package lnwire import ( "io" "math" "github.com/btcsuite/btcd/chaincfg/chainhash" ) // QueryChannelRange is a message sent by a node in order to query the // receiving node of the set of open channel they know of with short channel // ID's after the specified block height, capped at the number of blocks beyond // that block height. This will be used by nodes upon initial connect to // synchronize their views of the network. type QueryChannelRange struct { // ChainHash denotes the target chain that we're trying to synchronize // channel graph state for. ChainHash chainhash.Hash // FirstBlockHeight is the first block in the query range. The // responder should send all new short channel IDs from this block // until this block plus the specified number of blocks. FirstBlockHeight uint32 // NumBlocks is the number of blocks beyond the first block that short // channel ID's should be sent for. NumBlocks uint32 // ExtraData is the set of data that was appended to this message to // fill out the full maximum transport message size. These fields can // be used to specify optional data such as custom TLV fields. ExtraData ExtraOpaqueData } // NewQueryChannelRange creates a new empty QueryChannelRange message. func NewQueryChannelRange() *QueryChannelRange { return &QueryChannelRange{} } // A compile time check to ensure QueryChannelRange implements the // lnwire.Message interface. var _ Message = (*QueryChannelRange)(nil) // Decode deserializes a serialized QueryChannelRange message stored in the // passed io.Reader observing the specified protocol version. // // This is part of the lnwire.Message interface. func (q *QueryChannelRange) Decode(r io.Reader, pver uint32) error { return ReadElements(r, q.ChainHash[:], &q.FirstBlockHeight, &q.NumBlocks, &q.ExtraData, ) } // Encode serializes the target QueryChannelRange into the passed io.Writer // observing the protocol version specified. // // This is part of the lnwire.Message interface. func (q *QueryChannelRange) Encode(w io.Writer, pver uint32) error { return WriteElements(w, q.ChainHash[:], q.FirstBlockHeight, q.NumBlocks, q.ExtraData, ) } // MsgType returns the integer uniquely identifying this message type on the // wire. // // This is part of the lnwire.Message interface. func (q *QueryChannelRange) MsgType() MessageType { return MsgQueryChannelRange } // MaxPayloadLength returns the maximum allowed payload size for a // QueryChannelRange complete message observing the specified protocol version. // // This is part of the lnwire.Message interface. func (q *QueryChannelRange) MaxPayloadLength(uint32) uint32 { return MaxMsgBody } // LastBlockHeight returns the last block height covered by the range of a // QueryChannelRange message. func (q *QueryChannelRange) LastBlockHeight() uint32 { // Handle overflows by casting to uint64. lastBlockHeight := uint64(q.FirstBlockHeight) + uint64(q.NumBlocks) - 1 if lastBlockHeight > math.MaxUint32 { return math.MaxUint32 } return uint32(lastBlockHeight) }