
+                    source.push(' ');
+                }
+            }
+            source.push_str(&t.to_string());
+
+            pos = Some(t.end());
+        }
+
+        Self {
+            source: source.trim_end().to_string(),
+            caps,
+        }
+    }
+
+    pub(crate) fn source(&self) -> &str {
+        &self.source
+    }
+
+    pub(crate) fn captures(&self) -> &[Capture] {
+        self.caps.captures()
+    }
+}

mlua_derive/src/from_lua.rs

@@ -0,0 +1,31 @@
+use proc_macro::TokenStream;
+use quote::quote;
+use syn::{parse_macro_input, DeriveInput};
+
+pub fn from_lua(input: TokenStream) -> TokenStream {
+    let DeriveInput { ident, generics, .. } = parse_macro_input!(input as DeriveInput);
+
+    let ident_str = ident.to_string();
+    let (impl_generics, ty_generics, _) = generics.split_for_impl();
+    let where_clause = match &generics.where_clause {
+        Some(where_clause) => quote! { #where_clause, Self: 'static + Clone },
+        None => quote! { where Self: 'static + Clone },
+    };
+
+    quote! {
+      impl #impl_generics ::mlua::FromLua for #ident #ty_generics #where_clause {
+        #[inline]
+        fn from_lua(value: ::mlua::Value, _: &::mlua::Lua) -> ::mlua::Result<Self> {
+          match value {
+            ::mlua::Value::UserData(ud) => Ok(ud.borrow::<Self>()?.clone()),
+            _ => Err(::mlua::Error::FromLuaConversionError {
+                from: value.type_name(),
+                to: #ident_str.to_string(),
+                message: None,
+            }),
+          }
+        }
+      }
+    }
+    .into()
+}

mlua_derive/src/lib.rs

@@ -1,35 +1,159 @@
-extern crate proc_macro;
-
 use proc_macro::TokenStream;
 use proc_macro2::{Ident, Span};
-use quote::quote_spanned;
-use syn::{parse_macro_input, spanned::Spanned, AttributeArgs, Error, ItemFn};
+use quote::quote;
+use syn::meta::ParseNestedMeta;
+use syn::{parse_macro_input, ItemFn, LitStr, Result};
+
+#[cfg(feature = "macros")]
+use {
+    crate::chunk::Chunk, proc_macro::TokenTree, proc_macro2::TokenStream as TokenStream2,
+    proc_macro_error2::proc_macro_error,
+};
+
+#[derive(Default)]
+struct ModuleAttributes {
+    name: Option<Ident>,
+    skip_memory_check: bool,
+}
+
+impl ModuleAttributes {
+    fn parse(&mut self, meta: ParseNestedMeta) -> Result<()> {
+        if meta.path.is_ident("name") {
+            match meta.value() {
+                Ok(value) => {
+                    self.name = Some(value.parse::<LitStr>()?.parse()?);
+                }
+                Err(_) => {
+                    return Err(meta.error("`name` attribute must have a value"));
+                }
+            }
+        } else if meta.path.is_ident("skip_memory_check") {
+            if meta.value().is_ok() {
+                return Err(meta.error("`skip_memory_check` attribute have no values"));
+            }
+            self.skip_memory_check = true;
+        } else {
+            return Err(meta.error("unsupported module attribute"));
+        }
+        Ok(())
+    }
+}
 
 #[proc_macro_attribute]
 pub fn lua_module(attr: TokenStream, item: TokenStream) -> TokenStream {
-    let args = parse_macro_input!(attr as AttributeArgs);
-    let item = parse_macro_input!(item as ItemFn);
-
-    if args.len() > 0 {
-        let err = Error::new(Span::call_site(), "the number of arguments must be zero")
-            .to_compile_error();
-        return err.into();
+    let mut args = ModuleAttributes::default();
+    if !attr.is_empty() {
+        let args_parser = syn::meta::parser(|meta| args.parse(meta));
+        parse_macro_input!(attr with args_parser);
     }
 
-    let span = item.span();
-    let item_name = item.sig.ident.clone();
-    let ext_entrypoint_name = Ident::new(&format!("luaopen_{}", item.sig.ident), Span::call_site());
+    let func = parse_macro_input!(item as ItemFn);
+    let func_name = &func.sig.ident;
+    let module_name = args.name.unwrap_or_else(|| func_name.clone());
+    let ext_entrypoint_name = Ident::new(&format!("luaopen_{module_name}"), Span::call_site());
+    let skip_memory_check = if args.skip_memory_check {
+        quote! { lua.skip_memory_check(true); }
+    } else {
+        quote! {}
+    };
+
+    let wrapped = quote! {
+        mlua::require_module_feature!();
+
+        #func
 
-    let wrapped = quote_spanned! { span =>
         #[no_mangle]
-        unsafe extern "C" fn #ext_entrypoint_name(state: *mut mlua::lua_State) -> std::os::raw::c_int {
-            #item
-
-            mlua::Lua::init_from_ptr(state)
-                .entrypoint1(#item_name)
-                .unwrap()
+        unsafe extern "C-unwind" fn #ext_entrypoint_name(state: *mut mlua::lua_State) -> ::std::os::raw::c_int {
+            mlua::Lua::entrypoint1(state, move |lua| {
+                #skip_memory_check
+                #func_name(lua)
+            })
         }
     };
 
     wrapped.into()
 }
+
+#[cfg(feature = "macros")]
+fn to_ident(tt: &TokenTree) -> TokenStream2 {
+    let s: TokenStream = tt.clone().into();
+    s.into()
+}
+
+#[cfg(feature = "macros")]
+#[proc_macro]
+#[proc_macro_error]
+pub fn chunk(input: TokenStream) -> TokenStream {
+    let chunk = Chunk::new(input);
+
+    let source = chunk.source();
+
+    let caps_len = chunk.captures().len();
+    let caps = chunk.captures().iter().map(|cap| {
+        let cap_name = cap.as_rust().to_string();
+        let cap = to_ident(cap.as_rust());
+        quote! { env.raw_set(#cap_name, #cap)?; }
+    });
+
+    let wrapped_code = quote! {{
+        use mlua::{AsChunk, ChunkMode, Lua, Result, Table};
+        use ::std::borrow::Cow;
+        use ::std::cell::Cell;
+        use ::std::io::Result as IoResult;
+
+        struct InnerChunk<F: FnOnce(&Lua) -> Result<Table>>(Cell<Option<F>>);
+
+        impl<F> AsChunk for InnerChunk<F>
+        where
+            F: FnOnce(&Lua) -> Result<Table>,
+        {
+            fn environment(&self, lua: &Lua) -> Result<Option<Table>> {
+                if #caps_len > 0 {
+                    if let Some(make_env) = self.0.take() {
+                        return make_env(lua).map(Some);
+                    }
+                }
+                Ok(None)
+            }
+
+            fn mode(&self) -> Option<ChunkMode> {
+                Some(ChunkMode::Text)
+            }
+
+            fn source<'a>(&self) -> IoResult<Cow<'a, [u8]>> {
+                Ok(Cow::Borrowed((#source).as_bytes()))
+            }
+        }
+
+        let make_env = move |lua: &Lua| -> Result<Table> {
+            let globals = lua.globals();
+            let env = lua.create_table()?;
+            let meta = lua.create_table()?;
+            meta.raw_set("__index", &globals)?;
+            meta.raw_set("__newindex", &globals)?;
+
+            // Add captured variables
+            #(#caps)*
+
+            env.set_metatable(Some(meta))?;
+            Ok(env)
+        };
+
+        InnerChunk(Cell::new(Some(make_env)))
+    }};
+
+    wrapped_code.into()
+}
+
+#[cfg(feature = "macros")]
+#[proc_macro_derive(FromLua)]
+pub fn from_lua(input: TokenStream) -> TokenStream {
+    from_lua::from_lua(input)
+}
+
+#[cfg(feature = "macros")]
+mod chunk;
+#[cfg(feature = "macros")]
+mod from_lua;
+#[cfg(feature = "macros")]
+mod token;

mlua_derive/src/token.rs

@@ -0,0 +1,225 @@
+use std::cmp::{Eq, PartialEq};
+use std::fmt::{self, Display, Formatter};
+use std::vec::IntoIter;
+
+use itertools::Itertools;
+use once_cell::sync::Lazy;
+use proc_macro::{Delimiter, Span, TokenStream, TokenTree};
+use proc_macro2::Span as Span2;
+use regex::Regex;
+
+#[derive(Clone, Copy, Debug)]
+pub(crate) struct Pos {
+    pub(crate) line: usize,
+    pub(crate) column: usize,
+}
+
+impl Pos {
+    fn new(line: usize, column: usize) -> Self {
+        Self { line, column }
+    }
+
+    fn left(&self) -> Self {
+        Self {
+            line: self.line,
+            column: self.column.saturating_sub(1),
+        }
+    }
+
+    fn right(&self) -> Self {
+        Self {
+            line: self.line,
+            column: self.column.saturating_add(1),
+        }
+    }
+}
+
+fn span_pos(span: &Span) -> (Pos, Pos) {
+    let span2: Span2 = (*span).into();
+    let start = span2.start();
+    let end = span2.end();
+
+    // In stable, line/column information is not provided
+    // and set to 0 (line is 1-indexed)
+    if start.line == 0 || end.line == 0 {
+        return fallback_span_pos(span);
+    }
+
+    (Pos::new(start.line, start.column), Pos::new(end.line, end.column))
+}
+
+fn parse_pos(span: &Span) -> Option<(usize, usize)> {
+    // Workaround to somehow retrieve location information in span in stable rust :(
+
+    static RE: Lazy<Regex> = Lazy::new(|| Regex::new(r"bytes\(([0-9]+)\.\.([0-9]+)\)").unwrap());
+
+    match RE.captures(&format!("{span:?}")) {
+        Some(caps) => match (caps.get(1), caps.get(2)) {
+            (Some(start), Some(end)) => Some((
+                match start.as_str().parse() {
+                    Ok(v) => v,
+                    _ => return None,
+                },
+                match end.as_str().parse() {
+                    Ok(v) => v,
+                    _ => return None,
+                },
+            )),
+            _ => None,
+        },
+        None => None,
+    }
+}
+
+fn fallback_span_pos(span: &Span) -> (Pos, Pos) {
+    let (start, end) = match parse_pos(span) {
+        Some(v) => v,
+        None => proc_macro_error2::abort_call_site!("Cannot retrieve span information; please use nightly"),
+    };
+    (Pos::new(1, start), Pos::new(1, end))
+}
+
+/// Attribute of token.
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+enum TokenAttr {
+    /// No attribute
+    None,
+    /// Starts with `$`
+    Cap,
+}
+
+#[derive(Clone, Debug)]
+pub(crate) struct Token {
+    source: String,
+    tree: TokenTree,
+    start: Pos,
+    end: Pos,
+    attr: TokenAttr,
+}
+
+impl PartialEq for Token {
+    fn eq(&self, other: &Self) -> bool {
+        self.source == other.source && self.attr == other.attr
+    }
+}
+
+impl Eq for Token {}
+
+impl Token {
+    fn new(tree: TokenTree) -> Self {
+        let (start, end) = span_pos(&tree.span());
+        Self {
+            source: tree.to_string(),
+            start,
+            end,
+            tree,
+            attr: TokenAttr::None,
+        }
+    }
+
+    fn new_delim(source: String, tree: TokenTree, open: bool) -> Self {
+        let (start, end) = span_pos(&tree.span());
+        let (start, end) = if open {
+            (start, start.right())
+        } else {
+            (end.left(), end)
+        };
+
+        Self {
+            source,
+            tree,
+            start,
+            end,
+            attr: TokenAttr::None,
+        }
+    }
+
+    pub(crate) fn tree(&self) -> &TokenTree {
+        &self.tree
+    }
+
+    pub(crate) fn is_cap(&self) -> bool {
+        self.attr == TokenAttr::Cap
+    }
+
+    pub(crate) fn start(&self) -> Pos {
+        self.start
+    }
+
+    pub(crate) fn end(&self) -> Pos {
+        self.end
+    }
+
+    fn is(&self, s: &str) -> bool {
+        self.source == s
+    }
+
+    fn attr(mut self, attr: TokenAttr) -> Self {
+        self.attr = attr;
+        self
+    }
+}
+
+#[derive(Debug)]
+pub(crate) struct Tokens(pub(crate) Vec<Token>);
+
+impl Tokens {
+    pub(crate) fn retokenize(tt: TokenStream) -> Tokens {
+        Tokens(
+            tt.into_iter()
+                .flat_map(Tokens::from)
+                .peekable()
+                .batching(|iter| {
+                    // Find variable tokens
+                    let t = iter.next()?;
+                    if t.is("$") {
+                        // `$` + `ident` => `$ident`
+                        let t = iter.next().expect("$ must trail an identifier");
+                        Some(t.attr(TokenAttr::Cap))
+                    } else {
+                        Some(t)
+                    }
+                })
+                .collect(),
+        )
+    }
+}
+
+impl IntoIterator for Tokens {
+    type Item = Token;
+    type IntoIter = IntoIter<Token>;
+
+    fn into_iter(self) -> Self::IntoIter {
+        self.0.into_iter()
+    }
+}
+
+impl From<TokenTree> for Tokens {
+    fn from(tt: TokenTree) -> Self {
+        let tts = match tt.clone() {
+            TokenTree::Group(g) => {
+                let (b, e) = match g.delimiter() {
+                    Delimiter::Parenthesis => ("(", ")"),
+                    Delimiter::Brace => ("{", "}"),
+                    Delimiter::Bracket => ("[", "]"),
+                    Delimiter::None => ("", ""),
+                };
+                let (b, e) = (b.into(), e.into());
+
+                vec![Token::new_delim(b, tt.clone(), true)]
+                    .into_iter()
+                    .chain(g.stream().into_iter().flat_map(Tokens::from))
+                    .chain(vec![Token::new_delim(e, tt, false)])
+                    .collect()
+            }
+            _ => vec![Token::new(tt)],
+        };
+        Tokens(tts)
+    }
+}
+
+impl Display for Token {
+    fn fmt(&self, f: &mut Formatter) -> fmt::Result {
+        write!(f, "{}", self.source)
+    }
+}

rustfmt.toml

@@ -0,0 +1,4 @@
+imports_granularity = "Module"
+max_width = 110
+comment_width = 100
+wrap_comments = true

src/buffer.rs

@@ -0,0 +1,167 @@
+use std::io;
+
+#[cfg(feature = "serde")]
+use serde::ser::{Serialize, Serializer};
+
+use crate::state::RawLua;
+use crate::types::ValueRef;
+
+/// A Luau buffer type.
+///
+/// See the buffer [documentation] for more information.
+///
+/// [documentation]: https://luau.org/library#buffer-library
+#[cfg_attr(docsrs, doc(cfg(feature = "luau")))]
+#[derive(Clone, Debug, PartialEq)]
+pub struct Buffer(pub(crate) ValueRef);
+
+#[cfg_attr(not(feature = "luau"), allow(unused))]
+impl Buffer {
+    /// Copies the buffer data into a new `Vec<u8>`.
+    pub fn to_vec(&self) -> Vec<u8> {
+        let lua = self.0.lua.lock();
+        self.as_slice(&lua).to_vec()
+    }
+
+    /// Returns the length of the buffer.
+    pub fn len(&self) -> usize {
+        let lua = self.0.lua.lock();
+        self.as_slice(&lua).len()
+    }
+
+    /// Returns `true` if the buffer is empty.
+    pub fn is_empty(&self) -> bool {
+        self.len() == 0
+    }
+
+    /// Reads given number of bytes from the buffer at the given offset.
+    ///
+    /// Offset is 0-based.
+    #[track_caller]
+    pub fn read_bytes<const N: usize>(&self, offset: usize) -> [u8; N] {
+        let lua = self.0.lua.lock();
+        let data = self.as_slice(&lua);
+        let mut bytes = [0u8; N];
+        bytes.copy_from_slice(&data[offset..offset + N]);
+        bytes
+    }
+
+    /// Writes given bytes to the buffer at the given offset.
+    ///
+    /// Offset is 0-based.
+    #[track_caller]
+    pub fn write_bytes(&self, offset: usize, bytes: &[u8]) {
+        let lua = self.0.lua.lock();
+        let data = self.as_slice_mut(&lua);
+        data[offset..offset + bytes.len()].copy_from_slice(bytes);
+    }
+
+    /// Returns an adaptor implementing [`io::Read`], [`io::Write`] and [`io::Seek`] over the
+    /// buffer.
+    ///
+    /// Buffer operations are infallible, none of the read/write functions will return a Err.
+    pub fn cursor(self) -> impl io::Read + io::Write + io::Seek {
+        BufferCursor(self, 0)
+    }
+
+    pub(crate) fn as_slice(&self, lua: &RawLua) -> &[u8] {
+        unsafe {
+            let (buf, size) = self.as_raw_parts(lua);
+            std::slice::from_raw_parts(buf, size)
+        }
+    }
+
+    #[allow(clippy::mut_from_ref)]
+    fn as_slice_mut(&self, lua: &RawLua) -> &mut [u8] {
+        unsafe {
+            let (buf, size) = self.as_raw_parts(lua);
+            std::slice::from_raw_parts_mut(buf, size)
+        }
+    }
+
+    #[cfg(feature = "luau")]
+    unsafe fn as_raw_parts(&self, lua: &RawLua) -> (*mut u8, usize) {
+        let mut size = 0usize;
+        let buf = ffi::lua_tobuffer(lua.ref_thread(), self.0.index, &mut size);
+        mlua_assert!(!buf.is_null(), "invalid Luau buffer");
+        (buf as *mut u8, size)
+    }
+
+    #[cfg(not(feature = "luau"))]
+    unsafe fn as_raw_parts(&self, lua: &RawLua) -> (*mut u8, usize) {
+        unreachable!()
+    }
+}
+
+struct BufferCursor(Buffer, usize);
+
+impl io::Read for BufferCursor {
+    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
+        let lua = self.0 .0.lua.lock();
+        let data = self.0.as_slice(&lua);
+        if self.1 == data.len() {
+            return Ok(0);
+        }
+        let len = buf.len().min(data.len() - self.1);
+        buf[..len].copy_from_slice(&data[self.1..self.1 + len]);
+        self.1 += len;
+        Ok(len)
+    }
+}
+
+impl io::Write for BufferCursor {
+    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
+        let lua = self.0 .0.lua.lock();
+        let data = self.0.as_slice_mut(&lua);
+        if self.1 == data.len() {
+            return Ok(0);
+        }
+        let len = buf.len().min(data.len() - self.1);
+        data[self.1..self.1 + len].copy_from_slice(&buf[..len]);
+        self.1 += len;
+        Ok(len)
+    }
+
+    fn flush(&mut self) -> io::Result<()> {
+        Ok(())
+    }
+}
+
+impl io::Seek for BufferCursor {
+    fn seek(&mut self, pos: io::SeekFrom) -> io::Result<u64> {
+        let lua = self.0 .0.lua.lock();
+        let data = self.0.as_slice(&lua);
+        let new_offset = match pos {
+            io::SeekFrom::Start(offset) => offset as i64,
+            io::SeekFrom::End(offset) => data.len() as i64 + offset,
+            io::SeekFrom::Current(offset) => self.1 as i64 + offset,
+        };
+        if new_offset < 0 {
+            return Err(io::Error::new(
+                io::ErrorKind::InvalidInput,
+                "invalid seek to a negative position",
+            ));
+        }
+        if new_offset as usize > data.len() {
+            return Err(io::Error::new(
+                io::ErrorKind::InvalidInput,
+                "invalid seek to a position beyond the end of the buffer",
+            ));
+        }
+        self.1 = new_offset as usize;
+        Ok(self.1 as u64)
+    }
+}
+
+#[cfg(feature = "serde")]
+impl Serialize for Buffer {
+    fn serialize<S: Serializer>(&self, serializer: S) -> std::result::Result<S::Ok, S::Error> {
+        let lua = self.0.lua.lock();
+        serializer.serialize_bytes(self.as_slice(&lua))
+    }
+}
+
+#[cfg(feature = "luau")]
+impl crate::types::LuaType for Buffer {
+    const TYPE_ID: std::os::raw::c_int = ffi::LUA_TBUFFER;
+}

src/chunk.rs

@@ -0,0 +1,802 @@
+use std::borrow::Cow;
+use std::collections::HashMap;
+use std::ffi::CString;
+use std::io::Result as IoResult;
+use std::panic::Location;
+use std::path::{Path, PathBuf};
+use std::string::String as StdString;
+
+use crate::error::{Error, Result};
+use crate::function::Function;
+use crate::state::{Lua, WeakLua};
+use crate::table::Table;
+use crate::traits::{FromLuaMulti, IntoLua, IntoLuaMulti};
+use crate::value::Value;
+
+/// Trait for types [loadable by Lua] and convertible to a [`Chunk`]
+///
+/// [loadable by Lua]: https://www.lua.org/manual/5.4/manual.html#3.3.2
+pub trait AsChunk {
+    /// Returns optional chunk name
+    ///
+    /// See [`Chunk::set_name`] for possible name prefixes.
+    fn name(&self) -> Option<StdString> {
+        None
+    }
+
+    /// Returns optional chunk [environment]
+    ///
+    /// [environment]: https://www.lua.org/manual/5.4/manual.html#2.2
+    fn environment(&self, lua: &Lua) -> Result<Option<Table>> {
+        let _lua = lua; // suppress warning
+        Ok(None)
+    }
+
+    /// Returns optional chunk mode (text or binary)
+    fn mode(&self) -> Option<ChunkMode> {
+        None
+    }
+
+    /// Returns chunk data (can be text or binary)
+    fn source<'a>(&self) -> IoResult<Cow<'a, [u8]>>
+    where
+        Self: 'a;
+}
+
+impl AsChunk for &str {
+    fn source<'a>(&self) -> IoResult<Cow<'a, [u8]>>
+    where
+        Self: 'a,
+    {
+        Ok(Cow::Borrowed(self.as_bytes()))
+    }
+}
+
+impl AsChunk for StdString {
+    fn source<'a>(&self) -> IoResult<Cow<'a, [u8]>> {
+        Ok(Cow::Owned(self.clone().into_bytes()))
+    }
+}
+
+impl AsChunk for &StdString {
+    fn source<'a>(&self) -> IoResult<Cow<'a, [u8]>>
+    where
+        Self: 'a,
+    {
+        Ok(Cow::Borrowed(self.as_bytes()))
+    }
+}
+
+impl AsChunk for &[u8] {
+    fn source<'a>(&self) -> IoResult<Cow<'a, [u8]>>
+    where
+        Self: 'a,
+    {
+        Ok(Cow::Borrowed(self))
+    }
+}
+
+impl AsChunk for Vec<u8> {
+    fn source<'a>(&self) -> IoResult<Cow<'a, [u8]>> {
+        Ok(Cow::Owned(self.clone()))
+    }
+}
+
+impl AsChunk for &Vec<u8> {
+    fn source<'a>(&self) -> IoResult<Cow<'a, [u8]>>
+    where
+        Self: 'a,
+    {
+        Ok(Cow::Borrowed(self))
+    }
+}
+
+impl AsChunk for &Path {
+    fn name(&self) -> Option<StdString> {
+        Some(format!("@{}", self.display()))
+    }
+
+    fn source<'a>(&self) -> IoResult<Cow<'a, [u8]>> {
+        std::fs::read(self).map(Cow::Owned)
+    }
+}
+
+impl AsChunk for PathBuf {
+    fn name(&self) -> Option<StdString> {
+        Some(format!("@{}", self.display()))
+    }
+
+    fn source<'a>(&self) -> IoResult<Cow<'a, [u8]>> {
+        std::fs::read(self).map(Cow::Owned)
+    }
+}
+
+impl<C: AsChunk + ?Sized> AsChunk for Box<C> {
+    fn name(&self) -> Option<StdString> {
+        (**self).name()
+    }
+
+    fn environment(&self, lua: &Lua) -> Result<Option<Table>> {
+        (**self).environment(lua)
+    }
+
+    fn mode(&self) -> Option<ChunkMode> {
+        (**self).mode()
+    }
+
+    fn source<'a>(&self) -> IoResult<Cow<'a, [u8]>>
+    where
+        Self: 'a,
+    {
+        (**self).source()
+    }
+}
+
+/// Returned from [`Lua::load`] and is used to finalize loading and executing Lua main chunks.
+#[must_use = "`Chunk`s do nothing unless one of `exec`, `eval`, `call`, or `into_function` are called on them"]
+pub struct Chunk<'a> {
+    pub(crate) lua: WeakLua,
+    pub(crate) name: StdString,
+    pub(crate) env: Result<Option<Table>>,
+    pub(crate) mode: Option<ChunkMode>,
+    pub(crate) source: IoResult<Cow<'a, [u8]>>,
+    #[cfg(feature = "luau")]
+    pub(crate) compiler: Option<Compiler>,
+}
+
+/// Represents chunk mode (text or binary).
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub enum ChunkMode {
+    Text,
+    Binary,
+}
+
+/// Represents a constant value that can be used by Luau compiler.
+#[cfg(any(feature = "luau", doc))]
+#[cfg_attr(docsrs, doc(cfg(feature = "luau")))]
+#[derive(Clone, Debug)]
+pub enum CompileConstant {
+    Nil,
+    Boolean(bool),
+    Number(crate::Number),
+    Vector(crate::Vector),
+    String(StdString),
+}
+
+#[cfg(any(feature = "luau", doc))]
+impl From<bool> for CompileConstant {
+    fn from(b: bool) -> Self {
+        CompileConstant::Boolean(b)
+    }
+}
+
+#[cfg(any(feature = "luau", doc))]
+impl From<crate::Number> for CompileConstant {
+    fn from(n: crate::Number) -> Self {
+        CompileConstant::Number(n)
+    }
+}
+
+#[cfg(any(feature = "luau", doc))]
+impl From<crate::Vector> for CompileConstant {
+    fn from(v: crate::Vector) -> Self {
+        CompileConstant::Vector(v)
+    }
+}
+
+#[cfg(any(feature = "luau", doc))]
+impl From<&str> for CompileConstant {
+    fn from(s: &str) -> Self {
+        CompileConstant::String(s.to_owned())
+    }
+}
+
+#[cfg(any(feature = "luau", doc))]
+type LibraryMemberConstantMap = HashMap<(StdString, StdString), CompileConstant>;
+
+/// Luau compiler
+#[cfg(any(feature = "luau", doc))]
+#[cfg_attr(docsrs, doc(cfg(feature = "luau")))]
+#[derive(Clone, Debug)]
+pub struct Compiler {
+    optimization_level: u8,
+    debug_level: u8,
+    type_info_level: u8,
+    coverage_level: u8,
+    vector_lib: Option<StdString>,
+    vector_ctor: Option<StdString>,
+    vector_type: Option<StdString>,
+    mutable_globals: Vec<StdString>,
+    userdata_types: Vec<StdString>,
+    libraries_with_known_members: Vec<StdString>,
+    library_constants: Option<LibraryMemberConstantMap>,
+    disabled_builtins: Vec<StdString>,
+}
+
+#[cfg(any(feature = "luau", doc))]
+impl Default for Compiler {
+    fn default() -> Self {
+        const { Self::new() }
+    }
+}
+
+#[cfg(any(feature = "luau", doc))]
+impl Compiler {
+    /// Creates Luau compiler instance with default options
+    pub const fn new() -> Self {
+        // Defaults are taken from luacode.h
+        Compiler {
+            optimization_level: 1,
+            debug_level: 1,
+            type_info_level: 0,
+            coverage_level: 0,
+            vector_lib: None,
+            vector_ctor: None,
+            vector_type: None,
+            mutable_globals: Vec::new(),
+            userdata_types: Vec::new(),
+            libraries_with_known_members: Vec::new(),
+            library_constants: None,
+            disabled_builtins: Vec::new(),
+        }
+    }
+
+    /// Sets Luau compiler optimization level.
+    ///
+    /// Possible values:
+    /// * 0 - no optimization
+    /// * 1 - baseline optimization level that doesn't prevent debuggability (default)
+    /// * 2 - includes optimizations that harm debuggability such as inlining
+    #[must_use]
+    pub const fn set_optimization_level(mut self, level: u8) -> Self {
+        self.optimization_level = level;
+        self
+    }
+
+    /// Sets Luau compiler debug level.
+    ///
+    /// Possible values:
+    /// * 0 - no debugging support
+    /// * 1 - line info & function names only; sufficient for backtraces (default)
+    /// * 2 - full debug info with local & upvalue names; necessary for debugger
+    #[must_use]
+    pub const fn set_debug_level(mut self, level: u8) -> Self {
+        self.debug_level = level;
+        self
+    }
+
+    /// Sets Luau type information level used to guide native code generation decisions.
+    ///
+    /// Possible values:
+    /// * 0 - generate for native modules (default)
+    /// * 1 - generate for all modules
+    #[must_use]
+    pub const fn set_type_info_level(mut self, level: u8) -> Self {
+        self.type_info_level = level;
+        self
+    }
+
+    /// Sets Luau compiler code coverage level.
+    ///
+    /// Possible values:
+    /// * 0 - no code coverage support (default)
+    /// * 1 - statement coverage
+    /// * 2 - statement and expression coverage (verbose)
+    #[must_use]
+    pub const fn set_coverage_level(mut self, level: u8) -> Self {
+        self.coverage_level = level;
+        self
+    }
+
+    /// Sets alternative global builtin to construct vectors, in addition to default builtin
+    /// `vector.create`.
+    ///
+    /// To set the library and method name, use the `lib.ctor` format.
+    #[doc(hidden)]
+    #[must_use]
+    pub fn set_vector_ctor(mut self, ctor: impl Into<StdString>) -> Self {
+        let ctor = ctor.into();
+        let lib_ctor = ctor.split_once('.');
+        self.vector_lib = lib_ctor.as_ref().map(|&(lib, _)| lib.to_owned());
+        self.vector_ctor = (lib_ctor.as_ref())
+            .map(|&(_, ctor)| ctor.to_owned())
+            .or(Some(ctor));
+        self
+    }
+
+    /// Sets alternative vector type name for type tables, in addition to default type `vector`.
+    #[doc(hidden)]
+    #[must_use]
+    pub fn set_vector_type(mut self, r#type: impl Into<StdString>) -> Self {
+        self.vector_type = Some(r#type.into());
+        self
+    }
+
+    /// Adds a mutable global.
+    ///
+    /// It disables the import optimization for fields accessed through it.
+    #[must_use]
+    pub fn add_mutable_global(mut self, global: impl Into<StdString>) -> Self {
+        self.mutable_globals.push(global.into());
+        self
+    }
+
+    /// Sets a list of globals that are mutable.
+    ///
+    /// It disables the import optimization for fields accessed through these.
+    #[must_use]
+    pub fn set_mutable_globals<S: Into<StdString>>(mut self, globals: impl IntoIterator<Item = S>) -> Self {
+        self.mutable_globals = globals.into_iter().map(|s| s.into()).collect();
+        self
+    }
+
+    /// Adds a userdata type to the list that will be included in the type information.
+    #[must_use]
+    pub fn add_userdata_type(mut self, r#type: impl Into<StdString>) -> Self {
+        self.userdata_types.push(r#type.into());
+        self
+    }
+
+    /// Sets a list of userdata types that will be included in the type information.
+    #[must_use]
+    pub fn set_userdata_types<S: Into<StdString>>(mut self, types: impl IntoIterator<Item = S>) -> Self {
+        self.userdata_types = types.into_iter().map(|s| s.into()).collect();
+        self
+    }
+
+    /// Adds a constant for a known library member.
+    ///
+    /// The constants are used by the compiler to optimize the generated bytecode.
+    /// Optimization level must be at least 2 for this to have any effect.
+    ///
+    /// The `name` is a string in the format `lib.member`, where `lib` is the library name
+    /// and `member` is the member (constant) name.
+    #[must_use]
+    pub fn add_library_constant(
+        mut self,
+        name: impl AsRef<str>,
+        r#const: impl Into<CompileConstant>,
+    ) -> Self {
+        let Some((lib, member)) = name.as_ref().split_once('.') else {
+            return self;
+        };
+        let (lib, member) = (lib.to_owned(), member.to_owned());
+
+        if !self.libraries_with_known_members.contains(&lib) {
+            self.libraries_with_known_members.push(lib.clone());
+        }
+        self.library_constants
+            .get_or_insert_with(HashMap::new)
+            .insert((lib, member), r#const.into());
+        self
+    }
+
+    /// Adds a builtin that should be disabled.
+    #[must_use]
+    pub fn add_disabled_builtin(mut self, builtin: impl Into<StdString>) -> Self {
+        self.disabled_builtins.push(builtin.into());
+        self
+    }
+
+    /// Sets a list of builtins that should be disabled.
+    #[must_use]
+    pub fn set_disabled_builtins<S: Into<StdString>>(
+        mut self,
+        builtins: impl IntoIterator<Item = S>,
+    ) -> Self {
+        self.disabled_builtins = builtins.into_iter().map(|s| s.into()).collect();
+        self
+    }
+
+    /// Compiles the `source` into bytecode.
+    ///
+    /// Returns [`Error::SyntaxError`] if the source code is invalid.
+    pub fn compile(&self, source: impl AsRef<[u8]>) -> Result<Vec<u8>> {
+        use std::cell::RefCell;
+        use std::ffi::CStr;
+        use std::os::raw::{c_char, c_int};
+        use std::ptr;
+
+        let vector_lib = self.vector_lib.clone();
+        let vector_lib = vector_lib.and_then(|lib| CString::new(lib).ok());
+        let vector_lib = vector_lib.as_ref();
+        let vector_ctor = self.vector_ctor.clone();
+        let vector_ctor = vector_ctor.and_then(|ctor| CString::new(ctor).ok());
+        let vector_ctor = vector_ctor.as_ref();
+        let vector_type = self.vector_type.clone();
+        let vector_type = vector_type.and_then(|t| CString::new(t).ok());
+        let vector_type = vector_type.as_ref();
+
+        macro_rules! vec2cstring_ptr {
+            ($name:ident, $name_ptr:ident) => {
+                let $name = self
+                    .$name
+                    .iter()
+                    .map(|name| CString::new(name.clone()).ok())
+                    .collect::<Option<Vec<_>>>()
+                    .unwrap_or_default();
+                let mut $name = $name.iter().map(|s| s.as_ptr()).collect::<Vec<_>>();
+                let mut $name_ptr = ptr::null();
+                if !$name.is_empty() {
+                    $name.push(ptr::null());
+                    $name_ptr = $name.as_ptr();
+                }
+            };
+        }
+
+        vec2cstring_ptr!(mutable_globals, mutable_globals_ptr);
+        vec2cstring_ptr!(userdata_types, userdata_types_ptr);
+        vec2cstring_ptr!(libraries_with_known_members, libraries_with_known_members_ptr);
+        vec2cstring_ptr!(disabled_builtins, disabled_builtins_ptr);
+
+        thread_local! {
+            static LIBRARY_MEMBER_CONSTANT_MAP: RefCell<LibraryMemberConstantMap> = Default::default();
+        }
+
+        #[cfg(feature = "luau")]
+        unsafe extern "C-unwind" fn library_member_constant_callback(
+            library: *const c_char,
+            member: *const c_char,
+            constant: *mut ffi::lua_CompileConstant,
+        ) {
+            let library = CStr::from_ptr(library).to_string_lossy();
+            let member = CStr::from_ptr(member).to_string_lossy();
+            LIBRARY_MEMBER_CONSTANT_MAP.with_borrow(|map| {
+                if let Some(cons) = map.get(&(library.to_string(), member.to_string())) {
+                    match cons {
+                        CompileConstant::Nil => ffi::luau_set_compile_constant_nil(constant),
+                        CompileConstant::Boolean(b) => {
+                            ffi::luau_set_compile_constant_boolean(constant, *b as c_int)
+                        }
+                        CompileConstant::Number(n) => ffi::luau_set_compile_constant_number(constant, *n),
+                        CompileConstant::Vector(v) => {
+                            #[cfg(not(feature = "luau-vector4"))]
+                            ffi::luau_set_compile_constant_vector(constant, v.x(), v.y(), v.z(), 0.0);
+                            #[cfg(feature = "luau-vector4")]
+                            ffi::luau_set_compile_constant_vector(constant, v.x(), v.y(), v.z(), v.w());
+                        }
+                        CompileConstant::String(s) => ffi::luau_set_compile_constant_string(
+                            constant,
+                            s.as_ptr() as *const c_char,
+                            s.len(),
+                        ),
+                    }
+                }
+            })
+        }
+
+        let bytecode = unsafe {
+            let mut options = ffi::lua_CompileOptions::default();
+            options.optimizationLevel = self.optimization_level as c_int;
+            options.debugLevel = self.debug_level as c_int;
+            options.typeInfoLevel = self.type_info_level as c_int;
+            options.coverageLevel = self.coverage_level as c_int;
+            options.vectorLib = vector_lib.map_or(ptr::null(), |s| s.as_ptr());
+            options.vectorCtor = vector_ctor.map_or(ptr::null(), |s| s.as_ptr());
+            options.vectorType = vector_type.map_or(ptr::null(), |s| s.as_ptr());
+            options.mutableGlobals = mutable_globals_ptr;
+            options.userdataTypes = userdata_types_ptr;
+            options.librariesWithKnownMembers = libraries_with_known_members_ptr;
+            if let Some(map) = self.library_constants.as_ref() {
+                if !self.libraries_with_known_members.is_empty() {
+                    LIBRARY_MEMBER_CONSTANT_MAP.with_borrow_mut(|gmap| *gmap = map.clone());
+                    options.libraryMemberConstantCallback = Some(library_member_constant_callback);
+                }
+            }
+            options.disabledBuiltins = disabled_builtins_ptr;
+            ffi::luau_compile(source.as_ref(), options)
+        };
+
+        if bytecode.first() == Some(&0) {
+            // The rest of the bytecode is the error message starting with `:`
+            // See https://github.com/luau-lang/luau/blob/0.640/Compiler/src/Compiler.cpp#L4336
+            let message = StdString::from_utf8_lossy(&bytecode[2..]).into_owned();
+            return Err(Error::SyntaxError {
+                incomplete_input: message.ends_with("<eof>"),
+                message,
+            });
+        }
+
+        Ok(bytecode)
+    }
+}
+
+impl Chunk<'_> {
+    /// Returns the name of this chunk.
+    pub fn name(&self) -> &str {
+        &self.name
+    }
+
+    /// Sets the name of this chunk, which results in more informative error traces.
+    ///
+    /// Possible name prefixes:
+    /// - `@` - file path (when truncation is needed, the end of the file path is kept, as this is
+    ///   more useful for identifying the file)
+    /// - `=` - custom chunk name (when truncation is needed, the beginning of the name is kept)
+    pub fn set_name(mut self, name: impl Into<StdString>) -> Self {
+        self.name = name.into();
+        self
+    }
+
+    /// Returns the environment of this chunk.
+    pub fn environment(&self) -> Option<&Table> {
+        self.env.as_ref().ok()?.as_ref()
+    }
+
+    /// Sets the environment of the loaded chunk to the given value.
+    ///
+    /// In Lua >=5.2 main chunks always have exactly one upvalue, and this upvalue is used as the
+    /// `_ENV` variable inside the chunk. By default this value is set to the global environment.
+    ///
+    /// Calling this method changes the `_ENV` upvalue to the value provided, and variables inside
+    /// the chunk will refer to the given environment rather than the global one.
+    ///
+    /// All global variables (including the standard library!) are looked up in `_ENV`, so it may be
+    /// necessary to populate the environment in order for scripts using custom environments to be
+    /// useful.
+    pub fn set_environment(mut self, env: Table) -> Self {
+        self.env = Ok(Some(env));
+        self
+    }
+
+    /// Returns the mode (auto-detected by default) of this chunk.
+    pub fn mode(&self) -> ChunkMode {
+        self.detect_mode()
+    }
+
+    /// Sets whether the chunk is text or binary (autodetected by default).
+    ///
+    /// Be aware, Lua does not check the consistency of the code inside binary chunks.
+    /// Running maliciously crafted bytecode can crash the interpreter.
+    pub fn set_mode(mut self, mode: ChunkMode) -> Self {
+        self.mode = Some(mode);
+        self
+    }
+
+    /// Sets or overwrites a Luau compiler used for this chunk.
+    ///
+    /// See [`Compiler`] for details and possible options.
+    #[cfg(any(feature = "luau", doc))]
+    #[cfg_attr(docsrs, doc(cfg(feature = "luau")))]
+    pub fn set_compiler(mut self, compiler: Compiler) -> Self {
+        self.compiler = Some(compiler);
+        self
+    }
+
+    /// Execute this chunk of code.
+    ///
+    /// This is equivalent to calling the chunk function with no arguments and no return values.
+    pub fn exec(self) -> Result<()> {
+        self.call(())
+    }
+
+    /// Asynchronously execute this chunk of code.
+    ///
+    /// See [`exec`] for more details.
+    ///
+    /// [`exec`]: Chunk::exec
+    #[cfg(feature = "async")]
+    #[cfg_attr(docsrs, doc(cfg(feature = "async")))]
+    pub async fn exec_async(self) -> Result<()> {
+        self.call_async(()).await
+    }
+
+    /// Evaluate the chunk as either an expression or block.
+    ///
+    /// If the chunk can be parsed as an expression, this loads and executes the chunk and returns
+    /// the value that it evaluates to. Otherwise, the chunk is interpreted as a block as normal,
+    /// and this is equivalent to calling `exec`.
+    pub fn eval<R: FromLuaMulti>(self) -> Result<R> {
+        // Bytecode is always interpreted as a statement.
+        // For source code, first try interpreting the lua as an expression by adding
+        // "return", then as a statement. This is the same thing the
+        // actual lua repl does.
+        if self.detect_mode() == ChunkMode::Binary {
+            self.call(())
+        } else if let Ok(function) = self.to_expression() {
+            function.call(())
+        } else {
+            self.call(())
+        }
+    }
+
+    /// Asynchronously evaluate the chunk as either an expression or block.
+    ///
+    /// See [`eval`] for more details.
+    ///
+    /// [`eval`]: Chunk::eval
+    #[cfg(feature = "async")]
+    #[cfg_attr(docsrs, doc(cfg(feature = "async")))]
+    pub async fn eval_async<R>(self) -> Result<R>
+    where
+        R: FromLuaMulti,
+    {
+        if self.detect_mode() == ChunkMode::Binary {
+            self.call_async(()).await
+        } else if let Ok(function) = self.to_expression() {
+            function.call_async(()).await
+        } else {
+            self.call_async(()).await
+        }
+    }
+
+    /// Load the chunk function and call it with the given arguments.
+    ///
+    /// This is equivalent to `into_function` and calling the resulting function.
+    pub fn call<R: FromLuaMulti>(self, args: impl IntoLuaMulti) -> Result<R> {
+        self.into_function()?.call(args)
+    }
+
+    /// Load the chunk function and asynchronously call it with the given arguments.
+    ///
+    /// See [`call`] for more details.
+    ///
+    /// [`call`]: Chunk::call
+    #[cfg(feature = "async")]
+    #[cfg_attr(docsrs, doc(cfg(feature = "async")))]
+    pub async fn call_async<R>(self, args: impl IntoLuaMulti) -> Result<R>
+    where
+        R: FromLuaMulti,
+    {
+        self.into_function()?.call_async(args).await
+    }
+
+    /// Load this chunk into a regular [`Function`].
+    ///
+    /// This simply compiles the chunk without actually executing it.
+    #[cfg_attr(not(feature = "luau"), allow(unused_mut))]
+    pub fn into_function(mut self) -> Result<Function> {
+        #[cfg(feature = "luau")]
+        if self.compiler.is_some() {
+            // We don't need to compile source if no compiler set
+            self.compile();
+        }
+
+        let name = Self::convert_name(self.name)?;
+        self.lua
+            .lock()
+            .load_chunk(Some(&name), self.env?.as_ref(), self.mode, self.source?.as_ref())
+    }
+
+    /// Compiles the chunk and changes mode to binary.
+    ///
+    /// It does nothing if the chunk is already binary or invalid.
+    fn compile(&mut self) {
+        if let Ok(ref source) = self.source {
+            if self.detect_mode() == ChunkMode::Text {
+                #[cfg(feature = "luau")]
+                if let Ok(data) = self.compiler.get_or_insert_with(Default::default).compile(source) {
+                    self.source = Ok(Cow::Owned(data));
+                    self.mode = Some(ChunkMode::Binary);
+                }
+                #[cfg(not(feature = "luau"))]
+                if let Ok(func) = self.lua.lock().load_chunk(None, None, None, source.as_ref()) {
+                    let data = func.dump(false);
+                    self.source = Ok(Cow::Owned(data));
+                    self.mode = Some(ChunkMode::Binary);
+                }
+            }
+        }
+    }
+
+    /// Fetches compiled bytecode of this chunk from the cache.
+    ///
+    /// If not found, compiles the source code and stores it on the cache.
+    pub(crate) fn try_cache(mut self) -> Self {
+        struct ChunksCache(HashMap<Vec<u8>, Vec<u8>>);
+
+        // Try to fetch compiled chunk from cache
+        let mut text_source = None;
+        if let Ok(ref source) = self.source {
+            if self.detect_mode() == ChunkMode::Text {
+                let lua = self.lua.lock();
+                if let Some(cache) = lua.priv_app_data_ref::<ChunksCache>() {
+                    if let Some(data) = cache.0.get(source.as_ref()) {
+                        self.source = Ok(Cow::Owned(data.clone()));
+                        self.mode = Some(ChunkMode::Binary);
+                        return self;
+                    }
+                }
+                text_source = Some(source.as_ref().to_vec());
+            }
+        }
+
+        // Compile and cache the chunk
+        if let Some(text_source) = text_source {
+            self.compile();
+            if let Ok(ref binary_source) = self.source {
+                if self.detect_mode() == ChunkMode::Binary {
+                    let lua = self.lua.lock();
+                    if let Some(mut cache) = lua.priv_app_data_mut::<ChunksCache>() {
+                        cache.0.insert(text_source, binary_source.to_vec());
+                    } else {
+                        let mut cache = ChunksCache(HashMap::new());
+                        cache.0.insert(text_source, binary_source.to_vec());
+                        lua.set_priv_app_data(cache);
+                    };
+                }
+            }
+        }
+
+        self
+    }
+
+    fn to_expression(&self) -> Result<Function> {
+        // We assume that mode is Text
+        let source = self.source.as_ref();
+        let source = source.map_err(Error::runtime)?;
+        let source = Self::expression_source(source);
+        // We don't need to compile source if no compiler options set
+        #[cfg(feature = "luau")]
+        let source = self
+            .compiler
+            .as_ref()
+            .map(|c| c.compile(&source))
+            .transpose()?
+            .unwrap_or(source);
+
+        let name = Self::convert_name(self.name.clone())?;
+        let env = match &self.env {
+            Ok(Some(env)) => Some(env),
+            Ok(None) => None,
+            Err(err) => return Err(err.clone()),
+        };
+        self.lua.lock().load_chunk(Some(&name), env, None, &source)
+    }
+
+    fn detect_mode(&self) -> ChunkMode {
+        if let Some(mode) = self.mode {
+            return mode;
+        }
+        if let Ok(source) = &self.source {
+            #[cfg(not(feature = "luau"))]
+            if source.starts_with(ffi::LUA_SIGNATURE) {
+                return ChunkMode::Binary;
+            }
+            #[cfg(feature = "luau")]
+            if *source.first().unwrap_or(&u8::MAX) < b'\n' {
+                return ChunkMode::Binary;
+            }
+        }
+        ChunkMode::Text
+    }
+
+    fn convert_name(name: StdString) -> Result<CString> {
+        CString::new(name).map_err(|err| Error::runtime(format!("invalid name: {err}")))
+    }
+
+    fn expression_source(source: &[u8]) -> Vec<u8> {
+        let mut buf = Vec::with_capacity(b"return ".len() + source.len());
+        buf.extend(b"return ");
+        buf.extend(source);
+        buf
+    }
+}
+
+struct WrappedChunk<T: AsChunk> {
+    chunk: T,
+    caller: &'static Location<'static>,
+}
+
+impl Chunk<'_> {
+    /// Wraps a chunk of Lua code, returning an opaque type that implements [`IntoLua`] trait.
+    ///
+    /// The resulted `IntoLua` implementation will convert the chunk into a Lua function without
+    /// executing it.
+    #[doc(hidden)]
+    #[track_caller]
+    pub fn wrap(chunk: impl AsChunk) -> impl IntoLua {
+        WrappedChunk {
+            chunk,
+            caller: Location::caller(),
+        }
+    }
+}
+
+impl<T: AsChunk> IntoLua for WrappedChunk<T> {
+    fn into_lua(self, lua: &Lua) -> Result<Value> {
+        lua.load_with_location(self.chunk, self.caller)
+            .into_function()
+            .map(Value::Function)
+    }
+}

