Function CMBlockBufferCreateWithMemoryBlock 

pub unsafe extern "C" fn CMBlockBufferCreateWithMemoryBlock(
    structureAllocator: CFAllocatorRef,
    memoryBlock: *mut c_void,
    blockLength: usize,
    blockAllocator: CFAllocatorRef,
    customBlockSource: *const CMBlockBufferCustomBlockSource,
    offsetToData: usize,
    dataLength: usize,
    flags: CMBlockBufferFlags,
    blockBufferOut: *mut CMBlockBufferRef,
) -> OSStatus