Release v0.11.2

* SocketStream need to check connectivity for writability.

When the stream is used for SSE server which works via chunked content
provider it's not possible to check connectivity over writability
because it's wrapped by DataSink. It could make the server stalled, when
the provider wants to only keep connection without send data and certain
amount of clients consumes entire threadpool.

* add unittest for SocketStream::is_writable()

SocketStream::is_writable() should return false if peer is disconnected.

* revise broken unittest ServerTest.ClientStop

DataSink could be unwritable if it's backed by connection based. Because
it could be disconnected by client right after enter centent provider.

Co-authored-by: Changbin Park <changbin.park@ahnlab.com>

CMakeLists.txt

@@ -176,7 +176,7 @@ if(HTTPLIB_COMPILE)
 	set_target_properties(${PROJECT_NAME}
 		PROPERTIES
 			VERSION ${${PROJECT_NAME}_VERSION}
-			SOVERSION ${${PROJECT_NAME}_VERSION_MAJOR}
+			SOVERSION "${${PROJECT_NAME}_VERSION_MAJOR}.${${PROJECT_NAME}_VERSION_MINOR}"
 	)
 else()
 	# This is for header-only.
@@ -247,13 +247,13 @@ if(HTTPLIB_COMPILE)
 	write_basic_package_version_file("${PROJECT_NAME}ConfigVersion.cmake"
 		# Example: if you find_package(httplib 0.5.4)
 		# then anything >= 0.5 and <= 1.0 is accepted
-		COMPATIBILITY SameMajorVersion
+		COMPATIBILITY SameMinorVersion
 	)
 else()
 	write_basic_package_version_file("${PROJECT_NAME}ConfigVersion.cmake"
 		# Example: if you find_package(httplib 0.5.4)
 		# then anything >= 0.5 and <= 1.0 is accepted
-		COMPATIBILITY SameMajorVersion
+		COMPATIBILITY SameMinorVersion
 		# Tells Cmake that it's a header-only lib
 		# Mildly useful for end-users :)
 		ARCH_INDEPENDENT

README.md

@@ -7,12 +7,12 @@ A C++11 single-file header-only cross platform HTTP/HTTPS library.
 
 It's extremely easy to setup. Just include the **httplib.h** file in your code!
 
-NOTE: This is a multi-threaded 'blocking' HTTP library. If you are looking for a 'non-blocking' library, this is not the one that you want.
+NOTE: This library uses 'blocking' socket I/O. If you are looking for a library with 'non-blocking' socket I/O, this is not the one that you want.
 
