Each of the backends becomes a plugin. This allows kwin_wayland to load
the requested plugin and kwin itself doesn't need to link all the
libraries needed. E.g. libdrm is no longer linked if running kwin_x11.
Also this allows to create backends for the non-standard EGL platforms
(examples could be raspberrypi or Android devices).
LogindIntegration starts monitoring the Active property on the session
and emits a signal when the state changes. The LibInput::Connection
connects to this signal during the setup and uses it to suspend/resume
the libinput context.
With libinput we have the problem that we need to have privileges to
open the device files. In order to not need wrappers or suid bits, we
use logind. This means that kwin_wayland has to be the session controler.
A LogindIntegration is added to connect to logind and wrap the dbus
calls. This is based on the logind integration done for ksld in
ksmserver. The LogindIntegration is started by Workspace and the
InputRedirection tries to become the session controller and starts the
libinput integration only after this succeeded.
Martin Gräßlin