src/debug.rs

@@ -0,0 +1,387 @@
+use std::borrow::Cow;
+use std::os::raw::c_int;
+
+use ffi::{lua_Debug, lua_State};
+
+use crate::function::Function;
+use crate::state::RawLua;
+use crate::util::{assert_stack, linenumber_to_usize, ptr_to_lossy_str, ptr_to_str, StackGuard};
+
+/// Contains information about currently executing Lua code.
+///
+/// You may call the methods on this structure to retrieve information about the Lua code executing
+/// at the specific level. Further information can be found in the Lua [documentation].
+///
+/// [documentation]: https://www.lua.org/manual/5.4/manual.html#lua_Debug
+pub struct Debug<'a> {
+    state: *mut lua_State,
+    lua: &'a RawLua,
+    #[cfg_attr(not(feature = "luau"), allow(unused))]
+    level: c_int,
+    ar: *mut lua_Debug,
+}
+
+impl<'a> Debug<'a> {
+    pub(crate) fn new(lua: &'a RawLua, level: c_int, ar: *mut lua_Debug) -> Self {
+        Debug {
+            state: lua.state(),
+            lua,
+            ar,
+            level,
+        }
+    }
+
+    /// Returns the specific event that triggered the hook.
+    ///
+    /// For [Lua 5.1] [`DebugEvent::TailCall`] is used for return events to indicate a return
+    /// from a function that did a tail call.
+    ///
+    /// [Lua 5.1]: https://www.lua.org/manual/5.1/manual.html#pdf-LUA_HOOKTAILRET
+    #[cfg(not(feature = "luau"))]
+    #[cfg_attr(docsrs, doc(cfg(not(feature = "luau"))))]
+    pub fn event(&self) -> DebugEvent {
+        unsafe {
+            match (*self.ar).event {
+                ffi::LUA_HOOKCALL => DebugEvent::Call,
+                ffi::LUA_HOOKRET => DebugEvent::Ret,
+                ffi::LUA_HOOKTAILCALL => DebugEvent::TailCall,
+                ffi::LUA_HOOKLINE => DebugEvent::Line,
+                ffi::LUA_HOOKCOUNT => DebugEvent::Count,
+                event => DebugEvent::Unknown(event),
+            }
+        }
+    }
+
+    /// Returns the function that is running at the given level.
+    ///
+    /// Corresponds to the `f` "what" mask.
+    pub fn function(&self) -> Function {
+        unsafe {
+            let _sg = StackGuard::new(self.state);
+            assert_stack(self.state, 1);
+
+            #[cfg(not(feature = "luau"))]
+            mlua_assert!(
+                ffi::lua_getinfo(self.state, cstr!("f"), self.ar) != 0,
+                "lua_getinfo failed with `f`"
+            );
+            #[cfg(feature = "luau")]
+            mlua_assert!(
+                ffi::lua_getinfo(self.state, self.level, cstr!("f"), self.ar) != 0,
+                "lua_getinfo failed with `f`"
+            );
+
+            ffi::lua_xmove(self.state, self.lua.ref_thread(), 1);
+            Function(self.lua.pop_ref_thread())
+        }
+    }
+
+    /// Corresponds to the `n` "what" mask.
+    pub fn names(&self) -> DebugNames<'_> {
+        unsafe {
+            #[cfg(not(feature = "luau"))]
+            mlua_assert!(
+                ffi::lua_getinfo(self.state, cstr!("n"), self.ar) != 0,
+                "lua_getinfo failed with `n`"
+            );
+            #[cfg(feature = "luau")]
+            mlua_assert!(
+                ffi::lua_getinfo(self.state, self.level, cstr!("n"), self.ar) != 0,
+                "lua_getinfo failed with `n`"
+            );
+
+            DebugNames {
+                name: ptr_to_lossy_str((*self.ar).name),
+                #[cfg(not(feature = "luau"))]
+                name_what: match ptr_to_str((*self.ar).namewhat) {
+                    Some("") => None,
+                    val => val,
+                },
+                #[cfg(feature = "luau")]
+                name_what: None,
+            }
+        }
+    }
+
+    /// Corresponds to the `S` "what" mask.
+    pub fn source(&self) -> DebugSource<'_> {
+        unsafe {
+            #[cfg(not(feature = "luau"))]
+            mlua_assert!(
+                ffi::lua_getinfo(self.state, cstr!("S"), self.ar) != 0,
+                "lua_getinfo failed with `S`"
+            );
+            #[cfg(feature = "luau")]
+            mlua_assert!(
+                ffi::lua_getinfo(self.state, self.level, cstr!("s"), self.ar) != 0,
+                "lua_getinfo failed with `s`"
+            );
+
+            DebugSource {
+                source: ptr_to_lossy_str((*self.ar).source),
+                #[cfg(not(feature = "luau"))]
+                short_src: ptr_to_lossy_str((*self.ar).short_src.as_ptr()),
+                #[cfg(feature = "luau")]
+                short_src: ptr_to_lossy_str((*self.ar).short_src),
+                line_defined: linenumber_to_usize((*self.ar).linedefined),
+                #[cfg(not(feature = "luau"))]
+                last_line_defined: linenumber_to_usize((*self.ar).lastlinedefined),
+                #[cfg(feature = "luau")]
+                last_line_defined: None,
+                what: ptr_to_str((*self.ar).what).unwrap_or("main"),
+            }
+        }
+    }
+
+    #[doc(hidden)]
+    #[deprecated(note = "Use `current_line` instead")]
+    pub fn curr_line(&self) -> i32 {
+        self.current_line().map(|n| n as i32).unwrap_or(-1)
+    }
+
+    /// Corresponds to the `l` "what" mask. Returns the current line.
+    pub fn current_line(&self) -> Option<usize> {
+        unsafe {
+            #[cfg(not(feature = "luau"))]
+            mlua_assert!(
+                ffi::lua_getinfo(self.state, cstr!("l"), self.ar) != 0,
+                "lua_getinfo failed with `l`"
+            );
+            #[cfg(feature = "luau")]
+            mlua_assert!(
+                ffi::lua_getinfo(self.state, self.level, cstr!("l"), self.ar) != 0,
+                "lua_getinfo failed with `l`"
+            );
+
+            linenumber_to_usize((*self.ar).currentline)
+        }
+    }
+
+    /// Corresponds to the `t` "what" mask. Returns true if the hook is in a function tail call,
+    /// false otherwise.
+    #[cfg(any(feature = "lua54", feature = "lua53", feature = "lua52"))]
+    #[cfg_attr(
+        docsrs,
+        doc(cfg(any(feature = "lua54", feature = "lua53", feature = "lua52")))
+    )]
+    pub fn is_tail_call(&self) -> bool {
+        unsafe {
+            mlua_assert!(
+                ffi::lua_getinfo(self.state, cstr!("t"), self.ar) != 0,
+                "lua_getinfo failed with `t`"
+            );
+            (*self.ar).istailcall != 0
+        }
+    }
+
+    /// Corresponds to the `u` "what" mask.
+    pub fn stack(&self) -> DebugStack {
+        unsafe {
+            #[cfg(not(feature = "luau"))]
+            mlua_assert!(
+                ffi::lua_getinfo(self.state, cstr!("u"), self.ar) != 0,
+                "lua_getinfo failed with `u`"
+            );
+            #[cfg(feature = "luau")]
+            mlua_assert!(
+                ffi::lua_getinfo(self.state, self.level, cstr!("au"), self.ar) != 0,
+                "lua_getinfo failed with `au`"
+            );
+
+            #[cfg(not(feature = "luau"))]
+            let stack = DebugStack {
+                num_ups: (*self.ar).nups as _,
+                #[cfg(any(feature = "lua54", feature = "lua53", feature = "lua52"))]
+                num_params: (*self.ar).nparams as _,
+                #[cfg(any(feature = "lua54", feature = "lua53", feature = "lua52"))]
+                is_vararg: (*self.ar).isvararg != 0,
+            };
+            #[cfg(feature = "luau")]
+            let stack = DebugStack {
+                num_ups: (*self.ar).nupvals,
+                num_params: (*self.ar).nparams,
+                is_vararg: (*self.ar).isvararg != 0,
+            };
+            stack
+        }
+    }
+}
+
+/// Represents a specific event that triggered the hook.
+#[derive(Clone, Copy, Debug, PartialEq, Eq)]
+pub enum DebugEvent {
+    Call,
+    Ret,
+    TailCall,
+    Line,
+    Count,
+    Unknown(c_int),
+}
+
+#[derive(Clone, Debug)]
+pub struct DebugNames<'a> {
+    /// A (reasonable) name of the function (`None` if the name cannot be found).
+    pub name: Option<Cow<'a, str>>,
+    /// Explains the `name` field (can be `global`/`local`/`method`/`field`/`upvalue`/etc).
+    ///
+    /// Always `None` for Luau.
+    pub name_what: Option<&'static str>,
+}
+
+#[derive(Clone, Debug)]
+pub struct DebugSource<'a> {
+    /// Source of the chunk that created the function.
+    pub source: Option<Cow<'a, str>>,
+    /// A "printable" version of `source`, to be used in error messages.
+    pub short_src: Option<Cow<'a, str>>,
+    /// The line number where the definition of the function starts.
+    pub line_defined: Option<usize>,
+    /// The line number where the definition of the function ends (not set by Luau).
+    pub last_line_defined: Option<usize>,
+    /// A string `Lua` if the function is a Lua function, `C` if it is a C function, `main` if it is
+    /// the main part of a chunk.
+    pub what: &'static str,
+}
+
+#[derive(Copy, Clone, Debug)]
+pub struct DebugStack {
+    /// Number of upvalues.
+    pub num_ups: u8,
+    /// Number of parameters.
+    #[cfg(any(feature = "lua54", feature = "lua53", feature = "lua52", feature = "luau"))]
+    #[cfg_attr(
+        docsrs,
+        doc(cfg(any(feature = "lua54", feature = "lua53", feature = "lua52", feature = "luau")))
+    )]
+    pub num_params: u8,
+    /// Whether the function is a vararg function.
+    #[cfg(any(feature = "lua54", feature = "lua53", feature = "lua52", feature = "luau"))]
+    #[cfg_attr(
+        docsrs,
+        doc(cfg(any(feature = "lua54", feature = "lua53", feature = "lua52", feature = "luau")))
+    )]
+    pub is_vararg: bool,
+}
+
+/// Determines when a hook function will be called by Lua.
+#[cfg(not(feature = "luau"))]
+#[cfg_attr(docsrs, doc(cfg(not(feature = "luau"))))]
+#[derive(Clone, Copy, Debug, Default)]
+pub struct HookTriggers {
+    /// Before a function call.
+    pub on_calls: bool,
+    /// When Lua returns from a function.
+    pub on_returns: bool,
+    /// Before executing a new line, or returning from a function call.
+    pub every_line: bool,
+    /// After a certain number of VM instructions have been executed. When set to `Some(count)`,
+    /// `count` is the number of VM instructions to execute before calling the hook.
+    ///
+    /// # Performance
+    ///
+    /// Setting this option to a low value can incur a very high overhead.
+    pub every_nth_instruction: Option<u32>,
+}
+
+#[cfg(not(feature = "luau"))]
+impl HookTriggers {
+    /// An instance of `HookTriggers` with `on_calls` trigger set.
+    pub const ON_CALLS: Self = HookTriggers::new().on_calls();
+
+    /// An instance of `HookTriggers` with `on_returns` trigger set.
+    pub const ON_RETURNS: Self = HookTriggers::new().on_returns();
+
+    /// An instance of `HookTriggers` with `every_line` trigger set.
+    pub const EVERY_LINE: Self = HookTriggers::new().every_line();
+
+    /// Returns a new instance of `HookTriggers` with all triggers disabled.
+    pub const fn new() -> Self {
+        HookTriggers {
+            on_calls: false,
+            on_returns: false,
+            every_line: false,
+            every_nth_instruction: None,
+        }
+    }
+
+    /// Returns an instance of `HookTriggers` with [`on_calls`] trigger set.
+    ///
+    /// [`on_calls`]: #structfield.on_calls
+    pub const fn on_calls(mut self) -> Self {
+        self.on_calls = true;
+        self
+    }
+
+    /// Returns an instance of `HookTriggers` with [`on_returns`] trigger set.
+    ///
+    /// [`on_returns`]: #structfield.on_returns
+    pub const fn on_returns(mut self) -> Self {
+        self.on_returns = true;
+        self
+    }
+
+    /// Returns an instance of `HookTriggers` with [`every_line`] trigger set.
+    ///
+    /// [`every_line`]: #structfield.every_line
+    pub const fn every_line(mut self) -> Self {
+        self.every_line = true;
+        self
+    }
+
+    /// Returns an instance of `HookTriggers` with [`every_nth_instruction`] trigger set.
+    ///
+    /// [`every_nth_instruction`]: #structfield.every_nth_instruction
+    pub const fn every_nth_instruction(mut self, n: u32) -> Self {
+        self.every_nth_instruction = Some(n);
+        self
+    }
+
+    // Compute the mask to pass to `lua_sethook`.
+    pub(crate) const fn mask(&self) -> c_int {
+        let mut mask: c_int = 0;
+        if self.on_calls {
+            mask |= ffi::LUA_MASKCALL
+        }
+        if self.on_returns {
+            mask |= ffi::LUA_MASKRET
+        }
+        if self.every_line {
+            mask |= ffi::LUA_MASKLINE
+        }
+        if self.every_nth_instruction.is_some() {
+            mask |= ffi::LUA_MASKCOUNT
+        }
+        mask
+    }
+
+    // Returns the `count` parameter to pass to `lua_sethook`, if applicable. Otherwise, zero is
+    // returned.
+    pub(crate) const fn count(&self) -> c_int {
+        match self.every_nth_instruction {
+            Some(n) => n as c_int,
+            None => 0,
+        }
+    }
+}
+
+#[cfg(not(feature = "luau"))]
+impl std::ops::BitOr for HookTriggers {
+    type Output = Self;
+
+    fn bitor(mut self, rhs: Self) -> Self::Output {
+        self.on_calls |= rhs.on_calls;
+        self.on_returns |= rhs.on_returns;
+        self.every_line |= rhs.every_line;
+        if self.every_nth_instruction.is_none() && rhs.every_nth_instruction.is_some() {
+            self.every_nth_instruction = rhs.every_nth_instruction;
+        }
+        self
+    }
+}
+
+#[cfg(not(feature = "luau"))]
+impl std::ops::BitOrAssign for HookTriggers {
+    fn bitor_assign(&mut self, rhs: Self) {
+        *self = *self | rhs;
+    }
+}

src/error.rs

@@ -1,11 +1,23 @@
 use std::error::Error as StdError;
 use std::fmt;
+use std::io::Error as IoError;
+use std::net::AddrParseError;
 use std::result::Result as StdResult;
+use std::str::Utf8Error;
 use std::string::String as StdString;
 use std::sync::Arc;
 
+use crate::private::Sealed;
+
+#[cfg(feature = "error-send")]
+type DynStdError = dyn StdError + Send + Sync;
+
+#[cfg(not(feature = "error-send"))]
+type DynStdError = dyn StdError;
+
 /// Error type returned by `mlua` methods.
 #[derive(Debug, Clone)]
+#[non_exhaustive]
 pub enum Error {
     /// Syntax error while parsing Lua source code.
     SyntaxError {
@@ -31,8 +43,16 @@ pub enum Error {
     /// Lua garbage collector error, aka `LUA_ERRGCMM`.
     ///
     /// The Lua VM returns this error when there is an error running a `__gc` metamethod.
-    #[cfg(any(feature = "lua53", feature = "lua52"))]
+    #[cfg(any(feature = "lua53", feature = "lua52", doc))]
+    #[cfg_attr(docsrs, doc(cfg(any(feature = "lua53", feature = "lua52"))))]
     GarbageCollectorError(StdString),
+    /// Potentially unsafe action in safe mode.
+    SafetyError(StdString),
+    /// Memory control is not available.
+    ///
+    /// This error can only happen when Lua state was not created by us and does not have the
+    /// custom allocator attached.
+    MemoryControlNotAvailable,
     /// A mutable callback has triggered Lua code that has called the same mutable callback again.
     ///
     /// This is an error because a mutable callback can only be borrowed mutably once.
@@ -47,15 +67,31 @@ pub enum Error {
     ///
     /// Due to the way `mlua` works, it should not be directly possible to run out of stack space
     /// during normal use. The only way that this error can be triggered is if a `Function` is
-    /// called with a huge number of arguments, or a rust callback returns a huge number of return
+    /// called with a huge number of arguments, or a Rust callback returns a huge number of return
     /// values.
     StackError,
-    /// Too many arguments to `Function::bind`
+    /// Too many arguments to [`Function::bind`].
+    ///
+    /// [`Function::bind`]: crate::Function::bind
     BindError,
+    /// Bad argument received from Lua (usually when calling a function).
+    ///
+    /// This error can help to identify the argument that caused the error
+    /// (which is stored in the corresponding field).
+    BadArgument {
+        /// Function that was called.
+        to: Option<StdString>,
+        /// Argument position (usually starts from 1).
+        pos: usize,
+        /// Argument name.
+        name: Option<StdString>,
+        /// Underlying error returned when converting argument to a Lua value.
+        cause: Arc<Error>,
+    },
     /// A Rust value could not be converted to a Lua value.
     ToLuaConversionError {
         /// Name of the Rust type that could not be converted.
-        from: &'static str,
+        from: String,
         /// Name of the Lua type that could not be created.
         to: &'static str,
         /// A message indicating why the conversion failed in more detail.
@@ -66,49 +102,73 @@ pub enum Error {
         /// Name of the Lua type that could not be converted.
         from: &'static str,
         /// Name of the Rust type that could not be created.
-        to: &'static str,
+        to: String,
         /// A string containing more detailed error information.
         message: Option<StdString>,
     },
-    /// [`Thread::resume`] was called on an inactive coroutine.
+    /// [`Thread::resume`] was called on an unresumable coroutine.
     ///
-    /// A coroutine is inactive if its main function has returned or if an error has occured inside
-    /// the coroutine.
+    /// A coroutine is unresumable if its main function has returned or if an error has occurred
+    /// inside the coroutine. Already running coroutines are also marked as unresumable.
     ///
     /// [`Thread::status`] can be used to check if the coroutine can be resumed without causing this
     /// error.
     ///
-    /// [`Thread::resume`]: struct.Thread.html#method.resume
-    /// [`Thread::status`]: struct.Thread.html#method.status
-    CoroutineInactive,
+    /// [`Thread::resume`]: crate::Thread::resume
+    /// [`Thread::status`]: crate::Thread::status
+    CoroutineUnresumable,
     /// An [`AnyUserData`] is not the expected type in a borrow.
     ///
     /// This error can only happen when manually using [`AnyUserData`], or when implementing
     /// metamethods for binary operators. Refer to the documentation of [`UserDataMethods`] for
     /// details.
     ///
-    /// [`AnyUserData`]: struct.AnyUserData.html
-    /// [`UserDataMethods`]: trait.UserDataMethods.html
+    /// [`AnyUserData`]: crate::AnyUserData
+    /// [`UserDataMethods`]: crate::UserDataMethods
     UserDataTypeMismatch,
-    /// An [`AnyUserData`] immutable borrow failed because it is already borrowed mutably.
+    /// An [`AnyUserData`] borrow failed because it has been destructed.
+    ///
+    /// This error can happen either due to to being destructed in a previous __gc, or due to being
+    /// destructed from exiting a `Lua::scope` call.
+    ///
+    /// [`AnyUserData`]: crate::AnyUserData
+    UserDataDestructed,
+    /// An [`AnyUserData`] immutable borrow failed.
     ///
     /// This error can occur when a method on a [`UserData`] type calls back into Lua, which then
     /// tries to call a method on the same [`UserData`] type. Consider restructuring your API to
     /// prevent these errors.
     ///
-    /// [`AnyUserData`]: struct.AnyUserData.html
-    /// [`UserData`]: trait.UserData.html
+    /// [`AnyUserData`]: crate::AnyUserData
+    /// [`UserData`]: crate::UserData
     UserDataBorrowError,
-    /// An [`AnyUserData`] mutable borrow failed because it is already borrowed.
+    /// An [`AnyUserData`] mutable borrow failed.
     ///
     /// This error can occur when a method on a [`UserData`] type calls back into Lua, which then
     /// tries to call a method on the same [`UserData`] type. Consider restructuring your API to
     /// prevent these errors.
     ///
-    /// [`AnyUserData`]: struct.AnyUserData.html
-    /// [`UserData`]: trait.UserData.html
+    /// [`AnyUserData`]: crate::AnyUserData
+    /// [`UserData`]: crate::UserData
     UserDataBorrowMutError,
-    /// A `RegistryKey` produced from a different Lua state was used.
+    /// A [`MetaMethod`] operation is restricted (typically for `__gc` or `__metatable`).
+    ///
+    /// [`MetaMethod`]: crate::MetaMethod
+    MetaMethodRestricted(StdString),
+    /// A [`MetaMethod`] (eg. `__index` or `__newindex`) has invalid type.
+    ///
+    /// [`MetaMethod`]: crate::MetaMethod
+    MetaMethodTypeError {
+        /// Name of the metamethod.
+        method: StdString,
+        /// Passed value type.
+        type_name: &'static str,
+        /// A string containing more detailed error information.
+        message: Option<StdString>,
+    },
+    /// A [`RegistryKey`] produced from a different Lua state was used.
+    ///
+    /// [`RegistryKey`]: crate::RegistryKey
     MismatchedRegistryKey,
     /// A Rust callback returned `Err`, raising the contained `Error` as a Lua error.
     CallbackError {
@@ -117,6 +177,19 @@ pub enum Error {
         /// Original error returned by the Rust code.
         cause: Arc<Error>,
     },
+    /// A Rust panic that was previously resumed, returned again.
+    ///
+    /// This error can occur only when a Rust panic resumed previously was recovered
+    /// and returned again.
+    PreviouslyResumedPanic,
+    /// Serialization error.
+    #[cfg(feature = "serde")]
+    #[cfg_attr(docsrs, doc(cfg(feature = "serde")))]
+    SerializeError(StdString),
+    /// Deserialization error.
+    #[cfg(feature = "serde")]
+    #[cfg_attr(docsrs, doc(cfg(feature = "serde")))]
+    DeserializeError(StdString),
     /// A custom error.
     ///
     /// This can be used for returning user-defined errors from callbacks.
@@ -124,23 +197,37 @@ pub enum Error {
     /// Returning `Err(ExternalError(...))` from a Rust callback will raise the error as a Lua
     /// error. The Rust code that originally invoked the Lua code then receives a `CallbackError`,
     /// from which the original error (and a stack traceback) can be recovered.
-    ExternalError(Arc<dyn StdError + Send + Sync>),
+    ExternalError(Arc<DynStdError>),
+    /// An error with additional context.
+    WithContext {
+        /// A string containing additional context.
+        context: StdString,
+        /// Underlying error.
+        cause: Arc<Error>,
+    },
 }
 
 /// A specialized `Result` type used by `mlua`'s API.
 pub type Result<T> = StdResult<T, Error>;
 
+#[cfg(not(tarpaulin_include))]
 impl fmt::Display for Error {
     fn fmt(&self, fmt: &mut fmt::Formatter) -> fmt::Result {
-        match *self {
-            Error::SyntaxError { ref message, .. } => write!(fmt, "syntax error: {}", message),
-            Error::RuntimeError(ref msg) => write!(fmt, "runtime error: {}", msg),
-            Error::MemoryError(ref msg) => {
-                write!(fmt, "memory error: {}", msg)
+        match self {
+            Error::SyntaxError { message, .. } => write!(fmt, "syntax error: {message}"),
+            Error::RuntimeError(msg) => write!(fmt, "runtime error: {msg}"),
+            Error::MemoryError(msg) => {
+                write!(fmt, "memory error: {msg}")
             }
             #[cfg(any(feature = "lua53", feature = "lua52"))]
-            Error::GarbageCollectorError(ref msg) => {
-                write!(fmt, "garbage collector error: {}", msg)
+            Error::GarbageCollectorError(msg) => {
+                write!(fmt, "garbage collector error: {msg}")
+            }
+            Error::SafetyError(msg) => {
+                write!(fmt, "safety error: {msg}")
+            },
+            Error::MemoryControlNotAvailable => {
+                write!(fmt, "memory control is not available")
             }
             Error::RecursiveMutCallback => write!(fmt, "mutable callback called recursively"),
             Error::CallbackDestructed => write!(
@@ -155,81 +242,329 @@ impl fmt::Display for Error {
                 fmt,
                 "too many arguments to Function::bind"
             ),
-            Error::ToLuaConversionError {
-                from,
-                to,
-                ref message,
-            } => {
-                write!(fmt, "error converting {} to Lua {}", from, to)?;
-                match *message {
+            Error::BadArgument { to, pos, name, cause } => {
+                if let Some(name) = name {
+                    write!(fmt, "bad argument `{name}`")?;
+                } else {
+                    write!(fmt, "bad argument #{pos}")?;
+                }
+                if let Some(to) = to {
+                    write!(fmt, " to `{to}`")?;
+                }
+                write!(fmt, ": {cause}")
+            },
+            Error::ToLuaConversionError { from, to, message } => {
+                write!(fmt, "error converting {from} to Lua {to}")?;
+                match message {
                     None => Ok(()),
-                    Some(ref message) => write!(fmt, " ({})", message),
+                    Some(message) => write!(fmt, " ({message})"),
                 }
             }
-            Error::FromLuaConversionError {
-                from,
-                to,
-                ref message,
-            } => {
-                write!(fmt, "error converting Lua {} to {}", from, to)?;
-                match *message {
+            Error::FromLuaConversionError { from, to, message } => {
+                write!(fmt, "error converting Lua {from} to {to}")?;
+                match message {
                     None => Ok(()),
-                    Some(ref message) => write!(fmt, " ({})", message),
+                    Some(message) => write!(fmt, " ({message})"),
                 }
             }
-            Error::CoroutineInactive => write!(fmt, "cannot resume inactive coroutine"),
+            Error::CoroutineUnresumable => write!(fmt, "coroutine is non-resumable"),
             Error::UserDataTypeMismatch => write!(fmt, "userdata is not expected type"),
-            Error::UserDataBorrowError => write!(fmt, "userdata already mutably borrowed"),
-            Error::UserDataBorrowMutError => write!(fmt, "userdata already borrowed"),
+            Error::UserDataDestructed => write!(fmt, "userdata has been destructed"),
+            Error::UserDataBorrowError => write!(fmt, "error borrowing userdata"),
+            Error::UserDataBorrowMutError => write!(fmt, "error mutably borrowing userdata"),
+            Error::MetaMethodRestricted(method) => write!(fmt, "metamethod {method} is restricted"),
+            Error::MetaMethodTypeError { method, type_name, message } => {
+                write!(fmt, "metamethod {method} has unsupported type {type_name}")?;
+                match message {
+                    None => Ok(()),
+                    Some(message) => write!(fmt, " ({message})"),
+                }
+            }
             Error::MismatchedRegistryKey => {
                 write!(fmt, "RegistryKey used from different Lua state")
             }
-            Error::CallbackError { ref traceback, ref cause } => {
-                write!(fmt, "callback error: {}: {}", cause, traceback)
+            Error::CallbackError { cause, traceback } => {
+                // Trace errors down to the root
+                let (mut cause, mut full_traceback) = (cause, None);
+                while let Error::CallbackError { cause: cause2, traceback: traceback2 } = &**cause {
+                    cause = cause2;
+                    full_traceback = Some(traceback2);
+                }
+                writeln!(fmt, "{cause}")?;
+                if let Some(full_traceback) = full_traceback {
+                    let traceback = traceback.trim_start_matches("stack traceback:");
+                    let traceback = traceback.trim_start().trim_end();
+                    // Try to find local traceback within the full traceback
+                    if let Some(pos) = full_traceback.find(traceback) {
+                        write!(fmt, "{}", &full_traceback[..pos])?;
+                        writeln!(fmt, ">{}", &full_traceback[pos..].trim_end())?;
+                    } else {
+                        writeln!(fmt, "{}", full_traceback.trim_end())?;
+                    }
+                } else {
+                    writeln!(fmt, "{}", traceback.trim_end())?;
+                }
+                Ok(())
+            }
+            Error::PreviouslyResumedPanic => {
+                write!(fmt, "previously resumed panic returned again")
+            }
+            #[cfg(feature = "serde")]
+            Error::SerializeError(err) => {
+                write!(fmt, "serialize error: {err}")
+            },
+            #[cfg(feature = "serde")]
+            Error::DeserializeError(err) => {
+                write!(fmt, "deserialize error: {err}")
+            },
+            Error::ExternalError(err) => err.fmt(fmt),
+            Error::WithContext { context, cause } => {
+                writeln!(fmt, "{context}")?;
+                write!(fmt, "{cause}")
             }
-            Error::ExternalError(ref err) => write!(fmt, "external error: {}", err),
         }
     }
 }
 
 impl StdError for Error {
     fn source(&self) -> Option<&(dyn StdError + 'static)> {
-        match *self {
-            Error::CallbackError { ref cause, .. } => Some(cause.as_ref()),
-            Error::ExternalError(ref err) => Some(err.as_ref()),
+        match self {
+            // An error type with a source error should either return that error via source or
+            // include that source's error message in its own Display output, but never both.
+            // https://blog.rust-lang.org/inside-rust/2021/07/01/What-the-error-handling-project-group-is-working-towards.html
+            // Given that we include source to fmt::Display implementation for `CallbackError`, this call
+            // returns nothing.
+            Error::CallbackError { .. } => None,
+            Error::ExternalError(err) => err.source(),
+            Error::WithContext { cause, .. } => Self::source(cause),
             _ => None,
         }
     }
 }
 
 impl Error {
-    pub fn external<T: Into<Box<dyn StdError + Send + Sync>>>(err: T) -> Error {
+    /// Creates a new `RuntimeError` with the given message.
+    #[inline]
+    pub fn runtime<S: fmt::Display>(message: S) -> Self {
+        Error::RuntimeError(message.to_string())
+    }
+
+    /// Wraps an external error object.
+    #[inline]
+    pub fn external<T: Into<Box<DynStdError>>>(err: T) -> Self {
         Error::ExternalError(err.into().into())
     }
+
+    /// Attempts to downcast the external error object to a concrete type by reference.
+    pub fn downcast_ref<T>(&self) -> Option<&T>
+    where
+        T: StdError + 'static,
+    {
+        match self {
+            Error::ExternalError(err) => err.downcast_ref(),
+            Error::WithContext { cause, .. } => Self::downcast_ref(cause),
+            _ => None,
+        }
+    }
+
+    /// An iterator over the chain of nested errors wrapped by this Error.
+    pub fn chain(&self) -> impl Iterator<Item = &(dyn StdError + 'static)> {
+        Chain {
+            root: self,
+            current: None,
+        }
+    }
+
+    /// Returns the parent of this error.
+    #[doc(hidden)]
+    pub fn parent(&self) -> Option<&Error> {
+        match self {
+            Error::CallbackError { cause, .. } => Some(cause.as_ref()),
+            Error::WithContext { cause, .. } => Some(cause.as_ref()),
+            _ => None,
+        }
+    }
+
+    pub(crate) fn bad_self_argument(to: &str, cause: Error) -> Self {
+        Error::BadArgument {
+            to: Some(to.to_string()),
+            pos: 1,
+            name: Some("self".to_string()),
+            cause: Arc::new(cause),
+        }
+    }
+
+    pub(crate) fn from_lua_conversion(
+        from: &'static str,
+        to: impl ToString,
+        message: impl Into<Option<String>>,
+    ) -> Self {
+        Error::FromLuaConversionError {
+            from,
+            to: to.to_string(),
+            message: message.into(),
+        }
+    }
 }
 
+/// Trait for converting [`std::error::Error`] into Lua [`Error`].
 pub trait ExternalError {
-    fn to_lua_err(self) -> Error;
+    fn into_lua_err(self) -> Error;
 }
 
-impl<E> ExternalError for E
-where
-    E: Into<Box<dyn StdError + Send + Sync>>,
-{
-    fn to_lua_err(self) -> Error {
+impl<E: Into<Box<DynStdError>>> ExternalError for E {
+    fn into_lua_err(self) -> Error {
         Error::external(self)
     }
 }
 
+/// Trait for converting [`std::result::Result`] into Lua [`Result`].
 pub trait ExternalResult<T> {
-    fn to_lua_err(self) -> Result<T>;
+    fn into_lua_err(self) -> Result<T>;
 }
 
 impl<T, E> ExternalResult<T> for StdResult<T, E>
 where
     E: ExternalError,
 {
-    fn to_lua_err(self) -> Result<T> {
-        self.map_err(|e| e.to_lua_err())
+    fn into_lua_err(self) -> Result<T> {
+        self.map_err(|e| e.into_lua_err())
     }
 }
+
+/// Provides the `context` method for [`Error`] and `Result<T, Error>`.
+pub trait ErrorContext: Sealed {
+    /// Wraps the error value with additional context.
+    fn context<C: fmt::Display>(self, context: C) -> Self;
+
+    /// Wrap the error value with additional context that is evaluated lazily
+    /// only once an error does occur.
+    fn with_context<C: fmt::Display>(self, f: impl FnOnce(&Error) -> C) -> Self;
+}
+
+impl ErrorContext for Error {
+    fn context<C: fmt::Display>(self, context: C) -> Self {
+        let context = context.to_string();
+        match self {
+            Error::WithContext { cause, .. } => Error::WithContext { context, cause },
+            _ => Error::WithContext {
+                context,
+                cause: Arc::new(self),
+            },
+        }
+    }
+
+    fn with_context<C: fmt::Display>(self, f: impl FnOnce(&Error) -> C) -> Self {
+        let context = f(&self).to_string();
+        match self {
+            Error::WithContext { cause, .. } => Error::WithContext { context, cause },
+            _ => Error::WithContext {
+                context,
+                cause: Arc::new(self),
+            },
+        }
+    }
+}
+
+impl<T> ErrorContext for Result<T> {
+    fn context<C: fmt::Display>(self, context: C) -> Self {
+        self.map_err(|err| err.context(context))
+    }
+
+    fn with_context<C: fmt::Display>(self, f: impl FnOnce(&Error) -> C) -> Self {
+        self.map_err(|err| err.with_context(f))
+    }
+}
+
+impl From<AddrParseError> for Error {
+    fn from(err: AddrParseError) -> Self {
+        Error::external(err)
+    }
+}
+
+impl From<IoError> for Error {
+    fn from(err: IoError) -> Self {
+        Error::external(err)
+    }
+}
+
+impl From<Utf8Error> for Error {
+    fn from(err: Utf8Error) -> Self {
+        Error::external(err)
+    }
+}
+
+#[cfg(feature = "serde")]
+impl serde::ser::Error for Error {
+    fn custom<T: fmt::Display>(msg: T) -> Self {
+        Self::SerializeError(msg.to_string())
+    }
+}
+
+#[cfg(feature = "serde")]
+impl serde::de::Error for Error {
+    fn custom<T: fmt::Display>(msg: T) -> Self {
+        Self::DeserializeError(msg.to_string())
+    }
+}
+
+#[cfg(feature = "anyhow")]
+impl From<anyhow::Error> for Error {
+    fn from(err: anyhow::Error) -> Self {
+        match err.downcast::<Self>() {
+            Ok(err) => err,
+            Err(err) => Error::external(err),
+        }
+    }
+}
+
+struct Chain<'a> {
+    root: &'a Error,
+    current: Option<&'a (dyn StdError + 'static)>,
+}
+
+impl<'a> Iterator for Chain<'a> {
+    type Item = &'a (dyn StdError + 'static);
+
+    fn next(&mut self) -> Option<Self::Item> {
+        loop {
+            let error: Option<&dyn StdError> = match self.current {
+                None => {
+                    self.current = Some(self.root);
+                    self.current
+                }
+                Some(current) => match current.downcast_ref::<Error>()? {
+                    Error::BadArgument { cause, .. }
+                    | Error::CallbackError { cause, .. }
+                    | Error::WithContext { cause, .. } => {
+                        self.current = Some(&**cause);
+                        self.current
+                    }
+                    Error::ExternalError(err) => {
+                        self.current = Some(&**err);
+                        self.current
+                    }
+                    _ => None,
+                },
+            };
+
+            // Skip `ExternalError` as it only wraps the underlying error
+            // without meaningful context
+            if let Some(Error::ExternalError(_)) = error?.downcast_ref::<Error>() {
+                continue;
+            }
+
+            return self.current;
+        }
+    }
+}
+
+#[cfg(test)]
+mod assertions {
+    use super::*;
+
+    #[cfg(not(feature = "error-send"))]
+    static_assertions::assert_not_impl_any!(Error: Send, Sync);
+    #[cfg(feature = "send")]
+    static_assertions::assert_impl_all!(Error: Send, Sync);
+}