 Simple examples
 ---------------
 
-#### Server
+#### Server (Multi-threaded)
 
 ```c++
 #define CPPHTTPLIB_OPENSSL_SUPPORT

example/uploader.sh

@@ -1,5 +1,5 @@
 #/usr/bin/env bash
-for i in {1..10000}
+for i in {1..1000000}
 do
   echo "#### $i ####"
   curl -X POST -F image_file=@$1 http://localhost:1234/post > /dev/null

httplib.h

@@ -8,7 +8,7 @@
 #ifndef CPPHTTPLIB_HTTPLIB_H
 #define CPPHTTPLIB_HTTPLIB_H
 
-#define CPPHTTPLIB_VERSION "0.11.0"
+#define CPPHTTPLIB_VERSION "0.11.2"
 
 /*
  * Configuration
@@ -70,6 +70,10 @@
 #define CPPHTTPLIB_REDIRECT_MAX_COUNT 20
 #endif
 
+#ifndef CPPHTTPLIB_MULTIPART_FORM_DATA_FILE_MAX_COUNT
+#define CPPHTTPLIB_MULTIPART_FORM_DATA_FILE_MAX_COUNT 1024
+#endif
+
 #ifndef CPPHTTPLIB_PAYLOAD_MAX_LENGTH
 #define CPPHTTPLIB_PAYLOAD_MAX_LENGTH ((std::numeric_limits<size_t>::max)())
 #endif
@@ -183,6 +187,7 @@ using socket_t = SOCKET;
 #include <pthread.h>
 #include <sys/select.h>
 #include <sys/socket.h>
+#include <sys/un.h>
 #include <unistd.h>
 
 using socket_t = int;
@@ -948,6 +953,11 @@ public:
   Result Put(const std::string &path, const Params &params);
   Result Put(const std::string &path, const Headers &headers,
              const Params &params);
+  Result Put(const std::string &path, const MultipartFormDataItems &items);
+  Result Put(const std::string &path, const Headers &headers,
+             const MultipartFormDataItems &items);
+  Result Put(const std::string &path, const Headers &headers,
+             const MultipartFormDataItems &items, const std::string &boundary);
 
   Result Patch(const std::string &path);
   Result Patch(const std::string &path, const char *body, size_t content_length,
@@ -992,6 +1002,8 @@ public:
 
   size_t is_socket_open() const;
 
+  socket_t socket() const;
+
   void stop();
 
   void set_hostname_addr_map(std::map<std::string, std::string> addr_map);
@@ -1301,6 +1313,11 @@ public:
   Result Put(const std::string &path, const Params &params);
   Result Put(const std::string &path, const Headers &headers,
              const Params &params);
+  Result Put(const std::string &path, const MultipartFormDataItems &items);
+  Result Put(const std::string &path, const Headers &headers,
+             const MultipartFormDataItems &items);
+  Result Put(const std::string &path, const Headers &headers,
+             const MultipartFormDataItems &items, const std::string &boundary);
   Result Patch(const std::string &path);
   Result Patch(const std::string &path, const char *body, size_t content_length,
                const std::string &content_type);
@@ -1344,6 +1361,8 @@ public:
 
   size_t is_socket_open() const;
 
+  socket_t socket() const;
+
   void stop();
 
   void set_hostname_addr_map(std::map<std::string, std::string> addr_map);
@@ -2566,6 +2585,30 @@ socket_t create_socket(const std::string &host, const std::string &ip, int port,
     hints.ai_flags = socket_flags;
   }
 
+#ifndef _WIN32
+  if (hints.ai_family == AF_UNIX) {
+    const auto addrlen = host.length();
+    if (addrlen > sizeof(sockaddr_un::sun_path)) return INVALID_SOCKET;
+
+    auto sock = socket(hints.ai_family, hints.ai_socktype, hints.ai_protocol);
+    if (sock != INVALID_SOCKET) {
+      sockaddr_un addr;
+      addr.sun_family = AF_UNIX;
+      std::copy(host.begin(), host.end(), addr.sun_path);
+
+      hints.ai_addr = reinterpret_cast<sockaddr *>(&addr);
+      hints.ai_addrlen = static_cast<socklen_t>(
+          sizeof(addr) - sizeof(addr.sun_path) + addrlen);
+
+      if (!bind_or_connect(sock, hints)) {
+        close_socket(sock);
+        sock = INVALID_SOCKET;
+      }
+    }
+    return sock;
+  }
+#endif
+
   auto service = std::to_string(port);
 
   if (getaddrinfo(node, service.c_str(), &hints, &result)) {
@@ -3797,7 +3840,11 @@ class MultipartFormDataParser {
 public:
   MultipartFormDataParser() = default;
 
-  void set_boundary(std::string &&boundary) { boundary_ = boundary; }
+  void set_boundary(std::string &&boundary) {
+    boundary_ = boundary;
+    dash_boundary_crlf_ = dash_ + boundary_ + crlf_;
+    crlf_dash_boundary_ = crlf_ + dash_ + boundary_;
+  }
 
   bool is_valid() const { return is_valid_; }
 
@@ -3809,19 +3856,15 @@ public:
