btcd/wire/msgsendheaders.go
David Hill ae00fff14a wire: Implement sendheaders command (BIP0130)
This implements the wire protocol encoding portion of a new
sendheaders message as described by BIP0130. It purpose is to request
that a peer sends header commands instead of inv commands when
announcing new blocks. This includes a protocol version bump to 70012
and a wire version bump to 0.4.0.

Note that this does not implement logic to handle the command in btcd,
rather it only makes the command available at the wire protocol level.
A future commit which honors the command and therefore provides full
BIP0130 support is still required.
2016-02-05 12:41:39 -05:00

61 lines
1.9 KiB
Go

// Copyright (c) 2016 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"
)
// MsgSendHeaders implements the Message interface and represents a bitcoin
// sendheaders message. It is used to request the peer send block headers
// rather than inventory vectors.
//
// This message has no payload and was not added until protocol versions
// starting with SendHeadersVersion.
type MsgSendHeaders struct{}
// BtcDecode decodes r using the bitcoin protocol encoding into the receiver.
// This is part of the Message interface implementation.
func (msg *MsgSendHeaders) BtcDecode(r io.Reader, pver uint32) error {
if pver < SendHeadersVersion {
str := fmt.Sprintf("sendheaders message invalid for protocol "+
"version %d", pver)
return messageError("MsgSendHeaders.BtcDecode", str)
}
return nil
}
// BtcEncode encodes the receiver to w using the bitcoin protocol encoding.
// This is part of the Message interface implementation.
func (msg *MsgSendHeaders) BtcEncode(w io.Writer, pver uint32) error {
if pver < SendHeadersVersion {
str := fmt.Sprintf("sendheaders message invalid for protocol "+
"version %d", pver)
return messageError("MsgSendHeaders.BtcEncode", str)
}
return nil
}
// Command returns the protocol command string for the message. This is part
// of the Message interface implementation.
func (msg *MsgSendHeaders) Command() string {
return CmdSendHeaders
}
// MaxPayloadLength returns the maximum length the payload can be for the
// receiver. This is part of the Message interface implementation.
func (msg *MsgSendHeaders) MaxPayloadLength(pver uint32) uint32 {
return 0
}
// NewMsgSendHeaders returns a new bitcoin sendheaders message that conforms to
// the Message interface. See MsgSendHeaders for details.
func NewMsgSendHeaders() *MsgSendHeaders {
return &MsgSendHeaders{}
}