This makes it easy for compositors to handle situations where the
DRM or libinput backend becomes unavailable. Compositors can listen
the destroy event of the multi backend returned by
wlr_backend_autocreate() and decide what to do.
Some users might want to destroy the multi backend when a child
backend is being destroyed. However, they can't destroy the multi
backend if it's already in the process of being destroyed.
The destroy signal was changed to be emitted after destroying child
backends in babdd6ccf7 ("backend: fix use-after-free when destroying
backends"). However, this was done to accomodate for an old
"output_remove" event on backends, which has long been dropped in
favor of wlr_output.events.destroy.
This patch follows the same principle as 5d639394f3
("types/output: emit destroy event before destroying global").
A motivating example of such problem - Zoom's popups that open on button presses.
Before this fix the popup would flicker and immediately disappear - because the PID is not yet
available for the verification (as the surface has not been associated yet), wlroots would refuse to
focus the popup and instead focus the previous window. This leads QT to interpret this as a sign to
close the popup.
This change moves the PID aqcuisition to an earlier phase - just where the window is created.
wl_drm is a legacy interface superseded by the linux-dmabuf
protocol. All clients should migrate.
As a first step, stop creating the wl_drm global by default.
This should let us discover any remaining issues in clients.
Compositors can still manually create the global if they want to.
As a second step, we can completely drop our implementation.
wlr_output.refresh is populated by core wlr_output, and thus will
be zero for a custom mode with an unset refresh rate.
Save the refresh rate from the drmModeModeInfo in wlr_drm_connector
instead.
Closes: https://gitlab.freedesktop.org/wlroots/wlroots/-/issues/3791
Félix Poisot
Simon Ser
Grigory Kirillov
Sarunas Valaskevicius
Alexander Orzechowski
Kirill Primak
Isaac Freund
MaxVerevkin