         R"~(^Content-Disposition:\s*form-data;\s*name="(.*?)"(?:;\s*filename="(.*?)")?(?:;\s*filename\*=\S+)?\s*$)~",
         std::regex_constants::icase);
 
-    static const std::string dash_ = "--";
-    static const std::string crlf_ = "\r\n";
-
     buf_append(buf, n);
 
     while (buf_size() > 0) {
       switch (state_) {
       case 0: { // Initial boundary
-        auto pattern = dash_ + boundary_ + crlf_;
-        buf_erase(buf_find(pattern));
-        if (pattern.size() > buf_size()) { return true; }
-        if (!buf_start_with(pattern)) { return false; }
-        buf_erase(pattern.size());
+        buf_erase(buf_find(dash_boundary_crlf_));
+        if (dash_boundary_crlf_.size() > buf_size()) { return true; }
+        if (!buf_start_with(dash_boundary_crlf_)) { return false; }
+        buf_erase(dash_boundary_crlf_.size());
         state_ = 1;
         break;
       }
@@ -3856,7 +3899,6 @@ public:
               file_.filename = m[2];
             }
           }
-
           buf_erase(pos + crlf_.size());
           pos = buf_find(crlf_);
         }
@@ -3864,40 +3906,25 @@ public:
         break;
       }
       case 3: { // Body
-        {
-          auto pattern = crlf_ + dash_;
-          if (pattern.size() > buf_size()) { return true; }
-
-          auto pos = buf_find(pattern);
-
+        if (crlf_dash_boundary_.size() > buf_size()) { return true; }
+        auto pos = buf_find(crlf_dash_boundary_);
+        if (pos < buf_size()) {
           if (!content_callback(buf_data(), pos)) {
             is_valid_ = false;
             return false;
           }
-
-          buf_erase(pos);
-        }
-        {
-          auto pattern = crlf_ + dash_ + boundary_;
-          if (pattern.size() > buf_size()) { return true; }
-
-          auto pos = buf_find(pattern);
-          if (pos < buf_size()) {
-            if (!content_callback(buf_data(), pos)) {
+          buf_erase(pos + crlf_dash_boundary_.size());
+          state_ = 4;
+        } else {
+          auto len = buf_size() - crlf_dash_boundary_.size();
+          if (len > 0) {
+            if (!content_callback(buf_data(), len)) {
               is_valid_ = false;
               return false;
             }
-
-            buf_erase(pos + pattern.size());
-            state_ = 4;
-          } else {
-            if (!content_callback(buf_data(), pattern.size())) {
-              is_valid_ = false;
-              return false;
-            }
-
-            buf_erase(pattern.size());
+            buf_erase(len);
           }
+          return true;
         }
         break;
       }
@@ -3907,10 +3934,9 @@ public:
           buf_erase(crlf_.size());
           state_ = 1;
         } else {
-          auto pattern = dash_ + crlf_;
-          if (pattern.size() > buf_size()) { return true; }
-          if (buf_start_with(pattern)) {
-            buf_erase(pattern.size());
+          if (dash_crlf_.size() > buf_size()) { return true; }
+          if (buf_start_with(dash_crlf_)) {
+            buf_erase(dash_crlf_.size());
             is_valid_ = true;
             buf_erase(buf_size()); // Remove epilogue
           } else {
@@ -3941,7 +3967,12 @@ private:
     return true;
   }
 
+  const std::string dash_ = "--";
+  const std::string crlf_ = "\r\n";
+  const std::string dash_crlf_ = "--\r\n";
   std::string boundary_;
+  std::string dash_boundary_crlf_;
+  std::string crlf_dash_boundary_;
 
   size_t state_ = 0;
   bool is_valid_ = false;
@@ -4047,6 +4078,44 @@ inline std::string make_multipart_data_boundary() {
   return result;
 }
 
+inline bool is_multipart_boundary_chars_valid(const std::string &boundary) {
+  auto valid = true;
+  for (size_t i = 0; i < boundary.size(); i++) {
+    auto c = boundary[i];
+    if (!std::isalnum(c) && c != '-' && c != '_') {
+      valid = false;
+      break;
+    }
+  }
+  return valid;
+}
+
+inline std::string
+serialize_multipart_formdata(const MultipartFormDataItems &items,
+                             const std::string &boundary,
+                             std::string &content_type) {
+  std::string body;
+
+  for (const auto &item : items) {
+    body += "--" + boundary + "\r\n";
