audio/internal/readerdriver: Reimplement Windows driver with multiple waveOutOpen

This improves the result of examples/piano significantly.

The issue of mutexes (#1652) is also resolved by this new
implementation.

Closes #1652
Closes #1653
This commit is contained in:
Hajime Hoshi 2021-05-28 22:27:18 +09:00
parent 3e113e69e8
commit 98bfe5a692
2 changed files with 310 additions and 279 deletions

View File

@ -55,7 +55,10 @@ func (h *header) Write(data []byte) error {
data = append(data, make([]byte, n)...)
}
copy(h.buffer, data)
return waveOutWrite(h.waveOut, h.waveHdr)
if err := waveOutWrite(h.waveOut, h.waveHdr); err != nil {
return err
}
return nil
}
func (h *header) IsQueued() bool {
@ -81,7 +84,6 @@ func NewContext(sampleRate, channelNum, bitDepthInBytes int) (Context, chan stru
channelNum: channelNum,
bitDepthInBytes: bitDepthInBytes,
}
thePlayers.setContext(c)
return c, ready, nil
}
@ -94,145 +96,54 @@ func (c *context) Resume() error {
}
type players struct {
context *context
players map[*playerImpl]struct{}
buf []byte
err error
waveOut uintptr
headers []*header
cond *sync.Cond
players map[uintptr]*playerImpl
toResume map[*playerImpl]struct{}
cond *sync.Cond
}
func (p *players) setContext(context *context) {
func (p *players) add(player *playerImpl, waveOut uintptr) {
p.cond.L.Lock()
defer p.cond.L.Unlock()
p.context = context
}
func (p *players) add(player *playerImpl) error {
p.cond.L.Lock()
defer p.cond.L.Unlock()
if p.err != nil {
return p.err
}
if p.players == nil {
p.players = map[*playerImpl]struct{}{}
p.players = map[uintptr]*playerImpl{}
}
p.players[player] = struct{}{}
p.cond.Signal()
if p.waveOut != 0 {
return nil
runLoop := len(p.players) == 0
p.players[waveOut] = player
if runLoop {
// Use the only one loop. Windows' context switching is not efficent and
// using too many goroutines might be problematic.
go p.loop()
}
numBlockAlign := p.context.channelNum * p.context.bitDepthInBytes
f := &waveformatex{
wFormatTag: waveFormatPCM,
nChannels: uint16(p.context.channelNum),
nSamplesPerSec: uint32(p.context.sampleRate),
nAvgBytesPerSec: uint32(p.context.sampleRate * numBlockAlign),
wBitsPerSample: uint16(p.context.bitDepthInBytes * 8),
nBlockAlign: uint16(numBlockAlign),
}
w, err := waveOutOpen(f, waveOutOpenCallback)
const elementNotFound = 1168
if e, ok := err.(*winmmError); ok && e.errno == elementNotFound {
// TODO: No device was found. Return the dummy device (hajimehoshi/oto#77).
// TODO: Retry to open the device when possible.
return err
}
if err != nil {
return err
}
p.waveOut = w
p.headers = make([]*header, 0, 4)
for len(p.headers) < cap(p.headers) {
h, err := newHeader(p.waveOut, headerBufferSize)
if err != nil {
return err
}
p.headers = append(p.headers, h)
}
if err := p.readAndWriteBuffers(); err != nil {
return err
}
go p.loop()
return nil
}
func (p *players) remove(player *playerImpl) error {
func (p *players) remove(waveOut uintptr) {
p.cond.L.Lock()
defer p.cond.L.Unlock()
return p.removeImpl(player)
}
func (p *players) removeImpl(player *playerImpl) error {
if p.err != nil {
return p.err
pl, ok := p.players[waveOut]
if !ok {
return
}
delete(p.players, player)
return nil
}
delete(p.players, waveOut)
delete(p.toResume, pl)
func (p *players) shouldWait() bool {
if p.waveOut == 0 {
return false
}
if len(p.players) == 0 {
return true
}
if len(p.buf) < headerBufferSize*len(p.headers) {
return false
}
for _, h := range p.headers {
if !h.IsQueued() {
return false
}
}
return true
}
func (p *players) loop() {
for {
p.cond.L.Lock()
for p.shouldWait() {
p.cond.Wait()
}
if p.waveOut == 0 {
p.cond.L.Unlock()
return
}
if err := p.readAndWriteBuffers(); err != nil {
p.err = err
p.cond.L.Unlock()
