btcd/wire/msgfilteradd.go
Olaoluwa Osuntokun 48abfdf87c BIP0144+wire: add a MessageEncoding variant for serialization/deserialization
This commit modifies the existing wire.Message interface to introduce a
new MessageEncoding variant which dictates the exact encoding to be
used when serializing and deserializing messages. Such an option is now
necessary due to the segwit soft-fork package, as btcd will need to be
able to optionally encode transactions/blocks without witness data to
un-upgraded peers.

Two new functions have been introduced: ReadMessageWithEncodingN and
WriteMessageWithEncodingN which wrap BtcDecode/BtcEncode with the
desired encoding format.
2017-08-13 23:17:40 -05:00

82 lines
2.5 KiB
Go

// Copyright (c) 2014-2015 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"
)
const (
// MaxFilterAddDataSize is the maximum byte size of a data
// element to add to the Bloom filter. It is equal to the
// maximum element size of a script.
MaxFilterAddDataSize = 520
)
// MsgFilterAdd implements the Message interface and represents a bitcoin
// filteradd message. It is used to add a data element to an existing Bloom
// filter.
//
// This message was not added until protocol version BIP0037Version.
type MsgFilterAdd struct {
Data []byte
}
// BtcDecode decodes r using the bitcoin protocol encoding into the receiver.
// This is part of the Message interface implementation.
func (msg *MsgFilterAdd) BtcDecode(r io.Reader, pver uint32, enc MessageEncoding) error {
if pver < BIP0037Version {
str := fmt.Sprintf("filteradd message invalid for protocol "+
"version %d", pver)
return messageError("MsgFilterAdd.BtcDecode", str)
}
var err error
msg.Data, err = ReadVarBytes(r, pver, MaxFilterAddDataSize,
"filteradd data")
return err
}
// BtcEncode encodes the receiver to w using the bitcoin protocol encoding.
// This is part of the Message interface implementation.
func (msg *MsgFilterAdd) BtcEncode(w io.Writer, pver uint32, enc MessageEncoding) error {
if pver < BIP0037Version {
str := fmt.Sprintf("filteradd message invalid for protocol "+
"version %d", pver)
return messageError("MsgFilterAdd.BtcEncode", str)
}
size := len(msg.Data)
if size > MaxFilterAddDataSize {
str := fmt.Sprintf("filteradd size too large for message "+
"[size %v, max %v]", size, MaxFilterAddDataSize)
return messageError("MsgFilterAdd.BtcEncode", str)
}
return WriteVarBytes(w, pver, msg.Data)
}
// Command returns the protocol command string for the message. This is part
// of the Message interface implementation.
func (msg *MsgFilterAdd) Command() string {
return CmdFilterAdd
}
// MaxPayloadLength returns the maximum length the payload can be for the
// receiver. This is part of the Message interface implementation.
func (msg *MsgFilterAdd) MaxPayloadLength(pver uint32) uint32 {
return uint32(VarIntSerializeSize(MaxFilterAddDataSize)) +
MaxFilterAddDataSize
}
// NewMsgFilterAdd returns a new bitcoin filteradd message that conforms to the
// Message interface. See MsgFilterAdd for details.
func NewMsgFilterAdd(data []byte) *MsgFilterAdd {
return &MsgFilterAdd{
Data: data,
}
}