+    body += "Content-Disposition: form-data; name=\"" + item.name + "\"";
+    if (!item.filename.empty()) {
+      body += "; filename=\"" + item.filename + "\"";
+    }
+    body += "\r\n";
+    if (!item.content_type.empty()) {
+      body += "Content-Type: " + item.content_type + "\r\n";
+    }
+    body += "\r\n";
+    body += item.content + "\r\n";
+  }
+
+  body += "--" + boundary + "--\r\n";
+
+  content_type = "multipart/form-data; boundary=" + boundary;
+  return body;
+}
+
 inline std::pair<size_t, size_t>
 get_range_offset_and_length(const Request &req, size_t content_length,
                             size_t index) {
@@ -4653,7 +4722,8 @@ inline bool SocketStream::is_readable() const {
 }
 
 inline bool SocketStream::is_writable() const {
-  return select_write(sock_, write_timeout_sec_, write_timeout_usec_) > 0;
+  return select_write(sock_, write_timeout_sec_, write_timeout_usec_) > 0 &&
+    is_socket_alive(sock_);
 }
 
 inline ssize_t SocketStream::read(char *ptr, size_t size) {
@@ -5190,6 +5260,7 @@ Server::write_content_with_provider(Stream &strm, const Request &req,
 
 inline bool Server::read_content(Stream &strm, Request &req, Response &res) {
   MultipartFormDataMap::iterator cur;
+  auto file_count = 0;
   if (read_content_core(
           strm, req, res,
           // Regular
@@ -5200,6 +5271,9 @@ inline bool Server::read_content(Stream &strm, Request &req, Response &res) {
           },
           // Multipart
           [&](const MultipartFormData &file) {
+            if (file_count++ == CPPHTTPLIB_MULTIPART_FORM_DATA_FILE_MAX_COUNT) {
+              return false;
+            }
             cur = req.files.emplace(file.name, file);
             return true;
           },
@@ -6728,37 +6802,22 @@ inline Result ClientImpl::Post(const std::string &path,
 
 inline Result ClientImpl::Post(const std::string &path, const Headers &headers,
                                const MultipartFormDataItems &items) {
-  return Post(path, headers, items, detail::make_multipart_data_boundary());
+  std::string content_type;
+  const auto &body = detail::serialize_multipart_formdata(
+      items, detail::make_multipart_data_boundary(), content_type);
+  return Post(path, headers, body, content_type.c_str());
 }
+
 inline Result ClientImpl::Post(const std::string &path, const Headers &headers,
                                const MultipartFormDataItems &items,
                                const std::string &boundary) {
-  for (size_t i = 0; i < boundary.size(); i++) {
-    char c = boundary[i];
-    if (!std::isalnum(c) && c != '-' && c != '_') {
-      return Result{nullptr, Error::UnsupportedMultipartBoundaryChars};
-    }
+  if (!detail::is_multipart_boundary_chars_valid(boundary)) {
+    return Result{nullptr, Error::UnsupportedMultipartBoundaryChars};
   }
 
-  std::string body;
-
-  for (const auto &item : items) {
-    body += "--" + boundary + "\r\n";
-    body += "Content-Disposition: form-data; name=\"" + item.name + "\"";
-    if (!item.filename.empty()) {
-      body += "; filename=\"" + item.filename + "\"";
-    }
-    body += "\r\n";
-    if (!item.content_type.empty()) {
-      body += "Content-Type: " + item.content_type + "\r\n";
-    }
-    body += "\r\n";
-    body += item.content + "\r\n";
-  }
-
-  body += "--" + boundary + "--\r\n";
-
-  std::string content_type = "multipart/form-data; boundary=" + boundary;
+  std::string content_type;
+  const auto &body =
+      detail::serialize_multipart_formdata(items, boundary, content_type);
   return Post(path, headers, body, content_type.c_str());
 }
 
@@ -6831,6 +6890,32 @@ inline Result ClientImpl::Put(const std::string &path, const Headers &headers,
   return Put(path, headers, query, "application/x-www-form-urlencoded");
 }
 
+inline Result ClientImpl::Put(const std::string &path,
+                              const MultipartFormDataItems &items) {
+  return Put(path, Headers(), items);
+}
+
+inline Result ClientImpl::Put(const std::string &path, const Headers &headers,
+                              const MultipartFormDataItems &items) {
+  std::string content_type;
+  const auto &body = detail::serialize_multipart_formdata(