src/ffi/compat53.rs

@@ -1,798 +0,0 @@
-// The MIT License (MIT)
-//
-// Copyright (c) 2019 A. Orlenko
-//
-// Permission is hereby granted, free of charge, to any person obtaining a copy
-// of this software and associated documentation files (the "Software"), to deal
-// in the Software without restriction, including without limitation the rights
-// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-// copies of the Software, and to permit persons to whom the Software is
-// furnished to do so, subject to the following conditions:
-//
-// The above copyright notice and this permission notice shall be included in
-// all copies or substantial portions of the Software.
-//
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-// THE SOFTWARE.
-
-// Based on github.com/keplerproject/lua-compat-5.3
-
-use std::ffi::CStr;
-use std::mem;
-use std::os::raw::{c_char, c_int, c_void};
-use std::ptr;
-
-use super::lauxlib::{
-    luaL_callmeta, luaL_error, luaL_getmetafield_old, luaL_loadbuffer, luaL_newmetatable_old,
-};
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-use super::lauxlib::{luaL_Reg, luaL_checktype, luaL_getmetatable};
-
-#[cfg(feature = "lua52")]
-use super::lauxlib::{luaL_checkstack, luaL_getsubtable};
-
-use super::lua::{
-    self, lua_CFunction, lua_Debug, lua_Integer, lua_Number, lua_State, lua_Writer, lua_call,
-    lua_createtable, lua_dump_old, lua_error, lua_getfield_old, lua_getstack, lua_gettable_old,
-    lua_gettop, lua_insert, lua_isstring, lua_istable, lua_newuserdata, lua_pop, lua_pushboolean,
-    lua_pushcfunction, lua_pushfstring, lua_pushinteger, lua_pushliteral, lua_pushlstring_old,
-    lua_pushnumber, lua_pushthread, lua_pushvalue, lua_rawget_old, lua_rawgeti_old, lua_rawset,
-    lua_replace, lua_setfield, lua_setglobal, lua_setmetatable, lua_settable, lua_toboolean,
-    lua_tointeger, lua_tolstring, lua_tonumber, lua_topointer, lua_tostring, lua_touserdata,
-    lua_type, lua_typename,
-};
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-use super::lua::{
-    lua_checkstack, lua_concat, lua_equal, lua_getfenv, lua_getinfo, lua_getmetatable,
-    lua_isnumber, lua_lessthan, lua_newtable, lua_next, lua_objlen, lua_pushcclosure,
-    lua_pushlightuserdata, lua_pushnil, lua_pushstring_old, lua_rawequal, lua_remove,
-    lua_resume_old, lua_setfenv, lua_settop, LUA_OPADD, LUA_OPUNM,
-};
-
-#[cfg(feature = "lua52")]
-use super::lua::{
-    lua_absindex, lua_getglobal_old, lua_getuservalue_old, lua_pushstring, lua_rawgetp_old,
-    lua_rawsetp, lua_tonumberx,
-};
-
-unsafe fn compat53_reverse(L: *mut lua_State, mut a: c_int, mut b: c_int) {
-    while a < b {
-        lua_pushvalue(L, a);
-        lua_pushvalue(L, b);
-        lua_replace(L, a);
-        lua_replace(L, b);
-        a += 1;
-        b -= 1;
-    }
-}
-
-const COMPAT53_LEVELS1: c_int = 12; // size of the first part of the stack
-const COMPAT53_LEVELS2: c_int = 10; // size of the second part of the stack
-
-unsafe fn compat53_countlevels(L: *mut lua_State) -> c_int {
-    let mut ar: lua_Debug = mem::zeroed();
-    let (mut li, mut le) = (1, 1);
-    // find an upper bound
-    while lua_getstack(L, le, &mut ar) != 0 {
-        li = le;
-        le *= 2;
-    }
-    // do a binary search
-    while li < le {
-        let m = (li + le) / 2;
-        if lua_getstack(L, m, &mut ar) != 0 {
-            li = m + 1
-        } else {
-            le = m;
-        }
-    }
-    le - 1
-}
-
-unsafe fn compat53_checkmode(
-    L: *mut lua_State,
-    mode: *const c_char,
-    modename: *const c_char,
-    err: c_int,
-) -> c_int {
-    unsafe fn strchr(s: *const c_char, c: c_char) -> *const c_char {
-        let mut st = s;
-        while *st != 0 && *st != c {
-            st = st.offset(1);
-        }
-        if *st == c {
-            st
-        } else {
-            ptr::null()
-        }
-    }
-
-    if mode != ptr::null() && strchr(mode, *modename) == ptr::null() {
-        lua_pushfstring(
-            L,
-            cstr!("attempt to load a %s chunk (mode is '%s')"),
-            modename,
-            mode,
-        );
-        return err;
-    }
-    lua::LUA_OK
-}
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-unsafe fn compat53_findfield(L: *mut lua_State, objidx: c_int, level: c_int) -> c_int {
-    if level == 0 || lua_istable(L, -1) == 0 {
-        return 0; // not found
-    }
-
-    lua_pushnil(L); // start 'next' loop
-    while lua_next(L, -2) != 0 {
-        // for each pair in table
-        if lua_type(L, -2) == lua::LUA_TSTRING {
-            // ignore non-string keys
-            if lua_rawequal(L, objidx, -1) != 0 {
-                // found object?
-                lua_pop(L, 1); // remove value (but keep name)
-                return 1;
-            } else if compat53_findfield(L, objidx, level - 1) != 0 {
-                // try recursively
-                lua_remove(L, -2); // remove table (but keep name)
-                lua_pushliteral(L, ".");
-                lua_insert(L, -2); // place '.' between the two names
-                lua_concat(L, 3);
-                return 1;
-            }
-        }
-        lua_pop(L, 1); // remove value
-    }
-    return 0; // not found
-}
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-unsafe fn compat53_pushglobalfuncname(L: *mut lua_State, ar: *mut lua_Debug) -> c_int {
-    let top = lua_gettop(L);
-    lua_getinfo(L, cstr!("f"), ar); // push function
-    lua_pushvalue(L, lua::LUA_GLOBALSINDEX);
-    if compat53_findfield(L, top + 1, 2) != 0 {
-        lua_copy(L, -1, top + 1); // move name to proper place
-        lua_pop(L, 2); // remove pushed values
-        return 1;
-    } else {
-        lua_settop(L, top); // remove function and global table
-        return 0;
-    }
-}
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-unsafe fn compat53_pushfuncname(L: *mut lua_State, ar: *mut lua_Debug) {
-    if *(*ar).namewhat != b'\0' as c_char {
-        // is there a name?
-        lua_pushfstring(L, cstr!("function '%s'"), (*ar).name);
-    } else if *(*ar).what == b'm' as c_char {
-        // main?
-        lua_pushliteral(L, "main chunk");
-    } else if *(*ar).what == b'C' as c_char {
-        if compat53_pushglobalfuncname(L, ar) != 0 {
-            lua_pushfstring(L, cstr!("function '%s'"), lua_tostring(L, -1));
-            lua_remove(L, -2); // remove name
-        } else {
-            lua_pushliteral(L, "?");
-        }
-    } else {
-        lua_pushfstring(
-            L,
-            cstr!("function <%s:%d>"),
-            (*ar).short_src.as_ptr(),
-            (*ar).linedefined,
-        );
-    }
-}
-
-unsafe fn compat53_call_lua(L: *mut lua_State, code: &str, nargs: c_int, nret: c_int) {
-    lua_rawgetp(L, lua::LUA_REGISTRYINDEX, code.as_ptr() as *const c_void);
-    if lua_type(L, -1) != lua::LUA_TFUNCTION {
-        lua_pop(L, 1);
-        if luaL_loadbuffer(
-            L,
-            code.as_ptr() as *const c_char,
-            code.as_bytes().len(),
-            cstr!("=none"),
-        ) != 0
-        {
-            lua_error(L);
-        }
-        lua_pushvalue(L, -1);
-        lua_rawsetp(L, lua::LUA_REGISTRYINDEX, code.as_ptr() as *const c_void);
-    }
-    lua_insert(L, -nargs - 1);
-    lua_call(L, nargs, nret);
-}
-
-//
-// lua ported functions
-//
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-#[inline(always)]
-pub fn lua_upvalueindex(i: c_int) -> c_int {
-    lua::LUA_GLOBALSINDEX - i
-}
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-pub unsafe fn lua_absindex(L: *mut lua_State, mut idx: c_int) -> c_int {
-    if idx < 0 && idx > lua::LUA_REGISTRYINDEX {
-        idx += lua_gettop(L) + 1;
-    }
-    idx
-}
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-static COMPAT53_ARITH_CODE: &'static str = r#"
-local op,a,b=...
-if op == 0 then return a+b
-elseif op == 1 then return a-b
-elseif op == 2 then return a*b
-elseif op == 3 then return a/b
-elseif op == 4 then return a%b
-elseif op == 5 then return a^b
-elseif op == 6 then return -a
-end
-"#;
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-pub unsafe fn lua_arith(L: *mut lua_State, op: c_int) {
-    if op < LUA_OPADD || op > LUA_OPUNM {
-        luaL_error(L, cstr!("invalid 'op' argument for lua_arith"));
-    }
-    luaL_checkstack(L, 5, cstr!("not enough stack slots"));
-    if op == LUA_OPUNM {
-        lua_pushvalue(L, -1);
-    }
-    lua_pushnumber(L, op as lua_Number);
-    lua_insert(L, -3);
-    compat53_call_lua(L, COMPAT53_ARITH_CODE, 3, 1);
-}
-
-pub unsafe fn lua_rotate(L: *mut lua_State, mut idx: c_int, mut n: c_int) {
-    idx = lua_absindex(L, idx);
-    let n_elems = lua_gettop(L) - idx + 1;
-    if n < 0 {
-        n += n_elems;
-    }
-    if n > 0 && n < n_elems {
-        luaL_checkstack(L, 2, cstr!("not enough stack slots available"));
-        n = n_elems - n;
-        compat53_reverse(L, idx, idx + n - 1);
-        compat53_reverse(L, idx + n, idx + n_elems - 1);
-        compat53_reverse(L, idx, idx + n_elems - 1);
-    }
-}
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-pub unsafe fn lua_copy(L: *mut lua_State, fromidx: c_int, toidx: c_int) {
-    let abs_to = lua_absindex(L, toidx);
-    luaL_checkstack(L, 1, cstr!("not enough stack slots"));
-    lua_pushvalue(L, fromidx);
-    lua_replace(L, abs_to);
-}
-
-pub unsafe fn lua_isinteger(L: *mut lua_State, idx: c_int) -> c_int {
-    if lua_type(L, idx) == lua::LUA_TNUMBER {
-        let n = lua_tonumber(L, idx);
-        let i = lua_tointeger(L, idx);
-        if i as f64 == n {
-            return 1;
-        }
-    }
-    return 0;
-}
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-pub unsafe fn lua_tonumberx(L: *mut lua_State, i: c_int, isnum: *mut c_int) -> lua_Number {
-    let n = lua_tonumber(L, i);
-    if isnum != ptr::null_mut() {
-        *isnum = if n != 0.0 || lua_isnumber(L, i) != 0 {
-            1
-        } else {
-            0
-        };
-    }
-    return n;
-}
-
-// Implemented for Lua 5.2 as well
-// See https://github.com/keplerproject/lua-compat-5.3/issues/40
-pub unsafe fn lua_tointegerx(L: *mut lua_State, i: c_int, isnum: *mut c_int) -> lua_Integer {
-    let mut ok = 0;
-    let n = lua_tonumberx(L, i, &mut ok);
-    if ok != 0 {
-        if n == n as lua_Integer as lua_Number {
-            if isnum != ptr::null_mut() {
-                *isnum = 1;
-            }
-            return n as lua_Integer;
-        }
-    }
-    if isnum != ptr::null_mut() {
-        *isnum = 0;
-    }
-    return 0;
-}
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-pub unsafe fn lua_rawlen(L: *mut lua_State, idx: c_int) -> usize {
-    lua_objlen(L, idx)
-}
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-pub unsafe fn lua_compare(L: *mut lua_State, mut idx1: c_int, mut idx2: c_int, op: c_int) -> c_int {
-    match op {
-        lua::LUA_OPEQ => lua_equal(L, idx1, idx2),
-        lua::LUA_OPLT => lua_lessthan(L, idx1, idx2),
-        lua::LUA_OPLE => {
-            luaL_checkstack(L, 5, cstr!("not enough stack slots"));
-            idx1 = lua_absindex(L, idx1);
-            idx2 = lua_absindex(L, idx2);
-            lua_pushvalue(L, idx1);
-            lua_pushvalue(L, idx2);
-            compat53_call_lua(L, "local a,b=...\nreturn a<=b\n", 2, 1);
-            let result = lua_toboolean(L, -1);
-            lua_pop(L, 1);
-            result
-        }
-        _ => luaL_error(L, cstr!("invalid 'op' argument for lua_compare")),
-    }
-}
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-pub unsafe fn lua_pushlstring(L: *mut lua_State, s: *const c_char, l: usize) -> *const c_char {
-    if l == 0 {
-        lua_pushlstring_old(L, cstr!(""), 0);
-    } else {
-        lua_pushlstring_old(L, s, l);
-    }
-    lua_tostring(L, -1)
-}
-
-#[cfg(feature = "lua52")]
-pub unsafe fn lua_pushlstring(L: *mut lua_State, s: *const c_char, l: usize) -> *const c_char {
-    if l == 0 {
-        lua_pushlstring_old(L, cstr!(""), 0)
-    } else {
-        lua_pushlstring_old(L, s, l)
-    }
-}
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-pub unsafe fn lua_pushstring(L: *mut lua_State, s: *const c_char) -> *const c_char {
-    lua_pushstring_old(L, s);
-    lua_tostring(L, -1)
-}
-
-#[cfg(feature = "lua52")]
-pub unsafe fn lua_getglobal(L: *mut lua_State, var: *const c_char) -> c_int {
-    lua_getglobal_old(L, var);
-    lua_type(L, -1)
-}
-
-pub unsafe fn lua_gettable(L: *mut lua_State, idx: c_int) -> c_int {
-    lua_gettable_old(L, idx);
-    lua_type(L, -1)
-}
-
-pub unsafe fn lua_getfield(L: *mut lua_State, idx: c_int, k: *const c_char) -> c_int {
-    lua_getfield_old(L, idx, k);
-    lua_type(L, -1)
-}
-
-pub unsafe fn lua_geti(L: *mut lua_State, mut idx: c_int, n: lua_Integer) -> c_int {
-    idx = lua_absindex(L, idx);
-    lua_pushinteger(L, n);
-    lua_gettable(L, idx);
-    lua_type(L, -1)
-}
-
-// A new version which returns c_int
-pub unsafe fn lua_rawget(L: *mut lua_State, idx: c_int) -> c_int {
-    lua_rawget_old(L, idx);
-    lua_type(L, -1)
-}
-
-// A new version which returns c_int
-pub unsafe fn lua_rawgeti(L: *mut lua_State, idx: c_int, n: lua_Integer) -> c_int {
-    lua_rawgeti_old(L, idx, n);
-    lua_type(L, -1)
-}
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-pub unsafe fn lua_rawgetp(L: *mut lua_State, idx: c_int, p: *const c_void) -> c_int {
-    let abs_i = lua_absindex(L, idx);
-    lua_pushlightuserdata(L, p as *mut c_void);
-    lua_rawget(L, abs_i);
-    lua_type(L, -1)
-}
-
-#[cfg(feature = "lua52")]
-pub unsafe fn lua_rawgetp(L: *mut lua_State, idx: c_int, p: *const c_void) -> c_int {
-    lua_rawgetp_old(L, idx, p);
-    lua_type(L, -1)
-}
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-pub unsafe fn lua_getuservalue(L: *mut lua_State, idx: c_int) -> c_int {
-    lua_getfenv(L, idx);
-    lua_type(L, -1)
-}
-
-#[cfg(feature = "lua52")]
-pub unsafe fn lua_getuservalue(L: *mut lua_State, idx: c_int) -> c_int {
-    lua_getuservalue_old(L, idx);
-    lua_type(L, -1)
-}
-
-pub unsafe fn lua_seti(L: *mut lua_State, mut idx: c_int, n: lua_Integer) {
-    luaL_checkstack(L, 1, cstr!("not enough stack slots available"));
-    idx = lua_absindex(L, idx);
-    lua_pushinteger(L, n);
-    lua_insert(L, -2);
-    lua_settable(L, idx);
-}
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-pub unsafe fn lua_rawsetp(L: *mut lua_State, idx: c_int, p: *const c_void) {
-    let abs_i = lua_absindex(L, idx);
-    luaL_checkstack(L, 1, cstr!("not enough stack slots"));
-    lua_pushlightuserdata(L, p as *mut c_void);
-    lua_insert(L, -2);
-    lua_rawset(L, abs_i);
-}
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-pub unsafe fn lua_setuservalue(L: *mut lua_State, idx: c_int) {
-    luaL_checktype(L, -1, lua::LUA_TTABLE);
-    lua_setfenv(L, idx);
-}
-
-pub unsafe fn lua_dump(
-    L: *mut lua_State,
-    writer: lua_Writer,
-    data: *mut c_void,
-    _strip: c_int,
-) -> c_int {
-    lua_dump_old(L, writer, data)
-}
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-pub unsafe fn lua_resume(L: *mut lua_State, _from: *mut lua_State, narg: c_int) -> c_int {
-    lua_resume_old(L, narg)
-}
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-pub unsafe fn lua_len(L: *mut lua_State, idx: c_int) {
-    match lua_type(L, idx) {
-        lua::LUA_TSTRING => {
-            lua_pushnumber(L, lua_objlen(L, idx) as lua_Number);
-        }
-        lua::LUA_TTABLE => {
-            if luaL_callmeta(L, idx, cstr!("__len")) == 0 {
-                lua_pushnumber(L, lua_objlen(L, idx) as lua_Number);
-            }
-        }
-        lua::LUA_TUSERDATA if luaL_callmeta(L, idx, cstr!("__len")) != 0 => {}
-        _ => {
-            luaL_error(
-                L,
-                cstr!("attempt to get length of a %s value"),
-                lua_typename(L, lua_type(L, idx)),
-            );
-        }
-    }
-}
-
-pub unsafe fn lua_stringtonumber(L: *mut lua_State, s: *const c_char) -> usize {
-    use std::str::FromStr;
-
-    let cs = CStr::from_ptr(s);
-    if let Ok(rs) = cs.to_str() {
-        if let Ok(n) = f64::from_str(rs.trim()) {
-            lua_pushnumber(L, n as lua_Number);
-            return cs.to_bytes_with_nul().len();
-        }
-    }
-    0
-}
-
-pub unsafe fn lua_getextraspace(L: *mut lua_State) -> *mut c_void {
-    use super::glue::LUA_EXTRASPACE;
-
-    luaL_checkstack(L, 4, cstr!("not enough stack slots available"));
-    lua_pushliteral(L, "__compat53_extraspace");
-    lua_pushvalue(L, -1);
-    lua_rawget(L, lua::LUA_REGISTRYINDEX);
-    if lua_istable(L, -1) == 0 {
-        lua_pop(L, 1);
-        lua_createtable(L, 0, 2);
-        lua_createtable(L, 0, 1);
-        lua_pushliteral(L, "k");
-        lua_setfield(L, -2, cstr!("__mode"));
-        lua_setmetatable(L, -2);
-        lua_pushvalue(L, -2);
-        lua_pushvalue(L, -2);
-        lua_rawset(L, lua::LUA_REGISTRYINDEX);
-    }
-    lua_replace(L, -2);
-    let is_main = lua_pushthread(L);
-    lua_rawget(L, -2);
-    let mut _ptr = lua_touserdata(L, -1);
-    if _ptr == ptr::null_mut() {
-        lua_pop(L, 1);
-        _ptr = lua_newuserdata(L, LUA_EXTRASPACE as usize);
-        if is_main != 0 {
-            // mem::size_of::<c_void>() == 1
-            ptr::write_bytes(_ptr, 0, LUA_EXTRASPACE as usize);
-            lua_pushthread(L);
-            lua_pushvalue(L, -2);
-            lua_rawset(L, -4);
-            lua_pushboolean(L, 1);
-            lua_pushvalue(L, -2);
-            lua_rawset(L, -4);
-        } else {
-            lua_pushboolean(L, 1);
-            lua_rawget(L, -3);
-            let mptr = lua_touserdata(L, -1);
-            if mptr != ptr::null_mut() {
-                ptr::copy_nonoverlapping(mptr, _ptr, LUA_EXTRASPACE as usize)
-            } else {
-                ptr::write_bytes(_ptr, 0, LUA_EXTRASPACE as usize);
-            }
-            lua_pop(L, 1);
-            lua_pushthread(L);
-            lua_pushvalue(L, -2);
-            lua_rawset(L, -4);
-        }
-    }
-    lua_pop(L, 2);
-    return _ptr;
-}
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-#[inline(always)]
-pub unsafe fn lua_pushglobaltable(L: *mut lua_State) {
-    lua_pushvalue(L, lua::LUA_GLOBALSINDEX);
-}
-
-//
-// lauxlib ported functions
-//
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-pub unsafe fn luaL_checkstack(L: *mut lua_State, sz: c_int, msg: *const c_char) {
-    if lua_checkstack(L, sz + lua::LUA_MINSTACK) == 0 {
-        if msg != ptr::null() {
-            luaL_error(L, cstr!("stack overflow (%s)"), msg);
-        } else {
-            lua_pushliteral(L, "stack overflow");
-            lua_error(L);
-        }
-    }
-}
-
-pub unsafe fn luaL_checkversion(_L: *mut lua_State) {
-    // Void
-}
-
-pub unsafe fn luaL_getmetafield(L: *mut lua_State, obj: c_int, e: *const c_char) -> c_int {
-    if luaL_getmetafield_old(L, obj, e) != 0 {
-        lua_type(L, -1)
-    } else {
-        lua::LUA_TNIL
-    }
-}
-
-pub unsafe fn luaL_newmetatable(L: *mut lua_State, tname: *const c_char) -> c_int {
-    if luaL_newmetatable_old(L, tname) != 0 {
-        lua_pushstring(L, tname);
-        lua_setfield(L, -2, cstr!("__name"));
-        1
-    } else {
-        0
-    }
-}
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-pub unsafe fn luaL_loadbufferx(
-    L: *mut lua_State,
-    buff: *const c_char,
-    sz: usize,
-    name: *const c_char,
-    mode: *const c_char,
-) -> c_int {
-    let status = if sz > 0 && *buff as u8 == lua::LUA_SIGNATURE[0] {
-        compat53_checkmode(L, mode, cstr!("binary"), lua::LUA_ERRSYNTAX)
-    } else {
-        compat53_checkmode(L, mode, cstr!("text"), lua::LUA_ERRSYNTAX)
-    };
-    if status != lua::LUA_OK {
-        return status;
-    }
-    luaL_loadbuffer(L, buff, sz, name)
-}
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-pub unsafe fn luaL_len(L: *mut lua_State, idx: c_int) -> lua_Integer {
-    let mut isnum = 0;
-    luaL_checkstack(L, 1, cstr!("not enough stack slots"));
-    lua_len(L, idx);
-    let res = lua_tointegerx(L, -1, &mut isnum);
-    lua::lua_pop(L, 1);
-    if isnum == 0 {
-        luaL_error(L, cstr!("object length is not an integer"));
-    }
-    res
-}
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-pub unsafe fn luaL_traceback(
-    L: *mut lua_State,
-    L1: *mut lua_State,
-    msg: *const c_char,
-    mut level: c_int,
-) {
-    let mut ar: lua_Debug = std::mem::zeroed();
-    let top = lua_gettop(L);
-    let numlevels = compat53_countlevels(L1);
-    let mark = if numlevels > COMPAT53_LEVELS1 + COMPAT53_LEVELS2 {
-        COMPAT53_LEVELS1
-    } else {
-        0
-    };
-
-    if msg != ptr::null() {
-        lua_pushfstring(L, cstr!("%s\n"), msg);
-    }
-    lua_pushliteral(L, "stack traceback:");
-    while lua_getstack(L1, level, &mut ar) != 0 {
-        level += 1;
-        if level == mark {
-            // too many levels?
-            lua_pushliteral(L, "\n\t..."); // add a '...'
-            level = numlevels - COMPAT53_LEVELS2; // and skip to last ones
-        } else {
-            lua_getinfo(L1, cstr!("Slnt"), &mut ar);
-            lua_pushfstring(L, cstr!("\n\t%s:"), cstr!("ok") /*ar.short_src*/);
-            if ar.currentline > 0 {
-                lua_pushfstring(L, cstr!("%d:"), ar.currentline);
-            }
-            lua_pushliteral(L, " in ");
-            compat53_pushfuncname(L, &mut ar);
-            lua_concat(L, lua_gettop(L) - top);
-        }
-    }
-    lua_concat(L, lua_gettop(L) - top);
-}
-
-pub unsafe fn luaL_tolstring(L: *mut lua_State, idx: c_int, len: *mut usize) -> *const c_char {
-    if luaL_callmeta(L, idx, cstr!("__tostring")) == 0 {
-        let t = lua_type(L, idx);
-        match t {
-            lua::LUA_TNIL => {
-                lua_pushliteral(L, "nil");
-            }
-            lua::LUA_TSTRING | lua::LUA_TNUMBER => {
-                lua_pushvalue(L, idx);
-            }
-            lua::LUA_TBOOLEAN => {
-                if lua_toboolean(L, idx) == 0 {
-                    lua_pushliteral(L, "false");
-                } else {
-                    lua_pushliteral(L, "true");
-                }
-            }
-            _ => {
-                let tt = luaL_getmetafield(L, idx, cstr!("__name"));
-                let name = if tt == lua::LUA_TSTRING {
-                    lua_tostring(L, -1)
-                } else {
-                    lua_typename(L, t)
-                };
-                lua_pushfstring(L, cstr!("%s: %p"), name, lua_topointer(L, idx));
-                if tt != lua::LUA_TNIL {
-                    lua_replace(L, -2);
-                }
-            }
-        };
-    } else {
-        if lua_isstring(L, -1) == 0 {
-            luaL_error(L, cstr!("'__tostring' must return a string"));
-        }
-    }
-    lua_tolstring(L, -1, len)
-}
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-pub unsafe fn luaL_setmetatable(L: *mut lua_State, tname: *const c_char) {
-    luaL_checkstack(L, 1, cstr!("not enough stack slots"));
-    luaL_getmetatable(L, tname);
-    lua_setmetatable(L, -2);
-}
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-pub unsafe fn luaL_testudata(L: *mut lua_State, i: c_int, tname: *const c_char) -> *mut c_void {
-    let mut p = lua_touserdata(L, i);
-    luaL_checkstack(L, 2, cstr!("not enough stack slots"));
-    if p == ptr::null_mut() || lua_getmetatable(L, i) == 0 {
-        return ptr::null_mut();
-    } else {
-        luaL_getmetatable(L, tname);
-        let res = lua_rawequal(L, -1, -2);
-        lua_pop(L, 2);
-        if res == 0 {
-            p = ptr::null_mut();
-        }
-    }
-    return p;
-}
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-pub unsafe fn luaL_setfuncs(L: *mut lua_State, mut l: *const luaL_Reg, nup: c_int) {
-    luaL_checkstack(L, nup + 1, cstr!("too many upvalues"));
-    while (*l).name != ptr::null() {
-        // fill the table with given functions
-        l = l.offset(1);
-        lua_pushstring(L, (*l).name);
-        for _ in 0..nup {
-            // copy upvalues to the top
-            lua_pushvalue(L, -(nup + 1));
-        }
-        lua_pushcclosure(L, (*l).func, nup); // closure with those upvalues
-        lua_settable(L, -(nup + 3)); // table must be below the upvalues, the name and the closure
-    }
-    lua_pop(L, nup); // remove upvalues
-}
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-pub unsafe fn luaL_getsubtable(L: *mut lua_State, idx: c_int, fname: *const c_char) -> c_int {
-    let abs_i = lua_absindex(L, idx);
-    luaL_checkstack(L, 3, cstr!("not enough stack slots"));
-    lua_pushstring(L, fname);
-    lua_gettable(L, abs_i);
-    if lua_istable(L, -1) != 0 {
-        return 1;
-    }
-    lua_pop(L, 1);
-    lua_newtable(L);
-    lua_pushstring(L, fname);
-    lua_pushvalue(L, -2);
-    lua_settable(L, abs_i);
-    return 0;
-}
-
-pub unsafe fn luaL_requiref(
-    L: *mut lua_State,
-    modname: *const c_char,
-    openf: lua_CFunction,
-    glb: c_int,
-) {
-    luaL_checkstack(L, 3, cstr!("not enough stack slots available"));
-    luaL_getsubtable(L, lua::LUA_REGISTRYINDEX, cstr!("_LOADED"));
-    if lua_getfield(L, -1, modname) == lua::LUA_TNIL {
-        lua_pop(L, 1);
-        lua_pushcfunction(L, openf);
-        lua_pushstring(L, modname);
-        lua_call(L, 1, 1);
-        lua_pushvalue(L, -1);
-        lua_setfield(L, -3, modname);
-    }
-    if glb != 0 {
-        lua_pushvalue(L, -1);
-        lua_setglobal(L, modname);
-    }
-    lua_replace(L, -2);
-}

src/ffi/glue/glue.c

@@ -1,291 +0,0 @@
-// The MIT License (MIT)
-//
-// Copyright (c) 2019 A. Orlenko
-// Copyright (c) 2014 J.C. Moyer
-//
-// Permission is hereby granted, free of charge, to any person obtaining a copy
-// of this software and associated documentation files (the "Software"), to deal
-// in the Software without restriction, including without limitation the rights
-// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-// copies of the Software, and to permit persons to whom the Software is
-// furnished to do so, subject to the following conditions:
-//
-// The above copyright notice and this permission notice shall be included in
-// all copies or substantial portions of the Software.
-//
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-// THE SOFTWARE.
-
-#include <errno.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
-
-#include <lauxlib.h>
-#include <lua.h>
-#include <lualib.h>
-
-#ifndef LUA_EXTRASPACE
-#define LUA_EXTRASPACE (sizeof(void*))
-#endif
-
-// Macros taken from https://gcc.gnu.org/onlinedocs/cpp/Stringification.html
-#define xstr(s) str(s)
-#define str(s) #s
-
-typedef struct rs_item {
-  int type;
-  const char *name;
-  union {
-    int int_val;
-    const char *str_val;
-    LUA_INTEGER lua_int_val;
-  };
-} rs_item;
-
-
-#define TY_INT 0
-#define RS_INT(name, val)                                                      \
-  { TY_INT, name, .int_val = val }
-
-#if LUA_VERSION_NUM == 503
-#define TY_LUAINT 1
-#define RS_LUAINT(name, val)                                                   \
-  { TY_LUAINT, name, .lua_int_val = val }
-#endif
-
-#define TY_STR 2
-#define RS_STR(name, val)                                                      \
-  { TY_STR, name, .str_val = val }
-
-#define TY_TYPE 3
-#define RS_TYPE(name, val)                                                     \
-  { TY_TYPE, name, .str_val = val }
-
-#define TY_COMMENT 4
-#define RS_COMMENT(val)                                                        \
-  { TY_COMMENT, NULL, .str_val = val }
-
-#define TY_RAW 5
-#define RS_RAW(val)                                                            \
-  { TY_RAW, NULL, .str_val = val }
-
-const char *rs_int_type(int width) {
-  switch (width) {
-  default:
-  case 2:
-    return "i16";
-  case 4:
-    return "i32";
-  case 8:
-    return "i64";
-  }
-}
-
-const char *rs_uint_type(int width) {
-  switch (width) {
-  default:
-  case 2:
-    return "u16";
-  case 4:
-    return "u32";
-  case 8:
-    return "u64";
-  }
-}
-
-int try_write(char **str, char c, size_t n, size_t *written, size_t szstr) {
-  if (szstr - *written < n) {
-    return 0;
-  }
-  for (; n; n--, *written++)
-    *(*str)++ = c;
-  return 1;
-}
-
-// converts \ in a string to \\ so that it can be used as a rust string literal
-// ensures that `out` will always have a null terminating character
-size_t escape(const char *in, char *out, size_t szout) {
-  size_t written = 0;
-  char cur;
-
-  while ((cur = *in++)) {
-    switch (cur) {
-    case '\\':
-      if (!try_write(&out, cur, 2, &written, szout))
-        goto finalize;
-      break;
-    default:
-      if (!try_write(&out, cur, 1, &written, szout))
-        goto finalize;
-      break;
-    }
-  }
-
-finalize:
-  if (written + 1 <= szout) {
-    *out++ = '\0';
-    written++;
-  }
-  return written;
-}
-
-int write_int_item(FILE *f, const char *name, int value) {
-  return fprintf(f, "pub const %s: c_int = %d;\n", name, value);
-}
-
-#if LUA_VERSION_NUM == 503
-int write_lua_int_item(FILE *f, const char *name, LUA_INTEGER value) {
-  return fprintf(f, "pub const %s: LUA_INTEGER = " LUA_INTEGER_FMT ";\n", name,
-                 value);
-}
-#endif
-
-int write_str_item(FILE *f, const char *name, const char *value) {
-  size_t len = strlen(value);
-  size_t bufsz = len * 2 + 1;
-  char *buf = malloc(bufsz);
-  int ret;
-  escape(value, buf, bufsz);
-  ret = fprintf(f, "pub const %s: &'static str = \"%s\";\n", name, buf);
-  free(buf);
-  return ret;
-}
-
-int write_type(FILE *f, const char *name, const char *value) {
-  return fprintf(f, "pub type %s = %s;\n", name, value);
-}
-
-int write_comment(FILE *f, const char *value) {
-  return fprintf(f, "/* %s */\n", value);
-}
-
-int write_raw(FILE *f, const char *value) { return fputs(value, f) >= 0; }
-
-int write_item(FILE *f, const rs_item *c) {
-  switch (c->type) {
-  case TY_INT:
-    return write_int_item(f, c->name, c->int_val);
-#if LUA_VERSION_NUM == 503
-  case TY_LUAINT:
-    return write_lua_int_item(f, c->name, c->lua_int_val);
-#endif
-  case TY_STR:
-    return write_str_item(f, c->name, c->str_val);
-  case TY_TYPE:
-    return write_type(f, c->name, c->str_val);
-  case TY_COMMENT:
-    return write_comment(f, c->str_val);
-  case TY_RAW:
-    return write_raw(f, c->str_val);
-  default:
-    return 0;
-  }
-}
-
-int write_items_(FILE *f, const rs_item items[], size_t num) {
-  size_t i;
-  for (i = 0; i < num; i++) {
-    if (!write_item(f, &items[i]))
-      return 0;
-  }
-  return 1;
-}
-
-#define write_items(f, cs) write_items_(f, cs, sizeof(cs) / sizeof(cs[0]))
-
-int main(int argc, const char **argv) {
-  if (argc <= 1) {
-    printf("usage: %s <filename>\n", argv[0]);
-    return EXIT_FAILURE;
-  }
-
-  const char *filename = argv[1];
-
-  FILE *f = fopen(filename, "w");
-
-  if (!f) {
-    printf("could not open file: errno = %d\n", errno);
-    return EXIT_FAILURE;
-  }
-
-  const rs_item glue_entries[] = {
-      RS_COMMENT("this file was generated by glue.c; do not modify it by hand"),
-      RS_RAW("use std::os::raw::*;\n"),
-
-      // == luaconf.h ==========================================================
-
-      RS_COMMENT("luaconf.h"),
-      RS_STR("LUA_PATH_DEFAULT", LUA_PATH_DEFAULT),
-      RS_STR("LUA_CPATH_DEFAULT", LUA_CPATH_DEFAULT),
-      RS_STR("LUA_DIRSEP", LUA_DIRSEP),
-      RS_INT("LUA_EXTRASPACE", LUA_EXTRASPACE),
-      RS_INT("LUA_IDSIZE", LUA_IDSIZE),
-      RS_INT("LUAL_BUFFERSIZE", LUAL_BUFFERSIZE),
-      RS_TYPE("LUA_NUMBER",
-              sizeof(LUA_NUMBER) > sizeof(float) ? "c_double" : "c_float"),
-      RS_TYPE("LUA_INTEGER", rs_int_type(sizeof(LUA_INTEGER))),
-#if LUA_VERSION_NUM >= 502
-      RS_TYPE("LUA_UNSIGNED", rs_uint_type(sizeof(LUA_UNSIGNED))),
-#else
-      RS_TYPE("LUA_UNSIGNED", rs_uint_type(sizeof(size_t))),
-#endif
-
-      // == lua.h ==============================================================
-
-      RS_COMMENT("lua.h"),
-      RS_INT("LUA_VERSION_NUM", LUA_VERSION_NUM),
-      RS_STR("LUA_VERSION", LUA_VERSION),
-      RS_STR("LUA_RELEASE", LUA_RELEASE),
-      RS_INT("LUA_REGISTRYINDEX", LUA_REGISTRYINDEX),
-#if LUA_VERSION_NUM == 501
-      RS_INT("LUA_ENVIRONINDEX", LUA_ENVIRONINDEX),
-      RS_INT("LUA_GLOBALSINDEX", LUA_GLOBALSINDEX),
-#endif
-
-      // == lauxlib.h ==========================================================
-
-      RS_COMMENT("lauxlib.h"),
-#if LUA_VERSION_NUM == 503
-      RS_INT("LUAL_NUMSIZES", LUAL_NUMSIZES),
-#endif
-
-      // == lualib.h ===========================================================
-
-      RS_COMMENT("lualib.h"),
-      RS_STR("LUA_COLIBNAME", LUA_COLIBNAME),
-      RS_STR("LUA_TABLIBNAME", LUA_TABLIBNAME),
-      RS_STR("LUA_IOLIBNAME", LUA_IOLIBNAME),
-      RS_STR("LUA_OSLIBNAME", LUA_OSLIBNAME),
-      RS_STR("LUA_STRLIBNAME", LUA_STRLIBNAME),
-#ifdef LUA_UTF8LIBNAME
-      RS_STR("LUA_UTF8LIBNAME", LUA_UTF8LIBNAME),
-#endif
-#ifdef LUA_BITLIBNAME
-      RS_STR("LUA_BITLIBNAME", LUA_BITLIBNAME),
-#endif
-      RS_STR("LUA_MATHLIBNAME", LUA_MATHLIBNAME),
-      RS_STR("LUA_DBLIBNAME", LUA_DBLIBNAME),
-      RS_STR("LUA_LOADLIBNAME", LUA_LOADLIBNAME),
-#ifdef LUA_JITLIBNAME
-      RS_STR("LUA_JITLIBNAME", LUA_JITLIBNAME),
-#endif
-#ifdef LUA_FFILIBNAME
-      RS_STR("LUA_FFILIBNAME", LUA_FFILIBNAME),
-#endif
-  };
-
-  if (!write_items(f, glue_entries)) {
-    printf("%s: error generating %s; aborting\n", argv[0], filename);
-    return EXIT_FAILURE;
-  }
-
-  fclose(f);
-
-  return EXIT_SUCCESS;
-}

src/ffi/lauxlib.rs

@@ -1,304 +0,0 @@
-// The MIT License (MIT)
-//
-// Copyright (c) 2019 A. Orlenko
-// Copyright (c) 2014 J.C. Moyer
-//
-// Permission is hereby granted, free of charge, to any person obtaining a copy
-// of this software and associated documentation files (the "Software"), to deal
-// in the Software without restriction, including without limitation the rights
-// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-// copies of the Software, and to permit persons to whom the Software is
-// furnished to do so, subject to the following conditions:
-//
-// The above copyright notice and this permission notice shall be included in
-// all copies or substantial portions of the Software.
-//
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-// THE SOFTWARE.
-
-//! Contains definitions from `lauxlib.h`.
-
-use std::os::raw::{c_char, c_int, c_long, c_void};
-use std::ptr;
-
-use super::lua::{self, lua_CFunction, lua_Integer, lua_Number, lua_State};
-
-#[cfg(feature = "lua53")]
-pub use super::glue::LUAL_NUMSIZES;
-
-#[cfg(any(feature = "lua52", feature = "lua51", feature = "luajit"))]
-pub use super::compat53::{luaL_getmetafield, luaL_newmetatable, luaL_requiref, luaL_tolstring};
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-pub use super::compat53::{
-    luaL_checkstack, luaL_checkversion, luaL_getsubtable, luaL_len, luaL_loadbufferx,
-    luaL_setfuncs, luaL_setmetatable, luaL_testudata, luaL_traceback,
-};
-
-// extra error code for 'luaL_load'
-pub const LUA_ERRFILE: c_int = lua::LUA_ERRERR + 1;
-
-#[repr(C)]
-pub struct luaL_Reg {
-    pub name: *const c_char,
-    pub func: lua_CFunction,
-}
-
-#[cfg(any(feature = "lua53", feature = "lua52"))]
-#[inline(always)]
-pub unsafe fn luaL_checkversion(L: *mut lua_State) {
-    #[cfg(feature = "lua53")]
-    luaL_checkversion_(
-        L,
-        lua::LUA_VERSION_NUM as lua_Number,
-        LUAL_NUMSIZES as usize,
-    );
-    #[cfg(feature = "lua52")]
-    luaL_checkversion_(L, lua::LUA_VERSION_NUM as lua_Number);
-}
-
-extern "C" {
-    #[cfg(feature = "lua53")]
-    pub fn luaL_checkversion_(L: *mut lua_State, ver: lua_Number, sz: usize);
-    #[cfg(feature = "lua52")]
-    pub fn luaL_checkversion_(L: *mut lua_State, ver: lua_Number);
-
-    #[cfg(feature = "lua53")]
-    pub fn luaL_getmetafield(L: *mut lua_State, obj: c_int, e: *const c_char) -> c_int;
-    #[cfg(any(feature = "lua52", feature = "lua51", feature = "luajit"))]
-    #[link_name = "luaL_getmetafield"]
-    pub fn luaL_getmetafield_old(L: *mut lua_State, obj: c_int, e: *const c_char) -> c_int;
-
-    pub fn luaL_callmeta(L: *mut lua_State, obj: c_int, e: *const c_char) -> c_int;
-    #[cfg(feature = "lua53")]
-    pub fn luaL_tolstring(L: *mut lua_State, idx: c_int, len: *mut usize) -> *const c_char;
-    pub fn luaL_argerror(L: *mut lua_State, arg: c_int, l: *const c_char) -> c_int;
-    pub fn luaL_checklstring(L: *mut lua_State, arg: c_int, l: *mut usize) -> *const c_char;
-    pub fn luaL_optlstring(
-        L: *mut lua_State,
-        arg: c_int,
-        def: *const c_char,
-        l: *mut usize,
-    ) -> *const c_char;
-    pub fn luaL_checknumber(L: *mut lua_State, arg: c_int) -> lua_Number;
-    pub fn luaL_optnumber(L: *mut lua_State, arg: c_int, def: lua_Number) -> lua_Number;
-    pub fn luaL_checkinteger(L: *mut lua_State, arg: c_int) -> lua_Integer;
-    pub fn luaL_optinteger(L: *mut lua_State, arg: c_int, def: lua_Integer) -> lua_Integer;
-
-    #[cfg(any(feature = "lua53", feature = "lua52"))]
-    pub fn luaL_checkstack(L: *mut lua_State, sz: c_int, msg: *const c_char);
-    pub fn luaL_checktype(L: *mut lua_State, arg: c_int, t: c_int);
-    pub fn luaL_checkany(L: *mut lua_State, arg: c_int);
-
-    #[cfg(feature = "lua53")]
-    pub fn luaL_newmetatable(L: *mut lua_State, tname: *const c_char) -> c_int;
-    #[cfg(any(feature = "lua52", feature = "lua51", feature = "luajit"))]
-    #[link_name = "luaL_newmetatable"]
-    pub fn luaL_newmetatable_old(L: *mut lua_State, tname: *const c_char) -> c_int;
-
-    #[cfg(any(feature = "lua53", feature = "lua52"))]
-    pub fn luaL_setmetatable(L: *mut lua_State, tname: *const c_char);
-    #[cfg(any(feature = "lua53", feature = "lua52"))]
-    pub fn luaL_testudata(L: *mut lua_State, ud: c_int, tname: *const c_char) -> *mut c_void;
-    pub fn luaL_checkudata(L: *mut lua_State, ud: c_int, tname: *const c_char) -> *mut c_void;
-
-    pub fn luaL_where(L: *mut lua_State, lvl: c_int);
-    pub fn luaL_error(L: *mut lua_State, fmt: *const c_char, ...) -> !;
-
-    // TODO: test this
-    pub fn luaL_checkoption(
-        L: *mut lua_State,
-        arg: c_int,
-        def: *const c_char,
-        lst: *const *const c_char,
-    ) -> c_int;
-
-    #[cfg(any(feature = "lua53", feature = "lua52"))]
-    pub fn luaL_fileresult(L: *mut lua_State, stat: c_int, fname: *const c_char) -> c_int;
-    #[cfg(any(feature = "lua53", feature = "lua52"))]
-    pub fn luaL_execresult(L: *mut lua_State, stat: c_int) -> c_int;
-}
-
-// pre-defined references
-pub const LUA_NOREF: c_int = -2;
-pub const LUA_REFNIL: c_int = -1;
-
-extern "C" {
-    pub fn luaL_ref(L: *mut lua_State, t: c_int) -> c_int;
-    pub fn luaL_unref(L: *mut lua_State, t: c_int, r: c_int);
-
-    #[cfg(any(feature = "lua53", feature = "lua52"))]
-    pub fn luaL_loadfilex(L: *mut lua_State, filename: *const c_char, mode: *const c_char)
-        -> c_int;
-    #[cfg(any(feature = "lua51", feature = "luajit"))]
-    pub fn luaL_loadfile(L: *mut lua_State, filename: *const c_char) -> c_int;
-}
-
-#[cfg(any(feature = "lua53", feature = "lua52"))]
-#[inline(always)]
-pub unsafe fn luaL_loadfile(L: *mut lua_State, f: *const c_char) -> c_int {
-    luaL_loadfilex(L, f, ptr::null())
-}
-
-extern "C" {
-    #[cfg(any(feature = "lua53", feature = "lua52"))]
-    pub fn luaL_loadbufferx(
-        L: *mut lua_State,
-        buff: *const c_char,
-        sz: usize,
-        name: *const c_char,
-        mode: *const c_char,
-    ) -> c_int;
-    #[cfg(any(feature = "lua51", feature = "luajit"))]
-    pub fn luaL_loadbuffer(
-        L: *mut lua_State,
-        buff: *const c_char,
-        sz: usize,
-        name: *const c_char,
-    ) -> c_int;
-    pub fn luaL_loadstring(L: *mut lua_State, s: *const c_char) -> c_int;
-
-    pub fn luaL_newstate() -> *mut lua_State;
-
-    #[cfg(any(feature = "lua53", feature = "lua52"))]
-    pub fn luaL_len(L: *mut lua_State, idx: c_int) -> lua_Integer;
-
-    pub fn luaL_gsub(
-        L: *mut lua_State,
-        s: *const c_char,
-        p: *const c_char,
-        r: *const c_char,
-    ) -> *const c_char;
-
-    #[cfg(any(feature = "lua53", feature = "lua52"))]
-    pub fn luaL_setfuncs(L: *mut lua_State, l: *const luaL_Reg, nup: c_int);
-
-    #[cfg(any(feature = "lua53", feature = "lua52"))]
-    pub fn luaL_getsubtable(L: *mut lua_State, idx: c_int, fname: *const c_char) -> c_int;
-
-    #[cfg(any(feature = "lua53", feature = "lua52"))]
-    pub fn luaL_traceback(L: *mut lua_State, L1: *mut lua_State, msg: *const c_char, level: c_int);
-
-    // Skip Lua 5.2 implementation in favor of the compat53 one
-    #[cfg(feature = "lua53")]
-    pub fn luaL_requiref(
-        L: *mut lua_State,
-        modname: *const c_char,
-        openf: lua_CFunction,
-        glb: c_int,
-    );
-}
-
-#[inline(always)]
-#[allow(unused_variables)]
-pub unsafe fn luaL_newlibtable(L: *mut lua_State, l: *const luaL_Reg) {
-    // TODO: figure out how to pass an appropriate hint for the second param
-    // this involves correcting the second parameter's type; in C this is
-    // sizeof(l)/sizeof(l[0])
-    lua::lua_createtable(L, 0, 0)
-}
-
-#[inline(always)]
-pub unsafe fn luaL_newlib(L: *mut lua_State, l: *const luaL_Reg) {
-    luaL_checkversion(L);
-    luaL_newlibtable(L, l);
-    luaL_setfuncs(L, l, 0)
-}
-
-#[inline(always)]
-pub unsafe fn luaL_argcheck(L: *mut lua_State, cond: c_int, arg: c_int, extramsg: *const c_char) {
-    if cond == 0 {
-        luaL_argerror(L, arg, extramsg);
-    }
-}
-
-#[inline(always)]
-pub unsafe fn luaL_checkstring(L: *mut lua_State, n: c_int) -> *const c_char {
-    luaL_checklstring(L, n, ptr::null_mut())
-}
-
-#[inline(always)]
-pub unsafe fn luaL_optstring(L: *mut lua_State, n: c_int, d: *const c_char) -> *const c_char {
-    luaL_optlstring(L, n, d, ptr::null_mut())
-}
-
-// From 5.3 user manual:
-// Macros to project non-default integer types (luaL_checkint, luaL_optint,
-// luaL_checklong, luaL_optlong) were deprecated. Use their equivalent over
-// lua_Integer with a type cast (or, when possible, use lua_Integer in your
-// code).
-#[inline(always)]
-//#[deprecated]
-pub unsafe fn luaL_checkint(L: *mut lua_State, n: c_int) -> c_int {
-    luaL_checkinteger(L, n) as c_int
-}
-
-#[inline(always)]
-//#[deprecated]
-pub unsafe fn luaL_optint(L: *mut lua_State, n: c_int, d: c_int) -> c_int {
-    luaL_optinteger(L, n, d as lua_Integer) as c_int
-}
-
-#[inline(always)]
-//#[deprecated]
-pub unsafe fn luaL_checklong(L: *mut lua_State, n: c_int) -> c_long {
-    luaL_checkinteger(L, n) as c_long
-}
-
-#[inline(always)]
-//#[deprecated]
-pub unsafe fn luaL_optlong(L: *mut lua_State, n: c_int, d: c_long) -> c_long {
-    luaL_optinteger(L, n, d as lua_Integer) as c_long
-}
-
-#[inline(always)]
-pub unsafe fn luaL_typename(L: *mut lua_State, i: c_int) -> *const c_char {
-    lua::lua_typename(L, lua::lua_type(L, i))
-}
-
-#[inline(always)]
-pub unsafe fn luaL_dofile(L: *mut lua_State, filename: *const c_char) -> c_int {
-    let status = luaL_loadfile(L, filename);
-    if status == 0 {
-        lua::lua_pcall(L, 0, lua::LUA_MULTRET, 0)
-    } else {
-        status
-    }
-}
-
-#[inline(always)]
-pub unsafe fn luaL_dostring(L: *mut lua_State, s: *const c_char) -> c_int {
-    let status = luaL_loadstring(L, s);
-    if status == 0 {
-        lua::lua_pcall(L, 0, lua::LUA_MULTRET, 0)
-    } else {
-        status
-    }
-}
-
-#[inline(always)]
-pub unsafe fn luaL_getmetatable(L: *mut lua_State, n: *const c_char) {
-    lua::lua_getfield(L, lua::LUA_REGISTRYINDEX, n);
-}
-
-// luaL_opt would be implemented here but it is undocumented, so it's omitted
-
-#[cfg(any(feature = "lua53", feature = "lua52"))]
-#[inline(always)]
-pub unsafe fn luaL_loadbuffer(
-    L: *mut lua_State,
-    s: *const c_char,
-    sz: usize,
-    n: *const c_char,
-) -> c_int {
-    luaL_loadbufferx(L, s, sz, n, ptr::null())
-}
-
-// TODO: Add buffer API
-
-// omitted: old module system compatibility

