[vlc-devel] [PATCH] src: implement monotonic clock for osx

[David Fuhrmann]

Hi Remi,

Am 10.12.2013 um 18:36 schrieb Rémi Denis-Courmont <remi at remlab.net>:

> On Tue, 10 Dec 2013 18:10:55 +0100, david.fuhrmann at gmail.com wrote:
>> From: David Fuhrmann <david.fuhrmann at googlemail.com>
>> 
>> mach_absolute_time seems to be the fastest (and preferred) way to access
>> the high precision timer. It counts mach time units since the last
> system
>> boot. mach_timebase_info provides a conversion factor to transform the
>> value
>> into nano seconds.
> 
> I fail to see how this fits in src/posix(/thread.c)

Yes, strictly speaking it should be moved into the darwin directory. But as most of the code in posix/thread.c is reused in darwin, it may be better to just modify the file in the posix directory for now. And darwin is also called a more or less posix compatible os. :-)

> but most importantly I
> fail to see how this can work without clock selection.

I suppose you are talking about the lack of vlc_clock_id definition?
It works without that because this variable is only used in the cases _POSIX_CLOCK_SELECTION > 0 or _POSIX_TIMERS > 0. Both defines are -1 on osx, so its not needed. And in fact, for the fallback case which was used before (using gettimeofday), this variable is not defined, either.

With best regards,

David