Multi-threaded audio streams

Under MULTITHREADED_AUDIO define.

src/audio/oal/stream.cpp

@@ -1,8 +1,6 @@
 #include "common.h"
 
 #ifdef AUDIO_OAL
-#include "stream.h"
-#include "sampman.h"
 
 #if defined _MSC_VER && !defined RE3_NO_AUTOLINK
 #ifdef AUDIO_OAL_USE_SNDFILE
@@ -22,6 +20,28 @@
 #include <opusfile.h>
 #endif
 
+#include <queue>
+#include <utility>
+
+#ifdef MULTITHREADED_AUDIO
+#include <iostream>
+#include <thread>
+#include <mutex>
+#include <condition_variable>
+#include "MusicManager.h"
+#include "stream.h"
+
+std::thread	gAudioThread;
+std::mutex gAudioThreadQueueMutex;
+std::condition_variable gAudioThreadCv;
+bool gAudioThreadTerm = false;
+std::queue<CStream*> gStreamsToProcess; // values are not unique, we will handle that ourself
+#else
+#include "stream.h"
+#endif
+
+#include "sampman.h"
+
 #ifndef _WIN32
 #include "crossplatform.h"
 #endif
@@ -39,6 +59,10 @@ class CSortStereoBuffer
 {
 	uint16* PcmBuf;
 	size_t BufSize;
+//#ifdef MULTITHREADED_AUDIO
+//	std::mutex Mutex;
+//#endif
+
 public:
 	CSortStereoBuffer() : PcmBuf(nil), BufSize(0) {}
 	~CSortStereoBuffer()
@@ -65,6 +89,9 @@ public:
 
 	void SortStereo(void* buf, size_t size)
 	{
+//#ifdef MULTITHREADED_AUDIO
+//		std::lock_guard<std::mutex> lock(Mutex);
+//#endif
 		uint16* InBuf = (uint16*)buf;
 		uint16* OutBuf = GetBuffer(size);
 
@@ -279,6 +306,10 @@ public:
 #undef CLOSE_ON_ERROR
 	}
 
+	void FileOpen()
+	{
+	}
+
 	~CWavFile()
 	{
 		Close();
@@ -289,6 +320,7 @@ public:
 		return m_bIsOpen;
 	}
 
+
 	uint32 GetSampleSize()
 	{
 		return sizeof(uint16);
@@ -405,6 +437,10 @@ public:
 		m_pfSound = sf_open(path, SFM_READ, &m_soundInfo);
 	}
 	
+	void FileOpen()
+	{
+	}
+
 	~CSndFile()
 	{
 		if ( m_pfSound )
@@ -464,8 +500,6 @@ public:
 #endif
 
 #ifdef AUDIO_OAL_USE_MPG123
-// fuzzy seek eliminates stutter when playing ADF but spams errors a lot (nothing breaks though)
-#define MP3_USE_FUZZY_SEEK
 
 class CMP3File : public IDecoder
 {
@@ -473,37 +507,51 @@ class CMP3File : public IDecoder
 	bool m_bOpened;
 	uint32 m_nRate;
 	uint32 m_nChannels;
+	const char* m_pPath;
+	bool m_bFileNotOpenedYet;
 public:
 	CMP3File(const char *path) :
 		m_pMH(nil),
 		m_bOpened(false),
 		m_nRate(0),
-		m_nChannels(0)
+		m_nChannels(0),
+		m_pPath(path),
+		m_bFileNotOpenedYet(false)
 	{
 		m_pMH = mpg123_new(nil, nil);
 		if ( m_pMH )
 		{
-#ifdef MP3_USE_FUZZY_SEEK
+			mpg123_param(m_pMH, MPG123_FLAGS, MPG123_SEEKBUFFER | MPG123_GAPLESS, 0.0);
-			mpg123_param(m_pMH, MPG123_FLAGS, MPG123_FUZZY | MPG123_SEEKBUFFER | MPG123_GAPLESS | MPG123_QUIET, 0.0);
-#endif
-			long rate = 0;
-			int channels = 0;
-			int encoding = 0;
-			
-			m_bOpened = mpg123_open(m_pMH, path) == MPG123_OK
-				&& mpg123_getformat(m_pMH, &rate, &channels, &encoding) == MPG123_OK;
 
-			m_nRate = rate;
+			m_bOpened = true;
-			m_nChannels = channels;
+			m_bFileNotOpenedYet = true;
-			
+			// It's possible to move this to audioFileOpsThread(), but effect isn't noticable + probably not compatible with our current cutscene audio handling
-			if ( IsOpened() )
+#if 1
-			{
+			FileOpen();
-				mpg123_format_none(m_pMH);
+#endif
-				mpg123_format(m_pMH, rate, channels, encoding);
-			}
 		}
 	}
 	