break
}
p.cond.L.Unlock()
}
p.cond.Signal()
}
func (p *players) suspend() error {
p.cond.L.Lock()
defer p.cond.L.Unlock()
if p.waveOut == 0 {
return nil
}
if err := waveOutPause(p.waveOut); err != nil {
return err
for _, pl := range p.players {
if !pl.IsPlaying() {
continue
}
pl.Pause()
if p.toResume == nil {
p.toResume = map[*playerImpl]struct{}{}
}
p.toResume[pl] = struct{}{}
}
return nil
}
@ -241,128 +152,47 @@ func (p *players) resume() error {
p.cond.L.Lock()
defer p.cond.L.Unlock()
if p.waveOut == 0 {
return nil
for pl := range p.toResume {
pl.Play()
delete(p.toResume, pl)
}
if err := waveOutRestart(p.waveOut); err != nil {
return err
}
p.cond.Signal()
return nil
}
var waveOutOpenCallback = windows.NewCallbackCDecl(func(hwo, uMsg, dwInstance, dwParam1, dwParam2 uintptr) uintptr {
const womDone = 0x3bd
if uMsg != womDone {
return 0
}
thePlayers.cond.Signal()
return 0
})
func (p *players) readAndWriteBuffers() error {
func (p *players) shouldWait() bool {
if len(p.players) == 0 {
return nil
return false
}
headerNum := 0
for _, h := range p.headers {
if h.IsQueued() {
continue
for _, pl := range p.players {
if pl.canProceed() {
return false
}
headerNum++
}
if headerNum == 0 {
return nil
return true
}
func (p *players) wait() bool {
p.cond.L.Lock()
defer p.cond.L.Unlock()
for p.shouldWait() {
p.cond.Wait()
}
return len(p.players) > 0
}
if n := headerBufferSize*headerNum - len(p.buf); n > 0 {
// Do mixing of the current players instead of mixing on the OS side.
// Apparently, mixing on the Go side is more effient and requires less buffers.
//
// waveOutSetVolume is not used since it doesn't work correctly in some environments.
var volumes []float64
var bufs [][]byte
for pl := range p.players {
buf := make([]byte, n)
n := pl.read(buf)
bufs = append(bufs, buf[:n])
volumes = append(volumes, pl.Volume())
func (p *players) loop() {
for {
if !p.wait() {
return
}
buf := make([]byte, n)
switch p.context.bitDepthInBytes {
case 1:
const (
max = 127
min = -128
offset = 128
)
for i := 0; i < n; i++ {
var x int16
for j, b := range bufs {
if len(b) <= i {
continue
}
xx := int16(b[i]) - offset
x += int16(float64(xx) * volumes[j])
}
if x > max {
x = max
}
if x < min {
x = min
}
buf[i] = byte(x + offset)
}
case 2:
const (
max = (1 << 15) - 1
min = -(1 << 15)
)
for i := 0; i < n/2; i++ {
var x int32
for j, b := range bufs {
if len(b) <= 2*i {
continue
}
xx := int32(int16(b[2*i]) | (int16(b[2*i+1]) << 8))
x += int32(float64(xx) * volumes[j])
}
if x > max {
x = max
}
if x < min {
x = min
}
buf[2*i] = byte(x)
buf[2*i+1] = byte(x >> 8)
}
p.cond.L.Lock()
for _, pl := range p.players {
pl.readAndWriteBuffer()
}
p.buf = append(p.buf, buf...)
p.cond.L.Unlock()
}
for _, h := range p.headers {
if len(p.buf) < headerBufferSize {
break
}
if h.IsQueued() {
continue
}
if err := h.Write(p.buf[:headerBufferSize]); err != nil {
// This error can happen when e.g. a new HDMI connection is detected (hajimehoshi/oto#51).
const errorNotFound = 1168
if werr := err.(*winmmError); werr.fname == "waveOutWrite" && werr.errno == errorNotFound {
// TODO: Retry later.
}
return err
}
p.buf = p.buf[headerBufferSize:]
}
return nil
}
var thePlayers = players{
@ -377,7 +207,9 @@ type playerImpl struct {
context *context
src io.Reader
err error
waveOut uintptr
state playerState
headers []*header
buf []byte
eof bool
volume float64
@ -404,7 +236,6 @@ func (p *player) Err() error {
func (p *playerImpl) Err() error {
p.m.Lock()
defer p.m.Unlock()
return p.err
}
@ -434,6 +265,44 @@ func (p *playerImpl) playImpl() {
return
}
if p.waveOut == 0 {
numBlockAlign := p.context.channelNum * p.context.bitDepthInBytes
f := &waveformatex{
wFormatTag: waveFormatPCM,
nChannels: uint16(p.context.channelNum),
