This is the mail archive of the glibc-cvs@sourceware.org mailing list for the glibc project.


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]
Other format: [Raw text]

GNU C Library master sources branch master updated. glibc-2.28.9000-298-g5d8af15


This is an automated email from the git hooks/post-receive script. It was
generated because a ref change was pushed to the repository containing
the project "GNU C Library master sources".

The branch, master has been updated
       via  5d8af1566bd98aa9c2728f8f63f7ba43cfa84d09 (commit)
       via  86aece3bfbd44538ba4fdc947872c81d4c5e6e61 (commit)
       via  f6b3331bbae638d1bb50813fceb429d3b3dc0eb9 (commit)
       via  efbdddc381cfea5bfa9527e86fa3078257e5d91b (commit)
       via  6c90d759f613761de7ac435bbabcc373092cf8bc (commit)
       via  32c12f3f7ac9736d9ca2f0e074f1a3d02e973a35 (commit)
       via  de20b81a038fe1c2060ce28125eec3838de5bdc5 (commit)
      from  8c6c3fb0bceba87045eccadcfa50129ea95a6ebf (commit)

Those revisions listed above that are new to this repository have
not appeared on any other notification email; so we list those
revisions in full, below.

- Log -----------------------------------------------------------------
http://sourceware.org/git/gitweb.cgi?p=glibc.git;a=commitdiff;h=5d8af1566bd98aa9c2728f8f63f7ba43cfa84d09

commit 5d8af1566bd98aa9c2728f8f63f7ba43cfa84d09
Author: Paul Eggert <eggert@cs.ucla.edu>
Date:   Thu Nov 15 22:59:33 2018 +0100

    mktime: DEBUG_MKTIME cleanup
    
    The DEBUG_MKTIME code no longer works in glibc or in Gnulib.
    And itâ??s no longer needed now that glibc and Gnulib both have
    their own testing mechanisms for mktime.
    * time/mktime.c (DEBUG_MKTIME): Remove.  All uses removed.

diff --git a/ChangeLog b/ChangeLog
index f4b6d06..b24b6b0 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,11 @@
 2018-11-15  Paul Eggert  <eggert@cs.ucla.edu>
 
+	mktime: DEBUG_MKTIME cleanup
+	The DEBUG_MKTIME code no longer works in glibc or in Gnulib.
+	And itâ??s no longer needed now that glibc and Gnulib both have
+	their own testing mechanisms for mktime.
+	* time/mktime.c (DEBUG_MKTIME): Remove.  All uses removed.
+
 	mktime: fix non-EOVERFLOW errno handling
 	[BZ#23789]
 	mktime was not properly reporting failures when the underlying
diff --git a/time/mktime.c b/time/mktime.c
index dc83985..8faa9bc 100644
--- a/time/mktime.c
+++ b/time/mktime.c
@@ -17,12 +17,6 @@
    License along with the GNU C Library; if not, see
    <https://www.gnu.org/licenses/>.  */
 
-/* Define this to 1 to have a standalone program to test this implementation of
-   mktime.  */
-#ifndef DEBUG_MKTIME
-# define DEBUG_MKTIME 0
-#endif
-
 /* The following macros influence what gets defined when this file is compiled:
 
    Macro/expression            Which gnulib module    This compilation unit
@@ -34,11 +28,9 @@
    || NEED_MKTIME_WINDOWS
 
    NEED_MKTIME_INTERNAL        mktime-internal        mktime_internal
-
-   DEBUG_MKTIME                (defined manually)     my_mktime, main
  */
 
-#if !defined _LIBC && !DEBUG_MKTIME
+#ifndef _LIBC
 # include <libc-config.h>
 #endif
 
@@ -60,13 +52,6 @@
 #include <intprops.h>
 #include <verify.h>
 
-#if DEBUG_MKTIME
-# include <stdio.h>
-/* Make it work even if the system's libc has its own mktime routine.  */
-# undef mktime
-# define mktime my_mktime
-#endif /* DEBUG_MKTIME */
-
 #ifndef NEED_MKTIME_INTERNAL
 # define NEED_MKTIME_INTERNAL 0
 #endif
@@ -74,7 +59,7 @@
 # define NEED_MKTIME_WINDOWS 0
 #endif
 #ifndef NEED_MKTIME_WORKING
-# define NEED_MKTIME_WORKING DEBUG_MKTIME
+# define NEED_MKTIME_WORKING 0
 #endif
 
