win32 backend for low-level audio fixes

- fix deadlock with QAudioInput (win32) backend
- changed win32 backend to use QMutex lock
- setNotifyInterval(0) to disable notify() signal

Reviewed-by:Derick Hawcroft

1 files changed, 34 insertions, 37 deletions

diff --git a/src/multimedia/audio/qaudiooutput_win32_p.cpp b/src/multimedia/audio/qaudiooutput_win32_p.cpp
index b92565d..533583a 100644
--- a/src/multimedia/audio/qaudiooutput_win32_p.cpp
+++ b/src/multimedia/audio/qaudiooutput_win32_p.cpp
@@ -56,8 +56,6 @@
 
 QT_BEGIN_NAMESPACE
 
-static const int minimumIntervalTime = 50;
-
 QAudioOutputPrivate::QAudioOutputPrivate(const QByteArray &device, const QAudioFormat& audioFormat):
     settings(audioFormat)
 {
@@ -73,17 +71,15 @@ QAudioOutputPrivate::QAudioOutputPrivate(const QByteArray &device, const QAudioF
     audioSource = 0;
     pullMode = true;
     finished = false;
-    InitializeCriticalSection(&waveOutCriticalSection);
 }
 
 QAudioOutputPrivate::~QAudioOutputPrivate()
 {
-    EnterCriticalSection(&waveOutCriticalSection);
+    mutex.lock();
     finished = true;
-    LeaveCriticalSection(&waveOutCriticalSection);
+    mutex.unlock();
 
     close();
-    DeleteCriticalSection(&waveOutCriticalSection);
 }
 
 void CALLBACK QAudioOutputPrivate::waveOutProc( HWAVEOUT hWaveOut, UINT uMsg,
@@ -98,6 +94,8 @@ void CALLBACK QAudioOutputPrivate::waveOutProc( HWAVEOUT hWaveOut, UINT uMsg,
     if(!qAudio)
         return;
 
+    QMutexLocker(&qAudio->mutex);
+
     switch(uMsg) {
         case WOM_OPEN:
             qAudio->feedback();
@@ -105,16 +103,13 @@ void CALLBACK QAudioOutputPrivate::waveOutProc( HWAVEOUT hWaveOut, UINT uMsg,
         case WOM_CLOSE:
             return;
         case WOM_DONE:
-            EnterCriticalSection(&qAudio->waveOutCriticalSection);
             if(qAudio->finished || qAudio->buffer_size == 0 || qAudio->period_size == 0) {
-                LeaveCriticalSection(&qAudio->waveOutCriticalSection);
                 return;
 	    }
             qAudio->waveFreeBlockCount++;
             if(qAudio->waveFreeBlockCount >= qAudio->buffer_size/qAudio->period_size)
                 qAudio->waveFreeBlockCount = qAudio->buffer_size/qAudio->period_size;
             qAudio->feedback();
-            LeaveCriticalSection(&qAudio->waveOutCriticalSection);
             break;
         default:
             return;
@@ -150,8 +145,7 @@ void QAudioOutputPrivate::freeBlocks(WAVEHDR* blockArray)
     int count = buffer_size/period_size;
 
     for(int i = 0; i < count; i++) {
-        if (blocks->dwFlags & WHDR_PREPARED)
-            waveOutUnprepareHeader(hWaveOut,blocks, sizeof(WAVEHDR));
+        waveOutUnprepareHeader(hWaveOut,blocks, sizeof(WAVEHDR));
         blocks+=sizeof(WAVEHDR);
     }
     HeapFree(GetProcessHeap(), 0, blockArray);
@@ -226,9 +220,9 @@ bool QAudioOutputPrivate::open()
     }
     waveBlocks = allocateBlocks(period_size, buffer_size/period_size);
 
-    EnterCriticalSection(&waveOutCriticalSection);
+    mutex.lock();
     waveFreeBlockCount = buffer_size/period_size;
-    LeaveCriticalSection(&waveOutCriticalSection);
+    mutex.unlock();
 
     waveCurrentBlock = 0;
 
