audio: Remove returning value from startPlaying

exp/audio/audio.go

@@ -105,11 +105,10 @@ func (s *mixedPlayersStream) Read(b []byte) (int, error) {
 // TODO: Enable to specify the format like Mono8?
 
 type Context struct {
-	sampleRate  int
+	sampleRate int
-	stream      *mixedPlayersStream
+	stream     *mixedPlayersStream
-	players     map[*Player]struct{}
+	players    map[*Player]struct{}
-	innerPlayer *player
+	frames     int
-	frames      int
 	sync.Mutex
 }
 
@@ -122,11 +121,9 @@ func NewContext(sampleRate int) *Context {
 	c.stream = &mixedPlayersStream{
 		context: c,
 	}
-	p, err := startPlaying(c.stream, c.sampleRate)
+	if err := startPlaying(c.stream, c.sampleRate); err != nil {
-	if err != nil {
 		panic(fmt.Sprintf("audio: NewContext error: %v", err))
 	}
-	c.innerPlayer = p
 	return c
 }
 

exp/audio/audio_openal.go

@@ -40,13 +40,13 @@ type player struct {
 	isClosed   bool
 }
 
-func startPlaying(src io.Reader, sampleRate int) (*player, error) {
+func startPlaying(src io.Reader, sampleRate int) error {
 	if e := al.OpenDevice(); e != nil {
-		return nil, fmt.Errorf("audio: OpenAL initialization failed: %v", e)
+		return fmt.Errorf("audio: OpenAL initialization failed: %v", e)
 	}
 	s := al.GenSources(1)
 	if err := al.Error(); err != 0 {
-		panic(fmt.Sprintf("audio: al.GenSources error: %d", err))
+		return fmt.Errorf("audio: al.GenSources error: %d", err)
 	}
 	p := &player{
 		alSource:   s[0],
@@ -55,10 +55,7 @@ func startPlaying(src io.Reader, sampleRate int) (*player, error) {
 		sampleRate: sampleRate,
 	}
 	runtime.SetFinalizer(p, (*player).close)
-	if err := p.start(); err != nil {
+	return p.start()
-		return nil, err
-	}
-	return p, nil
 }
 
 const (

exp/audio/audio_windows.go

@@ -37,6 +37,8 @@ type header struct {
 	waveHdr    C.WAVEHDR
 }
 
+// TODO: Reduce panics and use errors instead
+
 func newHeader(waveOut C.HWAVEOUT, bufferSize int) header {
 	// NOTE: This is never freed so far.
 	buf := C.malloc(C.size_t(bufferSize))
@@ -74,10 +76,7 @@ func releaseSemaphore() {
 	<-sem
 }
 
-type player struct {
+func startPlaying(src io.Reader, sampleRate int) error {
-}
-
-func startPlaying(src io.Reader, sampleRate int) (*player, error) {
 	const numBlockAlign = channelNum * bitsPerSample / 8
 	f := C.WAVEFORMATEX{
 		wFormatTag:      C.WAVE_FORMAT_PCM,
@@ -89,7 +88,7 @@ func startPlaying(src io.Reader, sampleRate int) (*player, error) {
 	}
 	var w C.HWAVEOUT
 	if err := C.waveOutOpen2(&w, &f); err != C.MMSYSERR_NOERROR {
-		panic(fmt.Sprintf("audio: waveOutOpen error: %d", err))
+		return fmt.Errorf("audio: waveOutOpen error: %d", err)
 	}
 	go func() {
 		const bufferSize = 1024
@@ -123,5 +122,5 @@ func startPlaying(src io.Reader, sampleRate int) (*player, error) {
 		}
 		// TODO: Finalize the wave handler
 	}()
-	return &player{}, nil
+	return nil
 }