If `Class#allocate` is prohibited, subclasses should also be implicitly prohibited.
```ruby
p Class.new(Struct).allocate.class
# => #<Class:0x82362ac00> by #6122
# => allocator undefined for #<Class:0x000000083a983220> (TypeError) by Ruby 3.2
```
Added `MRB_DEFINE_ALLOCATOR()` to allow subclasses to use `Class#allocate`.
Supplement to #6122.
The method introduced by #5979 causes a fault by swapping classes.
```console
% bin/mruby -e 'Method = Proc; p Object.method(:inspect)'
zsh: segmentation fault (core dumped) bin/mruby -e 'Method = Proc; p Object.method(:inspect)'
```
After applying this patch, a `TypeError` exception will be raised.
```console
% bin/mruby -e 'Method = Proc; p Object.method(:inspect)'
trace (most recent call last):
[1] -e:1
-e:1:in method: allocation failure of Proc (TypeError)
```
However, if the `mrb_vtype` is the same object, the same care must still be taken as before.
```console
% bin/mruby -e 'Method = Binding; p method(:puts).eval("12345")'
trace (most recent call last):
[1] -e:1
-e:1:in eval: wrong argument type nil (expected Proc) (TypeError)
```
Now all functions with `io_buf` takes `mrb_io_buf` as an argument.
Renamed functions (old names):
- io_init_buf (io_buf_init)
- io_fill_buf (io_buf_fill)
- io_fill_buf_comp (io_buf_fill_comp) for UTF-8 encoding
If `outbuf` is `nil` we allocate a buffer string, if `outbuf` is a
string, we resize it to zero length. In the function `io_read`, this
condition is done twice, so we refactor out to `io_reset_outbuf()`.
I hit the following two problems.
- `io.read(0, buf)` always returned a new empty string object.
- `io.read(num, buf)` was appending data to the given `buf`.
This also meant that `buf` was never empty if EOF was reached.
We count `Proc` upper links then check for upper bounds (default:20),
but now we raise an exception as soon as the count exceeds the limit so
that we can avoid traverse unnecessary upper links.
Since Fiber#to_s did not include location information before #6105,
when location information cannot be retrieved for terminated fibers,
instead of meaningless information such as "(unknown):0", we omit
positional information altogether for terminated fibers; ref #6111
When fiber is terminated, the pointer indicated by `f->cxt->cibase->proc` is not protected from GC.
I should have done this patch way as of commit 9af6264d6b (#6105).
Since `cxt->ci` points to the last active callinfo, `cxt->ci == cxt->cibase`
does not mean it does not have correct `proc` information, so we have
removed the `f->cxt->ci > f->cxt->cibase` check. Instead, just in case
`proc` does not have `irep` information, we try to confirm `proc` does not
point to `CFUNC` nor is not an alias.
It is now possible to specify return destination directly.
This allows callinfo to distinguish between calls to the same proc object.
At the same time, the `Kernel#catch` method is adjusted.
By removing the previously required double lambda object, the REnv object is no longer created as well.
When a fiber switched by `Fiber.yield` is resumed by `Fiber#resume` by C, it is necessary to pop CI with `fiber_switch()`.
Previously, CI misalignment caused inconsistencies, including crashes, on the next `Fiber#resume`.
If `mrb_fiber_resume()` was called from a C function as a method definition, the mruby VM was not processed afterwards.
Called Fiber.yield
mrb_vm_exec() <<-- returns from the function by CINFO_RESUMED
fiber_switch() <<-- this patch causes the value to return to its pre-call state
mrb_fiber_resume()
mrb_vm_exec() <<-- previously, returns from the function immediately as it was CINFO_RESUMED
...
main()
The main objective is to make sure that fiber can be handled from C.
Also, add a mechanism to detect that the mruby VM has stopped in the middle of the process.
If it stops halfway, the test will be terminated with `abort()`.
If the filename and line number cannot be obtained, "(unknown):1" is used instead.
Also, the file name information of the terminated fiber cannot be retrieved and will be replaced as well.
This limitation is due to the fact that `cibase->proc` of the terminated fiber is collected by the GC.
```console
% bin/mruby -e 'p Fiber.new { p Fiber.current }.resume'
#<Fiber:0x82423bef0 -e:1 (resumed)>
#<Fiber:0x82423bef0 (unknown):1 (terminated)>
```
The last commit changed the behavior of aliases, and we no longer keep
the alias name symbol but the original name. Since this is a small
incompatibility from CRuby and it requires some memory to fix this, we
keep this issue right now.
Yukihiro "Matz" Matsumoto