For some reason, systemd-logind is trying to handle idle action in one of my containers:
Jun 07 10:28:08 rawhide systemd-logind[42]: System idle. Taking action.
Jun 07 10:28:08 rawhide systemd-logind[42]: Requested operation not supported, ignoring.
But we didn't log what exactly was being done. Let's put the name of the action in messages.
All callers pass either a fixed action, or HANDLE_IGNORE is explicitly filtered
out. Let's remove this case here, because we cannot properly log what opreation
we are ignoring.
Previously, logind's logind-session.h would define prototypes for
logind-session.c and logind-session-dbus.c. Split that out, so that
there's a separate logind-session-dbus.h for that. Similar for seats and
users as well as the manager itself.
This changes no code, just rearranges where protoypes are located.
Most of the operations one can do on sessions so far accepted an empty
session name as a shortcut for the caller's session. This is quite
useful traditionally, but much less useful than it used to be, since
most user code now (rightfully) runs in --user context, not in a
session.
With this change we tweak the logic a bit: we introduce the two special
session and seat names "self" and "auto". The former refers to the
session/seat the client is in, and is hence mostly equivalent to te
empty string "" as before. However, the latter refers to the
session/seat the client is in if that exists, with a fallback of the
user's display session if not. Clients can hence reference "auto"
instead of the empty string if they really don't want to think much
about sessions.
Why "self" btw? Previously, we'd already expose a special dbus object
with the path /org/freedesktop/login1/session/self (and similar for the
seat), matching what the empty string did for bus calls that took a
session name. With this scheme we reuse this identifier and introduce
"auto" in a similar way.
Of course this means real-life seats and sessions can never be named
"self" or "auto", but they aren't anyway: valid seat names have to start
with "seat" anyway, and sessions are generated server-side as either a
numeric value or "c" suffixed with a counter ID.
Fixes: #12399
Interestingly, elect_display_compare() already ordered "user" sessions
before "greeter" sessions, though nothing other than "user" sessions
where ever considered anyway.
Fixes: #12399
This augments the drm/input device management by adding a single method
call for setting the brightness of an "leds" or "backlight" kernel class
device.
This method call requires no privileges to call, but a caller can only
change the brightness on sessions that are currently active, and they
must own the session.
This does not do enumeration of such class devices, feature or range
probing, chnage notification; it doesn't help associating graphics or
input devices with their backlight or leds devices. For all that clients
should go directly to udev/sysfs. The SetBrightness() call is just for
executing the actual change operation, that is otherwise privileged.
Example line:
busctl call org.freedesktop.login1 /org/freedesktop/login1/session/self org.freedesktop.login1.Session SetBrightness ssu "backlight" "intel_backlight" 200
The parameter the SetBrightness() call takes are the kernel subsystem
(i.e. "leds" or "backlight"), the device name, and the brightness
value.
On some hw setting the brightness is slow, and implementation and write
access to the sysfs knobs exposes this slowness. Due to this we'll fork
off a writer process in the background so that logind doesn't have to
block. Moreover, write requestes are coalesced: when a write request is
enqueued while one is already being executed it is queued. When another
write reques is then enqueued the earlier one is replaced by the newer
one, so that only one queued write request per device remains at any
time. Method replies are sent as soon as the first write request that
happens after the request was received is completed.
It is recommended that bus clients turn off the "expect_reply" flag on
the dbus messages they send though, that relieves logind from sending
completion notification and is particularly a good idea if clients
implement reactive UI sliders that send a quick secession of write
requests.
Replaces: #12413
These devices do not become user-accessible this way, but they are
logically assigned to a seat, which makes a lot of sense, since they are
human-facing output devices, and such should belong to one.
When emitting the calendarspec warning we want to see some color.
Follow-up for 04220fda5c.
Exceptions:
- systemctl, because it has a lot hand-crafted coloring
- tmpfiles, sysusers, stdio-bridge, etc, because they are also used in
services and I'm not sure if this wouldn't mess up something.
This is partially a refactoring, but also makes many more places use
unlocked operations implicitly, i.e. all users of fopen_temporary().
AFAICT, the uses are always for short-lived files which are not shared
externally, and are just used within the same context. Locking is not
necessary.
let's use sd_notifyf(). Let's also stop validating the session ID here.
This is the destructor. if it contains a dash, we are already too late
here anyway.
Let's be helpful to static analyzers which care about whether we
knowingly ignore return values. We do in these cases, since they are
usually part of error paths.
This adds support for user to set & get reboot parameter for reboot.
As callee would be next issuing Reboot call same policy checks are being used.
If unit file issuing the reboot action defines RebootArgument (or similar) that
setting takes precedence.