src/ffi/lua.rs

@@ -1,706 +0,0 @@
-// The MIT License (MIT)
-//
-// Copyright (c) 2019 A. Orlenko
-// Copyright (c) 2014 J.C. Moyer
-//
-// Permission is hereby granted, free of charge, to any person obtaining a copy
-// of this software and associated documentation files (the "Software"), to deal
-// in the Software without restriction, including without limitation the rights
-// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-// copies of the Software, and to permit persons to whom the Software is
-// furnished to do so, subject to the following conditions:
-//
-// The above copyright notice and this permission notice shall be included in
-// all copies or substantial portions of the Software.
-//
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-// THE SOFTWARE.
-
-//! Contains definitions from `lua.h`.
-
-#[cfg(any(feature = "lua53", feature = "lua52"))]
-use std::os::raw::c_uchar;
-use std::os::raw::{c_char, c_int, c_void};
-use std::ptr;
-
-use super::luaconf;
-
-pub use super::glue::{LUA_RELEASE, LUA_VERSION, LUA_VERSION_NUM};
-
-pub use super::glue::LUA_REGISTRYINDEX;
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-pub use super::glue::{LUA_ENVIRONINDEX, LUA_GLOBALSINDEX};
-
-pub const LUA_SIGNATURE: &'static [u8] = b"\x1bLua";
-
-// option for multiple returns in 'lua_pcall' and 'lua_call'
-pub const LUA_MULTRET: c_int = -1;
-
-#[cfg(any(feature = "lua52", feature = "lua51", feature = "luajit"))]
-pub use super::compat53::{
-    lua_dump, lua_getextraspace, lua_getfield, lua_geti, lua_gettable, lua_getuservalue,
-    lua_isinteger, lua_pushlstring, lua_rawget, lua_rawgeti, lua_rawgetp, lua_rotate, lua_seti,
-    lua_stringtonumber, lua_tointegerx,
-};
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-pub use super::compat53::{
-    lua_absindex, lua_arith, lua_compare, lua_copy, lua_len, lua_pushglobaltable, lua_pushstring,
-    lua_rawlen, lua_rawsetp, lua_resume, lua_setuservalue, lua_tonumberx, lua_upvalueindex,
-};
-
-#[cfg(feature = "lua52")]
-pub use super::compat53::lua_getglobal;
-
-#[cfg(any(feature = "lua53", feature = "lua52"))]
-#[inline(always)]
-pub fn lua_upvalueindex(i: c_int) -> c_int {
-    LUA_REGISTRYINDEX - i
-}
-
-// thread status
-pub const LUA_OK: c_int = 0;
-pub const LUA_YIELD: c_int = 1;
-pub const LUA_ERRRUN: c_int = 2;
-pub const LUA_ERRSYNTAX: c_int = 3;
-pub const LUA_ERRMEM: c_int = 4;
-#[cfg(any(feature = "lua53", feature = "lua52"))]
-pub const LUA_ERRGCMM: c_int = 5;
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-pub const LUA_ERRERR: c_int = 5;
-#[cfg(any(feature = "lua53", feature = "lua52"))]
-pub const LUA_ERRERR: c_int = 6;
-
-pub type lua_State = c_void;
-
-// basic types
-pub const LUA_TNONE: c_int = -1;
-
-pub const LUA_TNIL: c_int = 0;
-pub const LUA_TBOOLEAN: c_int = 1;
-pub const LUA_TLIGHTUSERDATA: c_int = 2;
-pub const LUA_TNUMBER: c_int = 3;
-pub const LUA_TSTRING: c_int = 4;
-pub const LUA_TTABLE: c_int = 5;
-pub const LUA_TFUNCTION: c_int = 6;
-pub const LUA_TUSERDATA: c_int = 7;
-pub const LUA_TTHREAD: c_int = 8;
-
-#[cfg(any(feature = "lua53", feature = "lua52"))]
-pub const LUA_NUMTAGS: c_int = 9;
-
-// minimum stack available to a C function
-pub const LUA_MINSTACK: c_int = 20;
-
-// predefined values in the registry
-#[cfg(any(feature = "lua53", feature = "lua52"))]
-pub const LUA_RIDX_MAINTHREAD: lua_Integer = 1;
-#[cfg(any(feature = "lua53", feature = "lua52"))]
-pub const LUA_RIDX_GLOBALS: lua_Integer = 2;
-#[cfg(any(feature = "lua53", feature = "lua52"))]
-pub const LUA_RIDX_LAST: lua_Integer = LUA_RIDX_GLOBALS;
-
-/// A Lua number, usually equivalent to `f64`.
-pub type lua_Number = luaconf::LUA_NUMBER;
-
-/// A Lua integer, usually equivalent to `i64`.
-pub type lua_Integer = luaconf::LUA_INTEGER;
-
-// unsigned integer type
-pub type lua_Unsigned = luaconf::LUA_UNSIGNED;
-
-// type for continuation-function contexts
-#[cfg(feature = "lua53")]
-pub type lua_KContext = luaconf::LUA_KCONTEXT;
-
-/// Type for native functions that can be passed to Lua.
-pub type lua_CFunction = unsafe extern "C" fn(L: *mut lua_State) -> c_int;
-
-// Type for continuation functions
-#[cfg(feature = "lua53")]
-pub type lua_KFunction =
-    unsafe extern "C" fn(L: *mut lua_State, status: c_int, ctx: lua_KContext) -> c_int;
-
-// Type for functions that read/write blocks when loading/dumping Lua chunks
-pub type lua_Reader =
-    unsafe extern "C" fn(L: *mut lua_State, ud: *mut c_void, sz: *mut usize) -> *const c_char;
-pub type lua_Writer =
-    unsafe extern "C" fn(L: *mut lua_State, p: *const c_void, sz: usize, ud: *mut c_void) -> c_int;
-
-/// Type for memory-allocation functions.
-pub type lua_Alloc = unsafe extern "C" fn(
-    ud: *mut c_void,
-    ptr: *mut c_void,
-    osize: usize,
-    nsize: usize,
-) -> *mut c_void;
-
-extern "C" {
-    // state manipulation
-    pub fn lua_newstate(f: lua_Alloc, ud: *mut c_void) -> *mut lua_State;
-    pub fn lua_close(L: *mut lua_State);
-    pub fn lua_newthread(L: *mut lua_State) -> *mut lua_State;
-
-    pub fn lua_atpanic(L: *mut lua_State, panicf: lua_CFunction) -> lua_CFunction;
-
-    #[cfg(feature = "lua53")]
-    pub fn lua_version(L: *mut lua_State) -> *const lua_Number;
-
-    // basic stack manipulation
-    #[cfg(any(feature = "lua53", feature = "lua52"))]
-    pub fn lua_absindex(L: *mut lua_State, idx: c_int) -> c_int;
-    pub fn lua_gettop(L: *mut lua_State) -> c_int;
-    pub fn lua_settop(L: *mut lua_State, idx: c_int);
-    pub fn lua_pushvalue(L: *mut lua_State, idx: c_int);
-    #[cfg(any(feature = "lua52", feature = "lua51", feature = "luajit"))]
-    pub fn lua_remove(L: *mut lua_State, idx: c_int);
-    #[cfg(any(feature = "lua52", feature = "lua51", feature = "luajit"))]
-    pub fn lua_insert(L: *mut lua_State, idx: c_int);
-    #[cfg(any(feature = "lua52", feature = "lua51", feature = "luajit"))]
-    pub fn lua_replace(L: *mut lua_State, idx: c_int);
-    #[cfg(feature = "lua53")]
-    pub fn lua_rotate(L: *mut lua_State, idx: c_int, n: c_int);
-    #[cfg(any(feature = "lua53", feature = "lua52"))]
-    pub fn lua_copy(L: *mut lua_State, fromidx: c_int, toidx: c_int);
-    pub fn lua_checkstack(L: *mut lua_State, sz: c_int) -> c_int;
-
-    pub fn lua_xmove(from: *mut lua_State, to: *mut lua_State, n: c_int);
-
-    // access functions (stack -> C)
-    pub fn lua_isnumber(L: *mut lua_State, idx: c_int) -> c_int;
-    pub fn lua_isstring(L: *mut lua_State, idx: c_int) -> c_int;
-    pub fn lua_iscfunction(L: *mut lua_State, idx: c_int) -> c_int;
-    #[cfg(feature = "lua53")]
-    pub fn lua_isinteger(L: *mut lua_State, idx: c_int) -> c_int;
-    pub fn lua_isuserdata(L: *mut lua_State, idx: c_int) -> c_int;
-    pub fn lua_type(L: *mut lua_State, idx: c_int) -> c_int;
-    pub fn lua_typename(L: *mut lua_State, tp: c_int) -> *const c_char;
-
-    #[cfg(any(feature = "lua51", feature = "luajit"))]
-    pub fn lua_tonumber(L: *mut lua_State, idx: c_int) -> lua_Number;
-    #[cfg(any(feature = "lua53", feature = "lua52"))]
-    pub fn lua_tonumberx(L: *mut lua_State, idx: c_int, isnum: *mut c_int) -> lua_Number;
-    #[cfg(any(feature = "lua51", feature = "luajit"))]
-    pub fn lua_tointeger(L: *mut lua_State, idx: c_int) -> lua_Integer;
-    #[cfg(feature = "lua53")]
-    pub fn lua_tointegerx(L: *mut lua_State, idx: c_int, isnum: *mut c_int) -> lua_Integer;
-    pub fn lua_toboolean(L: *mut lua_State, idx: c_int) -> c_int;
-    pub fn lua_tolstring(L: *mut lua_State, idx: c_int, len: *mut usize) -> *const c_char;
-    #[cfg(any(feature = "lua51", feature = "luajit"))]
-    pub fn lua_objlen(L: *mut lua_State, idx: c_int) -> usize;
-    #[cfg(any(feature = "lua53", feature = "lua52"))]
-    pub fn lua_rawlen(L: *mut lua_State, idx: c_int) -> usize;
-    pub fn lua_tocfunction(L: *mut lua_State, idx: c_int) -> lua_CFunction;
-    pub fn lua_touserdata(L: *mut lua_State, idx: c_int) -> *mut c_void;
-    pub fn lua_tothread(L: *mut lua_State, idx: c_int) -> *mut lua_State;
-    pub fn lua_topointer(L: *mut lua_State, idx: c_int) -> *const c_void;
-}
-
-// Comparison and arithmetic functions
-pub const LUA_OPADD: c_int = 0;
-pub const LUA_OPSUB: c_int = 1;
-pub const LUA_OPMUL: c_int = 2;
-
-#[cfg(any(feature = "lua52", feature = "lua51", feature = "luajit"))]
-pub const LUA_OPDIV: c_int = 3;
-#[cfg(any(feature = "lua52", feature = "lua51", feature = "luajit"))]
-pub const LUA_OPMOD: c_int = 4;
-#[cfg(any(feature = "lua52", feature = "lua51", feature = "luajit"))]
-pub const LUA_OPPOW: c_int = 5;
-#[cfg(any(feature = "lua52", feature = "lua51", feature = "luajit"))]
-pub const LUA_OPUNM: c_int = 6;
-
-#[cfg(feature = "lua53")]
-pub const LUA_OPMOD: c_int = 3;
-#[cfg(feature = "lua53")]
-pub const LUA_OPPOW: c_int = 4;
-#[cfg(feature = "lua53")]
-pub const LUA_OPDIV: c_int = 5;
-#[cfg(feature = "lua53")]
-pub const LUA_OPIDIV: c_int = 6;
-#[cfg(feature = "lua53")]
-pub const LUA_OPBAND: c_int = 7;
-#[cfg(feature = "lua53")]
-pub const LUA_OPBOR: c_int = 8;
-#[cfg(feature = "lua53")]
-pub const LUA_OPBXOR: c_int = 9;
-#[cfg(feature = "lua53")]
-pub const LUA_OPSHL: c_int = 10;
-#[cfg(feature = "lua53")]
-pub const LUA_OPSHR: c_int = 11;
-#[cfg(feature = "lua53")]
-pub const LUA_OPUNM: c_int = 12;
-#[cfg(feature = "lua53")]
-pub const LUA_OPBNOT: c_int = 13;
-
-extern "C" {
-    #[cfg(any(feature = "lua53", feature = "lua52"))]
-    pub fn lua_arith(L: *mut lua_State, op: c_int);
-}
-
-pub const LUA_OPEQ: c_int = 0;
-pub const LUA_OPLT: c_int = 1;
-pub const LUA_OPLE: c_int = 2;
-
-extern "C" {
-    #[cfg(any(feature = "lua51", feature = "luajit"))]
-    pub fn lua_equal(L: *mut lua_State, idx1: c_int, idx2: c_int) -> c_int;
-    pub fn lua_rawequal(L: *mut lua_State, idx1: c_int, idx2: c_int) -> c_int;
-    #[cfg(any(feature = "lua51", feature = "luajit"))]
-    pub fn lua_lessthan(L: *mut lua_State, idx1: c_int, idx2: c_int) -> c_int;
-    #[cfg(any(feature = "lua53", feature = "lua52"))]
-    pub fn lua_compare(L: *mut lua_State, idx1: c_int, idx2: c_int, op: c_int) -> c_int;
-}
-
-// push functions (C -> stack)
-extern "C" {
-    pub fn lua_pushnil(L: *mut lua_State);
-    pub fn lua_pushnumber(L: *mut lua_State, n: lua_Number);
-    pub fn lua_pushinteger(L: *mut lua_State, n: lua_Integer);
-
-    #[cfg(feature = "lua53")]
-    pub fn lua_pushlstring(L: *mut lua_State, s: *const c_char, l: usize) -> *const c_char;
-    #[cfg(any(feature = "lua52", feature = "lua51", feature = "luajit"))]
-    #[link_name = "lua_pushlstring"]
-    pub fn lua_pushlstring_old(L: *mut lua_State, s: *const c_char, l: usize) -> *const c_char;
-
-    #[cfg(any(feature = "lua53", feature = "lua52"))]
-    pub fn lua_pushstring(L: *mut lua_State, s: *const c_char) -> *const c_char;
-    #[cfg(any(feature = "lua51", feature = "luajit"))]
-    #[link_name = "lua_pushstring"]
-    pub fn lua_pushstring_old(L: *mut lua_State, s: *const c_char) -> *const c_char;
-
-    // TODO: omitted:
-    // lua_pushvfstring
-    pub fn lua_pushfstring(L: *mut lua_State, fmt: *const c_char, ...) -> *const c_char;
-    pub fn lua_pushcclosure(L: *mut lua_State, f: lua_CFunction, n: c_int);
-    pub fn lua_pushboolean(L: *mut lua_State, b: c_int);
-    pub fn lua_pushlightuserdata(L: *mut lua_State, p: *mut c_void);
-    pub fn lua_pushthread(L: *mut lua_State) -> c_int;
-}
-
-// get functions (Lua -> stack)
-extern "C" {
-    #[cfg(feature = "lua53")]
-    pub fn lua_getglobal(L: *mut lua_State, var: *const c_char) -> c_int;
-    #[cfg(feature = "lua52")]
-    #[link_name = "lua_getglobal"]
-    pub fn lua_getglobal_old(L: *mut lua_State, var: *const c_char);
-
-    #[cfg(feature = "lua53")]
-    pub fn lua_gettable(L: *mut lua_State, idx: c_int) -> c_int;
-    #[cfg(any(feature = "lua52", feature = "lua51", feature = "luajit"))]
-    #[link_name = "lua_gettable"]
-    pub fn lua_gettable_old(L: *mut lua_State, idx: c_int);
-
-    #[cfg(feature = "lua53")]
-    pub fn lua_getfield(L: *mut lua_State, idx: c_int, k: *const c_char) -> c_int;
-    #[cfg(any(feature = "lua52", feature = "lua51", feature = "luajit"))]
-    #[link_name = "lua_getfield"]
-    pub fn lua_getfield_old(L: *mut lua_State, idx: c_int, k: *const c_char);
-
-    #[cfg(feature = "lua53")]
-    pub fn lua_geti(L: *mut lua_State, idx: c_int, n: lua_Integer) -> c_int;
-
-    #[cfg(feature = "lua53")]
-    pub fn lua_rawget(L: *mut lua_State, idx: c_int) -> c_int;
-    #[cfg(any(feature = "lua52", feature = "lua51", feature = "luajit"))]
-    #[link_name = "lua_rawget"]
-    pub fn lua_rawget_old(L: *mut lua_State, idx: c_int);
-
-    #[cfg(feature = "lua53")]
-    pub fn lua_rawgeti(L: *mut lua_State, idx: c_int, n: lua_Integer) -> c_int;
-    #[cfg(any(feature = "lua52", feature = "lua51", feature = "luajit"))]
-    #[link_name = "lua_rawgeti"]
-    pub fn lua_rawgeti_old(L: *mut lua_State, idx: c_int, n: lua_Integer);
-
-    #[cfg(feature = "lua53")]
-    pub fn lua_rawgetp(L: *mut lua_State, idx: c_int, p: *const c_void) -> c_int;
-    #[cfg(feature = "lua52")]
-    #[link_name = "lua_rawgetp"]
-    pub fn lua_rawgetp_old(L: *mut lua_State, idx: c_int, p: *const c_void);
-
-    pub fn lua_createtable(L: *mut lua_State, narr: c_int, nrec: c_int);
-    pub fn lua_newuserdata(L: *mut lua_State, sz: usize) -> *mut c_void;
-    pub fn lua_getmetatable(L: *mut lua_State, objindex: c_int) -> c_int;
-
-    #[cfg(feature = "lua53")]
-    pub fn lua_getuservalue(L: *mut lua_State, idx: c_int) -> c_int;
-    #[cfg(feature = "lua52")]
-    #[link_name = "lua_getuservalue"]
-    pub fn lua_getuservalue_old(L: *mut lua_State, idx: c_int);
-    #[cfg(any(feature = "lua51", feature = "luajit"))]
-    pub fn lua_getfenv(L: *mut lua_State, idx: c_int);
-}
-
-// set functions (stack -> Lua)
-extern "C" {
-    #[cfg(any(feature = "lua53", feature = "lua52"))]
-    pub fn lua_setglobal(L: *mut lua_State, var: *const c_char);
-    pub fn lua_settable(L: *mut lua_State, idx: c_int);
-    pub fn lua_setfield(L: *mut lua_State, idx: c_int, k: *const c_char);
-    #[cfg(feature = "lua53")]
-    pub fn lua_seti(L: *mut lua_State, idx: c_int, n: lua_Integer);
-    pub fn lua_rawset(L: *mut lua_State, idx: c_int);
-    pub fn lua_rawseti(L: *mut lua_State, idx: c_int, n: lua_Integer);
-    #[cfg(any(feature = "lua53", feature = "lua52"))]
-    pub fn lua_rawsetp(L: *mut lua_State, idx: c_int, p: *const c_void);
-    pub fn lua_setmetatable(L: *mut lua_State, objindex: c_int) -> c_int;
-    #[cfg(any(feature = "lua53", feature = "lua52"))]
-    pub fn lua_setuservalue(L: *mut lua_State, idx: c_int);
-    #[cfg(any(feature = "lua51", feature = "luajit"))]
-    pub fn lua_setfenv(L: *mut lua_State, idx: c_int) -> c_int;
-}
-
-// 'load' and 'call' functions (load and run Lua code)
-extern "C" {
-    #[cfg(feature = "lua53")]
-    pub fn lua_callk(
-        L: *mut lua_State,
-        nargs: c_int,
-        nresults: c_int,
-        ctx: lua_KContext,
-        k: Option<lua_KFunction>,
-    );
-    #[cfg(feature = "lua52")]
-    pub fn lua_callk(
-        L: *mut lua_State,
-        nargs: c_int,
-        nresults: c_int,
-        ctx: c_int,
-        k: Option<lua_CFunction>,
-    );
-
-    #[cfg(feature = "lua53")]
-    pub fn lua_pcallk(
-        L: *mut lua_State,
-        nargs: c_int,
-        nresults: c_int,
-        errfunc: c_int,
-        ctx: lua_KContext,
-        k: Option<lua_KFunction>,
-    ) -> c_int;
-    #[cfg(feature = "lua52")]
-    pub fn lua_pcallk(
-        L: *mut lua_State,
-        nargs: c_int,
-        nresults: c_int,
-        errfunc: c_int,
-        ctx: c_int,
-        k: Option<lua_CFunction>,
-    ) -> c_int;
-
-    #[cfg(feature = "lua52")]
-    pub fn lua_getctx(L: *mut lua_State, ctx: *mut c_int) -> c_int;
-
-    #[cfg(any(feature = "lua51", feature = "luajit"))]
-    pub fn lua_call(L: *mut lua_State, nargs: c_int, nresults: c_int);
-    #[cfg(any(feature = "lua51", feature = "luajit"))]
-    pub fn lua_pcall(L: *mut lua_State, nargs: c_int, nresults: c_int, errfunc: c_int) -> c_int;
-
-    // TODO
-    pub fn lua_load(
-        L: *mut lua_State,
-        reader: lua_Reader,
-        dt: *mut c_void,
-        chunkname: *const c_char,
-        mode: *const c_char,
-    ) -> c_int;
-
-    #[cfg(feature = "lua53")]
-    pub fn lua_dump(
-        L: *mut lua_State,
-        writer: lua_Writer,
-        data: *mut c_void,
-        strip: c_int,
-    ) -> c_int;
-    #[cfg(any(feature = "lua52", feature = "lua51", feature = "luajit"))]
-    #[link_name = "lua_dump"]
-    pub fn lua_dump_old(L: *mut lua_State, writer: lua_Writer, data: *mut c_void) -> c_int;
-}
-
-#[cfg(any(feature = "lua53", feature = "lua52"))]
-#[inline(always)]
-pub unsafe fn lua_call(L: *mut lua_State, n: c_int, r: c_int) {
-    lua_callk(L, n, r, 0, None)
-}
-
-#[cfg(any(feature = "lua53", feature = "lua52"))]
-#[inline(always)]
-pub unsafe fn lua_pcall(L: *mut lua_State, n: c_int, r: c_int, f: c_int) -> c_int {
-    lua_pcallk(L, n, r, f, 0, None)
-}
-
-// coroutine functions
-extern "C" {
-    #[cfg(feature = "lua53")]
-    pub fn lua_yieldk(
-        L: *mut lua_State,
-        nresults: c_int,
-        ctx: lua_KContext,
-        k: Option<lua_KFunction>,
-    ) -> c_int;
-    #[cfg(feature = "lua52")]
-    pub fn lua_yieldk(
-        L: *mut lua_State,
-        nresults: c_int,
-        ctx: c_int,
-        k: Option<lua_CFunction>,
-    ) -> c_int;
-    #[cfg(any(feature = "lua51", feature = "luajit"))]
-    pub fn lua_yield(L: *mut lua_State, nresults: c_int) -> c_int;
-
-    #[cfg(any(feature = "lua53", feature = "lua52"))]
-    pub fn lua_resume(L: *mut lua_State, from: *mut lua_State, narg: c_int) -> c_int;
-    #[cfg(any(feature = "lua51", feature = "luajit"))]
-    #[link_name = "lua_resume"]
-    pub fn lua_resume_old(L: *mut lua_State, narg: c_int) -> c_int;
-
-    pub fn lua_status(L: *mut lua_State) -> c_int;
-    #[cfg(feature = "lua53")]
-    pub fn lua_isyieldable(L: *mut lua_State) -> c_int;
-}
-
-#[cfg(any(feature = "lua53", feature = "lua52"))]
-#[inline(always)]
-pub unsafe fn lua_yield(L: *mut lua_State, n: c_int) -> c_int {
-    lua_yieldk(L, n, 0, None)
-}
-
-// garbage-collection function and options
-pub const LUA_GCSTOP: c_int = 0;
-pub const LUA_GCRESTART: c_int = 1;
-pub const LUA_GCCOLLECT: c_int = 2;
-pub const LUA_GCCOUNT: c_int = 3;
-pub const LUA_GCCOUNTB: c_int = 4;
-pub const LUA_GCSTEP: c_int = 5;
-pub const LUA_GCSETPAUSE: c_int = 6;
-pub const LUA_GCSETSTEPMUL: c_int = 7;
-#[cfg(any(feature = "lua53", feature = "lua52"))]
-pub const LUA_GCISRUNNING: c_int = 9;
-
-extern "C" {
-    pub fn lua_gc(L: *mut lua_State, what: c_int, data: c_int) -> c_int;
-}
-
-// miscellaneous functions
-extern "C" {
-    pub fn lua_error(L: *mut lua_State) -> !;
-    pub fn lua_next(L: *mut lua_State, idx: c_int) -> c_int;
-    pub fn lua_concat(L: *mut lua_State, n: c_int);
-    #[cfg(any(feature = "lua53", feature = "lua52"))]
-    pub fn lua_len(L: *mut lua_State, idx: c_int);
-    #[cfg(feature = "lua53")]
-    pub fn lua_stringtonumber(L: *mut lua_State, s: *const c_char) -> usize;
-    pub fn lua_getallocf(L: *mut lua_State, ud: *mut *mut c_void) -> lua_Alloc;
-    pub fn lua_setallocf(L: *mut lua_State, f: lua_Alloc, ud: *mut c_void);
-}
-
-// some useful macros
-// here, implemented as Rust functions
-#[cfg(feature = "lua53")]
-#[inline(always)]
-pub unsafe fn lua_getextraspace(L: *mut lua_State) -> *mut c_void {
-    L.offset(-super::glue::LUA_EXTRASPACE as isize) as *mut c_void
-}
-
-#[cfg(any(feature = "lua53", feature = "lua52"))]
-#[inline(always)]
-pub unsafe fn lua_tonumber(L: *mut lua_State, i: c_int) -> lua_Number {
-    lua_tonumberx(L, i, ptr::null_mut())
-}
-
-#[cfg(any(feature = "lua53", feature = "lua52"))]
-#[inline(always)]
-pub unsafe fn lua_tointeger(L: *mut lua_State, i: c_int) -> lua_Integer {
-    lua_tointegerx(L, i, ptr::null_mut())
-}
-
-#[inline(always)]
-pub unsafe fn lua_pop(L: *mut lua_State, n: c_int) {
-    lua_settop(L, -n - 1)
-}
-
-#[inline(always)]
-pub unsafe fn lua_newtable(L: *mut lua_State) {
-    lua_createtable(L, 0, 0)
-}
-
-#[inline(always)]
-pub unsafe fn lua_register(L: *mut lua_State, n: *const c_char, f: lua_CFunction) {
-    lua_pushcfunction(L, f);
-    lua_setglobal(L, n)
-}
-
-#[inline(always)]
-pub unsafe fn lua_pushcfunction(L: *mut lua_State, f: lua_CFunction) {
-    lua_pushcclosure(L, f, 0)
-}
-
-#[inline(always)]
-pub unsafe fn lua_isfunction(L: *mut lua_State, n: c_int) -> c_int {
-    (lua_type(L, n) == LUA_TFUNCTION) as c_int
-}
-
-#[inline(always)]
-pub unsafe fn lua_istable(L: *mut lua_State, n: c_int) -> c_int {
-    (lua_type(L, n) == LUA_TTABLE) as c_int
-}
-
-#[inline(always)]
-pub unsafe fn lua_islightuserdata(L: *mut lua_State, n: c_int) -> c_int {
-    (lua_type(L, n) == LUA_TLIGHTUSERDATA) as c_int
-}
-
-#[inline(always)]
-pub unsafe fn lua_isnil(L: *mut lua_State, n: c_int) -> c_int {
-    (lua_type(L, n) == LUA_TNIL) as c_int
-}
-
-#[inline(always)]
-pub unsafe fn lua_isboolean(L: *mut lua_State, n: c_int) -> c_int {
-    (lua_type(L, n) == LUA_TBOOLEAN) as c_int
-}
-
-#[inline(always)]
-pub unsafe fn lua_isthread(L: *mut lua_State, n: c_int) -> c_int {
-    (lua_type(L, n) == LUA_TTHREAD) as c_int
-}
-
-#[inline(always)]
-pub unsafe fn lua_isnone(L: *mut lua_State, n: c_int) -> c_int {
-    (lua_type(L, n) == LUA_TNONE) as c_int
-}
-
-#[inline(always)]
-pub unsafe fn lua_isnoneornil(L: *mut lua_State, n: c_int) -> c_int {
-    (lua_type(L, n) <= 0) as c_int
-}
-
-#[inline(always)]
-pub unsafe fn lua_pushliteral(L: *mut lua_State, s: &'static str) -> *const c_char {
-    use std::ffi::CString;
-    let c_str = CString::new(s).unwrap();
-    lua_pushlstring(L, c_str.as_ptr(), c_str.as_bytes().len())
-}
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-#[inline(always)]
-pub unsafe fn lua_setglobal(L: *mut lua_State, var: *const c_char) {
-    lua_setfield(L, LUA_GLOBALSINDEX, var)
-}
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-#[inline(always)]
-pub unsafe fn lua_getglobal(L: *mut lua_State, var: *const c_char) -> c_int {
-    lua_getfield(L, LUA_GLOBALSINDEX, var)
-}
-
-#[cfg(any(feature = "lua53", feature = "lua52"))]
-#[inline(always)]
-pub unsafe fn lua_pushglobaltable(L: *mut lua_State) -> c_int {
-    lua_rawgeti(L, LUA_REGISTRYINDEX, LUA_RIDX_GLOBALS)
-}
-
-#[inline(always)]
-pub unsafe fn lua_tostring(L: *mut lua_State, i: c_int) -> *const c_char {
-    lua_tolstring(L, i, ptr::null_mut())
-}
-
-#[cfg(feature = "lua53")]
-#[inline(always)]
-pub unsafe fn lua_insert(L: *mut lua_State, idx: c_int) {
-    lua_rotate(L, idx, 1)
-}
-
-#[cfg(feature = "lua53")]
-#[inline(always)]
-pub unsafe fn lua_remove(L: *mut lua_State, idx: c_int) {
-    lua_rotate(L, idx, -1);
-    lua_pop(L, 1)
-}
-
-#[cfg(feature = "lua53")]
-#[inline(always)]
-pub unsafe fn lua_replace(L: *mut lua_State, idx: c_int) {
-    lua_copy(L, -1, idx);
-    lua_pop(L, 1)
-}
-
-// Debug API
-// Event codes
-pub const LUA_HOOKCALL: c_int = 0;
-pub const LUA_HOOKRET: c_int = 1;
-pub const LUA_HOOKLINE: c_int = 2;
-pub const LUA_HOOKCOUNT: c_int = 3;
-pub const LUA_HOOKTAILCALL: c_int = 4;
-
-// Event masks
-pub const LUA_MASKCALL: c_int = 1 << (LUA_HOOKCALL as usize);
-pub const LUA_MASKRET: c_int = 1 << (LUA_HOOKRET as usize);
-pub const LUA_MASKLINE: c_int = 1 << (LUA_HOOKLINE as usize);
-pub const LUA_MASKCOUNT: c_int = 1 << (LUA_HOOKCOUNT as usize);
-
-/// Type for functions to be called on debug events.
-pub type lua_Hook = extern "C" fn(L: *mut lua_State, ar: *mut lua_Debug);
-
-extern "C" {
-    pub fn lua_getstack(L: *mut lua_State, level: c_int, ar: *mut lua_Debug) -> c_int;
-    pub fn lua_getinfo(L: *mut lua_State, what: *const c_char, ar: *mut lua_Debug) -> c_int;
-    pub fn lua_getlocal(L: *mut lua_State, ar: *const lua_Debug, n: c_int) -> *const c_char;
-    pub fn lua_setlocal(L: *mut lua_State, ar: *const lua_Debug, n: c_int) -> *const c_char;
-    pub fn lua_getupvalue(L: *mut lua_State, funcindex: c_int, n: c_int) -> *const c_char;
-    pub fn lua_setupvalue(L: *mut lua_State, funcindex: c_int, n: c_int) -> *const c_char;
-
-    #[cfg(any(feature = "lua53", feature = "lua52"))]
-    pub fn lua_upvalueid(L: *mut lua_State, fidx: c_int, n: c_int) -> *mut c_void;
-    #[cfg(any(feature = "lua53", feature = "lua52"))]
-    pub fn lua_upvaluejoin(L: *mut lua_State, fidx1: c_int, n1: c_int, fidx2: c_int, n2: c_int);
-
-    pub fn lua_sethook(L: *mut lua_State, func: lua_Hook, mask: c_int, count: c_int);
-    pub fn lua_gethook(L: *mut lua_State) -> Option<lua_Hook>;
-    pub fn lua_gethookmask(L: *mut lua_State) -> c_int;
-    pub fn lua_gethookcount(L: *mut lua_State) -> c_int;
-}
-
-#[cfg(any(feature = "lua53", feature = "lua52"))]
-#[repr(C)]
-pub struct lua_Debug {
-    pub event: c_int,
-    pub name: *const c_char,
-    pub namewhat: *const c_char,
-    pub what: *const c_char,
-    pub source: *const c_char,
-    pub currentline: c_int,
-    pub linedefined: c_int,
-    pub lastlinedefined: c_int,
-    pub nups: c_uchar,
-    pub nparams: c_uchar,
-    pub isvararg: c_char,
-    pub istailcall: c_char,
-    pub short_src: [c_char; luaconf::LUA_IDSIZE as usize],
-    // lua.h mentions this is for private use
-    i_ci: *mut c_void,
-}
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-#[repr(C)]
-pub struct lua_Debug {
-    pub event: c_int,
-    pub name: *const c_char,
-    pub namewhat: *const c_char,
-    pub what: *const c_char,
-    pub source: *const c_char,
-    pub currentline: c_int,
-    pub nups: c_int,
-    pub linedefined: c_int,
-    pub lastlinedefined: c_int,
-    pub short_src: [c_char; luaconf::LUA_IDSIZE as usize],
-    // lua.h mentions this is for private use
-    i_ci: c_int,
-}

src/ffi/luaconf.rs

@@ -1,37 +0,0 @@
-// The MIT License (MIT)
-//
-// Copyright (c) 2019 A. Orlenko
-// Copyright (c) 2014 J.C. Moyer
-//
-// Permission is hereby granted, free of charge, to any person obtaining a copy
-// of this software and associated documentation files (the "Software"), to deal
-// in the Software without restriction, including without limitation the rights
-// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-// copies of the Software, and to permit persons to whom the Software is
-// furnished to do so, subject to the following conditions:
-//
-// The above copyright notice and this permission notice shall be included in
-// all copies or substantial portions of the Software.
-//
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-// THE SOFTWARE.
-
-//! Contains definitions from `luaconf.h`.
-
-pub use super::glue::LUAL_BUFFERSIZE;
-pub use super::glue::LUA_INTEGER;
-pub use super::glue::LUA_NUMBER;
-pub use super::glue::LUA_UNSIGNED;
-
-pub use super::glue::LUA_IDSIZE;
-
-#[cfg(feature = "lua53")]
-pub use super::glue::LUAL_NUMSIZES;
-
-#[cfg(feature = "lua53")]
-pub type LUA_KCONTEXT = isize; // intptr_t

src/ffi/lualib.rs

@@ -1,67 +0,0 @@
-// The MIT License (MIT)
-//
-// Copyright (c) 2019 A. Orlenko
-// Copyright (c) 2014 J.C. Moyer
-//
-// Permission is hereby granted, free of charge, to any person obtaining a copy
-// of this software and associated documentation files (the "Software"), to deal
-// in the Software without restriction, including without limitation the rights
-// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-// copies of the Software, and to permit persons to whom the Software is
-// furnished to do so, subject to the following conditions:
-//
-// The above copyright notice and this permission notice shall be included in
-// all copies or substantial portions of the Software.
-//
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-// THE SOFTWARE.
-
-//! Contains definitions from `lualib.h`.
-
-use std::os::raw::c_int;
-
-use super::lua::lua_State;
-
-pub use super::glue::{
-    LUA_COLIBNAME, LUA_DBLIBNAME, LUA_IOLIBNAME, LUA_LOADLIBNAME, LUA_MATHLIBNAME, LUA_OSLIBNAME,
-    LUA_STRLIBNAME, LUA_TABLIBNAME,
-};
-
-#[cfg(feature = "lua53")]
-pub use super::glue::LUA_UTF8LIBNAME;
-
-#[cfg(any(feature = "lua52", feature = "luajit"))]
-pub use super::glue::LUA_BITLIBNAME;
-
-#[cfg(feature = "luajit")]
-pub use super::glue::{LUA_FFILIBNAME, LUA_JITLIBNAME};
-
-extern "C" {
-    pub fn luaopen_base(L: *mut lua_State) -> c_int;
-    #[cfg(any(feature = "lua53", feature = "lua52"))]
-    pub fn luaopen_coroutine(L: *mut lua_State) -> c_int;
-    pub fn luaopen_table(L: *mut lua_State) -> c_int;
-    pub fn luaopen_io(L: *mut lua_State) -> c_int;
-    pub fn luaopen_os(L: *mut lua_State) -> c_int;
-    pub fn luaopen_string(L: *mut lua_State) -> c_int;
-    #[cfg(feature = "lua53")]
-    pub fn luaopen_utf8(L: *mut lua_State) -> c_int;
-    #[cfg(feature = "lua52")]
-    pub fn luaopen_bit32(L: *mut lua_State) -> c_int;
-    pub fn luaopen_math(L: *mut lua_State) -> c_int;
-    pub fn luaopen_debug(L: *mut lua_State) -> c_int;
-    pub fn luaopen_package(L: *mut lua_State) -> c_int;
-    #[cfg(feature = "luajit")]
-    pub fn luaopen_bit(L: *mut lua_State) -> c_int;
-    #[cfg(feature = "luajit")]
-    pub fn luaopen_jit(L: *mut lua_State) -> c_int;
-    #[cfg(feature = "luajit")]
-    pub fn luaopen_ffi(L: *mut lua_State) -> c_int;
-
-    pub fn luaL_openlibs(L: *mut lua_State);
-}

src/ffi/mod.rs

@@ -1,252 +0,0 @@
-// The MIT License (MIT)
-//
-// Copyright (c) 2019 A. Orlenko
-// Copyright (c) 2014 J.C. Moyer
-//
-// Permission is hereby granted, free of charge, to any person obtaining a copy
-// of this software and associated documentation files (the "Software"), to deal
-// in the Software without restriction, including without limitation the rights
-// to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
-// copies of the Software, and to permit persons to whom the Software is
-// furnished to do so, subject to the following conditions:
-//
-// The above copyright notice and this permission notice shall be included in
-// all copies or substantial portions of the Software.
-//
-// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
-// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
-// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
-// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
-// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
-// OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
-// THE SOFTWARE.
-
-//! Low level bindings to Lua.
-
-#![allow(non_camel_case_types, non_snake_case, dead_code)]
-
-use std::os::raw::c_int;
-
-// This is more or less in the order it appears in the Lua manual, with the
-// exception of constants, which appear scattered throughout the manual text.
-
-// C API types
-pub use self::lua::{
-    lua_Alloc, lua_CFunction, lua_Debug, lua_Hook, lua_Integer, lua_Number, lua_Reader, lua_State,
-    lua_Unsigned, lua_Writer,
-};
-
-#[cfg(feature = "lua53")]
-pub use self::lua::{lua_KContext, lua_KFunction};
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-pub use self::lua::lua_setfenv;
-
-// C API functions
-pub use self::lua::{
-    lua_absindex,
-    lua_arith,
-    lua_atpanic,
-    lua_call,
-    lua_checkstack,
-    lua_close,
-    lua_compare,
-    lua_concat,
-    lua_copy,
-    lua_createtable,
-    lua_dump,
-    lua_error,
-    lua_gc,
-    lua_getallocf,
-    lua_getextraspace,
-    lua_getfield,
-    lua_getglobal,
-    lua_gethook,
-    lua_gethookcount,
-    lua_gethookmask,
-    lua_geti,
-    lua_getinfo,
-    lua_getlocal,
-    lua_getmetatable,
-    lua_getstack,
-    lua_gettable,
-    lua_gettop,
-    lua_getupvalue,
-    lua_getuservalue,
-    lua_insert,
-    lua_isboolean,
-    lua_iscfunction,
-    lua_isfunction,
-    lua_isinteger,
-    lua_islightuserdata,
-    lua_isnil,
-    lua_isnone,
-    lua_isnoneornil,
-    lua_isnumber,
-    lua_isstring,
-    lua_istable,
-    lua_isthread,
-    lua_isuserdata,
-    lua_len,
-    lua_load,
-    lua_newstate,
-    lua_newtable,
-    lua_newthread,
-    lua_newuserdata,
-    lua_next,
-    lua_pcall,
-    lua_pop,
-    lua_pushboolean,
-    lua_pushcclosure,
-    lua_pushcfunction,
-    lua_pushfstring,
-    lua_pushglobaltable,
-    lua_pushinteger,
-    lua_pushlightuserdata,
-    lua_pushliteral,
-    lua_pushlstring,
-    lua_pushnil,
-    lua_pushnumber,
-    lua_pushstring,
-    lua_pushthread,
-    lua_pushvalue,
-    // omitted: lua_pushvfstring
-    lua_rawequal,
-    lua_rawget,
-    lua_rawgeti,
-    lua_rawgetp,
-    lua_rawlen,
-    lua_rawset,
-    lua_rawseti,
-    lua_rawsetp,
-    lua_register,
-    lua_remove,
-    lua_replace,
-    lua_resume,
-    lua_rotate,
-    lua_setallocf,
-    lua_setfield,
-    lua_setglobal,
-    lua_sethook,
-    lua_seti,
-    lua_setlocal,
-    lua_setmetatable,
-    lua_settable,
-    lua_settop,
-    lua_setupvalue,
-    lua_setuservalue,
-    lua_status,
-    lua_stringtonumber,
-    lua_toboolean,
-    lua_tocfunction,
-    lua_tointeger,
-    lua_tointegerx,
-    lua_tolstring,
-    lua_tonumber,
-    lua_tonumberx,
-    lua_topointer,
-    lua_tostring,
-    lua_tothread,
-    lua_touserdata,
-    lua_type,
-    lua_typename,
-    lua_upvalueindex,
-    lua_xmove,
-    lua_yield,
-};
-
-#[cfg(feature = "lua53")]
-pub use self::lua::{lua_isyieldable, lua_version};
-
-#[cfg(any(feature = "lua53", feature = "lua52"))]
-pub use self::lua::{lua_callk, lua_pcallk, lua_upvalueid, lua_upvaluejoin, lua_yieldk};
-
-// auxiliary library types
-pub use self::lauxlib::luaL_Reg;
-
-// auxiliary library functions
-pub use self::lauxlib::{
-    luaL_argcheck, luaL_argerror, luaL_callmeta, luaL_checkany, luaL_checkint, luaL_checkinteger,
-    luaL_checklong, luaL_checklstring, luaL_checknumber, luaL_checkoption, luaL_checkstack,
-    luaL_checkstring, luaL_checktype, luaL_checkudata, luaL_checkversion, luaL_dofile,
-    luaL_dostring, luaL_error, luaL_getmetafield, luaL_getmetatable, luaL_getsubtable, luaL_gsub,
-    luaL_len, luaL_loadbuffer, luaL_loadbufferx, luaL_loadfile, luaL_loadstring, luaL_newlib,
-    luaL_newlibtable, luaL_newmetatable, luaL_newstate, luaL_optint, luaL_optinteger, luaL_optlong,
-    luaL_optlstring, luaL_optnumber, luaL_optstring, luaL_ref, luaL_requiref, luaL_setfuncs,
-    luaL_setmetatable, luaL_testudata, luaL_tolstring, luaL_traceback, luaL_typename, luaL_unref,
-    luaL_where,
-};
-
-#[cfg(any(feature = "lua53", feature = "lua52"))]
-pub use self::lauxlib::{luaL_execresult, luaL_fileresult, luaL_loadfilex};
-
-// lualib.h functions
-pub use self::lualib::{
-    luaL_openlibs, luaopen_base, luaopen_debug, luaopen_io, luaopen_math, luaopen_os,
-    luaopen_package, luaopen_string, luaopen_table,
-};
-
-#[cfg(feature = "lua53")]
-pub use self::lualib::{luaopen_coroutine, luaopen_utf8};
-
-#[cfg(feature = "lua52")]
-pub use self::lualib::{luaopen_bit32, luaopen_coroutine};
-
-#[cfg(feature = "luajit")]
-pub use self::lualib::{luaopen_bit, luaopen_ffi, luaopen_jit};
-
-// constants from lua.h
-pub use self::lua::{
-    LUA_ERRERR, LUA_ERRMEM, LUA_ERRRUN, LUA_ERRSYNTAX, LUA_GCCOLLECT, LUA_GCCOUNT, LUA_GCCOUNTB,
-    LUA_GCRESTART, LUA_GCSETPAUSE, LUA_GCSETSTEPMUL, LUA_GCSTEP, LUA_GCSTOP, LUA_HOOKCALL,
-    LUA_HOOKCOUNT, LUA_HOOKLINE, LUA_HOOKRET, LUA_HOOKTAILCALL, LUA_MASKCALL, LUA_MASKCOUNT,
-    LUA_MASKLINE, LUA_MASKRET, LUA_MINSTACK, LUA_MULTRET, LUA_OK, LUA_OPADD, LUA_OPDIV, LUA_OPEQ,
-    LUA_OPLE, LUA_OPLT, LUA_OPMOD, LUA_OPMUL, LUA_OPPOW, LUA_OPSUB, LUA_OPUNM, LUA_REGISTRYINDEX,
-    LUA_TBOOLEAN, LUA_TFUNCTION, LUA_TLIGHTUSERDATA, LUA_TNIL, LUA_TNONE, LUA_TNUMBER, LUA_TSTRING,
-    LUA_TTABLE, LUA_TTHREAD, LUA_TUSERDATA, LUA_YIELD,
-};
-
-#[cfg(feature = "lua53")]
-pub use self::lua::{
-    LUA_OPBAND, LUA_OPBNOT, LUA_OPBOR, LUA_OPBXOR, LUA_OPIDIV, LUA_OPSHL, LUA_OPSHR,
-};
-
-#[cfg(any(feature = "lua53", feature = "lua52"))]
-pub use self::lua::{LUA_ERRGCMM, LUA_GCISRUNNING, LUA_RIDX_GLOBALS, LUA_RIDX_MAINTHREAD};
-
-#[cfg(any(feature = "lua51", feature = "luajit"))]
-pub use self::lua::{LUA_ENVIRONINDEX, LUA_GLOBALSINDEX};
-
-// constants from lauxlib.h
-pub use self::lauxlib::{LUA_ERRFILE, LUA_NOREF, LUA_REFNIL};
-
-// constants from lualib.h
-pub use self::lualib::{
-    LUA_COLIBNAME, LUA_DBLIBNAME, LUA_IOLIBNAME, LUA_LOADLIBNAME, LUA_MATHLIBNAME, LUA_OSLIBNAME,
-    LUA_STRLIBNAME, LUA_TABLIBNAME,
-};
-
-#[cfg(feature = "lua53")]
-pub use self::lualib::LUA_UTF8LIBNAME;
-
-#[cfg(any(feature = "lua52", feature = "luajit"))]
-pub use self::lualib::LUA_BITLIBNAME;
-
-#[cfg(feature = "luajit")]
-pub use self::lualib::{LUA_FFILIBNAME, LUA_JITLIBNAME};
-
-// Not actually defined in lua.h / luaconf.h
-pub const LUA_MAX_UPVALUES: c_int = 255;
-
-#[allow(unused_imports, dead_code, non_camel_case_types)]
-mod glue {
-    include!(concat!(env!("OUT_DIR"), "/glue.rs"));
-}
-
-#[cfg(any(feature = "lua52", feature = "lua51", feature = "luajit"))]
-mod compat53;
-
-mod lauxlib;
-mod lua;
-mod luaconf;
-mod lualib;

src/function.rs

@@ -1,19 +1,69 @@
-use std::os::raw::c_int;
-use std::ptr;
+use std::cell::RefCell;
+use std::os::raw::{c_int, c_void};
+use std::{mem, ptr, slice};
 
 use crate::error::{Error, Result};
-use crate::ffi;
-use crate::types::LuaRef;
+use crate::state::Lua;
+use crate::table::Table;
+use crate::traits::{FromLuaMulti, IntoLua, IntoLuaMulti, LuaNativeFn, LuaNativeFnMut};
+use crate::types::{Callback, LuaType, MaybeSend, ValueRef};
 use crate::util::{
-    assert_stack, check_stack, error_traceback, pop_error, protect_lua_closure, StackGuard,
+    assert_stack, check_stack, linenumber_to_usize, pop_error, ptr_to_lossy_str, ptr_to_str, StackGuard,
+};
+use crate::value::Value;
+
+#[cfg(feature = "async")]
+use {
+    crate::thread::AsyncThread,
+    crate::traits::LuaNativeAsyncFn,
+    crate::types::AsyncCallback,
+    std::future::{self, Future},
+    std::pin::Pin,
+    std::task::{Context, Poll},
 };
-use crate::value::{FromLuaMulti, MultiValue, ToLuaMulti};
 
 /// Handle to an internal Lua function.
-#[derive(Clone, Debug)]
-pub struct Function<'lua>(pub(crate) LuaRef<'lua>);
+#[derive(Clone, Debug, PartialEq)]
+pub struct Function(pub(crate) ValueRef);
 
-impl<'lua> Function<'lua> {
+/// Contains information about a function.
+///
+/// Please refer to the [`Lua Debug Interface`] for more information.
+///
+/// [`Lua Debug Interface`]: https://www.lua.org/manual/5.4/manual.html#4.7
+#[derive(Clone, Debug)]
+pub struct FunctionInfo {
+    /// A (reasonable) name of the function (`None` if the name cannot be found).
+    pub name: Option<String>,
+    /// Explains the `name` field (can be `global`/`local`/`method`/`field`/`upvalue`/etc).
+    ///
+    /// Always `None` for Luau.
+    pub name_what: Option<&'static str>,
+    /// A string `Lua` if the function is a Lua function, `C` if it is a C function, `main` if it is
+    /// the main part of a chunk.
+    pub what: &'static str,
+    /// Source of the chunk that created the function.
+    pub source: Option<String>,
+    /// A "printable" version of `source`, to be used in error messages.
+    pub short_src: Option<String>,
+    /// The line number where the definition of the function starts.
+    pub line_defined: Option<usize>,
+    /// The line number where the definition of the function ends (not set by Luau).
+    pub last_line_defined: Option<usize>,
+}
+
+/// Luau function coverage snapshot.
+#[cfg(any(feature = "luau", doc))]
+#[cfg_attr(docsrs, doc(cfg(feature = "luau")))]
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub struct CoverageInfo {
+    pub function: Option<String>,
+    pub line_defined: i32,
+    pub depth: i32,
+    pub hits: Vec<i32>,
+}
+
+impl Function {
     /// Calls the function, passing `args` as function arguments.
     ///
     /// The function's return values are converted to the generic type `R`.
@@ -30,7 +80,7 @@ impl<'lua> Function<'lua> {
     ///
     /// let tostring: Function = globals.get("tostring")?;
     ///
-    /// assert_eq!(tostring.call::<_, String>(123)?, "123");
+    /// assert_eq!(tostring.call::<String>(123)?, "123");
     ///
     /// # Ok(())
     /// # }
@@ -49,41 +99,76 @@ impl<'lua> Function<'lua> {
     ///         end
     /// "#).eval()?;
     ///
-    /// assert_eq!(sum.call::<_, u32>((3, 4))?, 3 + 4);
+    /// assert_eq!(sum.call::<u32>((3, 4))?, 3 + 4);
     ///
     /// # Ok(())
     /// # }
     /// ```
-    pub fn call<A: ToLuaMulti<'lua>, R: FromLuaMulti<'lua>>(&self, args: A) -> Result<R> {
-        let lua = self.0.lua;
+    pub fn call<R: FromLuaMulti>(&self, args: impl IntoLuaMulti) -> Result<R> {
+        let lua = self.0.lua.lock();
+        let state = lua.state();
+        unsafe {
+            let _sg = StackGuard::new(state);
+            check_stack(state, 2)?;
 
-        let args = args.to_lua_multi(lua)?;
-        let nargs = args.len() as c_int;
-
-        let results = unsafe {
-            let _sg = StackGuard::new(lua.state);
-            check_stack(lua.state, nargs + 3)?;
-
-            ffi::lua_pushcfunction(lua.state, error_traceback);
-            let stack_start = ffi::lua_gettop(lua.state);
+            // Push error handler
+            lua.push_error_traceback();
+            let stack_start = ffi::lua_gettop(state);
+            // Push function and the arguments
             lua.push_ref(&self.0);
-            for arg in args {
-                lua.push_value(arg)?;
-            }
-            let ret = ffi::lua_pcall(lua.state, nargs, ffi::LUA_MULTRET, stack_start);
+            let nargs = args.push_into_stack_multi(&lua)?;
+            // Call the function
+            let ret = ffi::lua_pcall(state, nargs, ffi::LUA_MULTRET, stack_start);
             if ret != ffi::LUA_OK {
-                return Err(pop_error(lua.state, ret));
+                return Err(pop_error(state, ret));
             }
-            let nresults = ffi::lua_gettop(lua.state) - stack_start;
-            let mut results = MultiValue::new();
-            assert_stack(lua.state, 2);
-            for _ in 0..nresults {
-                results.push_front(lua.pop_value());
-            }
-            ffi::lua_pop(lua.state, 1);
-            results
-        };
-        R::from_lua_multi(results, lua)
+            // Get the results
+            let nresults = ffi::lua_gettop(state) - stack_start;
+            R::from_stack_multi(nresults, &lua)
+        }
+    }
+
+    /// Returns a future that, when polled, calls `self`, passing `args` as function arguments,
+    /// and drives the execution.
+    ///
+    /// Internally it wraps the function to an [`AsyncThread`]. The returned type implements
+    /// `Future<Output = Result<R>>` and can be awaited.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use std::time::Duration;
+    /// # use mlua::{Lua, Result};
+    /// # #[tokio::main]
+    /// # async fn main() -> Result<()> {
+    /// # let lua = Lua::new();
+    ///
+    /// let sleep = lua.create_async_function(move |_lua, n: u64| async move {
+    ///     tokio::time::sleep(Duration::from_millis(n)).await;
+    ///     Ok(())
+    /// })?;
+    ///
+    /// sleep.call_async::<()>(10).await?;
+    ///
+    /// # Ok(())
+    /// # }
+    /// ```
+    ///
+    /// [`AsyncThread`]: crate::AsyncThread
+    #[cfg(feature = "async")]
+    #[cfg_attr(docsrs, doc(cfg(feature = "async")))]
+    pub fn call_async<R>(&self, args: impl IntoLuaMulti) -> AsyncCallFuture<R>
+    where
+        R: FromLuaMulti,
+    {
+        let lua = self.0.lua.lock();
+        AsyncCallFuture(unsafe {
+            lua.create_recycled_thread(self).and_then(|th| {
+                let mut th = th.into_async(args)?;
+                th.set_recyclable(true);
+                Ok(th)
+            })
+        })
     }
 
     /// Returns a function that, when called, calls `self`, passing `args` as the first set of
@@ -105,64 +190,506 @@ impl<'lua> Function<'lua> {
     /// "#).eval()?;
     ///
     /// let bound_a = sum.bind(1)?;
-    /// assert_eq!(bound_a.call::<_, u32>(2)?, 1 + 2);
+    /// assert_eq!(bound_a.call::<u32>(2)?, 1 + 2);
     ///
     /// let bound_a_and_b = sum.bind(13)?.bind(57)?;
-    /// assert_eq!(bound_a_and_b.call::<_, u32>(())?, 13 + 57);
+    /// assert_eq!(bound_a_and_b.call::<u32>(())?, 13 + 57);
     ///
     /// # Ok(())
     /// # }
     /// ```
-    pub fn bind<A: ToLuaMulti<'lua>>(&self, args: A) -> Result<Function<'lua>> {
-        unsafe extern "C" fn bind_call_impl(state: *mut ffi::lua_State) -> c_int {
+    pub fn bind(&self, args: impl IntoLuaMulti) -> Result<Function> {
+        unsafe extern "C-unwind" fn args_wrapper_impl(state: *mut ffi::lua_State) -> c_int {
             let nargs = ffi::lua_gettop(state);
-            let nbinds = ffi::lua_tointeger(state, ffi::lua_upvalueindex(2)) as c_int;
-            ffi::luaL_checkstack(state, nbinds + 2, ptr::null());
-
-            ffi::lua_settop(state, nargs + nbinds + 1);
-            ffi::lua_rotate(state, -(nargs + nbinds + 1), nbinds + 1);
-
-            ffi::lua_pushvalue(state, ffi::lua_upvalueindex(1));
-            ffi::lua_replace(state, 1);
+            let nbinds = ffi::lua_tointeger(state, ffi::lua_upvalueindex(1)) as c_int;
+            ffi::luaL_checkstack(state, nbinds, ptr::null());
 
             for i in 0..nbinds {
-                ffi::lua_pushvalue(state, ffi::lua_upvalueindex(i + 3));
-                ffi::lua_replace(state, i + 2);
+                ffi::lua_pushvalue(state, ffi::lua_upvalueindex(i + 2));
+            }
+            if nargs > 0 {
+                ffi::lua_rotate(state, 1, nbinds);
             }
 
-            ffi::lua_call(state, nargs + nbinds, ffi::LUA_MULTRET);
-            ffi::lua_gettop(state)
+            nargs + nbinds
         }
 
-        let lua = self.0.lua;
+        let lua = self.0.lua.lock();
+        let state = lua.state();
 
-        let args = args.to_lua_multi(lua)?;
+        let args = args.into_lua_multi(lua.lua())?;
         let nargs = args.len() as c_int;
 
-        if nargs + 2 > ffi::LUA_MAX_UPVALUES {
+        if nargs == 0 {
+            return Ok(self.clone());
+        }
+
+        if nargs + 1 > ffi::LUA_MAX_UPVALUES {
             return Err(Error::BindError);
         }
 
-        unsafe {
-            let _sg = StackGuard::new(lua.state);
-            check_stack(lua.state, nargs + 5)?;
-            lua.push_ref(&self.0);
-            ffi::lua_pushinteger(lua.state, nargs as ffi::lua_Integer);
-            for arg in args {
+        let args_wrapper = unsafe {
+            let _sg = StackGuard::new(state);
+            check_stack(state, nargs + 3)?;
+
+            ffi::lua_pushinteger(state, nargs as ffi::lua_Integer);
+            for arg in &args {
                 lua.push_value(arg)?;
             }
-
-            protect_lua_closure(lua.state, nargs + 2, 1, |state| {
-                ffi::lua_pushcclosure(state, bind_call_impl, nargs + 2);
+            protect_lua!(state, nargs + 1, 1, fn(state) {
+                ffi::lua_pushcclosure(state, args_wrapper_impl, ffi::lua_gettop(state));
             })?;
 
