@param dst Destination buffer
@param back Number of bytes back to start copying (i.e. the initial size of
the overlapping window); must be > 0
@param cnt Number of bytes to copy; must be >= 0
@note cnt > back is valid, this will copy the bytes we just copied,
thus creating a repeating pattern with a period length of back.
Overlapping memcpy() implementation.
@param dst Destination buffer @param back Number of bytes back to start copying (i.e. the initial size of the overlapping window); must be > 0 @param cnt Number of bytes to copy; must be >= 0
@note cnt > back is valid, this will copy the bytes we just copied, thus creating a repeating pattern with a period length of back.