add support for the ping rpc command.

And the pingtime and pingwait fields of getpeerinfo.

peer.go

@@ -162,6 +162,10 @@ type peer struct {
 	blockProcessed     chan bool
 	quit               chan bool
 	userAgent          string
+	pingStatsMtx       sync.Mutex // protects lastPing*
+	lastPingNonce      uint64     // Set to nonce if we have a pending ping.
+	lastPingTime       time.Time  // Time we sent last ping.
+	lastPingMicros     int64      // Time for last ping to return.
 }
 
 // String returns the peer's address and directionality as a human-readable
@@ -921,6 +925,30 @@ func (p *peer) handlePingMsg(msg *btcwire.MsgPing) {
 	}
 }
 
+// handlePongMsg is invoked when a peer recieved a pong bitcoin message.
+// recent clients (protocol version > BIP0031Version), and if we had send a ping
+// previosuly we update our ping time statistics. If the client is too old or
+// we had not send a ping we ignore it.
+func (p *peer) handlePongMsg(msg *btcwire.MsgPong) {
+	p.pingStatsMtx.Lock()
+	defer p.pingStatsMtx.Unlock()
+
+	// Arguably we could use a buffered channel here sending data
+	// in a fifo manner whenever we send a ping, or a list keeping track of
+	// the times of each ping. For now we just make a best effort and
+	// only record stats if it was for the last ping sent. Any preceding
+	// and overlapping pings will be ignored. It is unlikely to occur
+	// without large usage of the ping rpc call since we ping
+	// infrequently enough that if they overlap we would have timed out
+	// the peer.
+	if p.protocolVersion > btcwire.BIP0031Version &&
+		p.lastPingNonce != 0 && msg.Nonce == p.lastPingNonce {
+		p.lastPingMicros = time.Now().Sub(p.lastPingTime).Nanoseconds()
+		p.lastPingMicros /= 1000 // convert to usec.
+		p.lastPingNonce = 0
+	}
+}
+
 // readMessage reads the next bitcoin message from the peer with logging.
 func (p *peer) readMessage() (msg btcwire.Message, buf []byte, err error) {
 	msg, buf, err = btcwire.ReadMessage(p.conn, p.protocolVersion, p.btcnet)
@@ -1092,8 +1120,7 @@ out:
 			markConnected = true
 
 		case *btcwire.MsgPong:
-			// Don't do anything, but could try to work out network
-			// timing or similar.
+			p.handlePongMsg(msg)
 
 		case *btcwire.MsgAlert:
 			p.server.BroadcastMessage(msg, p)
@@ -1324,13 +1351,20 @@ out:
 			// specially.
 			peerLog.Tracef("%s: recieved from queuehandler", p)
 			reset := true
-			switch msg.msg.(type) {
+			switch m := msg.msg.(type) {
 			case *btcwire.MsgVersion:
 				// should get an ack
 			case *btcwire.MsgGetAddr:
 				// should get addresses
 			case *btcwire.MsgPing:
 				// expects pong
+				// Also set up statistics.
+				p.pingStatsMtx.Lock()
+				if p.protocolVersion > btcwire.BIP0031Version {
+					p.lastPingNonce = m.Nonce
+					p.lastPingTime = time.Now()
+				}
+				p.pingStatsMtx.Unlock()
 			case *btcwire.MsgMemPool:
 				// Should return an inv.
 			case *btcwire.MsgGetData:

rpcserver.go

@@ -66,6 +66,7 @@ var rpcHandlersBeforeInit = map[string]commandHandler{
 	"getrawmempool":        handleGetRawMempool,
 	"getrawtransaction":    handleGetRawTransaction,
 	"help":                 handleHelp,
+	"ping":                 handlePing,
 	"sendrawtransaction":   handleSendRawTransaction,
 	"setgenerate":          handleSetGenerate,
 	"stop":                 handleStop,
@@ -134,7 +135,6 @@ var rpcUnimplemented = map[string]bool{
 	"getnetworkhashps": true,
 	"getnewaddress":    true,
 	"getwork":          true,
-	"ping":                   true,
 }
 
