aboutsummaryrefslogtreecommitdiff
path: root/time/mktime.c
diff options
context:
space:
mode:
Diffstat (limited to 'time/mktime.c')
-rw-r--r--time/mktime.c44
1 files changed, 16 insertions, 28 deletions
diff --git a/time/mktime.c b/time/mktime.c
index 6135d70..2908db0 100644
--- a/time/mktime.c
+++ b/time/mktime.c
@@ -350,44 +350,32 @@ __mktime_internal (tp, convert, offset)
/* If we have a match, check whether tm.tm_isdst has the requested
value, if any. */
- if (dt == 0 && isdst >= 0 && isdst != tm.tm_isdst)
+ if (dt == 0 && 0 <= isdst && 0 <= tm.tm_isdst)
{
int dst_diff = (isdst != 0) - (tm.tm_isdst != 0);
if (dst_diff)
{
- /* Move three hours in the direction indicated by the disagreement,
+ /* Move two hours in the direction indicated by the disagreement,
probe some more, and switch to a new time if found.
The largest known fallback due to daylight savings is two hours:
- once, in Newfoundland, 1988-10-30 02:00 -> 00:00.
- But some programs (e.g. testsuites) probe for larger differences
- between DST and normal time so switch by three hours. No
- normal program does this so we do not account for more than
- three hours difference. */
- time_t ot = t - 3 * 60 * 60 * dst_diff;
- struct tm otm;
- struct tm tmptm;
-
- otm.tm_isdst = -1;
-
+ once, in Newfoundland, 1988-10-30 02:00 -> 00:00. */
+ time_t ot = t - 2 * 60 * 60 * dst_diff;
while (--remaining_probes != 0)
{
- if (! (dt = ydhms_tm_diff (year, yday, hour, min, sec,
- ranged_convert (convert, &ot,
- &tmptm)))
- || tmptm.tm_isdst != isdst)
- break;
-
- otm = tmptm;
- ot += dt;
- if (ot == t)
+ struct tm otm;
+ dt = ydhms_tm_diff (year, yday, hour, min, sec,
+ ranged_convert (convert, &ot, &otm));
+ if (dt == 0
+ || (ot + dt == t
+ && dst_diff == (isdst != 0) - (tm.tm_isdst != 0)))
+ {
+ t = ot;
+ tm = otm;
+ break;
+ }
+ if ((ot += dt) == t)
break; /* Avoid a redundant probe. */
}
-
- if (otm.tm_isdst != -1)
- {
- t = ot;
- tm = otm;
- }
}
}