from

# File lib/rubygems/package/tar_header.rb, line 98
  def self.from(stream)
    header = stream.read 512
    empty = (header == "\00"" * 512)

    fields = header.unpack UNPACK_FORMAT

    name     = fields.shift
    mode     = fields.shift.oct
    uid      = fields.shift.oct
    gid      = fields.shift.oct
    size     = fields.shift.oct
    mtime    = fields.shift.oct
    checksum = fields.shift.oct
    typeflag = fields.shift
    linkname = fields.shift
    magic    = fields.shift
    version  = fields.shift.oct
    uname    = fields.shift
    gname    = fields.shift
    devmajor = fields.shift.oct
    devminor = fields.shift.oct
    prefix   = fields.shift

    new :name     => name,
        :mode     => mode,
        :uid      => uid,
        :gid      => gid,
        :size     => size,
        :mtime    => mtime,
        :checksum => checksum,
        :typeflag => typeflag,
        :linkname => linkname,
        :magic    => magic,
        :version  => version,
        :uname    => uname,
        :gname    => gname,
        :devmajor => devmajor,
        :devminor => devminor,
        :prefix   => prefix,

        :empty    => empty

    # HACK unfactor for Rubinius
    #new :name     => fields.shift,
    #    :mode     => fields.shift.oct,
    #    :uid      => fields.shift.oct,
    #    :gid      => fields.shift.oct,
    #    :size     => fields.shift.oct,
    #    :mtime    => fields.shift.oct,
    #    :checksum => fields.shift.oct,
    #    :typeflag => fields.shift,
    #    :linkname => fields.shift,
    #    :magic    => fields.shift,
    #    :version  => fields.shift.oct,
    #    :uname    => fields.shift,
    #    :gname    => fields.shift,
    #    :devmajor => fields.shift.oct,
    #    :devminor => fields.shift.oct,
    #    :prefix   => fields.shift,

    #    :empty => empty
  end