We don't want to skip running initial setup if wayland
fell back or something.

This commit makes sure we only stop trying to start initial-setup
after it's completed.

https://bugzilla.gnome.org/show_bug.cgi?id=789434

This provides gnome-shell with a way to use the new interface.

https://bugzilla.gnome.org/show_bug.cgi?id=788851

This commit adds one PAM extension, a "Choice List" using the
new PAM_BINARY_PROMPT protocol added in the previous commit.  The
PAM module sends a list of (key, row text) pairs, and GDM ferries
the request to gnome-shell using a new user verifier sub-interface.

gnome-shell should present the list to the user and pass back the
corresponding key, which GDM ferries back to the PAM module.

Note this commit is only the daemon side. A subsequent commit will
add the libgdm API needed for gnome-shell to actually deal with
this new PAM extension.

https://bugzilla.gnome.org/show_bug.cgi?id=788851

This abuses PAM_BINARY_PROMPT for our own nefarious purposes.
The way it works is GDM advertises what "extensions" it supports
with the environment variable, GDM_SUPPORTED_PAM_EXTENSIONS (a space
separated list of reverse dns notation names). PAM services that
support this protocol, will read the environment variable, and
check for extension strings they support. They then know that sending
PAM_BINARY_PROMPT won't blow up, and know what format to use for the
binary data.  The type field of the structure is the index of the
string from the environment variable.

This commit is just foundation work. It doesn't actually add any
extensions.

https://bugzilla.gnome.org/show_bug.cgi?id=788851

Right now the worker interface has three methods for starting
a conversation: Setup, SetupForUser, SetupForProgram

Each of these method calls take a large number of overlapping arguments.
Extending these argument lists is painful and breaks upgrades.

This commit adds a new, fourth call, Initialize, which supercedes the
others and just takes a vardict, which is much more extensible.

https://bugzilla.gnome.org/show_bug.cgi?id=788851

Right now we always give text responses back to pam modules,
so the response variable is named response_text.  That's going
to change in the future, when we introduce private protocol for
the module to talk to GDM.

As prep work for that change, rename "response_text" to "response".

https://bugzilla.gnome.org/show_bug.cgi?id=788851

Olivier Tilloy authored Oct 17, 2017 and Iain Lane committed Oct 17, 2017

This is done under the assumption that they are meant for Wayland only.
It is expected that a session called "foo" would have a "foo.desktop" file
under wayland-sessions/, a fallback "foo.desktop" under xsessions/, and
another "foo-xorg.desktop" under xsessions (that may simply be a symlink
to "foo.desktop") specifically for Wayland.

https://bugzilla.gnome.org/show_bug.cgi?id=788552

commit 7e8243eecd0233f7ab92519207f2520794439b11 introduced a
compiler warning if gdm is built with --enable-wayland and
--disable-user-display-server

This commit fixes that.

https://bugzilla.gnome.org/show_bug.cgi?id=788963

This used to be done with a special greeter indicator, but it's
much simpler to just define the presets accordingly.

https://bugzilla.gnome.org/show_bug.cgi?id=788942

If the user logs out we may detect the session dying before
we detect the X server dying.  If that happens, then we
currently don't wait for the X server to exit before starting
a new X server.

This commit makes sure to explicitly kill the X server and wait
for its death before proceeding.

https://bugzilla.gnome.org/show_bug.cgi?id=788786

Right now we end up writing wtmp entries for the login screen
user into /var/log/wtmp, but with a funky username of "(unknown)".

The login screen session shouldn't get a wtmp entry, and we
shouldn't ever add wtmp entries for sessions we don't know the username
for.