 #include "mktime-internal.h"
@@ -562,146 +547,3 @@ weak_alias (mktime, timelocal)
 libc_hidden_def (mktime)
 libc_hidden_weak (timelocal)
 #endif
-
-#if DEBUG_MKTIME
-
-static int
-not_equal_tm (const struct tm *a, const struct tm *b)
-{
-  return ((a->tm_sec ^ b->tm_sec)
-	  | (a->tm_min ^ b->tm_min)
-	  | (a->tm_hour ^ b->tm_hour)
-	  | (a->tm_mday ^ b->tm_mday)
-	  | (a->tm_mon ^ b->tm_mon)
-	  | (a->tm_year ^ b->tm_year)
-	  | (a->tm_yday ^ b->tm_yday)
-	  | isdst_differ (a->tm_isdst, b->tm_isdst));
-}
-
-static void
-print_tm (const struct tm *tp)
-{
-  if (tp)
-    printf ("%04d-%02d-%02d %02d:%02d:%02d yday %03d wday %d isdst %d",
-	    tp->tm_year + TM_YEAR_BASE, tp->tm_mon + 1, tp->tm_mday,
-	    tp->tm_hour, tp->tm_min, tp->tm_sec,
-	    tp->tm_yday, tp->tm_wday, tp->tm_isdst);
-  else
-    printf ("0");
-}
-
-static int
-check_result (time_t tk, struct tm tmk, time_t tl, const struct tm *lt)
-{
-  if (tk != tl || !lt || not_equal_tm (&tmk, lt))
-    {
-      printf ("mktime (");
-      print_tm (lt);
-      printf (")\nyields (");
-      print_tm (&tmk);
-      printf (") == %ld, should be %ld\n", (long int) tk, (long int) tl);
-      return 1;
-    }
-
-  return 0;
-}
-
-int
-main (int argc, char **argv)
-{
-  int status = 0;
-  struct tm tm, tmk, tml;
-  struct tm *lt;
-  time_t tk, tl, tl1;
-  char trailer;
-
-  /* Sanity check, plus call tzset.  */
-  tl = 0;
-  if (! localtime (&tl))
-    {
-      printf ("localtime (0) fails\n");
-      status = 1;
-    }
-
-  if ((argc == 3 || argc == 4)
-      && (sscanf (argv[1], "%d-%d-%d%c",
-		  &tm.tm_year, &tm.tm_mon, &tm.tm_mday, &trailer)
-	  == 3)
-      && (sscanf (argv[2], "%d:%d:%d%c",
-		  &tm.tm_hour, &tm.tm_min, &tm.tm_sec, &trailer)
-	  == 3))
-    {
-      tm.tm_year -= TM_YEAR_BASE;
-      tm.tm_mon--;
-      tm.tm_isdst = argc == 3 ? -1 : atoi (argv[3]);
-      tmk = tm;
-      tl = mktime (&tmk);
-      lt = localtime_r (&tl, &tml);
-      printf ("mktime returns %ld == ", (long int) tl);
-      print_tm (&tmk);
-      printf ("\n");
-      status = check_result (tl, tmk, tl, lt);
-    }
-  else if (argc == 4 || (argc == 5 && strcmp (argv[4], "-") == 0))
-    {
-      time_t from = atol (argv[1]);
-      time_t by = atol (argv[2]);
-      time_t to = atol (argv[3]);
-
-      if (argc == 4)
-	for (tl = from; by < 0 ? to <= tl : tl <= to; tl = tl1)
-	  {
-	    lt = localtime_r (&tl, &tml);
-	    if (lt)
-	      {
-		tmk = tml;
-		tk = mktime (&tmk);
-		status |= check_result (tk, tmk, tl, &tml);
-	      }
-	    else
-	      {
-		printf ("localtime_r (%ld) yields 0\n", (long int) tl);
-		status = 1;
-	      }
-	    tl1 = tl + by;
-	    if ((tl1 < tl) != (by < 0))
-	      break;
-	  }
-      else
-	for (tl = from; by < 0 ? to <= tl : tl <= to; tl = tl1)
-	  {
-	    /* Null benchmark.  */
-	    lt = localtime_r (&tl, &tml);
-	    if (lt)
-	      {
-		tmk = tml;
-		tk = tl;
-		status |= check_result (tk, tmk, tl, &tml);
-	      }
-	    else
-	      {
-		printf ("localtime_r (%ld) yields 0\n", (long int) tl);
-		status = 1;
-	      }
-	    tl1 = tl + by;
-	    if ((tl1 < tl) != (by < 0))
-	      break;
-	  }
-    }
-  else
-    printf ("Usage:\
-\t%s YYYY-MM-DD HH:MM:SS [ISDST] # Test given time.\n\
-\t%s FROM BY TO # Test values FROM, FROM+BY, ..., TO.\n\
-\t%s FROM BY TO - # Do not test those values (for benchmark).\n",
-	    argv[0], argv[0], argv[0]);
-
-  return status;
-}
-
-#endif /* DEBUG_MKTIME */
-
-/*
-Local Variables:
-compile-command: "gcc -DDEBUG_MKTIME -I. -Wall -W -O2 -g mktime.c -o mktime"
-End:
-*/

http://sourceware.org/git/gitweb.cgi?p=glibc.git;a=commitdiff;h=86aece3bfbd44538ba4fdc947872c81d4c5e6e61

commit 86aece3bfbd44538ba4fdc947872c81d4c5e6e61
Author: Paul Eggert <eggert@cs.ucla.edu>
Date:   Thu Nov 15 22:59:33 2018 +0100

    mktime: fix non-EOVERFLOW errno handling
    
    [BZ#23789]
    mktime was not properly reporting failures when the underlying
    localtime_r fails with errno != EOVERFLOW; it incorrectly treated
    them like EOVERFLOW failures, and set errno to EOVERFLOW.
    The problem could happen on non-glibc platforms, with Gnulib.
    * time/mktime.c (guess_time_tm): Remove, replacing with ...
    (tm_diff): ... this simpler function, which does not change errno.
    All callers changed to deal with errno themselves.
    (ranged_convert, __mktime_internal): Return failure immediately if
    the underlying function reports any failure other than EOVERFLOW.
    (__mktime_internal): Set errno to EOVERFLOW if the spring-forward
    gap code fails.

