Just FYI: In the cluster code I needed to decode from data buffers that might not coincide with frame boundaries, but without having anything like the AsyncIOs "unread" feature.
qpid/framing/FrameDecoder.h is a simple and I believe efficient solution to this problem. It provides a buffer (growable but never larger than the largest frame decoded) to save a frame fragment found at the end of a read buffer. The rest of the frame is copied from the front of the next read buffer when it arrives. Only fragmented frames are ever copied, at most one per read buffer. The buffer does get reallocated but the number of allocations will be small. Cheers, Alan.
