[TYPO3-dev] stdwrap->strftime and timezone

[David Nyffenegger]

I have now discovered the behavior...

When entering in the BE a time value, it is done without any timezone in 
mind. E.g. if I enter 20:00, then 20 * 3600 = 72000 will be stored in 
the DB table. The rendering in the backend is done with the 
TCA->config->eval mapping, which in this case is t3lib_BEfunc::time(). 
This function doesn't use strftime (surprise, surprise), instead it is 
made "by hand":
    function time($value)    {
        $hh = floor($value/3600);
        $min = floor(($value-$hh*3600)/60);
        $sec = $value-$hh*3600-$min*60;
        $l = 
sprintf('%02d',$hh).':'.sprintf('%02d',$min).':'.sprintf('%02d',$sec);
        return $l;
    }

This explains, why in the BE, the time inputted is the time shown.

BUT, in the FE, the strftime function is used, which is affected by the 
setlocale() function, which is set according the TS config.locale_all 
value, which implies in my case a time zone of GMT+1, i.e. strftime adds 
the magic hour because it assumes UTC as input.

One solution would be to change the BE code in order to store only real 
unix timestamps in the database (UTC). This would affect the rendering 
as well as the processing of the form input. The other solution: when 
rendering with strftime be aware that user fields containing date and 
time information will be in the users timezone, thus transform them 
first back to UTC before using strftime.

Regards
David