From 3632ce6df5d3c948f5e4c603c48f2d3c4e190eca Mon Sep 17 00:00:00 2001
From: skidau <skidau@gmail.com>
Date: Fri, 11 Jan 2013 19:42:03 +1100
Subject: [PATCH] Removed the synchronisation between the CPU thread and the
 audio thread. Added code to detect and resume from buffer underruns. Disabled
 the ability to change the DPL2 option after the game has started. Fixed a
 memory leak that occurred in the DPL2 decoder. Fixed the OSX build.

---
 Source/Core/AudioCommon/Src/OpenALStream.cpp | 26 ++++++++++++++------
 Source/Core/DolphinWX/Src/ConfigMain.cpp     |  1 +
 2 files changed, 20 insertions(+), 7 deletions(-)

diff --git a/Source/Core/AudioCommon/Src/OpenALStream.cpp b/Source/Core/AudioCommon/Src/OpenALStream.cpp
index 8fb1f1b2c5..1895cd2199 100644
--- a/Source/Core/AudioCommon/Src/OpenALStream.cpp
+++ b/Source/Core/AudioCommon/Src/OpenALStream.cpp
@@ -79,7 +79,6 @@ void OpenALStream::Stop()
 	threadData = 1;
 	// kick the thread if it's waiting
 	soundSyncEvent.Set();
-	mainSyncEvent.Set();
 
 	soundTouch.clear();
 
@@ -112,7 +111,6 @@ void OpenALStream::SetVolume(int volume)
 void OpenALStream::Update()
 {
 	soundSyncEvent.Set();
-	mainSyncEvent.Wait();
 }
 
 void OpenALStream::Clear(bool mute)
@@ -149,10 +147,12 @@ void OpenALStream::SoundLoop()
 	memset(realtimeBuffer, 0, OAL_MAX_SAMPLES * 4);
 	for (int i = 0; i < OAL_NUM_BUFFERS; i++)
 	{
+#if !defined(__APPLE__)
 		if (Core::g_CoreStartupParameter.bDPL2Decoder)
-			alBufferData(uiBuffers[i], AL_FORMAT_51CHN32, sampleBuffer, OAL_MAX_SAMPLES * SIZE_FLOAT * SURROUND_CHANNELS * OAL_NUM_BUFFERS, ulFrequency);
+			alBufferData(uiBuffers[i], AL_FORMAT_51CHN32, sampleBuffer, 4 * SIZE_FLOAT * SURROUND_CHANNELS, ulFrequency);
 		else
-			alBufferData(uiBuffers[i], AL_FORMAT_STEREO16, realtimeBuffer, OAL_MAX_SAMPLES * 4, ulFrequency);
+#endif
+			alBufferData(uiBuffers[i], AL_FORMAT_STEREO16, realtimeBuffer, 4 * 2 * 2, ulFrequency);
 	}
 	alSourceQueueBuffers(uiSource, OAL_NUM_BUFFERS, uiBuffers);
 	alSourcePlay(uiSource);
@@ -165,6 +165,7 @@ void OpenALStream::SoundLoop()
 
 	ALint iBuffersFilled = 0;
 	ALint iBuffersProcessed = 0;
+	ALint iState = 0;
 	ALuint uiBufferTemp[OAL_NUM_BUFFERS] = {0};
 
 	soundTouch.setChannels(2);
@@ -232,7 +233,7 @@ void OpenALStream::SoundLoop()
 				if (surround_capable)
 				{
 					// Convert the samples from short to float for the dpl2 decoder
-					float dest[OAL_MAX_SAMPLES * 2 * OAL_NUM_BUFFERS];
+					float dest[OAL_MAX_SAMPLES * 2 * 2 * OAL_NUM_BUFFERS];
 					for (u32 i = 0; i < nSamples; ++i)
 					{
 						dest[i * 2 + 0] = (float)sampleBuffer[i * 2 + 0] / (1<<16);
@@ -247,7 +248,7 @@ void OpenALStream::SoundLoop()
 					if (err == AL_INVALID_ENUM)
 					{
 						// 5.1 is not supported by the host, fallback to stereo
-						WARN_LOG(AUDIO, "Unable set 5.1 surround mode.  Updating OpenAL Soft might fix this issue.");
+						WARN_LOG(AUDIO, "Unable to set 5.1 surround mode.  Updating OpenAL Soft might fix this issue.");
 						surround_capable = false;
 					}
 					else if (err != 0)
@@ -278,13 +279,24 @@ void OpenALStream::SoundLoop()
 						ERROR_LOG(AUDIO, "Error occurred during playback: %08x", err);
 					}
 				}
+
+				alGetSourcei(uiSource, AL_SOURCE_STATE, &iState);
+				if (iState != AL_PLAYING)
+				{
+					// Buffer underrun occurred, resume playback
+					alSourcePlay(uiSource);
+					ALenum err = alGetError();
+					if (err != 0)
+					{
+						ERROR_LOG(AUDIO, "Error occurred resuming playback: %08x", err);
+					}
+				}
 			}
 		}
 		else
 		{
 			soundSyncEvent.Wait();
 		}
-		mainSyncEvent.Set();
 	}
 }
 
diff --git a/Source/Core/DolphinWX/Src/ConfigMain.cpp b/Source/Core/DolphinWX/Src/ConfigMain.cpp
index 9f38c5db69..78fc886c10 100644
--- a/Source/Core/DolphinWX/Src/ConfigMain.cpp
+++ b/Source/Core/DolphinWX/Src/ConfigMain.cpp
@@ -638,6 +638,7 @@ void CConfigMain::CreateGUIControls()
 	{
 		FrequencySelection->Disable();
 		BackendSelection->Disable();
+		DPL2Decoder->Disable();
 	}
 
 	// Create sizer and add items to dialog