diff --git a/ChangeLog b/ChangeLog
index d503a3e..f4b6d06 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,19 @@
 2018-11-15  Paul Eggert  <eggert@cs.ucla.edu>
 
+	mktime: fix non-EOVERFLOW errno handling
+	[BZ#23789]
+	mktime was not properly reporting failures when the underlying
+	localtime_r fails with errno != EOVERFLOW; it incorrectly treated
+	them like EOVERFLOW failures, and set errno to EOVERFLOW.
+	The problem could happen on non-glibc platforms, with Gnulib.
+	* time/mktime.c (guess_time_tm): Remove, replacing with ...
+	(tm_diff): ... this simpler function, which does not change errno.
+	All callers changed to deal with errno themselves.
+	(ranged_convert, __mktime_internal): Return failure immediately if
+	the underlying function reports any failure other than EOVERFLOW.
+	(__mktime_internal): Set errno to EOVERFLOW if the spring-forward
+	gap code fails.
+
 	mktime: fix bug with Y2038 DST transition
 	[BZ#23789]
 	* time/mktime.c (ranged_convert): On 32-bit platforms, donâ??t
diff --git a/time/mktime.c b/time/mktime.c
index 6d5b8cf..dc83985 100644
--- a/time/mktime.c
+++ b/time/mktime.c
@@ -250,45 +250,25 @@ long_int_avg (long_int a, long_int b)
   return shr (a, 1) + shr (b, 1) + ((a | b) & 1);
 }
 
-/* Return a time_t value corresponding to (YEAR-YDAY HOUR:MIN:SEC),
-   assuming that T corresponds to *TP and that no clock adjustments
-   occurred between *TP and the desired time.
-   Although T and the returned value are of type long_int,
-   they represent time_t values and must be in time_t range.
-   If TP is null, return a value not equal to T; this avoids false matches.
+/* Return a long_int value corresponding to (YEAR-YDAY HOUR:MIN:SEC)
+   minus *TP seconds, assuming no clock adjustments occurred between
+   the two timestamps.
+
    YEAR and YDAY must not be so large that multiplying them by three times the
    number of seconds in a year (or day, respectively) would overflow long_int.
-   If TP is non-null and the returned value would be out of range, set
-   errno to EOVERFLOW and yield a minimal or maximal in-range value
-   that is not equal to T.  */
+   *TP should be in the usual range.  */
 static long_int
-guess_time_tm (long_int year, long_int yday, int hour, int min, int sec,
-	       long_int t, const struct tm *tp)
+tm_diff (long_int year, long_int yday, int hour, int min, int sec,
+	 struct tm const *tp)
 {
-  if (tp)
-    {
-      long_int result;
-      long_int d = ydhms_diff (year, yday, hour, min, sec,
-			       tp->tm_year, tp->tm_yday,
-			       tp->tm_hour, tp->tm_min, tp->tm_sec);
-      if (! INT_ADD_WRAPV (t, d, &result))
-	return result;
-      __set_errno (EOVERFLOW);
-    }
-
-  /* An error occurred, probably overflow.  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; and don't oscillate between two values, as that would
-     confuse the spring-forward gap detector.  */
-  return (t < long_int_avg (mktime_min, mktime_max)
-	  ? (t <= mktime_min + 1 ? t + 1 : mktime_min)
-	  : (mktime_max - 1 <= t ? t - 1 : mktime_max));
+  return ydhms_diff (year, yday, hour, min, sec,
+		     tp->tm_year, tp->tm_yday,
+		     tp->tm_hour, tp->tm_min, tp->tm_sec);
 }
 
 /* Use CONVERT to convert T to a struct tm value in *TM.  T must be in
-   range for time_t.  Return TM if successful, NULL if T is out of
-   range for CONVERT.  */
+   range for time_t.  Return TM if successful, NULL (setting errno) on
+   failure.  */
 static struct tm *
 convert_time (struct tm *(*convert) (const time_t *, struct tm *),
 	      long_int t, struct tm *tm)
@@ -300,49 +280,48 @@ convert_time (struct tm *(*convert) (const time_t *, struct tm *),
 /* Use CONVERT to convert *T to a broken down time in *TP.
    If *T is out of range for conversion, adjust it so that
    it is the nearest in-range value and then convert that.
-   A value is in range if it fits in both time_t and long_int.  */
+   A value is in range if it fits in both time_t and long_int.
+   Return TP on success, NULL (setting errno) on failure.  */
 static struct tm *
 ranged_convert (struct tm *(*convert) (const time_t *, struct tm *),
 		long_int *t, struct tm *tp)
 {
-  struct tm *r;
-  if (*t < mktime_min)
-    *t = mktime_min;
-  else if (mktime_max < *t)
-    *t = mktime_max;
-  r = convert_time (convert, *t, tp);
-
-  if (!r && *t)
+  long_int t1 = (*t < mktime_min ? mktime_min
+		 : *t <= mktime_max ? *t : mktime_max);
+  struct tm *r = convert_time (convert, t1, tp);
+  if (r)
     {
-      long_int bad = *t;
-      long_int ok = 0;
-
-      /* BAD is a known unconvertible value, and OK is a known good one.
-	 Use binary search to narrow the range between BAD and OK until
-	 they differ by 1.  */
-      while (true)
-	{
-	  long_int mid = long_int_avg (ok, bad);
-	  if (mid == ok || mid == bad)
-	    break;
-	  r = convert_time (convert, mid, tp);
-	  if (r)
-	    ok = mid;
-	  else
-	    bad = mid;
-	}
+      *t = t1;
+      return r;
+    }
+  if (errno != EOVERFLOW)
+    return NULL;
 
