TPCircularBuffer+AudioBufferList.h

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//
//  TPCircularBuffer+AudioBufferList.h
//  Circular/Ring buffer implementation
//
//  https://github.com/michaeltyson/TPCircularBuffer
//
//  Created by Michael Tyson on 20/03/2012.
//
//  Copyright (C) 2012-2013 A Tasty Pixel
//
//  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.
//

#ifndef TPCircularBuffer_AudioBufferList_h
#define TPCircularBuffer_AudioBufferList_h

#ifdef __cplusplus
extern "C" {
#endif

#include "TPCircularBuffer.h"
#include <AudioToolbox/AudioToolbox.h>

#define kTPCircularBufferCopyAll UINT32_MAX

typedef struct {
    AudioTimeStamp timestamp;
    UInt32 totalLength;
    AudioBufferList bufferList;
} TPCircularBufferABLBlockHeader;

    
AudioBufferList *TPCircularBufferPrepareEmptyAudioBufferList(TPCircularBuffer *buffer, int numberOfBuffers, int bytesPerBuffer, const AudioTimeStamp *timestamp);

AudioBufferList *TPCircularBufferPrepareEmptyAudioBufferListWithAudioFormat(TPCircularBuffer *buffer, const AudioStreamBasicDescription *audioFormat, UInt32 frameCount, const AudioTimeStamp *timestamp);

void TPCircularBufferProduceAudioBufferList(TPCircularBuffer *buffer, const AudioTimeStamp *inTimestamp);

bool TPCircularBufferCopyAudioBufferList(TPCircularBuffer *buffer, const AudioBufferList *bufferList, const AudioTimeStamp *timestamp, UInt32 frames, const AudioStreamBasicDescription *audioFormat);

static __inline__ __attribute__((always_inline)) AudioBufferList *TPCircularBufferNextBufferList(TPCircularBuffer *buffer, AudioTimeStamp *outTimestamp) {
    int32_t dontcare; // Length of segment is contained within buffer list, so we can ignore this
    TPCircularBufferABLBlockHeader *block = (TPCircularBufferABLBlockHeader*)TPCircularBufferTail(buffer, &dontcare);
    if ( !block ) {
        if ( outTimestamp ) {
            memset(outTimestamp, 0, sizeof(AudioTimeStamp));
        }
        return NULL;
    }
    if ( outTimestamp ) {
        memcpy(outTimestamp, &block->timestamp, sizeof(AudioTimeStamp));
    }
    return &block->bufferList;
}

AudioBufferList *TPCircularBufferNextBufferListAfter(TPCircularBuffer *buffer, const AudioBufferList *bufferList, AudioTimeStamp *outTimestamp);

static __inline__ __attribute__((always_inline)) void TPCircularBufferConsumeNextBufferList(TPCircularBuffer *buffer) {
    int32_t dontcare;
    TPCircularBufferABLBlockHeader *block = (TPCircularBufferABLBlockHeader*)TPCircularBufferTail(buffer, &dontcare);
    if ( !block ) return;
    TPCircularBufferConsume(buffer, block->totalLength);
}

void TPCircularBufferConsumeNextBufferListPartial(TPCircularBuffer *buffer, int framesToConsume, const AudioStreamBasicDescription *audioFormat);

void TPCircularBufferDequeueBufferListFrames(TPCircularBuffer *buffer, UInt32 *ioLengthInFrames, const AudioBufferList *outputBufferList, AudioTimeStamp *outTimestamp, const AudioStreamBasicDescription *audioFormat);

UInt32 TPCircularBufferPeek(TPCircularBuffer *buffer, AudioTimeStamp *outTimestamp, const AudioStreamBasicDescription *audioFormat);

UInt32 TPCircularBufferPeekContiguous(TPCircularBuffer *buffer, AudioTimeStamp *outTimestamp, const AudioStreamBasicDescription *audioFormat, UInt32 contiguousToleranceSampleTime);
    
UInt32 TPCircularBufferPeekContiguousWrapped(TPCircularBuffer *buffer, AudioTimeStamp *outTimestamp, const AudioStreamBasicDescription *audioFormat, UInt32 contiguousToleranceSampleTime, UInt32 wrapPoint);

UInt32 TPCircularBufferGetAvailableSpace(TPCircularBuffer *buffer, const AudioStreamBasicDescription *audioFormat);
    
#ifdef __cplusplus
}
#endif

#endif