@@ -334,10 +328,7 @@ int QAudioOutputPrivate::bufferSize() const
 
 void QAudioOutputPrivate::setNotifyInterval(int ms)
 {
-    if(ms >= minimumIntervalTime)
-        intervalTime = ms;
-    else
-        intervalTime = minimumIntervalTime;
+    intervalTime = qMax(0, ms);
 }
 
 int QAudioOutputPrivate::notifyInterval() const
@@ -369,12 +360,12 @@ qint64 QAudioOutputPrivate::write( const char *data, qint64 len )
     int remain;
     current = &waveBlocks[waveCurrentBlock];
     while(l > 0) {
-        EnterCriticalSection(&waveOutCriticalSection);
+        mutex.lock();
         if(waveFreeBlockCount==0) {
-            LeaveCriticalSection(&waveOutCriticalSection);
+            mutex.unlock();
             break;
         }
-        LeaveCriticalSection(&waveOutCriticalSection);
+        mutex.unlock();
 
         if(current->dwFlags & WHDR_PREPARED)
             waveOutUnprepareHeader(hWaveOut, current, sizeof(WAVEHDR));
@@ -391,15 +382,13 @@ qint64 QAudioOutputPrivate::write( const char *data, qint64 len )
         waveOutPrepareHeader(hWaveOut, current, sizeof(WAVEHDR));
         waveOutWrite(hWaveOut, current, sizeof(WAVEHDR));
 
-        EnterCriticalSection(&waveOutCriticalSection);
+        mutex.lock();
         waveFreeBlockCount--;
-        LeaveCriticalSection(&waveOutCriticalSection);
 #ifdef DEBUG_AUDIO
-        EnterCriticalSection(&waveOutCriticalSection);
         qDebug("write out l=%d, waveFreeBlockCount=%d",
                 current->dwBufferLength,waveFreeBlockCount);
-        LeaveCriticalSection(&waveOutCriticalSection);
 #endif
+        mutex.unlock();
         totalTimeValue += current->dwBufferLength;
         waveCurrentBlock++;
         waveCurrentBlock %= buffer_size/period_size;
@@ -454,7 +443,7 @@ void QAudioOutputPrivate::feedback()
 
 bool QAudioOutputPrivate::deviceReady()
 {
-    if(deviceState == QAudio::StoppedState)
+    if(deviceState == QAudio::StoppedState || deviceState == QAudio::SuspendedState)
         return false;
 
     if(pullMode) {
@@ -468,14 +457,16 @@ bool QAudioOutputPrivate::deviceReady()
 	    startup = true;
 
 	bool full=false;
-	EnterCriticalSection(&waveOutCriticalSection);
+
+        mutex.lock();
 	if(waveFreeBlockCount==0) full = true;
-	LeaveCriticalSection(&waveOutCriticalSection);
+        mutex.unlock();
+
 	if (full){
 #ifdef DEBUG_AUDIO
             qDebug() << "Skipping data as unable to write";
 #endif
-	    if((timeStamp.elapsed() + elapsedTimeOffset) > intervalTime ) {
+	    if(intervalTime && (timeStamp.elapsed() + elapsedTimeOffset) > intervalTime ) {
                 emit notify();
 		elapsedTimeOffset = timeStamp.elapsed() + elapsedTimeOffset - intervalTime;
 		timeStamp.restart();
@@ -505,12 +496,14 @@ bool QAudioOutputPrivate::deviceReady()
             bytesAvailable = bytesFree();
 
             int check = 0;
-            EnterCriticalSection(&waveOutCriticalSection);
+
+            mutex.lock();
             check = waveFreeBlockCount;
-            LeaveCriticalSection(&waveOutCriticalSection);
+            mutex.unlock();
+
             if(check == buffer_size/period_size) {
-                errorState = QAudio::UnderrunError;
                 if (deviceState != QAudio::IdleState) {
+                    errorState = QAudio::UnderrunError;
                     deviceState = QAudio::IdleState;
                     emit stateChanged(deviceState);
                 }
@@ -522,19 +515,23 @@ bool QAudioOutputPrivate::deviceReady()
         }
     } else {
         int buffered;
-	EnterCriticalSection(&waveOutCriticalSection);
+
+        mutex.lock();
 	buffered = waveFreeBlockCount;
-	LeaveCriticalSection(&waveOutCriticalSection);
-        errorState = QAudio::UnderrunError;
+        mutex.unlock();
+
         if (buffered >= buffer_size/period_size && deviceState == QAudio::ActiveState) {
-            deviceState = QAudio::IdleState;
-            emit stateChanged(deviceState);
+            if (deviceState != QAudio::IdleState) {
+                errorState = QAudio::UnderrunError;
+                deviceState = QAudio::IdleState;
+                emit stateChanged(deviceState);
+            }
         }
     }
     if(deviceState != QAudio::ActiveState && deviceState != QAudio::IdleState)
         return true;
 
-    if((timeStamp.elapsed() + elapsedTimeOffset) > intervalTime) {
+    if(intervalTime && (timeStamp.elapsed() + elapsedTimeOffset) > intervalTime) {
         emit notify();
 	elapsedTimeOffset = timeStamp.elapsed() + elapsedTimeOffset - intervalTime;
         timeStamp.restart();