+            Function(lua.pop_ref())
+        };
+
+        let lua = lua.lua();
+        lua.load(
+            r#"
+            local func, args_wrapper = ...
+            return function(...)
+                return func(args_wrapper(...))
+            end
+            "#,
+        )
+        .try_cache()
+        .set_name("=__mlua_bind")
+        .call((self, args_wrapper))
+    }
+
+    /// Returns the environment of the Lua function.
+    ///
+    /// By default Lua functions shares a global environment.
+    ///
+    /// This function always returns `None` for Rust/C functions.
+    pub fn environment(&self) -> Option<Table> {
+        let lua = self.0.lua.lock();
+        let state = lua.state();
+        unsafe {
+            let _sg = StackGuard::new(state);
+            assert_stack(state, 1);
+
+            lua.push_ref(&self.0);
+            if ffi::lua_iscfunction(state, -1) != 0 {
+                return None;
+            }
+
+            #[cfg(any(feature = "lua51", feature = "luajit", feature = "luau"))]
+            ffi::lua_getfenv(state, -1);
+            #[cfg(any(feature = "lua54", feature = "lua53", feature = "lua52"))]
+            for i in 1..=255 {
+                // Traverse upvalues until we find the _ENV one
+                match ffi::lua_getupvalue(state, -1, i) {
+                    s if s.is_null() => break,
+                    s if std::ffi::CStr::from_ptr(s as _) == c"_ENV" => break,
+                    _ => ffi::lua_pop(state, 1),
+                }
+            }
+
+            if ffi::lua_type(state, -1) != ffi::LUA_TTABLE {
+                return None;
+            }
+            Some(Table(lua.pop_ref()))
+        }
+    }
+
+    /// Sets the environment of the Lua function.
+    ///
+    /// The environment is a table that is used as the global environment for the function.
+    /// Returns `true` if environment successfully changed, `false` otherwise.
+    ///
+    /// This function does nothing for Rust/C functions.
+    pub fn set_environment(&self, env: Table) -> Result<bool> {
+        let lua = self.0.lua.lock();
+        let state = lua.state();
+        unsafe {
+            let _sg = StackGuard::new(state);
+            check_stack(state, 2)?;
+
+            lua.push_ref(&self.0);
+            if ffi::lua_iscfunction(state, -1) != 0 {
+                return Ok(false);
+            }
+
+            #[cfg(any(feature = "lua51", feature = "luajit", feature = "luau"))]
+            {
+                lua.push_ref(&env.0);
+                ffi::lua_setfenv(state, -2);
+            }
+            #[cfg(any(feature = "lua54", feature = "lua53", feature = "lua52"))]
+            for i in 1..=255 {
+                match ffi::lua_getupvalue(state, -1, i) {
+                    s if s.is_null() => return Ok(false),
+                    s if std::ffi::CStr::from_ptr(s as _) == c"_ENV" => {
+                        ffi::lua_pop(state, 1);
+                        // Create an anonymous function with the new environment
+                        let f_with_env = lua
+                            .lua()
+                            .load("return _ENV")
+                            .set_environment(env)
+                            .try_cache()
+                            .into_function()?;
+                        lua.push_ref(&f_with_env.0);
+                        ffi::lua_upvaluejoin(state, -2, i, -1, 1);
+                        break;
+                    }
+                    _ => ffi::lua_pop(state, 1),
+                }
+            }
+
+            Ok(true)
+        }
+    }
+
+    /// Returns information about the function.
+    ///
+    /// Corresponds to the `>Sn` what mask for [`lua_getinfo`] when applied to the function.
+    ///
+    /// [`lua_getinfo`]: https://www.lua.org/manual/5.4/manual.html#lua_getinfo
+    pub fn info(&self) -> FunctionInfo {
+        let lua = self.0.lua.lock();
+        let state = lua.state();
+        unsafe {
+            let _sg = StackGuard::new(state);
+            assert_stack(state, 1);
+
+            let mut ar: ffi::lua_Debug = mem::zeroed();
+            lua.push_ref(&self.0);
+            #[cfg(not(feature = "luau"))]
+            let res = ffi::lua_getinfo(state, cstr!(">Sn"), &mut ar);
+            #[cfg(feature = "luau")]
+            let res = ffi::lua_getinfo(state, -1, cstr!("sn"), &mut ar);
+            mlua_assert!(res != 0, "lua_getinfo failed with `>Sn`");
+
+            FunctionInfo {
+                name: ptr_to_lossy_str(ar.name).map(|s| s.into_owned()),
+                #[cfg(not(feature = "luau"))]
+                name_what: match ptr_to_str(ar.namewhat) {
+                    Some("") => None,
+                    val => val,
+                },
+                #[cfg(feature = "luau")]
+                name_what: None,
+                what: ptr_to_str(ar.what).unwrap_or("main"),
+                source: ptr_to_lossy_str(ar.source).map(|s| s.into_owned()),
+                #[cfg(not(feature = "luau"))]
+                short_src: ptr_to_lossy_str(ar.short_src.as_ptr()).map(|s| s.into_owned()),
+                #[cfg(feature = "luau")]
+                short_src: ptr_to_lossy_str(ar.short_src).map(|s| s.into_owned()),
+                line_defined: linenumber_to_usize(ar.linedefined),
+                #[cfg(not(feature = "luau"))]
+                last_line_defined: linenumber_to_usize(ar.lastlinedefined),
+                #[cfg(feature = "luau")]
+                last_line_defined: None,
+            }
+        }
+    }
+
+    /// Dumps the function as a binary chunk.
+    ///
+    /// If `strip` is true, the binary representation may not include all debug information
+    /// about the function, to save space.
+    ///
+    /// For Luau a [`Compiler`] can be used to compile Lua chunks to bytecode.
+    ///
+    /// [`Compiler`]: crate::chunk::Compiler
+    #[cfg(not(feature = "luau"))]
+    #[cfg_attr(docsrs, doc(cfg(not(feature = "luau"))))]
+    pub fn dump(&self, strip: bool) -> Vec<u8> {
+        unsafe extern "C-unwind" fn writer(
+            _state: *mut ffi::lua_State,
+            buf: *const c_void,
+            buf_len: usize,
+            data: *mut c_void,
+        ) -> c_int {
+            let data = &mut *(data as *mut Vec<u8>);
+            let buf = slice::from_raw_parts(buf as *const u8, buf_len);
+            data.extend_from_slice(buf);
+            0
+        }
+
+        let lua = self.0.lua.lock();
+        let state = lua.state();
+        let mut data: Vec<u8> = Vec::new();
+        unsafe {
+            let _sg = StackGuard::new(state);
+            assert_stack(state, 1);
+
+            lua.push_ref(&self.0);
+            let data_ptr = &mut data as *mut Vec<u8> as *mut c_void;
+            ffi::lua_dump(state, writer, data_ptr, strip as i32);
+            ffi::lua_pop(state, 1);
+        }
+
+        data
+    }
+
+    /// Retrieves recorded coverage information about this Lua function including inner calls.
+    ///
+    /// This function takes a callback as an argument and calls it providing [`CoverageInfo`]
+    /// snapshot per each executed inner function.
+    ///
+    /// Recording of coverage information is controlled by [`Compiler::set_coverage_level`] option.
+    ///
+    /// [`Compiler::set_coverage_level`]: crate::chunk::Compiler::set_coverage_level
+    #[cfg(any(feature = "luau", doc))]
+    #[cfg_attr(docsrs, doc(cfg(feature = "luau")))]
+    pub fn coverage<F>(&self, func: F)
+    where
+        F: FnMut(CoverageInfo),
+    {
+        use std::ffi::CStr;
+        use std::os::raw::c_char;
+
+        unsafe extern "C-unwind" fn callback<F: FnMut(CoverageInfo)>(
+            data: *mut c_void,
+            function: *const c_char,
+            line_defined: c_int,
+            depth: c_int,
+            hits: *const c_int,
+            size: usize,
+        ) {
+            let function = if !function.is_null() {
+                Some(CStr::from_ptr(function).to_string_lossy().to_string())
+            } else {
+                None
+            };
+            let rust_callback = &*(data as *const RefCell<F>);
+            if let Ok(mut rust_callback) = rust_callback.try_borrow_mut() {
+                // Call the Rust callback with CoverageInfo
+                rust_callback(CoverageInfo {
+                    function,
+                    line_defined,
+                    depth,
+                    hits: slice::from_raw_parts(hits, size).to_vec(),
+                });
+            }
+        }
+
+        let lua = self.0.lua.lock();
+        let state = lua.state();
+        unsafe {
+            let _sg = StackGuard::new(state);
+            assert_stack(state, 1);
+
+            lua.push_ref(&self.0);
+            let func = RefCell::new(func);
+            let func_ptr = &func as *const RefCell<F> as *mut c_void;
+            ffi::lua_getcoverage(state, -1, func_ptr, callback::<F>);
+        }
+    }
+
+    /// Converts this function to a generic C pointer.
+    ///
+    /// There is no way to convert the pointer back to its original value.
+    ///
+    /// Typically this function is used only for hashing and debug information.
+    #[inline]
+    pub fn to_pointer(&self) -> *const c_void {
+        self.0.to_pointer()
+    }
+
+    /// Creates a deep clone of the Lua function.
+    ///
+    /// Copies the function prototype and all its upvalues to the
+    /// newly created function.
+    /// This function returns shallow clone (same handle) for Rust/C functions.
+    #[cfg(any(feature = "luau", doc))]
+    #[cfg_attr(docsrs, doc(cfg(feature = "luau")))]
+    pub fn deep_clone(&self) -> Result<Self> {
+        let lua = self.0.lua.lock();
+        let state = lua.state();
+        unsafe {
+            let _sg = StackGuard::new(state);
+            check_stack(state, 2)?;
+
+            lua.push_ref(&self.0);
+            if ffi::lua_iscfunction(state, -1) != 0 {
+                return Ok(self.clone());
+            }
+
+            if lua.unlikely_memory_error() {
+                ffi::lua_clonefunction(state, -1);
+            } else {
+                protect_lua!(state, 1, 1, fn(state) ffi::lua_clonefunction(state, -1))?;
+            }
             Ok(Function(lua.pop_ref()))
         }
     }
 }
 
-impl<'lua> PartialEq for Function<'lua> {
-    fn eq(&self, other: &Self) -> bool {
-        self.0 == other.0
+struct WrappedFunction(pub(crate) Callback);
+
+#[cfg(feature = "async")]
+struct WrappedAsyncFunction(pub(crate) AsyncCallback);
+
+impl Function {
+    /// Wraps a Rust function or closure, returning an opaque type that implements [`IntoLua`]
+    /// trait.
+    #[inline]
+    pub fn wrap<F, A, R>(func: F) -> impl IntoLua
+    where
+        F: LuaNativeFn<A, Output = Result<R>> + MaybeSend + 'static,
+        A: FromLuaMulti,
+        R: IntoLuaMulti,
+    {
+        WrappedFunction(Box::new(move |lua, nargs| unsafe {
+            let args = A::from_stack_args(nargs, 1, None, lua)?;
+            func.call(args)?.push_into_stack_multi(lua)
+        }))
+    }
+
+    /// Wraps a Rust mutable closure, returning an opaque type that implements [`IntoLua`] trait.
+    pub fn wrap_mut<F, A, R>(func: F) -> impl IntoLua
+    where
+        F: LuaNativeFnMut<A, Output = Result<R>> + MaybeSend + 'static,
+        A: FromLuaMulti,
+        R: IntoLuaMulti,
+    {
+        let func = RefCell::new(func);
+        WrappedFunction(Box::new(move |lua, nargs| unsafe {
+            let mut func = func.try_borrow_mut().map_err(|_| Error::RecursiveMutCallback)?;
+            let args = A::from_stack_args(nargs, 1, None, lua)?;
+            func.call(args)?.push_into_stack_multi(lua)
+        }))
+    }
+
+    /// Wraps a Rust function or closure, returning an opaque type that implements [`IntoLua`]
+    /// trait.
+    ///
+    /// This function is similar to [`Function::wrap`] but any returned `Result` will be converted
+    /// to a `ok, err` tuple without throwing an exception.
+    #[inline]
+    pub fn wrap_raw<F, A>(func: F) -> impl IntoLua
+    where
+        F: LuaNativeFn<A> + MaybeSend + 'static,
+        A: FromLuaMulti,
+    {
+        WrappedFunction(Box::new(move |lua, nargs| unsafe {
+            let args = A::from_stack_args(nargs, 1, None, lua)?;
+            func.call(args).push_into_stack_multi(lua)
+        }))
+    }
+
+    /// Wraps a Rust mutable closure, returning an opaque type that implements [`IntoLua`] trait.
+    ///
+    /// This function is similar to [`Function::wrap_mut`] but any returned `Result` will be
+    /// converted to a `ok, err` tuple without throwing an exception.
+    #[inline]
+    pub fn wrap_raw_mut<F, A>(func: F) -> impl IntoLua
+    where
+        F: LuaNativeFnMut<A> + MaybeSend + 'static,
+        A: FromLuaMulti,
+    {
+        let func = RefCell::new(func);
+        WrappedFunction(Box::new(move |lua, nargs| unsafe {
+            let mut func = func.try_borrow_mut().map_err(|_| Error::RecursiveMutCallback)?;
+            let args = A::from_stack_args(nargs, 1, None, lua)?;
+            func.call(args).push_into_stack_multi(lua)
+        }))
+    }
+
+    /// Wraps a Rust async function or closure, returning an opaque type that implements [`IntoLua`]
+    /// trait.
+    #[cfg(feature = "async")]
+    #[cfg_attr(docsrs, doc(cfg(feature = "async")))]
+    pub fn wrap_async<F, A, R>(func: F) -> impl IntoLua
+    where
+        F: LuaNativeAsyncFn<A, Output = Result<R>> + MaybeSend + 'static,
+        A: FromLuaMulti,
+        R: IntoLuaMulti,
+    {
+        WrappedAsyncFunction(Box::new(move |rawlua, nargs| unsafe {
+            let args = match A::from_stack_args(nargs, 1, None, rawlua) {
+                Ok(args) => args,
+                Err(e) => return Box::pin(future::ready(Err(e))),
+            };
+            let lua = rawlua.lua();
+            let fut = func.call(args);
+            Box::pin(async move { fut.await?.push_into_stack_multi(lua.raw_lua()) })
+        }))
+    }
+
+    /// Wraps a Rust async function or closure, returning an opaque type that implements [`IntoLua`]
+    /// trait.
+    ///
+    /// This function is similar to [`Function::wrap_async`] but any returned `Result` will be
+    /// converted to a `ok, err` tuple without throwing an exception.
+    #[cfg(feature = "async")]
+    #[cfg_attr(docsrs, doc(cfg(feature = "async")))]
+    pub fn wrap_raw_async<F, A>(func: F) -> impl IntoLua
+    where
+        F: LuaNativeAsyncFn<A> + MaybeSend + 'static,
+        A: FromLuaMulti,
+    {
+        WrappedAsyncFunction(Box::new(move |rawlua, nargs| unsafe {
+            let args = match A::from_stack_args(nargs, 1, None, rawlua) {
+                Ok(args) => args,
+                Err(e) => return Box::pin(future::ready(Err(e))),
+            };
+            let lua = rawlua.lua();
+            let fut = func.call(args);
+            Box::pin(async move { fut.await.push_into_stack_multi(lua.raw_lua()) })
+        }))
     }
 }
+
+impl IntoLua for WrappedFunction {
+    #[inline]
+    fn into_lua(self, lua: &Lua) -> Result<Value> {
+        lua.lock().create_callback(self.0).map(Value::Function)
+    }
+}
+
+#[cfg(feature = "async")]
+impl IntoLua for WrappedAsyncFunction {
+    #[inline]
+    fn into_lua(self, lua: &Lua) -> Result<Value> {
+        lua.lock().create_async_callback(self.0).map(Value::Function)
+    }
+}
+
+impl LuaType for Function {
+    const TYPE_ID: c_int = ffi::LUA_TFUNCTION;
+}
+
+#[cfg(feature = "async")]
+#[must_use = "futures do nothing unless you `.await` or poll them"]
+pub struct AsyncCallFuture<R: FromLuaMulti>(Result<AsyncThread<R>>);
+
+#[cfg(feature = "async")]
+impl<R: FromLuaMulti> AsyncCallFuture<R> {
+    pub(crate) fn error(err: Error) -> Self {
+        AsyncCallFuture(Err(err))
+    }
+}
+
+#[cfg(feature = "async")]
+impl<R: FromLuaMulti> Future for AsyncCallFuture<R> {
+    type Output = Result<R>;
+
+    fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
+        // Safety: We're not moving any pinned data
+        let this = unsafe { self.get_unchecked_mut() };
+        match &mut this.0 {
+            Ok(thread) => {
+                let pinned_thread = unsafe { Pin::new_unchecked(thread) };
+                pinned_thread.poll(cx)
+            }
+            Err(err) => Poll::Ready(Err(err.clone())),
+        }
+    }
+}
+
+#[cfg(test)]
+mod assertions {
+    use super::*;
+
+    #[cfg(not(feature = "send"))]
+    static_assertions::assert_not_impl_any!(Function: Send);
+    #[cfg(feature = "send")]
+    static_assertions::assert_impl_all!(Function: Send, Sync);
+
+    #[cfg(all(feature = "async", feature = "send"))]
+    static_assertions::assert_impl_all!(AsyncCallFuture<()>: Send);
+}

src/lib.rs

@@ -10,10 +10,10 @@
 //!
 //! # Converting data
 //!
-//! The [`ToLua`] and [`FromLua`] traits allow conversion from Rust types to Lua values and vice
+//! The [`IntoLua`] and [`FromLua`] traits allow conversion from Rust types to Lua values and vice
 //! versa. They are implemented for many data structures found in Rust's standard library.
 //!
-//! For more general conversions, the [`ToLuaMulti`] and [`FromLuaMulti`] traits allow converting
+//! For more general conversions, the [`IntoLuaMulti`] and [`FromLuaMulti`] traits allow converting
 //! between Rust types and *any number* of Lua values.
 //!
 //! Most code in `mlua` is generic over implementors of those traits, so in most places the normal
@@ -23,55 +23,252 @@
 //!
 //! The [`UserData`] trait can be implemented by user-defined types to make them available to Lua.
 //! Methods and operators to be used from Lua can be added using the [`UserDataMethods`] API.
+//! Fields are supported using the [`UserDataFields`] API.
+//!
+//! # Serde support
+//!
+//! The [`LuaSerdeExt`] trait implemented for [`Lua`] allows conversion from Rust types to Lua
+//! values and vice versa using serde. Any user defined data type that implements
+//! [`serde::Serialize`] or [`serde::Deserialize`] can be converted.
+//! For convenience, additional functionality to handle `NULL` values and arrays is provided.
+//!
+//! The [`Value`] enum and other types implement [`serde::Serialize`] trait to support serializing
+//! Lua values into Rust values.
+//!
+//! Requires `feature = "serde"`.
+//!
+//! # Async/await support
+//!
+//! The [`Lua::create_async_function`] allows creating non-blocking functions that returns
+//! [`Future`]. Lua code with async capabilities can be executed by [`Function::call_async`] family
+//! of functions or polling [`AsyncThread`] using any runtime (eg. Tokio).
+//!
+//! Requires `feature = "async"`.
+//!
+//! # `Send` and `Sync` support
+//!
+//! By default `mlua` is `!Send`. This can be changed by enabling `feature = "send"` that adds
+//! `Send` requirement to Rust functions and [`UserData`] types.
+//!
+//! In this case [`Lua`] object and their types can be send or used from other threads. Internally
+//! access to Lua VM is synchronized using a reentrant mutex that can be locked many times within
+//! the same thread.
 //!
 //! [Lua programming language]: https://www.lua.org/
-//! [`Lua`]: struct.Lua.html
-//! [executing]: struct.Lua.html#method.exec
-//! [evaluating]: struct.Lua.html#method.eval
-//! [globals]: struct.Lua.html#method.globals
-//! [`ToLua`]: trait.ToLua.html
-//! [`FromLua`]: trait.FromLua.html
-//! [`ToLuaMulti`]: trait.ToLuaMulti.html
-//! [`FromLuaMulti`]: trait.FromLuaMulti.html
-//! [`UserData`]: trait.UserData.html
-//! [`UserDataMethods`]: trait.UserDataMethods.html
+//! [executing]: crate::Chunk::exec
+//! [evaluating]: crate::Chunk::eval
+//! [globals]: crate::Lua::globals
+//! [`Future`]: std::future::Future
+//! [`serde::Serialize`]: https://docs.serde.rs/serde/ser/trait.Serialize.html
+//! [`serde::Deserialize`]: https://docs.serde.rs/serde/de/trait.Deserialize.html
 
 // Deny warnings inside doc tests / examples. When this isn't present, rustdoc doesn't show *any*
 // warnings at all.
-#![doc(test(attr(deny(warnings))))]
+#![cfg_attr(docsrs, feature(doc_cfg))]
+#![cfg_attr(not(send), allow(clippy::arc_with_non_send_sync))]
+#![allow(clippy::ptr_eq)]
+#![allow(unsafe_op_in_unsafe_fn)]
 
 #[macro_use]
 mod macros;
 
+mod buffer;
+mod chunk;
 mod conversion;
+mod debug;
 mod error;
-mod ffi;
 mod function;
-mod lua;
+#[cfg(any(feature = "luau", doc))]
+mod luau;
+mod memory;
 mod multi;
 mod scope;
+mod state;
 mod stdlib;
 mod string;
 mod table;
 mod thread;
+mod traits;
 mod types;
 mod userdata;
 mod util;
 mod value;
-
-pub use crate::ffi::lua_State;
-
-pub use crate::error::{Error, ExternalError, ExternalResult, Result};
-pub use crate::function::Function;
-pub use crate::lua::{Chunk, Lua};
-pub use crate::multi::Variadic;
-pub use crate::scope::Scope;
-pub use crate::stdlib::StdLib;
-pub use crate::string::String;
-pub use crate::table::{Table, TablePairs, TableSequence};
-pub use crate::thread::{Thread, ThreadStatus};
-pub use crate::types::{Integer, LightUserData, Number, RegistryKey};
-pub use crate::userdata::{AnyUserData, MetaMethod, UserData, UserDataMethods};
-pub use crate::value::{FromLua, FromLuaMulti, MultiValue, Nil, ToLua, ToLuaMulti, Value};
+mod vector;
 
 pub mod prelude;
+
+pub use bstr::BString;
+pub use ffi::{self, lua_CFunction, lua_State};
+
+pub use crate::chunk::{AsChunk, Chunk, ChunkMode};
+pub use crate::debug::{Debug, DebugEvent, DebugNames, DebugSource, DebugStack};
+pub use crate::error::{Error, ErrorContext, ExternalError, ExternalResult, Result};
+pub use crate::function::{Function, FunctionInfo};
+pub use crate::multi::{MultiValue, Variadic};
+pub use crate::scope::Scope;
+pub use crate::state::{GCMode, Lua, LuaOptions, WeakLua};
+pub use crate::stdlib::StdLib;
+pub use crate::string::{BorrowedBytes, BorrowedStr, String};
+pub use crate::table::{Table, TablePairs, TableSequence};
+pub use crate::thread::{Thread, ThreadStatus};
+pub use crate::traits::{
+    FromLua, FromLuaMulti, IntoLua, IntoLuaMulti, LuaNativeFn, LuaNativeFnMut, ObjectLike,
+};
+pub use crate::types::{
+    AppDataRef, AppDataRefMut, Either, Integer, LightUserData, MaybeSend, Number, RegistryKey, VmState,
+};
+pub use crate::userdata::{
+    AnyUserData, MetaMethod, UserData, UserDataFields, UserDataMetatable, UserDataMethods, UserDataRef,
+    UserDataRefMut, UserDataRegistry,
+};
+pub use crate::value::{Nil, Value};
+
+#[cfg(not(feature = "luau"))]
+pub use crate::debug::HookTriggers;
+
+#[cfg(any(feature = "luau", doc))]
+#[cfg_attr(docsrs, doc(cfg(feature = "luau")))]
+pub use crate::{
+    buffer::Buffer,
+    chunk::{CompileConstant, Compiler},
+    function::CoverageInfo,
+    luau::{NavigateError, Require, TextRequirer},
+    vector::Vector,
+};
+
+#[cfg(feature = "async")]
+#[cfg_attr(docsrs, doc(cfg(feature = "async")))]
+pub use crate::{thread::AsyncThread, traits::LuaNativeAsyncFn};
+
+#[cfg(feature = "serde")]
+#[doc(inline)]
+pub use crate::serde::{de::Options as DeserializeOptions, ser::Options as SerializeOptions, LuaSerdeExt};
+
+#[cfg(feature = "serde")]
+#[cfg_attr(docsrs, doc(cfg(feature = "serde")))]
+pub mod serde;
+
+#[cfg(feature = "mlua_derive")]
+#[allow(unused_imports)]
+#[macro_use]
+extern crate mlua_derive;
+
+/// Create a type that implements [`AsChunk`] and can capture Rust variables.
+///
+/// This macro allows to write Lua code directly in Rust code.
+///
+/// Rust variables can be referenced from Lua using `$` prefix, as shown in the example below.
+/// User's Rust types needs to implement [`UserData`] or [`IntoLua`] traits.
+///
+/// Captured variables are **moved** into the chunk.
+///
+/// ```
+/// use mlua::{Lua, Result, chunk};
+///
+/// fn main() -> Result<()> {
+///     let lua = Lua::new();
+///     let name = "Rustacean";
+///     lua.load(chunk! {
+///         print("hello, " .. $name)
+///     }).exec()
+/// }
+/// ```
+///
+/// ## Syntax issues
+///
+/// Since the Rust tokenizer will tokenize Lua code, this imposes some restrictions.
+/// The main thing to remember is:
+///
+/// - Use double quoted strings (`""`) instead of single quoted strings (`''`).
+///
+///   (Single quoted strings only work if they contain a single character, since in Rust,
+///   `'a'` is a character literal).
+///
+/// - Using Lua comments `--` is not desirable in **stable** Rust and can have bad side effects.
+///
+///   This is because procedural macros have Line/Column information available only in
+///   **nightly** Rust. Instead, Lua chunks represented as a big single line of code in stable Rust.
+///
+///   As workaround, Rust comments `//` can be used.
+///
+/// Other minor limitations:
+///
+/// - Certain escape codes in string literals don't work. (Specifically: `\a`, `\b`, `\f`, `\v`,
+///   `\123` (octal escape codes), `\u`, and `\U`).
+///
+///   These are accepted: : `\\`, `\n`, `\t`, `\r`, `\xAB` (hex escape codes), and `\0`.
+///
+/// - The `//` (floor division) operator is unusable, as its start a comment.
+///
+/// Everything else should work.
+#[cfg(feature = "macros")]
+#[cfg_attr(docsrs, doc(cfg(feature = "macros")))]
+pub use mlua_derive::chunk;
+
+/// Derive [`FromLua`] for a Rust type.
+///
+/// Current implementation generate code that takes [`UserData`] value, borrow it (of the Rust type)
+/// and clone.
+#[cfg(feature = "macros")]
+#[cfg_attr(docsrs, doc(cfg(feature = "macros")))]
+pub use mlua_derive::FromLua;
+
+/// Registers Lua module entrypoint.
+///
+/// You can register multiple entrypoints as required.
+///
+/// ```ignore
+/// use mlua::{Lua, Result, Table};
+///
+/// #[mlua::lua_module]
+/// fn my_module(lua: &Lua) -> Result<Table> {
+///     let exports = lua.create_table()?;
+///     exports.set("hello", "world")?;
+///     Ok(exports)
+/// }
+/// ```
+///
+/// Internally in the code above the compiler defines C function `luaopen_my_module`.
+///
+/// You can also pass options to the attribute:
+///
+/// * name - name of the module, defaults to the name of the function
+///
+/// ```ignore
+/// #[mlua::lua_module(name = "alt_module")]
+/// fn my_module(lua: &Lua) -> Result<Table> {
+///     ...
+/// }
+/// ```
+///
+/// * skip_memory_check - skip memory allocation checks for some operations.
+///
+/// In module mode, mlua runs in unknown environment and cannot say are there any memory
+/// limits or not. As result, some operations that require memory allocation runs in
+/// protected mode. Setting this attribute will improve performance of such operations
+/// with risk of having uncaught exceptions and memory leaks.
+///
+/// ```ignore
+/// #[mlua::lua_module(skip_memory_check)]
+/// fn my_module(lua: &Lua) -> Result<Table> {
+///     ...
+/// }
+/// ```
+#[cfg(all(feature = "mlua_derive", any(feature = "module", doc)))]
+#[cfg_attr(docsrs, doc(cfg(feature = "module")))]
+pub use mlua_derive::lua_module;
+
+#[cfg(all(feature = "module", feature = "send"))]
+compile_error!("`send` feature is not supported in module mode");
+
+pub(crate) mod private {
+    use super::*;
+
+    pub trait Sealed {}
+
+    impl Sealed for Error {}
+    impl<T> Sealed for std::result::Result<T, Error> {}
+    impl Sealed for Lua {}
+    impl Sealed for Table {}
+    impl Sealed for AnyUserData {}
+}

src/luau/mod.rs

@@ -0,0 +1,99 @@
+use std::ffi::CStr;
+use std::os::raw::c_int;
+use std::ptr;
+
+use crate::chunk::ChunkMode;
+use crate::error::Result;
+use crate::function::Function;
+use crate::state::{callback_error_ext, ExtraData, Lua};
+use crate::traits::{FromLuaMulti, IntoLua};
+use crate::types::MaybeSend;
+
+pub use require::{NavigateError, Require, TextRequirer};
+
+// Since Luau has some missing standard functions, we re-implement them here
+
+impl Lua {
+    /// Create a custom Luau `require` function using provided [`Require`] implementation to find
+    /// and load modules.
+    #[cfg(any(feature = "luau", doc))]
+    #[cfg_attr(docsrs, doc(cfg(feature = "luau")))]
+    pub fn create_require_function<R: Require + MaybeSend + 'static>(&self, require: R) -> Result<Function> {
+        require::create_require_function(self, require)
+    }
+
+    pub(crate) unsafe fn configure_luau(&self) -> Result<()> {
+        let globals = self.globals();
+
+        globals.raw_set("collectgarbage", self.create_c_function(lua_collectgarbage)?)?;
+        globals.raw_set("loadstring", self.create_c_function(lua_loadstring)?)?;
+
+        // Set `_VERSION` global to include version number
+        // The environment variable `LUAU_VERSION` set by the build script
+        if let Some(version) = ffi::luau_version() {
+            globals.raw_set("_VERSION", format!("Luau {version}"))?;
+        }
+
+        // Enable default `require` implementation
+        let require = self.create_require_function(require::TextRequirer::new())?;
+        self.globals().raw_set("require", require)?;
+
+        Ok(())
+    }
+}
+
+unsafe extern "C-unwind" fn lua_collectgarbage(state: *mut ffi::lua_State) -> c_int {
+    let option = ffi::luaL_optstring(state, 1, cstr!("collect"));
+    let option = CStr::from_ptr(option);
+    let arg = ffi::luaL_optinteger(state, 2, 0);
+    let is_sandboxed = (*ExtraData::get(state)).sandboxed;
+    match option.to_str() {
+        Ok("collect") if !is_sandboxed => {
+            ffi::lua_gc(state, ffi::LUA_GCCOLLECT, 0);
+            0
+        }
+        Ok("stop") if !is_sandboxed => {
+            ffi::lua_gc(state, ffi::LUA_GCSTOP, 0);
+            0
+        }
+        Ok("restart") if !is_sandboxed => {
+            ffi::lua_gc(state, ffi::LUA_GCRESTART, 0);
+            0
+        }
+        Ok("count") => {
+            let kbytes = ffi::lua_gc(state, ffi::LUA_GCCOUNT, 0) as ffi::lua_Number;
+            let kbytes_rem = ffi::lua_gc(state, ffi::LUA_GCCOUNTB, 0) as ffi::lua_Number;
+            ffi::lua_pushnumber(state, kbytes + kbytes_rem / 1024.0);
+            1
+        }
+        Ok("step") if !is_sandboxed => {
+            let res = ffi::lua_gc(state, ffi::LUA_GCSTEP, arg as _);
+            ffi::lua_pushboolean(state, res);
+            1
+        }
+        Ok("isrunning") if !is_sandboxed => {
+            let res = ffi::lua_gc(state, ffi::LUA_GCISRUNNING, 0);
+            ffi::lua_pushboolean(state, res);
+            1
+        }
+        _ => ffi::luaL_error(state, cstr!("collectgarbage called with invalid option")),
+    }
+}
+
+unsafe extern "C-unwind" fn lua_loadstring(state: *mut ffi::lua_State) -> c_int {
+    callback_error_ext(state, ptr::null_mut(), false, move |extra, nargs| {
+        let rawlua = (*extra).raw_lua();
+        let (chunk, chunk_name) =
+            <(String, Option<String>)>::from_stack_args(nargs, 1, Some("loadstring"), rawlua)?;
+        let chunk_name = chunk_name.as_deref().unwrap_or("=(loadstring)");
+        (rawlua.lua())
+            .load(chunk)
+            .set_name(chunk_name)
+            .set_mode(ChunkMode::Text)
+            .into_function()?
+            .push_into_stack(rawlua)?;
+        Ok(1)
+    })
+}
+
+mod require;

src/luau/require.rs

@@ -0,0 +1,688 @@
+use std::cell::RefCell;
+use std::collections::VecDeque;
+use std::ffi::CStr;
+use std::io::Result as IoResult;
+use std::ops::{Deref, DerefMut};
+use std::os::raw::{c_char, c_int, c_void};
+use std::path::{Component, Path, PathBuf};
+use std::result::Result as StdResult;
+use std::{env, fmt, fs, mem, ptr};
+
+use crate::error::{Error, Result};
+use crate::function::Function;
+use crate::state::{callback_error_ext, Lua};
+use crate::table::Table;
+use crate::types::MaybeSend;
+
+/// An error that can occur during navigation in the Luau `require-by-string` system.
+#[cfg(any(feature = "luau", doc))]
+#[cfg_attr(docsrs, doc(cfg(feature = "luau")))]
+#[derive(Debug, Clone)]
+pub enum NavigateError {
+    Ambiguous,
+    NotFound,
+    Other(Error),
+}
+
+#[cfg(feature = "luau")]
+trait IntoNavigateResult {
+    fn into_nav_result(self) -> Result<ffi::luarequire_NavigateResult>;
+}
+
+#[cfg(feature = "luau")]
+impl IntoNavigateResult for StdResult<(), NavigateError> {
+    fn into_nav_result(self) -> Result<ffi::luarequire_NavigateResult> {
+        match self {
+            Ok(()) => Ok(ffi::luarequire_NavigateResult::Success),
+            Err(NavigateError::Ambiguous) => Ok(ffi::luarequire_NavigateResult::Ambiguous),
+            Err(NavigateError::NotFound) => Ok(ffi::luarequire_NavigateResult::NotFound),
+            Err(NavigateError::Other(err)) => Err(err),
+        }
+    }
+}
+
+impl From<Error> for NavigateError {
+    fn from(err: Error) -> Self {
+        NavigateError::Other(err)
+    }
+}
+
+#[cfg(feature = "luau")]
+type WriteResult = ffi::luarequire_WriteResult;
+
+/// A trait for handling modules loading and navigation in the Luau `require-by-string` system.
+#[cfg(any(feature = "luau", doc))]
+#[cfg_attr(docsrs, doc(cfg(feature = "luau")))]
+pub trait Require {
+    /// Returns `true` if "require" is permitted for the given chunk name.
+    fn is_require_allowed(&self, chunk_name: &str) -> bool;
+
+    /// Resets the internal state to point at the requirer module.
+    fn reset(&mut self, chunk_name: &str) -> StdResult<(), NavigateError>;
+
+    /// Resets the internal state to point at an aliased module.
+    ///
+    /// This function received an exact path from a configuration file.
+    /// It's only called when an alias's path cannot be resolved relative to its
+    /// configuration file.
+    fn jump_to_alias(&mut self, path: &str) -> StdResult<(), NavigateError>;
+
+    // Navigate to parent directory
+    fn to_parent(&mut self) -> StdResult<(), NavigateError>;
+
+    /// Navigate to the given child directory.
+    fn to_child(&mut self, name: &str) -> StdResult<(), NavigateError>;
+
+    /// Returns whether the context is currently pointing at a module
+    fn has_module(&self) -> bool;
+
+    /// Provides a cache key representing the current module.
+    ///
+    /// This function is only called if `has_module` returns true.
+    fn cache_key(&self) -> String;
+
+    /// Returns whether a configuration is present in the current context.
+    fn has_config(&self) -> bool;
+
+    /// Returns the contents of the configuration file in the current context.
+    ///
+    /// This function is only called if `has_config` returns true.
+    fn config(&self) -> IoResult<Vec<u8>>;
+
+    /// Returns a loader function for the current module, that when called, loads the module
+    /// and returns the result.
+    ///
+    /// Loader can be sync or async.
+    /// This function is only called if `has_module` returns true.
+    fn loader(&self, lua: &Lua) -> Result<Function>;
+}
+
+impl fmt::Debug for dyn Require {
+    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
+        write!(f, "<dyn Require>")
+    }
+}
+
+/// The standard implementation of Luau `require-by-string` navigation.
+#[derive(Default, Debug)]
+pub struct TextRequirer {
+    /// An absolute path to the current Luau module (not mapped to a physical file)
+    abs_path: PathBuf,
+    /// A relative path to the current Luau module (not mapped to a physical file)
+    rel_path: PathBuf,
+    /// A physical path to the current Luau module, which is a file or a directory with an
+    /// `init.lua(u)` file
+    resolved_path: Option<PathBuf>,
+}
+
+impl TextRequirer {
+    /// The prefix used for chunk names in the require system.
+    /// Only chunk names starting with this prefix are allowed to be used in `require`.
+    const CHUNK_PREFIX: &str = "@";
+
+    /// The file extensions that are considered valid for Luau modules.
+    const FILE_EXTENSIONS: &[&str] = &["luau", "lua"];
+
+    /// Creates a new `TextRequirer` instance.
+    pub fn new() -> Self {
+        Self::default()
+    }
+
+    fn normalize_chunk_name(chunk_name: &str) -> &str {
+        if let Some((path, line)) = chunk_name.rsplit_once(':') {
+            if line.parse::<u32>().is_ok() {
+                return path;
+            }
+        }
+        chunk_name
+    }
+
+    // Normalizes the path by removing unnecessary components
+    fn normalize_path(path: &Path) -> PathBuf {
+        let mut components = VecDeque::new();
+
+        for comp in path.components() {
+            match comp {
+                Component::Prefix(..) | Component::RootDir => {
+                    components.push_back(comp);
+                }
+                Component::CurDir => {}
+                Component::ParentDir => {
+                    if matches!(components.back(), None | Some(Component::ParentDir)) {
+                        components.push_back(Component::ParentDir);
+                    } else if matches!(components.back(), Some(Component::Normal(..))) {
+                        components.pop_back();
+                    }
+                }
+                Component::Normal(..) => components.push_back(comp),
+            }
+        }
+
+        if matches!(components.front(), None | Some(Component::Normal(..))) {
+            components.push_front(Component::CurDir);
+        }
+
+        // Join the components back together
+        components.into_iter().collect()
+    }
+
+    /// Resolve a Luau module path to a physical file or directory.
+    ///
+    /// Empty directories without init files are considered valid as "intermediate" directories.
+    fn resolve_module(path: &Path) -> StdResult<Option<PathBuf>, NavigateError> {
+        let mut found_path = None;
+
+        if path.components().next_back() != Some(Component::Normal("init".as_ref())) {
+            let current_ext = (path.extension().and_then(|s| s.to_str()))
+                .map(|s| format!("{s}."))
+                .unwrap_or_default();
+            for ext in Self::FILE_EXTENSIONS {
+                let candidate = path.with_extension(format!("{current_ext}{ext}"));
+                if candidate.is_file() && found_path.replace(candidate).is_some() {
+                    return Err(NavigateError::Ambiguous);
+                }
+            }
+        }
+        if path.is_dir() {
+            for component in Self::FILE_EXTENSIONS.iter().map(|ext| format!("init.{ext}")) {
+                let candidate = path.join(component);
+                if candidate.is_file() && found_path.replace(candidate).is_some() {
+                    return Err(NavigateError::Ambiguous);
+                }
+            }
+
+            if found_path.is_none() {
+                // Directories without init files are considered valid "intermediate" path
+                return Ok(None);
+            }
+        }
+
+        Ok(Some(found_path.ok_or(NavigateError::NotFound)?))
+    }
+}
+
+impl Require for TextRequirer {
+    fn is_require_allowed(&self, chunk_name: &str) -> bool {
+        chunk_name.starts_with(Self::CHUNK_PREFIX)
+    }
+
+    fn reset(&mut self, chunk_name: &str) -> StdResult<(), NavigateError> {
+        if !chunk_name.starts_with(Self::CHUNK_PREFIX) {
+            return Err(NavigateError::NotFound);
+        }
+        let chunk_name = Self::normalize_chunk_name(&chunk_name[1..]);
+        let chunk_path = Self::normalize_path(chunk_name.as_ref());
+
+        if chunk_path.extension() == Some("rs".as_ref()) {
+            // Special case for Rust source files, reset to the current directory
+            let chunk_filename = chunk_path.file_name().unwrap();
+            let cwd = env::current_dir().map_err(|_| NavigateError::NotFound)?;
+            self.abs_path = Self::normalize_path(&cwd.join(chunk_filename));
+            self.rel_path = ([Component::CurDir, Component::Normal(chunk_filename)].into_iter()).collect();
+            self.resolved_path = None;
+
+            return Ok(());
+        }
+
+        if chunk_path.is_absolute() {
+            let resolved_path = Self::resolve_module(&chunk_path)?;
+            self.abs_path = chunk_path.clone();
+            self.rel_path = chunk_path;
+            self.resolved_path = resolved_path;
+        } else {
+            // Relative path
+            let cwd = env::current_dir().map_err(|_| NavigateError::NotFound)?;
+            let abs_path = Self::normalize_path(&cwd.join(&chunk_path));
+            let resolved_path = Self::resolve_module(&abs_path)?;
+            self.abs_path = abs_path;
+            self.rel_path = chunk_path;
+            self.resolved_path = resolved_path;
+        }
+
+        Ok(())
+    }
+
+    fn jump_to_alias(&mut self, path: &str) -> StdResult<(), NavigateError> {
+        let path = Self::normalize_path(path.as_ref());
+        let resolved_path = Self::resolve_module(&path)?;
+
+        self.abs_path = path.clone();
+        self.rel_path = path;
+        self.resolved_path = resolved_path;
+
+        Ok(())
+    }
+
+    fn to_parent(&mut self) -> StdResult<(), NavigateError> {
+        let mut abs_path = self.abs_path.clone();
+        if !abs_path.pop() {
+            // It's important to return `NotFound` if we reached the root, as it's a "recoverable" error if we
+            // cannot go beyond the root directory.
+            // Luau "require-by-string` has a special logic to search for config file to resolve aliases.
+            return Err(NavigateError::NotFound);
+        }
+        let mut rel_parent = self.rel_path.clone();
+        rel_parent.pop();
+        let resolved_path = Self::resolve_module(&abs_path)?;
+
+        self.abs_path = abs_path;
+        self.rel_path = Self::normalize_path(&rel_parent);
+        self.resolved_path = resolved_path;
+
+        Ok(())
+    }
+
+    fn to_child(&mut self, name: &str) -> StdResult<(), NavigateError> {
+        let abs_path = self.abs_path.join(name);
+        let rel_path = self.rel_path.join(name);
+        let resolved_path = Self::resolve_module(&abs_path)?;
+
+        self.abs_path = abs_path;
+        self.rel_path = rel_path;
+        self.resolved_path = resolved_path;
+
+        Ok(())
+    }
+
+    fn has_module(&self) -> bool {
+        (self.resolved_path.as_deref())
+            .map(Path::is_file)
+            .unwrap_or(false)
+    }
+
+    fn cache_key(&self) -> String {
+        self.resolved_path.as_deref().unwrap().display().to_string()
+    }
+
+    fn has_config(&self) -> bool {
+        self.abs_path.is_dir() && self.abs_path.join(".luaurc").is_file()
+    }
+
+    fn config(&self) -> IoResult<Vec<u8>> {
+        fs::read(self.abs_path.join(".luaurc"))
+    }
+
+    fn loader(&self, lua: &Lua) -> Result<Function> {
+        let name = format!("@{}", self.rel_path.display());
+        lua.load(self.resolved_path.as_deref().unwrap())
+            .set_name(name)
+            .into_function()
+    }
+}
+
+struct Context(Box<dyn Require>);
+
+impl Deref for Context {
+    type Target = dyn Require;
+
+    fn deref(&self) -> &Self::Target {
+        &*self.0
+    }
+}
+
+impl DerefMut for Context {
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        &mut *self.0
+    }
+}
+
+macro_rules! try_borrow {
+    ($state:expr, $ctx:expr) => {
+        match (*($ctx as *const RefCell<Context>)).try_borrow() {
+            Ok(ctx) => ctx,
+            Err(_) => ffi::luaL_error($state, cstr!("require context is already borrowed")),
+        }
+    };
+}
+
+macro_rules! try_borrow_mut {
+    ($state:expr, $ctx:expr) => {
+        match (*($ctx as *const RefCell<Context>)).try_borrow_mut() {
+            Ok(ctx) => ctx,
+            Err(_) => ffi::luaL_error($state, cstr!("require context is already borrowed")),
+        }
+    };
+}
+
+#[cfg(feature = "luau")]
+pub(super) unsafe extern "C-unwind" fn init_config(config: *mut ffi::luarequire_Configuration) {
+    if config.is_null() {
+        return;
+    }
+
+    unsafe extern "C-unwind" fn is_require_allowed(
+        state: *mut ffi::lua_State,
+        ctx: *mut c_void,
+        requirer_chunkname: *const c_char,
+    ) -> bool {
+        if requirer_chunkname.is_null() {
+            return false;
+        }
+
+        let this = try_borrow!(state, ctx);
+        let chunk_name = CStr::from_ptr(requirer_chunkname).to_string_lossy();
+        this.is_require_allowed(&chunk_name)
+    }
+
+    unsafe extern "C-unwind" fn reset(
+        state: *mut ffi::lua_State,
+        ctx: *mut c_void,
+        requirer_chunkname: *const c_char,
+    ) -> ffi::luarequire_NavigateResult {
+        let mut this = try_borrow_mut!(state, ctx);
+        let chunk_name = CStr::from_ptr(requirer_chunkname).to_string_lossy();
+        callback_error_ext(state, ptr::null_mut(), true, move |_, _| {
+            this.reset(&chunk_name).into_nav_result()
+        })
+    }
+
+    unsafe extern "C-unwind" fn jump_to_alias(
+        state: *mut ffi::lua_State,
+        ctx: *mut c_void,
+        path: *const c_char,
+    ) -> ffi::luarequire_NavigateResult {
+        let mut this = try_borrow_mut!(state, ctx);
+        let path = CStr::from_ptr(path).to_string_lossy();
+        callback_error_ext(state, ptr::null_mut(), true, move |_, _| {
+            this.jump_to_alias(&path).into_nav_result()
+        })
+    }
+
+    unsafe extern "C-unwind" fn to_parent(
+        state: *mut ffi::lua_State,
+        ctx: *mut c_void,
+    ) -> ffi::luarequire_NavigateResult {
+        let mut this = try_borrow_mut!(state, ctx);
+        callback_error_ext(state, ptr::null_mut(), true, move |_, _| {
+            this.to_parent().into_nav_result()
+        })
+    }
+
+    unsafe extern "C-unwind" fn to_child(
+        state: *mut ffi::lua_State,
+        ctx: *mut c_void,
+        name: *const c_char,
+    ) -> ffi::luarequire_NavigateResult {
+        let mut this = try_borrow_mut!(state, ctx);
+        let name = CStr::from_ptr(name).to_string_lossy();
+        callback_error_ext(state, ptr::null_mut(), true, move |_, _| {
+            this.to_child(&name).into_nav_result()
+        })
+    }
+
+    unsafe extern "C-unwind" fn is_module_present(state: *mut ffi::lua_State, ctx: *mut c_void) -> bool {
+        let this = try_borrow!(state, ctx);
+        this.has_module()
+    }
+
+    unsafe extern "C-unwind" fn get_chunkname(
+        _state: *mut ffi::lua_State,
+        _ctx: *mut c_void,
+        buffer: *mut c_char,
+        buffer_size: usize,
+        size_out: *mut usize,
+    ) -> WriteResult {
+        write_to_buffer(buffer, buffer_size, size_out, &[])
+    }
+
+    unsafe extern "C-unwind" fn get_loadname(
+        _state: *mut ffi::lua_State,
+        _ctx: *mut c_void,
+        buffer: *mut c_char,
+        buffer_size: usize,
+        size_out: *mut usize,
+    ) -> WriteResult {
+        write_to_buffer(buffer, buffer_size, size_out, &[])
+    }
+
+    unsafe extern "C-unwind" fn get_cache_key(
+        state: *mut ffi::lua_State,
+        ctx: *mut c_void,
+        buffer: *mut c_char,
+        buffer_size: usize,
+        size_out: *mut usize,
+    ) -> WriteResult {
+        let this = try_borrow!(state, ctx);
+        let cache_key = this.cache_key();
+        write_to_buffer(buffer, buffer_size, size_out, cache_key.as_bytes())
+    }
+
+    unsafe extern "C-unwind" fn is_config_present(state: *mut ffi::lua_State, ctx: *mut c_void) -> bool {
+        let this = try_borrow!(state, ctx);
+        this.has_config()
+    }
+
+    unsafe extern "C-unwind" fn get_config(
+        state: *mut ffi::lua_State,
+        ctx: *mut c_void,
+        buffer: *mut c_char,
+        buffer_size: usize,
+        size_out: *mut usize,
+    ) -> WriteResult {
+        let this = try_borrow!(state, ctx);
+        let config = callback_error_ext(state, ptr::null_mut(), true, move |_, _| Ok(this.config()?));
+        write_to_buffer(buffer, buffer_size, size_out, &config)
+    }
+
+    unsafe extern "C-unwind" fn load(
+        state: *mut ffi::lua_State,
+        ctx: *mut c_void,
+        _path: *const c_char,
+        _chunkname: *const c_char,
+        _loadname: *const c_char,
+    ) -> c_int {
+        let this = try_borrow!(state, ctx);
+        callback_error_ext(state, ptr::null_mut(), true, move |extra, _| {
+            let rawlua = (*extra).raw_lua();
+            let loader = this.loader(rawlua.lua())?;
+            rawlua.push(loader)?;
+            Ok(1)
+        })
+    }
+
+    (*config).is_require_allowed = is_require_allowed;
+    (*config).reset = reset;
+    (*config).jump_to_alias = jump_to_alias;
+    (*config).to_parent = to_parent;
+    (*config).to_child = to_child;
+    (*config).is_module_present = is_module_present;
+    (*config).get_chunkname = get_chunkname;
+    (*config).get_loadname = get_loadname;
+    (*config).get_cache_key = get_cache_key;
+    (*config).is_config_present = is_config_present;
+    (*config).get_alias = None;
+    (*config).get_config = Some(get_config);
+    (*config).load = load;
+}
+
+/// Helper function to write data to a buffer
+#[cfg(feature = "luau")]
+unsafe fn write_to_buffer(
+    buffer: *mut c_char,
+    buffer_size: usize,
+    size_out: *mut usize,
+    data: &[u8],
+) -> WriteResult {
+    // the buffer must be null terminated as it's a c++ `std::string` data() buffer
+    let is_null_terminated = data.last() == Some(&0);
+    *size_out = data.len() + if is_null_terminated { 0 } else { 1 };
+    if *size_out > buffer_size {
+        return WriteResult::BufferTooSmall;
+    }
+    ptr::copy_nonoverlapping(data.as_ptr(), buffer as *mut _, data.len());
+    if !is_null_terminated {
+        *buffer.add(data.len()) = 0;
+    }
+    WriteResult::Success
+}
+
+#[cfg(feature = "luau")]
+pub(super) fn create_require_function<R: Require + MaybeSend + 'static>(
+    lua: &Lua,
+    require: R,
+) -> Result<Function> {
+    unsafe extern "C-unwind" fn find_current_file(state: *mut ffi::lua_State) -> c_int {
+        let mut ar: ffi::lua_Debug = mem::zeroed();
+        for level in 2.. {
+            if ffi::lua_getinfo(state, level, cstr!("s"), &mut ar) == 0 {
+                ffi::luaL_error(state, cstr!("require is not supported in this context"));
+            }
+            if CStr::from_ptr(ar.what) != c"C" {
+                break;
+            }
+        }
+        ffi::lua_pushstring(state, ar.source);
+        1
+    }
+
+    unsafe extern "C-unwind" fn get_cache_key(state: *mut ffi::lua_State) -> c_int {
+        let ctx = ffi::lua_touserdata(state, ffi::lua_upvalueindex(1));
+        let ctx = try_borrow!(state, ctx);
+        let cache_key = ctx.cache_key();
+        ffi::lua_pushlstring(state, cache_key.as_ptr() as *const _, cache_key.len());
+        1
+    }
+
+    let (get_cache_key, find_current_file, proxyrequire, registered_modules, loader_cache) = unsafe {
+        lua.exec_raw::<(Function, Function, Function, Table, Table)>((), move |state| {
+            let context = Context(Box::new(require));
+            let context_ptr = ffi::lua_newuserdata_t(state, RefCell::new(context));
+            ffi::lua_pushcclosured(state, get_cache_key, cstr!("get_cache_key"), 1);
+            ffi::lua_pushcfunctiond(state, find_current_file, cstr!("find_current_file"));
+            ffi::luarequire_pushproxyrequire(state, init_config, context_ptr as *mut _);
+            ffi::luaL_getsubtable(state, ffi::LUA_REGISTRYINDEX, ffi::LUA_REGISTERED_MODULES_TABLE);
+            ffi::luaL_getsubtable(state, ffi::LUA_REGISTRYINDEX, cstr!("__MLUA_LOADER_CACHE"));
+        })
+    }?;
+
+    unsafe extern "C-unwind" fn error(state: *mut ffi::lua_State) -> c_int {
+        ffi::luaL_where(state, 1);
+        ffi::lua_pushvalue(state, 1);
+        ffi::lua_concat(state, 2);
+        ffi::lua_error(state);
+    }
+
+    unsafe extern "C-unwind" fn r#type(state: *mut ffi::lua_State) -> c_int {
+        ffi::lua_pushstring(state, ffi::lua_typename(state, ffi::lua_type(state, 1)));
+        1
+    }
+
+    unsafe extern "C-unwind" fn to_lowercase(state: *mut ffi::lua_State) -> c_int {
+        let s = ffi::luaL_checkstring(state, 1);
+        let s = CStr::from_ptr(s);
+        if !s.to_bytes().iter().any(|&c| c.is_ascii_uppercase()) {
+            // If the string does not contain any uppercase ASCII letters, return it as is
+            return 1;
+        }
+        callback_error_ext(state, ptr::null_mut(), true, |extra, _| {
+            let s = (s.to_bytes().iter())
+                .map(|&c| c.to_ascii_lowercase())
+                .collect::<bstr::BString>();
+            (*extra).raw_lua().push(s).map(|_| 1)
+        })
+    }
+
+    let (error, r#type, to_lowercase) = unsafe {
+        lua.exec_raw::<(Function, Function, Function)>((), move |state| {
+            ffi::lua_pushcfunctiond(state, error, cstr!("error"));
+            ffi::lua_pushcfunctiond(state, r#type, cstr!("type"));
+            ffi::lua_pushcfunctiond(state, to_lowercase, cstr!("to_lowercase"));
+        })
+    }?;
+
+    // Prepare environment for the "require" function
+    let env = lua.create_table_with_capacity(0, 7)?;
+    env.raw_set("get_cache_key", get_cache_key)?;
+    env.raw_set("find_current_file", find_current_file)?;
+    env.raw_set("proxyrequire", proxyrequire)?;
+    env.raw_set("REGISTERED_MODULES", registered_modules)?;
+    env.raw_set("LOADER_CACHE", loader_cache)?;
+    env.raw_set("error", error)?;
+    env.raw_set("type", r#type)?;
+    env.raw_set("to_lowercase", to_lowercase)?;
+
+    lua.load(
+        r#"
+        local path = ...
+        if type(path) ~= "string" then
+            error("bad argument #1 to 'require' (string expected, got " .. type(path) .. ")")
+        end
+
+        -- Check if the module (path) is explicitly registered
+        local maybe_result = REGISTERED_MODULES[to_lowercase(path)]
+        if maybe_result ~= nil then
+            return maybe_result
+        end
+
+        local loader = proxyrequire(path, find_current_file())
+        local cache_key = get_cache_key()
+        -- Check if the loader result is already cached
+        local result = LOADER_CACHE[cache_key]
+        if result ~= nil then
+            return result
+        end
+
+        -- Call the loader function and cache the result
+        result = loader()
+        if result == nil then
+            result = true
+        end
+        LOADER_CACHE[cache_key] = result
+        return result
+        "#,
+    )
+    .try_cache()
+    .set_name("=__mlua_require")
+    .set_environment(env)
+    .into_function()
+}
+
+#[cfg(test)]
+mod tests {
+    use std::path::Path;
+
+    use super::TextRequirer;
+
+    #[test]
+    fn test_path_normalize() {
+        for (input, expected) in [
+            // Basic formatting checks
+            ("", "./"),
+            (".", "./"),
+            ("a/relative/path", "./a/relative/path"),
+            // Paths containing extraneous '.' and '/' symbols
+            ("./remove/extraneous/symbols/", "./remove/extraneous/symbols"),
+            ("./remove/extraneous//symbols", "./remove/extraneous/symbols"),
+            ("./remove/extraneous/symbols/.", "./remove/extraneous/symbols"),
+            ("./remove/extraneous/./symbols", "./remove/extraneous/symbols"),
+            ("../remove/extraneous/symbols/", "../remove/extraneous/symbols"),
+            ("../remove/extraneous//symbols", "../remove/extraneous/symbols"),
+            ("../remove/extraneous/symbols/.", "../remove/extraneous/symbols"),
+            ("../remove/extraneous/./symbols", "../remove/extraneous/symbols"),
+            ("/remove/extraneous/symbols/", "/remove/extraneous/symbols"),
+            ("/remove/extraneous//symbols", "/remove/extraneous/symbols"),
+            ("/remove/extraneous/symbols/.", "/remove/extraneous/symbols"),
+            ("/remove/extraneous/./symbols", "/remove/extraneous/symbols"),
+            // Paths containing '..'
+            ("./remove/me/..", "./remove"),
+            ("./remove/me/../", "./remove"),
+            ("../remove/me/..", "../remove"),
+            ("../remove/me/../", "../remove"),
+            ("/remove/me/..", "/remove"),
+            ("/remove/me/../", "/remove"),
+            ("./..", "../"),
+            ("./../", "../"),
+            ("../..", "../../"),
+            ("../../", "../../"),
+            // '..' disappears if path is absolute and component is non-erasable
+            ("/../", "/"),
+        ] {
+            let path = TextRequirer::normalize_path(input.as_ref());
+            assert_eq!(
+                &path,
+                expected.as_ref() as &Path,
+                "wrong normalization for {input}"
+            );
+        }
+    }
+}