-      *t = ok;
+  long_int bad = t1;
+  long_int ok = 0;
+  struct tm oktm; oktm.tm_sec = -1;
 
-      if (!r && ok)
-	{
-	  /* The last conversion attempt failed;
-	     revert to the most recent successful attempt.  */
-	  r = convert_time (convert, ok, tp);
-	}
+  /* BAD is a known out-of-range value, and OK is a known in-range one.
+     Use binary search to narrow the range between BAD and OK until
+     they differ by 1.  */
+  while (true)
+    {
+      long_int mid = long_int_avg (ok, bad);
+      if (mid == ok || mid == bad)
+	break;
+      if (convert_time (convert, mid, tp))
+	ok = mid, oktm = *tp;
+      else if (errno != EOVERFLOW)
+	return NULL;
+      else
+	bad = mid;
     }
 
-  return r;
+  if (oktm.tm_sec < 0)
+    return NULL;
+  *t = ok;
+  *tp = oktm;
+  return tp;
 }
 
 
@@ -359,7 +338,6 @@ __mktime_internal (struct tm *tp,
 		   struct tm *(*convert) (const time_t *, struct tm *),
 		   mktime_offset_t *offset)
 {
-  long_int t, gt, t0, t1, t2;
   struct tm tm;
 
   /* The maximum number of probes (calls to CONVERT) should be enough
@@ -379,7 +357,7 @@ __mktime_internal (struct tm *tp,
   int isdst = tp->tm_isdst;
 
   /* 1 if the previous probe was DST.  */
-  int dst2;
+  int dst2 = 0;
 
   /* Ensure that mon is in range, and set year accordingly.  */
   int mon_remainder = mon % 12;
@@ -418,36 +396,46 @@ __mktime_internal (struct tm *tp,
      time.  */
 
   INT_SUBTRACT_WRAPV (0, off, &negative_offset_guess);
-  t0 = ydhms_diff (year, yday, hour, min, sec,
-		   EPOCH_YEAR - TM_YEAR_BASE, 0, 0, 0, negative_offset_guess);
+  long_int t0 = ydhms_diff (year, yday, hour, min, sec,
+			    EPOCH_YEAR - TM_YEAR_BASE, 0, 0, 0,
+			    negative_offset_guess);
+  long_int t = t0, t1 = t0, t2 = t0;
 
   /* Repeatedly use the error to improve the guess.  */
 
-  for (t = t1 = t2 = t0, dst2 = 0;
-       (gt = guess_time_tm (year, yday, hour, min, sec, t,
-			    ranged_convert (convert, &t, &tm)),
-	t != gt);
-       t1 = t2, t2 = t, t = gt, dst2 = tm.tm_isdst != 0)
-    if (t == t1 && t != t2
-	&& (tm.tm_isdst < 0
-	    || (isdst < 0
-		? dst2 <= (tm.tm_isdst != 0)
-		: (isdst != 0) != (tm.tm_isdst != 0))))
-      /* We can't possibly find a match, as we are oscillating
-	 between two values.  The requested time probably falls
-	 within a spring-forward gap of size GT - T.  Follow the common
-	 practice in this case, which is to return a time that is GT - T
-	 away from the requested time, preferring a time whose
-	 tm_isdst differs from the requested value.  (If no tm_isdst
-	 was requested and only one of the two values has a nonzero
-	 tm_isdst, prefer that value.)  In practice, this is more
-	 useful than returning -1.  */
-      goto offset_found;
-    else if (--remaining_probes == 0)
-      {
-	__set_errno (EOVERFLOW);
+  while (true)
+    {
+      if (! ranged_convert (convert, &t, &tm))
 	return -1;
-      }
+      long_int dt = tm_diff (year, yday, hour, min, sec, &tm);
+      if (dt == 0)
+	break;
+
+      if (t == t1 && t != t2
+	  && (tm.tm_isdst < 0
+	      || (isdst < 0
+		  ? dst2 <= (tm.tm_isdst != 0)
+		  : (isdst != 0) != (tm.tm_isdst != 0))))
+	/* We can't possibly find a match, as we are oscillating
+	   between two values.  The requested time probably falls
+	   within a spring-forward gap of size DT.  Follow the common
+	   practice in this case, which is to return a time that is DT
+	   away from the requested time, preferring a time whose
+	   tm_isdst differs from the requested value.  (If no tm_isdst
+	   was requested and only one of the two values has a nonzero
+	   tm_isdst, prefer that value.)  In practice, this is more
+	   useful than returning -1.  */
+	goto offset_found;
+
+      remaining_probes--;
+      if (remaining_probes == 0)
+	{
+	  __set_errno (EOVERFLOW);
+	  return -1;
+	}
+
+      t1 = t2, t2 = t, t += dt, dst2 = tm.tm_isdst != 0;
+    }
 
