This is primarily useful for services that need to track clients which
reference certain objects they maintain, or which explicitly want to
subscribe to certain events. Something like this is done in a large
number of services, and not trivial to do. Hence, let's unify this at
one place.
This also ports over PID 1 to use this to ensure that subscriptions to
job and manager events are correctly tracked. As a side-effect this
makes sure we properly serialize and restore the track list across
daemon reexec/reload, which didn't work correctly before.
This also simplifies how we distribute messages to broadcast to the
direct busses: we only track subscriptions for the API bus and
implicitly assume that all direct busses are subscribed. This should be
a pretty OK simplification since clients connected via direct bus
connections are shortlived anyway.
Previously the returned object of constructor functions where sometimes
returned as last, sometimes as first and sometimes as second parameter.
Let's clean this up a bit. Here are the new rules:
1. The object the new object is derived from is put first, if there is any
2. The object we are creating will be returned in the next arguments
3. This is followed by any additional arguments
Rationale:
For functions that operate on an object we always put that object first.
Constructors should probably not be too different in this regard. Also,
if the additional parameters might want to use varargs which suggests to
put them last.
Note that this new scheme only applies to constructor functions, not to
all other functions. We do give a lot of freedom for those.
Note that this commit only changes the order of the new functions we
added, for old ones we accept the wrong order and leave it like that.
In some cases it is interesting to map a PID to two units at the same
time. For example, when a user logs in via a getty, which is reexeced to
/sbin/login that binary will be explicitly referenced as main pid of the
getty service, as well as implicitly referenced as part of the session
scope.
When a process dies that we can associate with a specific unit, start
watching all other processes of that unit, so that we can associate
those processes with the unit too.
Also, for service units start doing this as soon as we get the first
SIGCHLD for either control or main process, so that we can follow the
processes of the service from one to the other, as long as process that
remain are processes of the ones we watched that died and got reassigned
to us as parent.
Similar, for scope units start doing this as soon as the scope
controller abandons the unit, and thus management entirely reverts to
systemd. To abandon a unit introduce a new Abandon() scope unit method
call.
This reverts commit 28c758de94
but makes job_coldplug smarter.
In (v1) I changed the job start timestamp to be always set, so the
start time can be reported in the cylon eye message. The bug was that
when deserializing jobs, they would be ignored if their start
timestamp was unset which was synonymous with no timeout. But after
the change, jobs would have a start timestamp set despite having no
timeout. After deserialization they would be considered immediately
expired. Fix this by checking if the timeout is not zero when
considering jobs for expiration.
When set to auto, status will shown when the first ephemeral message
is shown (a job has been running for five seconds). Then until the
boot or shutdown ends, status messages will be shown.
No indication about the switch is done: I think it should be clear
for the user that first the cylon eye and the ephemeral messages appear,
and afterwards messages are displayed.
The initial arming of the event source was still wrong, but now should
really be fixed.
It would fire just once.
Also fix units from sec to usec as appropriate.
Decrease the switching interval to 1/3 s, so that when the time
remaining is displayed with 1s precision, it doesn't jump by 2s every
once in a while. Also, the system is feels noticably faster when the
status changes couple of times per second instead of every few
seconds.
Produces output like:
[ *** ] (1 of 2) A start job is running for slow.service (33s / 1min 30s)
The first nubmer is the time since job start, the second is the job timeout.
It is nicer to predefine patterns using configure time check instead of
using casts everywhere.
Since we do not need to use any flags, include "%" in the format instead
of excluding it like PRI* macros.
Information about signals which are not routinely received by systemd
are printed at info level. This should make it easier to see what is
happening in the system.
The only problem is that libgen.h #defines basename to point to it's
own broken implementation instead of the GNU one. This can be fixed
by #undefining basename.
Since we want to retain the ability to break kernel ←→ userspace ABI
after the next release, let's not make use by default of kdbus, so that
people with future kernels will not suddenly break with current systemd
versions.
kdbus support is left in all builds but must now be explicitly requested
at runtime (for example via setting $DBUS_SESSION_BUS). Via a configure
switch the old behaviour can be restored. In fact, we change autogen.sh
to do this, so that git builds (which run autogen.sh) get kdbus by
default, but tarball builds (which ue the configure defaults) do not get
it, and hence this stays out of the distros by default.
This way, we can avoid executing two /bin/swapon jobs to be dispatched
for the same swap device if it is configured for two different paths.
Previously we were just tracking the device nodes of active swap
devices, which would not allow us to recognize the identity of two swap
devices before they are active.
https://bugs.freedesktop.org/show_bug.cgi?id=69835
Given that plymouth listens on an abstract namespace socket and if
CLONE_NEWNET is not used the abstract namespace is shared with the host
we might actually end up send plymouth data to the host.
This patch converts PID 1 to libsystemd-bus and thus drops the
dependency on libdbus. The only remaining code using libdbus is a test
case that validates our bus marshalling against libdbus' marshalling,
and this dependency can be turned off.
This patch also adds a couple of things to libsystem-bus, that are
necessary to make the port work:
- Synthesizing of "Disconnected" messages when bus connections are
severed.
- Support for attaching multiple vtables for the same interface on the
same path.
This patch also fixes the SetDefaultTarget() and GetDefaultTarget() bus
calls which used an inappropriate signature.
As a side effect we will now generate PropertiesChanged messages which
carry property contents, rather than just invalidation information.
