github.com/lbryio/lbcd@v0.22.119/wire/msggetcfheaders.go (about)

     1  // Copyright (c) 2017 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  // MsgGetCFHeaders is a message similar to MsgGetHeaders, but for committed
    14  // filter headers. It allows to set the FilterType field to get headers in the
    15  // chain of basic (0x00) or extended (0x01) headers.
    16  type MsgGetCFHeaders struct {
    17  	FilterType  FilterType
    18  	StartHeight uint32
    19  	StopHash    chainhash.Hash
    20  }
    21  
    22  // BtcDecode decodes r using the bitcoin protocol encoding into the receiver.
    23  // This is part of the Message interface implementation.
    24  func (msg *MsgGetCFHeaders) BtcDecode(r io.Reader, pver uint32, _ MessageEncoding) error {
    25  	err := readElement(r, &msg.FilterType)
    26  	if err != nil {
    27  		return err
    28  	}
    29  
    30  	err = readElement(r, &msg.StartHeight)
    31  	if err != nil {
    32  		return err
    33  	}
    34  
    35  	return readElement(r, &msg.StopHash)
    36  }
    37  
    38  // BtcEncode encodes the receiver to w using the bitcoin protocol encoding.
    39  // This is part of the Message interface implementation.
    40  func (msg *MsgGetCFHeaders) BtcEncode(w io.Writer, pver uint32, _ MessageEncoding) error {
    41  	err := writeElement(w, msg.FilterType)
    42  	if err != nil {
    43  		return err
    44  	}
    45  
    46  	err = writeElement(w, &msg.StartHeight)
    47  	if err != nil {
    48  		return err
    49  	}
    50  
    51  	return writeElement(w, &msg.StopHash)
    52  }
    53  
    54  // Command returns the protocol command string for the message.  This is part
    55  // of the Message interface implementation.
    56  func (msg *MsgGetCFHeaders) Command() string {
    57  	return CmdGetCFHeaders
    58  }
    59  
    60  // MaxPayloadLength returns the maximum length the payload can be for the
    61  // receiver.  This is part of the Message interface implementation.
    62  func (msg *MsgGetCFHeaders) MaxPayloadLength(pver uint32) uint32 {
    63  	// Filter type + uint32 + block hash
    64  	return 1 + 4 + chainhash.HashSize
    65  }
    66  
    67  // NewMsgGetCFHeaders returns a new bitcoin getcfheader message that conforms to
    68  // the Message interface using the passed parameters and defaults for the
    69  // remaining fields.
    70  func NewMsgGetCFHeaders(filterType FilterType, startHeight uint32,
    71  	stopHash *chainhash.Hash) *MsgGetCFHeaders {
    72  	return &MsgGetCFHeaders{
    73  		FilterType:  filterType,
    74  		StartHeight: startHeight,
    75  		StopHash:    *stopHash,
    76  	}
    77  }