Revert r35370 due to bad source branch

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@35372 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 14 insertions, 18 deletions

diff --git a/lib/rubygems/package/tar_input.rb b/lib/rubygems/package/tar_input.rb
index 77b4d698da..5ac93ff336 100644
--- a/lib/rubygems/package/tar_input.rb
+++ b/lib/rubygems/package/tar_input.rb
@@ -210,25 +210,21 @@ class Gem::Package::TarInput
   # the unpacking speed) we threw our hands in the air and declared that
   # this method would use the String IO approach on all platforms at all
   # times.  And that's the way it is.
-  #
-  # Revisited.  Here's the beginning of the long story.
-  # http://osdir.com/ml/lang.ruby.gems.devel/2007-06/msg00045.html
-  #
-  # StringIO wraping has never worked as a workaround by definition.  Skipping
-  # initial 10 bytes and passing -MAX_WBITS to Zlib::Inflate luckily works as
-  # gzip reader, but it only works if the GZip header is 10 bytes long (see
-  # below) and it does not check inflated stream consistency (CRC value in the
-  # Gzip trailer.)
-  #
-  #   RubyGems generated Gzip Header: 10 bytes
-  #     magic(2) + method(1) + flag(1) + mtime(4) + exflag(1) + os(1) +
-  #     orig_name(0) + comment(0)
-  #
-  # Ideally, it must return a GZipReader without meaningless buffering.  We
-  # have lots of CRuby committers around so let's fix windows build when we
-  # received an error.
+
   def zipped_stream(entry)
-    Zlib::GzipReader.new entry
+    if defined? Rubinius or defined? Maglev then
+      # these implementations have working Zlib
+      zis = Zlib::GzipReader.new entry
+      dis = zis.read
+      is = StringIO.new(dis)
+    else
+      # This is Jamis Buck's Zlib workaround for some unknown issue
+      entry.read(10) # skip the gzip header
+      zis = Zlib::Inflate.new(-Zlib::MAX_WBITS)
+      is = StringIO.new(zis.inflate(entry.read))
+    end
+  ensure
+    zis.finish if zis
   end
 
 end