zlib: reduce garbage on Zlib::GzipReader#readpartial

For garbage-concious users who use the `outbuf' argument of
`readpartial' to supply a destination buffer, this provides
a drastic reduction in garbage when inflating large inputs
in a streaming fashion.

This results in a anonymous RSS reduction in the reader
similar to the reduction in the writer from r61631.

Results using the test script from r61631
<https://svn.ruby-lang.org/cgi-bin/viewvc.cgi?view=revision&revision=61631>

Before:

        writer   7.359999   0.000000   7.359999 (  7.360639)
        writer RssAnon:     4040 kB
        reader   6.346667   0.070000   6.416667 (  7.387654)
        reader RssAnon:    98272 kB

After:

        writer   7.309999   0.000000   7.309999 (  7.310651)
        writer RssAnon:	    4048 kB
        reader   6.146666   0.003333   6.149999 (  7.334868)
        reader RssAnon:	    4300 kB

* ext/zlib/zlib.c (struct read_raw_arg): new struct
  (gzfile_read_raw_partial): use read_raw_arg
  (gzfile_read_raw_rescue): ditto
  (gzfile_read_raw): accept outbuf, use read_raw_arg
  (gzfile_read_raw_ensure): accept outbuf
  (gzfile_read_header): ditto
  (gzfile_check_footer): ditto
  (gzfile_read_more): ditto
  (gzfile_read_raw_until_zero): adjust for changes
  (gzfile_fill): ditto
  (gzfile_readpartial): ditto
  (gzfile_read_all): ditto
  (gzfile_getc): ditto
  (gzfile_reader_end_run): ditto
  (gzfile_reader_get_unused): ditto
  (rb_gzreader_initialize): ditto
  (gzreader_skip_linebreaks): ditto
  (gzreader_gets): ditto
  (zlib_gunzip_run): ditto
  [ruby-core:84660] [Feature #14319]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@61665 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

0 files changed, 0 insertions, 0 deletions