hang in brace expansion

hang in brace expansion

[Mikael Magnusson]

Doing {^@..a} will hang indefinitely (where ^@ is a literal null
character). The problem is in xpandbraces in glob.c,
        for (; cend >= cstart; cend--) {
cend and cstart are unsigned types and cstart is 0. I'm a bit tired at
the moment so I can't figure out a nice way to write this loop that
always works. The value cend is used inside the loop, cstart isn't. I
suppose we could just add if (cend == 0) break; at the last line of
the loop?

-- 
Mikael Magnusson

PATCH: Fix {^@..a} hanging

[Mikael Magnusson]

This should work for all possible cases, and is fine since we always
want to enter the loop at least once anyway.

---
 Src/glob.c | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

diff --git a/Src/glob.c b/Src/glob.c
index 3bf66e4..bf758d4 100644
--- a/Src/glob.c
+++ b/Src/glob.c
@@ -2228,7 +2228,7 @@ xpandbraces(LinkList list, LinkNode *np)
 	    uremnode(list, node);
 	    strp = str - str3;
 	    lenalloc = strp + strlen(str2+1) + 1;
-	    for (; cend >= cstart; cend--) {
+	    do {
 #ifdef MULTIBYTE_SUPPORT
 		char *ncptr;
 		int nclen;
@@ -2248,7 +2248,7 @@ xpandbraces(LinkList list, LinkNode *np)
 		insertlinknode(list, last, p);
 		if (rev)	/* decreasing:  add in reverse order. */
 		    last = nextnode(last);
-	    }
+	    } while (cend-- > cstart);
 	    *np = nextnode(olast);
 	    return;
 	}
-- 
1.9.0