changeset 7276:4be2c469b318

* config/srclist.txt: Temporarily comment out mktime.c until glibc bug 2821 is fixed. * lib/mktime.c (guess_time_tm): Fix bug where mktime returned the maximum time_t value rather than (time_t) -1. Problem originally reported by William Bardwell <http://sourceware.org/bugzilla/show_bug.cgi?id=2821>. * m4/mktime.m4 (AC_FUNC_MKTIME): Sync from Autoconf. Check for unistd.h too, since Autoconf doesn't assume POSIX. Also: 2006-09-08 Paul Eggert <eggert@cs.ucla.edu> Add year_2050_test to catch glibc bug 2821 <http://sourceware.org/bugzilla/show_bug.cgi?id=2821>. 2006-08-15 Paul Eggert <eggert@cs.ucla.edu> Prefer #ifdef to #if. 2006-04-02 Paul Eggert <eggert@cs.ucla.edu> Return from 'main' instead of calling 'exit'.
author Paul Eggert <eggert@cs.ucla.edu>
date Fri, 08 Sep 2006 22:48:25 +0000
parents 09d34e7dc0d8
children e6927185dbdf
files config/ChangeLog config/srclist.txt lib/ChangeLog lib/mktime.c m4/ChangeLog m4/mktime.m4
diffstat 6 files changed, 102 insertions(+), 41 deletions(-) [+]
line wrap: on
line diff
--- a/config/ChangeLog
+++ b/config/ChangeLog
@@ -1,3 +1,8 @@
+2006-09-08  Paul Eggert  <eggert@cs.ucla.edu>
+
+	* srclist.txt: Temporarily comment out mktime.c until glibc bug
+	2821 is fixed.
+
 2006-09-04  Karl Berry  <karl@gnu.org>
 
 	* srclist.txt (signed.m4, gettext.m4): changes not propagated
--- a/config/srclist.txt
+++ b/config/srclist.txt
@@ -1,4 +1,4 @@
-# $Id: srclist.txt,v 1.137 2006-09-04 12:45:56 karl Exp $
+# $Id: srclist.txt,v 1.138 2006-09-08 22:48:25 eggert Exp $
 # Files for which we are not the source.  See ./srclistvars.sh for the
 # variable definitions.
 
@@ -195,7 +195,8 @@
 $LIBCSRC/stdlib/strtoul.c		lib gpl
 $LIBCSRC/string/strtok_r.c		lib gpl
 $LIBCSRC/string/memmem.c		lib gpl
-$LIBCSRC/time/mktime.c			lib gpl
+# http://sourceware.org/bugzilla/show_bug.cgi?id=2821
+#$LIBCSRC/time/mktime.c			lib gpl
 
 #
 # http://sourceware.org/bugzilla/show_bug.cgi?id=1439
--- a/lib/ChangeLog
+++ b/lib/ChangeLog
@@ -1,5 +1,10 @@
 2006-09-08  Paul Eggert  <eggert@cs.ucla.edu>
 
+	* mktime.c (guess_time_tm): Fix bug where mktime
+	returned the maximum time_t value rather than (time_t) -1.
+	Problem originally reported by William Bardwell
+	<http://sourceware.org/bugzilla/show_bug.cgi?id=2821>.
+
 	* isapipe.h (HAVE_FIFO_PIPES) [!defined HAVE_FIFO_PIPES]:
 	Moved to here ...
 	* isapipe.c (HAVE_FIFO_PIPES) [!defined HAVE_FIFO_PIPES]:
--- a/lib/mktime.c
+++ b/lib/mktime.c
@@ -1,5 +1,5 @@
 /* Convert a `struct tm' to a time_t value.
-   Copyright (C) 1993-1999, 2002-2004, 2005 Free Software Foundation, Inc.
+   Copyright (C) 1993-1999, 2002-2004, 2005, 2006 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Paul Eggert (eggert@twinsun.com).
 
