[Guvante]

You could also just restrict the pointers in the normal way but to two times the size of the buffer. So instead of wrapping at N you wrap at 2*N.

You are only encoding 1 bit of data (first or second) so adding more data than that by allowing unsigned integer overflow is just an optimization, not fundamentally necessary.

[mark-r]

If you do that then the size() function becomes a problem. The original implementation relies on unsigned integer wrap-around to give the proper result when write < read.

[caf]

That is fairly easy to fix, though. Add N to the size value you get until its non-negative.