nSamplesPerSec: uint32(p.context.sampleRate),
nAvgBytesPerSec: uint32(p.context.sampleRate * numBlockAlign),
wBitsPerSample: uint16(p.context.bitDepthInBytes * 8),
nBlockAlign: uint16(numBlockAlign),
}
w, err := waveOutOpen(f, waveOutOpenCallback)
const elementNotFound = 1168
if e, ok := err.(*winmmError); ok && e.errno == elementNotFound {
// TODO: No device was found. Return the dummy device (hajimehoshi/oto#77).
// TODO: Retry to open the device when possible.
p.setErrorImpl(err)
return
}
if err != nil {
p.setErrorImpl(err)
return
}
p.waveOut = w
p.headers = make([]*header, 0, 6)
for len(p.headers) < cap(p.headers) {
h, err := newHeader(p.waveOut, headerBufferSize)
if err != nil {
p.setErrorImpl(err)
return
}
p.headers = append(p.headers, h)
}
thePlayers.add(p, p.waveOut)
}
buf := make([]byte, p.context.maxBufferSize())
for len(p.buf) < p.context.maxBufferSize() {
n, err := p.src.Read(buf)
@ -452,21 +321,39 @@ func (p *playerImpl) playImpl() {
return
}
// Set the state before adding the player so that the audio loop can start to play it immediately.
// This is a little tricky since this depends on the timing of Signal().
// Set the state first as readAndWriteBufferImpl checks the current player state.
p.state = playerPlay
// thePlayers can has another mutex, and double mutex might introduce a deadlock.
p.m.Unlock()
err := thePlayers.add(p)
p.m.Lock()
// Call readAndWriteBufferImpl to ensure at least one header is queued.
p.readAndWriteBufferImpl()
if err != nil {
if err := waveOutRestart(p.waveOut); err != nil {
p.setErrorImpl(err)
return
}
// Do not create the player's own loop. Scheduling on Winodws is inefficient compared to the other OSes.
// Switching goroutines is very inefficient on Windows. Avoid a dedicated goroutine for a player.
}
func volumeForWinAPI(v float64) uint32 {
u32 := uint32(0xffff * v)
return (u32 << 16) | u32
}
func (p *playerImpl) queuedHeadersNum() int {
var c int
for _, h := range p.headers {
if h.IsQueued() {
c++
}
}
return c
}
func (p *playerImpl) canProceed() bool {
p.m.Lock()
defer p.m.Unlock()
return p.queuedHeadersNum() < len(p.headers) && p.state == playerPlay
}
func (p *player) Pause() {
@ -486,6 +373,17 @@ func (p *playerImpl) pauseImpl() {
if p.state != playerPlay {
return
}
if p.waveOut == 0 {
return
}
// waveOutPause never return when there is no queued header.
if p.queuedHeadersNum() > 0 {
if err := waveOutPause(p.waveOut); err != nil {
p.setErrorImpl(err)
return
}
}
p.state = playerPaused
}
@ -507,6 +405,38 @@ func (p *playerImpl) resetImpl() {
if p.state == playerClosed {
return
}
if p.waveOut == 0 {
return
}
// waveOutReset and waveOutPause never return when there is no queued header.
if p.queuedHeadersNum() > 0 {
err := waveOutReset(p.waveOut)
if err != nil {
p.setErrorImpl(err)
return
}
err = waveOutPause(p.waveOut)
if err != nil {
p.setErrorImpl(err)
return
}
}
// Now all the headers are WHDR_DONE. Recreate the headers.
for i, h := range p.headers {
if err := h.Close(); err != nil {
p.setErrorImpl(err)
return
}
h, err := newHeader(p.waveOut, headerBufferSize)
if err != nil {
p.setErrorImpl(err)
return
}
p.headers[i] = h
}
p.state = playerPaused
p.buf = p.buf[:0]
@ -566,59 +496,142 @@ func (p *playerImpl) Close() error {
func (p *playerImpl) closeImpl() error {
p.state = playerClosed
if p.waveOut != 0 {
for _, h := range p.headers {
if err := h.Close(); err != nil && p.err == nil {
p.err = err
}
}
p.headers = p.headers[:0]
if err := waveOutClose(p.waveOut); err != nil && p.err == nil {
p.err = err
}
p.m.Unlock()
err := thePlayers.remove(p)
p.m.Lock()
// This player's lock might block thePlayer's lock. Unlock this first.
p.m.Unlock()
thePlayers.remove(p.waveOut)
