The new 'unique' API allows listing all unique field values that a field
specified by a field name can take in all entries of the journal. This
allows answering queries such as "What units logged to the journal?",
"What hosts have logged into the journal?", "Which boot IDs have logged
into the journal?".
Ultimately this allows implementation of tools similar to lastlog based
on journal data.
Note that listing these field values will not work for journal files
created with older journald, as the field values are not indexed in
older files.
Much like logind has a client in loginctl, and journald in journalctl
introduce timedatectl, to change the system time (incl. RTC), timezones
and related settings.
As audit is pretty much just a special kind of logging we should treat
it similar, and manage the audit fd in a static variable.
This simplifies the audit fd sharing with the SELinux access checking
code quite a bit.
a) Instead of parsing the bus messages inside of selinux-access.c
simply pass everything pre-parsed in the functions
b) implement the access checking with a macro that resolves to nothing
on non-selinux builds
c) split out the selinux checks into their own sources
selinux-util.[ch]
d) this unifies the job creation code behind the D-Bus calls
Manager.StartUnit() and Unit.Start().
Among other cleanups this introduces a threshold for the size of binary
blobs we serialize as integer arrays in the JSON output. THis can be
disabled via --all.
This requires a little bit of tip-toeing around to explicitly avoid
touching the environment from a sig handler. Instead, simply create a
function to reset the var to its "unset" state, allowing the next call
to columns() to recalculate and cache the new value.
Note: I did s/MANAGER/SYSTEMD/ everywhere, even though it makes the
patch quite verbose. Nevertheless, keeping MANAGER prefix in some
places, and SYSTEMD prefix in others would just lead to confusion down
the road. Better to rip off the band-aid now.
In many cases this might have a negative effect since we drop escaping
from strings where we better shouldn't have dropped it.
If unescaping makes sense for some settings we can readd it later again,
on a per-case basis.
https://bugs.freedesktop.org/show_bug.cgi?id=54522
When the new PID is invoked the journal socket from the initrd might
still be around. Due to the default log target being journal we'd log to
that initially when the new main systemd initializes even if the kernel
command line included a directive to redirect systemd's logging
elsewhere.
With this fix we initially always log to kmsg now, if we are PID1, and
only after parsing the kernel cmdline try to open the journal if that's
desired.
(The effective benefit of this is that SELinux performance data is now
logged again to kmsg like it used to be.)