If anybody cares,
gmmktime returning completly bogus results. It can be easly checked out
by manually setting TZ shell variable.
Lets try it like this:
TZ=GMT+1 php -r "echo gmmktime();"
gives 1100292805
TZ=GMT+2 php -r "echo gmmktime();"
gives 1100289207
TZ=GMT+3 php -r "echo gmmktime();"
gives 1100285610
But it should return always the same time (ok, few seconds here and
there, needed to type each command..) no matter which timezone is set.
Why ? Because 'tm_gmtoff' (and gmadjust manually calculated from
'timezone' and 'is_dst' in cases where tm_gmtoff is not available) shows
number of seconds EAST from GMT (man localtime is your friend here). So
to get GMT time from, we have to substract this number from localtime,
and what is php currently doing, is adding it to localtime, which can't
be a good thing no matter how you look at it (-:
So the fix is easy:
--- ext/standard/datetime.c.orig Fri Nov 12 22:35:04 2004
+++ ext/standard/datetime.c Fri Nov 12 22:35:33 2004
@@ -256,7 +256,7 @@
gmadjust = -(is_dst ? timezone - 3600 : timezone);
#endif
#endif
-
seconds += gmadjust;
-
seconds -= gmadjust; } RETURN_LONG(seconds);
If anybody cares,
gmmktime returning completly bogus results. It can be easly checked out
by manually setting TZ shell variable.
I can reproduce it, and I'll investigate whether this is not going to
break other things.
Derick
--
Derick Rethans
http://derickrethans.nl | http://ez.no | http://xdebug.org
Yes, please do so.
I just found the fix by carefully reading man pages for localtime and
tzset.
If anybody cares,
gmmktime returning completly bogus results. It can be easly checked out
by manually setting TZ shell variable.I can reproduce it, and I'll investigate whether this is not going to
break other things.Derick
--
Vladimir Zidar, Programmer
MindNever Foodstuff TRDG.
Head Office Branch
Tel: +381-63-550161, +385-98-9574261
http://www.mindnever.org, icq: 15414204, mail: mr_W@mindnever.org
On Mon, 15 Nov 2004 16:04:46 +0100
Vladimir Zidar vladimir@mindnever.org wrote:
If anybody cares,
gmmktime returning completly bogus results. It can be easly checked
out by manually setting TZ shell variable.Lets try it like this:
TZ=GMT+1 php -r "echo
gmmktime();"gives 1100292805
TZ=GMT+2 php -r "echo
gmmktime();"gives 1100289207
TZ=GMT+3 php -r "echo
gmmktime();"gives 1100285610
But it should return always the same time (ok, few seconds here and
there, needed to type each command..) no matter which timezone is set.
I wonder why it wasn't noticed before, cause CVS says it was introduced ages ago:
http://cvs.php.net/co.php/php-src/ext/standard/datetime.c?r=1.8
http://cvs.php.net/diff.php/php-src/ext/standard/datetime.c?r1=1.7&r2=1.8&ty=u
--
Wbr,
Antony Dovgal aka tony2001
tony2001@phpclub.net || antony@dovgal.com
So the fix is easy:
--- ext/standard/datetime.c.orig Fri Nov 12 22:35:04 2004
+++ ext/standard/datetime.c Fri Nov 12 22:35:33 2004
@@ -256,7 +256,7 @@
gmadjust = -(is_dst ? timezone - 3600 : timezone);
#endif
#endif
seconds += gmadjust;
seconds -= gmadjust; } RETURN_LONG(seconds);
This fix is wrong, the example now returns definitely the wrong answer:
derick@kossu:/dat/dev/php/php-5.0dev$ cat ext/standard/tests/time/bug30096.php
<?php
echo gmdate("H:i:s Y-m-d", gmmktime(02,00,01, 03,28,2004));
?>
derick@kossu:/dat/dev/php/php-5.0dev$ sapi/cli/php ext/standard/tests/time/bug30096.php
23:00:01 2004-03-27
This bug has nothing to do with the wrong direction of the adjustment,
but more with the chancing to DST at that date.
regards,
Derick
--
Derick Rethans
http://derickrethans.nl | http://ez.no | http://xdebug.org
But then whole function php_mktime() is wrong, as in case where gm=1,
you expect that parameters you pass are GMT, and still you fill defaults
with localtime. Also, later, if gm=1, timezone adjustment is in use, but
with parameters that are in GMT.
So the real good fix would be to remove timezone stuff completly out of
there, and make another function in pair with php_localtime_r, that
returns GMT, and to use it when gm=1.
So the fix is easy:
--- ext/standard/datetime.c.orig Fri Nov 12 22:35:04 2004
+++ ext/standard/datetime.c Fri Nov 12 22:35:33 2004
@@ -256,7 +256,7 @@
gmadjust = -(is_dst ? timezone - 3600 : timezone);
#endif
#endif
seconds += gmadjust;
seconds -= gmadjust; } RETURN_LONG(seconds);This fix is wrong, the example now returns definitely the wrong answer:
derick@kossu:/dat/dev/php/php-5.0dev$ cat ext/standard/tests/time/bug30096.php
<?php
echo gmdate("H:i:s Y-m-d", gmmktime(02,00,01, 03,28,2004));
?>derick@kossu:/dat/dev/php/php-5.0dev$ sapi/cli/php ext/standard/tests/time/bug30096.php
23:00:01 2004-03-27This bug has nothing to do with the wrong direction of the adjustment,
but more with the chancing to DST at that date.regards,
Derick
--
Vladimir Zidar, Programmer
MindNever Foodstuff TRDG.
Head Office Branch
Tel: +381-63-550161, +385-98-9574261
http://www.mindnever.org, icq: 15414204, mail: mr_W@mindnever.org
But then whole function php_mktime() is wrong, as in case where gm=1,
you expect that parameters you pass are GMT, and still you fill defaults
with localtime. Also, later, if gm=1, timezone adjustment is in use, but
with parameters that are in GMT.So the real good fix would be to remove timezone stuff completly out of
there, and make another function in pair with php_localtime_r, that
returns GMT, and to use it when gm=1.
Sure, that's why I'm rewriting this stuff for PHP 5 ;-)
regards,
Derick
--
Derick Rethans
http://derickrethans.nl | http://ez.no | http://xdebug.org
But then whole function php_mktime() is wrong, as in case where gm=1,
you expect that parameters you pass are GMT, and still you fill defaults
with localtime. Also, later, if gm=1, timezone adjustment is in use, but
with parameters that are in GMT.So the real good fix would be to remove timezone stuff completly out of
there, and make another function in pair with php_localtime_r, that
returns GMT, and to use it when gm=1.Sure, that's why I'm rewriting this stuff for PHP 5 ;-)
I can see now that there is php_gmtime_r() function also. Can we use this when gm=1, and forget about timezone there ?
I'll check now.