PATCH Re: infinite loop in prompt expansion

["Bart Schaefer" <schaefer@xxxxxxxxxxxxxxxx>]

On Sep 30,  4:51pm, Laurent Wacrenier wrote:
} Subject: infinite loop in prompt expansion
}
} Prompt truncation may enter in infinite loop within litteral escape
} sequence :
} 
} % print -P '%{%8<..<%/%}'
} (don't give the hand back and spend all CPU time)

It shouldn't infinte loop, but I'd like to point out that it also is not
intended to do anything useful.

%{ ... %} means that the string inside the braces is treated as zero width
for purposes of computing the size of the prompt.  Truncating a zero width 
string is a no-op.

Hence the fix (which is probably not going to make you happy) is this:

Index: prompt.c
===================================================================
RCS file: /extra/cvsroot/zsh/zsh-4.0/Src/prompt.c,v
retrieving revision 1.6
diff -c -r1.6 prompt.c
--- prompt.c	1 Sep 2002 16:47:38 -0000	1.6
+++ prompt.c	30 Sep 2002 18:31:15 -0000
@@ -856,6 +856,10 @@
 	    addbufspc(1);
 	    *bp++ = *fm++;
 	}
+	if (dontcount) {
+	    bp = buf + w;
+	    return 1;
+	}
 	if (!*fm)
 	    return 0;
 	if (bp - buf == w && truncchar == ']') {

-- 
Bart Schaefer                                 Brass Lantern Enterprises
http://www.well.com/user/barts              http://www.brasslantern.com

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