livetrax/libs/appleutility/CoreAudio/PublicUtility/CAAudioUnit.cpp

/*
     File: CAAudioUnit.cpp
 Abstract: CAAudioUnit.h
  Version: 1.1

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*/
#include "CAAudioUnit.h"

#if !TARGET_OS_IPHONE
#if !defined(__COREAUDIO_USE_FLAT_INCLUDES__)
	#include <CoreServices/../Frameworks/CarbonCore.framework/Headers/Components.h>
	#include <dlfcn.h>
#else
	#include <Components.h>
#endif
#endif

#include "CAXException.h"
#include "CAReferenceCounted.h"
#include "AUOutputBL.h" //this is for the Preroll only

struct StackAUChannelInfo {
		StackAUChannelInfo (UInt32 inSize) : mChanInfo ((AUChannelInfo*)malloc (inSize)) {}
		~StackAUChannelInfo() { free (mChanInfo); }

	AUChannelInfo* mChanInfo;
};

// is this symbol is not defined then we use the default setting which is that fast dispatch
// is supported on a desktop environment
#ifndef CA_AU_USE_FAST_DISPATCH
	#define CA_AU_USE_FAST_DISPATCH !TARGET_OS_IPHONE
#endif

#if CA_AU_USE_FAST_DISPATCH
static void *LoadGetComponentInstanceStorage (void *inst);
#endif


class CAAudioUnit::AUState : public CAReferenceCounted  {
public:
	AUState (AudioComponent inComp)
						: mUnit(0), mNode (0)
						{
							OSStatus result = ::AudioComponentInstanceNew (inComp, &mUnit);
							if (result)
								throw result;
							Init();
						}

	AUState (const AUNode &inNode, const AudioUnit& inUnit)
						: mUnit (inUnit), mNode (inNode)
						{
							Init();
						}

	~AUState();

	AudioUnit			mUnit;
	AUNode				mNode;

	OSStatus			GetParameter(AudioUnitParameterID inID, AudioUnitScope scope, AudioUnitElement element,
											Float32 &outValue) const
	{
#if CA_AU_USE_FAST_DISPATCH
			if (mGetParamProc != NULL) {
				return (mGetParamProc) (mConnInstanceStorage, inID, scope, element, &outValue);
			}
#endif
		return AudioUnitGetParameter(mUnit, inID, scope, element, &outValue);
	}

	OSStatus			SetParameter(AudioUnitParameterID inID, AudioUnitScope scope, AudioUnitElement element,
											Float32 value, UInt32 bufferOffsetFrames)
	{
#if CA_AU_USE_FAST_DISPATCH
			if (mSetParamProc != NULL) {
				return (mSetParamProc) (mConnInstanceStorage, inID, scope, element, value, bufferOffsetFrames);
			}
#endif
			return AudioUnitSetParameter(mUnit, inID, scope, element, value, bufferOffsetFrames);
	}

	OSStatus			Render (AudioUnitRenderActionFlags *  ioActionFlags,
								const AudioTimeStamp *        inTimeStamp,
								UInt32                        inOutputBusNumber,
								UInt32                        inNumberFrames,
								AudioBufferList *             ioData)
	{
#if CA_AU_USE_FAST_DISPATCH
		if (mRenderProc != NULL) {
			return (mRenderProc) (mConnInstanceStorage, ioActionFlags, inTimeStamp, inOutputBusNumber, inNumberFrames, ioData);
		}
#endif
		return AudioUnitRender(mUnit, ioActionFlags, inTimeStamp, inOutputBusNumber, inNumberFrames, ioData);
	}

	OSStatus		MIDIEvent (UInt32					inStatus,
								UInt32					inData1,
								UInt32					inData2,
								UInt32					inOffsetSampleFrame)
	{
#if !TARGET_OS_WIN32
#if CA_AU_USE_FAST_DISPATCH
		if (mMIDIEventProc != NULL) {
			return (mMIDIEventProc) (mConnInstanceStorage, inStatus, inData1, inData2, inOffsetSampleFrame);
		}
#endif
		return MusicDeviceMIDIEvent (mUnit, inStatus, inData1, inData2, inOffsetSampleFrame);
#else	// ON WINDOWS _ NO MIDI EVENT dispatch
		return paramErr;
#endif
	}

	OSStatus				StartNote (MusicDeviceInstrumentID	inInstrument,
									MusicDeviceGroupID			inGroupID,
									NoteInstanceID *			outNoteInstanceID,
									UInt32						inOffsetSampleFrame,
									const MusicDeviceNoteParams * inParams)
	{
#if !TARGET_OS_WIN32
#if CA_AU_USE_FAST_DISPATCH
		if (mStartNoteProc != NULL) {
			return (mStartNoteProc) (mConnInstanceStorage, inInstrument, inGroupID, outNoteInstanceID, inOffsetSampleFrame, inParams);
		}
#endif
		return MusicDeviceStartNote (mUnit, inInstrument, inGroupID, outNoteInstanceID, inOffsetSampleFrame, inParams);
#else
		return paramErr;
#endif
	}
	OSStatus				StopNote (MusicDeviceGroupID		inGroupID,
									NoteInstanceID				inNoteInstanceID,
									UInt32						inOffsetSampleFrame)
	{
#if !TARGET_OS_WIN32
#if CA_AU_USE_FAST_DISPATCH
		if (mStopNoteProc != NULL) {
			return (mStopNoteProc) (mConnInstanceStorage, inGroupID, inNoteInstanceID, inOffsetSampleFrame);
		}
#endif
		return MusicDeviceStopNote (mUnit, inGroupID, inNoteInstanceID, inOffsetSampleFrame);
#else
		return paramErr;
#endif
	}

private:
	// get the fast dispatch pointers
	void Init()
	{
#if CA_AU_USE_FAST_DISPATCH
		UInt32 size = sizeof(AudioUnitRenderProc);
		if (AudioUnitGetProperty(mUnit, kAudioUnitProperty_FastDispatch,
								kAudioUnitScope_Global, kAudioUnitRenderSelect,
								&mRenderProc, &size) != noErr)
			mRenderProc = NULL;

		size = sizeof(AudioUnitGetParameterProc);
		if (AudioUnitGetProperty(mUnit, kAudioUnitProperty_FastDispatch,
								kAudioUnitScope_Global, kAudioUnitGetParameterSelect,
								&mGetParamProc, &size) != noErr)
			mGetParamProc = NULL;

