github.com/lbryio/lbcd@v0.22.119/wire/msggetcfcheckpt.go (about) 1 // Copyright (c) 2018 The btcsuite developers 2 // Use of this source code is governed by an ISC 3 // license that can be found in the LICENSE file. 4 5 package wire 6 7 import ( 8 "io" 9 10 "github.com/lbryio/lbcd/chaincfg/chainhash" 11 ) 12 13 // MsgGetCFCheckpt is a request for filter headers at evenly spaced intervals 14 // throughout the blockchain history. It allows to set the FilterType field to 15 // get headers in the chain of basic (0x00) or extended (0x01) headers. 16 type MsgGetCFCheckpt struct { 17 FilterType FilterType 18 StopHash chainhash.Hash 19 } 20 21 // BtcDecode decodes r using the bitcoin protocol encoding into the receiver. 22 // This is part of the Message interface implementation. 23 func (msg *MsgGetCFCheckpt) BtcDecode(r io.Reader, pver uint32, _ MessageEncoding) error { 24 err := readElement(r, &msg.FilterType) 25 if err != nil { 26 return err 27 } 28 29 return readElement(r, &msg.StopHash) 30 } 31 32 // BtcEncode encodes the receiver to w using the bitcoin protocol encoding. 33 // This is part of the Message interface implementation. 34 func (msg *MsgGetCFCheckpt) BtcEncode(w io.Writer, pver uint32, _ MessageEncoding) error { 35 err := writeElement(w, msg.FilterType) 36 if err != nil { 37 return err 38 } 39 40 return writeElement(w, &msg.StopHash) 41 } 42 43 // Command returns the protocol command string for the message. This is part 44 // of the Message interface implementation. 45 func (msg *MsgGetCFCheckpt) Command() string { 46 return CmdGetCFCheckpt 47 } 48 49 // MaxPayloadLength returns the maximum length the payload can be for the 50 // receiver. This is part of the Message interface implementation. 51 func (msg *MsgGetCFCheckpt) MaxPayloadLength(pver uint32) uint32 { 52 // Filter type + uint32 + block hash 53 return 1 + chainhash.HashSize 54 } 55 56 // NewMsgGetCFCheckpt returns a new bitcoin getcfcheckpt message that conforms 57 // to the Message interface using the passed parameters and defaults for the 58 // remaining fields. 59 func NewMsgGetCFCheckpt(filterType FilterType, stopHash *chainhash.Hash) *MsgGetCFCheckpt { 60 return &MsgGetCFCheckpt{ 61 FilterType: filterType, 62 StopHash: *stopHash, 63 } 64 }