+	void FileOpen()
+	{
+		if(!m_bFileNotOpenedYet) return;
+
+		long rate = 0;
+		int channels = 0;
+		int encoding = 0;
+		m_bOpened = mpg123_open(m_pMH, m_pPath) == MPG123_OK
+		        && mpg123_getformat(m_pMH, &rate, &channels, &encoding) == MPG123_OK;
+
+		m_nRate = rate;
+		m_nChannels = channels;
+
+		if(IsOpened()) {
+			mpg123_format_none(m_pMH);
+			mpg123_format(m_pMH, rate, channels, encoding);
+		}
+		m_bFileNotOpenedYet = false;
+	}
+
 	~CMP3File()
 	{
 		if ( m_pMH )
@@ -526,7 +574,7 @@ public:
 	
 	uint32 GetSampleCount()
 	{
-		if ( !IsOpened() ) return 0;
+		if ( !IsOpened() || m_bFileNotOpenedYet ) return 0;
 		return mpg123_length(m_pMH);
 	}
 	
@@ -542,19 +590,19 @@ public:
 	
 	void Seek(uint32 milliseconds)
 	{
-		if ( !IsOpened() ) return;
+		if ( !IsOpened() || m_bFileNotOpenedYet ) return;
 		mpg123_seek(m_pMH, ms2samples(milliseconds), SEEK_SET);
 	}
 	
 	uint32 Tell()
 	{
-		if ( !IsOpened() ) return 0;
+		if ( !IsOpened() || m_bFileNotOpenedYet ) return 0;
 		return samples2ms(mpg123_tell(m_pMH));
 	}
 	
 	uint32 Decode(void *buffer)
 	{
-		if ( !IsOpened() ) return 0;
+		if ( !IsOpened() || m_bFileNotOpenedYet ) return 0;
 		
 		size_t size;
 		int err = mpg123_read(m_pMH, (unsigned char *)buffer, GetBufferSize(), &size);
@@ -685,6 +733,10 @@ public:
 			m_ppVagBuffers[i] = new uint8[VB_BLOCK_SIZE];
 	}
 
+	void FileOpen()
+	{
+	}
+
 	~CVbFile()
 	{
 		if (m_pFile)
@@ -837,6 +889,10 @@ public:
 			m_bOpened = true;
 		}
 	}
+
+	void FileOpen()
+	{
+	}
 	