		size = sizeof(AudioUnitSetParameterProc);
		if (AudioUnitGetProperty(mUnit, kAudioUnitProperty_FastDispatch,
								kAudioUnitScope_Global, kAudioUnitSetParameterSelect,
								&mSetParamProc, &size) != noErr)
			mSetParamProc = NULL;

		size = sizeof(MusicDeviceMIDIEventProc);
		if (AudioUnitGetProperty(mUnit, kAudioUnitProperty_FastDispatch,
								kAudioUnitScope_Global, kMusicDeviceMIDIEventSelect,
								&mMIDIEventProc, &size) != noErr)
			mMIDIEventProc = NULL;

		size = sizeof(MusicDeviceStartNoteProc);
		if (AudioUnitGetProperty(mUnit, kAudioUnitProperty_FastDispatch,
								kAudioUnitScope_Global, kMusicDeviceStartNoteSelect,
								&mStartNoteProc, &size) != noErr)
			mStartNoteProc = NULL;

		size = sizeof(MusicDeviceStopNoteProc);
		if (AudioUnitGetProperty(mUnit, kAudioUnitProperty_FastDispatch,
								kAudioUnitScope_Global, kMusicDeviceStopNoteSelect,
								&mStopNoteProc, &size) != noErr)
			mStopNoteProc = NULL;

		if (mRenderProc || mGetParamProc || mSetParamProc || mMIDIEventProc || mStartNoteProc || mStopNoteProc) {
			mConnInstanceStorage = LoadGetComponentInstanceStorage ( mUnit );
		} else
			mConnInstanceStorage = NULL;
#else
		mConnInstanceStorage = NULL;
#endif
	}

#if CA_AU_USE_FAST_DISPATCH
	AudioUnitRenderProc			mRenderProc;
	AudioUnitGetParameterProc	mGetParamProc;
	AudioUnitSetParameterProc	mSetParamProc;
	MusicDeviceMIDIEventProc	mMIDIEventProc;
	MusicDeviceStartNoteProc	mStartNoteProc;
	MusicDeviceStopNoteProc		mStopNoteProc;
#endif

	void *						mConnInstanceStorage;

private:
		// get the compiler to tell us when we do a bad thing!!!
	AUState () {}
	AUState (const AUState&);
	AUState& operator= (const AUState&);
};


CAAudioUnit::AUState::~AUState ()
{
	if (mUnit && (mNode == 0)) {
		::AudioComponentInstanceDispose (mUnit);
	}
	mNode = 0;
	mUnit = 0;
}

OSStatus		CAAudioUnit::Open (const CAComponent& inComp, CAAudioUnit &outUnit)
{
	try {
		outUnit = inComp;
		return noErr;
	} catch (OSStatus res) {
		return res;
	} catch (...) {
		return -1;
	}
}

CAAudioUnit::CAAudioUnit (const AudioUnit& inUnit)
	: mComp (inUnit), mDataPtr (new AUState (kCAAU_DoNotKnowIfAUNode, inUnit))
{
}

CAAudioUnit::CAAudioUnit (const CAComponent& inComp)
	: mComp (inComp), mDataPtr (new AUState (mComp.Comp()))
{
}

CAAudioUnit::CAAudioUnit (const AUNode &inNode, const AudioUnit& inUnit)
	: mComp (inUnit), mDataPtr(new AUState (inNode, inUnit))
{
}

CAAudioUnit::~CAAudioUnit ()
{
	Close();
}

void		CAAudioUnit::Close()
{
	if (mDataPtr) {
		mDataPtr->release();
		mDataPtr = NULL;
	}
}

CAAudioUnit&	CAAudioUnit::operator= (const CAAudioUnit &a)
{
	if (mDataPtr != a.mDataPtr) {
		if (mDataPtr)
			mDataPtr->release();

		if ((mDataPtr = a.mDataPtr) != NULL)
			mDataPtr->retain();

		mComp = a.mComp;
	}

	return *this;
}

bool			CAAudioUnit::operator== (const CAAudioUnit& y) const
{
	if (mDataPtr == y.mDataPtr) return true;
	AudioUnit au1 = mDataPtr ? mDataPtr->mUnit : 0;
	AudioUnit au2 = y.mDataPtr ? y.mDataPtr->mUnit : 0;
	return au1 == au2;
}

bool			CAAudioUnit::operator== (const AudioUnit& y) const
{
	if (!mDataPtr) return false;
	return mDataPtr->mUnit == y;
}

OSStatus		CAAudioUnit::RemovePropertyListener (AudioUnitPropertyID		inID,
												AudioUnitPropertyListenerProc	inProc,
												void *							inProcUserData)
{
		// we call this first. If it fails we call the old API as the failure can
		// mean that the AU doesn't implement that selector.
	OSStatus result = AudioUnitRemovePropertyListenerWithUserData(AU(), inID,
									inProc, inProcUserData);
	#if !__LP64__ && !TARGET_OS_IPHONE
		if (result) result = AudioUnitRemovePropertyListener (AU(), inID, inProc);
	#endif
	return result;
}

#pragma mark __State Management

bool			CAAudioUnit::IsValid () const
{
	return mDataPtr ? mDataPtr->mUnit != 0 : false;
}

AudioUnit		CAAudioUnit::AU() const
{
	return mDataPtr ? mDataPtr->mUnit : 0;
}

AUNode			CAAudioUnit::GetAUNode () const
{
	return mDataPtr ? mDataPtr->mNode : 0;
}

#pragma mark __Format Handling

bool		CAAudioUnit::CanDo (	int 				inChannelsIn,
									int 				inChannelsOut) const
{
	// this is the default assumption of an audio effect unit
	Boolean* isWritable = 0;
	UInt32	dataSize = 0;
		// lets see if the unit has any channel restrictions
	OSStatus result = AudioUnitGetPropertyInfo (AU(),
									kAudioUnitProperty_SupportedNumChannels,
									kAudioUnitScope_Global, 0,
									&dataSize, isWritable); //don't care if this is writable

