#43056 [Com]: unixtojd() behavior is ill-specified

ID: 43056 Comment by: vorlon at debian dot org Reported By: vorlon at debian dot org Status: Feedback Bug Type: Date/time related Operating System: * PHP Version: 5.2.4 New Comment: No, I'm thankfully free of maintaining PHP packages now, I have no intention of chasing CVS tarballs to check whether you've fixed the code. Previous Comments: ------------------------------------------------------------------------ [2008-10-26 23:47:00] jani@php.net Please try using this CVS snapshot: http://snaps.php.net/php5.2-latest.tar.gz For Windows: http://windows.php.net/snapshots/ ------------------------------------------------------------------------ [2007-10-21 06:22:15] vorlon at debian dot org Description: ------------ The calendar extension's unixtojd() function is described in the php manual as simply: unixtojd — Convert Unix timestamp to Julian Day No further explanation is given for how a Julian Day is defined in this case. However, if we use the definition given at <http://www.decimaltime.hynes.net/dates.html#jdn> which appears to be the normal astronomical meaning of a Julian Day, a Julian Day should be measured from noon GMT (or UT). The problem is that the unixtojd() function uses php_localtime_r() to convert a given UNIX timestamp to a time_t struct - which means the base Gregorian date used for the conversion is calculated in the local timezone, not in GMT. This function should use php_gmtime_r() instead. This problem was detected when running the PHP testsuite with TZ=UTC set - the ext/calendar/tests/unixtojd.phpt test expects a value that is only returned in a timezone west of GMT! (Separately, I see nowhere that the 12h offset is taken into account, so in practice all unixtojd() results are currently calculated from midnight in the local timezone.) Reproduce code: --------------- <?php setenv('TZ=America/Los_Angeles'); echo unixtojd(1000000000). "\n"; ?> Expected result: ---------------- 2452162 Actual result: -------------- 2452161 ------------------------------------------------------------------------ -- Edit this bug report at http://bugs.php.net/?id=43056&edit=1