audio: Add Player.Close (#194)

examples/audio/main.go

@@ -78,6 +78,14 @@ func playerBarRect() (x, y, w, h int) {
 	return
 }
 
+type SEStream struct {
+	*bytes.Reader
+}
+
+func (s *SEStream) Close() error {
+	return nil
+}
+
 func (p *Player) updateSE() error {
 	if seStream == nil {
 		return nil
@@ -99,7 +107,7 @@ func (p *Player) updateSE() error {
 		}
 		seBuffer = b
 	}
-	sePlayer, err := audioContext.NewPlayer(bytes.NewReader(seBuffer))
+	sePlayer, err := audioContext.NewPlayer(&SEStream{bytes.NewReader(seBuffer)})
 	if err != nil {
 		return err
 	}
@@ -168,6 +176,10 @@ func (p *Player) updateBar() error {
 	return p.audioPlayer.Seek(pos)
 }
 
+func (p *Player) close() error {
+	return p.audioPlayer.Close()
+}
+
 func update(screen *ebiten.Image) error {
 	audioContext.Update()
 	if musicPlayer == nil {
@@ -272,4 +284,9 @@ func main() {
 	if err := ebiten.Run(update, screenWidth, screenHeight, 2, "Audio (Ebiten Demo)"); err != nil {
 		log.Fatal(err)
 	}
+	if musicPlayer != nil {
+		if err := musicPlayer.close(); err != nil {
+			log.Fatal(err)
+		}
+	}
 }

examples/sinewave/main.go

@@ -76,6 +76,10 @@ func (s *stream) Seek(offset int64, whence int) (int64, error) {
 	return s.position, nil
 }
 
+func (s *stream) Close() error {
+	return nil
+}
+
 var player *audio.Player
 
 func update(screen *ebiten.Image) error {

exp/audio/audio.go

@@ -17,6 +17,7 @@ package audio
 import (
 	"fmt"
 	"io"
+	"runtime"
 	"sync"
 	"time"
 
@@ -148,9 +149,14 @@ func (c *Context) SampleRate() int {
 	return c.sampleRate
 }
 
+type ReadSeekCloser interface {
+	io.ReadSeeker
+	io.Closer
+}
+
 type Player struct {
 	context *Context
-	src     io.ReadSeeker
+	src     ReadSeekCloser
 	buf     []byte
 	pos     int64
 	volume  float64
@@ -162,7 +168,7 @@ type Player struct {
 //
 // src's format must be linear PCM (16bits, 2 channel stereo, little endian)
 // without a header (e.g. RIFF header).
-func (c *Context) NewPlayer(src io.ReadSeeker) (*Player, error) {
+func (c *Context) NewPlayer(src ReadSeekCloser) (*Player, error) {
 	c.Lock()
 	defer c.Unlock()
 	p := &Player{
@@ -177,9 +183,15 @@ func (c *Context) NewPlayer(src io.ReadSeeker) (*Player, error) {
 		return nil, err
 	}
 	p.pos = pos
+	runtime.SetFinalizer(p, (*Player).Close)
 	return p, nil
 }
 
+func (p *Player) Close() error {
+	runtime.SetFinalizer(p, nil)
+	return p.src.Close()
+}
+
 func (p *Player) readToBuffer(length int) (int, error) {
 	bb := make([]byte, length)
 	n, err := p.src.Read(bb)

exp/audio/vorbis/stream.go

@@ -32,6 +32,11 @@ func (s *Stream) Seek(offset int64, whence int) (int64, error) {
 	return s.buf.Seek(offset, whence)
 }
 
+func (s *Stream) Close() error {
+	s.buf = nil
+	return nil
+}
+
 func (s *Stream) Len() time.Duration {
 	const bytesPerSample = 4
 	return time.Duration(s.buf.Len()/bytesPerSample) * time.Second / time.Duration(s.sampleRate)

exp/audio/wav/decode.go

@@ -43,6 +43,11 @@ func (s *Stream) Seek(offset int64, whence int) (int64, error) {
 	return s.buf.Seek(offset, whence)
 }
 
+func (s *Stream) Close() error {
+	s.buf = nil
+	return nil
+}
+
 func (s *Stream) Len() time.Duration {
 	const bytesPerSample = 4
 	return time.Duration(s.buf.Len()/bytesPerSample) * time.Second / time.Duration(s.sampleRate)