class Gem::Resolv::DNS::Message

def encode
  return MessageEncoder.new {|msg|
    msg.put_pack('nnnnnn',
      @id,
      (@qr & 1) << 15 |
      (@opcode & 15) << 11 |
      (@aa & 1) << 10 |
      (@tc & 1) << 9 |
      (@rd & 1) << 8 |
      (@ra & 1) << 7 |
      (@rcode & 15),
      @question.length,
      @answer.length,
      @authority.length,
      @additional.length)
    @question.each {|q|
      name, typeclass = q
      msg.put_name(name)
      msg.put_pack('nn', typeclass::TypeValue, typeclass::ClassValue)
    }
    [@answer, @authority, @additional].each {|rr|
      rr.each {|r|
        name, ttl, data = r
        msg.put_name(name)
        msg.put_pack('nnN', data.class::TypeValue, data.class::ClassValue, ttl)
        msg.put_length16 {data.encode_rdata(msg)}
      }
    }
  }.to_s
end