Don't dial dupes

common/cmap.go

@@ -52,3 +52,13 @@ func (cm *CMap) Clear() {
 	defer cm.l.Unlock()
 	cm.m = make(map[string]interface{}, 0)
 }
+
+func (cm *CMap) Values() []interface{} {
+	cm.l.Lock()
+	defer cm.l.Unlock()
+	items := []interface{}{}
+	for _, v := range cm.m {
+		items = append(items, v)
+	}
+	return items
+}

p2p/connection.go

@@ -191,16 +191,18 @@ func (c *Connection) recvHandler() {
 
 FOR_LOOP:
 	for {
+		pktType, err := ReadUInt8Safe(c.bufReader)
 		if log.IsEnabledFor(logging.DEBUG) {
 			// peeking into bufReader
 			numBytes := c.bufReader.Buffered()
 			bytes, err := c.bufReader.Peek(MinInt(numBytes, 100))
-			log.Debug("recvHandler peeked: %X\nerr:%v", bytes, err)
+			if err != nil {
+				log.Debug("recvHandler packet type %X, peeked: %X", pktType, bytes)
+			}
 		}
-		pktType, err := ReadUInt8Safe(c.bufReader)
 		if err != nil {
 			if atomic.LoadUint32(&c.stopped) != 1 {
-				log.Info("%v failed @ recvHandler", c)
+				log.Info("%v failed @ recvHandler with err: %v", c, err)
 				c.Stop()
 			}
 			break FOR_LOOP

p2p/listener.go

@@ -85,6 +85,7 @@ func NewDefaultListener(protocol string, lAddr string) Listener {
 	return dl
 }
 
+// TODO: prevent abuse, esp a bunch of connections coming from the same IP range.
 func (l *DefaultListener) listenHandler() {
 	for {
 		conn, err := l.listener.Accept()

p2p/peer_manager.go

@@ -86,14 +86,17 @@ FOR_LOOP:
 
 // Ensures that sufficient peers are connected.
 func (pm *PeerManager) ensurePeers() {
-	numPeers := pm.sw.NumOutboundPeers()
-	numDialing := pm.sw.dialing.Size()
-	numToDial := minNumPeers - (numPeers + numDialing)
+	numOutPeers, _, numDialing := pm.sw.NumPeers()
+	numToDial := minNumPeers - (numOutPeers + numDialing)
 	if numToDial <= 0 {
 		return
 	}
+	toDial := NewCMap()
+
+	// Try to pick numToDial addresses to dial.
+	// TODO: improve logic.
 	for i := 0; i < numToDial; i++ {
-		newBias := MinInt(numPeers, 8)*10 + 10
+		newBias := MinInt(numOutPeers, 8)*10 + 10
 		var picked *NetAddress
 		// Try to fetch a new peer 3 times.
 		// This caps the maximum number of tries to 3 * numToDial.
@@ -103,7 +106,9 @@ func (pm *PeerManager) ensurePeers() {
 				log.Debug("Empty addrbook.")
 				return
 			}
-			if pm.sw.Peers().Has(picked) {
+			if toDial.Has(picked.String()) ||
+				pm.sw.IsDialing(picked) ||
+				pm.sw.Peers().Has(picked) {
 				continue
 			} else {
 				break
@@ -112,7 +117,12 @@ func (pm *PeerManager) ensurePeers() {
 		if picked == nil {
 			continue
 		}
-		// Dial picked address
+		toDial.Set(picked.String(), picked)
+	}
+
+	// Dial picked addresses
+	for _, item := range toDial.Values() {
+		picked := item.(*NetAddress)
 		go func() {
 			peer, err := pm.sw.DialPeerWithAddress(picked)
 			if err != nil {

p2p/peer_set.go

@@ -37,6 +37,7 @@ func NewPeerSet() *PeerSet {
 	}
 }
 
+// Returns false if peer with address is already in set.
 func (ps *PeerSet) Add(peer *Peer) bool {
 	ps.mtx.Lock()
 	defer ps.mtx.Unlock()

p2p/switch.go

@@ -118,6 +118,10 @@ func (s *Switch) DialPeerWithAddress(addr *NetAddress) (*Peer, error) {
 	return peer, nil
 }
 
+func (s *Switch) IsDialing(addr *NetAddress) bool {
+	return s.dialing.Has(addr.String())
+}
+
 func (s *Switch) Broadcast(pkt Packet) (numSuccess, numFailure int) {
 	if atomic.LoadUint32(&s.stopped) == 1 {
 		return
@@ -145,7 +149,7 @@ func (s *Switch) Receive(chName string) *InboundPacket {
 		return nil
 	}
 
-	log.Debug("Receive on [%v]", chName)
+	log.Debug("Waiting for [%v]", chName)
 	q := s.pktRecvQueues[chName]
 	if q == nil {
 		Panicf("Expected pktRecvQueues[%f], found none", chName)
@@ -155,17 +159,22 @@ func (s *Switch) Receive(chName string) *InboundPacket {
 	case <-s.quit:
 		return nil
 	case inPacket := <-q:
+		log.Debug("Received packet on [%v]", chName)
 		return inPacket
 	}
 }
 
-func (s *Switch) NumOutboundPeers() (count int) {
+// Returns the count of outbound/inbound and outbound-dialing peers.
+func (s *Switch) NumPeers() (outbound, inbound, dialing int) {
 	peers := s.peers.List()
 	for _, peer := range peers {
 		if peer.outbound {
-			count++
+			outbound++
+		} else {
+			inbound++
 		}
 	}
+	dialing = s.dialing.Size()
 	return
 }