This commit fixes that.

https://bugzilla.gnome.org/show_bug.cgi?id=788784

Use EXIT_ defines for readibility.
There were some exit codes > 1, but they don't seem to be checked by any of the
parent process code. This does mean that the logs might have changed, but
modern logging techniques have probably made this obsolete.

https://bugzilla.gnome.org/show_bug.cgi?id=788307

This reverts commit 6594b1f2.

https://bugzilla.gnome.org/show_bug.cgi?id=787287

This will either force the initial setup to run or not to run

Fixes #787286

https://bugzilla.gnome.org/show_bug.cgi?id=788303

Remove goto that no longer does anything.
Consistently use return instead of exit() from main.
Print pre-log errors to stderr to ensure they're visible regardless of GLib
settings.

https://bugzilla.gnome.org/show_bug.cgi?id=788302

The root check doesn't require settings and may be the cause of settings
failing to load.

https://bugzilla.gnome.org/show_bug.cgi?id=788301

https://bugzilla.gnome.org/show_bug.cgi?id=788300

https://bugzilla.gnome.org/show_bug.cgi?id=788299

If the X server is started as part of the session, we don't know the
display up front. So don't try to encode the display in the log in that
case.

https://bugzilla.gnome.org/show_bug.cgi?id=787989

commit 2a3d5a7c attempted to fix
the signal prototype of on_client_disconnected to match the marshalled
arguments.  Unfortunately, the handler is used for two different
signals:

1) when a user chooses "Disconnect" from the chooser menu
2) when a user closes the Xephyr window (or turns off the thin client
or whatever)

The signals have slightly different prototypes, so commit 2a3d5a7c
fixed 2), but broke 1).

This commit massages the signal connections and handler signature to
work for both cases.

https://bugzilla.gnome.org/show_bug.cgi?id=787987

Eventually, our software should become "multi-seat aware",
where it takes into account multiple seats at a time
for the user (even if it's just putting up a dialog saying
"user is busy" on all but one seat).

We're not there yet. And user bus currently breaks XDMCP
(which should really spawn session with its own separate user,
 but again, we're not there yet).

This commit changes GDM to start a session bus for all non-seat0
displays, as a near-term workaround.

https://bugzilla.gnome.org/show_bug.cgi?id=787943

seat0 is the only seat that supports VTs, so don't ever try to
change VTs if not on seat0.

https://bugzilla.gnome.org/show_bug.cgi?id=787943

Right now we hide wayland sessions from the list if the greeter isn't
wayland.  The greeter is never wayland if built with
--disable-user-display-server.

This commit allows wayland sessions for the user session, when
--disable-user-display-server --enable-wayland-support is specified,
even though the greeter won't use wayland itself.

https://bugzilla.gnome.org/show_bug.cgi?id=787899

There's a bug when changing the language of the login screen to a different
one than the user session's language, which causes the new language to be
used both in the login screen AND the user session if you simply logout and
then re-login without rebooting. Restarting the machine after that point
normalizes things, getting the new language used only in the login screen
but not in the user session.

Making sure that the user language is always saved by the session seems
without checking whether is the same than the default language fixes this.

Based on a patch by Felipe Erias Morandeira <femorandeira@igalia.com>

https://bugzilla.gnome.org/show_bug.cgi?id=786422

prevent gnome-shell crash when testing Wayland session
if Xwayland isn't installed.

https://bugzilla.gnome.org/show_bug.cgi?787837

When the user has not ever selected a session from the selector, we will
log them into the `fallback' session, which is calculated by looking at
all installed sessions and picking the first one in the list.

There is a bug that the visually selected session presented in the
greeter can be different from the fallback session calculated inside
GDM. This happens because the two sort sessions differently.

Inside GDM we calculate the fallback session by comparing the full
basename of the file:

>>> GLib.strcmp0("gnome-xorg.desktop", "gnome.desktop")
-1

Whereas gnome-shell calls gdm_get_session_ids(), which returns IDs
without the ".desktop" extension. Those are then sorted:

>>> GLib.strcmp0("gnome-xorg", "gnome")
45

which gives a different ordering.

Fix this bug by calculating the fallback session in the same way, by
removing ".desktop" from the filename.

https://bugs.launchpad.net/ubuntu/+source/gnome-session/+bug/1705157

https://bugzilla.gnome.org/show_bug.cgi?id=787304