@@ -215,10 +215,11 @@
   /* Overflow occurred one way or another.  Return the nearest result
      that is actually in range, except don't report a zero difference
      if the actual difference is nonzero, as that would cause a false
-     match.  */
+     match; and don't oscillate between two values, as that would
+     confuse the spring-forward gap detector.  */
   return (*t < TIME_T_MIDPOINT
-	  ? TIME_T_MIN + (*t == TIME_T_MIN)
-	  : TIME_T_MAX - (*t == TIME_T_MAX));
+	  ? (*t <= TIME_T_MIN + 1 ? *t + 1 : TIME_T_MIN)
+	  : (TIME_T_MAX - 1 <= *t ? *t - 1 : TIME_T_MAX));
 }
 
 /* Use CONVERT to convert *T to a broken down time in *TP.
--- a/m4/ChangeLog
+++ b/m4/ChangeLog
@@ -1,3 +1,19 @@
+2006-09-08  Paul Eggert  <eggert@cs.ucla.edu>
+
+	* mktime.m4 (AC_FUNC_MKTIME): Sync from Autoconf.
+	Check for unistd.h too, since Autoconf doesn't assume POSIX.
+	Also:
+
+	2006-09-08  Paul Eggert  <eggert@cs.ucla.edu>
+	Add year_2050_test to catch glibc bug 2821
+	<http://sourceware.org/bugzilla/show_bug.cgi?id=2821>.
+
+	2006-08-15  Paul Eggert  <eggert@cs.ucla.edu>
+	Prefer #ifdef to #if.
+
+	2006-04-02  Paul Eggert  <eggert@cs.ucla.edu>
+	Return from 'main' instead of calling 'exit'.
+
 2006-09-08  Jim Meyering  <jim@meyering.net>
 
 	Avoid new build failure on FreeBSD 6.0.
--- a/m4/mktime.m4
+++ b/m4/mktime.m4
@@ -1,29 +1,29 @@
-#serial 7
-dnl Copyright (C) 2002, 2003, 2005 Free Software Foundation, Inc.
+#serial 8
+dnl Copyright (C) 2002, 2003, 2005, 2006 Free Software Foundation, Inc.
 dnl This file is free software; the Free Software Foundation
 dnl gives unlimited permission to copy and/or distribute it,
 dnl with or without modifications, as long as this notice is preserved.
 
 dnl From Jim Meyering.
 
-# Redefine AC_FUNC_MKTIME, to fix a bug in Autoconf 2.57 and earlier.
-# This redefinition can be removed once a new version of Autoconf comes out.
+# Redefine AC_FUNC_MKTIME, to fix a bug in Autoconf 2.60a and earlier.
+# This redefinition can be removed once a new version of Autoconf is assumed.
 # The redefinition is taken from
-# <http://savannah.gnu.org/cgi-bin/viewcvs/*checkout*/autoconf/autoconf/lib/autoconf/functions.m4?rev=1.78>.
+# <http://cvs.sv.gnu.org/viewcvs/*checkout*/autoconf/lib/autoconf/functions.m4?rev=1.108&root=autoconf>.
 # AC_FUNC_MKTIME
 # --------------
 AC_DEFUN([AC_FUNC_MKTIME],
 [AC_REQUIRE([AC_HEADER_TIME])dnl
-AC_CHECK_HEADERS_ONCE(sys/time.h)
+AC_CHECK_HEADERS_ONCE(sys/time.h unistd.h)
 AC_CHECK_FUNCS_ONCE(alarm)
 AC_CACHE_CHECK([for working mktime], ac_cv_func_working_mktime,
 [AC_RUN_IFELSE([AC_LANG_SOURCE(
 [[/* Test program from Paul Eggert and Tony Leneis.  */
-#if TIME_WITH_SYS_TIME
+#ifdef TIME_WITH_SYS_TIME
 # include <sys/time.h>
 # include <time.h>
 #else
-# if HAVE_SYS_TIME_H
+# ifdef HAVE_SYS_TIME_H
 #  include <sys/time.h>
 # else
 #  include <time.h>
@@ -31,9 +31,12 @@
 #endif
 
 #include <stdlib.h>
-#include <unistd.h>
 
-#if !HAVE_ALARM
+#ifdef HAVE_UNISTD_H
+# include <unistd.h>
+#endif
+
+#ifndef HAVE_ALARM
 # define alarm(X) /* empty */
 #endif
 
@@ -50,9 +53,9 @@
 };
 #define N_STRINGS (sizeof (tz_strings) / sizeof (tz_strings[0]))
 
