dolphin/Source/Core/AudioCommon/Src/CoreAudioSoundStream.cpp

// Copyright (C) 2003 Dolphin Project.

// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU General Public License as published by
// the Free Software Foundation, version 2.0.

// This program is distributed in the hope that it will be useful,
// but WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License 2.0 for more details.

// A copy of the GPL 2.0 should have been included with the program.
// If not, see http://www.gnu.org/licenses/

// Official SVN repository and contact information can be found at
// http://code.google.com/p/dolphin-emu/

#include "CoreAudioSoundStream.h"

volatile unsigned int numBytesToRender;				/* XXX */

typedef struct internal
{
	AudioUnit audioUnit;
	short realtimeBuffer[1024];				/* XXX */
};

OSStatus callback(void *inRefCon, AudioUnitRenderActionFlags *ioActionFlags,
			const AudioTimeStamp *inTimeStamp, UInt32 inBusNumber,
			UInt32 inNumberFrames, AudioBufferList *ioData)
{
	internal *soundStruct = (internal *)inRefCon;

	for (int i=0; i < (int)ioData->mNumberBuffers; i++)
	{
		memcpy(ioData->mBuffers[i].mData, &soundStruct->realtimeBuffer,
			ioData->mBuffers[i].mDataByteSize);
	}

	numBytesToRender = ioData->mBuffers[0].mDataByteSize;	/* XXX */
	return 0;
}

void CoreAudioSound::SoundLoop()
{
	CoreAudioInit();
}

CoreAudioSound::CoreAudioSound(CMixer *mixer) : SoundStream(mixer)
{
}

CoreAudioSound::~CoreAudioSound()
{
}

bool CoreAudioSound::CoreAudioInit()
{
	ComponentDescription desc;
	OSStatus err;
	UInt32 enableIO;
	AURenderCallbackStruct callback_struct;
	AudioStreamBasicDescription format;
	UInt32 numSamplesPerSlice;
	UInt32 numSamplesPerSliceSize = sizeof numSamplesPerSlice;

	internal *soundStruct = (internal *)malloc(sizeof(internal));
	memset(soundStruct->realtimeBuffer, 0,
		sizeof soundStruct->realtimeBuffer);

	desc.componentType = kAudioUnitType_Output;
	desc.componentSubType = kAudioUnitSubType_HALOutput;
	desc.componentFlags = 0;
	desc.componentFlagsMask = 0;
	desc.componentManufacturer = kAudioUnitManufacturer_Apple;

	Component component = FindNextComponent(NULL, &desc);
	if (component == NULL)
		printf("error finding audio component\n");

	err = OpenAComponent(component, &soundStruct->audioUnit);
	if (err)
		printf("error opening audio component\n");

	//enable output device
	enableIO = 1;
	AudioUnitSetProperty(soundStruct->audioUnit,
				kAudioOutputUnitProperty_EnableIO,
				kAudioUnitScope_Output, 0, &enableIO,
				sizeof enableIO);

	//set audio format
	FillOutASBDForLPCM(format, m_mixer->GetSampleRate(),
				2, 16, 16, false, false, false);
	err = AudioUnitSetProperty(soundStruct->audioUnit,
				kAudioUnitProperty_StreamFormat,
				kAudioUnitScope_Input, 0, &format,
				sizeof(AudioStreamBasicDescription));
	if (err)
		printf("error setting audio format\n");

	callback_struct.inputProc = callback;
	callback_struct.inputProcRefCon = soundStruct;
	err = AudioUnitSetProperty(soundStruct->audioUnit,
				kAudioUnitProperty_SetRenderCallback,
				kAudioUnitScope_Input, 0, &callback_struct,
				sizeof callback_struct);
	if (err)
		printf("error setting audio callback\n");

	err = AudioUnitGetProperty(soundStruct->audioUnit,
				kAudioUnitProperty_MaximumFramesPerSlice,
				kAudioUnitScope_Global, 0,
				&numSamplesPerSlice, &numSamplesPerSliceSize);
	if (err)
		printf("error getting audio buffer size\n");

	numBytesToRender = numSamplesPerSlice * 4;

	err = AudioUnitInitialize(soundStruct->audioUnit);
	if (err)
		printf("error initializing audiounit\n");

	err = AudioOutputUnitStart(soundStruct->audioUnit);
	if (err)
		printf("error starting audiounit\n");

	do
	{
		soundCriticalSection.Enter();
		m_mixer->Mix(soundStruct->realtimeBuffer, numBytesToRender);
		soundCriticalSection.Leave();
		soundSyncEvent.Wait();
	} while(!threadData);

	err = AudioOutputUnitStop(soundStruct->audioUnit);
	if (err)
		printf("error stopping audiounit\n");

	err = AudioUnitUninitialize(soundStruct->audioUnit);
	if (err)
		printf("error uninitializing audiounit\n");

	err = CloseComponent(soundStruct->audioUnit);
	if (err)
		printf("error while closing audio component\n");

	free(soundStruct);
	return true;
}

void *coreAudioThread(void *args)
{

	((CoreAudioSound *)args)->SoundLoop();
	return NULL;
}

bool CoreAudioSound::Start()
{
	soundSyncEvent.Init();
	thread = new Common::Thread(coreAudioThread, (void *)this);
	return true;
}

void CoreAudioSound::Stop()
{
	threadData = 1;
	soundSyncEvent.Set();
	delete thread;
	thread = NULL;

	return;
}

void CoreAudioSound::Update()
{
	soundSyncEvent.Set();
}