* Remove a short-lived hack (hours?) and replace it with a

PaStreamFinishedCallback which is called anytime a PaCallback is exited with
  anything other than 0. (normal operation)  paStreamFinishedCallback handles
  stopping the audio stream when we've run to the end of the current selection
  or the stream is stopped.
* Add framesPerBuffer to paCallback debug output in preperation for dynamic
  buffers.
* Set paPrimeOutputBuffersUsingStreamCallback in Pa_OpenStream to prime the
  output buffer using the callback rather than initing with empty space which
  is the default.
* Indent paCallback decleration another level.

Originally committed to SVN as r2807.

aegisub/src/audio_player_portaudio2.cpp

@@ -94,14 +94,15 @@ int PortAudioPlayer::paCallback(const void *inputBuffer, void *outputBuffer, uns
 	AudioProvider *provider = player->GetProvider();
 
 #ifdef PORTAUDIO2_DEBUG
-	printf("paCallBack: playPos: %lld  startPos: %lld  paStart: %f Pa_GetStreamTime: %f  AdcTime: %f  DacTime: %f  CPU: %f\n", 
+	printf("paCallBack: playPos: %lld  startPos: %lld  paStart: %f Pa_GetStreamTime: %f  AdcTime: %f  DacTime: %f  framesPerBuffer: %lu  CPU: %f\n", 
 	player->playPos, player->startPos, player->paStart, Pa_GetStreamTime(player->stream), 
-	timeInfo->inputBufferAdcTime, timeInfo->outputBufferDacTime,  Pa_GetStreamCpuLoad(player->stream));
+	timeInfo->inputBufferAdcTime, timeInfo->outputBufferDacTime,  framesPerBuffer, Pa_GetStreamCpuLoad(player->stream));
 #endif
 
 	// Calculate how much left
 	int64_t lenAvailable = (player->endPos - player->playPos) > 0 ? framesPerBuffer : 0;
 
+
 	// Play something
 	if (lenAvailable > 0) {
 		provider->GetAudioWithVolume(outputBuffer, player->playPos, lenAvailable, player->GetVolume());
@@ -112,19 +113,17 @@ int PortAudioPlayer::paCallback(const void *inputBuffer, void *outputBuffer, uns
 		// Continue as normal
 		return 0;
 	}
-	else {
-		// Set the end position to be less then the current play position.
-		player->endPos = player->endPos - (framesPerBuffer + 8192);
 
-		// Abort stream and stop the callback.
-		return paAbort;
-	}
+	// Abort stream and stop the callback.
+	return paAbort;
 }
 
 
 ////////
 // Play
 void PortAudioPlayer::Play(int64_t start,int64_t count) {
+	PaError err;
+
 	// Stop if it's already playing
 	wxMutexLocker locker(PAMutex);
 
@@ -135,7 +134,16 @@ void PortAudioPlayer::Play(int64_t start,int64_t count) {
 
 	// Start playing
 	if (!playing) {
-		PaError err = Pa_StartStream(stream);
+
+		err = Pa_SetStreamFinishedCallback(stream, paStreamFinishedCallback);
+
+		if (err != paNoError) {
+			wxLogDebug(_T("PortAudioPlayer::Play Could not set FinishedCallback\n"));
+			return;
+		}
+
+		err = Pa_StartStream(stream);
+
 		if (err != paNoError) {
 			return;
 		}
@@ -164,6 +172,21 @@ void PortAudioPlayer::Stop(bool timerToo) {
 	}
 }
 
+//////////////////////////////////////////////
+// Called when the callback has finished.
+
+void PortAudioPlayer::paStreamFinishedCallback(void *userData) {
+    PortAudioPlayer *player = (PortAudioPlayer *) userData;
+
+	player->playing = false;
+
+	if (player->displayTimer) {
+		player->displayTimer->Stop();
+	}
+
+	wxLogDebug(_T("PortAudioPlayer::paStreamFinishedCallback Stopping stream."));
+}
+
 
 ///////////////
 // Open stream
@@ -191,7 +214,7 @@ void PortAudioPlayer::OpenStream() {
 	wxLogDebug(_T("PortAudioPlayer::OpenStream Output channels: %d, Latency: %f  Sample Rate: %ld\n"),
 	pa_output_p.channelCount, pa_output_p.suggestedLatency, pa_output_p.sampleFormat);
 
-	PaError err = Pa_OpenStream(&stream, NULL, &pa_output_p, provider->GetSampleRate(), 256, paClipOff, paCallback, this);
+	PaError err = Pa_OpenStream(&stream, NULL, &pa_output_p, provider->GetSampleRate(), 256, paPrimeOutputBuffersUsingStreamCallback, paCallback, this);
 
 	if (err != paNoError) {
 
@@ -213,6 +236,7 @@ void PortAudioPlayer::CloseStream() {
 	} catch (...) {}
 }
 
+
 ////////////////////////
 /// Get current stream position.
 int64_t PortAudioPlayer::GetCurrentPosition()

aegisub/src/audio_player_portaudio2.h

@@ -65,15 +65,17 @@ private:
 	void *stream;
 	PaTime paStart;
 
-static int paCallback(
-	const void *inputBuffer,
-	void *outputBuffer,
-	unsigned long framesPerBuffer,
-	const PaStreamCallbackTimeInfo*
-	timeInfo,
-	PaStreamCallbackFlags
-	statusFlags,
-	void *userData);
+	static int paCallback(
+		const void *inputBuffer,
+		void *outputBuffer,
+		unsigned long framesPerBuffer,
+		const PaStreamCallbackTimeInfo*
+		timeInfo,
+		PaStreamCallbackFlags
+		statusFlags,
+		void *userData);
+
+	static void paStreamFinishedCallback(void *userData);
 
 public:
 	PortAudioPlayer();