   /* We have a match.  Check whether tm.tm_isdst has the requested
      value, if any.  */
@@ -489,17 +477,30 @@ __mktime_internal (struct tm *tp,
 	    if (! INT_ADD_WRAPV (t, delta * direction, &ot))
 	      {
 		struct tm otm;
-		ranged_convert (convert, &ot, &otm);
+		if (! ranged_convert (convert, &ot, &otm))
+		  return -1;
 		if (! isdst_differ (isdst, otm.tm_isdst))
 		  {
 		    /* We found the desired tm_isdst.
 		       Extrapolate back to the desired time.  */
-		    t = guess_time_tm (year, yday, hour, min, sec, ot, &otm);
-		    ranged_convert (convert, &t, &tm);
-		    goto offset_found;
+		    long_int gt = ot + tm_diff (year, yday, hour, min, sec,
+						&otm);
+		    if (mktime_min <= gt && gt <= mktime_max)
+		      {
+			if (convert_time (convert, gt, &tm))
+			  {
+			    t = gt;
+			    goto offset_found;
+			  }
+			if (errno != EOVERFLOW)
+			  return -1;
+		      }
 		  }
 	      }
 	  }
+
+      __set_errno (EOVERFLOW);
+      return -1;
     }
 
  offset_found:

http://sourceware.org/git/gitweb.cgi?p=glibc.git;a=commitdiff;h=f6b3331bbae638d1bb50813fceb429d3b3dc0eb9

commit f6b3331bbae638d1bb50813fceb429d3b3dc0eb9
Author: Paul Eggert <eggert@cs.ucla.edu>
Date:   Thu Nov 15 22:59:33 2018 +0100

    mktime: fix bug with Y2038 DST transition
    
    [BZ#23789]
    * time/mktime.c (ranged_convert): On 32-bit platforms, donâ??t
    mishandle a DST transition that jumps over the Y2038 boundary.
    No such DST transitions are known so this is only a theoretical
    bug, but we might as well do things right.

diff --git a/ChangeLog b/ChangeLog
index 064d0a3..d503a3e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,12 @@
 2018-11-15  Paul Eggert  <eggert@cs.ucla.edu>
 
+	mktime: fix bug with Y2038 DST transition
+	[BZ#23789]
+	* time/mktime.c (ranged_convert): On 32-bit platforms, donâ??t
+	mishandle a DST transition that jumps over the Y2038 boundary.
+	No such DST transitions are known so this is only a theoretical
+	bug, but we might as well do things right.
+
 	mktime: make more room for overflow
 	[BZ#23789]
 	* time/mktime.c (long_int): Now 4⨯ int, not just 3⨯.
diff --git a/time/mktime.c b/time/mktime.c
index ffbb5ea..6d5b8cf 100644
--- a/time/mktime.c
+++ b/time/mktime.c
@@ -323,7 +323,7 @@ ranged_convert (struct tm *(*convert) (const time_t *, struct tm *),
       while (true)
 	{
 	  long_int mid = long_int_avg (ok, bad);
-	  if (mid != ok && mid != bad)
+	  if (mid == ok || mid == bad)
 	    break;
 	  r = convert_time (convert, mid, tp);
 	  if (r)
@@ -332,6 +332,8 @@ ranged_convert (struct tm *(*convert) (const time_t *, struct tm *),
 	    bad = mid;
 	}
 
+      *t = ok;
+
       if (!r && ok)
 	{
 	  /* The last conversion attempt failed;

http://sourceware.org/git/gitweb.cgi?p=glibc.git;a=commitdiff;h=efbdddc381cfea5bfa9527e86fa3078257e5d91b

commit efbdddc381cfea5bfa9527e86fa3078257e5d91b
Author: Paul Eggert <eggert@cs.ucla.edu>
Date:   Thu Nov 15 22:59:33 2018 +0100

    mktime: make more room for overflow
    
    [BZ#23789]
    * time/mktime.c (long_int): Now 4⨯ int, not just 3⨯.
    This is so that we can add tm_diff results to a previous guess,
    which will be useful in a later patch.

diff --git a/ChangeLog b/ChangeLog
index f70c3be..064d0a3 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,11 @@
 2018-11-15  Paul Eggert  <eggert@cs.ucla.edu>
 
+	mktime: make more room for overflow
+	[BZ#23789]
+	* time/mktime.c (long_int): Now 4⨯ int, not just 3⨯.
+	This is so that we can add tm_diff results to a previous guess,
+	which will be useful in a later patch.
+
 	mktime: simplify offset guess
 	[BZ#23789]
 	* time/mktime.c (__mktime_internal): Omit excess precision.
diff --git a/time/mktime.c b/time/mktime.c
index 0f905eb..ffbb5ea 100644
--- a/time/mktime.c
+++ b/time/mktime.c
@@ -120,11 +120,12 @@ my_tzset (void)
 #if defined _LIBC || NEED_MKTIME_WORKING || NEED_MKTIME_INTERNAL
 
 /* A signed type that can represent an integer number of years
-   multiplied by three times the number of seconds in a year.  It is
+   multiplied by four times the number of seconds in a year.  It is
    needed when converting a tm_year value times the number of seconds
-   in a year.  The factor of three comes because these products need
+   in a year.  The factor of four comes because these products need
    to be subtracted from each other, and sometimes with an offset
-   added to them, without worrying about overflow.
+   added to them, and then with another timestamp added, without
+   worrying about overflow.
 
