[src/trunk]: src/lib/libc/time Fix reversed oveflow check.

[christos <christos%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/14c1d9b6c6c4
branches:  trunk
changeset: 760880:14c1d9b6c6c4
user:      christos <christos%NetBSD.org@localhost>
date:      Sat Jan 15 15:42:10 2011 +0000

description:
Fix reversed oveflow check.

diffstat:

 lib/libc/time/localtime.c |  12 ++++++++----
 1 files changed, 8 insertions(+), 4 deletions(-)

diffs (42 lines):

diff -r 1bc0a1cc5cd2 -r 14c1d9b6c6c4 lib/libc/time/localtime.c
--- a/lib/libc/time/localtime.c Sat Jan 15 13:54:52 2011 +0000
+++ b/lib/libc/time/localtime.c Sat Jan 15 15:42:10 2011 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: localtime.c,v 1.53 2011/01/15 12:31:57 martin Exp $    */
+/*     $NetBSD: localtime.c,v 1.54 2011/01/15 15:42:10 christos Exp $  */
 
 /*
 ** This file is in the public domain, so clarified as of
@@ -10,7 +10,7 @@
 #if 0
 static char    elsieid[] = "@(#)localtime.c    8.9";
 #else
-__RCSID("$NetBSD: localtime.c,v 1.53 2011/01/15 12:31:57 martin Exp $");
+__RCSID("$NetBSD: localtime.c,v 1.54 2011/01/15 15:42:10 christos Exp $");
 #endif
 #endif /* LIBC_SCCS and not lint */
 
@@ -1704,8 +1704,10 @@
        int     number0;
 
        number0 = *number;
+       if (delta < 0 ? number0 < INT_MIN - delta : INT_MAX - delta < number0)
+                 return 1;
        *number += delta;
-       return (*number < number0) != (delta < 0);
+       return 0;
 }
 
 static int
@@ -1714,8 +1716,10 @@
        long    number0;
 
        number0 = *number;
+       if (delta < 0 ? number0 < LONG_MIN - delta : LONG_MAX - delta < number0)
+                 return 1;
        *number += delta;
-       return (*number < number0) != (delta < 0);
+       return 0;
 }
 
 static int