AEUtilities.h

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//
//  AEUtilities.h
//  The Amazing Audio Engine
//
//  Created by Michael Tyson on 23/03/2012.
//
//  This software is provided 'as-is', without any express or implied
//  warranty.  In no event will the authors be held liable for any damages
//  arising from the use of this software.
//
//  Permission is granted to anyone to use this software for any purpose,
//  including commercial applications, and to alter it and redistribute it
//  freely, subject to the following restrictions:
//
//  1. The origin of this software must not be misrepresented; you must not
//     claim that you wrote the original software. If you use this software
//     in a product, an acknowledgment in the product documentation would be
//     appreciated but is not required.
//
//  2. Altered source versions must be plainly marked as such, and must not be
//     misrepresented as being the original software.
//
//  3. This notice may not be removed or altered from any source distribution.
//

#import <AudioToolbox/AudioToolbox.h>
#import <Foundation/Foundation.h>

#ifdef __cplusplus
extern "C" {
#endif

#pragma mark - AudioBufferList Utilities



AudioBufferList *AEAudioBufferListCreate(AudioStreamBasicDescription audioFormat, int frameCount);
#define AEAllocateAndInitAudioBufferList AEAudioBufferListCreate // Legacy alias

#define AEAudioBufferListCreateOnStack(name, audioFormat) \
    int name ## _numberBuffers = audioFormat.mFormatFlags & kAudioFormatFlagIsNonInterleaved \
                                    ? audioFormat.mChannelsPerFrame : 1; \
    char name ## _bytes[sizeof(AudioBufferList)+(sizeof(AudioBuffer)*(name ## _numberBuffers-1))]; \
    memset(&name ## _bytes, 0, sizeof(name ## _bytes)); \
    AudioBufferList * name = (AudioBufferList*)name ## _bytes; \
    name->mNumberBuffers = name ## _numberBuffers;

#define AEAudioBufferListCopyOnStack(name, sourceBufferList, offsetBytes) \
    char name ## _bytes[sizeof(AudioBufferList)+(sizeof(AudioBuffer)*(sourceBufferList->mNumberBuffers-1))]; \
    memcpy(name ## _bytes, sourceBufferList, sizeof(name ## _bytes)); \
    AudioBufferList * name = (AudioBufferList*)name ## _bytes; \
    for ( int i=0; i<name->mNumberBuffers; i++ ) { \
        name->mBuffers[i].mData = (char*)name->mBuffers[i].mData + offsetBytes; \
        name->mBuffers[i].mDataByteSize -= offsetBytes; \
    }

AudioBufferList *AEAudioBufferListCopy(const AudioBufferList *original);
#define AECopyAudioBufferList AEAudioBufferListCopy // Legacy alias

void AEAudioBufferListFree(AudioBufferList *bufferList);
#define AEFreeAudioBufferList AEAudioBufferListFree // Legacy alias

UInt32 AEAudioBufferListGetLength(const AudioBufferList *bufferList,
                                  AudioStreamBasicDescription audioFormat,
                                  int *oNumberOfChannels);
#define AEGetNumberOfFramesInAudioBufferList AEAudioBufferListGetLength // Legacy alias

void AEAudioBufferListSetLength(AudioBufferList *bufferList,
                                AudioStreamBasicDescription audioFormat,
                                UInt32 frames);

void AEAudioBufferListOffset(AudioBufferList *bufferList,
                             AudioStreamBasicDescription audioFormat,
                             UInt32 frames);

void AEAudioBufferListSilence(const AudioBufferList *bufferList,
                              AudioStreamBasicDescription audioFormat,
                              UInt32 offset,
                              UInt32 length);
    
static inline size_t AEAudioBufferListGetStructSize(const AudioBufferList *bufferList) {
    return sizeof(AudioBufferList) + (bufferList->mNumberBuffers-1) * sizeof(AudioBuffer);
}

#pragma mark - AudioStreamBasicDescription Utilities



extern const AudioStreamBasicDescription AEAudioStreamBasicDescriptionNonInterleavedFloatStereo;

extern const AudioStreamBasicDescription AEAudioStreamBasicDescriptionNonInterleaved16BitStereo;

extern const AudioStreamBasicDescription AEAudioStreamBasicDescriptionInterleaved16BitStereo;
    
typedef enum {
    AEAudioStreamBasicDescriptionSampleTypeFloat32, 
    AEAudioStreamBasicDescriptionSampleTypeInt16,   
    AEAudioStreamBasicDescriptionSampleTypeInt32    
} AEAudioStreamBasicDescriptionSampleType;

AudioStreamBasicDescription AEAudioStreamBasicDescriptionMake(AEAudioStreamBasicDescriptionSampleType sampleType,
                                                              BOOL interleaved,
                                                              int numberOfChannels,
                                                              double sampleRate);
    
void AEAudioStreamBasicDescriptionSetChannelsPerFrame(AudioStreamBasicDescription *audioDescription, int numberOfChannels);

#pragma mark - Time Utilities



void AETimeInit(void);

uint64_t AECurrentTimeInHostTicks(void);

double AECurrentTimeInSeconds(void);

uint64_t AEHostTicksFromSeconds(double seconds);

double AESecondsFromHostTicks(uint64_t ticks);

#pragma mark - Other Utilities



AudioComponentDescription AEAudioComponentDescriptionMake(OSType manufacturer, OSType type, OSType subtype);

BOOL AERateLimit(void);

#define AECheckOSStatus(result,operation) (_AECheckOSStatus((result),(operation),strrchr(__FILE__, '/')+1,__LINE__))
static inline BOOL _AECheckOSStatus(OSStatus result, const char *operation, const char* file, int line) {
    if ( result != noErr ) {
        if ( AERateLimit() ) {
            int fourCC = CFSwapInt32HostToBig(result);
            if ( isascii(((char*)&fourCC)[0]) && isascii(((char*)&fourCC)[1]) && isascii(((char*)&fourCC)[2]) ) {
                NSLog(@"%s:%d: %s: '%4.4s' (%d)", file, line, operation, (char*)&fourCC, (int)result);
            } else {
                NSLog(@"%s:%d: %s: %d", file, line, operation, (int)result);
            }
        }
        return NO;
    }
    return YES;
}
    
    
#ifdef __cplusplus
}
#endif