+      items, detail::make_multipart_data_boundary(), content_type);
+  return Put(path, headers, body, content_type);
+}
+
+inline Result ClientImpl::Put(const std::string &path, const Headers &headers,
+                              const MultipartFormDataItems &items,
+                              const std::string &boundary) {
+  if (!detail::is_multipart_boundary_chars_valid(boundary)) {
+    return Result{nullptr, Error::UnsupportedMultipartBoundaryChars};
+  }
+
+  std::string content_type;
+  const auto &body =
+      detail::serialize_multipart_formdata(items, boundary, content_type);
+  return Put(path, headers, body, content_type);
+}
+
 inline Result ClientImpl::Patch(const std::string &path) {
   return Patch(path, std::string(), std::string());
 }
@@ -6956,6 +7041,8 @@ inline size_t ClientImpl::is_socket_open() const {
   return socket_.is_open();
 }
 
+inline socket_t ClientImpl::socket() const { return socket_.sock; }
+
 inline void ClientImpl::stop() {
   std::lock_guard<std::mutex> guard(socket_mutex_);
 
@@ -7259,8 +7346,8 @@ inline bool SSLSocketStream::is_readable() const {
 }
 
 inline bool SSLSocketStream::is_writable() const {
-  return detail::select_write(sock_, write_timeout_sec_, write_timeout_usec_) >
-         0;
+  return select_write(sock_, write_timeout_sec_, write_timeout_usec_) > 0 &&
+    is_socket_alive(sock_);
 }
 
 inline ssize_t SSLSocketStream::read(char *ptr, size_t size) {
@@ -7862,13 +7949,13 @@ inline Client::Client(const std::string &scheme_host_port,
 
     if (is_ssl) {
 #ifdef CPPHTTPLIB_OPENSSL_SUPPORT
-      cli_ = detail::make_unique<SSLClient>(host.c_str(), port,
-                                            client_cert_path, client_key_path);
+      cli_ = detail::make_unique<SSLClient>(host, port, client_cert_path,
+                                            client_key_path);
       is_ssl_ = is_ssl;
 #endif
     } else {
-      cli_ = detail::make_unique<ClientImpl>(host.c_str(), port,
-                                             client_cert_path, client_key_path);
+      cli_ = detail::make_unique<ClientImpl>(host, port, client_cert_path,
+                                             client_key_path);
     }
   } else {
     cli_ = detail::make_unique<ClientImpl>(scheme_host_port, 80,
@@ -8078,6 +8165,19 @@ inline Result Client::Put(const std::string &path, const Headers &headers,
                           const Params &params) {
   return cli_->Put(path, headers, params);
 }
+inline Result Client::Put(const std::string &path,
+                          const MultipartFormDataItems &items) {
+  return cli_->Put(path, items);
+}
+inline Result Client::Put(const std::string &path, const Headers &headers,
+                          const MultipartFormDataItems &items) {
+  return cli_->Put(path, headers, items);
+}
+inline Result Client::Put(const std::string &path, const Headers &headers,
+                          const MultipartFormDataItems &items,
+                          const std::string &boundary) {
+  return cli_->Put(path, headers, items, boundary);
+}
 inline Result Client::Patch(const std::string &path) {
   return cli_->Patch(path);
 }
@@ -8163,6 +8263,8 @@ inline Result Client::send(const Request &req) { return cli_->send(req); }
 
 inline size_t Client::is_socket_open() const { return cli_->is_socket_open(); }
 
+inline socket_t Client::socket() const { return cli_->socket(); }
+
 inline void Client::stop() { cli_->stop(); }
 
 inline void

meson.build

@@ -77,6 +77,7 @@ if get_option('cpp-httplib_compile')
     dependencies: deps,
     cpp_args: args,
     version: version,
+    soversion: version.split('.')[0] + '.' + version.split('.')[1],
     install: true
   )
   cpp_httplib_dep = declare_dependency(compile_args: args, dependencies: deps, link_with: lib, sources: httplib_ch[1])

test/test.cc

@@ -1643,7 +1643,8 @@ protected:
                res.set_content_provider(
                    size_t(-1), "text/plain",
                    [](size_t /*offset*/, size_t /*length*/, DataSink &sink) {
-                     EXPECT_TRUE(sink.is_writable());
+                     if (!sink.is_writable()) return false;
+
