For non-`seat0` seats, attaching a graphics card to a seat can
lead to it getting created. This is because the graphics device
is a "master device" which means that device is a seat-defining
device.
`seat0` may get created, even before the graphics driver is loaded,
though. This is because the graphics driver is loaded
asynchronously at startup, and `seat0` is the primary seat of
system, associated with the system VTs.
When a graphics card is attached to a seat the `CanGraphical`
property on that seat will flip to `true`.
For seats that haven't been created yet (non-`seat0` seats), this
leads to `seat_start` getting called which ultimately causes the
seat to get serialized to `/run/systemd/seats`.
For `seat0`, which is already created, `seat_start` will return
immediately, which means the updated `CanGraphical` state will
never get written to `/run/systemd/seats`.
The end result is that clients querying `sd_seat_can_graphical`
won't get the correct answer for `seat0` in cases where the
graphics device takes a long time to load until some other peice
of seat state is updated.
This commit fixes the problem by calling `seat_save` explicitly
for already running seats at the time a graphics device is
attached.
Sometimes it's useful to provide a default value during an environment
expansion, if the environment variable isn't already set.
For instance $XDG_DATA_DIRS is suppose to default to:
/usr/local/share/:/usr/share/
if it's not yet set. That means callers wishing to augment
XDG_DATA_DIRS need to manually add those two values.
This commit changes replace_env to support the following shell
compatible default value syntax:
XDG_DATA_DIRS=/foo:${XDG_DATA_DIRS:-/usr/local/share/:/usr/share}
Likewise, it's useful to provide an alternate value during an
environment expansion, if the environment variable isn't already set.
For instance, $LD_LIBRARY_PATH will inadvertently search the current
working directory if it starts or ends with a colon, so the following
is usually wrong:
LD_LIBRARY_PATH=/foo/lib:${LD_LIBRARY_PATH}
To address that, this changes replace_env to support the following
shell compatible alternate value syntax:
LD_LIBRARY_PATH=/foo/lib${LD_LIBRARY_PATH:+:${LD_LIBRARY_PATH}}
[zj: gate the new syntax under REPLACE_ENV_ALLOW_EXTENDED switch, so
existing callers are not modified.]
Add support for /etc/environment and document the changes to the user manager
to automatically import environment *.conf files from:
~/.config/environment.d/
/etc/environment.d/
/run/environment.d/
/usr/local/lib/environment.d/
/usr/lib/environment.d/
/etc/environment
merge_env_file is a new function, that's like load_env_file, but takes a
pre-existing environment as an input argument. New environment entries are
merged. Variable expansion is performed.
Falling back to the process environment is supported (when a flag is set).
Alternatively this could be implemented as passing an additional fallback
environment array, but later on we're adding another flag to allow braceless
expansion, and the two flags can be combined in one arg, so there's less
stuff to pass around.
strempty() converts a NULL value to empty string, so
that it can be passed on to functions that don't support NULL.
replace_env calls strempty before passing its value on to strappend.
strappend supports NULL just fine, though, so this commit drops the
strempty call.
If an environment array has duplicates, strv_env_get_n returns
the results for the first match. This is wrong, because later
entries in the environment are supposed to replace earlier
entries.
The tty associated with a VT should be owned by the owner of the session
running on the VT. This is important for supporting a socket activated X
server, since the X server will open the tty itself.
This commit makes sure to chown the tty any time a session is
created and and chown it back to root any time the session
is removed. This behavior is copied from /bin/login.
We need to tell the X server to grab the keyboards
and mice associated with a hotplugged seat, so that
it doesn't have the ability to control the kernel
vt consoles.
Ray Strode