multi: use hidden varint for cftypes count; make filter type enum, not uint8

blockchain/indexers/cfindex.go

@@ -15,6 +15,7 @@ import (
 	"github.com/btcsuite/btcutil/gcs"
 	"github.com/btcsuite/btcutil/gcs/builder"
 	"github.com/btcsuite/fastsha256"
+	"github.com/roasbeef/btcd/wire"
 )
 
 const (
@@ -149,7 +150,7 @@ func (idx *CfIndex) Create(dbTx database.Tx) error {
 	firstHeader := make([]byte, chainhash.HashSize)
 	err = dbStoreFilterHeader(
 		dbTx,
-		cfHeaderKeys[0],
+		cfHeaderKeys[wire.GCSFilterRegular],
 		&idx.chainParams.GenesisBlock.Header.PrevBlock,
 		firstHeader,
 	)
@@ -159,7 +160,7 @@ func (idx *CfIndex) Create(dbTx database.Tx) error {
 
 	return dbStoreFilterHeader(
 		dbTx,
-		cfHeaderKeys[1],
+		cfHeaderKeys[wire.GCSFilterExtended],
 		&idx.chainParams.GenesisBlock.Header.PrevBlock,
 		firstHeader,
 	)
@@ -168,8 +169,8 @@ func (idx *CfIndex) Create(dbTx database.Tx) error {
 // storeFilter stores a given filter, and performs the steps needed to
 // generate the filter's header.
 func storeFilter(dbTx database.Tx, block *btcutil.Block, f *gcs.Filter,
-	filterType uint8) error {
+	filterType wire.FilterType) error {
-	if filterType > maxFilterType {
+	if uint8(filterType) > maxFilterType {
 		return errors.New("unsupported filter type")
 	}
 
@@ -215,7 +216,8 @@ func (idx *CfIndex) ConnectBlock(dbTx database.Tx, block *btcutil.Block,
 		return err
 	}
 
-	if err := storeFilter(dbTx, block, f, 0); err != nil {
+	if err := storeFilter(dbTx, block, f,
+		wire.GCSFilterRegular); err != nil {
 		return err
 	}
 
@@ -224,7 +226,7 @@ func (idx *CfIndex) ConnectBlock(dbTx database.Tx, block *btcutil.Block,
 		return err
 	}
 
-	return storeFilter(dbTx, block, f, 1)
+	return storeFilter(dbTx, block, f, wire.GCSFilterExtended)
 }
 
 // DisconnectBlock is invoked by the index manager when a block has been
@@ -252,10 +254,11 @@ func (idx *CfIndex) DisconnectBlock(dbTx database.Tx, block *btcutil.Block,
 
 // FilterByBlockHash returns the serialized contents of a block's basic or
 // extended committed filter.
-func (idx *CfIndex) FilterByBlockHash(h *chainhash.Hash, filterType uint8) ([]byte, error) {
+func (idx *CfIndex) FilterByBlockHash(h *chainhash.Hash,
+	filterType wire.FilterType) ([]byte, error) {
 	var f []byte
 	err := idx.db.View(func(dbTx database.Tx) error {
-		if filterType > maxFilterType {
+		if uint8(filterType) > maxFilterType {
 			return errors.New("unsupported filter type")
 		}
 
@@ -268,15 +271,17 @@ func (idx *CfIndex) FilterByBlockHash(h *chainhash.Hash, filterType uint8) ([]by
 
