Module Name: src
Committed By: christos
Date: Fri Jan 14 23:35:07 UTC 2011
Modified Files:
src/lib/libc/time: Makefile localtime.c zdump.c zic.c
Log Message:
don't depend on integer oveflow wrapping to detect it. From Paul Eggert in
the tz mailing list.
To generate a diff of this commit:
cvs rdiff -u -r1.1.1.1 -r1.2 src/lib/libc/time/Makefile
cvs rdiff -u -r1.51 -r1.52 src/lib/libc/time/localtime.c
cvs rdiff -u -r1.17 -r1.18 src/lib/libc/time/zdump.c
cvs rdiff -u -r1.26 -r1.27 src/lib/libc/time/zic.c
Please note that diffs are not public domain; they are subject to the
copyright notices on the relevant files.
Modified files:
Index: src/lib/libc/time/Makefile
diff -u src/lib/libc/time/Makefile:1.1.1.1 src/lib/libc/time/Makefile:1.2
--- src/lib/libc/time/Makefile:1.1.1.1 Sun Oct 25 12:20:16 2009
+++ src/lib/libc/time/Makefile Fri Jan 14 18:35:07 2011
@@ -110,6 +110,10 @@
# -TTZ_DOMAINDIR=\"/path\" to use "/path" for gettext directory;
# the default is system-supplied, typically "/usr/lib/locale"
# $(GCC_DEBUG_FLAGS) if you are using GCC and want lots of checking
+# $(GCC_OVERFLOW_FLAGS) if you are using GCC 3.4 or later.
+# If you are using a compiler other than GCC, and if it defaults to
+# undefined behavior on integer overflow, then you need to specify a flag
+# saying that integer arithmetic is supposed to wrap around on overflow.
# -DNO_RUN_TIME_WARNINGS_ABOUT_YEAR_2000_PROBLEMS_THANK_YOU=1
# if you do not want run time warnings about formats that may cause
# year 2000 grief
@@ -120,6 +124,7 @@
-Wall -Wcast-qual -Wconversion -Wmissing-prototypes \
-Wnested-externs -Wpointer-arith -Wshadow \
-Wtraditional # -Wstrict-prototypes -Wwrite-strings
+GCC_OVERFLOW_FLAGS = -fwrapv
#
# If you want to use System V compatibility code, add
# -DUSG_COMPAT
@@ -386,7 +391,7 @@
public: $(ENCHILADA)
make maintainer-clean
- make "CFLAGS=$(GCC_DEBUG_FLAGS)"
+ make "CFLAGS=$(GCC_DEBUG_FLAGS) $(GCC_OVERFLOW_FLAGS)"
-mkdir /tmp/,tzpublic
-for i in $(TDATA) ; do zic -v -d /tmp/,tzpublic $$i 2>&1 | grep -v "starting year" ; done
for i in $(TDATA) ; do zic -d /tmp/,tzpublic $$i || exit; done
Index: src/lib/libc/time/localtime.c
diff -u src/lib/libc/time/localtime.c:1.51 src/lib/libc/time/localtime.c:1.52
--- src/lib/libc/time/localtime.c:1.51 Wed Jan 5 21:41:34 2011
+++ src/lib/libc/time/localtime.c Fri Jan 14 18:35:07 2011
@@ -1,4 +1,4 @@
-/* $NetBSD: localtime.c,v 1.51 2011/01/06 02:41:34 christos Exp $ */
+/* $NetBSD: localtime.c,v 1.52 2011/01/14 23:35:07 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 1.51 2011/01/06 02:41:34 christos Exp $");
+__RCSID("$NetBSD: localtime.c,v 1.52 2011/01/14 23:35:07 christos Exp $");
#endif
#endif /* LIBC_SCCS and not lint */
@@ -1704,8 +1704,10 @@
int number0;
number0 = *number;
+ if (delta < 0 ? number0 < delta - INT_MIN : 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 < delta - LONG_MIN : LONG_MAX - delta < number0)
+ return 1;
*number += delta;
- return (*number < number0) != (delta < 0);
+ return 0;
