About SMP and stuff

[Christophe Massiot]

I had some time yesterday, so I rewrote the video decoder to take
advantage of several processors. You can turn it on with
---smp <number of processors to use>
It is also fully configurable at runtime, and a primitive to do it is
in input_ext-intf.c, but <hint> I need plug-in developers to update
their interface plug-ins to use it </hint>.

Interface developers are strongly encouraged to look at the bottom of
src/input/input_ext-intf.c for new primitives.

IMPORTANT NOTE FOR PORTS :
************************
I needed the function pthread_cond_broadcast, which is not wrapped in
threads.h. I remind you that vlc_cond_signal only awakens ONE waiting
thread, whereas vlc_cond_broadcast awakens ALL threads waiting for the
condition (It seems that some implementations of vlc_cond_signal are
wrong...).

I only implemented vlc_cond_broadcast for pthreads, so I need specialists
to write functions for cthreads, bethreads, etc. For the moment
SMP mode will only work well under systems providing pthreads.

-- 
Christophe Massiot.