extract_tar_gz

# File lib/rubygems/package.rb, line 385
  def extract_tar_gz(io, destination_dir, pattern = "*") # :nodoc:
    directories = [] if dir_mode
    open_tar_gz io do |tar|
      tar.each do |entry|
        next unless File.fnmatch pattern, entry.full_name, File::FNM_DOTMATCH

        destination = install_location entry.full_name, destination_dir

        FileUtils.rm_rf destination

        mkdir_options = {}
        mkdir_options[:mode] = dir_mode ? 0755 : (entry.header.mode if entry.directory?)
        mkdir =
          if entry.directory?
            destination
          else
            File.dirname destination
          end
        directories << mkdir if directories

        mkdir_p_safe mkdir, mkdir_options, destination_dir, entry.full_name

        File.open destination, 'wb' do |out|
          out.write entry.read
          FileUtils.chmod file_mode(entry.header.mode), destination
        end if entry.file?

        File.symlink(entry.header.linkname, destination) if entry.symlink?

        verbose destination
      end
    end

    if directories
      directories.uniq!
      File.chmod(dir_mode, *directories)
    end
  end