In the recent refactor we made it so environment variables got synced to
the Application::processStartupEnvironment.
It then seemed safe and cleaner to remove the qputenv calls, but this
was not the case. It regressed the unit tests on CI and kglobalaccel
which is another path where kwin spawns clients.
This way if kwin_wayland crashes we don't need to ensure that new
environment variables need to get synced across the new env.
This fixes an issue where spawning an xwayland application from a
wayland window that survives a crash would fail.
By moving the logic here we no longer need to wait for kwin_wayland to
start before starting plasmashell or even ksmserver as all environment
variables are set. As long as the wrapper is ready we can continue
starting and clients will just block on connect.
That should still allow for both a lot of optimisations both for speed
and cleaning up the startplasma-wayland scripts.
This will be addressed in follow up patches.
Use of kwin_wayland directly with xwayland is still supported for
testing.
The initial goal of kwin_wrapper was that it would set up all relevant
environment variables that will be used by the clients of kwin.
This meant having to cache old variables before we overrode them and
pass additional settings to the backends for the old wayland_display. It
works, but with X11 about to move too ends up being unnecessarily
complex. In hindsight it's easier for kwin to have the environment
represent the platform it is currently on, and have kwin explicitly set
variables in the QProcessEnvironment of the session it forks itnto.
This patch is changed so that we set the wayland socket name used by the
wrapper explicitly which is then used by the process environment kwin
uses for the main session.
The backend can now optionally wait for the scene to be created before
it updates its outputs, which is necessary for better atomic tests in
the DRM backend.
As is, kwin with the drm backend results in the most pleasant user
experience on Wayland. Given that and the fbdev being about to be
dropped, making libdrm a required dependency seems a reasonable decision.
Platform::prepareShutdown() was introduced to work around the issue
where the platform accesses destroyed OutputDeviceInterface objects.
Since we no longer query OutputDeviceInterface for output info, the
Platform::prepareShutdown() function can be dropped.
At the moment, the session code is far from being extensible. If we
decide to add support for libseatd, it will be a challenging task with
the current design of session management code. The goal of this
refactoring is to fix that.
Another motivation behind this change is to prepare session related code
for upstreaming to kwayland-server where it belongs.
Once in a while, we receive complaints from other fellow KDE developers
about the file organization of kwin. This change addresses some of those
complaints by moving all of source code in a separate directory, src/,
thus making the project structure more traditional. Things such as tests
are kept in their own toplevel directories.
This change may wreak havoc on merge requests that add new files to kwin,
but if a patch modifies an already existing file, git should be smart
enough to figure out that the file has been relocated.
We may potentially split the src/ directory further to make navigating
the source code easier, but hopefully this is good enough already.
