Harden UDP audio transport and logging

fileplayback/player.go

@@ -1,6 +1,7 @@
 package fileplayback
 
 import (
+	"context"
 	"encoding/binary"
 	"errors"
 	"io"
@@ -18,6 +19,8 @@ type Player struct {
 	filename  string
 	audioChan chan gumble.AudioBuffer
 	stopChan  chan struct{}
+	ctx       context.Context
+	cancel    context.CancelFunc
 	mutex     sync.Mutex
 	playing   bool
 	errorFunc func(error)
@@ -73,6 +76,7 @@ func (p *Player) PlayFile(filename string) error {
 	// Start the file reading goroutine
 	p.playing = true
 	p.stopChan = make(chan struct{})
+	p.ctx, p.cancel = context.WithCancel(context.Background())
 	go p.readFileAudio()
 
 	return nil
@@ -88,17 +92,23 @@ func (p *Player) Stop() error {
 	}
 
 	close(p.stopChan)
+	if p.cancel != nil {
+		p.cancel()
+		p.cancel = nil
+	}
 	p.playing = false
+	localPlayback := p.localPlayback
+	p.mutex.Unlock()
 
-	if p.localPlayback != nil {
-		p.localPlayback(nil)
+	if localPlayback != nil {
+		localPlayback(nil)
 	}
 
-	// Drain the audio channel
+	// Drain the audio channel.
 	for len(p.audioChan) > 0 {
 		<-p.audioChan
 	}
-
+	p.mutex.Lock()
 	return nil
 }
 
@@ -138,7 +148,10 @@ func (p *Player) readFileAudio() {
 	args := []string{"-loglevel", "error", "-i", p.filename}
 	args = append(args, "-ac", "2", "-ar", strconv.Itoa(gumble.AudioSampleRate), "-f", "s16le", "-")
 
-	cmd := exec.Command("ffmpeg", args...)
+	p.mutex.Lock()
+	ctx := p.ctx
+	p.mutex.Unlock()
+	cmd := exec.CommandContext(ctx, "ffmpeg", args...)
 	pipe, err := cmd.StdoutPipe()
 	if err != nil {
 		p.mutex.Lock()
@@ -171,15 +184,21 @@ func (p *Player) readFileAudio() {
 		case <-ticker.C:
 			n, err := io.ReadFull(pipe, byteBuffer)
 			if err != nil || n != len(byteBuffer) {
-				// File finished playing
+				select {
+				case <-p.stopChan:
+					cmd.Wait()
+					return
+				default:
+				}
+				// File finished playing.
 				p.mutex.Lock()
 				p.playing = false
-				if p.localPlayback != nil {
-					p.localPlayback(nil)
-				}
+				localPlayback := p.localPlayback
 				p.mutex.Unlock()
+				if localPlayback != nil {
+					localPlayback(nil)
+				}
 				cmd.Wait()
-				// Notify that file finished
 				p.reportError(errors.New("file playback finished"))
 				return
 			}