This reverts commit ebe6e3180e.
This is wrong, as mutter's controlling TTY may not be the same
as the active VT, and in fact won't be in the case of systemd
spawning us.
The "correct" API for this is to use David Herrmann's
"Session Positions" system to switch to another VT:
http://lists.freedesktop.org/archives/systemd-devel/2013-December/014956.html
Somebody could do:
$ mv my-evil-program mutter-wayland
$ PATH=.:$PATH mutter-launch mutter-wayland
It's not secure, and it's hard to test with, so just drop it for now
We'll be relying on logind to hand us permissions in the future.
The API was changed during the patch review.
(Yes, we were depending on API which was sitting in a patch not
yet reviewed... you know, vertical integration!)
https://bugzilla.gnome.org/show_bug.cgi?id=707929
Now that we have a setuid launcher binary, we can make use of
using a private protocol through the socket we're passed at startup.
We also use the new hook in clutter-evdev to ask mutter-launch for
the FDs of the input devices we need, and we emulate the old X
DRM lock with a nested GMainContext without sources.
In the future, mutter-launch will be replaced with the new logind
API currently in development.
https://bugzilla.gnome.org/show_bug.cgi?id=705861
Set the TTY mode appropriately at startup, and clean it up
when the compositor exits. Also, take control of VT switching,
including the calls to drmSetMaster and drmDropMaster as appropriate.
In the future, we the kernel implements the mute evdev ioctl,
we'll also make sure that input devices are appropriately released.
https://bugzilla.gnome.org/show_bug.cgi?id=705861
Being a setuid binary, our LD_LIBRARY_PATH is cleared by glibc at
startup, but we need the spawned binary to see it, otherwise
jhbuild doesn't work, so hardcode it using the configured libdir.
https://bugzilla.gnome.org/show_bug.cgi?id=705861
Remove the ability to launch as a different user, which we don't
need because we're spawned by gdm or by the user manually on the
command line.
At the same time, require an active local session, and remove
the ability to run from anywhere by being in the right user group
(which automatically gives you root-like privileges)
https://bugzilla.gnome.org/show_bug.cgi?id=705861
To run mutter as a display server, one needs to acquire and
release the DRM master, which is only possible for root, so
we take advantage of weston-launch, a small setuid helper binary
written for the weston project. We import our own slightly
modified copy of it, because weston-launch only launches weston,
for security reasons.
https://bugzilla.gnome.org/show_bug.cgi?id=705861
