Update.

1998-10-08  Paul Eggert  <eggert@twinsun.com>

	* time/mktime.c (__mktime_internal): When the requested time falls
	in a spring-forward gap of size DT, return a time that is DT away
	from the requested time, preferring a time whose tm_isdst differs
	from the requested value.  Bump the max number of probes from 4 to
	6 to account for the extra probes needed to discover a
	spring-forward gap in the worst case.

1998-10-07 17:05  Ulrich Drepper  <drepper@cygnus.com>

	* sysdeps/unix/sysv/linux/alpha/ioperm.c: Improve the autodetection
	of the weird alpha architectures.
	Patch by Cristian Gafton <gafton@redhat.com>.

1998-02-18 23:31  Richard Henderson  <rth@cygnus.com>

	* sysdeps/unix/sysv/linux/alpha/ioperm.c: Add support for
	RAWHIDE and TSUNAMI.  Patch from Jay.Estabrook@digital.com.

diff --git a/ChangeLog b/ChangeLog
index 5d4adbe..ed49343 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,23 @@
+1998-10-08  Paul Eggert  <eggert@twinsun.com>
+
+       * time/mktime.c (__mktime_internal): When the requested time falls
+       in a spring-forward gap of size DT, return a time that is DT away
+       from the requested time, preferring a time whose tm_isdst differs
+       from the requested value.  Bump the max number of probes from 4 to
+       6 to account for the extra probes needed to discover a
+       spring-forward gap in the worst case.
+
+1998-10-07 17:05  Ulrich Drepper  <drepper@cygnus.com>
+
+       * sysdeps/unix/sysv/linux/alpha/ioperm.c: Improve the autodetection
+       of the weird alpha architectures.
+       Patch by Cristian Gafton <gafton@redhat.com>.
+
+1998-02-18 23:31  Richard Henderson  <rth@cygnus.com>
+
+       * sysdeps/unix/sysv/linux/alpha/ioperm.c: Add support for
+       RAWHIDE and TSUNAMI.  Patch from Jay.Estabrook@digital.com.
+
 1998-10-07  Ulrich Drepper  <drepper@cygnus.com>
 
        * elf/dl-open.c (_dl_global_scope_alloc): Make global.

diff --git a/time/mktime.c b/time/mktime.c
index ce691c8..7b93f1d 100644 (file)
--- a/time/mktime.c
+++ b/time/mktime.c
@@ -256,14 +256,14 @@ __mktime_internal (tp, convert, offset)
      struct tm *(*convert) __P ((const time_t *, struct tm *));
      time_t *offset;
 {
-  time_t t, dt, t0;
+  time_t t, dt, t0, t1, t2;
   struct tm tm;
 
   /* The maximum number of probes (calls to CONVERT) should be enough
      to handle any combinations of time zone rule changes, solar time,
-     and leap seconds.  POSIX.1 prohibits leap seconds, but some hosts
-     have them anyway.  */
-  int remaining_probes = 4;
+     leap seconds, and oscillations around a spring-forward gap.
+     POSIX.1 prohibits leap seconds, but some hosts have them anyway.  */
+  int remaining_probes = 6;
 
   /* Time requested.  Copy it in case CONVERT modifies *TP; this can
      occur if TP is localtime's returned value and CONVERT is localtime.  */
@@ -309,15 +309,27 @@ __mktime_internal (tp, convert, offset)
   tm.tm_yday = tm.tm_hour = tm.tm_min = tm.tm_sec = 0;
   t0 = ydhms_tm_diff (year, yday, hour, min, sec, &tm);
 
-  for (t = t0 + *offset;
+  for (t = t1 = t2 = t0 + *offset;
        (dt = ydhms_tm_diff (year, yday, hour, min, sec,
                            ranged_convert (convert, &t, &tm)));
-       t += dt)
-    if (--remaining_probes == 0)
+       t1 = t2, t2 = t, t += dt)
+    if (t == t1 && t != t2
+       && (isdst < 0 || 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.  In practice,
+        this is more useful than returning -1.  */
+      break;
+    else if (--remaining_probes == 0)
       return -1;
 
-  /* Check whether tm.tm_isdst has the requested value, if any.  */
-  if (0 <= isdst && 0 <= tm.tm_isdst)
+  /* If we have a match, check whether tm.tm_isdst has the requested
+     value, if any.  */
+  if (dt == 0 && 0 <= isdst && 0 <= tm.tm_isdst)
     {
       int dst_diff = (isdst != 0) - (tm.tm_isdst != 0);
       if (dst_diff)