 	~COpusFile()
 	{
@@ -902,11 +958,183 @@ public:
 };
 #endif
 
+
+// For multi-thread: Someone always acquire stream's mutex before entering here
+void
+CStream::BuffersShouldBeFilled()
+{
+#ifdef MULTITHREADED_AUDIO
+	if (MusicManager.m_nMusicMode != MUSICMODE_CUTSCENE) {
+		std::queue<std::pair<ALuint, ALuint>> tempQueue;
+		for(int i = 0; i < NUM_STREAMBUFFERS / 2; i++) {
+			tempQueue.push(std::pair<ALuint, ALuint>(m_alBuffers[i * 2], m_alBuffers[i * 2 + 1]));
+		}
+		m_fillBuffers.swap(tempQueue);
+
+		FlagAsToBeProcessed();
+
+		m_bActive = true; // to allow Update() to queue the filled buffers & play
+		return;
+	}
+	std::queue<std::pair<ALuint, ALuint>>().swap(m_fillBuffers);
+#endif
+	if ( FillBuffers() != 0 )
+	{
+		SetPlay(true);
+	}
+}
+
+// returns whether it's queued (not on multi-thread)
+bool
+CStream::BufferShouldBeFilledAndQueued(std::pair<ALuint, ALuint>* bufs)
+{
+#ifdef MULTITHREADED_AUDIO
+	if (MusicManager.m_nMusicMode != MUSICMODE_CUTSCENE)
+		m_fillBuffers.push(*bufs);
+	else
+#endif
+	{
+		ALuint alBuffers[2] = {(*bufs).first, (*bufs).second}; // left - right
+		if (FillBuffer(alBuffers)) {
+			alSourceQueueBuffers(m_pAlSources[0], 1, &alBuffers[0]);
+			alSourceQueueBuffers(m_pAlSources[1], 1, &alBuffers[1]);
+			return true;
+		}
+	}
+	return false;
+}
+
+#ifdef MULTITHREADED_AUDIO
+void
+CStream::FlagAsToBeProcessed(bool close)
+{
+	if (!close && MusicManager.m_nMusicMode == MUSICMODE_CUTSCENE)
+		return;
+
+	gAudioThreadQueueMutex.lock();
+	gStreamsToProcess.push(this);
+	gAudioThreadQueueMutex.unlock();
+
+	gAudioThreadCv.notify_one();
+}
+
+extern CStream *aStream[];
+void audioFileOpsThread()
+{
+	std::queue<CStream*> m_streamsToDelete;
+
+	do
+	{
+		CStream *stream;
+		{
+			// Just a semaphore
+			std::unique_lock<std::mutex> queueMutex(gAudioThreadQueueMutex);
+			gAudioThreadCv.wait(queueMutex, [m_streamsToDelete] { return gStreamsToProcess.size() > 0 || m_streamsToDelete.size() > 0 || gAudioThreadTerm; });
+			if (gAudioThreadTerm)
+				return;
+
+			if (!gStreamsToProcess.empty()) {
+				stream = gStreamsToProcess.front();
+				gStreamsToProcess.pop();
+			} else {
+				// End of streams. Perform deleting streams
+				while(!m_streamsToDelete.empty()) {
+					CStream *stream = m_streamsToDelete.front();
+					m_streamsToDelete.pop();
+					if (stream->m_pSoundFile) {
+						delete stream->m_pSoundFile;
+						stream->m_pSoundFile = nil;
+					}
+	
+					if (stream->m_pBuffer) {
+						free(stream->m_pBuffer);
+						stream->m_pBuffer = nil;
+					}
+					delete stream;
+				}
+				continue;
+			}
+		}
+
+		std::unique_lock<std::mutex> lock(stream->m_mutex);
+
+		std::pair<ALuint, ALuint> buffers, *lastBufAddr;
+		bool insertBufsAfterCheck = false;
+
+		do {
+			if (stream->m_nDeleteMe == 1) {
+				m_streamsToDelete.push(stream);
+				stream->m_nDeleteMe = 2;
+				break;
+			} else if (stream->m_nDeleteMe == 2) {
+				break;
+			}
+
+			if (!stream->IsOpened())
+				break;
+
+			if (stream->m_bReset)
+				break;
+
+			// We gave up this idea for now
+			/*
+			stream->m_pSoundFile->FileOpen();
+
+			// Deffered allocation, do it now
+			if (stream->m_pBuffer == nil) {
+				stream->m_pBuffer = malloc(stream->m_pSoundFile->GetBufferSize());
+				ASSERT(stream->m_pBuffer != nil);
+			}
+			*/
+
+			if (stream->m_bDoSeek) {
+				stream->m_bDoSeek = false;
+				int pos = stream->m_SeekPos;
+				lock.unlock();
+				stream->m_pSoundFile->Seek(pos);
+				lock.lock();
+
+				continue; // let's do the checks again, make sure we didn't miss anything while Seeking
+			}
+
+			if (insertBufsAfterCheck) {
+				stream->m_queueBuffers.push(buffers);
+				insertBufsAfterCheck = false;
+			}
+
+			if (!stream->m_fillBuffers.empty()) {
+				lastBufAddr = &stream->m_fillBuffers.front();
+				buffers = *lastBufAddr;
+				lock.unlock();
+
+				ALuint alBuffers[2] = {buffers.first, buffers.second}; // left - right
+				bool filled = stream->FillBuffer(alBuffers);
+				
+				lock.lock();
+			
+				// Make sure queue isn't touched after we released mutex
+				if (!stream->m_fillBuffers.empty() && lastBufAddr == &stream->m_fillBuffers.front()) {
+					stream->m_fillBuffers.pop();
+					if (filled)
+						insertBufsAfterCheck = true; // Also make sure stream's properties aren't changed. So make one more pass, and push it to m_queueBuffers only if it pass checks again.
+				}
+			} else
+				break;
+
+		} while (true);
+
+	} while(true);
+}
+#endif
+
 void CStream::Initialise()
 {
 #ifdef AUDIO_OAL_USE_MPG123
 	mpg123_init();
 #endif
+#ifdef MULTITHREADED_AUDIO
+	gAudioThread = std::thread(audioFileOpsThread);
+#endif
 }
 
 void CStream::Terminate()
@@ -914,6 +1142,14 @@ void CStream::Terminate()
 #ifdef AUDIO_OAL_USE_MPG123
 	mpg123_exit();
 #endif
+#ifdef MULTITHREADED_AUDIO
+	gAudioThreadQueueMutex.lock();
+	gAudioThreadTerm = true;
+	gAudioThreadQueueMutex.unlock();
+
+	gAudioThreadCv.notify_one();
+	gAudioThread.join();
+#endif
 }
 
 CStream::CStream(char *filename, ALuint *sources, ALuint (&buffers)[NUM_STREAMBUFFERS], uint32 overrideSampleRate) :
@@ -922,6 +1158,11 @@ CStream::CStream(char *filename, ALuint *sources, ALuint (&buffers)[NUM_STREAMBU
 	m_pBuffer(nil),
 	m_bPaused(false),
 	m_bActive(false),
+#ifdef MULTITHREADED_AUDIO
+	m_nDeleteMe(false),
+	m_bDoSeek(false),
+	m_SeekPos(0),
+#endif
 	m_pSoundFile(nil),
 	m_bReset(false),
 	m_nVolume(0),
@@ -966,42 +1207,57 @@ CStream::CStream(char *filename, ALuint *sources, ALuint (&buffers)[NUM_STREAMBU
 
