audio: Create an independent goroutine for enqueuing

audio/internal/driver/driver_android.go

@@ -182,7 +182,6 @@ import "C"
 
 import (
 	"errors"
-	"sync"
 	"unsafe"
 )
 
@@ -193,8 +192,8 @@ type Player struct {
 	audioTrack     C.jobject
 	buffer         []byte
 	bufferSize     int
-	m              sync.Mutex
 	chErr          chan error
+	chBuffer       chan []byte
 }
 
 func NewPlayer(sampleRate, channelNum, bytesPerSample int) (*Player, error) {
@@ -204,6 +203,7 @@ func NewPlayer(sampleRate, channelNum, bytesPerSample int) (*Player, error) {
 		bytesPerSample: bytesPerSample,
 		buffer:         []byte{},
 		chErr:          make(chan error),
+		chBuffer:       make(chan []byte),
 	}
 	if err := runOnJVM(func(vm, env, ctx uintptr) error {
 		audioTrack := C.jobject(nil)
@@ -219,20 +219,8 @@ func NewPlayer(sampleRate, channelNum, bytesPerSample int) (*Player, error) {
 	}); err != nil {
 		return nil, err
 	}
-	return p, nil
+	go func() {
-}
+		for bufInBytes := range p.chBuffer {
-
-func (p *Player) Proceed(data []byte) error {
-	select {
-	case err := <-p.chErr:
-		return err
-	default:
-	}
-	p.buffer = append(p.buffer, data...)
-	if len(p.buffer) < p.bufferSize {
-		return nil
-	}
-	bufInBytes := p.buffer[:p.bufferSize]
 			var bufInShorts []int16
 			if p.bytesPerSample == 2 {
 				bufInShorts = make([]int16, len(bufInBytes)/2)
@@ -240,10 +228,7 @@ func (p *Player) Proceed(data []byte) error {
 					bufInShorts[i] = int16(bufInBytes[2*i]) | (int16(bufInBytes[2*i+1]) << 8)
 				}
 			}
-	p.buffer = p.buffer[p.bufferSize:]
+
-	go func() {
-		p.m.Lock()
-		defer p.m.Unlock()
 			if err := runOnJVM(func(vm, env, ctx uintptr) error {
 				msg := (*C.char)(nil)
 				switch p.bytesPerSample {
@@ -262,8 +247,26 @@ func (p *Player) Proceed(data []byte) error {
 				return nil
 			}); err != nil {
 				p.chErr <- err
+				return
+			}
 		}
 	}()
+	return p, nil
+}
+
+func (p *Player) Proceed(data []byte) error {
+	select {
+	case err := <-p.chErr:
+		return err
+	default:
+	}
+	p.buffer = append(p.buffer, data...)
+	if len(p.buffer) < p.bufferSize {
+		return nil
+	}
+	buf := p.buffer[:p.bufferSize]
+	p.chBuffer <- buf
+	p.buffer = p.buffer[p.bufferSize:]
 	return nil
 }