 // FilterHeaderByBlockHash returns the serialized contents of a block's basic
 // or extended committed filter header.
-func (idx *CfIndex) FilterHeaderByBlockHash(h *chainhash.Hash, filterType uint8) ([]byte, error) {
+func (idx *CfIndex) FilterHeaderByBlockHash(h *chainhash.Hash,
+	filterType wire.FilterType) ([]byte, error) {
 	var fh []byte
 	err := idx.db.View(func(dbTx database.Tx) error {
-		if filterType > 1 {
+		if uint8(filterType) > maxFilterType {
 			return errors.New("unsupported filter type")
 		}
 
 		var err error
-		fh, err = dbFetchFilterHeader(dbTx, cfHeaderKeys[filterType], h)
+		fh, err = dbFetchFilterHeader(dbTx,
+			cfHeaderKeys[filterType], h)
 		return err
 	})
 	return fh, err

btcjson/chainsvrcmds.go

@@ -10,6 +10,8 @@ package btcjson
 import (
 	"encoding/json"
 	"fmt"
+
+	"github.com/roasbeef/btcd/wire"
 )
 
 // AddNodeSubCmd defines the type used in the addnode JSON-RPC command for the
@@ -282,12 +284,12 @@ func NewGetBlockTemplateCmd(request *TemplateRequest) *GetBlockTemplateCmd {
 // GetCFilterCmd defines the getcfilter JSON-RPC command.
 type GetCFilterCmd struct {
 	Hash       string
-	FilterType uint8
+	FilterType wire.FilterType
 }
 
 // NewGetCFilterCmd returns a new instance which can be used to issue a
 // getcfilter JSON-RPC command.
-func NewGetCFilterCmd(hash string, filterType uint8) *GetCFilterCmd {
+func NewGetCFilterCmd(hash string, filterType wire.FilterType) *GetCFilterCmd {
 	return &GetCFilterCmd{
 		Hash:       hash,
 		FilterType: filterType,
@@ -297,12 +299,13 @@ func NewGetCFilterCmd(hash string, filterType uint8) *GetCFilterCmd {
 // GetCFilterHeaderCmd defines the getcfilterheader JSON-RPC command.
 type GetCFilterHeaderCmd struct {
 	Hash       string
-	FilterType uint8
+	FilterType wire.FilterType
 }
 
 // NewGetCFilterHeaderCmd returns a new instance which can be used to issue a
 // getcfilterheader JSON-RPC command.
-func NewGetCFilterHeaderCmd(hash string, filterType uint8) *GetCFilterHeaderCmd {
+func NewGetCFilterHeaderCmd(hash string,
+	filterType wire.FilterType) *GetCFilterHeaderCmd {
 	return &GetCFilterHeaderCmd{
 		Hash:       hash,
 		FilterType: filterType,

btcjson/chainsvrcmds_test.go

@@ -12,6 +12,7 @@ import (
 	"testing"
 
 	"github.com/btcsuite/btcd/btcjson"
+	"github.com/btcsuite/btcd/wire"
 )
 
 // TestChainSvrCmds tests all of the chain server commands marshal and unmarshal
@@ -320,27 +321,33 @@ func TestChainSvrCmds(t *testing.T) {
 		{
 			name: "getcfilter",
 			newCmd: func() (interface{}, error) {
-				return btcjson.NewCmd("getcfilter", "123", 0)
+				return btcjson.NewCmd("getcfilter", "123",
+					wire.GCSFilterExtended)
 			},
 			staticCmd: func() interface{} {
-				return btcjson.NewGetCFilterCmd("123", 0)
+				return btcjson.NewGetCFilterCmd("123",
+					wire.GCSFilterExtended)
 			},
-			marshalled: `{"jsonrpc":"1.0","method":"getcfilter","params":["123",0],"id":1}`,
+			marshalled: `{"jsonrpc":"1.0","method":"getcfilter","params":["123",1],"id":1}`,
 			unmarshalled: &btcjson.GetCFilterCmd{
 				Hash:       "123",
+				FilterType: wire.GCSFilterExtended,
 			},
 		},
 		{
 			name: "getcfilterheader",
 			newCmd: func() (interface{}, error) {
-				return btcjson.NewCmd("getcfilterheader", "123", 0)
+				return btcjson.NewCmd("getcfilterheader", "123",
+					wire.GCSFilterExtended)
 			},
 			staticCmd: func() interface{} {
-				return btcjson.NewGetCFilterHeaderCmd("123", 0)
+				return btcjson.NewGetCFilterHeaderCmd("123",
+					wire.GCSFilterExtended)
 			},
-			marshalled: `{"jsonrpc":"1.0","method":"getcfilterheader","params":["123",0],"id":1}`,
+			marshalled: `{"jsonrpc":"1.0","method":"getcfilterheader","params":["123",1],"id":1}`,
 			unmarshalled: &btcjson.GetCFilterHeaderCmd{
 				Hash:       "123",
+				FilterType: wire.GCSFilterExtended,
 			},
 		},
 		{