src/macros.rs

@@ -10,26 +10,25 @@ macro_rules! bug_msg {
 
 macro_rules! cstr {
     ($s:expr) => {
-        concat!($s, "\0") as *const str as *const [::std::os::raw::c_char]
-            as *const ::std::os::raw::c_char
+        concat!($s, "\0") as *const str as *const [::std::os::raw::c_char] as *const ::std::os::raw::c_char
     };
 }
 
 macro_rules! mlua_panic {
     ($msg:expr) => {
-        panic!(bug_msg!($msg));
+        panic!(bug_msg!($msg))
     };
 
     ($msg:expr,) => {
-        mlua_panic!($msg);
+        mlua_panic!($msg)
     };
 
     ($msg:expr, $($arg:expr),+) => {
-        panic!(bug_msg!($msg), $($arg),+);
+        panic!(bug_msg!($msg), $($arg),+)
     };
 
     ($msg:expr, $($arg:expr),+,) => {
-        mlua_panic!($msg, $($arg),+);
+        mlua_panic!($msg, $($arg),+)
     };
 }
 
@@ -78,3 +77,40 @@ macro_rules! mlua_expect {
         mlua_expect!($res, $msg)
     };
 }
+
+#[cfg(feature = "module")]
+#[doc(hidden)]
+#[macro_export]
+macro_rules! require_module_feature {
+    () => {};
+}
+
+#[cfg(not(feature = "module"))]
+#[doc(hidden)]
+#[macro_export]
+macro_rules! require_module_feature {
+    () => {
+        compile_error!("Feature `module` must be enabled in the `mlua` crate");
+    };
+}
+
+macro_rules! protect_lua {
+    ($state:expr, $nargs:expr, $nresults:expr, $f:expr) => {
+        crate::util::protect_lua_closure($state, $nargs, $nresults, $f)
+    };
+
+    ($state:expr, $nargs:expr, $nresults:expr, fn($state_inner:ident) $code:expr) => {{
+        use ::std::os::raw::c_int;
+        unsafe extern "C-unwind" fn do_call($state_inner: *mut ffi::lua_State) -> c_int {
+            $code;
+            let nresults = $nresults;
+            if nresults == ::ffi::LUA_MULTRET {
+                ffi::lua_gettop($state_inner)
+            } else {
+                nresults
+            }
+        }
+
+        crate::util::protect_lua_call($state, $nargs, do_call)
+    }};
+}

src/memory.rs

@@ -0,0 +1,164 @@
+use std::alloc::{self, Layout};
+use std::os::raw::c_void;
+use std::ptr;
+
+pub(crate) static ALLOCATOR: ffi::lua_Alloc = allocator;
+
+#[repr(C)]
+#[derive(Default)]
+pub(crate) struct MemoryState {
+    used_memory: isize,
+    memory_limit: isize,
+    // Can be set to temporary ignore the memory limit.
+    // This is used when calling `lua_pushcfunction` for lua5.1/jit/luau.
+    ignore_limit: bool,
+    // Indicates that the memory limit was reached on the last allocation.
+    #[cfg(feature = "luau")]
+    limit_reached: bool,
+}
+
+impl MemoryState {
+    #[cfg(feature = "luau")]
+    #[inline]
+    pub(crate) unsafe fn get(state: *mut ffi::lua_State) -> *mut Self {
+        let mut mem_state = ptr::null_mut();
+        ffi::lua_getallocf(state, &mut mem_state);
+        mlua_assert!(!mem_state.is_null(), "Luau state has no allocator userdata");
+        mem_state as *mut MemoryState
+    }
+
+    #[cfg(not(feature = "luau"))]
+    #[rustversion::since(1.85)]
+    #[inline]
+    #[allow(clippy::incompatible_msrv)]
+    pub(crate) unsafe fn get(state: *mut ffi::lua_State) -> *mut Self {
+        let mut mem_state = ptr::null_mut();
+        if !ptr::fn_addr_eq(ffi::lua_getallocf(state, &mut mem_state), ALLOCATOR) {
+            mem_state = ptr::null_mut();
+        }
+        mem_state as *mut MemoryState
+    }
+
+    #[cfg(not(feature = "luau"))]
+    #[rustversion::before(1.85)]
+    #[inline]
+    pub(crate) unsafe fn get(state: *mut ffi::lua_State) -> *mut Self {
+        let mut mem_state = ptr::null_mut();
+        if ffi::lua_getallocf(state, &mut mem_state) != ALLOCATOR {
+            mem_state = ptr::null_mut();
+        }
+        mem_state as *mut MemoryState
+    }
+
+    #[inline]
+    pub(crate) fn used_memory(&self) -> usize {
+        self.used_memory as usize
+    }
+
+    #[inline]
+    pub(crate) fn memory_limit(&self) -> usize {
+        self.memory_limit as usize
+    }
+
+    #[inline]
+    pub(crate) fn set_memory_limit(&mut self, limit: usize) -> usize {
+        let prev_limit = self.memory_limit;
+        self.memory_limit = limit as isize;
+        prev_limit as usize
+    }
+
+    // This function is used primarily for calling `lua_pushcfunction` in lua5.1/jit/luau
+    // to bypass the memory limit (if set).
+    #[cfg(any(feature = "lua51", feature = "luajit", feature = "luau"))]
+    #[inline]
+    pub(crate) unsafe fn relax_limit_with(state: *mut ffi::lua_State, f: impl FnOnce()) {
+        let mem_state = Self::get(state);
+        if !mem_state.is_null() {
+            (*mem_state).ignore_limit = true;
+            f();
+            (*mem_state).ignore_limit = false;
+        } else {
+            f();
+        }
+    }
+
+    // Does nothing apart from calling `f()`, we don't need to bypass any limits
+    #[cfg(any(feature = "lua52", feature = "lua53", feature = "lua54"))]
+    #[inline]
+    pub(crate) unsafe fn relax_limit_with(_state: *mut ffi::lua_State, f: impl FnOnce()) {
+        f();
+    }
+
+    // Returns `true` if the memory limit was reached on the last memory operation
+    #[cfg(feature = "luau")]
+    #[inline]
+    pub(crate) unsafe fn limit_reached(state: *mut ffi::lua_State) -> bool {
+        (*Self::get(state)).limit_reached
+    }
+}
+
+unsafe extern "C" fn allocator(
+    extra: *mut c_void,
+    ptr: *mut c_void,
+    osize: usize,
+    nsize: usize,
+) -> *mut c_void {
+    let mem_state = &mut *(extra as *mut MemoryState);
+    #[cfg(feature = "luau")]
+    {
+        // Reset the flag
+        mem_state.limit_reached = false;
+    }
+
+    if nsize == 0 {
+        // Free memory
+        if !ptr.is_null() {
+            let layout = Layout::from_size_align_unchecked(osize, ffi::SYS_MIN_ALIGN);
+            alloc::dealloc(ptr as *mut u8, layout);
+            mem_state.used_memory -= osize as isize;
+        }
+        return ptr::null_mut();
+    }
+
+    // Do not allocate more than isize::MAX
+    if nsize > isize::MAX as usize {
+        return ptr::null_mut();
+    }
+
+    // Are we fit to the memory limits?
+    let mut mem_diff = nsize as isize;
+    if !ptr.is_null() {
+        mem_diff -= osize as isize;
+    }
+    let mem_limit = mem_state.memory_limit;
+    let new_used_memory = mem_state.used_memory + mem_diff;
+    if mem_limit > 0 && new_used_memory > mem_limit && !mem_state.ignore_limit {
+        #[cfg(feature = "luau")]
+        {
+            mem_state.limit_reached = true;
+        }
+        return ptr::null_mut();
+    }
+    mem_state.used_memory += mem_diff;
+
+    if ptr.is_null() {
+        // Allocate new memory
+        let new_layout = match Layout::from_size_align(nsize, ffi::SYS_MIN_ALIGN) {
+            Ok(layout) => layout,
+            Err(_) => return ptr::null_mut(),
+        };
+        let new_ptr = alloc::alloc(new_layout) as *mut c_void;
+        if new_ptr.is_null() {
+            alloc::handle_alloc_error(new_layout);
+        }
+        return new_ptr;
+    }
+
+    // Reallocate memory
+    let old_layout = Layout::from_size_align_unchecked(osize, ffi::SYS_MIN_ALIGN);
+    let new_ptr = alloc::realloc(ptr as *mut u8, old_layout, nsize) as *mut c_void;
+    if new_ptr.is_null() {
+        alloc::handle_alloc_error(old_layout);
+    }
+    new_ptr
+}

src/multi.rs

@@ -1,51 +1,212 @@
+use std::collections::{vec_deque, VecDeque};
 use std::iter::FromIterator;
+use std::mem;
 use std::ops::{Deref, DerefMut};
+use std::os::raw::c_int;
 use std::result::Result as StdResult;
 
 use crate::error::Result;
-use crate::lua::Lua;
-use crate::value::{FromLua, FromLuaMulti, MultiValue, Nil, ToLua, ToLuaMulti};
+use crate::state::{Lua, RawLua};
+use crate::traits::{FromLua, FromLuaMulti, IntoLua, IntoLuaMulti};
+use crate::util::check_stack;
+use crate::value::{Nil, Value};
 
-/// Result is convertible to `MultiValue` following the common Lua idiom of returning the result
+/// Result is convertible to [`MultiValue`] following the common Lua idiom of returning the result
 /// on success, or in the case of an error, returning `nil` and an error message.
-impl<'lua, T: ToLua<'lua>, E: ToLua<'lua>> ToLuaMulti<'lua> for StdResult<T, E> {
-    fn to_lua_multi(self, lua: &'lua Lua) -> Result<MultiValue<'lua>> {
-        let mut result = MultiValue::new();
-
+impl<T: IntoLua, E: IntoLua> IntoLuaMulti for StdResult<T, E> {
+    #[inline]
+    fn into_lua_multi(self, lua: &Lua) -> Result<MultiValue> {
         match self {
-            Ok(v) => result.push_front(v.to_lua(lua)?),
-            Err(e) => {
-                result.push_front(e.to_lua(lua)?);
-                result.push_front(Nil);
-            }
+            Ok(val) => (val,).into_lua_multi(lua),
+            Err(err) => (Nil, err).into_lua_multi(lua),
         }
+    }
 
-        Ok(result)
+    #[inline]
+    unsafe fn push_into_stack_multi(self, lua: &RawLua) -> Result<c_int> {
+        match self {
+            Ok(val) => (val,).push_into_stack_multi(lua),
+            Err(err) => (Nil, err).push_into_stack_multi(lua),
+        }
     }
 }
 
-impl<'lua, T: ToLua<'lua>> ToLuaMulti<'lua> for T {
-    fn to_lua_multi(self, lua: &'lua Lua) -> Result<MultiValue<'lua>> {
-        let mut v = MultiValue::new();
-        v.push_front(self.to_lua(lua)?);
+impl<E: IntoLua> IntoLuaMulti for StdResult<(), E> {
+    #[inline]
+    fn into_lua_multi(self, lua: &Lua) -> Result<MultiValue> {
+        match self {
+            Ok(_) => const { Ok(MultiValue::new()) },
+            Err(err) => (Nil, err).into_lua_multi(lua),
+        }
+    }
+
+    #[inline]
+    unsafe fn push_into_stack_multi(self, lua: &RawLua) -> Result<c_int> {
+        match self {
+            Ok(_) => Ok(0),
+            Err(err) => (Nil, err).push_into_stack_multi(lua),
+        }
+    }
+}
+
+impl<T: IntoLua> IntoLuaMulti for T {
+    #[inline]
+    fn into_lua_multi(self, lua: &Lua) -> Result<MultiValue> {
+        let mut v = MultiValue::with_capacity(1);
+        v.push_back(self.into_lua(lua)?);
         Ok(v)
     }
-}
 
-impl<'lua, T: FromLua<'lua>> FromLuaMulti<'lua> for T {
-    fn from_lua_multi(mut values: MultiValue<'lua>, lua: &'lua Lua) -> Result<Self> {
-        Ok(T::from_lua(values.pop_front().unwrap_or(Nil), lua)?)
+    #[inline]
+    unsafe fn push_into_stack_multi(self, lua: &RawLua) -> Result<c_int> {
+        self.push_into_stack(lua)?;
+        Ok(1)
     }
 }
 
-impl<'lua> ToLuaMulti<'lua> for MultiValue<'lua> {
-    fn to_lua_multi(self, _: &'lua Lua) -> Result<MultiValue<'lua>> {
+impl<T: FromLua> FromLuaMulti for T {
+    #[inline]
+    fn from_lua_multi(mut values: MultiValue, lua: &Lua) -> Result<Self> {
+        T::from_lua(values.pop_front().unwrap_or(Nil), lua)
+    }
+
+    #[inline]
+    fn from_lua_args(mut args: MultiValue, i: usize, to: Option<&str>, lua: &Lua) -> Result<Self> {
+        T::from_lua_arg(args.pop_front().unwrap_or(Nil), i, to, lua)
+    }
+
+    #[inline]
+    unsafe fn from_stack_multi(nvals: c_int, lua: &RawLua) -> Result<Self> {
+        if nvals == 0 {
+            return T::from_lua(Nil, lua.lua());
+        }
+        T::from_stack(-nvals, lua)
+    }
+
+    #[inline]
+    unsafe fn from_stack_args(nargs: c_int, i: usize, to: Option<&str>, lua: &RawLua) -> Result<Self> {
+        if nargs == 0 {
+            return T::from_lua_arg(Nil, i, to, lua.lua());
+        }
+        T::from_stack_arg(-nargs, i, to, lua)
+    }
+}
+
+/// Multiple Lua values used for both argument passing and also for multiple return values.
+#[derive(Default, Debug, Clone)]
+pub struct MultiValue(VecDeque<Value>);
+
+impl Deref for MultiValue {
+    type Target = VecDeque<Value>;
+
+    #[inline]
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}
+
+impl DerefMut for MultiValue {
+    #[inline]
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        &mut self.0
+    }
+}
+
+impl MultiValue {
+    /// Creates an empty `MultiValue` containing no values.
+    #[inline]
+    pub const fn new() -> MultiValue {
+        MultiValue(VecDeque::new())
+    }
+
+    /// Creates an empty `MultiValue` container with space for at least `capacity` elements.
+    pub fn with_capacity(capacity: usize) -> MultiValue {
+        MultiValue(VecDeque::with_capacity(capacity))
+    }
+
+    /// Creates a `MultiValue` container from vector of values.
+    ///
+    /// This method works in *O*(1) time and does not allocate any additional memory.
+    #[inline]
+    pub fn from_vec(vec: Vec<Value>) -> MultiValue {
+        vec.into()
+    }
+
+    /// Consumes the `MultiValue` and returns a vector of values.
+    ///
+    /// This method needs *O*(*n*) data movement if the circular buffer doesn't happen to be at the
+    /// beginning of the allocation.
+    #[inline]
+    pub fn into_vec(self) -> Vec<Value> {
+        self.into()
+    }
+
+    #[inline]
+    pub(crate) fn from_lua_iter<T: IntoLua>(lua: &Lua, iter: impl IntoIterator<Item = T>) -> Result<Self> {
+        let iter = iter.into_iter();
+        let mut multi_value = MultiValue::with_capacity(iter.size_hint().0);
+        for value in iter {
+            multi_value.push_back(value.into_lua(lua)?);
+        }
+        Ok(multi_value)
+    }
+}
+
+impl From<Vec<Value>> for MultiValue {
+    #[inline]
+    fn from(value: Vec<Value>) -> Self {
+        MultiValue(value.into())
+    }
+}
+
+impl From<MultiValue> for Vec<Value> {
+    #[inline]
+    fn from(value: MultiValue) -> Self {
+        value.0.into()
+    }
+}
+
+impl FromIterator<Value> for MultiValue {
+    #[inline]
+    fn from_iter<I: IntoIterator<Item = Value>>(iter: I) -> Self {
+        let mut multi_value = MultiValue::new();
+        multi_value.extend(iter);
+        multi_value
+    }
+}
+
+impl IntoIterator for MultiValue {
+    type Item = Value;
+    type IntoIter = vec_deque::IntoIter<Value>;
+
+    #[inline]
+    fn into_iter(mut self) -> Self::IntoIter {
+        let deque = mem::take(&mut self.0);
+        mem::forget(self);
+        deque.into_iter()
+    }
+}
+
+impl<'a> IntoIterator for &'a MultiValue {
+    type Item = &'a Value;
+    type IntoIter = vec_deque::Iter<'a, Value>;
+
+    #[inline]
+    fn into_iter(self) -> Self::IntoIter {
+        self.0.iter()
+    }
+}
+
+impl IntoLuaMulti for MultiValue {
+    #[inline]
+    fn into_lua_multi(self, _: &Lua) -> Result<MultiValue> {
         Ok(self)
     }
 }
 
-impl<'lua> FromLuaMulti<'lua> for MultiValue<'lua> {
-    fn from_lua_multi(values: MultiValue<'lua>, _: &'lua Lua) -> Result<Self> {
+impl FromLuaMulti for MultiValue {
+    #[inline]
+    fn from_lua_multi(values: MultiValue, _: &Lua) -> Result<Self> {
         Ok(values)
     }
 }
@@ -73,22 +234,46 @@ impl<'lua> FromLuaMulti<'lua> for MultiValue<'lua> {
 /// # Ok(())
 /// # }
 /// ```
-///
-/// [`FromLua`]: trait.FromLua.html
-/// [`MultiValue`]: struct.MultiValue.html
-#[derive(Debug, Clone)]
+#[derive(Default, Debug, Clone)]
 pub struct Variadic<T>(Vec<T>);
 
 impl<T> Variadic<T> {
     /// Creates an empty `Variadic` wrapper containing no values.
-    pub fn new() -> Variadic<T> {
+    pub const fn new() -> Variadic<T> {
         Variadic(Vec::new())
     }
+
+    /// Creates an empty `Variadic` container with space for at least `capacity` elements.
+    pub fn with_capacity(capacity: usize) -> Variadic<T> {
+        Variadic(Vec::with_capacity(capacity))
+    }
 }
 
-impl<T> Default for Variadic<T> {
-    fn default() -> Variadic<T> {
-        Variadic::new()
+impl<T> Deref for Variadic<T> {
+    type Target = Vec<T>;
+
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}
+
+impl<T> DerefMut for Variadic<T> {
+    fn deref_mut(&mut self) -> &mut Self::Target {
+        &mut self.0
+    }
+}
+
+impl<T> From<Vec<T>> for Variadic<T> {
+    #[inline]
+    fn from(vec: Vec<T>) -> Self {
+        Variadic(vec)
+    }
+}
+
+impl<T> From<Variadic<T>> for Vec<T> {
+    #[inline]
+    fn from(value: Variadic<T>) -> Self {
+        value.0
     }
 }
 
@@ -107,31 +292,28 @@ impl<T> IntoIterator for Variadic<T> {
     }
 }
 
-impl<T> Deref for Variadic<T> {
-    type Target = Vec<T>;
+impl<T: IntoLua> IntoLuaMulti for Variadic<T> {
+    #[inline]
+    fn into_lua_multi(self, lua: &Lua) -> Result<MultiValue> {
+        MultiValue::from_lua_iter(lua, self)
+    }
 
-    fn deref(&self) -> &Self::Target {
-        &self.0
+    unsafe fn push_into_stack_multi(self, lua: &RawLua) -> Result<c_int> {
+        let nresults = self.len() as i32;
+        check_stack(lua.state(), nresults + 1)?;
+        for value in self.0 {
+            value.push_into_stack(lua)?;
+        }
+        Ok(nresults)
     }
 }
 
-impl<T> DerefMut for Variadic<T> {
-    fn deref_mut(&mut self) -> &mut Self::Target {
-        &mut self.0
-    }
-}
-
-impl<'lua, T: ToLua<'lua>> ToLuaMulti<'lua> for Variadic<T> {
-    fn to_lua_multi(self, lua: &'lua Lua) -> Result<MultiValue<'lua>> {
-        self.0.into_iter().map(|e| e.to_lua(lua)).collect()
-    }
-}
-
-impl<'lua, T: FromLua<'lua>> FromLuaMulti<'lua> for Variadic<T> {
-    fn from_lua_multi(values: MultiValue<'lua>, lua: &'lua Lua) -> Result<Self> {
+impl<T: FromLua> FromLuaMulti for Variadic<T> {
+    #[inline]
+    fn from_lua_multi(mut values: MultiValue, lua: &Lua) -> Result<Self> {
         values
-            .into_iter()
-            .map(|e| T::from_lua(e, lua))
+            .drain(..)
+            .map(|val| T::from_lua(val, lua))
             .collect::<Result<Vec<T>>>()
             .map(Variadic)
     }
@@ -139,45 +321,116 @@ impl<'lua, T: FromLua<'lua>> FromLuaMulti<'lua> for Variadic<T> {
 
 macro_rules! impl_tuple {
     () => (
-        impl<'lua> ToLuaMulti<'lua> for () {
-            fn to_lua_multi(self, _: &'lua Lua) -> Result<MultiValue<'lua>> {
-                Ok(MultiValue::new())
+        impl IntoLuaMulti for () {
+            #[inline]
+            fn into_lua_multi(self, _: &Lua) -> Result<MultiValue> {
+                const { Ok(MultiValue::new()) }
+            }
+
+            #[inline]
+            unsafe fn push_into_stack_multi(self, _lua: &RawLua) -> Result<c_int> {
+                Ok(0)
             }
         }
 
-        impl<'lua> FromLuaMulti<'lua> for () {
-            fn from_lua_multi(_: MultiValue, _: &'lua Lua) -> Result<Self> {
+        impl FromLuaMulti for () {
+            #[inline]
+            fn from_lua_multi(_values: MultiValue, _lua: &Lua) -> Result<Self> {
+                Ok(())
+            }
+
+            #[inline]
+            unsafe fn from_stack_multi(_nvals: c_int, _lua: &RawLua) -> Result<Self> {
                 Ok(())
             }
         }
     );
 
     ($last:ident $($name:ident)*) => (
-        impl<'lua, $($name,)* $last> ToLuaMulti<'lua> for ($($name,)* $last,)
-            where $($name: ToLua<'lua>,)*
-                  $last: ToLuaMulti<'lua>
+        impl<$($name,)* $last> IntoLuaMulti for ($($name,)* $last,)
+            where $($name: IntoLua,)*
+                  $last: IntoLuaMulti
         {
-            #[allow(unused_mut)]
-            #[allow(non_snake_case)]
-            fn to_lua_multi(self, lua: &'lua Lua) -> Result<MultiValue<'lua>> {
+            #[allow(unused_mut, non_snake_case)]
+            #[inline]
+            fn into_lua_multi(self, lua: &Lua) -> Result<MultiValue> {
                 let ($($name,)* $last,) = self;
 
-                let mut results = $last.to_lua_multi(lua)?;
-                push_reverse!(results, $($name.to_lua(lua)?,)*);
+                let mut results = $last.into_lua_multi(lua)?;
+                push_reverse!(results, $($name.into_lua(lua)?,)*);
                 Ok(results)
             }
+
+            #[allow(non_snake_case)]
+            #[inline]
+            unsafe fn push_into_stack_multi(self, lua: &RawLua) -> Result<c_int> {
+                let ($($name,)* $last,) = self;
+                let mut nresults = 0;
+                $(
+                    _ = $name;
+                    nresults += 1;
+                )*
+                check_stack(lua.state(), nresults + 1)?;
+                $(
+                    $name.push_into_stack(lua)?;
+                )*
+                nresults += $last.push_into_stack_multi(lua)?;
+                Ok(nresults)
+            }
         }
 
-        impl<'lua, $($name,)* $last> FromLuaMulti<'lua> for ($($name,)* $last,)
-            where $($name: FromLua<'lua>,)*
-                  $last: FromLuaMulti<'lua>
+        impl<$($name,)* $last> FromLuaMulti for ($($name,)* $last,)
+            where $($name: FromLua,)*
+                  $last: FromLuaMulti
         {
-            #[allow(unused_mut)]
-            #[allow(non_snake_case)]
-            fn from_lua_multi(mut values: MultiValue<'lua>, lua: &'lua Lua) -> Result<Self> {
-                $(let $name = values.pop_front().unwrap_or(Nil);)*
+            #[allow(unused_mut, non_snake_case)]
+            #[inline]
+            fn from_lua_multi(mut values: MultiValue, lua: &Lua) -> Result<Self> {
+                $(let $name = FromLua::from_lua(values.pop_front().unwrap_or(Nil), lua)?;)*
                 let $last = FromLuaMulti::from_lua_multi(values, lua)?;
-                Ok(($(FromLua::from_lua($name, lua)?,)* $last,))
+                Ok(($($name,)* $last,))
+            }
+
+            #[allow(unused_mut, non_snake_case)]
+            #[inline]
+            fn from_lua_args(mut args: MultiValue, mut i: usize, to: Option<&str>, lua: &Lua) -> Result<Self> {
+                $(
+                    let $name = FromLua::from_lua_arg(args.pop_front().unwrap_or(Nil), i, to, lua)?;
+                    i += 1;
+                )*
+                let $last = FromLuaMulti::from_lua_args(args, i, to, lua)?;
+                Ok(($($name,)* $last,))
+            }
+
+            #[allow(unused_mut, non_snake_case)]
+            #[inline]
+            unsafe fn from_stack_multi(mut nvals: c_int, lua: &RawLua) -> Result<Self> {
+                $(
+                    let $name = if nvals > 0 {
+                        nvals -= 1;
+                        FromLua::from_stack(-(nvals + 1), lua)
+                    } else {
+                        FromLua::from_lua(Nil, lua.lua())
+                    }?;
+                )*
+                let $last = FromLuaMulti::from_stack_multi(nvals, lua)?;
+                Ok(($($name,)* $last,))
+            }
+
+            #[allow(unused_mut, non_snake_case)]
+            #[inline]
+            unsafe fn from_stack_args(mut nargs: c_int, mut i: usize, to: Option<&str>, lua: &RawLua) -> Result<Self> {
+                $(
+                    let $name = if nargs > 0 {
+                        nargs -= 1;
+                        FromLua::from_stack_arg(-(nargs + 1), i, to, lua)
+                    } else {
+                        FromLua::from_lua_arg(Nil, i, to, lua.lua())
+                    }?;
+                    i += 1;
+                )*
+                let $last = FromLuaMulti::from_stack_args(nargs, i, to, lua)?;
+                Ok(($($name,)* $last,))
             }
         }
     );
@@ -213,3 +466,13 @@ impl_tuple!(A B C D E F G H I J K L M);
 impl_tuple!(A B C D E F G H I J K L M N);
 impl_tuple!(A B C D E F G H I J K L M N O);
 impl_tuple!(A B C D E F G H I J K L M N O P);
+
+#[cfg(test)]
+mod assertions {
+    use super::*;
+
+    #[cfg(not(feature = "send"))]
+    static_assertions::assert_not_impl_any!(MultiValue: Send);
+    #[cfg(feature = "send")]
+    static_assertions::assert_impl_all!(MultiValue: Send, Sync);
+}

src/prelude.rs

@@ -1,12 +1,40 @@
 //! Re-exports most types with an extra `Lua*` prefix to prevent name clashes.
 
+#[doc(no_inline)]
 pub use crate::{
-    AnyUserData as LuaAnyUserData, Chunk as LuaChunk, Error as LuaError,
+    AnyUserData as LuaAnyUserData, BorrowedBytes as LuaBorrowedBytes, BorrowedStr as LuaBorrowedStr,
+    Chunk as LuaChunk, Either as LuaEither, Error as LuaError, ErrorContext as LuaErrorContext,
     ExternalError as LuaExternalError, ExternalResult as LuaExternalResult, FromLua, FromLuaMulti,
-    Function as LuaFunction, Integer as LuaInteger, LightUserData as LuaLightUserData, Lua,
+    Function as LuaFunction, FunctionInfo as LuaFunctionInfo, GCMode as LuaGCMode, Integer as LuaInteger,
+    IntoLua, IntoLuaMulti, LightUserData as LuaLightUserData, Lua, LuaNativeFn, LuaNativeFnMut, LuaOptions,
     MetaMethod as LuaMetaMethod, MultiValue as LuaMultiValue, Nil as LuaNil, Number as LuaNumber,
-    RegistryKey as LuaRegistryKey, Result as LuaResult, Scope as LuaScope, String as LuaString,
-    Table as LuaTable, TablePairs as LuaTablePairs, TableSequence as LuaTableSequence,
-    Thread as LuaThread, ThreadStatus as LuaThreadStatus, ToLua, ToLuaMulti,
-    UserData as LuaUserData, UserDataMethods as LuaUserDataMethods, Value as LuaValue,
+    ObjectLike as LuaObjectLike, RegistryKey as LuaRegistryKey, Result as LuaResult, StdLib as LuaStdLib,
+    String as LuaString, Table as LuaTable, TablePairs as LuaTablePairs, TableSequence as LuaTableSequence,
+    Thread as LuaThread, ThreadStatus as LuaThreadStatus, UserData as LuaUserData,
+    UserDataFields as LuaUserDataFields, UserDataMetatable as LuaUserDataMetatable,
+    UserDataMethods as LuaUserDataMethods, UserDataRef as LuaUserDataRef,
+    UserDataRefMut as LuaUserDataRefMut, UserDataRegistry as LuaUserDataRegistry, Value as LuaValue,
+    Variadic as LuaVariadic, VmState as LuaVmState, WeakLua,
+};
+
+#[cfg(not(feature = "luau"))]
+#[doc(no_inline)]
+pub use crate::HookTriggers as LuaHookTriggers;
+
+#[cfg(feature = "luau")]
+#[doc(no_inline)]
+pub use crate::{
+    CompileConstant as LuaCompileConstant, CoverageInfo as LuaCoverageInfo,
+    NavigateError as LuaNavigateError, Require as LuaRequire, TextRequirer as LuaTextRequirer,
+    Vector as LuaVector,
+};
+
+#[cfg(feature = "async")]
+#[doc(no_inline)]
+pub use crate::{AsyncThread as LuaAsyncThread, LuaNativeAsyncFn};
+
+#[cfg(feature = "serde")]
+#[doc(no_inline)]
+pub use crate::{
+    DeserializeOptions as LuaDeserializeOptions, LuaSerdeExt, SerializeOptions as LuaSerializeOptions,
 };

src/scope.rs

@@ -1,69 +1,60 @@
-use std::any::Any;
-use std::cell::Cell;
 use std::cell::RefCell;
 use std::marker::PhantomData;
 use std::mem;
-use std::os::raw::c_void;
-use std::rc::Rc;
 
 use crate::error::{Error, Result};
-use crate::ffi;
 use crate::function::Function;
-use crate::lua::Lua;
-use crate::types::{Callback, LuaRef};
-use crate::userdata::{AnyUserData, MetaMethod, UserData, UserDataMethods};
-use crate::util::{
-    assert_stack, init_userdata_metatable, protect_lua_closure, push_string, push_userdata,
-    take_userdata, StackGuard,
-};
-use crate::value::{FromLuaMulti, MultiValue, ToLuaMulti, Value};
+use crate::state::{Lua, LuaGuard, RawLua};
+use crate::traits::{FromLuaMulti, IntoLuaMulti};
+use crate::types::{Callback, CallbackUpvalue, ScopedCallback, ValueRef};
+use crate::userdata::{AnyUserData, UserData, UserDataRegistry, UserDataStorage};
+use crate::util::{self, check_stack, get_metatable_ptr, get_userdata, take_userdata, StackGuard};
 
 /// Constructed by the [`Lua::scope`] method, allows temporarily creating Lua userdata and
-/// callbacks that are not required to be Send or 'static.
+/// callbacks that are not required to be `Send` or `'static`.
 ///
 /// See [`Lua::scope`] for more details.
-///
-/// [`Lua::scope`]: struct.Lua.html#method.scope
-pub struct Scope<'lua, 'scope> {
-    lua: &'lua Lua,
-    destructors: RefCell<Vec<(LuaRef<'lua>, fn(LuaRef<'lua>) -> Box<dyn Any>)>>,
-    _scope_invariant: PhantomData<Cell<&'scope ()>>,
+pub struct Scope<'scope, 'env: 'scope> {
+    lua: LuaGuard,
+    // Internal destructors run first, then user destructors (based on the declaration order)
+    destructors: Destructors<'env>,
+    user_destructors: UserDestructors<'env>,
+    _scope_invariant: PhantomData<&'scope mut &'scope ()>,
+    _env_invariant: PhantomData<&'env mut &'env ()>,
 }
 
-impl<'lua, 'scope> Scope<'lua, 'scope> {
-    pub(crate) fn new(lua: &'lua Lua) -> Scope<'lua, 'scope> {
+type DestructorCallback<'a> = Box<dyn FnOnce(&RawLua, ValueRef) -> Vec<Box<dyn FnOnce() + 'a>>>;
+
+// Implement Drop on Destructors instead of Scope to avoid compilation error
+struct Destructors<'a>(RefCell<Vec<(ValueRef, DestructorCallback<'a>)>>);
+
+struct UserDestructors<'a>(RefCell<Vec<Box<dyn FnOnce() + 'a>>>);
+
+impl<'scope, 'env: 'scope> Scope<'scope, 'env> {
+    pub(crate) fn new(lua: LuaGuard) -> Self {
         Scope {
             lua,
-            destructors: RefCell::new(Vec::new()),
+            destructors: Destructors(RefCell::new(Vec::new())),
+            user_destructors: UserDestructors(RefCell::new(Vec::new())),
             _scope_invariant: PhantomData,
+            _env_invariant: PhantomData,
         }
     }
 
     /// Wraps a Rust function or closure, creating a callable Lua function handle to it.
     ///
     /// This is a version of [`Lua::create_function`] that creates a callback which expires on
-    /// scope drop.  See [`Lua::scope`] for more details.
-    ///
-    /// [`Lua::create_function`]: struct.Lua.html#method.create_function
-    /// [`Lua::scope`]: struct.Lua.html#method.scope
-    pub fn create_function<'callback, A, R, F>(&'callback self, func: F) -> Result<Function<'lua>>
+    /// scope drop. See [`Lua::scope`] for more details.
+    pub fn create_function<F, A, R>(&'scope self, func: F) -> Result<Function>
     where
-        A: FromLuaMulti<'callback>,
-        R: ToLuaMulti<'callback>,
-        F: 'scope + Fn(&'callback Lua, A) -> Result<R>,
+        F: Fn(&Lua, A) -> Result<R> + 'scope,
+        A: FromLuaMulti,
+        R: IntoLuaMulti,
     {
-        // Safe, because 'scope must outlive 'callback (due to Self containing 'scope), however the
-        // callback itself must be 'scope lifetime, so the function should not be able to capture
-        // anything of 'callback lifetime.  'scope can't be shortened due to being invariant, and
-        // the 'callback lifetime here can't be enlarged due to coming from a universal
-        // quantification in Lua::scope.
-        //
-        // I hope I got this explanation right, but in any case this is tested with compiletest_rs
-        // to make sure callbacks can't capture handles with lifetime outside the scope, inside the
-        // scope, and owned inside the callback itself.
         unsafe {
-            self.create_callback(Box::new(move |lua, args| {
-                func(lua, A::from_lua_multi(args, lua)?)?.to_lua_multi(lua)
+            self.create_callback(Box::new(move |rawlua, nargs| {
+                let args = A::from_stack_args(nargs, 1, None, rawlua)?;
+                func(rawlua.lua(), args)?.push_into_stack_multi(rawlua)
             }))
         }
     }
@@ -71,414 +62,268 @@ impl<'lua, 'scope> Scope<'lua, 'scope> {
     /// Wraps a Rust mutable closure, creating a callable Lua function handle to it.
     ///
     /// This is a version of [`Lua::create_function_mut`] that creates a callback which expires
-    /// on scope drop.  See [`Lua::scope`] and [`Scope::create_function`] for more details.
-    ///
-    /// [`Lua::create_function_mut`]: struct.Lua.html#method.create_function_mut
-    /// [`Lua::scope`]: struct.Lua.html#method.scope
-    /// [`Scope::create_function`]: #method.create_function
-    pub fn create_function_mut<'callback, A, R, F>(
-        &'callback self,
-        func: F,
-    ) -> Result<Function<'lua>>
+    /// on scope drop. See [`Lua::scope`] and [`Scope::create_function`] for more details.
+    pub fn create_function_mut<F, A, R>(&'scope self, func: F) -> Result<Function>
     where
-        A: FromLuaMulti<'callback>,
-        R: ToLuaMulti<'callback>,
-        F: 'scope + FnMut(&'callback Lua, A) -> Result<R>,
+        F: FnMut(&Lua, A) -> Result<R> + 'scope,
+        A: FromLuaMulti,
+        R: IntoLuaMulti,
     {
         let func = RefCell::new(func);
         self.create_function(move |lua, args| {
-            (&mut *func
-                .try_borrow_mut()
-                .map_err(|_| Error::RecursiveMutCallback)?)(lua, args)
+            (*func.try_borrow_mut().map_err(|_| Error::RecursiveMutCallback)?)(lua, args)
         })
     }
 
-    /// Create a Lua userdata object from a custom userdata type.
+    /// Creates a Lua userdata object from a reference to custom userdata type.
     ///
     /// This is a version of [`Lua::create_userdata`] that creates a userdata which expires on
-    /// scope drop, and does not require that the userdata type be Send (but still requires that the
-    /// UserData be 'static).  See [`Lua::scope`] for more details.
+    /// scope drop, and does not require that the userdata type be Send. This method takes
+    /// non-'static reference to the data. See [`Lua::scope`] for more details.
     ///
-    /// [`Lua::create_userdata`]: struct.Lua.html#method.create_userdata
-    /// [`Lua::scope`]: struct.Lua.html#method.scope
-    pub fn create_static_userdata<T>(&self, data: T) -> Result<AnyUserData<'lua>>
+    /// Userdata created with this method will not be able to be mutated from Lua.
+    pub fn create_userdata_ref<T>(&'scope self, data: &'env T) -> Result<AnyUserData>
     where
-        T: 'static + UserData,
+        T: UserData + 'static,
     {
-        // Safe even though T may not be Send, because the parent Lua cannot be sent to another
-        // thread while the Scope is alive (or the returned AnyUserData handle even).
-        unsafe {
-            let u = self.lua.make_userdata(data)?;
-            self.destructors.borrow_mut().push((u.0.clone(), |u| {
-                let state = u.lua.state;
-                assert_stack(state, 2);
-                u.lua.push_ref(&u);
-                // We know the destructor has not run yet because we hold a reference to the
-                // userdata.
-                Box::new(take_userdata::<RefCell<T>>(state))
-            }));
-            Ok(u)
-        }
+        let ud = unsafe { self.lua.make_userdata(UserDataStorage::new_ref(data)) }?;
+        self.seal_userdata::<T>(&ud);
+        Ok(ud)
     }
 