		// if this property is NOT implemented an FX unit
		// is expected to deal with same channel valance in and out
	if (result)
	{
		if ((Comp().Desc().IsEffect() && inChannelsIn == inChannelsOut)
			|| (Comp().Desc().IsOffline() && inChannelsIn == inChannelsOut))
		{
			return true;
		}
		else
		{
			// the au should either really tell us about this
			// or we will assume the worst
			return false;
		}
	}

	StackAUChannelInfo info (dataSize);

	result = GetProperty (kAudioUnitProperty_SupportedNumChannels,
							kAudioUnitScope_Global, 0,
							info.mChanInfo, &dataSize);
	if (result) { return false; }

	return ValidateChannelPair (inChannelsIn, inChannelsOut, info.mChanInfo, (dataSize / sizeof (AUChannelInfo)));
}

int    CAAudioUnit::GetChannelInfo (AUChannelInfo** chaninfo, UInt32& cnt)
{
    // this is the default assumption of an audio effect unit
    Boolean* isWritable = 0;
    UInt32	dataSize = 0;
    // lets see if the unit has any channel restrictions
    OSStatus result = AudioUnitGetPropertyInfo (AU(),
                                                kAudioUnitProperty_SupportedNumChannels,
                                                kAudioUnitScope_Global, 0,
                                                &dataSize, isWritable); //don't care if this is writable

    // if this property is NOT implemented an FX unit
    // is expected to deal with same channel valance in and out

    if (result)
    {
        if (Comp().Desc().IsEffect())
        {
            return 1;
        }
        else if (Comp().Desc().IsGenerator() || Comp().Desc().IsMusicDevice()) {
            // directly query Bus Formats
            // Note that that these may refer to different subBusses
            // (eg. Kick, Snare,.. on a Drummachine)
            // eventually the Bus-Name for each configuration should be exposed
            // for the User to select..

            UInt32 elCountIn, elCountOut;

            if (GetElementCount (kAudioUnitScope_Input, elCountIn)) return -1;
            if (GetElementCount (kAudioUnitScope_Output, elCountOut)) return -1;

            cnt = std::max(elCountIn, elCountOut);

            *chaninfo = (AUChannelInfo*) malloc (sizeof (AUChannelInfo) * cnt);

            for (unsigned int i = 0; i < elCountIn; ++i) {
                UInt32 numChans;
                if (NumberChannels (kAudioUnitScope_Input, i, numChans)) return -1;
                (*chaninfo)[i].inChannels = numChans;
            }
            for (unsigned int i = elCountIn; i < cnt; ++i) {
                (*chaninfo)[i].inChannels = 0;
            }

            for (unsigned int i = 0; i < elCountOut; ++i) {
                UInt32 numChans;
                if (NumberChannels (kAudioUnitScope_Output, i, numChans)) return -1;
                (*chaninfo)[i].outChannels = numChans;
            }
            for (unsigned int i = elCountOut; i < cnt; ++i) {
                (*chaninfo)[i].outChannels = 0;
            }
            return 0;
        }
        else
        {
            // the au should either really tell us about this
            // or we will assume the worst
            return -1;
        }
    }

    *chaninfo = (AUChannelInfo*) malloc (dataSize);
    cnt = dataSize / sizeof (AUChannelInfo);

    result = GetProperty (kAudioUnitProperty_SupportedNumChannels,
                          kAudioUnitScope_Global, 0,
                          *chaninfo, &dataSize);

    if (result) { return -1; }
    return 0;
}

bool	CAAudioUnit::ValidateChannelPair (int 				inChannelsIn,
										int 				inChannelsOut,
										const AUChannelInfo * info,
										UInt32				numChanInfo) const
{
// we've the following cases (some combinations) to test here:
/*
>0		An explicit number of channels on either side
0		that side (generally input!) has no elements
-1		wild card:
-1,-1	any num channels as long as same channels on in and out
-1,-2	any num channels channels on in and out - special meaning
-2+ 	indicates total num channs AU can handle
			- elements configurable to any num channels,
			- element count in scope must be writable
*/

	//now chan layout can contain -1 for either scope (ie. doesn't care)
	for (unsigned int i = 0; i < numChanInfo; ++i)
	{
			//less than zero on both sides - check for special attributes
		if ((info[i].inChannels < 0) && (info[i].outChannels < 0))
		{
				// these are our wild card matches
			if (info[i].inChannels == -1 && info[i].outChannels == -1) {
				if (inChannelsIn && inChannelsOut) {
					if (inChannelsOut == inChannelsIn)
						return true;
				} else
					return true; // if one of these is zero, then a -1 means any
			}
			else if ((info[i].inChannels == -1 && info[i].outChannels == -2)
					|| (info[i].inChannels == -2 && info[i].outChannels == -1))
			{
				return true;
			}
				// these are our total num channels matches
				// element count MUST be writable
			else {
				bool outWrite = false; bool inWrite = false;
				IsElementCountWritable (kAudioUnitScope_Output, outWrite);
				IsElementCountWritable (kAudioUnitScope_Input, inWrite);
				if (inWrite && outWrite) {
					if ((inChannelsOut <= abs(info[i].outChannels))
						&& (inChannelsIn <= abs(info[i].inChannels)))
					{
						return true;
					}
				}
			}
		}

			// special meaning on input, specific num on output
		else if (info[i].inChannels < 0) {
			if (info[i].outChannels == inChannelsOut)
			{
					// can do any in channels
				if (info[i].inChannels == -1) {
					return true;
				}
					// total chans on input
				else {
					bool inWrite = false;
					IsElementCountWritable (kAudioUnitScope_Input, inWrite);
					if (inWrite && (inChannelsIn <= abs(info[i].inChannels))) {
						return true;
					}
				}
			}
		}

			// special meaning on output, specific num on input
		else if (info[i].outChannels < 0) {
			if (info[i].inChannels == inChannelsIn)
			{
					// can do any out channels
				if (info[i].outChannels == -1) {
					return true;
				}
					// total chans on output
				else {
					bool outWrite = false;
					IsElementCountWritable (kAudioUnitScope_Output, outWrite);
					if (outWrite && (inChannelsOut <= abs(info[i].outChannels))) {
						return true;
					}
				}
			}
		}

			// both chans in struct >= 0 - thus has to explicitly match
		else if ((info[i].inChannels == inChannelsIn) && (info[i].outChannels == inChannelsOut)) {
			return true;
		}