peer/peer_test.go

@@ -542,7 +542,8 @@ func TestPeerListeners(t *testing.T) {
 		},
 		{
 			"OnGetCFilter",
-			wire.NewMsgGetCFilter(&chainhash.Hash{}, 0),
+			wire.NewMsgGetCFilter(&chainhash.Hash{},
+				wire.GCSFilterRegular),
 		},
 		{
 			"OnGetCFHeaders",
@@ -554,8 +555,8 @@ func TestPeerListeners(t *testing.T) {
 		},
 		{
 			"OnCFilter",
-			wire.NewMsgCFilter(&chainhash.Hash{}, 1,
+			wire.NewMsgCFilter(&chainhash.Hash{},
-				[]byte("payload")),
+				wire.GCSFilterRegular, []byte("payload")),
 		},
 		{
 			"OnCFHeaders",
@@ -563,7 +564,8 @@ func TestPeerListeners(t *testing.T) {
 		},
 		{
 			"OnCFTypes",
-			wire.NewMsgCFTypes([]uint8{0, 1}),
+			wire.NewMsgCFTypes([]wire.FilterType{
+				wire.GCSFilterRegular, wire.GCSFilterExtended}),
 		},
 		{
 			"OnFeeFilter",

rpcclient/chain.go

@@ -821,7 +821,7 @@ func (r FutureGetCFilterResult) Receive() (*wire.MsgCFilter, error) {
 //
 // See GetCFilter for the blocking version and more details.
 func (c *Client) GetCFilterAsync(blockHash *chainhash.Hash,
-	filterType uint8) FutureGetCFilterResult {
+	filterType wire.FilterType) FutureGetCFilterResult {
 	hash := ""
 	if blockHash != nil {
 		hash = blockHash.String()
@@ -833,7 +833,7 @@ func (c *Client) GetCFilterAsync(blockHash *chainhash.Hash,
 
 // GetCFilter returns a raw filter from the server given its block hash.
 func (c *Client) GetCFilter(blockHash *chainhash.Hash,
-	filterType uint8) (*wire.MsgCFilter, error) {
+	filterType wire.FilterType) (*wire.MsgCFilter, error) {
 	return c.GetCFilterAsync(blockHash, filterType).Receive()
 }
 
@@ -878,7 +878,7 @@ func (r FutureGetCFilterHeaderResult) Receive() (*wire.MsgCFHeaders, error) {
 //
 // See GetCFilterHeader for the blocking version and more details.
 func (c *Client) GetCFilterHeaderAsync(blockHash *chainhash.Hash,
-	filterType uint8) FutureGetCFilterHeaderResult {
+	filterType wire.FilterType) FutureGetCFilterHeaderResult {
 	hash := ""
 	if blockHash != nil {
 		hash = blockHash.String()
@@ -891,6 +891,6 @@ func (c *Client) GetCFilterHeaderAsync(blockHash *chainhash.Hash,
 // GetCFilterHeader returns a raw filter header from the server given its block
 // hash.
 func (c *Client) GetCFilterHeader(blockHash *chainhash.Hash,
-	filterType uint8) (*wire.MsgCFHeaders, error) {
+	filterType wire.FilterType) (*wire.MsgCFHeaders, error) {
 	return c.GetCFilterHeaderAsync(blockHash, filterType).Receive()
 }

server.go

@@ -881,7 +881,8 @@ func (sp *serverPeer) OnGetCFTypes(_ *peer.Peer, msg *wire.MsgGetCFTypes) {
 		return
 	}
 