 	if ( IsOpened() )
 	{
-		m_pBuffer            = malloc(m_pSoundFile->GetBufferSize());
+		uint32 bufSize = m_pSoundFile->GetBufferSize();
-		ASSERT(m_pBuffer!=nil);
+		if(bufSize != 0) { // Otherwise it's deferred
-		
+			m_pBuffer = malloc(bufSize);
-		DEV("AvgSamplesPerSec: %d\n", m_pSoundFile->GetAvgSamplesPerSec());
+			ASSERT(m_pBuffer != nil);
-		DEV("SampleCount: %d\n",      m_pSoundFile->GetSampleCount());
+
-		DEV("SampleRate: %d\n",       m_pSoundFile->GetSampleRate());
+			DEV("AvgSamplesPerSec: %d\n", m_pSoundFile->GetAvgSamplesPerSec());
-		DEV("Channels: %d\n",         m_pSoundFile->GetChannels());
+			DEV("SampleCount: %d\n",      m_pSoundFile->GetSampleCount());
-		DEV("Buffer Samples: %d\n",   m_pSoundFile->GetBufferSamples());
+			DEV("SampleRate: %d\n",       m_pSoundFile->GetSampleRate());
-		DEV("Buffer sec: %f\n",       (float(m_pSoundFile->GetBufferSamples()) / float(m_pSoundFile->GetChannels())/ float(m_pSoundFile->GetSampleRate())));
+			DEV("Channels: %d\n",         m_pSoundFile->GetChannels());
-		DEV("Length MS: %02d:%02d\n", (m_pSoundFile->GetLength() / 1000) / 60, (m_pSoundFile->GetLength() / 1000) % 60);
+			DEV("Buffer Samples: %d\n",   m_pSoundFile->GetBufferSamples());
-		
+			DEV("Buffer sec: %f\n",       (float(m_pSoundFile->GetBufferSamples()) / float(m_pSoundFile->GetChannels())/ float(m_pSoundFile->GetSampleRate())));
+			DEV("Length MS: %02d:%02d\n", (m_pSoundFile->GetLength() / 1000) / 60, (m_pSoundFile->GetLength() / 1000) % 60);
+		}
 		return;
 	}
 }
 
 CStream::~CStream()
 {
-	Delete();
+	assert(!IsOpened());
 }
 
-void CStream::Delete()
+void CStream::Close()
 {
+#ifdef MULTITHREADED_AUDIO
+	{
+		std::lock_guard<std::mutex> lock(m_mutex);
+
+		Stop();
+		ClearBuffers();
+		m_nDeleteMe = true;
+		// clearing buffer queues are not needed. after m_nDeleteMe set, this stream is ded 
+	}
+
+	FlagAsToBeProcessed(true);
+#else
 	Stop();
 	ClearBuffers();
-	
+
 	if ( m_pSoundFile )
 	{
 		delete m_pSoundFile;
 		m_pSoundFile = nil;
 	}
-	
+
 	if ( m_pBuffer )
 	{
 		free(m_pBuffer);
 		m_pBuffer = nil;
 	}
+#endif
 }
 
 bool CStream::HasSource()
@@ -1025,6 +1281,14 @@ bool CStream::IsPlaying()
 		alGetSourcei(m_pAlSources[1], AL_SOURCE_STATE, &sourceState[1]);
 		if (sourceState[0] == AL_PLAYING || sourceState[1] == AL_PLAYING)
 			return true;
+
+#ifdef MULTITHREADED_AUDIO
+		std::lock_guard<std::mutex> lock(m_mutex);
+
+		// Streams are designed in such a way that m_fillBuffers and m_queueBuffers will be *always* filled if audio is playing, and mutex is acquired
+		if (!m_fillBuffers.empty() || !m_queueBuffers.emptyNts())
+			return true;
+#endif
 	}
 	
 	return false;
@@ -1099,8 +1363,24 @@ void CStream::SetPan(uint8 nPan)
 void CStream::SetPosMS(uint32 nPos)
 {
 	if ( !IsOpened() ) return;
-	m_pSoundFile->Seek(nPos);
+	
+#ifdef MULTITHREADED_AUDIO
+	std::lock_guard<std::mutex> lock(m_mutex);
+
+	std::queue<std::pair<ALuint, ALuint>>().swap(m_fillBuffers);
+	tsQueue<std::pair<ALuint, ALuint>>().swapNts(m_queueBuffers); // TSness not required, second thread always access it when stream mutex acquired
+
+	if (MusicManager.m_nMusicMode != MUSICMODE_CUTSCENE) {
+		m_bDoSeek = true;
+		m_SeekPos = nPos;
+	} else
+#endif	
+	{
+		m_pSoundFile->Seek(nPos);
+	}	
 	ClearBuffers();
+	
+	// adding to gStreamsToProcess not needed, someone always calls Start() / BuffersShouldBeFilled() after SetPosMS
 }
 
 uint32 CStream::GetPosMS()
@@ -1108,10 +1388,16 @@ uint32 CStream::GetPosMS()
 	if ( !HasSource() ) return 0;
 	if ( !IsOpened() ) return 0;
 	
+	// Deferred init causes division by zero
+	if (m_pSoundFile->GetChannels() == 0)
+		return 0;
+
 	ALint offset;
 	//alGetSourcei(m_alSource, AL_SAMPLE_OFFSET, &offset);
 	alGetSourcei(m_pAlSources[0], AL_BYTE_OFFSET, &offset);
 