			// now check to see if a wild card on the args (inChannelsIn or inChannelsOut chans is zero) is found
			// tells us to match just one side of the scopes
		else if (inChannelsIn == 0) {
			if (info[i].outChannels == inChannelsOut) {
				return true;
			}
		}
		else if (inChannelsOut == 0) {
			if (info[i].inChannels == inChannelsIn) {
				return true;
			}
		}
	}

	return false;
}

static
bool CheckDynCount (SInt32 inTotalChans, const CAAUChanHelper &inHelper)
{
	int totalChans = 0;
	for (unsigned int i = 0; i < inHelper.mNumEls; ++i)
		totalChans += inHelper.mChans[i];
	return (totalChans <= inTotalChans);
}

bool	CAAudioUnit::CheckOneSide (const CAAUChanHelper		&inHelper,
									bool					checkOutput,
									const AUChannelInfo		*info,
									UInt32					numInfo) const
{
		// now we can use the wildcard option (see above impl) to see if this matches
	for (unsigned int el = 0; el < inHelper.mNumEls; ++el) {
		bool testAlready = false;
		for (unsigned int i = 0; i < el; ++i) {
			if (inHelper.mChans[i] == inHelper.mChans[el]) {
				testAlready = true;
				break;
			}
		}
		if (!testAlready) {
			if (checkOutput) {
				if (!ValidateChannelPair (0, inHelper.mChans[el], info, numInfo)) return false;
			} else {
				if (!ValidateChannelPair (inHelper.mChans[el], 0, info, numInfo)) return false;
			}
		}
	}
	return true;
}

bool		CAAudioUnit::CanDo (const CAAUChanHelper		&inputs,
								const CAAUChanHelper		&outputs) const

{
// first check our state
		// huh!
	if (inputs.mNumEls == 0 && outputs.mNumEls == 0) return false;

	UInt32 elCount;
	if (GetElementCount (kAudioUnitScope_Input, elCount)) { return false; }
	if (elCount != inputs.mNumEls) return false;

	if (GetElementCount (kAudioUnitScope_Output, elCount)) { return false; }
	if (elCount != outputs.mNumEls) return false;

// (1) special cases (effects and sources (generators and instruments) only)
	UInt32	dataSize = 0;
	if (GetPropertyInfo (kAudioUnitProperty_SupportedNumChannels,
									kAudioUnitScope_Global, 0, &dataSize, NULL) != noErr)
	{
		if (Comp().Desc().IsEffect() || Comp().Desc().IsOffline()) {
			UInt32 numChan = outputs.mNumEls > 0 ? outputs.mChans[0] : inputs.mChans[0];
			for (unsigned int in = 0; in < inputs.mNumEls; ++in)
				if (numChan != inputs.mChans[in]) return false;
			for (unsigned int out = 0; out < outputs.mNumEls; ++out)
				if (numChan != outputs.mChans[out]) return false;
			return true;
		}

			// in this case, all the channels have to match the current config
		if (Comp().Desc().IsGenerator() || Comp().Desc().IsMusicDevice()) {
			for (unsigned int in = 0; in < inputs.mNumEls; ++in) {
				UInt32 chan;
				if (NumberChannels (kAudioUnitScope_Input, in, chan)) return false;
				if (chan != UInt32(inputs.mChans[in])) return false;
			}
			for (unsigned int out = 0; out < outputs.mNumEls; ++out) {
				UInt32 chan;
				if (NumberChannels (kAudioUnitScope_Output, out, chan)) return false;
				if (chan != UInt32(outputs.mChans[out])) return false;
			}
			return true;
		}

			// if we get here we can't determine anything about channel capabilities
		return false;
	}

	StackAUChannelInfo info (dataSize);

	if (GetProperty (kAudioUnitProperty_SupportedNumChannels,
							kAudioUnitScope_Global, 0,
							info.mChanInfo, &dataSize) != noErr)
	{
		return false;
	}

	int numInfo = dataSize / sizeof(AUChannelInfo);

// (2) Test for dynamic capability (or no elements on that scope)
	SInt32 dynInChans = 0;
	if (ValidateDynamicScope (kAudioUnitScope_Input, dynInChans, info.mChanInfo, numInfo)) {
		if (CheckDynCount (dynInChans, inputs) == false) return false;
	}

	SInt32 dynOutChans = 0;
	if (ValidateDynamicScope (kAudioUnitScope_Output, dynOutChans, info.mChanInfo, numInfo)) {
		if (CheckDynCount (dynOutChans, outputs) == false) return false;
	}

	if (dynOutChans && dynInChans) { return true; }

// (3)	Just need to test one side
	if (dynInChans || (inputs.mNumEls == 0)) {
		return CheckOneSide (outputs, true, info.mChanInfo, numInfo);
	}

	if (dynOutChans || (outputs.mNumEls == 0)) {
		return CheckOneSide (inputs, false, info.mChanInfo, numInfo);
	}

// (4) - not a dynamic AU, has ins and outs, and has channel constraints so we test every possible pairing
	for (unsigned int in = 0; in < inputs.mNumEls; ++in)
	{
		bool testInAlready = false;
		for (unsigned int i = 0; i < in; ++i) {
			if (inputs.mChans[i] == inputs.mChans[in]) {
				testInAlready = true;
				break;
			}
		}
		if (!testInAlready) {
			for (unsigned int out = 0; out < outputs.mNumEls; ++out) {
					// try to save a little bit and not test the same pairing multiple times...
				bool testOutAlready = false;
				for (unsigned int i = 0; i < out; ++i) {
					if (outputs.mChans[i] == outputs.mChans[out]) {
						testOutAlready = true;
						break;
					}
				}
				if (!testOutAlready) {
					if (!ValidateChannelPair (inputs.mChans[in], outputs.mChans[out],info.mChanInfo, numInfo)) {
						return false;
					}
				}
			}
		}
	}

	return true;
}

bool		CAAudioUnit::SupportsNumChannels () const
{
	// this is the default assumption of an audio effect unit
	Boolean* isWritable = 0;
	UInt32	dataSize = 0;
		// lets see if the unit has any channel restrictions
	OSStatus result = AudioUnitGetPropertyInfo (AU(),
									kAudioUnitProperty_SupportedNumChannels,
									kAudioUnitScope_Global, 0,
									&dataSize, isWritable); //don't care if this is writable

