79 lines
2.4 KiB
Go
79 lines
2.4 KiB
Go
|
// Copyright (c) 2013-2015 The btcsuite developers
|
||
|
|
// Use of this source code is governed by an ISC
|
||
|
|
// license that can be found in the LICENSE file.
|
||
|
|
|
||
|
|
package wire
|
||
|
|
|
||
|
|
import (
|
||
|
|
"fmt"
|
||
|
|
"io"
|
||
|
|
)
|
||
|
|
|
||
|
|
// MsgPong implements the Message interface and represents a bitcoin pong
|
||
|
|
// message which is used primarily to confirm that a connection is still valid
|
||
|
|
// in response to a bitcoin ping message (MsgPing).
|
||
|
|
//
|
||
|
|
// This message was not added until protocol versions AFTER BIP0031Version.
|
||
|
|
type MsgPong struct {
|
||
|
|
// Unique value associated with message that is used to identify
|
||
|
|
// specific ping message.
|
||
|
|
Nonce uint64
|
||
|
|
}
|
||
|
|
|
||
|
|
// BtcDecode decodes r using the bitcoin protocol encoding into the receiver.
|
||
|
|
// This is part of the Message interface implementation.
|
||
|
|
func (msg *MsgPong) BtcDecode(r io.Reader, pver uint32, enc MessageEncoding) error {
|
||
|
|
// NOTE: <= is not a mistake here. The BIP0031 was defined as AFTER
|
||
|
|
// the version unlike most others.
|
||
|
|
if pver <= BIP0031Version {
|
||
|
|
str := fmt.Sprintf("pong message invalid for protocol "+
|
||
|
|
"version %d", pver)
|
||
|
|
return messageError("MsgPong.BtcDecode", str)
|
||
|
|
}
|
||
|
|
|
||
|
|
return readElement(r, &msg.Nonce)
|
||
|
|
}
|
||
|
|
|
||
|
|
// BtcEncode encodes the receiver to w using the bitcoin protocol encoding.
|
||
|
|
// This is part of the Message interface implementation.
|
||
|
|
func (msg *MsgPong) BtcEncode(w io.Writer, pver uint32, enc MessageEncoding) error {
|
||
|
|
// NOTE: <= is not a mistake here. The BIP0031 was defined as AFTER
|
||
|
|
// the version unlike most others.
|
||
|
|
if pver <= BIP0031Version {
|
||
|
|
str := fmt.Sprintf("pong message invalid for protocol "+
|
||
|
|
"version %d", pver)
|
||
|
|
return messageError("MsgPong.BtcEncode", str)
|
||
|
|
}
|
||
|
|
|
||
|
|
return writeElement(w, msg.Nonce)
|
||
|
|
}
|
||
|
|
|
||
|
|
// Command returns the protocol command string for the message. This is part
|
||
|
|
// of the Message interface implementation.
|
||
|
|
func (msg *MsgPong) Command() string {
|
||
|
|
return CmdPong
|
||
|
|
}
|
||
|
|
|
||
|
|
// MaxPayloadLength returns the maximum length the payload can be for the
|
||
|
|
// receiver. This is part of the Message interface implementation.
|
||
|
|
func (msg *MsgPong) MaxPayloadLength(pver uint32) uint32 {
|
||
|
|
plen := uint32(0)
|
||
|
|
// The pong message did not exist for BIP0031Version and earlier.
|
||
|
|
// NOTE: > is not a mistake here. The BIP0031 was defined as AFTER
|
||
|
|
// the version unlike most others.
|
||
|
|
if pver > BIP0031Version {
|
||
|
|
// Nonce 8 bytes.
|
||
|
|
plen += 8
|
||
|
|
}
|
||
|
|
|
||
|
|
return plen
|
||
|
|
}
|
||
|
|
|
||
|
|
// NewMsgPong returns a new bitcoin pong message that conforms to the Message
|
||
|
|
// interface. See MsgPong for details.
|
||
|
|
func NewMsgPong(nonce uint64) *MsgPong {
|
||
|
|
return &MsgPong{
|
||
|
|
Nonce: nonce,
|
||
|
|
}
|
||
|
|
}
|