p.m.Lock()
if err != nil && p.err == nil {
p.err = err
p.waveOut = 0
}
return p.err
}
func (p *playerImpl) setError(err error) {
var waveOutOpenCallback = windows.NewCallbackCDecl(func(hwo, uMsg, dwInstance, dwParam1, dwParam2 uintptr) uintptr {
const womDone = 0x3bd
if uMsg != womDone {
return 0
}
thePlayers.cond.Signal()
return 0
})
func (p *playerImpl) readAndWriteBuffer() {
p.m.Lock()
defer p.m.Unlock()
p.setErrorImpl(err)
p.readAndWriteBufferImpl()
}
func (p *playerImpl) readAndWriteBufferImpl() {
if p.state != playerPlay {
return
}
if len(p.buf) < p.context.maxBufferSize() && !p.eof {
buf := make([]byte, p.context.maxBufferSize())
n, err := p.src.Read(buf)
if err != nil && err != io.EOF {
p.setErrorImpl(err)
return
}
p.buf = append(p.buf, buf[:n]...)
if err == io.EOF && len(p.buf) == 0 {
p.eof = true
}
}
if len(p.buf) > 0 {
for _, h := range p.headers {
if h.IsQueued() {
continue
}
n := headerBufferSize
if n > len(p.buf) {
n = len(p.buf)
}
buf := p.buf[:n]
// Adjust the volume
if p.volume < 1 {
switch p.context.bitDepthInBytes {
case 1:
const (
max = 127
min = -128
offset = 128
)
for i, b := range buf {
x := int16(b) - offset
x = int16(float64(x) * p.volume)
if x > max {
x = max
}
if x < min {
x = min
}
buf[i] = byte(x + offset)
}
case 2:
const (
max = (1 << 15) - 1
min = -(1 << 15)
)
for i := 0; i < n/2; i++ {
x := int32(int16(buf[2*i]) | (int16(buf[2*i+1]) << 8))
x = int32(float64(x) * p.volume)
if x > max {
x = max
}
if x < min {
x = min
}
buf[2*i] = byte(x)
buf[2*i+1] = byte(x >> 8)
}
}
}
if err := h.Write(buf); err != nil {
// This error can happen when e.g. a new HDMI connection is detected (hajimehoshi/oto#51).
const errorNotFound = 1168
if werr := err.(*winmmError); werr.fname == "waveOutWrite" {
switch {
case werr.mmresult == mmsyserrNomem:
continue
case werr.errno == errorNotFound:
// TODO: Retry later.
}
}
p.setErrorImpl(err)
return
}
p.buf = p.buf[n:]
// 4 is an arbitrary number that doesn't cause a problem at examples/piano (#1653).
if p.queuedHeadersNum() >= 4 {
break
}
}
}
if p.queuedHeadersNum() == 0 && p.eof {
p.pauseImpl()
}
}
func (p *playerImpl) setErrorImpl(err error) {
p.err = err
p.closeImpl()
}
func (p *playerImpl) read(buf []byte) int {
p.m.Lock()
defer p.m.Unlock()
if p.state != playerPlay {
return 0
}
if len(p.buf) == 0 && p.eof {
p.pauseImpl()
return 0
}
if len(p.buf) < p.context.maxBufferSize() {
buf := make([]byte, p.context.maxBufferSize())
n, err := p.src.Read(buf)
if err != nil && err != io.EOF {
p.setErrorImpl(err)
return len(buf)
}
p.buf = append(p.buf, buf[:n]...)
if err == io.EOF {
p.eof = true
}
}
bytesPerSample := p.context.channelNum * p.context.bitDepthInBytes
n := len(p.buf) / bytesPerSample * bytesPerSample
n = copy(buf, p.buf[:n])
p.buf = p.buf[n:]
return n
}

View File

@ -31,6 +31,7 @@ var (
procWaveOutClose = winmm.NewProc("waveOutClose")
procWaveOutPause = winmm.NewProc("waveOutPause")
procWaveOutPrepareHeader = winmm.NewProc("waveOutPrepareHeader")
procWaveOutReset = winmm.NewProc("waveOutReset")
procWaveOutRestart = winmm.NewProc("waveOutRestart")
procWaveOutUnprepareHeader = winmm.NewProc("waveOutUnprepareHeader")
procWaveOutWrite = winmm.NewProc("waveOutWrite")
@ -202,6 +203,23 @@ func waveOutPrepareHeader(hwo uintptr, pwh *wavehdr) error {
return nil
}
func waveOutReset(hwo uintptr) error {
r, _, e := procWaveOutReset.Call(hwo)
if e.(windows.Errno) != 0 {
return &winmmError{
fname: "waveOutReset",
errno: e.(windows.Errno),
}
}
if mmresult(r) != mmsyserrNoerror {
return &winmmError{
fname: "waveOutReset",
mmresult: mmresult(r),
}
}
return nil
}
func waveOutRestart(hwo uintptr) error {
r, _, e := procWaveOutRestart.Call(hwo)
if e.(windows.Errno) != 0 {