		// if this property is NOT implemented an FX unit
		// is expected to deal with same channel valance in and out
	if (result) {
		if (Comp().Desc().IsEffect() || Comp().Desc().IsOffline())
			return true;
	}
	return result == noErr;
}

OSStatus		CAAudioUnit::GetChannelLayoutTags (AudioUnitScope 	inScope,
										AudioUnitElement 			inEl,
										ChannelTagVector			&outChannelVector) const
{
	if (HasChannelLayouts (inScope, inEl) == false) return kAudioUnitErr_InvalidProperty;

	UInt32 dataSize;
	OSStatus result = AudioUnitGetPropertyInfo (AU(),
								kAudioUnitProperty_SupportedChannelLayoutTags,
								inScope, inEl,
								&dataSize, NULL);

	if (result) return result;

		// OK lets get our channel layouts and see if the one we want is present
	AudioChannelLayoutTag* info = (AudioChannelLayoutTag*)malloc (dataSize);
	result = AudioUnitGetProperty (AU(),
							kAudioUnitProperty_SupportedChannelLayoutTags,
							inScope, inEl,
							info, &dataSize);
	if (result) goto home;

	outChannelVector.erase (outChannelVector.begin(), outChannelVector.end());
	for (unsigned int i = 0; i < (dataSize / sizeof (AudioChannelLayoutTag)); ++i)
		outChannelVector.push_back (info[i]);

home:
	free (info);
	return result;
}

bool		CAAudioUnit::HasChannelLayouts (AudioUnitScope 		inScope,
										AudioUnitElement 		inEl) const
{
	OSStatus result = AudioUnitGetPropertyInfo (AU(),
									kAudioUnitProperty_SupportedChannelLayoutTags,
									inScope, inEl,
									NULL, NULL);
	return !result;
}

bool		CAAudioUnit::HasChannelLayout (AudioUnitScope 		inScope,
											AudioUnitElement 		inEl) const
{
	Boolean writable;
	UInt32 size;

	return AudioUnitGetPropertyInfo (AU(),
									kAudioUnitProperty_AudioChannelLayout,
									inScope, inEl,
									&size, &writable) == noErr;
}

OSStatus	CAAudioUnit::GetChannelLayout (AudioUnitScope 		inScope,
										AudioUnitElement 		inEl,
										CAAudioChannelLayout	&outLayout) const
{
	UInt32 size;
	OSStatus result = AudioUnitGetPropertyInfo (AU(), kAudioUnitProperty_AudioChannelLayout,
									inScope, inEl, &size, NULL);
	if (result) return result;

	AudioChannelLayout *layout = (AudioChannelLayout*)malloc (size);

	ca_require_noerr (result = AudioUnitGetProperty (AU(), kAudioUnitProperty_AudioChannelLayout,
									inScope, inEl, layout, &size), home);

	outLayout = CAAudioChannelLayout (layout);

home:
	free (layout);
	return result;
}

OSStatus	CAAudioUnit::SetChannelLayout (AudioUnitScope 		inScope,
									AudioUnitElement 			inEl,
									const CAAudioChannelLayout 		&inLayout)
{
	OSStatus result = AudioUnitSetProperty (AU(),
									kAudioUnitProperty_AudioChannelLayout,
									inScope, inEl,
									inLayout, inLayout.Size());
	return result;
}

OSStatus	CAAudioUnit::SetChannelLayout (AudioUnitScope 			inScope,
											AudioUnitElement 		inEl,
											const AudioChannelLayout		&inLayout,
											UInt32					inSize)
{
	OSStatus result = AudioUnitSetProperty (AU(),
									kAudioUnitProperty_AudioChannelLayout,
									inScope, inEl,
									&inLayout, inSize);
	return result;
}

OSStatus		CAAudioUnit::ClearChannelLayout (AudioUnitScope	inScope,
											AudioUnitElement	inEl)
{
	return AudioUnitSetProperty (AU(),
							kAudioUnitProperty_AudioChannelLayout,
							inScope, inEl, NULL, 0);
}

OSStatus	CAAudioUnit::GetFormat (AudioUnitScope				inScope,
									AudioUnitElement			inEl,
									AudioStreamBasicDescription	&outFormat) const
{
	UInt32 dataSize = sizeof (AudioStreamBasicDescription);
	return AudioUnitGetProperty (AU(), kAudioUnitProperty_StreamFormat,
								inScope, inEl,
								&outFormat, &dataSize);
}

OSStatus	CAAudioUnit::SetFormat (AudioUnitScope						inScope,
									AudioUnitElement					inEl,
									const AudioStreamBasicDescription	&inFormat)
{
	return AudioUnitSetProperty (AU(), kAudioUnitProperty_StreamFormat,
								inScope, inEl,
								const_cast<AudioStreamBasicDescription*>(&inFormat),
								sizeof (AudioStreamBasicDescription));
}

OSStatus	CAAudioUnit::GetSampleRate (AudioUnitScope		inScope,
										AudioUnitElement	inEl,
										Float64				&outRate) const
{
	UInt32 dataSize = sizeof (Float64);
	return AudioUnitGetProperty (AU(), kAudioUnitProperty_SampleRate,
								inScope, inEl,
								&outRate, &dataSize);
}

OSStatus	CAAudioUnit::SetSampleRate (AudioUnitScope		inScope,
										AudioUnitElement	inEl,
										Float64				inRate)
{
	AudioStreamBasicDescription desc;
	OSStatus result = GetFormat (inScope, inEl, desc);
	if (result) return result;
	desc.mSampleRate = inRate;
	return SetFormat (inScope, inEl, desc);
}

OSStatus	CAAudioUnit::SetSampleRate (Float64			inSampleRate)
{
	OSStatus result;