-    /// Create a Lua userdata object from a custom userdata type.
+    /// Creates a Lua userdata object from a mutable reference to custom userdata type.
     ///
     /// This is a version of [`Lua::create_userdata`] that creates a userdata which expires on
-    /// scope drop, and does not require that the userdata type be Send or 'static. See
+    /// scope drop, and does not require that the userdata type be Send. This method takes
+    /// non-'static mutable reference to the data. See [`Lua::scope`] for more details.
+    pub fn create_userdata_ref_mut<T>(&'scope self, data: &'env mut T) -> Result<AnyUserData>
+    where
+        T: UserData + 'static,
+    {
+        let ud = unsafe { self.lua.make_userdata(UserDataStorage::new_ref_mut(data)) }?;
+        self.seal_userdata::<T>(&ud);
+        Ok(ud)
+    }
+
+    /// Creates a Lua userdata object from a reference to custom Rust type.
+    ///
+    /// This is a version of [`Lua::create_any_userdata`] that creates a userdata which expires on
+    /// scope drop, and does not require that the Rust type be Send. This method takes non-'static
+    /// reference to the data. See [`Lua::scope`] for more details.
+    ///
+    /// Userdata created with this method will not be able to be mutated from Lua.
+    pub fn create_any_userdata_ref<T>(&'scope self, data: &'env T) -> Result<AnyUserData>
+    where
+        T: 'static,
+    {
+        let ud = unsafe { self.lua.make_any_userdata(UserDataStorage::new_ref(data)) }?;
+        self.seal_userdata::<T>(&ud);
+        Ok(ud)
+    }
+
+    /// Creates a Lua userdata object from a mutable reference to custom Rust type.
+    ///
+    /// This is a version of [`Lua::create_any_userdata`] that creates a userdata which expires on
+    /// scope drop, and does not require that the Rust type be Send. This method takes non-'static
+    /// mutable reference to the data. See [`Lua::scope`] for more details.
+    pub fn create_any_userdata_ref_mut<T>(&'scope self, data: &'env mut T) -> Result<AnyUserData>
+    where
+        T: 'static,
+    {
+        let ud = unsafe { self.lua.make_any_userdata(UserDataStorage::new_ref_mut(data)) }?;
+        self.seal_userdata::<T>(&ud);
+        Ok(ud)
+    }
+
+    /// Creates a Lua userdata object from a custom userdata type.
+    ///
+    /// This is a version of [`Lua::create_userdata`] that creates a userdata which expires on
+    /// scope drop, and does not require that the userdata type be `Send` or `'static`. See
     /// [`Lua::scope`] for more details.
     ///
-    /// Lifting the requirement that the UserData type be 'static comes with some important
-    /// limitations, so if you only need to eliminate the Send requirement, it is probably better to
-    /// use [`Scope::create_static_userdata`] instead.
-    ///
     /// The main limitation that comes from using non-'static userdata is that the produced userdata
-    /// will no longer have a `TypeId` associated with it, becuase `TypeId` can only work for
-    /// 'static types.  This means that it is impossible, once the userdata is created, to get a
-    /// reference to it back *out* of an `AnyUserData` handle.  This also implies that the
+    /// will no longer have a [`TypeId`] associated with it, because [`TypeId`] can only work for
+    /// `'static` types. This means that it is impossible, once the userdata is created, to get a
+    /// reference to it back *out* of an [`AnyUserData`] handle. This also implies that the
     /// "function" type methods that can be added via [`UserDataMethods`] (the ones that accept
-    /// `AnyUserData` as a first parameter) are vastly less useful.  Also, there is no way to re-use
-    /// a single metatable for multiple non-'static types, so there is a higher cost associated with
-    /// creating the userdata metatable each time a new userdata is created.
+    /// [`AnyUserData`] as a first parameter) are vastly less useful. Also, there is no way to
+    /// re-use a single metatable for multiple non-'static types, so there is a higher cost
+    /// associated with creating the userdata metatable each time a new userdata is created.
     ///
-    /// [`create_static_userdata`]: #method.create_static_userdata
-    /// [`Lua::create_userdata`]: struct.Lua.html#method.create_userdata
-    /// [`Lua::scope`]: struct.Lua.html#method.scope
-    /// [`UserDataMethods`]: trait.UserDataMethods.html
-    pub fn create_nonstatic_userdata<T>(&self, data: T) -> Result<AnyUserData<'lua>>
+    /// [`TypeId`]: std::any::TypeId
+    /// [`UserDataMethods`]: crate::UserDataMethods
+    pub fn create_userdata<T>(&'scope self, data: T) -> Result<AnyUserData>
     where
-        T: 'scope + UserData,
+        T: UserData + 'env,
     {
-        let data = Rc::new(RefCell::new(data));
-
-        // 'callback outliving 'scope is a lie to make the types work out, required due to the
-        // inability to work with the more correct callback type that is universally quantified over
-        // 'lua.  This is safe though, because `UserData::add_methods` does not get to pick the 'lua
-        // lifetime, so none of the static methods UserData types can add can possibly capture
-        // parameters.
-        fn wrap_method<'scope, 'lua, 'callback: 'scope, T: 'scope>(
-            scope: &Scope<'lua, 'scope>,
-            data: Rc<RefCell<T>>,
-            method: NonStaticMethod<'callback, T>,
-        ) -> Result<Function<'lua>> {
-            // On methods that actually receive the userdata, we fake a type check on the passed in
-            // userdata, where we pretend there is a unique type per call to
-            // `Scope::create_nonstatic_userdata`.  You can grab a method from a userdata and call
-            // it on a mismatched userdata type, which when using normal 'static userdata will fail
-            // with a type mismatch, but here without this check would proceed as though you had
-            // called the method on the original value (since we otherwise completely ignore the
-            // first argument).
-            let check_data = data.clone();
-            let check_ud_type = move |lua: &'callback Lua, value| {
-                if let Some(value) = value {
-                    if let Value::UserData(u) = value {
-                        unsafe {
-                            assert_stack(lua.state, 1);
-                            lua.push_ref(&u.0);
-                            ffi::lua_getuservalue(lua.state, -1);
-                            #[cfg(any(feature = "lua52", feature = "lua51", feature = "luajit"))]
-                            {
-                                ffi::lua_pushinteger(lua.state, 1);
-                                ffi::lua_gettable(lua.state, -2);
-                                ffi::lua_remove(lua.state, -2);
-                            }
-                            return ffi::lua_touserdata(lua.state, -1)
-                                == check_data.as_ptr() as *mut c_void;
-                        }
-                    }
-                }
-
-                false
-            };
-
-            match method {
-                NonStaticMethod::Method(method) => {
-                    let method_data = data.clone();
-                    let f = Box::new(move |lua, mut args: MultiValue<'callback>| {
-                        if !check_ud_type(lua, args.pop_front()) {
-                            return Err(Error::UserDataTypeMismatch);
-                        }
-                        let data = method_data
-                            .try_borrow()
-                            .map_err(|_| Error::UserDataBorrowError)?;
-                        method(lua, &*data, args)
-                    });
-                    unsafe { scope.create_callback(f) }
-                }
-                NonStaticMethod::MethodMut(method) => {
-                    let method = RefCell::new(method);
-                    let method_data = data.clone();
-                    let f = Box::new(move |lua, mut args: MultiValue<'callback>| {
-                        if !check_ud_type(lua, args.pop_front()) {
-                            return Err(Error::UserDataTypeMismatch);
-                        }
-                        let mut method = method
-                            .try_borrow_mut()
-                            .map_err(|_| Error::RecursiveMutCallback)?;
-                        let mut data = method_data
-                            .try_borrow_mut()
-                            .map_err(|_| Error::UserDataBorrowMutError)?;
-                        (&mut *method)(lua, &mut *data, args)
-                    });
-                    unsafe { scope.create_callback(f) }
-                }
-                NonStaticMethod::Function(function) => unsafe { scope.create_callback(function) },
-                NonStaticMethod::FunctionMut(function) => {
-                    let function = RefCell::new(function);
-                    let f = Box::new(move |lua, args| {
-                        (&mut *function
-                            .try_borrow_mut()
-                            .map_err(|_| Error::RecursiveMutCallback)?)(
-                            lua, args
-                        )
-                    });
-                    unsafe { scope.create_callback(f) }
-                }
-            }
-        }
-
-        let mut ud_methods = NonStaticUserDataMethods::default();
-        T::add_methods(&mut ud_methods);
-
+        let state = self.lua.state();
         unsafe {
-            let lua = self.lua;
-            let _sg = StackGuard::new(lua.state);
-            assert_stack(lua.state, 6);
+            let _sg = StackGuard::new(state);
+            check_stack(state, 3)?;
 
-            push_userdata(lua.state, ())?;
-            #[cfg(feature = "lua53")]
-            ffi::lua_pushlightuserdata(lua.state, data.as_ptr() as *mut c_void);
-            #[cfg(any(feature = "lua52", feature = "lua51", feature = "luajit"))]
-            protect_lua_closure(lua.state, 0, 1, |state| {
-                // Lua 5.2/5.1 allows to store only table. Then we will wrap the value.
-                ffi::lua_createtable(state, 1, 0);
-                ffi::lua_pushinteger(state, 1);
-                ffi::lua_pushlightuserdata(state, data.as_ptr() as *mut c_void);
-                ffi::lua_settable(state, -3);
-            })?;
-            ffi::lua_setuservalue(lua.state, -2);
+            // We don't write the data to the userdata until pushing the metatable
+            let protect = !self.lua.unlikely_memory_error();
+            #[cfg(feature = "luau")]
+            let ud_ptr = {
+                let data = UserDataStorage::new_scoped(data);
+                util::push_userdata(state, data, protect)?
+            };
+            #[cfg(not(feature = "luau"))]
+            let ud_ptr = util::push_uninit_userdata::<UserDataStorage<T>>(state, protect)?;
 
-            protect_lua_closure(lua.state, 0, 1, move |state| {
-                ffi::lua_newtable(state);
-            })?;
+            // Push the metatable and register it with no TypeId
+            let mut registry = UserDataRegistry::new_unique(self.lua.lua(), ud_ptr as *mut _);
+            T::register(&mut registry);
+            self.lua.push_userdata_metatable(registry.into_raw())?;
+            let mt_ptr = ffi::lua_topointer(state, -1);
+            self.lua.register_userdata_metatable(mt_ptr, None);
 
-            for (k, m) in ud_methods.meta_methods {
-                push_string(lua.state, k.name())?;
-                lua.push_value(Value::Function(wrap_method(self, data.clone(), m)?))?;
+            // Write data to the pointer and attach metatable
+            #[cfg(not(feature = "luau"))]
+            std::ptr::write(ud_ptr, UserDataStorage::new_scoped(data));
+            ffi::lua_setmetatable(state, -2);
 
-                protect_lua_closure(lua.state, 3, 1, |state| {
-                    ffi::lua_rawset(state, -3);
-                })?;
-            }
+            let ud = AnyUserData(self.lua.pop_ref());
+            self.seal_userdata::<T>(&ud);
 
-            if ud_methods.methods.is_empty() {
-                init_userdata_metatable::<()>(lua.state, -1, None)?;
-            } else {
-                protect_lua_closure(lua.state, 0, 1, |state| {
-                    ffi::lua_newtable(state);
-                })?;
-                for (k, m) in ud_methods.methods {
-                    push_string(lua.state, &k)?;
-                    lua.push_value(Value::Function(wrap_method(self, data.clone(), m)?))?;
-                    protect_lua_closure(lua.state, 3, 1, |state| {
-                        ffi::lua_rawset(state, -3);
-                    })?;
-                }
-
-                init_userdata_metatable::<()>(lua.state, -2, Some(-1))?;
-                ffi::lua_pop(lua.state, 1);
-            }
-
-            ffi::lua_setmetatable(lua.state, -2);
-
-            Ok(AnyUserData(lua.pop_ref()))
+            Ok(ud)
         }
     }
 
-    // Unsafe, because the callback can improperly capture any value with 'callback scope, such as
-    // improperly capturing an argument. Since the 'callback lifetime is chosen by the user and the
-    // lifetime of the callback itself is 'scope (non-'static), the borrow checker will happily pick
-    // a 'callback that outlives 'scope to allow this.  In order for this to be safe, the callback
-    // must NOT capture any parameters.
-    unsafe fn create_callback<'callback>(
-        &self,
-        f: Callback<'callback, 'scope>,
-    ) -> Result<Function<'lua>> {
-        let f = mem::transmute::<Callback<'callback, 'scope>, Callback<'lua, 'static>>(f);
+    /// Creates a Lua userdata object from a custom Rust type.
+    ///
+    /// Since the Rust type is not required to be static and implement [`UserData`] trait,
+    /// you need to provide a function to register fields or methods for the object.
+    ///
+    /// See also [`Scope::create_userdata`] for more details about non-static limitations.
+    pub fn create_any_userdata<T>(
+        &'scope self,
+        data: T,
+        register: impl FnOnce(&mut UserDataRegistry<T>),
+    ) -> Result<AnyUserData>
+    where
+        T: 'env,
+    {
+        let state = self.lua.state();
+        let ud = unsafe {
+            let _sg = StackGuard::new(state);
+            check_stack(state, 3)?;
+
+            // We don't write the data to the userdata until pushing the metatable
+            let protect = !self.lua.unlikely_memory_error();
+            #[cfg(feature = "luau")]
+            let ud_ptr = {
+                let data = UserDataStorage::new_scoped(data);
+                util::push_userdata(state, data, protect)?
+            };
+            #[cfg(not(feature = "luau"))]
+            let ud_ptr = util::push_uninit_userdata::<UserDataStorage<T>>(state, protect)?;
+
+            // Push the metatable and register it with no TypeId
+            let mut registry = UserDataRegistry::new_unique(self.lua.lua(), ud_ptr as *mut _);
+            register(&mut registry);
+            self.lua.push_userdata_metatable(registry.into_raw())?;
+            let mt_ptr = ffi::lua_topointer(state, -1);
+            self.lua.register_userdata_metatable(mt_ptr, None);
+
+            // Write data to the pointer and attach metatable
+            #[cfg(not(feature = "luau"))]
+            std::ptr::write(ud_ptr, UserDataStorage::new_scoped(data));
+            ffi::lua_setmetatable(state, -2);
+
+            AnyUserData(self.lua.pop_ref())
+        };
+        self.seal_userdata::<T>(&ud);
+        Ok(ud)
+    }
+
+    /// Adds a destructor function to be run when the scope ends.
+    ///
+    /// This functionality is useful for cleaning up any resources after the scope ends.
+    ///
+    /// # Example
+    ///
+    /// ```rust
+    /// # use mlua::{Error, Lua, Result};
+    /// # fn main() -> Result<()> {
+    /// let lua = Lua::new();
+    /// let ud = lua.create_any_userdata(String::from("hello"))?;
+    /// lua.scope(|scope| {
+    ///     scope.add_destructor(|| {
+    ///         _ = ud.take::<String>();
+    ///     });
+    ///     // Run the code that uses `ud` here
+    ///    Ok(())
+    /// })?;
+    /// assert!(matches!(ud.borrow::<String>(), Err(Error::UserDataDestructed)));
+    /// # Ok(())
+    /// # }
+    pub fn add_destructor(&'scope self, destructor: impl FnOnce() + 'env) {
+        self.user_destructors.0.borrow_mut().push(Box::new(destructor));
+    }
+
+    unsafe fn create_callback(&'scope self, f: ScopedCallback<'scope>) -> Result<Function> {
+        let f = mem::transmute::<ScopedCallback, Callback>(f);
         let f = self.lua.create_callback(f)?;
 
-        let mut destructors = self.destructors.borrow_mut();
-        destructors.push((f.0.clone(), |f| {
-            let state = f.lua.state;
-            assert_stack(state, 3);
-            f.lua.push_ref(&f);
+        let destructor: DestructorCallback = Box::new(|rawlua, vref| {
+            let ref_thread = rawlua.ref_thread();
+            ffi::lua_getupvalue(ref_thread, vref.index, 1);
+            let upvalue = get_userdata::<CallbackUpvalue>(ref_thread, -1);
+            let data = (*upvalue).data.take();
+            ffi::lua_pop(ref_thread, 1);
+            vec![Box::new(move || drop(data))]
+        });
+        self.destructors.0.borrow_mut().push((f.0.clone(), destructor));
 
-            ffi::lua_getupvalue(state, -1, 1);
-            // We know the destructor has not run yet because we hold a reference to the callback.
-            let ud = take_userdata::<Callback>(state);
-
-            ffi::lua_pushnil(state);
-            ffi::lua_setupvalue(state, -2, 1);
-
-            ffi::lua_pop(state, 1);
-            Box::new(ud)
-        }));
         Ok(f)
     }
-}
 
-impl<'lua, 'scope> Drop for Scope<'lua, 'scope> {
-    fn drop(&mut self) {
-        // We separate the action of invalidating the userdata in Lua and actually dropping the
-        // userdata type into two phases.  This is so that, in the event a userdata drop panics, we
-        // can be sure that all of the userdata in Lua is actually invalidated.
+    /// Shortens the lifetime of the userdata to the lifetime of the scope.
+    fn seal_userdata<T: 'env>(&self, ud: &AnyUserData) {
+        let destructor: DestructorCallback = Box::new(|rawlua, vref| unsafe {
+            // Ensure that userdata is not destructed
+            match rawlua.get_userdata_ref_type_id(&vref) {
+                Ok(Some(_)) => {}
+                Ok(None) => {
+                    // Deregister metatable
+                    let mt_ptr = get_metatable_ptr(rawlua.ref_thread(), vref.index);
+                    rawlua.deregister_userdata_metatable(mt_ptr);
+                }
+                Err(_) => return vec![],
+            }
 
-        // All destructors are non-panicking, so this is fine
-        let to_drop = self
-            .destructors
-            .get_mut()
-            .drain(..)
-            .map(|(r, dest)| dest(r))
-            .collect::<Vec<_>>();
-
-        drop(to_drop);
+            let data = take_userdata::<UserDataStorage<T>>(rawlua.ref_thread(), vref.index);
+            vec![Box::new(move || drop(data))]
+        });
+        self.destructors.0.borrow_mut().push((ud.0.clone(), destructor));
     }
 }
 
-enum NonStaticMethod<'lua, T> {
-    Method(Box<dyn Fn(&'lua Lua, &T, MultiValue<'lua>) -> Result<MultiValue<'lua>>>),
-    MethodMut(Box<dyn FnMut(&'lua Lua, &mut T, MultiValue<'lua>) -> Result<MultiValue<'lua>>>),
-    Function(Box<dyn Fn(&'lua Lua, MultiValue<'lua>) -> Result<MultiValue<'lua>>>),
-    FunctionMut(Box<dyn FnMut(&'lua Lua, MultiValue<'lua>) -> Result<MultiValue<'lua>>>),
-}
+impl Drop for Destructors<'_> {
+    fn drop(&mut self) {
+        // We separate the action of invalidating the userdata in Lua and actually dropping the
+        // userdata type into two phases. This is so that, in the event a userdata drop panics,
+        // we can be sure that all of the userdata in Lua is actually invalidated.
 
-struct NonStaticUserDataMethods<'lua, T: UserData> {
-    methods: Vec<(Vec<u8>, NonStaticMethod<'lua, T>)>,
-    meta_methods: Vec<(MetaMethod, NonStaticMethod<'lua, T>)>,
-}
+        let destructors = mem::take(&mut *self.0.borrow_mut());
+        if let Some(lua) = destructors.first().map(|(vref, _)| vref.lua.lock()) {
+            // All destructors are non-panicking, so this is fine
+            let to_drop = destructors
+                .into_iter()
+                .flat_map(|(vref, destructor)| destructor(&lua, vref))
+                .collect::<Vec<_>>();
 
-impl<'lua, T: UserData> Default for NonStaticUserDataMethods<'lua, T> {
-    fn default() -> NonStaticUserDataMethods<'lua, T> {
-        NonStaticUserDataMethods {
-            methods: Vec::new(),
-            meta_methods: Vec::new(),
+            drop(to_drop);
         }
     }
 }
 
-impl<'lua, T: UserData> UserDataMethods<'lua, T> for NonStaticUserDataMethods<'lua, T> {
-    fn add_method<S, A, R, M>(&mut self, name: &S, method: M)
-    where
-        S: ?Sized + AsRef<[u8]>,
-        A: FromLuaMulti<'lua>,
-        R: ToLuaMulti<'lua>,
-        M: 'static + Send + Fn(&'lua Lua, &T, A) -> Result<R>,
-    {
-        self.methods.push((
-            name.as_ref().to_vec(),
-            NonStaticMethod::Method(Box::new(move |lua, ud, args| {
-                method(lua, ud, A::from_lua_multi(args, lua)?)?.to_lua_multi(lua)
-            })),
-        ));
-    }
-
-    fn add_method_mut<S, A, R, M>(&mut self, name: &S, mut method: M)
-    where
-        S: ?Sized + AsRef<[u8]>,
-        A: FromLuaMulti<'lua>,
-        R: ToLuaMulti<'lua>,
-        M: 'static + Send + FnMut(&'lua Lua, &mut T, A) -> Result<R>,
-    {
-        self.methods.push((
-            name.as_ref().to_vec(),
-            NonStaticMethod::MethodMut(Box::new(move |lua, ud, args| {
-                method(lua, ud, A::from_lua_multi(args, lua)?)?.to_lua_multi(lua)
-            })),
-        ));
-    }
-
-    fn add_function<S, A, R, F>(&mut self, name: &S, function: F)
-    where
-        S: ?Sized + AsRef<[u8]>,
-        A: FromLuaMulti<'lua>,
-        R: ToLuaMulti<'lua>,
-        F: 'static + Send + Fn(&'lua Lua, A) -> Result<R>,
-    {
-        self.methods.push((
-            name.as_ref().to_vec(),
-            NonStaticMethod::Function(Box::new(move |lua, args| {
-                function(lua, A::from_lua_multi(args, lua)?)?.to_lua_multi(lua)
-            })),
-        ));
-    }
-
-    fn add_function_mut<S, A, R, F>(&mut self, name: &S, mut function: F)
-    where
-        S: ?Sized + AsRef<[u8]>,
-        A: FromLuaMulti<'lua>,
-        R: ToLuaMulti<'lua>,
-        F: 'static + Send + FnMut(&'lua Lua, A) -> Result<R>,
-    {
-        self.methods.push((
-            name.as_ref().to_vec(),
-            NonStaticMethod::FunctionMut(Box::new(move |lua, args| {
-                function(lua, A::from_lua_multi(args, lua)?)?.to_lua_multi(lua)
-            })),
-        ));
-    }
-
-    fn add_meta_method<A, R, M>(&mut self, meta: MetaMethod, method: M)
-    where
-        A: FromLuaMulti<'lua>,
-        R: ToLuaMulti<'lua>,
-        M: 'static + Send + Fn(&'lua Lua, &T, A) -> Result<R>,
-    {
-        self.meta_methods.push((
-            meta,
-            NonStaticMethod::Method(Box::new(move |lua, ud, args| {
-                method(lua, ud, A::from_lua_multi(args, lua)?)?.to_lua_multi(lua)
-            })),
-        ));
-    }
-
-    fn add_meta_method_mut<A, R, M>(&mut self, meta: MetaMethod, mut method: M)
-    where
-        A: FromLuaMulti<'lua>,
-        R: ToLuaMulti<'lua>,
-        M: 'static + Send + FnMut(&'lua Lua, &mut T, A) -> Result<R>,
-    {
-        self.meta_methods.push((
-            meta,
-            NonStaticMethod::MethodMut(Box::new(move |lua, ud, args| {
-                method(lua, ud, A::from_lua_multi(args, lua)?)?.to_lua_multi(lua)
-            })),
-        ));
-    }
-
-    fn add_meta_function<A, R, F>(&mut self, meta: MetaMethod, function: F)
-    where
-        A: FromLuaMulti<'lua>,
-        R: ToLuaMulti<'lua>,
-        F: 'static + Send + Fn(&'lua Lua, A) -> Result<R>,
-    {
-        self.meta_methods.push((
-            meta,
-            NonStaticMethod::Function(Box::new(move |lua, args| {
-                function(lua, A::from_lua_multi(args, lua)?)?.to_lua_multi(lua)
-            })),
-        ));
-    }
-
-    fn add_meta_function_mut<A, R, F>(&mut self, meta: MetaMethod, mut function: F)
-    where
-        A: FromLuaMulti<'lua>,
-        R: ToLuaMulti<'lua>,
-        F: 'static + Send + FnMut(&'lua Lua, A) -> Result<R>,
-    {
-        self.meta_methods.push((
-            meta,
-            NonStaticMethod::FunctionMut(Box::new(move |lua, args| {
-                function(lua, A::from_lua_multi(args, lua)?)?.to_lua_multi(lua)
-            })),
-        ));
+impl Drop for UserDestructors<'_> {
+    fn drop(&mut self) {
+        let destructors = mem::take(&mut *self.0.borrow_mut());
+        for destructor in destructors {
+            destructor();
+        }
     }
 }

src/serde/de.rs

@@ -0,0 +1,746 @@
+//! Deserialize Lua values to a Rust data structure.
+
+use std::cell::RefCell;
+use std::os::raw::c_void;
+use std::rc::Rc;
+use std::result::Result as StdResult;
+use std::string::String as StdString;
+
+use rustc_hash::FxHashSet;
+use serde::de::{self, IntoDeserializer};
+
+use crate::error::{Error, Result};
+use crate::table::{Table, TablePairs, TableSequence};
+use crate::userdata::AnyUserData;
+use crate::value::Value;
+
+/// A struct for deserializing Lua values into Rust values.
+#[derive(Debug)]
+pub struct Deserializer {
+    value: Value,
+    options: Options,
+    visited: Rc<RefCell<FxHashSet<*const c_void>>>,
+}
+
+/// A struct with options to change default deserializer behavior.
+#[derive(Debug, Clone, Copy)]
+#[non_exhaustive]
+pub struct Options {
+    /// If true, an attempt to serialize types such as [`Function`], [`Thread`], [`LightUserData`]
+    /// and [`Error`] will cause an error.
+    /// Otherwise these types skipped when iterating or serialized as unit type.
+    ///
+    /// Default: **true**
+    ///
+    /// [`Function`]: crate::Function
+    /// [`Thread`]: crate::Thread
+    /// [`LightUserData`]: crate::LightUserData
+    /// [`Error`]: crate::Error
+    pub deny_unsupported_types: bool,
+
+    /// If true, an attempt to serialize a recursive table (table that refers to itself)
+    /// will cause an error.
+    /// Otherwise subsequent attempts to serialize the same table will be ignored.
+    ///
+    /// Default: **true**
+    pub deny_recursive_tables: bool,
+
+    /// If true, keys in tables will be iterated in sorted order.
+    ///
+    /// Default: **false**
+    pub sort_keys: bool,
+
+    /// If true, empty Lua tables will be encoded as array, instead of map.
+    ///
+    /// Default: **false**
+    pub encode_empty_tables_as_array: bool,
+}
+
+impl Default for Options {
+    fn default() -> Self {
+        const { Self::new() }
+    }
+}
+
+impl Options {
+    /// Returns a new instance of `Options` with default parameters.
+    pub const fn new() -> Self {
+        Options {
+            deny_unsupported_types: true,
+            deny_recursive_tables: true,
+            sort_keys: false,
+            encode_empty_tables_as_array: false,
+        }
+    }
+
+    /// Sets [`deny_unsupported_types`] option.
+    ///
+    /// [`deny_unsupported_types`]: #structfield.deny_unsupported_types
+    #[must_use]
+    pub const fn deny_unsupported_types(mut self, enabled: bool) -> Self {
+        self.deny_unsupported_types = enabled;
+        self
+    }
+
+    /// Sets [`deny_recursive_tables`] option.
+    ///
+    /// [`deny_recursive_tables`]: #structfield.deny_recursive_tables
+    #[must_use]
+    pub const fn deny_recursive_tables(mut self, enabled: bool) -> Self {
+        self.deny_recursive_tables = enabled;
+        self
+    }
+
+    /// Sets [`sort_keys`] option.
+    ///
+    /// [`sort_keys`]: #structfield.sort_keys
+    #[must_use]
+    pub const fn sort_keys(mut self, enabled: bool) -> Self {
+        self.sort_keys = enabled;
+        self
+    }
+
+    /// Sets [`encode_empty_tables_as_array`] option.
+    ///
+    /// [`encode_empty_tables_as_array`]: #structfield.encode_empty_tables_as_array
+    #[must_use]
+    pub const fn encode_empty_tables_as_array(mut self, enabled: bool) -> Self {
+        self.encode_empty_tables_as_array = enabled;
+        self
+    }
+}
+
+impl Deserializer {
+    /// Creates a new Lua Deserializer for the [`Value`].
+    pub fn new(value: Value) -> Self {
+        Self::new_with_options(value, Options::default())
+    }
+
+    /// Creates a new Lua Deserializer for the [`Value`] with custom options.
+    pub fn new_with_options(value: Value, options: Options) -> Self {
+        Deserializer {
+            value,
+            options,
+            visited: Rc::new(RefCell::new(FxHashSet::default())),
+        }
+    }
+
+    fn from_parts(value: Value, options: Options, visited: Rc<RefCell<FxHashSet<*const c_void>>>) -> Self {
+        Deserializer {
+            value,
+            options,
+            visited,
+        }
+    }
+}
+
+impl<'de> serde::Deserializer<'de> for Deserializer {
+    type Error = Error;
+
+    #[inline]
+    fn deserialize_any<V>(self, visitor: V) -> Result<V::Value>
+    where
+        V: de::Visitor<'de>,
+    {
+        match self.value {
+            Value::Nil => visitor.visit_unit(),
+            Value::Boolean(b) => visitor.visit_bool(b),
+            #[allow(clippy::useless_conversion)]
+            Value::Integer(i) => visitor.visit_i64(i.into()),
+            #[allow(clippy::useless_conversion)]
+            Value::Number(n) => visitor.visit_f64(n.into()),
+            #[cfg(feature = "luau")]
+            Value::Vector(_) => self.deserialize_seq(visitor),
+            Value::String(s) => match s.to_str() {
+                Ok(s) => visitor.visit_str(&s),
+                Err(_) => visitor.visit_bytes(&s.as_bytes()),
+            },
+            Value::Table(ref t) if t.raw_len() > 0 || t.is_array() => self.deserialize_seq(visitor),
+            Value::Table(ref t) if self.options.encode_empty_tables_as_array && t.is_empty() => {
+                self.deserialize_seq(visitor)
+            }
+            Value::Table(_) => self.deserialize_map(visitor),
+            Value::LightUserData(ud) if ud.0.is_null() => visitor.visit_none(),
+            Value::UserData(ud) if ud.is_serializable() => {
+                serde_userdata(ud, |value| value.deserialize_any(visitor))
+            }
+            #[cfg(feature = "luau")]
+            Value::Buffer(buf) => {
+                let lua = buf.0.lua.lock();
+                visitor.visit_bytes(buf.as_slice(&lua))
+            }
+            Value::Function(_)
+            | Value::Thread(_)
+            | Value::UserData(_)
+            | Value::LightUserData(_)
+            | Value::Error(_)
+            | Value::Other(_) => {
+                if self.options.deny_unsupported_types {
+                    let msg = format!("unsupported value type `{}`", self.value.type_name());
+                    Err(de::Error::custom(msg))
+                } else {
+                    visitor.visit_unit()
+                }
+            }
+        }
+    }
+
+    #[inline]
+    fn deserialize_option<V>(self, visitor: V) -> Result<V::Value>
+    where
+        V: de::Visitor<'de>,
+    {
+        match self.value {
+            Value::Nil => visitor.visit_none(),
+            Value::LightUserData(ud) if ud.0.is_null() => visitor.visit_none(),
+            _ => visitor.visit_some(self),
+        }
+    }
+
+    #[inline]
+    fn deserialize_enum<V>(
+        self,
+        name: &'static str,
+        variants: &'static [&'static str],
+        visitor: V,
+    ) -> Result<V::Value>
+    where
+        V: de::Visitor<'de>,
+    {
+        let (variant, value, _guard) = match self.value {
+            Value::Table(table) => {
+                let _guard = RecursionGuard::new(&table, &self.visited);
+
+                let mut iter = table.pairs::<StdString, Value>();
+                let (variant, value) = match iter.next() {
+                    Some(v) => v?,
+                    None => {
+                        return Err(de::Error::invalid_value(
+                            de::Unexpected::Map,
+                            &"map with a single key",
+                        ))
+                    }
+                };
+
+                if iter.next().is_some() {
+                    return Err(de::Error::invalid_value(
+                        de::Unexpected::Map,
+                        &"map with a single key",
+                    ));
+                }
+                let skip = check_value_for_skip(&value, self.options, &self.visited)
+                    .map_err(|err| Error::DeserializeError(err.to_string()))?;
+                if skip {
+                    return Err(de::Error::custom("bad enum value"));
+                }
+
+                (variant, Some(value), Some(_guard))
+            }
+            Value::String(variant) => (variant.to_str()?.to_owned(), None, None),
+            Value::UserData(ud) if ud.is_serializable() => {
+                return serde_userdata(ud, |value| value.deserialize_enum(name, variants, visitor));
+            }
+            _ => return Err(de::Error::custom("bad enum value")),
+        };
+
+        visitor.visit_enum(EnumDeserializer {
+            variant,
+            value,
+            options: self.options,
+            visited: self.visited,
+        })
+    }
+
+    #[inline]
+    fn deserialize_seq<V>(self, visitor: V) -> Result<V::Value>
+    where
+        V: de::Visitor<'de>,
+    {
+        match self.value {
+            #[cfg(feature = "luau")]
+            Value::Vector(vec) => {
+                let mut deserializer = VecDeserializer {
+                    vec,
+                    next: 0,
+                    options: self.options,
+                    visited: self.visited,
+                };
+                visitor.visit_seq(&mut deserializer)
+            }
+            Value::Table(t) => {
+                let _guard = RecursionGuard::new(&t, &self.visited);
+
+                let len = t.raw_len();
+                let mut deserializer = SeqDeserializer {
+                    seq: t.sequence_values(),
+                    options: self.options,
+                    visited: self.visited,
+                };
+                let seq = visitor.visit_seq(&mut deserializer)?;
+                if deserializer.seq.count() == 0 {
+                    Ok(seq)
+                } else {
+                    Err(de::Error::invalid_length(len, &"fewer elements in the table"))
+                }
+            }
+            Value::UserData(ud) if ud.is_serializable() => {
+                serde_userdata(ud, |value| value.deserialize_seq(visitor))
+            }
+            value => Err(de::Error::invalid_type(
+                de::Unexpected::Other(value.type_name()),
+                &"table",
+            )),
+        }
+    }
+
+    #[inline]
+    fn deserialize_tuple<V>(self, _len: usize, visitor: V) -> Result<V::Value>
+    where
+        V: de::Visitor<'de>,
+    {
+        self.deserialize_seq(visitor)
+    }
+
+    #[inline]
+    fn deserialize_tuple_struct<V>(self, _name: &'static str, _len: usize, visitor: V) -> Result<V::Value>
+    where
+        V: de::Visitor<'de>,
+    {
+        self.deserialize_seq(visitor)
+    }
+
+    #[inline]
+    fn deserialize_map<V>(self, visitor: V) -> Result<V::Value>
+    where
+        V: de::Visitor<'de>,
+    {
+        match self.value {
+            Value::Table(t) => {
+                let _guard = RecursionGuard::new(&t, &self.visited);
+
+                let mut deserializer = MapDeserializer {
+                    pairs: MapPairs::new(&t, self.options.sort_keys)?,
+                    value: None,
+                    options: self.options,
+                    visited: self.visited,
+                    processed: 0,
+                };
+                let map = visitor.visit_map(&mut deserializer)?;
+                let count = deserializer.pairs.count();
+                if count == 0 {
+                    Ok(map)
+                } else {
+                    Err(de::Error::invalid_length(
+                        deserializer.processed + count,
+                        &"fewer elements in the table",
+                    ))
+                }
+            }
+            Value::UserData(ud) if ud.is_serializable() => {
+                serde_userdata(ud, |value| value.deserialize_map(visitor))
+            }
+            value => Err(de::Error::invalid_type(
+                de::Unexpected::Other(value.type_name()),
+                &"table",
+            )),
+        }
+    }
+
+    #[inline]
+    fn deserialize_struct<V>(
+        self,
+        _name: &'static str,
+        _fields: &'static [&'static str],
+        visitor: V,
+    ) -> Result<V::Value>
+    where
+        V: de::Visitor<'de>,
+    {
+        self.deserialize_map(visitor)
+    }
+
+    #[inline]
+    fn deserialize_newtype_struct<V>(self, name: &'static str, visitor: V) -> Result<V::Value>
+    where
+        V: de::Visitor<'de>,
+    {
+        match self.value {
+            Value::UserData(ud) if ud.is_serializable() => {
+                serde_userdata(ud, |value| value.deserialize_newtype_struct(name, visitor))
+            }
+            _ => visitor.visit_newtype_struct(self),
+        }
+    }
+
+    #[inline]
+    fn deserialize_unit<V>(self, visitor: V) -> Result<V::Value>
+    where
+        V: de::Visitor<'de>,
+    {
+        match self.value {
+            Value::LightUserData(ud) if ud.0.is_null() => visitor.visit_unit(),
+            _ => self.deserialize_any(visitor),
+        }
+    }
+
+    #[inline]
+    fn deserialize_unit_struct<V>(self, _name: &'static str, visitor: V) -> Result<V::Value>
+    where
+        V: de::Visitor<'de>,
+    {
+        match self.value {
+            Value::LightUserData(ud) if ud.0.is_null() => visitor.visit_unit(),
+            _ => self.deserialize_any(visitor),
+        }
+    }
+
+    serde::forward_to_deserialize_any! {
+        bool i8 i16 i32 i64 i128 u8 u16 u32 u64 u128 f32 f64 char str string bytes
+        byte_buf identifier ignored_any
+    }
+}
+
+struct SeqDeserializer<'a> {
+    seq: TableSequence<'a, Value>,
+    options: Options,
+    visited: Rc<RefCell<FxHashSet<*const c_void>>>,
+}
+
+impl<'de> de::SeqAccess<'de> for SeqDeserializer<'_> {
+    type Error = Error;
+
+    fn next_element_seed<T>(&mut self, seed: T) -> Result<Option<T::Value>>
+    where
+        T: de::DeserializeSeed<'de>,
+    {
+        loop {
+            match self.seq.next() {
+                Some(value) => {
+                    let value = value?;
+                    let skip = check_value_for_skip(&value, self.options, &self.visited)
+                        .map_err(|err| Error::DeserializeError(err.to_string()))?;
+                    if skip {
+                        continue;
+                    }
+                    let visited = Rc::clone(&self.visited);
+                    let deserializer = Deserializer::from_parts(value, self.options, visited);
+                    return seed.deserialize(deserializer).map(Some);
+                }
+                None => return Ok(None),
+            }
+        }
+    }
+
+    fn size_hint(&self) -> Option<usize> {
+        match self.seq.size_hint() {
+            (lower, Some(upper)) if lower == upper => Some(upper),
+            _ => None,
+        }
+    }
+}
+
+#[cfg(feature = "luau")]
+struct VecDeserializer {
+    vec: crate::Vector,
+    next: usize,
+    options: Options,
+    visited: Rc<RefCell<FxHashSet<*const c_void>>>,
+}
+
+#[cfg(feature = "luau")]
+impl<'de> de::SeqAccess<'de> for VecDeserializer {
+    type Error = Error;
+
+    fn next_element_seed<T>(&mut self, seed: T) -> Result<Option<T::Value>>
+    where
+        T: de::DeserializeSeed<'de>,
+    {
+        match self.vec.0.get(self.next) {
+            Some(&n) => {
+                self.next += 1;
+                let visited = Rc::clone(&self.visited);
+                let deserializer = Deserializer::from_parts(Value::Number(n as _), self.options, visited);
+                seed.deserialize(deserializer).map(Some)
+            }
+            None => Ok(None),
+        }
+    }
+
+    fn size_hint(&self) -> Option<usize> {
+        Some(crate::Vector::SIZE)
+    }
+}
+
+pub(crate) enum MapPairs<'a> {
+    Iter(TablePairs<'a, Value, Value>),
+    Vec(Vec<(Value, Value)>),
+}
+
+impl<'a> MapPairs<'a> {
+    pub(crate) fn new(t: &'a Table, sort_keys: bool) -> Result<Self> {
+        if sort_keys {
+            let mut pairs = t.pairs::<Value, Value>().collect::<Result<Vec<_>>>()?;
+            pairs.sort_by(|(a, _), (b, _)| b.sort_cmp(a)); // reverse order as we pop values from the end
+            Ok(MapPairs::Vec(pairs))
+        } else {
+            Ok(MapPairs::Iter(t.pairs::<Value, Value>()))
+        }
+    }
+
+    pub(crate) fn count(self) -> usize {
+        match self {
+            MapPairs::Iter(iter) => iter.count(),
+            MapPairs::Vec(vec) => vec.len(),
+        }
+    }
+
+    pub(crate) fn size_hint(&self) -> (usize, Option<usize>) {
+        match self {
+            MapPairs::Iter(iter) => iter.size_hint(),
+            MapPairs::Vec(vec) => (vec.len(), Some(vec.len())),
+        }
+    }
+}
+
+impl Iterator for MapPairs<'_> {
+    type Item = Result<(Value, Value)>;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        match self {
+            MapPairs::Iter(iter) => iter.next(),
+            MapPairs::Vec(vec) => vec.pop().map(Ok),
+        }
+    }
+}
+
+struct MapDeserializer<'a> {
+    pairs: MapPairs<'a>,
+    value: Option<Value>,
+    options: Options,
+    visited: Rc<RefCell<FxHashSet<*const c_void>>>,
+    processed: usize,
+}
+
+impl MapDeserializer<'_> {
+    fn next_key_deserializer(&mut self) -> Result<Option<Deserializer>> {
+        loop {
+            match self.pairs.next() {
+                Some(item) => {
+                    let (key, value) = item?;
+                    let skip_key = check_value_for_skip(&key, self.options, &self.visited)
+                        .map_err(|err| Error::DeserializeError(err.to_string()))?;
+                    let skip_value = check_value_for_skip(&value, self.options, &self.visited)
+                        .map_err(|err| Error::DeserializeError(err.to_string()))?;
+                    if skip_key || skip_value {
+                        continue;
+                    }
+                    self.processed += 1;
+                    self.value = Some(value);
+                    let visited = Rc::clone(&self.visited);
+                    let key_de = Deserializer::from_parts(key, self.options, visited);
+                    return Ok(Some(key_de));
+                }
+                None => return Ok(None),
+            }
+        }
+    }
+
+    fn next_value_deserializer(&mut self) -> Result<Deserializer> {
+        match self.value.take() {
+            Some(value) => {
+                let visited = Rc::clone(&self.visited);
+                Ok(Deserializer::from_parts(value, self.options, visited))
+            }
+            None => Err(de::Error::custom("value is missing")),
+        }
+    }
+}
+
+impl<'de> de::MapAccess<'de> for MapDeserializer<'_> {
+    type Error = Error;
+
+    fn next_key_seed<T>(&mut self, seed: T) -> Result<Option<T::Value>>
+    where
+        T: de::DeserializeSeed<'de>,
+    {
+        match self.next_key_deserializer() {
+            Ok(Some(key_de)) => seed.deserialize(key_de).map(Some),
+            Ok(None) => Ok(None),
+            Err(error) => Err(error),
+        }
+    }
+
+    fn next_value_seed<T>(&mut self, seed: T) -> Result<T::Value>
+    where
+        T: de::DeserializeSeed<'de>,
+    {
+        match self.next_value_deserializer() {
+            Ok(value_de) => seed.deserialize(value_de),
+            Err(error) => Err(error),
+        }
+    }
+
+    fn size_hint(&self) -> Option<usize> {
+        match self.pairs.size_hint() {
+            (lower, Some(upper)) if lower == upper => Some(upper),
+            _ => None,
+        }
+    }
+}
+
+struct EnumDeserializer {
+    variant: StdString,
+    value: Option<Value>,
+    options: Options,
+    visited: Rc<RefCell<FxHashSet<*const c_void>>>,
+}
+
+impl<'de> de::EnumAccess<'de> for EnumDeserializer {
+    type Error = Error;
+    type Variant = VariantDeserializer;
+
+    fn variant_seed<T>(self, seed: T) -> Result<(T::Value, Self::Variant)>
+    where
+        T: de::DeserializeSeed<'de>,
+    {
+        let variant = self.variant.into_deserializer();
+        let variant_access = VariantDeserializer {
+            value: self.value,
+            options: self.options,
+            visited: self.visited,
+        };
+        seed.deserialize(variant).map(|v| (v, variant_access))
+    }
+}
+
+struct VariantDeserializer {
+    value: Option<Value>,
+    options: Options,
+    visited: Rc<RefCell<FxHashSet<*const c_void>>>,
+}
+
+impl<'de> de::VariantAccess<'de> for VariantDeserializer {
+    type Error = Error;
+
+    fn unit_variant(self) -> Result<()> {
+        match self.value {
+            Some(_) => Err(de::Error::invalid_type(
+                de::Unexpected::NewtypeVariant,
+                &"unit variant",
+            )),
+            None => Ok(()),
+        }
+    }
+
+    fn newtype_variant_seed<T>(self, seed: T) -> Result<T::Value>
+    where
+        T: de::DeserializeSeed<'de>,
+    {
+        match self.value {
+            Some(value) => seed.deserialize(Deserializer::from_parts(value, self.options, self.visited)),
+            None => Err(de::Error::invalid_type(
+                de::Unexpected::UnitVariant,
+                &"newtype variant",
+            )),
+        }
+    }
+
+    fn tuple_variant<V>(self, _len: usize, visitor: V) -> Result<V::Value>
+    where
+        V: de::Visitor<'de>,
+    {
+        match self.value {
+            Some(value) => serde::Deserializer::deserialize_seq(
+                Deserializer::from_parts(value, self.options, self.visited),
+                visitor,
+            ),
+            None => Err(de::Error::invalid_type(
+                de::Unexpected::UnitVariant,
+                &"tuple variant",
+            )),
+        }
+    }
+
+    fn struct_variant<V>(self, _fields: &'static [&'static str], visitor: V) -> Result<V::Value>
+    where
+        V: de::Visitor<'de>,
+    {
+        match self.value {
+            Some(value) => serde::Deserializer::deserialize_map(
+                Deserializer::from_parts(value, self.options, self.visited),
+                visitor,
+            ),
+            None => Err(de::Error::invalid_type(
+                de::Unexpected::UnitVariant,
+                &"struct variant",
+            )),
+        }
+    }
+}
+
+// Adds `ptr` to the `visited` map and removes on drop
+// Used to track recursive tables but allow to traverse same tables multiple times
+pub(crate) struct RecursionGuard {
+    ptr: *const c_void,
+    visited: Rc<RefCell<FxHashSet<*const c_void>>>,
+}
+
+impl RecursionGuard {
+    #[inline]
+    pub(crate) fn new(table: &Table, visited: &Rc<RefCell<FxHashSet<*const c_void>>>) -> Self {
+        let visited = Rc::clone(visited);
+        let ptr = table.to_pointer();
+        visited.borrow_mut().insert(ptr);
+        RecursionGuard { ptr, visited }
+    }
+}
+
+impl Drop for RecursionGuard {
+    fn drop(&mut self) {
+        self.visited.borrow_mut().remove(&self.ptr);
+    }
+}
+
+// Checks `options` and decides should we emit an error or skip next element
+pub(crate) fn check_value_for_skip(
+    value: &Value,
+    options: Options,
+    visited: &RefCell<FxHashSet<*const c_void>>,
+) -> StdResult<bool, &'static str> {
+    match value {
+        Value::Table(table) => {
+            let ptr = table.to_pointer();
+            if visited.borrow().contains(&ptr) {
+                if options.deny_recursive_tables {
+                    return Err("recursive table detected");
+                }
+                return Ok(true); // skip
+            }
+        }
+        Value::UserData(ud) if ud.is_serializable() => {}
+        Value::Function(_)
+        | Value::Thread(_)
+        | Value::UserData(_)
+        | Value::LightUserData(_)
+        | Value::Error(_)
+            if !options.deny_unsupported_types =>
+        {
+            return Ok(true); // skip
+        }
+        _ => {}
+    }
+    Ok(false) // do not skip
+}
+
+fn serde_userdata<V>(
+    ud: AnyUserData,
+    f: impl FnOnce(serde_value::Value) -> std::result::Result<V, serde_value::DeserializerError>,
+) -> Result<V> {
+    match serde_value::to_value(ud) {
+        Ok(value) => match f(value) {
+            Ok(r) => Ok(r),
+            Err(error) => Err(Error::DeserializeError(error.to_string())),
+        },
+        Err(error) => Err(Error::SerializeError(error.to_string())),
+    }
+}