+	//std::lock_guard<std::mutex> lock(m_mutex);
+
 	return m_pSoundFile->Tell()
 		- m_pSoundFile->samples2ms(m_pSoundFile->GetBufferSamples() * (NUM_STREAMBUFFERS/2-1)) / m_pSoundFile->GetChannels()
 		+ m_pSoundFile->samples2ms(offset/m_pSoundFile->GetSampleSize()) / m_pSoundFile->GetChannels();
@@ -1125,6 +1411,7 @@ uint32 CStream::GetLengthMS()
 
 bool CStream::FillBuffer(ALuint *alBuffer)
 {
+#ifndef MULTITHREADED_AUDIO
 	if ( !HasSource() )
 		return false;
 	if ( !IsOpened() )
@@ -1133,7 +1420,8 @@ bool CStream::FillBuffer(ALuint *alBuffer)
 		return false;
 	if ( !(alBuffer[1] != AL_NONE && alIsBuffer(alBuffer[1])) )
 		return false;
-	
+#endif
+
 	uint32 size = m_pSoundFile->Decode(m_pBuffer);
 	if( size == 0 )
 		return false;
@@ -1149,6 +1437,26 @@ bool CStream::FillBuffer(ALuint *alBuffer)
 	return true;
 }
 
+#ifdef MULTITHREADED_AUDIO
+bool CStream::QueueBuffers()
+{
+	bool buffersQueued = false;
+	std::pair<ALuint, ALuint> buffers;
+	while (m_queueBuffers.peekPop(&buffers)) // beware: m_queueBuffers is tsQueue
+	{
+		ALuint leftBuf = buffers.first;
+		ALuint rightBuf = buffers.second;
+
+		alSourceQueueBuffers(m_pAlSources[0], 1, &leftBuf);
+		alSourceQueueBuffers(m_pAlSources[1], 1, &rightBuf);
+
+		buffersQueued = true;
+	}
+	return buffersQueued;	
+}
+#endif
+
+// Only used in single-threaded audio or cutscene audio
 int32 CStream::FillBuffers()
 {
 	int32 i = 0;
@@ -1178,17 +1486,33 @@ void CStream::ClearBuffers()
 		alSourceUnqueueBuffers(m_pAlSources[1], 1, &value);
 }
 
-bool CStream::Setup(bool imSureQueueIsEmpty)
+bool CStream::Setup(bool imSureQueueIsEmpty, bool lock)
 {
 	if ( IsOpened() )
 	{
-		alSourcei(m_pAlSources[0], AL_LOOPING, AL_FALSE);
+#ifdef MULTITHREADED_AUDIO
-		alSourcei(m_pAlSources[1], AL_LOOPING, AL_FALSE);
+		if (lock)
+			m_mutex.lock();
+#endif
+
 		if (!imSureQueueIsEmpty) {
-			SetPlay(false);
+			Stop();
 			ClearBuffers();
 		}
+#ifdef MULTITHREADED_AUDIO
+		if (MusicManager.m_nMusicMode == MUSICMODE_CUTSCENE) {
+			m_pSoundFile->Seek(0);
+		} else {
+			m_bDoSeek = true;
+			m_SeekPos = 0;
+		}
+
+		if (lock)
+			m_mutex.unlock();
+#else
 		m_pSoundFile->Seek(0);
+#endif
+
 		//SetPosition(0.0f, 0.0f, 0.0f);
 		SetPitch(1.0f);
 		//SetPan(m_nPan);
@@ -1241,8 +1565,12 @@ void CStream::SetPlay(bool state)
 void CStream::Start()
 {
 	if ( !HasSource() ) return;
-	if ( FillBuffers() != 0 )
+	
-		SetPlay(true);
+#ifdef MULTITHREADED_AUDIO
+	std::lock_guard<std::mutex> lock(m_mutex);
+	tsQueue<std::pair<ALuint, ALuint>>().swapNts(m_queueBuffers); // TSness not required, second thread always access it when stream mutex acquired
+#endif
+	BuffersShouldBeFilled();
 }
 
 void CStream::Stop()
@@ -1264,9 +1592,23 @@ void CStream::Update()
 	
 	if ( !m_bPaused )
 	{
-		ALint totalBuffers[2] = { 0, 0 };
-		ALint buffersProcessed[2] = { 0, 0 };
 		
+		bool buffersQueuedAndStarted = false;
+		bool buffersQueuedButNotStarted = false;
+#ifdef MULTITHREADED_AUDIO
+		// Put it in here because we need totalBuffers after queueing to decide when to loop audio
+		if (m_bActive)
+		{
+			buffersQueuedAndStarted = QueueBuffers();
+			if(buffersQueuedAndStarted) {
+				SetPlay(true);
+			}
+		}
+#endif
+
+		ALint totalBuffers[2] = {0, 0};
+		ALint buffersProcessed[2] = {0, 0};
+
 		// Relying a lot on left buffer states in here
 
 		do
@@ -1278,44 +1620,66 @@ void CStream::Update()
 			alGetSourcei(m_pAlSources[1], AL_BUFFERS_QUEUED, &totalBuffers[1]);
 			alGetSourcei(m_pAlSources[1], AL_BUFFERS_PROCESSED, &buffersProcessed[1]);
 		} while (buffersProcessed[0] != buffersProcessed[1]);
-		
+
 		assert(buffersProcessed[0] == buffersProcessed[1]);
 
