| |||||||||||||
|
| |||||||||||||
Off by one?Off by one?Posted May 29, 2003 22:21 UTC (Thu) by raph (guest, #326)In reply to: strlcpy() by nas Parent article: strlcpy()
I'm pretty sure you have an off-by-one error there - your code can write up to (size+1) bytes of dst, while from the paper it looks like the correct semantics are to write up to size bytes only - so that strlcat(buf, src, sizeof(buf)) is safe.
(Log in to post comments)
Off by one? Posted May 30, 2003 4:40 UTC (Fri) by ncm (subscriber, #165) [Link] I agree, Neil's is buggy. Walk through it with size == 1. It clobbers one beyond the end of the input array.I wonder if we should bother about what to do if size == 0. Mine crashes spectacularly, which is a Good Thing. Getting within 15% of memcpy is pretty damn good, in my estimation. Of course I didn't read Linus's version, or OpenBSD's; that would be cheating, and I would be tainted besides. Of course now that I have been told, via cleanroom methods, I can adjust mine to be equally fast, and maybe (one can hope) actually identical to both Linus's and OpenBSD's.
Off by one? Posted May 30, 2003 16:28 UTC (Fri) by tjc (guest, #137) [Link] Getting within 15% of memcpy is pretty damn good, in my estimation. Of course I didn't read Linus's version, or OpenBSD's; that would be cheating, and I would be tainted besides. Of course now that I have been told, via cleanroom methods, I can adjust mine to be equally fast, and maybe (one can hope) actually identical to both Linus's and OpenBSD's.You're probably going to have to copy more than one char at a time to match memcpy() for speed.
|
|
||||||||||||