                      sink.os << "data_chunk";
                      return true;
                    });
@@ -4750,6 +4751,43 @@ TEST(SendAPI, SimpleInterface_Online) {
   EXPECT_EQ(301, res->status);
 }
 
+TEST(ClientImplMethods, GetSocketTest) {
+  httplib::Server svr;
+  svr.Get( "/", [&](const httplib::Request& /*req*/, httplib::Response& res) {
+    res.status = 200;
+  });
+
+  auto thread = std::thread([&]() { svr.listen("127.0.0.1", 3333); });
+
+  while (!svr.is_running()) {
+    std::this_thread::sleep_for(std::chrono::milliseconds(5));
+  }
+
+  {
+    httplib::Client cli("http://127.0.0.1:3333");
+    cli.set_keep_alive(true);
+
+    // Use the behavior of cpp-httplib of opening the connection
+    // only when the first request happens. If that changes,
+    // this test would be obsolete.
+
+    EXPECT_EQ(cli.socket(), INVALID_SOCKET);
+
+    // This also implicitly tests the server. But other tests would fail much
+    // earlier than this one to be considered.
+
+    auto res = cli.Get("/");
+    ASSERT_TRUE(res);
+
+    EXPECT_EQ(200, res->status);
+    ASSERT_TRUE(cli.socket() != INVALID_SOCKET);
+  }
+
+  svr.stop();
+  thread.join();
+  ASSERT_FALSE(svr.is_running());
+}
+
 // Disabled due to out-of-memory problem on GitHub Actions
 #ifdef _WIN64
 TEST(ServerLargeContentTest, DISABLED_SendLargeContent) {
@@ -5025,5 +5063,370 @@ TEST(MultipartFormDataTest, WithPreamble) {
   t.join();
 }
 
+TEST(MultipartFormDataTest, PostCustomBoundary) {
+  SSLServer svr(SERVER_CERT_FILE, SERVER_PRIVATE_KEY_FILE);
+
+  svr.Post("/post_customboundary", [&](const Request &req, Response & /*res*/,
+                        const ContentReader &content_reader) {
+    if (req.is_multipart_form_data()) {
+      MultipartFormDataItems files;
+      content_reader(
+          [&](const MultipartFormData &file) {
+            files.push_back(file);
+            return true;
+          },
+          [&](const char *data, size_t data_length) {
+            files.back().content.append(data, data_length);
+            return true;
+          });
+
+      EXPECT_TRUE(std::string(files[0].name) == "document");
+      EXPECT_EQ(size_t(1024 * 1024 * 2), files[0].content.size());
+      EXPECT_TRUE(files[0].filename == "2MB_data");
+      EXPECT_TRUE(files[0].content_type == "application/octet-stream");
+
+      EXPECT_TRUE(files[1].name == "hello");
+      EXPECT_TRUE(files[1].content == "world");
+      EXPECT_TRUE(files[1].filename == "");
+      EXPECT_TRUE(files[1].content_type == "");
+    } else {
+      std::string body;
+      content_reader([&](const char *data, size_t data_length) {
+        body.append(data, data_length);
+        return true;
+      });
+    }
+  });
+
+  auto t = std::thread([&]() { svr.listen("localhost", 8080); });
+  while (!svr.is_running()) {
+    std::this_thread::sleep_for(std::chrono::milliseconds(1));
+  }
+  std::this_thread::sleep_for(std::chrono::seconds(1));
+
+  {
+    std::string data(1024 * 1024 * 2, '.');
+    std::stringstream buffer;
+    buffer << data;
+
+    Client cli("https://localhost:8080");
+    cli.enable_server_certificate_verification(false);
+
+    MultipartFormDataItems items{
+        {"document", buffer.str(), "2MB_data", "application/octet-stream"},
+        {"hello", "world", "", ""},
+    };
+
+    auto res = cli.Post("/post_customboundary", {}, items, "abc-abc");
+    ASSERT_TRUE(res);
+    ASSERT_EQ(200, res->status);
+  }
+
+  svr.stop();
+  t.join();
+}
+
+TEST(MultipartFormDataTest, PostInvalidBoundaryChars) {
+  
+  std::this_thread::sleep_for(std::chrono::seconds(1));
+
+  std::string data(1024 * 1024 * 2, '&');
+  std::stringstream buffer;
+  buffer << data;
+
+  Client cli("https://localhost:8080");
+
+  MultipartFormDataItems items{
+      {"document", buffer.str(), "2MB_data", "application/octet-stream"},
+      {"hello", "world", "", ""},
+  };
+
+  for (const char& c: " \t\r\n") {
+    auto res = cli.Post("/invalid_boundary", {}, items, string("abc123").append(1, c));
+    ASSERT_EQ(Error::UnsupportedMultipartBoundaryChars, res.error());
+    ASSERT_FALSE(res);
+  }
+
+}
+
+TEST(MultipartFormDataTest, PutFormData) {
