Bugs with exclusion using file paths.

[Peter Stephenson <pws@pwstephenson.fsnet.co.uk>]

Fixes for the bugs I mentioned earlier.  For globbing, a top level ~
is handled specially, leading to these two.  Getting exclusion to work
properly is extremely complicated, so I can't promise this is the last of
it.  Maybe someone out there knows better algorithms.


1. Some idiot messed up the exclusion of absolute paths when he was optimizing
the pattern matching code.

5:32% print /*
/bin /boot /data /dev /etc /home /lib /lost+found /mnt /opt /proc /root /sbin /tmp /usr /var /windows
5:32% print /*~/b*
/*~/b*

The problem is that / is treated as an end of path segment, which it isn't
in the exclusion part, so it first parses /*~ as a string, then finds
garbage at the end.


2. print **/*~(.)# dumped core

This is because the pattern is handled in two parts.  The path before the
last slash is tried first, then the final bit is matched against whatever's
in the directory.  However, the exclusion is supposed to exclude the entire
pattern, treating / as an ordinary character.  Hence the pre-path has to be
prepended for the exclusion matching only.  I forgot to do this with the
pointer to the start of the pattern, so pointer arithmetic was off.  I
didn't fix up the variable holding the total length of the pattern, either.
This is all a recipe for disaster, and I love to know how else to do it.

We need some real globbing tests to pick up this sort of thing; pattern
matching in tests is insensitive to it.


Index: Src/pattern.c
===================================================================
RCS file: /home/pws/CVSROOT/projects/zsh/Src/pattern.c,v
retrieving revision 1.6
diff -u -r1.6 pattern.c
--- Src/pattern.c	2000/02/23 18:29:27	1.6
+++ Src/pattern.c	2000/03/26 22:05:05
@@ -486,7 +486,8 @@
 
     while (*patparse == Bar ||
 	   (isset(EXTENDEDGLOB) && *patparse == Tilde &&
-	    !memchr(patendseg, patparse[1], patendseglen))) {
+	    (patparse[1] == '/' ||
+	     !memchr(patendseg, patparse[1], patendseglen)))) {
 	int tilde = *patparse++ == Tilde;
 	long gfnode = 0, newbr;
 
@@ -634,7 +635,7 @@
 
     starter = chain = 0;
     while (!memchr(patendseg, *patparse, patendseglen) ||
-	   (*patparse == Tilde &&
+	   (*patparse == Tilde && patparse[1] != '/' &&
 	    memchr(patendseg, patparse[1], patendseglen))) {
 	if (isset(EXTENDEDGLOB) &&
 	    ((!isset(SHGLOB) &&
@@ -811,6 +812,7 @@
 	 */
 	if (kshchar || (memchr(patendstr, *patparse, patendstrlen) &&
 			(*patparse != Tilde ||
+			 patparse[1] == '/' ||
 			 !memchr(patendseg, patparse[1], patendseglen))))
 	    break;
 
@@ -1754,7 +1756,8 @@
 			while ((ret = patmatch(P_OPERAND(scan)))) {
 			    unsigned char *syncpt;
 			    char savchar, *testptr;
-			    int savforce = forceerrs;
+			    char *savpatinstart = patinstart;
+			    int savforce = forceerrs, savpatinlen = patinlen;
 			    forceerrs = -1;
 			    savglobdots = globdots;
 			    matchederrs = errsfound;
@@ -1799,7 +1802,8 @@
 					zalloc(pathpos + patinlen);
 				    strcpy(buf, pathbuf);
 				    strcpy(buf + pathpos, patinput);
-				    patinput = buf;
+				    patinput = patinstart = buf;
+				    patinlen += pathpos;
 				}
 				if (patmatch(opnd)) {
 				    ret = 0;
@@ -1810,8 +1814,11 @@
 				     */
 				    parsfound = savparsfound;
 				}
-				if (buf)
+				if (buf) {
 				    zfree(buf, pathpos + patinlen);
+				    patinstart = savpatinstart;
+				    patinlen = savpatinlen;
+				}
 				if (!ret)
 				    break;
 				next = PATNEXT(next);

-- 
Peter Stephenson <pws@pwstephenson.fsnet.co.uk>