Add the screensaver interface to the desktop-shell protocol file. Also
add stubs for it in the compositor, and make wscreensaver to bind to the
screensaver interface. Wscreensaver gets a new option --demo to retain
the current behaviour as a regular wayland client.
When a screensaver application starts, it should bind to the screensaver
interface, enumerate all outputs, create a surface per output, and
register those surfaces via screensaver::set_surface request. Then it
continues with the usual animation loop, waiting for frame events. The
compositor will decide, when the given screensaver surfaces are
displayed. A screensaver application should respond to outputs coming
and going away by creating and destroying surfaces.
The compositor is supposed to activate a screensaver by exec'ing it, and
stop the screensaver by killing the client process. Only one client may
be bound to the screensaver interface at a time. If there already is a
client, the compositor could either kill it first, or not exec a new
one.
Signed-off-by: Pekka Paalanen <ppaalanen@gmail.com>
Change desktop-shell protocol to use wl_shell_surface instead of
wl_surface.
Adapt the desktop-shell client and the shell plugin.
Signed-off-by: Pekka Paalanen <ppaalanen@gmail.com>
Add protocol and functions for supporting screen locking, triggered by
activity timeout.
After activity timeout, compositor starts the fade to black, and then
enters SLEEPING state. At that point it calls lock() in the shell
plugin.
When input events trigger a wakeup, unlock() in the shell plugin is
called. This sends prepare_lock_surface event to the desktop-shell
client. The screen stays locked while the compositor starts fade-in.
At this point, desktop-shell client usually creates a surface for the
unlocking GUI (e.g. a password prompt), and sends it with the
set_lock_surface request. The compositor supposedly shows and allows
interaction only with the given lock surface (not yet implemented).
When desktop-shell has authenticated the user, or instead of issuing
set_lock_surface, it sends the unlock request. Upon receiving the unlock
request, the shell plugin unlocks the screen.
If desktop-shell client dies, the screen is unlocked automatically.
Signed-off-by: Pekka Paalanen <ppaalanen@gmail.com>