-/* Fail if mktime fails to convert a date in the spring-forward gap.
+/* Return 0 if mktime fails to convert a date in the spring-forward gap.
    Based on a problem report from Andreas Jaeger.  */
-static void
+static int
 spring_forward_gap ()
 {
   /* glibc (up to about 1998-10-07) failed this test. */
@@ -71,29 +74,27 @@
   tm.tm_min = 0;
   tm.tm_sec = 0;
   tm.tm_isdst = -1;
-  if (mktime (&tm) == (time_t)-1)
-    exit (1);
+  return mktime (&tm) != (time_t) -1;
 }
 
-static void
+static int
 mktime_test1 (now)
      time_t now;
 {
   struct tm *lt;
-  if ((lt = localtime (&now)) && mktime (lt) != now)
-    exit (1);
+  return ! (lt = localtime (&now)) || mktime (lt) == now;
 }
 
-static void
+static int
 mktime_test (now)
      time_t now;
 {
-  mktime_test1 (now);
-  mktime_test1 ((time_t) (time_t_max - now));
-  mktime_test1 ((time_t) (time_t_min + now));
+  return (mktime_test1 (now)
+	  && mktime_test1 ((time_t) (time_t_max - now))
+	  && mktime_test1 ((time_t) (time_t_min + now)));
 }
 
-static void
+static int
 irix_6_4_bug ()
 {
   /* Based on code from Ariel Faigon.  */
@@ -106,11 +107,10 @@
   tm.tm_sec = 0;
   tm.tm_isdst = -1;
   mktime (&tm);
-  if (tm.tm_mon != 2 || tm.tm_mday != 31)
-    exit (1);
+  return tm.tm_mon == 2 && tm.tm_mday == 31;
 }
 
-static void
+static int
 bigtime_test (j)
      int j;
 {
@@ -132,8 +132,39 @@
 	     && lt->tm_wday == tm.tm_wday
 	     && ((lt->tm_isdst < 0 ? -1 : 0 < lt->tm_isdst)
 		  == (tm.tm_isdst < 0 ? -1 : 0 < tm.tm_isdst))))
-	exit (1);
+	return 0;
     }
+  return 1;
+}
+
+static int
+year_2050_test ()
+{
+  /* The correct answer for 2050-02-01 00:00:00 in Pacific time,
+     ignoring leap seconds.  */
+  unsigned long int answer = 2527315200UL;
+
+  struct tm tm;
+  time_t t;
+  tm.tm_year = 2050 - 1900;
+  tm.tm_mon = 2 - 1;
+  tm.tm_mday = 1;
+  tm.tm_hour = tm.tm_min = tm.tm_sec = 0;
+  tm.tm_isdst = -1;
+
+  /* Use the portable POSIX.1 specification "TZ=PST8PDT,M4.1.0,M10.5.0"
+     instead of "TZ=America/Vancouver" in order to detect the bug even
+     on systems that don't support the Olson extension, or don't have the
+     full zoneinfo tables installed.  */
+  putenv ("TZ=PST8PDT,M4.1.0,M10.5.0");
+
+  t = mktime (&tm);
+
+  /* Check that the result is either a failure, or close enough
+     to the correct answer that we can assume the discrepancy is
+     due to leap seconds.  */
+  return (t == (time_t) -1
+	  || (0 < t && answer - 120 <= t && t <= answer + 120));
 }
 
 int
@@ -160,18 +191,20 @@
 	putenv (tz_strings[i]);
 
       for (t = 0; t <= time_t_max - delta; t += delta)
-	mktime_test (t);
-      mktime_test ((time_t) 1);
-      mktime_test ((time_t) (60 * 60));
-      mktime_test ((time_t) (60 * 60 * 24));
+	if (! mktime_test (t))
+	  return 1;
+      if (! (mktime_test ((time_t) 1)
+	     && mktime_test ((time_t) (60 * 60))
+	     && mktime_test ((time_t) (60 * 60 * 24))))
+	return 1;
 
       for (j = 1; 0 < j; j *= 2)
-	bigtime_test (j);
-      bigtime_test (j - 1);
+	if (! bigtime_test (j))
+	  return 1;
+      if (! bigtime_test (j - 1))
+	return 1;
     }
-  irix_6_4_bug ();
-  spring_forward_gap ();
-  exit (0);
+  return ! (irix_6_4_bug () && spring_forward_gap () && year_2050_test ());
 }]])],
 	       [ac_cv_func_working_mktime=yes],
 	       [ac_cv_func_working_mktime=no],