	UInt32 elCount;
	ca_require_noerr (result = GetElementCount(kAudioUnitScope_Input, elCount), home);
	if (elCount) {
		for (unsigned int i = 0; i < elCount; ++i) {
			ca_require_noerr (result = SetSampleRate (kAudioUnitScope_Input, i, inSampleRate), home);
		}
	}

	ca_require_noerr (result = GetElementCount(kAudioUnitScope_Output, elCount), home);
	if (elCount) {
		for (unsigned int i = 0; i < elCount; ++i) {
			ca_require_noerr (result = SetSampleRate (kAudioUnitScope_Output, i, inSampleRate), home);
		}
	}

home:
	return result;
}

OSStatus	CAAudioUnit::NumberChannels (AudioUnitScope		inScope,
										AudioUnitElement	inEl,
										UInt32				&outChans) const
{
	AudioStreamBasicDescription desc;
	OSStatus result = GetFormat (inScope, inEl, desc);
	if (!result)
		outChans = desc.mChannelsPerFrame;
	return result;
}

OSStatus	CAAudioUnit::SetNumberChannels (AudioUnitScope	inScope,
										AudioUnitElement	inEl,
										UInt32				inChans)
{
			// set this as the output of the AU
	CAStreamBasicDescription desc;
	OSStatus result = GetFormat (inScope, inEl, desc);
		if (result) return result;
	desc.ChangeNumberChannels (inChans, desc.IsInterleaved());
	result = SetFormat (inScope, inEl, desc);
	return result;
}

OSStatus		CAAudioUnit::IsElementCountWritable (AudioUnitScope inScope, bool &outWritable) const
{
	Boolean isWritable;
	UInt32 outDataSize;
	OSStatus result = GetPropertyInfo (kAudioUnitProperty_ElementCount, inScope, 0, &outDataSize, &isWritable);
	if (result)
		return result;
	outWritable = isWritable ? true : false;
	return noErr;
}

OSStatus		CAAudioUnit::GetElementCount (AudioUnitScope inScope, UInt32 &outCount) const
{
	UInt32 propSize = sizeof(outCount);
	return GetProperty (kAudioUnitProperty_ElementCount, inScope, 0, &outCount, &propSize);
}

OSStatus		CAAudioUnit::SetElementCount (AudioUnitScope inScope, UInt32 inCount)
{
	return SetProperty (kAudioUnitProperty_ElementCount, inScope, 0, &inCount, sizeof(inCount));
}

bool			CAAudioUnit::HasDynamicScope (AudioUnitScope inScope, SInt32 &outTotalNumChannels) const
{
	// ok - now we need to check the AU's capability here.
	// this is the default assumption of an audio effect unit
	Boolean* isWritable = 0;
	UInt32	dataSize = 0;
	OSStatus result = GetPropertyInfo (kAudioUnitProperty_SupportedNumChannels,
								kAudioUnitScope_Global, 0,
								&dataSize, isWritable); //don't care if this is writable

		// AU has to explicitly tell us about this.
	if (result) return false;

	StackAUChannelInfo info (dataSize);

	result = GetProperty (kAudioUnitProperty_SupportedNumChannels,
							kAudioUnitScope_Global, 0,
							info.mChanInfo, &dataSize);
	if (result) return false;

	return ValidateDynamicScope (inScope, outTotalNumChannels, info.mChanInfo, (dataSize / sizeof(AUChannelInfo)));
}

// as we've already checked that the element count is writable
// the following conditions will match this..
/*
-1, -2 ->	signifies no restrictions
-2, -1 ->	signifies no restrictions -> in this case outTotalNumChannels == -1 (any num channels)

-N 	(where N is less than -2), signifies the total channel count on the scope side (in or out)
*/
bool	CAAudioUnit::ValidateDynamicScope (AudioUnitScope		inScope,
											SInt32				&outTotalNumChannels,
											const AUChannelInfo *info,
											UInt32				numInfo) const
{
	bool writable = false;
	OSStatus result = IsElementCountWritable (inScope, writable);
	if (result || (writable == false))
		return false;

	//now chan layout can contain -1 for either scope (ie. doesn't care)
	for (unsigned int i = 0; i < numInfo; ++i)
	{
		// lets test the special wild card case first...
		// this says the AU can do any num channels on input or output - for eg. Matrix Mixer
		if (((info[i].inChannels == -1) && (info[i].outChannels == -2))
			|| ((info[i].inChannels == -2) && (info[i].outChannels == -1)))
		{
			outTotalNumChannels = -1;
			return true;
		}

		// ok lets now test our special case....
		if (inScope == kAudioUnitScope_Input) {
				// isn't dynamic on this side at least
			if (info[i].inChannels >= 0)
				continue;

			if (info[i].inChannels < -2) {
				outTotalNumChannels = abs (info[i].inChannels);
				return true;
			}
		}

		else if (inScope == kAudioUnitScope_Output) {
				// isn't dynamic on this side at least
			if (info[i].outChannels >= 0)
				continue;

			if (info[i].outChannels < -2) {
				outTotalNumChannels = abs (info[i].outChannels);
				return true;
			}
		}

		else {
			break; // wrong scope was specified
		}
	}

	return false;
}

OSStatus	CAAudioUnit::ConfigureDynamicScope (AudioUnitScope 		inScope,
											UInt32 					inNumElements,
											UInt32 					*inChannelsPerElement,
											Float64 				inSampleRate)
{
	SInt32 numChannels = 0;
	bool isDyamic = HasDynamicScope (inScope, numChannels);
	if (isDyamic == false)
		return kAudioUnitErr_InvalidProperty;

	//lets to a sanity check...
	// if numChannels == -1, then it can do "any"...
	if (numChannels > 0) {
		SInt32 count = 0;
		for (unsigned int i = 0; i < inNumElements; ++i)
			count += inChannelsPerElement[i];
		if (count > numChannels)
			return kAudioUnitErr_InvalidPropertyValue;
	}

	OSStatus result = SetElementCount (inScope, inNumElements);
	if (result)
		return result;

	for (unsigned int i = 0; i < inNumElements; ++i) {
		CAStreamBasicDescription desc;
		result = GetFormat (inScope, i, desc);
			if (result) return result;
		desc.ChangeNumberChannels (inChannelsPerElement[i], desc.IsInterleaved());
		desc.mSampleRate = inSampleRate;
		result = SetFormat (inScope, i, desc);
		if (result)
			return result;
	}
	return noErr;
}