+  SSLServer svr(SERVER_CERT_FILE, SERVER_PRIVATE_KEY_FILE);
+
+  svr.Put("/put", [&](const Request &req, const Response & /*res*/,
+                      const ContentReader &content_reader) {
+    if (req.is_multipart_form_data()) {
+      MultipartFormDataItems files;
+      content_reader(
+          [&](const MultipartFormData &file) {
+            files.push_back(file);
+            return true;
+          },
+          [&](const char *data, size_t data_length) {
+            files.back().content.append(data, data_length);
+            return true;
+          });
+
+      EXPECT_TRUE(std::string(files[0].name) == "document");
+      EXPECT_EQ(size_t(1024 * 1024 * 2), files[0].content.size());
+      EXPECT_TRUE(files[0].filename == "2MB_data");
+      EXPECT_TRUE(files[0].content_type == "application/octet-stream");
+
+      EXPECT_TRUE(files[1].name == "hello");
+      EXPECT_TRUE(files[1].content == "world");
+      EXPECT_TRUE(files[1].filename == "");
+      EXPECT_TRUE(files[1].content_type == "");
+    } else {
+      std::string body;
+      content_reader([&](const char *data, size_t data_length) {
+        body.append(data, data_length);
+        return true;
+      });
+    }
+  });
+
+  auto t = std::thread([&]() { svr.listen("localhost", 8080); });
+  while (!svr.is_running()) {
+    std::this_thread::sleep_for(std::chrono::milliseconds(1));
+  }
+  std::this_thread::sleep_for(std::chrono::seconds(1));
+
+  {
+    std::string data(1024 * 1024 * 2, '&');
+    std::stringstream buffer;
+    buffer << data;
+
+    Client cli("https://localhost:8080");
+    cli.enable_server_certificate_verification(false);
+
+    MultipartFormDataItems items{
+        {"document", buffer.str(), "2MB_data", "application/octet-stream"},
+        {"hello", "world", "", ""},
+    };
+
+    auto res = cli.Put("/put", items);
+    ASSERT_TRUE(res);
+    ASSERT_EQ(200, res->status);
+  }
+
+  svr.stop();
+  t.join();
+}
+
+TEST(MultipartFormDataTest, PutFormDataCustomBoundary) {
+  SSLServer svr(SERVER_CERT_FILE, SERVER_PRIVATE_KEY_FILE);
+
+  svr.Put("/put_customboundary", [&](const Request &req, const Response & /*res*/,
+                      const ContentReader &content_reader) {
+    if (req.is_multipart_form_data()) {
+      MultipartFormDataItems files;
+      content_reader(
+          [&](const MultipartFormData &file) {
+            files.push_back(file);
+            return true;
+          },
+          [&](const char *data, size_t data_length) {
+            files.back().content.append(data, data_length);
+            return true;
+          });
+
+      EXPECT_TRUE(std::string(files[0].name) == "document");
+      EXPECT_EQ(size_t(1024 * 1024 * 2), files[0].content.size());
+      EXPECT_TRUE(files[0].filename == "2MB_data");
+      EXPECT_TRUE(files[0].content_type == "application/octet-stream");
+
+      EXPECT_TRUE(files[1].name == "hello");
+      EXPECT_TRUE(files[1].content == "world");
+      EXPECT_TRUE(files[1].filename == "");
+      EXPECT_TRUE(files[1].content_type == "");
+    } else {
+      std::string body;
+      content_reader([&](const char *data, size_t data_length) {
+        body.append(data, data_length);
+        return true;
+      });
+    }
+  });
+
+  auto t = std::thread([&]() { svr.listen("localhost", 8080); });
+  while (!svr.is_running()) {
+    std::this_thread::sleep_for(std::chrono::milliseconds(1));
+  }
+  std::this_thread::sleep_for(std::chrono::seconds(1));
+
+  {
+    std::string data(1024 * 1024 * 2, '&');
+    std::stringstream buffer;
+    buffer << data;
+
+    Client cli("https://localhost:8080");
+    cli.enable_server_certificate_verification(false);
+
+    MultipartFormDataItems items{
+        {"document", buffer.str(), "2MB_data", "application/octet-stream"},
+        {"hello", "world", "", ""},
+    };
+
+    auto res = cli.Put("/put_customboundary", {}, items, "abc-abc_");
+    ASSERT_TRUE(res);
+    ASSERT_EQ(200, res->status);
+  }
+
+  svr.stop();
+  t.join();
+}
+
+TEST(MultipartFormDataTest, PutInvalidBoundaryChars) {
+
+  std::this_thread::sleep_for(std::chrono::seconds(1));
+
+  std::string data(1024 * 1024 * 2, '&');
+  std::stringstream buffer;
+  buffer << data;