    Much of the code uses long_int to represent time_t values, to
    lessen the hassle of dealing with platforms where time_t is
@@ -132,12 +133,12 @@ my_tzset (void)
    time_t values that mktime can generate even on platforms where
    time_t is excessively wide.  */
 
-#if INT_MAX <= LONG_MAX / 3 / 366 / 24 / 60 / 60
+#if INT_MAX <= LONG_MAX / 4 / 366 / 24 / 60 / 60
 typedef long int long_int;
 #else
 typedef long long int long_int;
 #endif
-verify (INT_MAX <= TYPE_MAXIMUM (long_int) / 3 / 366 / 24 / 60 / 60);
+verify (INT_MAX <= TYPE_MAXIMUM (long_int) / 4 / 366 / 24 / 60 / 60);
 
 /* Shift A right by B bits portably, by dividing A by 2**B and
    truncating towards minus infinity.  B should be in the range 0 <= B
@@ -211,9 +212,10 @@ isdst_differ (int a, int b)
    were not adjusted between the timestamps.
 
    The YEAR values uses the same numbering as TP->tm_year.  Values
-   need not be in the usual range.  However, YEAR1 must not overflow
-   when multiplied by three times the number of seconds in a year, and
-   likewise for YDAY1 and three times the number of seconds in a day.  */
+   need not be in the usual range.  However, YEAR1 - YEAR0 must not
+   overflow even when multiplied by three times the number of seconds
+   in a year, and likewise for YDAY1 - YDAY0 and three times the
+   number of seconds in a day.  */
 
 static long_int
 ydhms_diff (long_int year1, long_int yday1, int hour1, int min1, int sec1,
@@ -403,7 +405,7 @@ __mktime_internal (struct tm *tp,
   if (LEAP_SECONDS_POSSIBLE)
     {
       /* Handle out-of-range seconds specially,
-	 since ydhms_tm_diff assumes every minute has 60 seconds.  */
+	 since ydhms_diff assumes every minute has 60 seconds.  */
       if (sec < 0)
 	sec = 0;
       if (59 < sec)

http://sourceware.org/git/gitweb.cgi?p=glibc.git;a=commitdiff;h=6c90d759f613761de7ac435bbabcc373092cf8bc

commit 6c90d759f613761de7ac435bbabcc373092cf8bc
Author: Paul Eggert <eggert@cs.ucla.edu>
Date:   Thu Nov 15 22:59:33 2018 +0100

    mktime: simplify offset guess
    
    [BZ#23789]
    * time/mktime.c (__mktime_internal): Omit excess precision.

diff --git a/ChangeLog b/ChangeLog
index 6f88de1..f70c3be 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,9 @@
 2018-11-15  Paul Eggert  <eggert@cs.ucla.edu>
 
+	mktime: simplify offset guess
+	[BZ#23789]
+	* time/mktime.c (__mktime_internal): Omit excess precision.
+
 	mktime: new test for mktime failure
 	[BZ#23789]
 	Based on a test suggested by Albert Aribaud in:
diff --git a/time/mktime.c b/time/mktime.c
index 106b4ea..0f905eb 100644
--- a/time/mktime.c
+++ b/time/mktime.c
@@ -355,7 +355,7 @@ __mktime_internal (struct tm *tp,
 		   struct tm *(*convert) (const time_t *, struct tm *),
 		   mktime_offset_t *offset)
 {
-  long_int t, gt, t0, t1, t2, dt;
+  long_int t, gt, t0, t1, t2;
   struct tm tm;
 
   /* The maximum number of probes (calls to CONVERT) should be enough
@@ -502,8 +502,8 @@ __mktime_internal (struct tm *tp,
   /* Set *OFFSET to the low-order bits of T - T0 - NEGATIVE_OFFSET_GUESS.
      This is just a heuristic to speed up the next mktime call, and
      correctness is unaffected if integer overflow occurs here.  */
-  INT_SUBTRACT_WRAPV (t, t0, &dt);
-  INT_SUBTRACT_WRAPV (dt, negative_offset_guess, offset);
+  INT_SUBTRACT_WRAPV (t, t0, offset);
+  INT_SUBTRACT_WRAPV (*offset, negative_offset_guess, offset);
 
   if (LEAP_SECONDS_POSSIBLE && sec_requested != tm.tm_sec)
     {

http://sourceware.org/git/gitweb.cgi?p=glibc.git;a=commitdiff;h=32c12f3f7ac9736d9ca2f0e074f1a3d02e973a35

commit 32c12f3f7ac9736d9ca2f0e074f1a3d02e973a35
Author: Paul Eggert <eggert@cs.ucla.edu>
Date:   Thu Nov 15 22:59:33 2018 +0100

    mktime: new test for mktime failure
    
    [BZ#23789]
    Based on a test suggested by Albert Aribaud in:
    https://www.sourceware.org/ml/libc-alpha/2018-10/msg00662.html
    * time/Makefile (tests): Add bug-mktime4.
    * time/bug-mktime4.c: New file.