#pragma mark __Properties

bool		CAAudioUnit::CanBypass () const
{
	Boolean outWritable;
	OSStatus result = AudioUnitGetPropertyInfo (AU(), kAudioUnitProperty_BypassEffect,
									kAudioUnitScope_Global, 0,
									NULL, &outWritable);
	return (!result && outWritable);
}

bool		CAAudioUnit::GetBypass 		() const
{
	UInt32 dataSize = sizeof (UInt32);
	UInt32 outBypass;
	OSStatus result = AudioUnitGetProperty (AU(), kAudioUnitProperty_BypassEffect,
								kAudioUnitScope_Global, 0,
								&outBypass, &dataSize);
	return (result ? false : outBypass);
}

OSStatus	CAAudioUnit::SetBypass 		(bool	inBypass) const
{
	UInt32 bypass = inBypass ? 1 : 0;
	return AudioUnitSetProperty (AU(), kAudioUnitProperty_BypassEffect,
								kAudioUnitScope_Global, 0,
								&bypass, sizeof (UInt32));
}

OSStatus	CAAudioUnit::GetMaxFramesPerSlice (UInt32& outMaxFrames) const
{
	UInt32 dataSize = sizeof(outMaxFrames);
	return AudioUnitGetProperty (AU(), kAudioUnitProperty_MaximumFramesPerSlice,
								kAudioUnitScope_Global, 0,
								&outMaxFrames, &dataSize);
}

OSStatus	CAAudioUnit::SetMaxFramesPerSlice (UInt32 inMaxFrames)
{
	return AudioUnitSetProperty (AU(), kAudioUnitProperty_MaximumFramesPerSlice,
								 kAudioUnitScope_Global, 0,
								 &inMaxFrames, sizeof (UInt32));
}

Float64		CAAudioUnit::Latency () const
{
	Float64 secs;
	UInt32 size = sizeof(secs);
	if (GetProperty (kAudioUnitProperty_Latency, kAudioUnitScope_Global, 0, &secs, &size))
		return 0;
	return secs;
}

OSStatus	CAAudioUnit::GetAUPreset (CFPropertyListRef &outData) const
{
	UInt32 dataSize = sizeof(outData);
	return AudioUnitGetProperty (AU(), kAudioUnitProperty_ClassInfo,
								kAudioUnitScope_Global, 0,
								&outData, &dataSize);
}

OSStatus	CAAudioUnit::SetAUPreset (CFPropertyListRef &inData)
{
	return AudioUnitSetProperty (AU(), kAudioUnitProperty_ClassInfo,
								kAudioUnitScope_Global, 0,
								&inData, sizeof (CFPropertyListRef));
}

#if !TARGET_OS_IPHONE
OSStatus	CAAudioUnit::SetAUPresetFromDocument (CFPropertyListRef &inData)
{
	return AudioUnitSetProperty (AU(), kAudioUnitProperty_ClassInfoFromDocument,
								kAudioUnitScope_Global, 0,
								&inData, sizeof (CFPropertyListRef));
}
#endif

OSStatus	CAAudioUnit::GetPresentPreset (AUPreset &outData) const
{
	UInt32 dataSize = sizeof(outData);
	OSStatus result = AudioUnitGetProperty (AU(), kAudioUnitProperty_PresentPreset,
								kAudioUnitScope_Global, 0,
								&outData, &dataSize);
#if !TARGET_OS_IPHONE
#ifndef __LP64__
	if (result == kAudioUnitErr_InvalidProperty) {
		dataSize = sizeof(outData);
		result = AudioUnitGetProperty (AU(), kAudioUnitProperty_CurrentPreset,
									kAudioUnitScope_Global, 0,
									&outData, &dataSize);
		if (result == noErr) {
			// we now retain the CFString in the preset so for the client of this API
			// it is consistent (ie. the string should be released when done)
			if (outData.presetName)
				CFRetain (outData.presetName);
		}
	}
#endif
#endif
	return result;
}

OSStatus	CAAudioUnit::SetPresentPreset (AUPreset &inData)
{
	OSStatus result = AudioUnitSetProperty (AU(), kAudioUnitProperty_PresentPreset,
								kAudioUnitScope_Global, 0,
								&inData, sizeof (AUPreset));
#if !TARGET_OS_IPHONE
#ifndef __LP64__
	if (result == kAudioUnitErr_InvalidProperty) {
		result = AudioUnitSetProperty (AU(), kAudioUnitProperty_CurrentPreset,
								kAudioUnitScope_Global, 0,
								&inData, sizeof (AUPreset));
	}
#endif
#endif
	return result;
}

bool		CAAudioUnit::HasCustomView () const
{
#if !TARGET_OS_IPHONE
	UInt32 dataSize = 0;
	OSStatus result = -4/*unimpErr*/;
#ifndef __LP64__
	result = GetPropertyInfo(kAudioUnitProperty_GetUIComponentList,
                                        kAudioUnitScope_Global, 0,
                                        &dataSize, NULL);
#endif
	if (result || !dataSize) {
		dataSize = 0;
		result = GetPropertyInfo(kAudioUnitProperty_CocoaUI,
                                        kAudioUnitScope_Global, 0,
                                        &dataSize, NULL);
		if (result || !dataSize)
			return false;
	}
	return true;
#else
	return false;
#endif

}

OSStatus		CAAudioUnit::GetParameter(AudioUnitParameterID inID, AudioUnitScope scope, AudioUnitElement element,
											Float32 &outValue) const
{
	return mDataPtr ? mDataPtr->GetParameter (inID, scope, element, outValue) : static_cast<OSStatus>(paramErr);
}

OSStatus		CAAudioUnit::SetParameter(AudioUnitParameterID inID, AudioUnitScope scope, AudioUnitElement element,
											Float32 value, UInt32 bufferOffsetFrames)
{
	return mDataPtr ? mDataPtr->SetParameter (inID, scope, element, value, bufferOffsetFrames) : static_cast<OSStatus>(paramErr);
}

OSStatus		CAAudioUnit::MIDIEvent (UInt32			inStatus,
								UInt32					inData1,
								UInt32					inData2,
								UInt32					inOffsetSampleFrame)
{
	return mDataPtr ? mDataPtr->MIDIEvent (inStatus, inData1, inData2, inOffsetSampleFrame) : paramErr;
}

OSStatus	CAAudioUnit::StartNote (MusicDeviceInstrumentID		inInstrument,
									MusicDeviceGroupID			inGroupID,
									NoteInstanceID *			outNoteInstanceID,
									UInt32						inOffsetSampleFrame,
									const MusicDeviceNoteParams * inParams)
{
	return mDataPtr ? mDataPtr->StartNote (inInstrument, inGroupID, outNoteInstanceID, inOffsetSampleFrame, inParams)
					: paramErr;
}

