Re: segfault in strftime

[Peter Stephenson <pws@xxxxxxx>]

On Fri, 26 Feb 2010 16:07:49 +0100
Vincent Lefevre <vincent@xxxxxxxxxx> wrote:
> > $ strftime "%a %d.%m.%Y %H:%M:%S" -1
> > strftime: -1: success
> 
> Concerning this one:
> 
>     secs = (time_t)strtoul(argv[1], &endptr, 10);
>     if (secs == (time_t)ULONG_MAX) {
>         zwarnnam(nam, "%s: %e", argv[1], errno);
>         return 1;
>     } else if (*endptr != '\0') {
>         zwarnnam(nam, "%s: invalid decimal number", argv[1]);
>         return 1;
>     }
> 
> ULONG_MAX is not necessarily an error! You need to check errno.

I hope we don't need to handle the case sizeof(time_t) > sizeof(unsigned
long).  It's certainly not typical.

Index: Src/Modules/datetime.c
===================================================================
RCS file: /cvsroot/zsh/zsh/Src/Modules/datetime.c,v
retrieving revision 1.19
diff -p -u -r1.19 datetime.c
--- Src/Modules/datetime.c	26 Feb 2010 14:25:05 -0000	1.19
+++ Src/Modules/datetime.c	26 Feb 2010 15:15:12 -0000
@@ -111,8 +111,9 @@ bin_strftime(char *nam, char **argv, Opt
     if (OPT_ISSET(ops, 'r'))
 	return reverse_strftime(nam, argv, scalar, OPT_ISSET(ops, 'q'));
 
+    errno = 0;
     secs = (time_t)strtoul(argv[1], &endptr, 10);
-    if (secs == (time_t)ULONG_MAX) {
+    if (secs == (time_t)ULONG_MAX && errno != 0) {
 	zwarnnam(nam, "%s: %e", argv[1], errno);
 	return 1;
     } else if (*endptr != '\0') {



-- 
Peter Stephenson <pws@xxxxxxx>            Software Engineer
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