Re: simple regex for highlighting _/* fails

On Wed, Apr 11, 2007 at 03:04:24PM +0200, Rado S wrote:
> Moin moin,
> 
> the PCRE author spotted the error quicky, and I verified the patch
> works, for details see http://www.pcre.org/pcre.txt, middle of section
> "How pcre_exec() returns captured substrings", patch attached:
> 
> ----- Forwarded message from Philip Hazel <[email protected]> -----
> > >         int offsets[6];
> > >         int offsets_size = ARRAY_SIZE(offsets);
> > > 
> > >         while (pcre_exec(regex->re, regex->extra, ptr, strlen(ptr), 0, 0, offsets, offsets_size) > 0) {
> > 
> > Instead of >0, that should be >= 0 because a value of 0 is returned if
> > there is a match but not enough room in the offsets to store all the
> > capturing parentheses. That's the bug. An offsets vector that is only 6
> > long has room for just the main match plus one set of capturing parens.
> ----- End forwarded message -----
>
> --- torg/src/regex.c	Tue Mar 27 20:25:48 2007
> +++ tgo/src/regex.c	Wed Apr 11 14:40:36 2007
> @@ -162,7 +162,7 @@
>  #endif /* USE_CURSES */
>  	ptr = buf;
>  
> -	while (pcre_exec(regex->re, regex->extra, ptr, strlen(ptr), 0, 0, offsets, offsets_size) > 0) {
> +	while (pcre_exec(regex->re, regex->extra, ptr, strlen(ptr), 0, 0, offsets, offsets_size) >= 0) {
>  		/* we have a match */
>  		if (color >= 0) /* color the matching text */
>  			word_highlight_string(row, (ptr - buf) + offsets[0], offsets[1] - offsets[0], color);

thanks, fixed (also twice in misc.c:eat_re()) - I didn't bother mallocing
a big enough offsets[] as we are not interrested in the subpatterns.

urs
-- 
"Only whimps use tape backup: _real_ men just upload their important stuff
 on ftp, and let the rest of the world mirror it ;)" - Linus