 		// Correcting OpenAL concepts here:
 		// AL_BUFFERS_QUEUED = Number of *all* buffers in queue, including processed, processing and pending
 		// AL_BUFFERS_PROCESSED = Index of the buffer being processing right now. Buffers coming after that(have greater index) are pending buffers.
 		// which means: totalBuffers[0] - buffersProcessed[0] = pending buffers
-
+		
-		bool buffersRefilled = false;
-
 		// We should wait queue to be cleared to loop track, because position calculation relies on queue.
 		if (m_nLoopCount != 1 && m_bActive && totalBuffers[0] == 0)
 		{
-			Setup(true);
+#ifdef MULTITHREADED_AUDIO
-			buffersRefilled = FillBuffers() != 0;
+			std::lock_guard<std::mutex> lock(m_mutex);
-			if (m_nLoopCount != 0)
+
-				m_nLoopCount--;
+			if (m_fillBuffers.empty() && m_queueBuffers.emptyNts()) // we already acquired stream mutex, which is enough for second thread. thus Nts variant
+#endif
+			{
+				Setup(true, false);
+				BuffersShouldBeFilled(); // will also call SetPlay(true)
+				if (m_nLoopCount != 0)
+					m_nLoopCount--;
+			}
 		}
 		else
 		{
-			while( buffersProcessed[0]-- )
+			static std::queue<std::pair<ALuint, ALuint>> tempFillBuffer;
+
+			while ( buffersProcessed[0]-- )
 			{
 				ALuint buffer[2];
 				
 				alSourceUnqueueBuffers(m_pAlSources[0], 1, &buffer[0]);
 				alSourceUnqueueBuffers(m_pAlSources[1], 1, &buffer[1]);
-				
+
-				if (m_bActive && FillBuffer(buffer))
+				if (m_bActive)
 				{
-					buffersRefilled = true;
+					tempFillBuffer.push(std::pair<ALuint, ALuint>(buffer[0], buffer[1]));
-					alSourceQueueBuffers(m_pAlSources[0], 1, &buffer[0]);
-					alSourceQueueBuffers(m_pAlSources[1], 1, &buffer[1]);
 				}
 			}
+
+			if (m_bActive && buffersProcessed[1])
+			{
+#ifdef MULTITHREADED_AUDIO
+				m_mutex.lock();
+#endif
+				while (!tempFillBuffer.empty()) {
+					auto elem = tempFillBuffer.front();
+					tempFillBuffer.pop();
+					buffersQueuedButNotStarted = BufferShouldBeFilledAndQueued(&elem);
+				}
+#ifdef MULTITHREADED_AUDIO
+				m_mutex.unlock();
+				FlagAsToBeProcessed();
+#endif
+
+			}
 		}
 
-		// Two reasons: 1-Source may be starved to audio and stopped itself, 2- We're already waiting it to starve and die for looping track!
+		// Source may be starved to audio and stopped itself
-		if (m_bActive && (buffersRefilled || (totalBuffers[1] - buffersProcessed[1] != 0)))
+		if (m_bActive && !buffersQueuedAndStarted && (buffersQueuedButNotStarted || (totalBuffers[1] - buffersProcessed[1] != 0)))
 			SetPlay(true);
 	}
 }
@@ -1324,28 +1688,45 @@ void CStream::ProviderInit()
 {
 	if ( m_bReset )
 	{
-		if ( Setup(true) )
+		if ( Setup(true, false) ) // lock not needed, thread can't process streams with m_bReset set
 		{
 			SetPan(m_nPan);
 			SetVolume(m_nVolume);
 			SetLoopCount(m_nLoopCount);
 			SetPosMS(m_nPosBeforeReset);
-			if (m_bActive)
+#ifdef MULTITHREADED_AUDIO
-				FillBuffers();
+			std::unique_lock<std::mutex> lock(m_mutex);
-			SetPlay(m_bActive);
+#endif
-			if ( m_bPaused )
+			if(m_bActive)
+				BuffersShouldBeFilled();
+
+			if (m_bPaused)
 				Pause();
+
+			m_bReset = false;
+
+		} else {
+#ifdef MULTITHREADED_AUDIO
+			std::unique_lock<std::mutex> lock(m_mutex);
+#endif
+			m_bReset = false;
 		}
-	
-		m_bReset = false;
 	}
 }
 
 void CStream::ProviderTerm()
 {
+#ifdef MULTITHREADED_AUDIO
+	std::lock_guard<std::mutex> lock(m_mutex);
+
+	// unlike Close() we will reuse this stream, so clearing queues are important.
+	std::queue<std::pair<ALuint, ALuint>>().swap(m_fillBuffers);
+	tsQueue<std::pair<ALuint, ALuint>>().swapNts(m_queueBuffers); // stream mutex is already acquired, thus Nts variant
+#endif
 	m_bReset = true;
 	m_nPosBeforeReset = GetPosMS();
-	
+
+	Stop();
 	ClearBuffers();
 }
 	