-	cfTypesMsg := wire.NewMsgCFTypes([]uint8{0, 1})
+	cfTypesMsg := wire.NewMsgCFTypes([]wire.FilterType{
+		wire.GCSFilterRegular, wire.GCSFilterExtended})
 	sp.QueueMessage(cfTypesMsg, nil)
 }
 

wire/message_test.go

@@ -69,12 +69,13 @@ func TestMessage(t *testing.T) {
 	bh := NewBlockHeader(1, &chainhash.Hash{}, &chainhash.Hash{}, 0, 0)
 	msgMerkleBlock := NewMsgMerkleBlock(bh)
 	msgReject := NewMsgReject("block", RejectDuplicate, "duplicate block")
-	msgGetCFilter := NewMsgGetCFilter(&chainhash.Hash{}, 0)
+	msgGetCFilter := NewMsgGetCFilter(&chainhash.Hash{}, GCSFilterExtended)
 	msgGetCFHeaders := NewMsgGetCFHeaders()
 	msgGetCFTypes := NewMsgGetCFTypes()
-	msgCFilter := NewMsgCFilter(&chainhash.Hash{}, 1, []byte("payload"))
+	msgCFilter := NewMsgCFilter(&chainhash.Hash{}, GCSFilterExtended,
+		[]byte("payload"))
 	msgCFHeaders := NewMsgCFHeaders()
-	msgCFTypes := NewMsgCFTypes([]uint8{2})
+	msgCFTypes := NewMsgCFTypes([]FilterType{GCSFilterExtended})
 
 	tests := []struct {
 		in     Message    // Value to encode

wire/msgcfheaders.go

@@ -28,7 +28,7 @@ const (
 // MsgGetCFHeaders for details on requesting the headers.
 type MsgCFHeaders struct {
 	StopHash     chainhash.Hash
-	FilterType   uint8
+	FilterType   FilterType
 	HeaderHashes []*chainhash.Hash
 }
 

wire/msgcfilter.go

@@ -22,7 +22,7 @@ const (
 // getcfilter (MsgGetCFilter) message.
 type MsgCFilter struct {
 	BlockHash  chainhash.Hash
-	FilterType uint8
+	FilterType FilterType
 	Data       []byte
 }
 
@@ -99,7 +99,7 @@ func (msg *MsgCFilter) MaxPayloadLength(pver uint32) uint32 {
 
 // NewMsgCFilter returns a new bitcoin cfilter message that conforms to the
 // Message interface. See MsgCFilter for details.
-func NewMsgCFilter(blockHash *chainhash.Hash, filterType uint8,
+func NewMsgCFilter(blockHash *chainhash.Hash, filterType FilterType,
 	data []byte) *MsgCFilter {
 	return &MsgCFilter{
 		BlockHash:  *blockHash,

wire/msgcftypes.go

@@ -6,28 +6,40 @@ package wire
 
 import "io"
 
+// FilterType is used to represent a filter type.
+type FilterType uint8
+
+const (
+	// GCSFilterRegular is the regular filter type.
+	GCSFilterRegular FilterType = iota
+
+	// GCSFilterExtended is the extended filter type.
+	GCSFilterExtended
+)
+
 // MsgCFTypes is the cftypes message.
 type MsgCFTypes struct {
-	NumFilters       uint8
+	SupportedFilters []FilterType
-	SupportedFilters []uint8
 }
 
 // BtcDecode decodes r using the bitcoin protocol encoding into the receiver.
 // This is part of the Message interface implementation.
 func (msg *MsgCFTypes) BtcDecode(r io.Reader, pver uint32, _ MessageEncoding) error {
-	// Read the number of filter types supported
+	// Read the number of filter types supported.
-	err := readElement(r, &msg.NumFilters)
+	count, err := ReadVarInt(r, pver)
 	if err != nil {
 		return err
 	}
 
