[PATCH 00/29] Pointer barrier events and barrier releases

[Peter Hutterer]

This is the server-side for the pointer-barrier patches, proposed as XI 2.3.
It adds events for pointer barriers (when the pointer hits vs leaves the
arrier) and the ability to release a pointer across. I hereby propose this
for the 1.14 release.

Trees for testing available from:
    git://people.freedesktop.org/~whot/xserver.git barriers
    git://people.freedesktop.org/~whot/libXi.git barriers
    git://people.freedesktop.org/~whot/inputproto.git barriers

More verbose description:
http://who-t.blogspot.com.au/2012/12/whats-new-in-xi-23-pointer-barrier.html

KNOWN BROKEN: events/releases in the MPX case, though it works fine if the
barrier doesn't apply to more than one device at a time. 
- releases currently ignore the device id
- too many leave events may be sent if a barrier applies to multiple
  devices
I've got patches here that fix this, but they're not quite finished yet.
Either way, that's a narrow use-case and it will be fixed before the
release.

Many thanks to Jasper St. Pierre, who did most of the legwork here. And of
course Chris Halse-Rogers who started with this feature quite a while ago.

Cheers,
  Peter