Example of rack #571

obscure-gz-writing.rb

require 'stringio'
require 'zlib'

GZ_FILE = "rack-issue-571.gz"

class VerboseStringIO < StringIO
  attr_accessor :log

  def initialize(*args)
    @log = []
    super
  end

  def write(input)
    STDOUT.puts "input:           #{input.inspect}"
    STDOUT.puts "@log before <<: #{@log.inspect}"
    @log << input
    super
    STDOUT.puts "@log after <<:  #{@log.inspect}\n\n"
  end
end

string_io = VerboseStringIO.new()
gzw       = Zlib::GzipWriter.new(string_io)
gzw.write("hello\n"); gzw.flush
gzw.write("there\n"); gzw.flush
gzw.close

# Write out our log of what was "written" to one IO-like thing,
# to another IO-like thing
File.open(GZ_FILE, "w") { |handle| handle.write string_io.log.join }

Zlib::GzipReader.open(GZ_FILE) { |gzr| print gzr.read }
File.unlink(GZ_FILE)

run.txt

s@sd ~/code$ ruby -v
jruby 1.7.4 (1.9.3p392) 2013-05-16 2390d3b on OpenJDK Server VM 1.7.0 [linux-i386]
s@sd ~/code$ ruby jruby-test.rb 
input:           "\x1F\x8B\b\x00\x00\x00\x00\x00\x00\xFF"
@log before <<: []
@log after <<:  ["\x1F\x8B\b\x00\x00\x00\x00\x00\x00\xFF"]

input:           "\xCAH\xCD\xC9\xC9\xE7\x02\x00\x00\x00\xFF\xFF"
@log before <<: ["\xCAH\xCD\xC9\xC9\xE7\x02\x00\x00\x00"]
@log after <<:  ["\xCAH\xCD\xC9\xC9\xE7\x02\x00\x00\x00", "\xCAH\xCD\xC9\xC9\xE7\x02\x00\x00\x00\xFF\xFF"]

input:           "*\xC9H-J\xE5\x02\x00\x00\x00\xFF\xFF"
@log before <<: ["*\xC9H-J\xE5\x02\x00\x00\x00", "*\xC9H-J\xE5\x02\x00\x00\x00\xFF\xFF"]
@log after <<:  ["*\xC9H-J\xE5\x02\x00\x00\x00", "*\xC9H-J\xE5\x02\x00\x00\x00\xFF\xFF", "*\xC9H-J\xE5\x02\x00\x00\x00\xFF\xFF"]

input:           "\x03\x00\\#\x1C2\f\x00\x00\x00"
@log before <<: ["\x03\x00\\#\x1C2\f\x00\x00\x00", "\x03\x00\\#\x1C2\f\x00\x00\x00\xFF\xFF", "\x03\x00\\#\x1C2\f\x00\x00\x00\xFF\xFF"]
@log after <<:  ["\x03\x00\\#\x1C2\f\x00\x00\x00", "\x03\x00\\#\x1C2\f\x00\x00\x00\xFF\xFF", "\x03\x00\\#\x1C2\f\x00\x00\x00\xFF\xFF", "\x03\x00\\#\x1C2\f\x00\x00\x00"]

Zlib::GzipFile::Error: not in gzip format
  initialize at org/jruby/ext/zlib/JZlibRubyGzipReader.java:110
         new at org/jruby/ext/zlib/JZlibRubyGzipReader.java:56
        open at org/jruby/ext/zlib/JZlibRubyGzipReader.java:72
      (root) at jruby-test.rb:33


s@sd ~/code$ ruby -v
ruby 2.0.0p247 (2013-06-27 revision 41674) [x86_64-linux]
s@sd ~/code$ ruby jruby-test.rb 
input:           "\x1F\x8B\b\x00>I\xDBQ\x00\x03"
@log before <<: []
@log after <<:  ["\x1F\x8B\b\x00>I\xDBQ\x00\x03"]

input:           "\xCAH\xCD\xC9\xC9\xE7\x02\x00\x00\x00\xFF\xFF"
@log before <<: ["\x1F\x8B\b\x00>I\xDBQ\x00\x03"]
@log after <<:  ["\x1F\x8B\b\x00>I\xDBQ\x00\x03", "\xCAH\xCD\xC9\xC9\xE7\x02\x00\x00\x00\xFF\xFF"]

input:           "*\xC9H-J\xE5\x02\x00\x00\x00\xFF\xFF"
@log before <<: ["\x1F\x8B\b\x00>I\xDBQ\x00\x03", "\xCAH\xCD\xC9\xC9\xE7\x02\x00\x00\x00\xFF\xFF"]
@log after <<:  ["\x1F\x8B\b\x00>I\xDBQ\x00\x03", "\xCAH\xCD\xC9\xC9\xE7\x02\x00\x00\x00\xFF\xFF", "*\xC9H-J\xE5\x02\x00\x00\x00\xFF\xFF"]

input:           "\x03\x00\\#\x1C2\f\x00\x00\x00"
@log before <<: ["\x1F\x8B\b\x00>I\xDBQ\x00\x03", "\xCAH\xCD\xC9\xC9\xE7\x02\x00\x00\x00\xFF\xFF", "*\xC9H-J\xE5\x02\x00\x00\x00\xFF\xFF"]
@log after <<:  ["\x1F\x8B\b\x00>I\xDBQ\x00\x03", "\xCAH\xCD\xC9\xC9\xE7\x02\x00\x00\x00\xFF\xFF", "*\xC9H-J\xE5\x02\x00\x00\x00\xFF\xFF", "\x03\x00\\#\x1C2\f\x00\x00\x00"]

hello
there