void TPCircularBufferProduceAudioBufferList(TPCircularBuffer *buffer, const AudioTimeStamp *inTimestamp) {
int32_t availableBytes;
TPCircularBufferABLBlockHeader *block = (TPCircularBufferABLBlockHeader*)TPCircularBufferHead(buffer, &availableBytes);
assert(block);
assert(!((unsigned long)block & 0xF) /* Beware unaligned accesses */);
assert(block->bufferList.mBuffers[0].mDataByteSize > 0);
if ( inTimestamp ) {
memcpy(&block->timestamp, inTimestamp, sizeof(AudioTimeStamp));
}
UInt32 calculatedLength = (UInt32)(((char*)block->bufferList.mBuffers[block->bufferList.mNumberBuffers-1].mData + block->bufferList.mBuffers[block->bufferList.mNumberBuffers-1].mDataByteSize) - (char*)block);
// Make sure whole buffer (including timestamp and length value) is 16-byte aligned in length
calculatedLength = (UInt32)align16byte(calculatedLength);
assert(calculatedLength <= block->totalLength && calculatedLength <= availableBytes);
block->totalLength = calculatedLength;
TPCircularBufferProduce(buffer, block->totalLength);
}
void TPCircularBufferProduceAudioBufferList(TPCircularBuffer *buffer) {
int32_t availableBytes;
AudioTimeStamp *timestamp = (AudioTimeStamp*)TPCircularBufferHead(buffer, &availableBytes);
UInt32 *totalLengthInBytes = (UInt32*)(timestamp+1);
AudioBufferList *list = (AudioBufferList*)(totalLengthInBytes+1);
UInt32 calculatedLength = ((char*)list->mBuffers[list->mNumberBuffers-1].mData + list->mBuffers[list->mNumberBuffers-1].mDataByteSize) - (char*)list;
assert(calculatedLength < *totalLengthInBytes && sizeof(AudioTimeStamp)+sizeof(UInt32)+calculatedLength <= availableBytes);
*totalLengthInBytes = calculatedLength;
TPCircularBufferProduce(buffer,
sizeof(AudioTimeStamp) +
sizeof(UInt32) +
*totalLengthInBytes);
}
bool TPCircularBufferCopyAudioBufferList(TPCircularBuffer *buffer, const AudioBufferList *bufferList, const AudioTimeStamp *inTimestamp) {
int bufferListSize = sizeof(AudioBufferList) + ((bufferList->mNumberBuffers-1) * sizeof(AudioBuffer));
int32_t availableBytes;
AudioTimeStamp *timestamp = (AudioTimeStamp*)TPCircularBufferHead(buffer, &availableBytes);
if ( availableBytes < sizeof(AudioTimeStamp) + bufferListSize ) return false;
// Store timestamp, followed by buffer list
if ( inTimestamp ) {
*timestamp = *inTimestamp;
} else {
memset(timestamp, 0, sizeof(AudioTimeStamp));
}
UInt32 *totalLengthInBytes = (UInt32*)(timestamp+1);
AudioBufferList *list = (AudioBufferList*)(totalLengthInBytes+1);
memcpy(list, bufferList, bufferListSize);
char *dataPtr = (char*)list + bufferListSize;
for ( int i=0; i<bufferList->mNumberBuffers; i++ ) {
// Find the next 16-byte aligned memory area
dataPtr = (char*)align16bit((long)dataPtr);
if ( (dataPtr + bufferList->mBuffers[i].mDataByteSize) - (char*)timestamp > availableBytes ) {
return false;
}
assert(bufferList->mBuffers[i].mData != NULL);
list->mBuffers[i].mData = dataPtr;
memcpy(dataPtr, bufferList->mBuffers[i].mData, bufferList->mBuffers[i].mDataByteSize);
dataPtr += bufferList->mBuffers[i].mDataByteSize;
}
*totalLengthInBytes = (dataPtr-(char*)list);
TPCircularBufferProduce(buffer, dataPtr-(char*)timestamp);
return true;
}
