Currently, libobs contains two inhibitors: the portal-based one, and the
regular one based on each desktop environment's session manager. The portal
inhibitor takes precedence over the session manager one, when available.
Like the session manager inhibitor, the portal inhibitor performs all D-Bus
calls synchronously in the calling thread, which can lead to stalls. This is
not a good practice.
Make the portal inhibitor asynchronous, by using g_dbus_connection_call()
instead of g_dbus_connection_call_sync(). If an uninhibit call is made
before the previous inhibit call finishes, cancel the inhibit call instead.
Fixesobsproject/obs-studio#5314
XDG Portals provide a plethora of features meant to be used inside and
outside sandboxed environments. OBS Studio currently uses portals to
implement Wayland-compatible monitor and window captures.
However, OBS Studio performs another action that can be done through
portals: inhibit the screensaver. Under the Desktop portal (the same
used by the captures mentioned above), there is an "Inhibit" portal
that provides session inhibition.
Add a new portal-based inhibitor. This inhibitor is only used when the
Desktop portal is available and running; the previous D-Bus implementation
is used in the absence of the portal. Because it's basically another set
of D-Bus operations, wrap the new portal inhibitor under the HAVE_DBUS
call too.