 	// Read each filter type.
-	msg.SupportedFilters = make([]uint8, msg.NumFilters)
+	msg.SupportedFilters = make([]FilterType, count)
-	for i := uint8(0); i < msg.NumFilters; i++ {
+	for i := uint64(0); i < count; i++ {
-		err = readElement(r, &msg.SupportedFilters[i])
+		var filterType uint8
+		err = readElement(r, &filterType)
 		if err != nil {
 			return err
 		}
+		msg.SupportedFilters[i] = FilterType(filterType)
 	}
 
 	return nil
@@ -36,9 +48,8 @@ func (msg *MsgCFTypes) BtcDecode(r io.Reader, pver uint32, _ MessageEncoding) er
 // BtcEncode encodes the receiver to w using the bitcoin protocol encoding.
 // This is part of the Message interface implementation.
 func (msg *MsgCFTypes) BtcEncode(w io.Writer, pver uint32, _ MessageEncoding) error {
-	// Write length of supported filters slice; don't trust that the caller
+	// Write length of supported filters slice. We assume it's deduplicated.
-	// has set it correctly.
+	err := WriteVarInt(w, pver, uint64(len(msg.SupportedFilters)))
-	err := writeElement(w, uint8(len(msg.SupportedFilters)))
 	if err != nil {
 		return err
 	}
@@ -78,15 +89,14 @@ func (msg *MsgCFTypes) Command() string {
 // MaxPayloadLength returns the maximum length the payload can be for the
 // receiver.  This is part of the Message interface implementation.
 func (msg *MsgCFTypes) MaxPayloadLength(pver uint32) uint32 {
-	// 1 byte for NumFilters, and 1 byte for up to 255 filter types.
+	// 2 bytes for filter count, and 1 byte for up to 256 filter types.
-	return 256
+	return 258
 }
 
 // NewMsgCFTypes returns a new bitcoin cftypes message that conforms to the
 // Message interface. See MsgCFTypes for details.
-func NewMsgCFTypes(filterTypes []uint8) *MsgCFTypes {
+func NewMsgCFTypes(filterTypes []FilterType) *MsgCFTypes {
 	return &MsgCFTypes{
-		NumFilters:       uint8(len(filterTypes)),
 		SupportedFilters: filterTypes,
 	}
 }

wire/msggetcfheaders.go

@@ -17,7 +17,7 @@ import (
 type MsgGetCFHeaders struct {
 	BlockLocatorHashes []*chainhash.Hash
 	HashStop           chainhash.Hash
-	FilterType         uint8
+	FilterType         FilterType
 }
 
 // AddBlockLocatorHash adds a new block locator hash to the message.

wire/msggetcfilter.go

@@ -14,7 +14,7 @@ import (
 // getcfilter message. It is used to request a committed filter for a block.
 type MsgGetCFilter struct {
 	BlockHash  chainhash.Hash
-	FilterType uint8
+	FilterType FilterType
 }
 
 // BtcDecode decodes r using the bitcoin protocol encoding into the receiver.
@@ -53,7 +53,8 @@ func (msg *MsgGetCFilter) MaxPayloadLength(pver uint32) uint32 {
 // NewMsgGetCFilter returns a new bitcoin getcfilter message that conforms to
 // the Message interface using the passed parameters and defaults for the
 // remaining fields.
-func NewMsgGetCFilter(blockHash *chainhash.Hash, filterType uint8) *MsgGetCFilter {
+func NewMsgGetCFilter(blockHash *chainhash.Hash,
+	filterType FilterType) *MsgGetCFilter {
 	return &MsgGetCFilter{
 		BlockHash:  *blockHash,
 		FilterType: filterType,