src/serde/mod.rs

@@ -0,0 +1,248 @@
+//! (De)Serialization support using serde.
+
+use std::os::raw::c_void;
+
+use serde::de::DeserializeOwned;
+use serde::ser::Serialize;
+
+use crate::error::Result;
+use crate::private::Sealed;
+use crate::state::Lua;
+use crate::table::Table;
+use crate::util::check_stack;
+use crate::value::Value;
+
+/// Trait for serializing/deserializing Lua values using Serde.
+#[cfg_attr(docsrs, doc(cfg(feature = "serde")))]
+pub trait LuaSerdeExt: Sealed {
+    /// A special value (lightuserdata) to encode/decode optional (none) values.
+    ///
+    /// # Example
+    ///
+    /// ```
+    /// use std::collections::HashMap;
+    /// use mlua::{Lua, Result, LuaSerdeExt};
+    ///
+    /// fn main() -> Result<()> {
+    ///     let lua = Lua::new();
+    ///     lua.globals().set("null", lua.null())?;
+    ///
+    ///     let val = lua.load(r#"{a = null}"#).eval()?;
+    ///     let map: HashMap<String, Option<String>> = lua.from_value(val)?;
+    ///     assert_eq!(map["a"], None);
+    ///
+    ///     Ok(())
+    /// }
+    /// ```
+    fn null(&self) -> Value;
+
+    /// A metatable attachable to a Lua table to systematically encode it as Array (instead of Map).
+    /// As result, encoded Array will contain only sequence part of the table, with the same length
+    /// as the `#` operator on that table.
+    ///
+    /// # Example
+    ///
+    /// ```
+    /// use mlua::{Lua, Result, LuaSerdeExt};
+    /// use serde_json::Value as JsonValue;
+    ///
+    /// fn main() -> Result<()> {
+    ///     let lua = Lua::new();
+    ///     lua.globals().set("array_mt", lua.array_metatable())?;
+    ///
+    ///     // Encode as an empty array (no sequence part in the lua table)
+    ///     let val = lua.load("setmetatable({a = 5}, array_mt)").eval()?;
+    ///     let j: JsonValue = lua.from_value(val)?;
+    ///     assert_eq!(j.to_string(), "[]");
+    ///
+    ///     // Encode as object
+    ///     let val = lua.load("{a = 5}").eval()?;
+    ///     let j: JsonValue = lua.from_value(val)?;
+    ///     assert_eq!(j.to_string(), r#"{"a":5}"#);
+    ///
+    ///     Ok(())
+    /// }
+    /// ```
+    fn array_metatable(&self) -> Table;
+
+    /// Converts `T` into a [`Value`] instance.
+    ///
+    /// [`Value`]: crate::Value
+    ///
+    /// # Example
+    ///
+    /// ```
+    /// use mlua::{Lua, Result, LuaSerdeExt};
+    /// use serde::Serialize;
+    ///
+    /// #[derive(Serialize)]
+    /// struct User {
+    ///     name: String,
+    ///     age: u8,
+    /// }
+    ///
+    /// fn main() -> Result<()> {
+    ///     let lua = Lua::new();
+    ///     let u = User {
+    ///         name: "John Smith".into(),
+    ///         age: 20,
+    ///     };
+    ///     lua.globals().set("user", lua.to_value(&u)?)?;
+    ///     lua.load(r#"
+    ///         assert(user["name"] == "John Smith")
+    ///         assert(user["age"] == 20)
+    ///     "#).exec()
+    /// }
+    /// ```
+    fn to_value<T: Serialize + ?Sized>(&self, t: &T) -> Result<Value>;
+
+    /// Converts `T` into a [`Value`] instance with options.
+    ///
+    /// # Example
+    ///
+    /// ```
+    /// use mlua::{Lua, Result, LuaSerdeExt, SerializeOptions};
+    ///
+    /// fn main() -> Result<()> {
+    ///     let lua = Lua::new();
+    ///     let v = vec![1, 2, 3];
+    ///     let options = SerializeOptions::new().set_array_metatable(false);
+    ///     lua.globals().set("v", lua.to_value_with(&v, options)?)?;
+    ///
+    ///     lua.load(r#"
+    ///         assert(#v == 3 and v[1] == 1 and v[2] == 2 and v[3] == 3)
+    ///         assert(getmetatable(v) == nil)
+    ///     "#).exec()
+    /// }
+    /// ```
+    fn to_value_with<T>(&self, t: &T, options: ser::Options) -> Result<Value>
+    where
+        T: Serialize + ?Sized;
+
+    /// Deserializes a [`Value`] into any serde deserializable object.
+    ///
+    /// # Example
+    ///
+    /// ```
+    /// use mlua::{Lua, Result, LuaSerdeExt};
+    /// use serde::Deserialize;
+    ///
+    /// #[derive(Deserialize, Debug, PartialEq)]
+    /// struct User {
+    ///     name: String,
+    ///     age: u8,
+    /// }
+    ///
+    /// fn main() -> Result<()> {
+    ///     let lua = Lua::new();
+    ///     let val = lua.load(r#"{name = "John Smith", age = 20}"#).eval()?;
+    ///     let u: User = lua.from_value(val)?;
+    ///
+    ///     assert_eq!(u, User { name: "John Smith".into(), age: 20 });
+    ///
+    ///     Ok(())
+    /// }
+    /// ```
+    #[allow(clippy::wrong_self_convention)]
+    fn from_value<T: DeserializeOwned>(&self, value: Value) -> Result<T>;
+
+    /// Deserializes a [`Value`] into any serde deserializable object with options.
+    ///
+    /// # Example
+    ///
+    /// ```
+    /// use mlua::{Lua, Result, LuaSerdeExt, DeserializeOptions};
+    /// use serde::Deserialize;
+    ///
+    /// #[derive(Deserialize, Debug, PartialEq)]
+    /// struct User {
+    ///     name: String,
+    ///     age: u8,
+    /// }
+    ///
+    /// fn main() -> Result<()> {
+    ///     let lua = Lua::new();
+    ///     let val = lua.load(r#"{name = "John Smith", age = 20, f = function() end}"#).eval()?;
+    ///     let options = DeserializeOptions::new().deny_unsupported_types(false);
+    ///     let u: User = lua.from_value_with(val, options)?;
+    ///
+    ///     assert_eq!(u, User { name: "John Smith".into(), age: 20 });
+    ///
+    ///     Ok(())
+    /// }
+    /// ```
+    #[allow(clippy::wrong_self_convention)]
+    fn from_value_with<T: DeserializeOwned>(&self, value: Value, options: de::Options) -> Result<T>;
+}
+
+impl LuaSerdeExt for Lua {
+    fn null(&self) -> Value {
+        Value::NULL
+    }
+
+    fn array_metatable(&self) -> Table {
+        let lua = self.lock();
+        unsafe {
+            push_array_metatable(lua.ref_thread());
+            Table(lua.pop_ref_thread())
+        }
+    }
+
+    fn to_value<T>(&self, t: &T) -> Result<Value>
+    where
+        T: Serialize + ?Sized,
+    {
+        t.serialize(ser::Serializer::new(self))
+    }
+
+    fn to_value_with<T>(&self, t: &T, options: ser::Options) -> Result<Value>
+    where
+        T: Serialize + ?Sized,
+    {
+        t.serialize(ser::Serializer::new_with_options(self, options))
+    }
+
+    fn from_value<T>(&self, value: Value) -> Result<T>
+    where
+        T: DeserializeOwned,
+    {
+        T::deserialize(de::Deserializer::new(value))
+    }
+
+    fn from_value_with<T>(&self, value: Value, options: de::Options) -> Result<T>
+    where
+        T: DeserializeOwned,
+    {
+        T::deserialize(de::Deserializer::new_with_options(value, options))
+    }
+}
+
+// Uses 2 stack spaces and calls checkstack.
+pub(crate) unsafe fn init_metatables(state: *mut ffi::lua_State) -> Result<()> {
+    check_stack(state, 2)?;
+    protect_lua!(state, 0, 0, fn(state) {
+        ffi::lua_createtable(state, 0, 1);
+
+        ffi::lua_pushstring(state, cstr!("__metatable"));
+        ffi::lua_pushboolean(state, 0);
+        ffi::lua_rawset(state, -3);
+
+        let array_metatable_key = &ARRAY_METATABLE_REGISTRY_KEY as *const u8 as *const c_void;
+        ffi::lua_rawsetp(state, ffi::LUA_REGISTRYINDEX, array_metatable_key);
+    })
+}
+
+pub(crate) unsafe fn push_array_metatable(state: *mut ffi::lua_State) {
+    let array_metatable_key = &ARRAY_METATABLE_REGISTRY_KEY as *const u8 as *const c_void;
+    ffi::lua_rawgetp(state, ffi::LUA_REGISTRYINDEX, array_metatable_key);
+}
+
+static ARRAY_METATABLE_REGISTRY_KEY: u8 = 0;
+
+pub mod de;
+pub mod ser;
+
+#[doc(inline)]
+pub use de::Deserializer;
+#[doc(inline)]
+pub use ser::Serializer;

src/serde/ser.rs

@@ -0,0 +1,576 @@
+//! Serialize a Rust data structure into Lua value.
+
+use serde::{ser, Serialize};
+
+use super::LuaSerdeExt;
+use crate::error::{Error, Result};
+use crate::state::Lua;
+use crate::table::Table;
+use crate::traits::IntoLua;
+use crate::value::Value;
+
+/// A struct for serializing Rust values into Lua values.
+#[derive(Debug)]
+pub struct Serializer<'a> {
+    lua: &'a Lua,
+    options: Options,
+}
+
+/// A struct with options to change default serializer behavior.
+#[derive(Debug, Clone, Copy)]
+#[non_exhaustive]
+pub struct Options {
+    /// If true, sequence serialization to a Lua table will create table
+    /// with the [`array_metatable`] attached.
+    ///
+    /// Default: **true**
+    ///
+    /// [`array_metatable`]: crate::LuaSerdeExt::array_metatable
+    pub set_array_metatable: bool,
+
+    /// If true, serialize `None` (part of the `Option` type) to [`null`].
+    /// Otherwise it will be set to Lua [`Nil`].
+    ///
+    /// Default: **true**
+    ///
+    /// [`null`]: crate::LuaSerdeExt::null
+    /// [`Nil`]: crate::Value::Nil
+    pub serialize_none_to_null: bool,
+
+    /// If true, serialize `Unit` (type of `()` in Rust) and Unit structs to [`null`].
+    /// Otherwise it will be set to Lua [`Nil`].
+    ///
+    /// Default: **true**
+    ///
+    /// [`null`]: crate::LuaSerdeExt::null
+    /// [`Nil`]: crate::Value::Nil
+    pub serialize_unit_to_null: bool,
+
+    /// If true, serialize `serde_json::Number` with arbitrary_precision to a Lua number.
+    /// Otherwise it will be serialized as an object (what serde does).
+    ///
+    /// Default: **false**
+    pub detect_serde_json_arbitrary_precision: bool,
+}
+
+impl Default for Options {
+    fn default() -> Self {
+        const { Self::new() }
+    }
+}
+
+impl Options {
+    /// Returns a new instance of [`Options`] with default parameters.
+    pub const fn new() -> Self {
+        Options {
+            set_array_metatable: true,
+            serialize_none_to_null: true,
+            serialize_unit_to_null: true,
+            detect_serde_json_arbitrary_precision: false,
+        }
+    }
+
+    /// Sets [`set_array_metatable`] option.
+    ///
+    /// [`set_array_metatable`]: #structfield.set_array_metatable
+    #[must_use]
+    pub const fn set_array_metatable(mut self, enabled: bool) -> Self {
+        self.set_array_metatable = enabled;
+        self
+    }
+
+    /// Sets [`serialize_none_to_null`] option.
+    ///
+    /// [`serialize_none_to_null`]: #structfield.serialize_none_to_null
+    #[must_use]
+    pub const fn serialize_none_to_null(mut self, enabled: bool) -> Self {
+        self.serialize_none_to_null = enabled;
+        self
+    }
+
+    /// Sets [`serialize_unit_to_null`] option.
+    ///
+    /// [`serialize_unit_to_null`]: #structfield.serialize_unit_to_null
+    #[must_use]
+    pub const fn serialize_unit_to_null(mut self, enabled: bool) -> Self {
+        self.serialize_unit_to_null = enabled;
+        self
+    }
+
+    /// Sets [`detect_serde_json_arbitrary_precision`] option.
+    ///
+    /// This option is used to serialize `serde_json::Number` with arbitrary precision to a Lua
+    /// number. Otherwise it will be serialized as an object (what serde does).
+    ///
+    /// This option is disabled by default.
+    ///
+    /// [`detect_serde_json_arbitrary_precision`]: #structfield.detect_serde_json_arbitrary_precision
+    #[must_use]
+    pub const fn detect_serde_json_arbitrary_precision(mut self, enabled: bool) -> Self {
+        self.detect_serde_json_arbitrary_precision = enabled;
+        self
+    }
+}
+
+impl<'a> Serializer<'a> {
+    /// Creates a new Lua Serializer with default options.
+    pub fn new(lua: &'a Lua) -> Self {
+        Self::new_with_options(lua, Options::default())
+    }
+
+    /// Creates a new Lua Serializer with custom options.
+    pub fn new_with_options(lua: &'a Lua, options: Options) -> Self {
+        Serializer { lua, options }
+    }
+}
+
+macro_rules! lua_serialize_number {
+    ($name:ident, $t:ty) => {
+        #[inline]
+        fn $name(self, value: $t) -> Result<Value> {
+            value.into_lua(self.lua)
+        }
+    };
+}
+
+impl<'a> ser::Serializer for Serializer<'a> {
+    type Ok = Value;
+    type Error = Error;
+
+    // Associated types for keeping track of additional state while serializing
+    // compound data structures like sequences and maps.
+    type SerializeSeq = SerializeSeq<'a>;
+    type SerializeTuple = SerializeSeq<'a>;
+    type SerializeTupleStruct = SerializeSeq<'a>;
+    type SerializeTupleVariant = SerializeTupleVariant<'a>;
+    type SerializeMap = SerializeMap<'a>;
+    type SerializeStruct = SerializeStruct<'a>;
+    type SerializeStructVariant = SerializeStructVariant<'a>;
+
+    #[inline]
+    fn serialize_bool(self, value: bool) -> Result<Value> {
+        Ok(Value::Boolean(value))
+    }
+
+    lua_serialize_number!(serialize_i8, i8);
+    lua_serialize_number!(serialize_u8, u8);
+    lua_serialize_number!(serialize_i16, i16);
+    lua_serialize_number!(serialize_u16, u16);
+    lua_serialize_number!(serialize_i32, i32);
+    lua_serialize_number!(serialize_u32, u32);
+    lua_serialize_number!(serialize_i64, i64);
+    lua_serialize_number!(serialize_u64, u64);
+    lua_serialize_number!(serialize_i128, i128);
+    lua_serialize_number!(serialize_u128, u128);
+
+    lua_serialize_number!(serialize_f32, f32);
+    lua_serialize_number!(serialize_f64, f64);
+
+    #[inline]
+    fn serialize_char(self, value: char) -> Result<Value> {
+        self.serialize_str(&value.to_string())
+    }
+
+    #[inline]
+    fn serialize_str(self, value: &str) -> Result<Value> {
+        self.lua.create_string(value).map(Value::String)
+    }
+
+    #[inline]
+    fn serialize_bytes(self, value: &[u8]) -> Result<Value> {
+        self.lua.create_string(value).map(Value::String)
+    }
+
+    #[inline]
+    fn serialize_none(self) -> Result<Value> {
+        if self.options.serialize_none_to_null {
+            Ok(self.lua.null())
+        } else {
+            Ok(Value::Nil)
+        }
+    }
+
+    #[inline]
+    fn serialize_some<T>(self, value: &T) -> Result<Value>
+    where
+        T: Serialize + ?Sized,
+    {
+        value.serialize(self)
+    }
+
+    #[inline]
+    fn serialize_unit(self) -> Result<Value> {
+        if self.options.serialize_unit_to_null {
+            Ok(self.lua.null())
+        } else {
+            Ok(Value::Nil)
+        }
+    }
+
+    #[inline]
+    fn serialize_unit_struct(self, _name: &'static str) -> Result<Value> {
+        if self.options.serialize_unit_to_null {
+            Ok(self.lua.null())
+        } else {
+            Ok(Value::Nil)
+        }
+    }
+
+    #[inline]
+    fn serialize_unit_variant(
+        self,
+        _name: &'static str,
+        _variant_index: u32,
+        variant: &'static str,
+    ) -> Result<Value> {
+        self.serialize_str(variant)
+    }
+
+    #[inline]
+    fn serialize_newtype_struct<T>(self, _name: &'static str, value: &T) -> Result<Value>
+    where
+        T: Serialize + ?Sized,
+    {
+        value.serialize(self)
+    }
+
+    #[inline]
+    fn serialize_newtype_variant<T>(
+        self,
+        _name: &'static str,
+        _variant_index: u32,
+        variant: &'static str,
+        value: &T,
+    ) -> Result<Value>
+    where
+        T: Serialize + ?Sized,
+    {
+        let table = self.lua.create_table()?;
+        let variant = self.lua.create_string(variant)?;
+        let value = self.lua.to_value_with(value, self.options)?;
+        table.raw_set(variant, value)?;
+        Ok(Value::Table(table))
+    }
+
+    #[inline]
+    fn serialize_seq(self, len: Option<usize>) -> Result<Self::SerializeSeq> {
+        let table = self.lua.create_table_with_capacity(len.unwrap_or(0), 0)?;
+        if self.options.set_array_metatable {
+            table.set_metatable(Some(self.lua.array_metatable()))?;
+        }
+        Ok(SerializeSeq::new(self.lua, table, self.options))
+    }
+
+    #[inline]
+    fn serialize_tuple(self, len: usize) -> Result<Self::SerializeTuple> {
+        self.serialize_seq(Some(len))
+    }
+
+    #[inline]
+    fn serialize_tuple_struct(self, name: &'static str, len: usize) -> Result<Self::SerializeTupleStruct> {
+        #[cfg(feature = "luau")]
+        if name == "Vector" && len == crate::Vector::SIZE {
+            return Ok(SerializeSeq::new_vector(self.lua, self.options));
+        }
+        _ = name;
+        self.serialize_seq(Some(len))
+    }
+
+    #[inline]
+    fn serialize_tuple_variant(
+        self,
+        _name: &'static str,
+        _variant_index: u32,
+        variant: &'static str,
+        _len: usize,
+    ) -> Result<Self::SerializeTupleVariant> {
+        Ok(SerializeTupleVariant {
+            lua: self.lua,
+            variant,
+            table: self.lua.create_table()?,
+            options: self.options,
+        })
+    }
+
+    #[inline]
+    fn serialize_map(self, len: Option<usize>) -> Result<Self::SerializeMap> {
+        Ok(SerializeMap {
+            lua: self.lua,
+            key: None,
+            table: self.lua.create_table_with_capacity(0, len.unwrap_or(0))?,
+            options: self.options,
+        })
+    }
+
+    #[inline]
+    fn serialize_struct(self, name: &'static str, len: usize) -> Result<Self::SerializeStruct> {
+        if self.options.detect_serde_json_arbitrary_precision
+            && name == "$serde_json::private::Number"
+            && len == 1
+        {
+            return Ok(SerializeStruct {
+                lua: self.lua,
+                inner: None,
+                options: self.options,
+            });
+        }
+
+        Ok(SerializeStruct {
+            lua: self.lua,
+            inner: Some(Value::Table(self.lua.create_table_with_capacity(0, len)?)),
+            options: self.options,
+        })
+    }
+
+    #[inline]
+    fn serialize_struct_variant(
+        self,
+        _name: &'static str,
+        _variant_index: u32,
+        variant: &'static str,
+        len: usize,
+    ) -> Result<Self::SerializeStructVariant> {
+        Ok(SerializeStructVariant {
+            lua: self.lua,
+            variant,
+            table: self.lua.create_table_with_capacity(0, len)?,
+            options: self.options,
+        })
+    }
+}
+
+#[doc(hidden)]
+pub struct SerializeSeq<'a> {
+    lua: &'a Lua,
+    #[cfg(feature = "luau")]
+    vector: Option<crate::Vector>,
+    table: Option<Table>,
+    next: usize,
+    options: Options,
+}
+
+impl<'a> SerializeSeq<'a> {
+    fn new(lua: &'a Lua, table: Table, options: Options) -> Self {
+        Self {
+            lua,
+            #[cfg(feature = "luau")]
+            vector: None,
+            table: Some(table),
+            next: 0,
+            options,
+        }
+    }
+
+    #[cfg(feature = "luau")]
+    const fn new_vector(lua: &'a Lua, options: Options) -> Self {
+        Self {
+            lua,
+            vector: Some(crate::Vector::zero()),
+            table: None,
+            next: 0,
+            options,
+        }
+    }
+}
+
+impl ser::SerializeSeq for SerializeSeq<'_> {
+    type Ok = Value;
+    type Error = Error;
+
+    fn serialize_element<T>(&mut self, value: &T) -> Result<()>
+    where
+        T: Serialize + ?Sized,
+    {
+        let value = self.lua.to_value_with(value, self.options)?;
+        let table = self.table.as_ref().unwrap();
+        table.raw_seti(self.next + 1, value)?;
+        self.next += 1;
+        Ok(())
+    }
+
+    fn end(self) -> Result<Value> {
+        Ok(Value::Table(self.table.unwrap()))
+    }
+}
+
+impl ser::SerializeTuple for SerializeSeq<'_> {
+    type Ok = Value;
+    type Error = Error;
+
+    fn serialize_element<T>(&mut self, value: &T) -> Result<()>
+    where
+        T: Serialize + ?Sized,
+    {
+        ser::SerializeSeq::serialize_element(self, value)
+    }
+
+    fn end(self) -> Result<Value> {
+        ser::SerializeSeq::end(self)
+    }
+}
+
+impl ser::SerializeTupleStruct for SerializeSeq<'_> {
+    type Ok = Value;
+    type Error = Error;
+
+    fn serialize_field<T>(&mut self, value: &T) -> Result<()>
+    where
+        T: Serialize + ?Sized,
+    {
+        #[cfg(feature = "luau")]
+        if let Some(vector) = self.vector.as_mut() {
+            let value = self.lua.to_value_with(value, self.options)?;
+            let value = self.lua.unpack(value)?;
+            vector.0[self.next] = value;
+            self.next += 1;
+            return Ok(());
+        }
+        ser::SerializeSeq::serialize_element(self, value)
+    }
+
+    fn end(self) -> Result<Value> {
+        #[cfg(feature = "luau")]
+        if let Some(vector) = self.vector {
+            return Ok(Value::Vector(vector));
+        }
+        ser::SerializeSeq::end(self)
+    }
+}
+
+#[doc(hidden)]
+pub struct SerializeTupleVariant<'a> {
+    lua: &'a Lua,
+    variant: &'static str,
+    table: Table,
+    options: Options,
+}
+
+impl ser::SerializeTupleVariant for SerializeTupleVariant<'_> {
+    type Ok = Value;
+    type Error = Error;
+
+    fn serialize_field<T>(&mut self, value: &T) -> Result<()>
+    where
+        T: Serialize + ?Sized,
+    {
+        self.table.raw_push(self.lua.to_value_with(value, self.options)?)
+    }
+
+    fn end(self) -> Result<Value> {
+        let table = self.lua.create_table()?;
+        table.raw_set(self.variant, self.table)?;
+        Ok(Value::Table(table))
+    }
+}
+
+#[doc(hidden)]
+pub struct SerializeMap<'a> {
+    lua: &'a Lua,
+    table: Table,
+    key: Option<Value>,
+    options: Options,
+}
+
+impl ser::SerializeMap for SerializeMap<'_> {
+    type Ok = Value;
+    type Error = Error;
+
+    fn serialize_key<T>(&mut self, key: &T) -> Result<()>
+    where
+        T: Serialize + ?Sized,
+    {
+        self.key = Some(self.lua.to_value_with(key, self.options)?);
+        Ok(())
+    }
+
+    fn serialize_value<T>(&mut self, value: &T) -> Result<()>
+    where
+        T: Serialize + ?Sized,
+    {
+        let key = mlua_expect!(self.key.take(), "serialize_value called before serialize_key");
+        let value = self.lua.to_value_with(value, self.options)?;
+        self.table.raw_set(key, value)
+    }
+
+    fn end(self) -> Result<Value> {
+        Ok(Value::Table(self.table))
+    }
+}
+
+#[doc(hidden)]
+pub struct SerializeStruct<'a> {
+    lua: &'a Lua,
+    inner: Option<Value>,
+    options: Options,
+}
+
+impl ser::SerializeStruct for SerializeStruct<'_> {
+    type Ok = Value;
+    type Error = Error;
+
+    fn serialize_field<T>(&mut self, key: &'static str, value: &T) -> Result<()>
+    where
+        T: Serialize + ?Sized,
+    {
+        match self.inner {
+            Some(Value::Table(ref table)) => {
+                table.raw_set(key, self.lua.to_value_with(value, self.options)?)?;
+            }
+            None if self.options.detect_serde_json_arbitrary_precision => {
+                // A special case for `serde_json::Number` with arbitrary precision.
+                assert_eq!(key, "$serde_json::private::Number");
+                self.inner = Some(self.lua.to_value_with(value, self.options)?);
+            }
+            _ => unreachable!(),
+        }
+        Ok(())
+    }
+
+    fn end(self) -> Result<Value> {
+        match self.inner {
+            Some(table @ Value::Table(_)) => Ok(table),
+            Some(value @ Value::String(_)) if self.options.detect_serde_json_arbitrary_precision => {
+                let number_s = value.to_string()?;
+                if number_s.contains(['.', 'e', 'E']) {
+                    if let Ok(number) = number_s.parse().map(Value::Number) {
+                        return Ok(number);
+                    }
+                }
+                Ok(number_s
+                    .parse()
+                    .map(Value::Integer)
+                    .or_else(|_| number_s.parse().map(Value::Number))
+                    .unwrap_or(value))
+            }
+            _ => unreachable!(),
+        }
+    }
+}
+
+#[doc(hidden)]
+pub struct SerializeStructVariant<'a> {
+    lua: &'a Lua,
+    variant: &'static str,
+    table: Table,
+    options: Options,
+}
+
+impl ser::SerializeStructVariant for SerializeStructVariant<'_> {
+    type Ok = Value;
+    type Error = Error;
+
+    fn serialize_field<T>(&mut self, key: &'static str, value: &T) -> Result<()>
+    where
+        T: Serialize + ?Sized,
+    {
+        self.table
+            .raw_set(key, self.lua.to_value_with(value, self.options)?)?;
+        Ok(())
+    }
+
+    fn end(self) -> Result<Value> {
+        let table = self.lua.create_table_with_capacity(0, 1)?;
+        table.raw_set(self.variant, self.table)?;
+        Ok(Value::Table(table))
+    }
+}

src/state/extra.rs

@@ -0,0 +1,290 @@
+use std::any::TypeId;
+use std::cell::UnsafeCell;
+use std::mem::MaybeUninit;
+use std::os::raw::{c_int, c_void};
+use std::ptr;
+use std::rc::Rc;
+use std::sync::Arc;
+
+use parking_lot::Mutex;
+use rustc_hash::FxHashMap;
+
+use crate::error::Result;
+use crate::state::RawLua;
+use crate::stdlib::StdLib;
+use crate::types::{AppData, ReentrantMutex, XRc};
+use crate::userdata::RawUserDataRegistry;
+use crate::util::{get_internal_metatable, push_internal_userdata, TypeKey, WrappedFailure};
+
+#[cfg(any(feature = "luau", doc))]
+use crate::chunk::Compiler;
+
+#[cfg(feature = "async")]
+use {futures_util::task::noop_waker_ref, std::ptr::NonNull, std::task::Waker};
+
+use super::{Lua, WeakLua};
+
+// Unique key to store `ExtraData` in the registry
+static EXTRA_REGISTRY_KEY: u8 = 0;
+
+const WRAPPED_FAILURE_POOL_DEFAULT_CAPACITY: usize = 64;
+const REF_STACK_RESERVE: c_int = 3;
+
+/// Data associated with the Lua state.
+pub(crate) struct ExtraData {
+    pub(super) lua: MaybeUninit<Lua>,
+    pub(super) weak: MaybeUninit<WeakLua>,
+    pub(super) owned: bool,
+
+    pub(super) pending_userdata_reg: FxHashMap<TypeId, RawUserDataRegistry>,
+    pub(super) registered_userdata_t: FxHashMap<TypeId, c_int>,
+    pub(super) registered_userdata_mt: FxHashMap<*const c_void, Option<TypeId>>,
+    pub(super) last_checked_userdata_mt: (*const c_void, Option<TypeId>),
+
+    // When Lua instance dropped, setting `None` would prevent collecting `RegistryKey`s
+    pub(super) registry_unref_list: Arc<Mutex<Option<Vec<c_int>>>>,
+
+    // Containers to store arbitrary data (extensions)
+    pub(super) app_data: AppData,
+    pub(super) app_data_priv: AppData,
+
+    pub(super) safe: bool,
+    pub(super) libs: StdLib,
+    // Used in module mode
+    pub(super) skip_memory_check: bool,
+
+    // Auxiliary thread to store references
+    pub(super) ref_thread: *mut ffi::lua_State,
+    pub(super) ref_stack_size: c_int,
+    pub(super) ref_stack_top: c_int,
+    pub(super) ref_free: Vec<c_int>,
+
+    // Pool of `WrappedFailure` enums in the ref thread (as userdata)
+    pub(super) wrapped_failure_pool: Vec<c_int>,
+    pub(super) wrapped_failure_top: usize,
+    // Pool of `Thread`s (coroutines) for async execution
+    #[cfg(feature = "async")]
+    pub(super) thread_pool: Vec<crate::types::ValueRefIndex>,
+
+    // Address of `WrappedFailure` metatable
+    pub(super) wrapped_failure_mt_ptr: *const c_void,
+
+    // Waker for polling futures
+    #[cfg(feature = "async")]
+    pub(super) waker: NonNull<Waker>,
+
+    #[cfg(not(feature = "luau"))]
+    pub(super) hook_callback: Option<crate::types::HookCallback>,
+    #[cfg(not(feature = "luau"))]
+    pub(super) hook_triggers: crate::debug::HookTriggers,
+    #[cfg(feature = "lua54")]
+    pub(super) warn_callback: Option<crate::types::WarnCallback>,
+    #[cfg(feature = "luau")]
+    pub(super) interrupt_callback: Option<crate::types::InterruptCallback>,
+    #[cfg(feature = "luau")]
+    pub(super) thread_creation_callback: Option<crate::types::ThreadCreationCallback>,
+    #[cfg(feature = "luau")]
+    pub(super) thread_collection_callback: Option<crate::types::ThreadCollectionCallback>,
+
+    #[cfg(feature = "luau")]
+    pub(crate) running_gc: bool,
+    #[cfg(feature = "luau")]
+    pub(crate) sandboxed: bool,
+    #[cfg(feature = "luau")]
+    pub(super) compiler: Option<Compiler>,
+    #[cfg(feature = "luau-jit")]
+    pub(super) enable_jit: bool,
+}
+
+impl Drop for ExtraData {
+    fn drop(&mut self) {
+        unsafe {
+            if !self.owned {
+                self.lua.assume_init_drop();
+            }
+
+            self.weak.assume_init_drop();
+        }
+        *self.registry_unref_list.lock() = None;
+    }
+}
+
+static EXTRA_TYPE_KEY: u8 = 0;
+
+impl TypeKey for XRc<UnsafeCell<ExtraData>> {
+    #[inline(always)]
+    fn type_key() -> *const c_void {
+        &EXTRA_TYPE_KEY as *const u8 as *const c_void
+    }
+}
+
+impl ExtraData {
+    // Index of `error_traceback` function in auxiliary thread stack
+    #[cfg(any(feature = "lua51", feature = "luajit", feature = "luau"))]
+    pub(super) const ERROR_TRACEBACK_IDX: c_int = 1;
+
+    pub(super) unsafe fn init(state: *mut ffi::lua_State, owned: bool) -> XRc<UnsafeCell<Self>> {
+        // Create ref stack thread and place it in the registry to prevent it
+        // from being garbage collected.
+        let ref_thread = mlua_expect!(
+            protect_lua!(state, 0, 0, |state| {
+                let thread = ffi::lua_newthread(state);
+                ffi::luaL_ref(state, ffi::LUA_REGISTRYINDEX);
+                thread
+            }),
+            "Error while creating ref thread",
+        );
+
+        let wrapped_failure_mt_ptr = {
+            get_internal_metatable::<WrappedFailure>(state);
+            let ptr = ffi::lua_topointer(state, -1);
+            ffi::lua_pop(state, 1);
+            ptr
+        };
+
+        // Store `error_traceback` function on the ref stack
+        #[cfg(any(feature = "lua51", feature = "luajit", feature = "luau"))]
+        {
+            ffi::lua_pushcfunction(ref_thread, crate::util::error_traceback);
+            assert_eq!(ffi::lua_gettop(ref_thread), Self::ERROR_TRACEBACK_IDX);
+        }
+
+        #[allow(clippy::arc_with_non_send_sync)]
+        let extra = XRc::new(UnsafeCell::new(ExtraData {
+            lua: MaybeUninit::uninit(),
+            weak: MaybeUninit::uninit(),
+            owned,
+            pending_userdata_reg: FxHashMap::default(),
+            registered_userdata_t: FxHashMap::default(),
+            registered_userdata_mt: FxHashMap::default(),
+            last_checked_userdata_mt: (ptr::null(), None),
+            registry_unref_list: Arc::new(Mutex::new(Some(Vec::new()))),
+            app_data: AppData::default(),
+            app_data_priv: AppData::default(),
+            safe: false,
+            libs: StdLib::NONE,
+            skip_memory_check: false,
+            ref_thread,
+            // We need some reserved stack space to move values in and out of the ref stack.
+            ref_stack_size: ffi::LUA_MINSTACK - REF_STACK_RESERVE,
+            ref_stack_top: ffi::lua_gettop(ref_thread),
+            ref_free: Vec::new(),
+            wrapped_failure_pool: Vec::with_capacity(WRAPPED_FAILURE_POOL_DEFAULT_CAPACITY),
+            wrapped_failure_top: 0,
+            #[cfg(feature = "async")]
+            thread_pool: Vec::new(),
+            wrapped_failure_mt_ptr,
+            #[cfg(feature = "async")]
+            waker: NonNull::from(noop_waker_ref()),
+            #[cfg(not(feature = "luau"))]
+            hook_callback: None,
+            #[cfg(not(feature = "luau"))]
+            hook_triggers: Default::default(),
+            #[cfg(feature = "lua54")]
+            warn_callback: None,
+            #[cfg(feature = "luau")]
+            interrupt_callback: None,
+            #[cfg(feature = "luau")]
+            thread_creation_callback: None,
+            #[cfg(feature = "luau")]
+            thread_collection_callback: None,
+            #[cfg(feature = "luau")]
+            sandboxed: false,
+            #[cfg(feature = "luau")]
+            compiler: None,
+            #[cfg(feature = "luau-jit")]
+            enable_jit: true,
+            #[cfg(feature = "luau")]
+            running_gc: false,
+        }));
+
+        // Store it in the registry
+        mlua_expect!(Self::store(&extra, state), "Error while storing extra data");
+
+        extra
+    }
+
+    pub(super) unsafe fn set_lua(&mut self, raw: &XRc<ReentrantMutex<RawLua>>) {
+        self.lua.write(Lua {
+            raw: XRc::clone(raw),
+            collect_garbage: false,
+        });
+        self.weak.write(WeakLua(XRc::downgrade(raw)));
+    }
+
+    pub(crate) unsafe fn get(state: *mut ffi::lua_State) -> *mut Self {
+        #[cfg(feature = "luau")]
+        if cfg!(not(feature = "module")) {
+            // In the main app we can use `lua_callbacks` to access ExtraData
+            return (*ffi::lua_callbacks(state)).userdata as *mut _;
+        }
+
+        let extra_key = &EXTRA_REGISTRY_KEY as *const u8 as *const c_void;
+        if ffi::lua_rawgetp(state, ffi::LUA_REGISTRYINDEX, extra_key) != ffi::LUA_TUSERDATA {
+            // `ExtraData` can be null only when Lua state is foreign.
+            // This case in used in `Lua::try_from_ptr()`.
+            ffi::lua_pop(state, 1);
+            return ptr::null_mut();
+        }
+        let extra_ptr = ffi::lua_touserdata(state, -1) as *mut Rc<UnsafeCell<ExtraData>>;
+        ffi::lua_pop(state, 1);
+        (*extra_ptr).get()
+    }
+
+    unsafe fn store(extra: &XRc<UnsafeCell<Self>>, state: *mut ffi::lua_State) -> Result<()> {
+        #[cfg(feature = "luau")]
+        if cfg!(not(feature = "module")) {
+            (*ffi::lua_callbacks(state)).userdata = extra.get() as *mut _;
+            return Ok(());
+        }
+
+        push_internal_userdata(state, XRc::clone(extra), true)?;
+        protect_lua!(state, 1, 0, fn(state) {
+            let extra_key = &EXTRA_REGISTRY_KEY as *const u8 as *const c_void;
+            ffi::lua_rawsetp(state, ffi::LUA_REGISTRYINDEX, extra_key);
+        })
+    }
+
+    #[inline(always)]
+    pub(super) unsafe fn lua(&self) -> &Lua {
+        self.lua.assume_init_ref()
+    }
+
+    #[inline(always)]
+    pub(crate) unsafe fn raw_lua(&self) -> &RawLua {
+        &*self.lua.assume_init_ref().raw.data_ptr()
+    }
+
+    #[inline(always)]
+    pub(super) unsafe fn weak(&self) -> &WeakLua {
+        self.weak.assume_init_ref()
+    }
+
+    /// Pops a reference from top of the auxiliary stack and move it to a first free slot.
+    pub(super) unsafe fn ref_stack_pop(&mut self) -> c_int {
+        if let Some(free) = self.ref_free.pop() {
+            ffi::lua_replace(self.ref_thread, free);
+            return free;
+        }
+
+        // Try to grow max stack size
+        if self.ref_stack_top >= self.ref_stack_size {
+            let mut inc = self.ref_stack_size; // Try to double stack size
+            while inc > 0 && ffi::lua_checkstack(self.ref_thread, inc + REF_STACK_RESERVE) == 0 {
+                inc /= 2;
+            }
+            if inc == 0 {
+                // Pop item on top of the stack to avoid stack leaking and successfully run destructors
+                // during unwinding.
+                ffi::lua_pop(self.ref_thread, 1);
+                let top = self.ref_stack_top;
+                // It is a user error to create too many references to exhaust the Lua max stack size
+                // for the ref thread.
+                panic!("cannot create a Lua reference, out of auxiliary stack space (used {top} slots)");
+            }
+            self.ref_stack_size += inc;
+        }
+        self.ref_stack_top += 1;
+        self.ref_stack_top
+    }
+}

src/state/util.rs

@@ -0,0 +1,152 @@
+use std::os::raw::c_int;
+use std::panic::{catch_unwind, AssertUnwindSafe};
+use std::ptr;
+use std::sync::Arc;
+
+use crate::error::{Error, Result};
+use crate::state::{ExtraData, RawLua};
+use crate::util::{self, get_internal_metatable, WrappedFailure};
+
+struct StateGuard<'a>(&'a RawLua, *mut ffi::lua_State);
+
+impl<'a> StateGuard<'a> {
+    fn new(inner: &'a RawLua, mut state: *mut ffi::lua_State) -> Self {
+        state = inner.state.replace(state);
+        Self(inner, state)
+    }
+}
+
+impl Drop for StateGuard<'_> {
+    fn drop(&mut self) {
+        self.0.state.set(self.1);
+    }
+}
+
+// An optimized version of `callback_error` that does not allocate `WrappedFailure` userdata
+// and instead reuses unused values from previous calls (or allocates new).
+pub(crate) unsafe fn callback_error_ext<F, R>(
+    state: *mut ffi::lua_State,
+    mut extra: *mut ExtraData,
+    wrap_error: bool,
+    f: F,
+) -> R
+where
+    F: FnOnce(*mut ExtraData, c_int) -> Result<R>,
+{
+    if extra.is_null() {
+        extra = ExtraData::get(state);
+    }
+
+    let nargs = ffi::lua_gettop(state);
+
+    enum PreallocatedFailure {
+        New(*mut WrappedFailure),
+        Reserved,
+    }
+
+    impl PreallocatedFailure {
+        unsafe fn reserve(state: *mut ffi::lua_State, extra: *mut ExtraData) -> Self {
+            if (*extra).wrapped_failure_top > 0 {
+                (*extra).wrapped_failure_top -= 1;
+                return PreallocatedFailure::Reserved;
+            }
+
+            // We need to check stack for Luau in case when callback is called from interrupt
+            // See https://github.com/luau-lang/luau/issues/446 and mlua #142 and #153
+            #[cfg(feature = "luau")]
+            ffi::lua_rawcheckstack(state, 2);
+            // Place it to the beginning of the stack
+            let ud = WrappedFailure::new_userdata(state);
+            ffi::lua_insert(state, 1);
+            PreallocatedFailure::New(ud)
+        }
+
+        #[cold]
+        unsafe fn r#use(&self, state: *mut ffi::lua_State, extra: *mut ExtraData) -> *mut WrappedFailure {
+            let ref_thread = (*extra).ref_thread;
+            match *self {
+                PreallocatedFailure::New(ud) => {
+                    ffi::lua_settop(state, 1);
+                    ud
+                }
+                PreallocatedFailure::Reserved => {
+                    let index = (*extra).wrapped_failure_pool.pop().unwrap();
+                    ffi::lua_settop(state, 0);
+                    #[cfg(feature = "luau")]
+                    ffi::lua_rawcheckstack(state, 2);
+                    ffi::lua_xpush(ref_thread, state, index);
+                    ffi::lua_pushnil(ref_thread);
+                    ffi::lua_replace(ref_thread, index);
+                    (*extra).ref_free.push(index);
+                    ffi::lua_touserdata(state, -1) as *mut WrappedFailure
+                }
+            }
+        }
+
+        unsafe fn release(self, state: *mut ffi::lua_State, extra: *mut ExtraData) {
+            let ref_thread = (*extra).ref_thread;
+            match self {
+                PreallocatedFailure::New(_) => {
+                    ffi::lua_rotate(state, 1, -1);
+                    ffi::lua_xmove(state, ref_thread, 1);
+                    let index = (*extra).ref_stack_pop();
+                    (*extra).wrapped_failure_pool.push(index);
+                    (*extra).wrapped_failure_top += 1;
+                }
+                PreallocatedFailure::Reserved => (*extra).wrapped_failure_top += 1,
+            }
+        }
+    }
+
+    // We cannot shadow Rust errors with Lua ones, so we need to reserve pre-allocated memory
+    // to store a wrapped failure (error or panic) *before* we proceed.
+    let prealloc_failure = PreallocatedFailure::reserve(state, extra);
+
+    match catch_unwind(AssertUnwindSafe(|| {
+        let rawlua = (*extra).raw_lua();
+        let _guard = StateGuard::new(rawlua, state);
+        f(extra, nargs)
+    })) {
+        Ok(Ok(r)) => {
+            // Return unused `WrappedFailure` to the pool
+            prealloc_failure.release(state, extra);
+            r
+        }
+        Ok(Err(err)) => {
+            let wrapped_error = prealloc_failure.r#use(state, extra);
+
+            if !wrap_error {
+                ptr::write(wrapped_error, WrappedFailure::Error(err));
+                get_internal_metatable::<WrappedFailure>(state);
+                ffi::lua_setmetatable(state, -2);
+                ffi::lua_error(state)
+            }
+
+            // Build `CallbackError` with traceback
+            let traceback = if ffi::lua_checkstack(state, ffi::LUA_TRACEBACK_STACK) != 0 {
+                ffi::luaL_traceback(state, state, ptr::null(), 0);
+                let traceback = util::to_string(state, -1);
+                ffi::lua_pop(state, 1);
+                traceback
+            } else {
+                "<not enough stack space for traceback>".to_string()
+            };
+            let cause = Arc::new(err);
+            ptr::write(
+                wrapped_error,
+                WrappedFailure::Error(Error::CallbackError { traceback, cause }),
+            );
+            get_internal_metatable::<WrappedFailure>(state);
+            ffi::lua_setmetatable(state, -2);
+
+            ffi::lua_error(state)
+        }
+        Err(p) => {
+            let wrapped_panic = prealloc_failure.r#use(state, extra);
+            ptr::write(wrapped_panic, WrappedFailure::Panic(Some(p)));
+            get_internal_metatable::<WrappedFailure>(state);
+            ffi::lua_setmetatable(state, -2);
+            ffi::lua_error(state)
+        }
+    }
+}

src/stdlib.rs

@@ -1,31 +1,85 @@
 use std::ops::{BitAnd, BitAndAssign, BitOr, BitOrAssign, BitXor, BitXorAssign};
-use std::u32;
 
-/// Flags describing the set of lua modules to load.
+/// Flags describing the set of lua standard libraries to load.
 #[derive(Copy, Clone, Debug, Eq, Ord, PartialEq, PartialOrd)]
 pub struct StdLib(u32);
 
 impl StdLib {
-    #[cfg(any(feature = "lua53", feature = "lua52"))]
-    pub const COROUTINE: StdLib = StdLib(1 << 0);
-    pub const TABLE: StdLib = StdLib(1 << 1);
-    pub const IO: StdLib = StdLib(1 << 2);
-    pub const OS: StdLib = StdLib(1 << 3);
-    pub const STRING: StdLib = StdLib(1 << 4);
-    #[cfg(feature = "lua53")]
-    pub const UTF8: StdLib = StdLib(1 << 5);
-    #[cfg(any(feature = "lua52", feature = "luajit"))]
-    pub const BIT: StdLib = StdLib(1 << 6);
-    pub const MATH: StdLib = StdLib(1 << 7);
-    pub const PACKAGE: StdLib = StdLib(1 << 8);
-    #[cfg(feature = "luajit")]
-    pub const JIT: StdLib = StdLib(1 << 9);
-    #[cfg(feature = "luajit")]
-    pub const FFI: StdLib = StdLib(1 << 10);
-    pub const DEBUG: StdLib = StdLib(1 << 31); // always highest bit
+    /// [`coroutine`](https://www.lua.org/manual/5.4/manual.html#6.2) library
+    #[cfg(any(feature = "lua54", feature = "lua53", feature = "lua52", feature = "luau"))]
+    #[cfg_attr(
+        docsrs,
+        doc(cfg(any(feature = "lua54", feature = "lua53", feature = "lua52", feature = "luau")))
+    )]
+    pub const COROUTINE: StdLib = StdLib(1);
 
+    /// [`table`](https://www.lua.org/manual/5.4/manual.html#6.6) library
+    pub const TABLE: StdLib = StdLib(1 << 1);
+
+    /// [`io`](https://www.lua.org/manual/5.4/manual.html#6.8) library
+    #[cfg(not(feature = "luau"))]
+    #[cfg_attr(docsrs, doc(cfg(not(feature = "luau"))))]
+    pub const IO: StdLib = StdLib(1 << 2);
+
+    /// [`os`](https://www.lua.org/manual/5.4/manual.html#6.9) library
+    pub const OS: StdLib = StdLib(1 << 3);
+
+    /// [`string`](https://www.lua.org/manual/5.4/manual.html#6.4) library
+    pub const STRING: StdLib = StdLib(1 << 4);
+
+    /// [`utf8`](https://www.lua.org/manual/5.4/manual.html#6.5) library
+    #[cfg(any(feature = "lua54", feature = "lua53", feature = "luau"))]
+    #[cfg_attr(docsrs, doc(cfg(any(feature = "lua54", feature = "lua53", feature = "luau"))))]
+    pub const UTF8: StdLib = StdLib(1 << 5);
+
+    /// [`bit`](https://www.lua.org/manual/5.2/manual.html#6.7) library
+    #[cfg(any(feature = "lua52", feature = "luajit", feature = "luau", doc))]
+    #[cfg_attr(
+        docsrs,
+        doc(cfg(any(feature = "lua52", feature = "luajit", feature = "luau")))
+    )]
+    pub const BIT: StdLib = StdLib(1 << 6);
+
+    /// [`math`](https://www.lua.org/manual/5.4/manual.html#6.7) library
+    pub const MATH: StdLib = StdLib(1 << 7);
+
+    /// [`package`](https://www.lua.org/manual/5.4/manual.html#6.3) library
+    #[cfg(not(feature = "luau"))]
+    #[cfg_attr(docsrs, doc(cfg(not(feature = "luau"))))]
+    pub const PACKAGE: StdLib = StdLib(1 << 8);
+
+    /// [`buffer`](https://luau.org/library#buffer-library) library
+    #[cfg(any(feature = "luau", doc))]
+    #[cfg_attr(docsrs, doc(cfg(feature = "luau")))]
+    pub const BUFFER: StdLib = StdLib(1 << 9);
+
+    /// [`vector`](https://luau.org/library#vector-library) library
+    #[cfg(any(feature = "luau", doc))]
+    #[cfg_attr(docsrs, doc(cfg(feature = "luau")))]
+    pub const VECTOR: StdLib = StdLib(1 << 10);
+
+    /// [`jit`](http://luajit.org/ext_jit.html) library
+    #[cfg(any(feature = "luajit", doc))]
+    #[cfg_attr(docsrs, doc(cfg(feature = "luajit")))]
+    pub const JIT: StdLib = StdLib(1 << 11);
+
+    /// (**unsafe**) [`ffi`](http://luajit.org/ext_ffi.html) library
+    #[cfg(any(feature = "luajit", doc))]
+    #[cfg_attr(docsrs, doc(cfg(feature = "luajit")))]
+    pub const FFI: StdLib = StdLib(1 << 30);
+
+    /// (**unsafe**) [`debug`](https://www.lua.org/manual/5.4/manual.html#6.10) library
+    pub const DEBUG: StdLib = StdLib(1 << 31);
+
+    /// No libraries
+    pub const NONE: StdLib = StdLib(0);
+    /// (**unsafe**) All standard libraries
     pub const ALL: StdLib = StdLib(u32::MAX);
-    pub const ALL_NO_DEBUG: StdLib = StdLib((1 << 31) - 1);
+    /// The safe subset of the standard libraries
+    #[cfg(not(feature = "luau"))]
+    pub const ALL_SAFE: StdLib = StdLib((1 << 30) - 1);
+    #[cfg(feature = "luau")]
+    pub const ALL_SAFE: StdLib = StdLib(u32::MAX);
 
     pub fn contains(self, lib: Self) -> bool {
         (self & lib).0 != 0