diff --git a/ChangeLog b/ChangeLog
index b0c602e..6f88de1 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,12 @@
 2018-11-15  Paul Eggert  <eggert@cs.ucla.edu>
 
+	mktime: new test for mktime failure
+	[BZ#23789]
+	Based on a test suggested by Albert Aribaud in:
+	https://www.sourceware.org/ml/libc-alpha/2018-10/msg00662.html
+	* time/Makefile (tests): Add bug-mktime4.
+	* time/bug-mktime4.c: New file.
+
 	mktime: fix EOVERFLOW bug
 	[BZ#23789]
 	* time/mktime.c [!_LIBC && !DEBUG_MKTIME]:
diff --git a/time/Makefile b/time/Makefile
index ec3e39d..743bd99 100644
--- a/time/Makefile
+++ b/time/Makefile
@@ -43,7 +43,7 @@ tests	:= test_time clocktest tst-posixtz tst-strptime tst_wcsftime \
 	   tst-getdate tst-mktime tst-mktime2 tst-ftime_l tst-strftime \
 	   tst-mktime3 tst-strptime2 bug-asctime bug-asctime_r bug-mktime1 \
 	   tst-strptime3 bug-getdate1 tst-strptime-whitespace tst-ftime \
-	   tst-tzname tst-y2039
+	   tst-tzname tst-y2039 bug-mktime4
 
 include ../Rules
 
diff --git a/time/bug-mktime4.c b/time/bug-mktime4.c
new file mode 100644
index 0000000..9c076eb
--- /dev/null
+++ b/time/bug-mktime4.c
@@ -0,0 +1,92 @@
+#include <time.h>
+#include <errno.h>
+#include <limits.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <string.h>
+
+static bool
+equal_tm (struct tm const *t, struct tm const *u)
+{
+  return (t->tm_sec == u->tm_sec && t->tm_min == u->tm_min
+	  && t->tm_hour == u->tm_hour && t->tm_mday == u->tm_mday
+	  && t->tm_mon == u->tm_mon && t->tm_year == u->tm_year
+	  && t->tm_wday == u->tm_wday && t->tm_yday == u->tm_yday
+	  && t->tm_isdst == u->tm_isdst && t->tm_gmtoff == u->tm_gmtoff
+	  && t->tm_zone == u->tm_zone);
+}
+
+static int
+do_test (void)
+{
+  /* Calculate minimum time_t value.  This would be simpler with C11,
+     which has _Generic, but we cannot assume C11.  It would also
+     be simpler with intprops.h, which has TYPE_MINIMUM, but it's
+     better not to use glibc internals.  */
+  time_t time_t_min = -1;
+  time_t_min = (0 < time_t_min ? 0
+		: sizeof time_t_min == sizeof (long int) ? LONG_MIN
+		: sizeof time_t_min == sizeof (long long int) ? LLONG_MIN
+		: 1);
+  if (time_t_min == 1)
+    {
+      printf ("unknown time type\n");
+      return 1;
+    }
+  time_t ymin = time_t_min / 60 / 60 / 24 / 366;
+  bool mktime_should_fail = ymin == 0 || INT_MIN + 1900 < ymin + 1970;
+
+  struct tm tm0 = { .tm_year = INT_MIN, .tm_mday = 1, .tm_wday = -1 };
+  struct tm tm = tm0;
+  errno = 0;
+  time_t t = mktime (&tm);
+  long long int llt = t;
+  bool mktime_failed = tm.tm_wday == tm0.tm_wday;
+
+  if (mktime_failed)
+    {
+      if (! mktime_should_fail)
+	{
+	  printf ("mktime failed but should have succeeded\n");
+	  return 1;
+	}
+      if (errno == 0)
+	{
+	  printf ("mktime failed without setting errno");
+	  return 1;
+	}
+      if (t != (time_t) -1)
+	{
+	  printf ("mktime returned %lld but did not set tm_wday\n", llt);
+	  return 1;
+	}
+      if (! equal_tm (&tm, &tm0))
+	{
+	  printf ("mktime (P) failed but modified *P\n");
+	  return 1;
+	}
+    }
+  else
+    {
+      if (mktime_should_fail)
+	{
+	  printf ("mktime succeeded but should have failed\n");
+	  return 1;
+	}
+      struct tm *lt = localtime (&t);
+      if (lt == NULL)
+	{
+	  printf ("mktime returned a value rejected by localtime\n");
+	  return 1;
+	}
+      if (! equal_tm (lt, &tm))
+	{
+	  printf ("mktime result does not match localtime result\n");
+	  return 1;
+	}
+    }
+  return 0;
+}
+
+#define TIMEOUT 1000
+#include "support/test-driver.c"

http://sourceware.org/git/gitweb.cgi?p=glibc.git;a=commitdiff;h=de20b81a038fe1c2060ce28125eec3838de5bdc5

commit de20b81a038fe1c2060ce28125eec3838de5bdc5
Author: Paul Eggert <eggert@cs.ucla.edu>
Date:   Thu Nov 15 22:59:33 2018 +0100

    mktime: fix EOVERFLOW bug
    
    [BZ#23789]
    * time/mktime.c [!_LIBC && !DEBUG_MKTIME]:
    Include libc-config.h, not config.h, for __set_errno.
    (guess_time_tm, __mktime_internal): Set errno to EOVERFLOW on overflow.

