Fix segfaults when parsing bdiff hunks in mpatch.decode() and .patchedsize() - fix off by 11 when checking if there are more hunks (found by Maris Fogels) - bail out if start is greater than end - check if new hunk starts after start/end/len block of current hunk as the pointer can wrap around on very large values, reproducible with import mpatch; mpatch.patchedsize(12, 'x'*12)

foo renamed from bar:26d3ca0dfd18e44d796b564e38dd173c9668d3a9
   rev    offset  length   base linkrev nodeid       p1           p2
     0         0       6      0       0 26d3ca0dfd18 000000000000 000000000000
     1         6       7      1       1 d267bddd54f7 26d3ca0dfd18 000000000000