OSStatus	CAAudioUnit::StopNote (MusicDeviceGroupID		inGroupID,
									NoteInstanceID				inNoteInstanceID,
									UInt32						inOffsetSampleFrame)
{
	return mDataPtr ? mDataPtr->StopNote (inGroupID, inNoteInstanceID, inOffsetSampleFrame) : paramErr;
}


#pragma mark __Render

OSStatus		CAAudioUnit::Render (AudioUnitRenderActionFlags 			* ioActionFlags,
												const AudioTimeStamp 		* inTimeStamp,
												UInt32						inOutputBusNumber,
												UInt32						inNumberFrames,
												AudioBufferList				* ioData)
{
	return mDataPtr ? mDataPtr->Render (ioActionFlags, inTimeStamp, inOutputBusNumber, inNumberFrames, ioData) : static_cast<OSStatus>(paramErr);
}

extern "C" OSStatus
AudioUnitProcess (					AudioUnit						inUnit,
									AudioUnitRenderActionFlags *	ioActionFlags,
									const AudioTimeStamp *			inTimeStamp,
									UInt32							inNumberFrames,
									AudioBufferList *				ioData);

OSStatus		CAAudioUnit::Process (AudioUnitRenderActionFlags 			& ioActionFlags,
												const AudioTimeStamp 		& inTimeStamp,
												UInt32						inNumberFrames,
												AudioBufferList				& ioData)
{
#if defined(__MAC_10_7) || defined(__IPHONE_4_0)
	return AudioUnitProcess (AU(), &ioActionFlags, &inTimeStamp, inNumberFrames, &ioData);
#else
	return -4/*unimpErr*/;
#endif
}

extern "C" OSStatus
AudioUnitProcessMultiple (			AudioUnit						inUnit,
									AudioUnitRenderActionFlags *	ioActionFlags,
									const AudioTimeStamp *			inTimeStamp,
									UInt32							inNumberFrames,
									UInt32							inNumberInputBufferLists,
									const AudioBufferList **		inInputBufferLists,
									UInt32							inNumberOutputBufferLists,
									AudioBufferList **				ioOutputBufferLists);

OSStatus		CAAudioUnit::ProcessMultiple (AudioUnitRenderActionFlags 	& ioActionFlags,
									const AudioTimeStamp					& inTimeStamp,
									UInt32									inNumberFrames,
									UInt32									inNumberInputBufferLists,
									const AudioBufferList **				inInputBufferLists,
									UInt32									inNumberOutputBufferLists,
									AudioBufferList **						ioOutputBufferLists)
{
#if defined(__MAC_10_7) || defined(__IPHONE_4_0)
	return AudioUnitProcessMultiple (AU(), &ioActionFlags, &inTimeStamp, inNumberFrames,
				inNumberInputBufferLists, inInputBufferLists, inNumberOutputBufferLists, ioOutputBufferLists);
#else
	return -4/*unimpErr*/;
#endif
}

#pragma mark __CAAUChanHelper

CAAUChanHelper::CAAUChanHelper(const CAAudioUnit &inAU, AudioUnitScope inScope)
	:mChans(NULL), mNumEls(0), mDidAllocate(false)
{
	UInt32 elCount;
	if (inAU.GetElementCount (inScope, elCount)) return;
	if (elCount > kStaticElCount) {
		mChans = new UInt32[elCount];
		mDidAllocate = true;
		memset (mChans, 0, sizeof(int) * elCount);
	} else {
		mChans = mStaticChans;
		memset (mChans, 0, sizeof(int) * kStaticElCount);
	}
	for (unsigned int i = 0; i < elCount; ++i) {
		UInt32 numChans;
		if (inAU.NumberChannels (inScope, i, numChans)) return;
		mChans[i] = numChans;
	}
	mNumEls = elCount;
}

CAAUChanHelper::CAAUChanHelper(UInt32 inMaxElems)
	: mNumEls(inMaxElems), mDidAllocate(false)
{
	if (inMaxElems > kStaticElCount) {
		mChans = new UInt32[inMaxElems];
		mDidAllocate = true;
		memset (mChans, 0, sizeof(int) * inMaxElems);
	} else {
		mChans = mStaticChans;
		memset (mChans, 0, sizeof(int) * kStaticElCount);
	}
}

CAAUChanHelper::~CAAUChanHelper()
{
	if (mDidAllocate) delete [] mChans;
}

CAAUChanHelper&		CAAUChanHelper::operator= (const CAAUChanHelper &c)
{
	if (mDidAllocate) delete [] mChans;
	if (c.mDidAllocate) {
		mChans = new UInt32[c.mNumEls];
		mDidAllocate = true;
	} else {
		mDidAllocate = false;
		mChans = mStaticChans;
	}
	memcpy (mChans, c.mChans, c.mNumEls * sizeof(int));

	return *this;
}


#pragma mark __Print Utilities

void		CAAudioUnit::Print (FILE* file) const
{
	fprintf (file, "AudioUnit:%p\n", AU());
	if (IsValid()) {
		fprintf (file, "\tnode=%ld\t", (long)GetAUNode()); Comp().Print (file);
	}
}

#if CA_AU_USE_FAST_DISPATCH
// Handle  GetComponentInstanceStorage(ComponentInstance aComponentInstance)
static void *LoadGetComponentInstanceStorage (void *inst)
{
	typedef void* (*GetComponentInstanceStorageProc)(void* aComponentInstance);
	static GetComponentInstanceStorageProc sGetComponentInstanceStorageProc = NULL;

	static int sDoCSLoad = 1;
	if (sDoCSLoad) {
		sDoCSLoad = 0;
		void *theImage = dlopen("/System/Library/Frameworks/CoreServices.framework/CoreServices", RTLD_LAZY);
		if (!theImage) return NULL;

		sGetComponentInstanceStorageProc = (GetComponentInstanceStorageProc) dlsym(theImage, "GetComponentInstanceStorage");
	}
	if (sGetComponentInstanceStorageProc)
		return (*sGetComponentInstanceStorageProc)(inst);
	return NULL;
}
#endif