src/audio/oal/stream.h

@@ -11,6 +11,7 @@ public:
 	virtual ~IDecoder() { }
 	
 	virtual bool   IsOpened() = 0;
+	virtual void   FileOpen() = 0;
 	
 	virtual uint32 GetSampleSize() = 0;
 	virtual uint32 GetSampleCount() = 0;
@@ -48,12 +49,70 @@ public:
 	
 	uint32 GetLength()
 	{
+		FileOpen(); // abort deferred init, we need length now - game has to cache audio file sizes
 		return float(GetSampleCount()) * 1000.0f / float(GetSampleRate());
 	}
 	
 	virtual uint32 Decode(void *buffer) = 0;
 };
+#ifdef MULTITHREADED_AUDIO
+template <typename T> class tsQueue
+{
+public:
+	tsQueue() : count(0) { }
+	
+	void push(const T &value)
+	{
+		std::lock_guard<std::mutex> lock(m_mutex);
+		m_queue.push(value);
+		count++;
+	}
 
+    bool peekPop(T *retVal)
+    {
+        std::lock_guard<std::mutex> lock(m_mutex);
+        if (count == 0)
+            return false;
+
+        *retVal = m_queue.front();
+        m_queue.pop();
+        count--;
+        return true;
+    }
+
+	void swapNts(tsQueue<T> &replaceWith)
+	{
+		m_queue.swap(replaceWith.m_queue);
+		replaceWith.count = count;
+	}
+
+	/*
+	void swapTs(tsQueue<T> &replaceWith)
+	{
+		std::lock_guard<std::mutex> lock(m_mutex);
+		std::lock_guard<std::mutex> lock2(replaceWith.m_mutex);
+		swapNts(replaceWith);
+	}
+	*/
+
+	bool emptyNts()
+	{
+		return count == 0;
+	}
+
+	/*
+	bool emptyTs()
+	{
+		std::lock_guard<std::mutex> lock(m_mutex);
+		return emptyNts();
+	}
+	*/
+	
+	std::queue<T> m_queue;
+	int count;
+	mutable std::mutex m_mutex;
+};
+#endif
 class CStream
 {
 	char     m_aFilename[128];
@@ -63,6 +122,16 @@ class CStream
 	bool     m_bPaused;
 	bool     m_bActive;
 	
+public:
+#ifdef MULTITHREADED_AUDIO
+	std::mutex	m_mutex;
+	std::queue<std::pair<ALuint, ALuint>> m_fillBuffers; // left and right buffer
+	tsQueue<std::pair<ALuint, ALuint>> m_queueBuffers;
+	bool     m_bDoSeek;
+	uint32   m_SeekPos;
+	uint8	 m_nDeleteMe; // 1: add to delete list 2: already on delete list
+#endif
+
 	void    *m_pBuffer;
 	
 	bool     m_bReset;
@@ -72,7 +141,14 @@ class CStream
 	int32   m_nLoopCount;
 	
 	IDecoder *m_pSoundFile;
-	
+
+	void BuffersShouldBeFilled(); // all
+	bool BufferShouldBeFilledAndQueued(std::pair<ALuint, ALuint>*); // two (left-right)
+#ifdef MULTITHREADED_AUDIO
+	void FlagAsToBeProcessed(bool close = false);
+	bool QueueBuffers();
+#endif
+
 	bool HasSource();
 	void SetPosition(int i, float x, float y, float z);
 	void SetPitch(float pitch);
@@ -81,15 +157,15 @@ class CStream
 	void   SetPlay(bool state);
 	
 	bool   FillBuffer(ALuint *alBuffer);
-	int32  FillBuffers();
+	int32	FillBuffers();
 	void   ClearBuffers();
-public:
+//public:
 	static void Initialise();
 	static void Terminate();
 	
 	CStream(char *filename, ALuint *sources, ALuint (&buffers)[NUM_STREAMBUFFERS], uint32 overrideSampleRate = 32000);
 	~CStream();
-	void   Delete();
+	void   Close();
 	
 	bool   IsOpened();
 	bool   IsPlaying();
@@ -100,12 +176,11 @@ public:
 	uint32 GetPosMS();
 	uint32 GetLengthMS();
 	
-	bool Setup(bool imSureQueueIsEmpty = false);
+	bool Setup(bool imSureQueueIsEmpty = false, bool lock = true);
 	void Start();
 	void Stop();
 	void Update(void);
 	void SetLoopCount(int32);
-
 	
 	void ProviderInit();
 	void ProviderTerm();

src/audio/sampman_oal.cpp

@@ -34,6 +34,12 @@
 #include "oal/oal_utils.h"
 #include "oal/aldlist.h"
 #include "oal/channel.h"
+
+#include <utility>
+#ifdef MULTITHREADED_AUDIO
+#include <mutex>
+#include <queue>
+#endif
 #include "oal/stream.h"
 
 #include "AudioManager.h"
@@ -520,7 +526,7 @@ _FindMP3s(void)
 				if (aStream[0] && aStream[0]->IsOpened())
 				{
 					total_ms = aStream[0]->GetLengthMS();
-					delete aStream[0];
+					aStream[0]->Close();
 					aStream[0] = NULL;
 
