class Gem::Resolv::DNS::Message::MessageDecoder

def get_labels
  prev_index = @index
  save_index = nil
  d = []
  while true
    raise DecodeError.new("limit exceeded") if @limit <= @index
    case @data.getbyte(@index)
    when 0
      @index += 1
      if save_index
        @index = save_index
      end
      return d
    when 192..255
      idx = self.get_unpack('n')[0] & 0x3fff
      if prev_index <= idx
        raise DecodeError.new("non-backward name pointer")
      end
      prev_index = idx
      if !save_index
        save_index = @index
      end
      @index = idx
    else
      d << self.get_label
    end
  end
end