 // rpcServer holds the items the rpc server may need to access (config,
@@ -1037,7 +1037,7 @@ NOTE: btcd does not mine so this will always return false. The call is provided
 for compatibility only.`,
 	"getpeerinfo": `
 NOTE: btcd does not currently implement all fields. the "bytessent",
-"bytesrecv", "pingtime", "pingwait" and "syncnode" fields are not yet
+"bytesrecv" and "syncnode" fields are not yet
 implemented.`,
 	"sendrawtransaction": `
 NOTE: btcd does not currently support the "allowhighfees" parameter.`,
@@ -1092,6 +1092,19 @@ func handleHelp(s *rpcServer, cmd btcjson.Cmd) (interface{}, error) {
 	return getHelpText(help.Command)
 }
 
+// handlePing implements the ping command.
+func handlePing(s *rpcServer, cmd btcjson.Cmd) (interface{}, error) {
+	// Ask server to ping \o_
+	nonce, err := btcwire.RandomUint64()
+	if err != nil {
+		return nil, fmt.Errorf("Not sending ping - can not generate "+
+			"nonce: %v", err)
+	}
+	s.server.BroadcastMessage(btcwire.NewMsgPing(nonce))
+
+	return nil, nil
+}
+
 // handleSendRawTransaction implements the sendrawtransaction command.
 func handleSendRawTransaction(s *rpcServer, cmd btcjson.Cmd) (interface{}, error) {
 	c := cmd.(*btcjson.SendRawTransactionCmd)

server.go

@@ -266,6 +266,8 @@ type PeerInfo struct {
 	LastRecv       int64  `json:"lastrecv"`
 	BytesSent      int    `json:"bytessent"`
 	BytesRecv      int    `json:"bytesrecv"`
+	PingTime       int64  `json:"pingtime"`
+	PingWait       int64  `json:"pingwait,omitempty"`
 	ConnTime       int64  `json:"conntime"`
 	Version        uint32 `json:"version"`
 	SubVer         string `json:"subver"`
@@ -333,6 +335,14 @@ func (s *server) handleQuery(querymsg interface{}, state *peerState) {
 				BanScore:       0,
 				SyncNode:       false, // TODO(oga) for now. bm knows this.
 			}
+			p.pingStatsMtx.Lock()
+			info.PingTime = p.lastPingMicros
+			if p.lastPingNonce != 0 {
+				wait := time.Now().Sub(p.lastPingTime).Nanoseconds()
+				// We actually want microseconds.
+				info.PingWait = wait / 1000
+			}
+			p.pingStatsMtx.Unlock()
 			infos = append(infos, info)
 		})
 		msg.reply <- infos

util/btcctl/btcctl.go

@@ -67,6 +67,7 @@ var commandHandlers = map[string]*handlerData{
 	"help":                 &handlerData{0, 1, displayGeneric, nil, makeHelp, "[commandName]"},
 	"importprivkey":        &handlerData{1, 2, displayGeneric, []conversionHandler{nil, nil, toBool}, makeImportPrivKey, "<wifprivkey> [label] [rescan=true]"},
 	"listtransactions":     &handlerData{0, 3, displayJSONDump, []conversionHandler{nil, toInt, toInt}, makeListTransactions, "[account] [count=10] [from=0]"},
+	"ping":                 &handlerData{0, 0, displayGeneric, nil, makePing, ""},
 	"verifychain":          &handlerData{0, 2, displayJSONDump, []conversionHandler{toInt, toInt}, makeVerifyChain, "[level] [numblocks]"},
 	"sendrawtransaction":   &handlerData{1, 0, displayGeneric, nil, makeSendRawTransaction, "<hextx>"},
 	"stop":                 &handlerData{0, 0, displayGeneric, nil, makeStop, ""},
@@ -353,6 +354,11 @@ func makeListTransactions(args []interface{}) (btcjson.Cmd, error) {
 	return btcjson.NewListTransactionsCmd("btcctl", optargs...)
 }
 
+// makePing generates the cmd structure for ping commands.
+func makePing(args []interface{}) (btcjson.Cmd, error) {
+	return btcjson.NewPingCmd("btcctl")
+}
+
 // makeSendRawTransaction generates the cmd structure for sendrawtransaction
 // commands.
 func makeSendRawTransaction(args []interface{}) (btcjson.Cmd, error) {