bool SFB::Audio::RingBuffer::Allocate(const AudioFormat& format, size_t capacityFrames)
{
// Only non-interleaved formats are supported
if(format.IsInterleaved())
return false;
Deallocate();
// Round up to the next power of two
capacityFrames = NextPowerOfTwo((uint32_t)capacityFrames);
mFormat = format;
mCapacityFrames = capacityFrames;
mCapacityFramesMask = capacityFrames - 1;
size_t capacityBytes = format.FrameCountToByteCount(capacityFrames);
// One memory allocation holds everything- first the pointers followed by the deinterleaved channels
size_t allocationSize = (capacityBytes + sizeof(uint8_t *)) * format.mChannelsPerFrame;
uint8_t *memoryChunk = (uint8_t *)malloc(allocationSize);
if(nullptr == memoryChunk)
return false;
// Zero the entire allocation
memset(memoryChunk, 0, allocationSize);
// Assign the pointers and channel buffers
mBuffers = (uint8_t **)memoryChunk;
memoryChunk += format.mChannelsPerFrame * sizeof(uint8_t *);
for(UInt32 i = 0; i < format.mChannelsPerFrame; ++i) {
mBuffers[i] = memoryChunk;
memoryChunk += capacityBytes;
}
mReadPointer = 0;
mWritePointer = 0;
return true;
}