 					OutputDebugString(fd.cFileName);
@@ -578,7 +584,7 @@ _FindMP3s(void)
 				if (aStream[0] && aStream[0]->IsOpened())
 				{
 					total_ms = aStream[0]->GetLengthMS();
-					delete aStream[0];
+					aStream[0]->Close();
 					aStream[0] = NULL;
 
 					pList->pNext = new tMP3Entry;
@@ -732,6 +738,7 @@ cSampleManager::Initialise(void)
 		return TRUE;
 
 	EFXInit();
+
 	CStream::Initialise();
 
 	{
@@ -890,7 +897,7 @@ cSampleManager::Initialise(void)
 
 			if(aStream[0] && aStream[0]->IsOpened()) {
 				uint32 tatalms = aStream[0]->GetLengthMS();
-				delete aStream[0];
+				aStream[0]->Close();
 				aStream[0] = NULL;
 
 				nStreamLength[i] = tatalms;
@@ -939,7 +946,7 @@ cSampleManager::Initialise(void)
 			nStreamPan[i]    = 63;
 		}
 	}
-	
+
 	{
 		_bSampmanInitialised = TRUE;
 		
@@ -1025,7 +1032,7 @@ cSampleManager::Terminate(void)
 		CStream *stream = aStream[i];
 		if (stream)
 		{
-			delete stream;
+			stream->Close();
 			aStream[i] = NULL;
 		}
 	}
@@ -1607,7 +1614,7 @@ cSampleManager::PreloadStreamedFile(uint8 nFile, uint8 nStream)
 	{
 		if ( aStream[nStream] )
 		{
-			delete aStream[nStream];
+			aStream[nStream]->Close();
 			aStream[nStream] = NULL;
 		}
 		
@@ -1619,7 +1626,7 @@ cSampleManager::PreloadStreamedFile(uint8 nFile, uint8 nStream)
 		aStream[nStream] = stream;
 		if ( !stream->Setup() )
 		{
-			delete stream;
+			stream->Close();
 			aStream[nStream] = NULL;
 		}
 	}
@@ -1666,7 +1673,7 @@ cSampleManager::StartStreamedFile(uint8 nFile, uint32 nPos, uint8 nStream)
 
 	if ( aStream[nStream] )
 	{
-		delete aStream[nStream];
+		aStream[nStream]->Close();
 		aStream[nStream] = NULL;
 	}
 	if ( nFile == STREAMED_SOUND_RADIO_MP3_PLAYER )
@@ -1697,7 +1704,7 @@ cSampleManager::StartStreamedFile(uint8 nFile, uint32 nPos, uint8 nStream)
 
 						return TRUE;
 					} else {
-						delete stream;
+						stream->Close();
 						aStream[nStream] = NULL;
 					}
 					return FALSE;
@@ -1721,7 +1728,7 @@ cSampleManager::StartStreamedFile(uint8 nFile, uint32 nPos, uint8 nStream)
 						_bIsMp3Active = TRUE;
 						return TRUE;
 					} else {
-						delete aStream[nStream];
+						aStream[nStream]->Close();
 						aStream[nStream] = NULL;
 					}
 					// fall through, start playing from another song
@@ -1753,7 +1760,7 @@ cSampleManager::StartStreamedFile(uint8 nFile, uint32 nPos, uint8 nStream)
 
 							return TRUE;
 						} else {
-							delete stream;
+							stream->Close();
 							aStream[nStream] = NULL;
 						}
 						return FALSE;
@@ -1775,7 +1782,7 @@ cSampleManager::StartStreamedFile(uint8 nFile, uint32 nPos, uint8 nStream)
 #endif
 					return TRUE;
 				} else {
-					delete aStream[nStream];
+					aStream[nStream]->Close();
 					aStream[nStream] = NULL;
 				}
 
@@ -1800,7 +1807,7 @@ cSampleManager::StartStreamedFile(uint8 nFile, uint32 nPos, uint8 nStream)
 		
 		return TRUE;
 	} else {
-		delete stream;
+		stream->Close();
 		aStream[nStream] = NULL;
 	}
 	return FALSE;
@@ -1815,7 +1822,7 @@ cSampleManager::StopStreamedFile(uint8 nStream)
 	
 	if ( stream )
 	{
-		delete stream;
+		stream->Close();
 		aStream[nStream] = NULL;
 
 		if ( nStream == 0 )

src/core/config.h

@@ -399,6 +399,7 @@ enum Config {
 //#define PS2_AUDIO_PATHS // changes audio paths for cutscenes and radio to PS2 paths (needs vbdec on MSS builds)
 //#define AUDIO_OAL_USE_SNDFILE // use libsndfile to decode WAVs instead of our internal decoder
 #define AUDIO_OAL_USE_MPG123 // use mpg123 to support mp3 files
+#define MULTITHREADED_AUDIO
 #define PAUSE_RADIO_IN_FRONTEND // pause radio when game is paused
 
 #ifdef AUDIO_OPUS