diff --git a/ChangeLog b/ChangeLog
index 149f991..b0c602e 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,11 @@
+2018-11-15  Paul Eggert  <eggert@cs.ucla.edu>
+
+	mktime: fix EOVERFLOW bug
+	[BZ#23789]
+	* time/mktime.c [!_LIBC && !DEBUG_MKTIME]:
+	Include libc-config.h, not config.h, for __set_errno.
+	(guess_time_tm, __mktime_internal): Set errno to EOVERFLOW on overflow.
+
 2018-11-14  Samuel Thibault  <samuel.thibault@ens-lyon.org>
 
 	* sysdeps/mach/hurd/dl-sysdep.c (check_no_hidden): Use
diff --git a/time/mktime.c b/time/mktime.c
index 00f0dec..106b4ea 100644
--- a/time/mktime.c
+++ b/time/mktime.c
@@ -39,7 +39,7 @@
  */
 
 #if !defined _LIBC && !DEBUG_MKTIME
-# include <config.h>
+# include <libc-config.h>
 #endif
 
 /* Assume that leap seconds are possible, unless told otherwise.
@@ -51,6 +51,7 @@
 
 #include <time.h>
 
+#include <errno.h>
 #include <limits.h>
 #include <stdbool.h>
 #include <stdlib.h>
@@ -255,8 +256,9 @@ long_int_avg (long_int a, long_int b)
    If TP is null, return a value not equal to T; this avoids false matches.
    YEAR and YDAY must not be so large that multiplying them by three times the
    number of seconds in a year (or day, respectively) would overflow long_int.
-   If the returned value would be out of range, yield the minimal or
-   maximal in-range value, except do not yield a value equal to T.  */
+   If TP is non-null and the returned value would be out of range, set
+   errno to EOVERFLOW and yield a minimal or maximal in-range value
+   that is not equal to T.  */
 static long_int
 guess_time_tm (long_int year, long_int yday, int hour, int min, int sec,
 	       long_int t, const struct tm *tp)
@@ -269,9 +271,10 @@ guess_time_tm (long_int year, long_int yday, int hour, int min, int sec,
 			       tp->tm_hour, tp->tm_min, tp->tm_sec);
       if (! INT_ADD_WRAPV (t, d, &result))
 	return result;
+      __set_errno (EOVERFLOW);
     }
 
-  /* Overflow occurred one way or another.  Return the nearest result
+  /* An error occurred, probably overflow.  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; and don't oscillate between two values, as that would
@@ -344,6 +347,8 @@ ranged_convert (struct tm *(*convert) (const time_t *, struct tm *),
    Use *OFFSET to keep track of a guess at the offset of the result,
    compared to what the result would be for UTC without leap seconds.
    If *OFFSET's guess is correct, only one CONVERT call is needed.
+   If successful, set *TP to the canonicalized struct tm;
+   otherwise leave *TP alone, return ((time_t) -1) and set errno.
    This function is external because it is used also by timegm.c.  */
 time_t
 __mktime_internal (struct tm *tp,
@@ -435,7 +440,10 @@ __mktime_internal (struct tm *tp,
 	 useful than returning -1.  */
       goto offset_found;
     else if (--remaining_probes == 0)
-      return -1;
+      {
+	__set_errno (EOVERFLOW);
+	return -1;
+      }
 
   /* We have a match.  Check whether tm.tm_isdst has the requested
      value, if any.  */
@@ -505,8 +513,12 @@ __mktime_internal (struct tm *tp,
       sec_adjustment -= sec;
       sec_adjustment += sec_requested;
       if (INT_ADD_WRAPV (t, sec_adjustment, &t)
-	  || ! (mktime_min <= t && t <= mktime_max)
-	  || ! convert_time (convert, t, &tm))
+	  || ! (mktime_min <= t && t <= mktime_max))
+	{
+	  __set_errno (EOVERFLOW);
+	  return -1;
+	}
+      if (! convert_time (convert, t, &tm))
 	return -1;
     }
 

-----------------------------------------------------------------------

Summary of changes:
 ChangeLog          |   52 +++++++
 time/Makefile      |    2 +-
 time/bug-mktime4.c |   92 ++++++++++++
 time/mktime.c      |  391 +++++++++++++++++-----------------------------------
 4 files changed, 270 insertions(+), 267 deletions(-)
 create mode 100644 time/bug-mktime4.c


hooks/post-receive
-- 
GNU C Library master sources


Index Nav: [Date Index] [Subject Index] [Author Index] [Thread Index]
Message Nav: [Date Prev] [Date Next] [Thread Prev] [Thread Next]