PublicUtility/CAAudioBufferList.h

/*
     File: CAAudioBufferList.h 
 Abstract:  Part of CoreAudio Utility Classes  
  Version: 1.0 
  
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*/
#if !defined(__CAAudioBufferList_h__)
#define __CAAudioBufferList_h__
 
//=============================================================================
//  Includes
//=============================================================================
 
//  System Includes
#if !defined(__COREAUDIO_USE_FLAT_INCLUDES__)
    #include <CoreAudio/CoreAudioTypes.h>
#else
    #include <CoreAudioTypes.h>
#endif
 
//=============================================================================
//  Types
//=============================================================================
 
typedef AudioBufferList*    AudioBufferListPtr;
 
//=============================================================================
//  CAAudioBufferList
//=============================================================================
 
struct  CAAudioBufferList
{
 
//  Construction/Destruction
public:
    static AudioBufferList* Create(UInt32 inNumberBuffers);
    static void             Destroy(AudioBufferList* inBufferList);
    static UInt32           CalculateByteSize(UInt32 inNumberBuffers);
 
//  Operations
public:
    static UInt32           GetTotalNumberChannels(const AudioBufferList& inBufferList);
    static bool             GetBufferForChannel(const AudioBufferList& inBufferList, UInt32 inChannel, UInt32& outBufferNumber, UInt32& outBufferChannel);
    static void             Clear(AudioBufferList& outBufferList);
    static void             Copy(const AudioBufferList& inSource, UInt32 inStartingSourceChannel, AudioBufferList& outDestination, UInt32 inStartingDestinationChannel);
    static void             CopyChannel(const AudioBuffer& inSource, UInt32 inSourceChannel, AudioBuffer& outDestination, UInt32 inDestinationChannel);
    static void             Sum(const AudioBufferList& inSourceBufferList, AudioBufferList& ioSummedBufferList);
    static bool             HasData(AudioBufferList& inBufferList);
#if CoreAudio_Debug
    static void             PrintToLog(const AudioBufferList& inBufferList);
#endif
 
//  Constants
public:
    static AudioBufferList  sEmptyBufferList;
 
};
 
// Declare a variably-sized AudioBufferList on the stack
#define STACK_ABL(name, nbufs) \
    ThrowIf(nbufs < 1 || nbufs > 64, CAException(kAudio_ParamError), "STACK_ABL: invalid number of buffers") \
    const size_t name##_ByteSize = sizeof(AudioBufferList) + (nbufs - 1) * sizeof(AudioBuffer); \
    AudioBufferList &name = *(AudioBufferList *)alloca(name##_ByteSize); \
    name.mNumberBuffers = nbufs;
 
 
#endif