+
+  Client cli("https://localhost:8080");
+  cli.enable_server_certificate_verification(false);
+
+  MultipartFormDataItems items{
+      {"document", buffer.str(), "2MB_data", "application/octet-stream"},
+      {"hello", "world", "", ""},
+  };
+
+  for (const char& c: " \t\r\n") {
+    auto res = cli.Put("/put", {}, items, string("abc123").append(1, c));
+    ASSERT_EQ(Error::UnsupportedMultipartBoundaryChars, res.error());
+    ASSERT_FALSE(res);
+  }
+}
+
 #endif
 
+#ifndef _WIN32
+class UnixSocketTest : public ::testing::Test {
+protected:
+  void TearDown() override {
+    std::remove(pathname_.c_str());
+  }
+
+  void client_GET(const std::string &addr) {
+    httplib::Client cli{addr};
+    cli.set_address_family(AF_UNIX);
+    ASSERT_TRUE(cli.is_valid());
+
+    const auto &result = cli.Get(pattern_);
+    ASSERT_TRUE(result) << "error: " << result.error();
+
+    const auto &resp = result.value();
+    EXPECT_EQ(resp.status, 200);
+    EXPECT_EQ(resp.body, content_);
+  }
+
+  const std::string pathname_ {"./httplib-server.sock"};
+  const std::string pattern_ {"/hi"};
+  const std::string content_ {"Hello World!"};
+};
+
+TEST_F(UnixSocketTest, pathname) {
+  httplib::Server svr;
+  svr.Get(pattern_, [&](const httplib::Request &, httplib::Response &res) {
+    res.set_content(content_, "text/plain");
+  });
+
+  std::thread t {[&] {
+    ASSERT_TRUE(svr.set_address_family(AF_UNIX).listen(pathname_, 80)); }};
+  while (!svr.is_running()) {
+    std::this_thread::sleep_for(std::chrono::milliseconds(1));
+  }
+  ASSERT_TRUE(svr.is_running());
+
+  client_GET(pathname_);
+
+  svr.stop();
+  t.join();
+}
+
+#ifdef __linux__
+TEST_F(UnixSocketTest, abstract) {
+  constexpr char svr_path[] {"\x00httplib-server.sock"};
+  const std::string abstract_addr {svr_path, sizeof(svr_path) - 1};
+
+  httplib::Server svr;
+  svr.Get(pattern_, [&](const httplib::Request &, httplib::Response &res) {
+    res.set_content(content_, "text/plain");
+  });
+
+  std::thread t {[&] {
+    ASSERT_TRUE(svr.set_address_family(AF_UNIX).listen(abstract_addr, 80)); }};
+  while (!svr.is_running()) {
+    std::this_thread::sleep_for(std::chrono::milliseconds(1));
+  }
+  ASSERT_TRUE(svr.is_running());
+
+  client_GET(abstract_addr);
+
+  svr.stop();
+  t.join();
+}
+#endif
+
+TEST(SocketStream, is_writable_UNIX) {
+  int fd[2];
+  ASSERT_EQ(0, socketpair(AF_UNIX, SOCK_STREAM, 0, fd));
+
+  const auto asSocketStream =
+    [&] (socket_t fd, std::function<bool(Stream &)> func) {
+      return detail::process_client_socket(fd, 0, 0, 0, 0, func);
+    };
+  asSocketStream(fd[0], [&] (Stream &s0) {
+    EXPECT_EQ(s0.socket(), fd[0]);
+    EXPECT_TRUE(s0.is_writable());
+
+    EXPECT_EQ(0, close(fd[1]));
+    EXPECT_FALSE(s0.is_writable());
+
+    return true;
+  });
+  EXPECT_EQ(0, close(fd[0]));
+}
+
+TEST(SocketStream, is_writable_INET) {
+  sockaddr_in addr;
+  memset(&addr, 0, sizeof(addr));
+  addr.sin_family = AF_INET;
+  addr.sin_port = htons(PORT+1);
+  addr.sin_addr.s_addr = htonl(INADDR_LOOPBACK);
+
+  int disconnected_svr_sock = -1;
+  std::thread svr {[&] {
+    const int s = socket(AF_INET, SOCK_STREAM, 0);
+    ASSERT_LE(0, s);
+    ASSERT_EQ(0, ::bind(s, reinterpret_cast<sockaddr*>(&addr), sizeof(addr)));
+    ASSERT_EQ(0, listen(s, 1));
+    ASSERT_LE(0, disconnected_svr_sock = accept(s, nullptr, nullptr));
+    ASSERT_EQ(0, close(s));
+  }};
+  std::this_thread::sleep_for(std::chrono::milliseconds(100));
+
+  std::thread cli {[&] {
+    const int s = socket(AF_INET, SOCK_STREAM, 0);
+    ASSERT_LE(0, s);
+    ASSERT_EQ(0, connect(s, reinterpret_cast<sockaddr*>(&addr), sizeof(addr)));
+    ASSERT_EQ(0, close(s));
+  }};
+  cli.join();
+  svr.join();
+  ASSERT_NE(disconnected_svr_sock, -1);
+
+  const auto asSocketStream =
+    [&] (socket_t fd, std::function<bool(Stream &)> func) {
+      return detail::process_client_socket(fd, 0, 0, 0, 0, func);
+    };
+  asSocketStream(disconnected_svr_sock, [&] (Stream &ss) {
+    EXPECT_EQ(ss.socket(), disconnected_svr_sock);
+    EXPECT_FALSE(ss.is_writable());
+
+    return true;
+  });
+
+  ASSERT_EQ(0, close(disconnected_svr_sock));
+}
+#endif  // #ifndef _WIN32