On 15/7/19 1:34, Florian Westphal wrote:
Even when relying on kernel time zone for everything, I don't see
how we can support cross-day ("22:23-00:42") matching, as the range is
invalid.
And that as well of course, swap and invert should work just fine.
Second problem:
Only solution I see is to change kernel patch to rely on
sys_tz, just like xt_time, with all the pain this brings.
This stands, as the weekday is computed in the kernel, we will
need to bring sys_tz into this on the kernel side, the current
code uses UTC so we could be several hours off.
This can be restricted to the 'DAY' case of course.
I see... Thank you. You saved me hours of work figuring this out.
So, for the TIME case we just swap left and right, and for the DAY case,
just add (tz_minuteswest * 60) to the seconds before breaking it into
day/mon/year?
And what does tz_dsttime do? gettimeofday(2) man says it is there for
historical reasons and should be ignored on Linux. But I don't know what
is it for in the kernel.