Get rid of Server's SendUDP goroutine.

client.go

@@ -298,37 +298,41 @@ func (client *Client) udpreceiver() {
 			outgoing.PutBytes(buf[1 : 1+(len(buf)-1)])
 			outbuf[0] = kind
 
-			// VoiceTarget
+			if target != 0x1f { // VoiceTarget
-			if target != 0x1f {
 				client.server.voicebroadcast <- &VoiceBroadcast{
 					client: client,
 					buf:    outbuf[0 : 1+outgoing.Size()],
 					target: target,
 				}
-				// Server loopback
+			} else { // Server loopback
-			} else {
+				buf := outbuf[0 : 1+outgoing.Size()]
-				client.sendUdp(&Message{
+				err := client.SendUDP(buf)
-					buf:    outbuf[0 : 1+outgoing.Size()],
+				if err != nil {
-					client: client,
+					client.Panicf("Unable to send UDP message: %v", err.Error())
-				})
+				}
 			}
 
 		case mumbleproto.UDPMessagePing:
-			client.server.udpsend <- &Message{
+			err := client.SendUDP(buf)
-				buf:    buf,
+			if err != nil {
-				client: client,
+				client.Panicf("Unable to send UDP message: %v", err.Error())
 			}
 		}
 	}
 }
 
-func (client *Client) sendUdp(msg *Message) {
+// Send buf as a UDP message. If the client does not have
+// an established UDP connection, the datagram will be tunelled
+// through the client's control channel (TCP).
+func (client *Client) SendUDP(buf []byte) error {
 	if client.udp {
-		client.Printf("Sent UDP!")
+		crypted := make([]byte, len(buf)+4)
-		client.server.udpsend <- msg
+		client.crypt.Encrypt(crypted, buf)
+		return client.server.SendUDP(crypted, client.udpaddr)
 	} else {
-		client.sendMessage(msg.buf)
+		return client.sendMessage(buf)
 	}
+	panic("unreachable")
 }
 
 // Send a Message to the client.  The Message in msg to the client's

server.go

@@ -64,7 +64,6 @@ type Server struct {
 	running  bool
 
 	incoming       chan *Message
-	udpsend        chan *Message
 	voicebroadcast chan *VoiceBroadcast
 	cfgUpdate      chan *KeyValuePair
 
@@ -150,7 +149,6 @@ func NewServer(id int64, addr string, port int) (s *Server, err error) {
 	s.hpclients = make(map[string]*Client)
 
 	s.incoming = make(chan *Message)
-	s.udpsend = make(chan *Message)
 	s.voicebroadcast = make(chan *VoiceBroadcast)
 	s.cfgUpdate = make(chan *KeyValuePair)
 	s.clientAuthenticated = make(chan *Client)
@@ -362,10 +360,10 @@ func (server *Server) handler() {
 				channel := vb.client.Channel
 				for _, client := range channel.clients {
 					if client != vb.client {
-						client.sendUdp(&Message{
+						err := client.SendUDP(vb.buf)
-							buf:    vb.buf,
+						if err != nil {
-							client: client,
+							client.Panic("Unable to send UDP: %v", err.Error())
-						})
+						}
 					}
 				}
 			}
@@ -878,21 +876,10 @@ func (s *Server) SetupUDP() (err error) {
 	return
 }
 
-func (s *Server) SendUDP() {
+// Send the content of buf as a UDP packet to addr.
-	for {
+func (s *Server) SendUDP(buf []byte, addr *net.UDPAddr) (err error) {
-		msg := <-s.udpsend
+	_, err = s.udpconn.WriteTo(buf, addr)
-		// Encrypted
+	return
-		if msg.client != nil {
-			crypted := make([]byte, len(msg.buf)+4)
-			msg.client.crypt.Encrypt(crypted, msg.buf)
-			s.udpconn.WriteTo(crypted, msg.client.udpaddr)
-			// Non-encrypted
-		} else if msg.address != nil {
-			s.udpconn.WriteTo(msg.buf, msg.address)
-		} else {
-			// Skipping
-		}
-	}
 }
 
 // Listen for and handle UDP packets.
@@ -928,10 +915,11 @@ func (server *Server) ListenUDP() {
 			_ = binary.Write(buffer, binary.BigEndian, server.cfg.Uint32Value("MaxUsers"))
 			_ = binary.Write(buffer, binary.BigEndian, server.cfg.Uint32Value("MaxBandwidth"))
 
-			server.udpsend <- &Message{
+			err = server.SendUDP(buffer.Bytes(), udpaddr)
-				buf:     buffer.Bytes(),
+			if err != nil {
-				address: udpaddr,
+				server.Print("Unable to write UDP packet: %v", err.Error())
 			}
+
 		} else {
 			server.handleUdpPacket(udpaddr, buf, nread)
 		}
@@ -1183,7 +1171,6 @@ func (s *Server) ListenAndMurmur() {
 	// Setup our UDP listener and spawn our reader and writer goroutines
 	s.SetupUDP()
 	go s.ListenUDP()
-	go s.SendUDP()
 
 	// Create a new listening TLS socket.
 	certFn := filepath.Join(Args.DataDir, "cert.pem")