fix panic when a client disconnects

main.go

@@ -55,18 +55,12 @@ func newProgram(rtspPort int, rtpPort int, rtcpPort int) (*program, error) {
 }
 
 func (p *program) run() {
-	var wg sync.WaitGroup
+	go p.rtpl.run()
+	go p.rtcpl.run()
+	go p.rtspl.run()
 
-	wg.Add(1)
-	go p.rtpl.run(wg)
-
-	wg.Add(1)
-	go p.rtcpl.run(wg)
-
-	wg.Add(1)
-	go p.rtspl.run(wg)
-
-	wg.Wait()
+	infty := make(chan struct{})
+	<-infty
 }
 
 func (p *program) handleRtp(buf []byte) {

rtsp_client.go

@@ -10,7 +10,6 @@ import (
 	"net/url"
 	"strconv"
 	"strings"
-	"sync"
 
 	"rtsp-server/rtsp"
 )
@@ -40,20 +39,26 @@ func newRtspClient(p *program, nconn net.Conn) *rtspClient {
 }
 
 func (c *rtspClient) close() error {
+	// already deleted
+	if _, ok := c.p.clients[c]; !ok {
+		return nil
+	}
+
 	delete(c.p.clients, c)
+	c.nconn.Close()
 
 	if c.p.streamAuthor == c {
 		c.p.streamAuthor = nil
 		c.p.streamSdp = nil
 
-		// if the streamer has disconnected
+		// if the publisher has disconnected
 		// close all other connections
 		for oc := range c.p.clients {
 			oc.close()
 		}
 	}
 
-	return c.nconn.Close()
+	return nil
 }
 
 func (c *rtspClient) log(format string, args ...interface{}) {
@@ -61,8 +66,7 @@ func (c *rtspClient) log(format string, args ...interface{}) {
 	log.Printf(format, args...)
 }
 
-func (c *rtspClient) run(wg sync.WaitGroup) {
-	defer wg.Done()
+func (c *rtspClient) run() {
 	defer c.log("disconnected")
 	defer func() {
 		c.p.mutex.Lock()
@@ -278,7 +282,7 @@ func (c *rtspClient) run(wg sync.WaitGroup) {
 								fmt.Sprintf("client_port=%d-%d", clientPort1, clientPort2),
 								// use two fake server ports, since we do not want to receive feedback
 								// from the client
-								fmt.Sprintf("server_port=%d-%d", c.p.rtpPort + 2, c.p.rtcpPort + 2),
+								fmt.Sprintf("server_port=%d-%d", c.p.rtpPort+2, c.p.rtcpPort+2),
 								"ssrc=1234ABCD",
 							}, ";"),
 							"Session": "12345678",

rtsp_listener.go

@@ -3,7 +3,6 @@ package main
 import (
 	"log"
 	"net"
-	"sync"
 )
 
 type rtspListener struct {
@@ -32,9 +31,7 @@ func (l *rtspListener) log(format string, args ...interface{}) {
 	log.Printf("[RTSP listener] "+format, args...)
 }
 
-func (l *rtspListener) run(wg sync.WaitGroup) {
-	defer wg.Done()
-
+func (l *rtspListener) run() {
 	for {
 		nconn, err := l.netl.AcceptTCP()
 		if err != nil {
@@ -42,7 +39,6 @@ func (l *rtspListener) run(wg sync.WaitGroup) {
 		}
 
 		rsc := newRtspClient(l.p, nconn)
-		wg.Add(1)
-		go rsc.run(wg)
+		go rsc.run()
 	}
 }

udp_listener.go

@@ -3,7 +3,6 @@ package main
 import (
 	"log"
 	"net"
-	"sync"
 )
 
 type udpListener struct {
@@ -34,9 +33,7 @@ func (l *udpListener) log(format string, args ...interface{}) {
 	log.Printf("["+l.logPrefix+" listener] "+format, args...)
 }
 
-func (l *udpListener) run(wg sync.WaitGroup) {
-	defer wg.Done()
-
+func (l *udpListener) run() {
 	buf := make([]byte, 2048) // UDP MTU is 1400
 
 	for {