btcd/wire/msggetcfilters.go

92 lines
2.7 KiB
Go

// Copyright (c) 2017 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 (
"io"
"github.com/btcsuite/btcd/chaincfg/chainhash"
)
// MaxGetCFiltersReqRange the maximum number of filters that may be requested in
// a getcfheaders message.
const MaxGetCFiltersReqRange = 1000
// MsgGetCFilters implements the Message interface and represents a bitcoin
// getcfilters message. It is used to request committed filters for a range of
// blocks.
type MsgGetCFilters struct {
FilterType FilterType
StartHeight uint32
StopHash chainhash.Hash
}
// BtcDecode decodes r using the bitcoin protocol encoding into the receiver.
// This is part of the Message interface implementation.
func (msg *MsgGetCFilters) BtcDecode(r io.Reader, pver uint32, _ MessageEncoding) error {
buf := binarySerializer.Borrow()
if _, err := io.ReadFull(r, buf[:1]); err != nil {
binarySerializer.Return(buf)
return err
}
msg.FilterType = FilterType(buf[0])
if _, err := io.ReadFull(r, buf[:4]); err != nil {
binarySerializer.Return(buf)
return err
}
msg.StartHeight = littleEndian.Uint32(buf[:4])
binarySerializer.Return(buf)
_, err := io.ReadFull(r, msg.StopHash[:])
return err
}
// BtcEncode encodes the receiver to w using the bitcoin protocol encoding.
// This is part of the Message interface implementation.
func (msg *MsgGetCFilters) BtcEncode(w io.Writer, pver uint32, _ MessageEncoding) error {
buf := binarySerializer.Borrow()
buf[0] = byte(msg.FilterType)
if _, err := w.Write(buf[:1]); err != nil {
binarySerializer.Return(buf)
return err
}
littleEndian.PutUint32(buf[:4], msg.StartHeight)
if _, err := w.Write(buf[:4]); err != nil {
binarySerializer.Return(buf)
return err
}
binarySerializer.Return(buf)
_, err := w.Write(msg.StopHash[:])
return err
}
// Command returns the protocol command string for the message. This is part
// of the Message interface implementation.
func (msg *MsgGetCFilters) Command() string {
return CmdGetCFilters
}
// MaxPayloadLength returns the maximum length the payload can be for the
// receiver. This is part of the Message interface implementation.
func (msg *MsgGetCFilters) MaxPayloadLength(pver uint32) uint32 {
// Filter type + uint32 + block hash
return 1 + 4 + chainhash.HashSize
}
// NewMsgGetCFilters returns a new bitcoin getcfilters message that conforms to
// the Message interface using the passed parameters and defaults for the
// remaining fields.
func NewMsgGetCFilters(filterType FilterType, startHeight uint32,
stopHash *chainhash.Hash) *MsgGetCFilters {
return &MsgGetCFilters{
FilterType: filterType,
StartHeight: startHeight,
StopHash: *stopHash,
}
}