This allows zlib streams to be processed without huge memory growth.
[Feature #6612]
* NEWS: ditto
* ext/zlib/zlib.c (zstream_expand_buffer): Uses rb_yield when a block
is given for streaming support. Refactored to use
zstream_expand_buffer_into to remove duplicate code.
* ext/zlib/zlib.c (zstream_expand_buffer_protect): Added wrapper
function to pass jump state back through GVL-free section to allow
zstream clean-up before terminating the ruby call.
* ext/zlib/zlib.c (zstream_expand_buffer_without_gvl): Acquire GVL to
yield processed chunk of output stream.
* ext/zlib/zlib.c (zstream_detach_buffer): When a block is given,
returns Qnil mid-stream and yields the output buffer at the end of
the stream.
* ext/zlib/extconf.rb: Update INCFLAGS to find internal.h for
rb_thread_call_with_gvl
* test/zlib/test_zlib.rb: Updated tests
git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@36349 b2dd03c8-39d4-4d8f-98ff-823fe69b080e