Ruby » Ruby master

merge revision(s) 58524,58525,58526,59333,59337: [Backport #13616]

    zlib.c: zstream_expand_buffer_non_stream

    * ext/zlib/zlib.c (zstream_expand_buffer_non_stream): rename from
      zstream_expand_buffer_without_gvl() and replace duplicate code
      in zstream_expand_buffer().
    zlib.c: zstream_buffer_ungetbyte

    * ext/zlib/zlib.c (zstream_buffer_ungetbyte): simplify by using
      zstream_buffer_ungets().
    zlib.c: no buf_filled in zstream

    * ext/zlib/zlib.c (zstream): manage capacity and size of `buf`
      instead of size and separated member `buf_filled`.  reported by
      Christian Jalio (jalio) at https://hackerone.com/reports/211958
    Zlib::GzipReader#pos underflows after calling #ungetbyte or #ungetc at start of file [Bug #13616]

    patched by Andrew Haines <andrew@haines.org.nz> [ruby-core:81488]
    zlib.c: fix unnormalized Fixnum

    * ext/zlib/zlib.c (rb_gzfile_total_out): cast to long not to
      result in an unsigned long to normalized to Fixnum on LLP64
      platforms.  [ruby-core:81488]

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/branches/ruby_2_4@59807 b2dd03c8-39d4-4d8f-98ff-823fe69b080e