}
static int
Index: src/lib/libc/time/zdump.c
diff -u src/lib/libc/time/zdump.c:1.17 src/lib/libc/time/zdump.c:1.18
--- src/lib/libc/time/zdump.c:1.17 Thu Dec 31 17:49:16 2009
+++ src/lib/libc/time/zdump.c Fri Jan 14 18:35:07 2011
@@ -1,4 +1,4 @@
-/* $NetBSD: zdump.c,v 1.17 2009/12/31 22:49:16 mlelstv Exp $ */
+/* $NetBSD: zdump.c,v 1.18 2011/01/14 23:35:07 christos Exp $ */
/*
** This file is in the public domain, so clarified as of
** 2009-05-17 by Arthur David Olson.
@@ -7,7 +7,7 @@
#include <sys/cdefs.h>
#ifndef lint
#ifndef NOID
-__RCSID("$NetBSD: zdump.c,v 1.17 2009/12/31 22:49:16 mlelstv Exp $");
+__RCSID("$NetBSD: zdump.c,v 1.18 2011/01/14 23:35:07 christos Exp $");
#endif /* !defined NOID */
#endif /* !defined lint */
@@ -26,6 +26,7 @@
#include "stdlib.h" /* for exit, malloc, atoi */
#include <err.h>
#include "float.h" /* for FLT_MAX and DBL_MAX */
+#include "limits.h" /* for INT_MAX, LONG_MAX, etc. */
#include "ctype.h" /* for isalpha et al. */
#ifndef isascii
#define isascii(x) 1
@@ -431,21 +432,25 @@
}
} else if (0 > (time_t) -1) {
/*
- ** time_t is signed. Assume overflow wraps around.
+ ** time_t is signed.
*/
- time_t t = 0;
- time_t t1 = 1;
-
- while (t < t1) {
- t = t1;
- t1 = 2 * t1 + 1;
+ if (sizeof (time_t) == sizeof (int)) {
+ absolute_min_time = INT_MIN;
+ absolute_max_time = INT_MAX;
+ } else if (sizeof (time_t) == sizeof (long)) {
+ absolute_min_time = LONG_MIN;
+ absolute_max_time = LONG_MAX;
+#if defined LLONG_MIN && defined LLONG_MAX
+ } else if (sizeof (time_t) == sizeof (long long)) {
+ absolute_min_time = LLONG_MIN;
+ absolute_max_time = LLONG_MAX;
+#endif
+ } else {
+ (void) fprintf(stderr,
+_("%s: use of -v on system with signed time_t whose extrema are unknown\n"),
+ progname);
+ exit(EXIT_FAILURE);
}
-
- absolute_max_time = t;
- t = -t;
- absolute_min_time = t - 1;
- if (t < absolute_min_time)
- absolute_min_time = t;
} else {
/*
** time_t is unsigned.
Index: src/lib/libc/time/zic.c
diff -u src/lib/libc/time/zic.c:1.26 src/lib/libc/time/zic.c:1.27
--- src/lib/libc/time/zic.c:1.26 Sat Jan 2 05:42:49 2010
+++ src/lib/libc/time/zic.c Fri Jan 14 18:35:07 2011
@@ -1,4 +1,4 @@
-/* $NetBSD: zic.c,v 1.26 2010/01/02 10:42:49 tsutsui Exp $ */
+/* $NetBSD: zic.c,v 1.27 2011/01/14 23:35:07 christos Exp $ */
/*
** This file is in the public domain, so clarified as of
** 2006-07-17 by Arthur David Olson.
@@ -10,7 +10,7 @@
#include <sys/cdefs.h>
#ifndef lint
-__RCSID("$NetBSD: zic.c,v 1.26 2010/01/02 10:42:49 tsutsui Exp $");
+__RCSID("$NetBSD: zic.c,v 1.27 2011/01/14 23:35:07 christos Exp $");
#endif /* !defined lint */
static char elsieid[] = "@(#)zic.c 8.20";
@@ -2496,14 +2496,11 @@
const long t1;
const long t2;
{
- register long t;
-
- t = t1 + t2;
- if ((t2 > 0 && t <= t1) || (t2 < 0 && t >= t1)) {
+ if (t2 < 0 ? t1 < t2 - LONG_MIN : LONG_MAX - t2 < t1) {
error(_("time overflow"));
exit(EXIT_FAILURE);
}
- return t;
+ return t1 + t2;
}
static zic_t
@@ -2511,18 +2508,15 @@
const zic_t t1;
const long t2;
{
- register zic_t t;
-
if (t1 == max_time && t2 > 0)
return max_time;
if (t1 == min_time && t2 < 0)
return min_time;
- t = t1 + t2;
- if ((t2 > 0 && t <= t1) || (t2 < 0 && t >= t1)) {
+ if (t2 < 0 ? t1 < t2 - LONG_MIN : LONG_MAX - t2 < t1) {
error(_("time overflow"));
exit(EXIT_FAILURE);
}
- return t;
+ return t1 + t2;
}
/*
