Similar, refuse triggering deps on units that cannot trigger.
And rework how we ignore After= dependencies on device units, to work
the same way.
See: #14142
Build option "link-networkd-shared" to build a statically linked
systemd-networkd by using
-Dlink-udev-shared=false -Dlink-networkd-shared=false
on systems with full systemd stack except systemd-networkd, such
as RHEL/CentOS 8.
To make this easier to understand, let's always log (at debug level)
when we accept or reject each device:
/swapfile: detection of swap file offset on Btrfs is not supported
/swapfile: is a candidate device.
/dev/zram0: ignoring zram swap
/dev/vdb: ignoring device with lower priority
/dev/vdc: ignoring device with lower usable space
...
If we know that hibernation will fail, refuse. This includes cases where
/sys/power/resume is set and doesn't match any device, or
/sys/power/resume_offset is set and we're not on btrfs and it doesn't match.
If /sys/power/resume is not set at all, we still accept the device with the
highest priority (see 6d176522f5 and
88bc86fcf8)
Tested cases:
1. no swap active → refuse
2. just zram swap active → refuse
3. swapfile on btrfs with /sys/power/resume{,_offset} set → OK
4. swapfile on btrfs with /sys/power/resume set, offset not set → refuse
5. swapfile on btrfs with /sys/power/resume set to nonexistent device, offset set → refuse
6. /sys/power/resume not set, offset set, candidate exists → OK (*)
7. /sys/power/resume not set, offset not set, candidate exists → OK
(*) I think this should fail, but I'm leaving that for the next commit.
Change the behavior of string arrays in a bus property map. Previously,
passing the same strv pointer to more than one map entry would result in
the old strv being freed and overwritten. With this change, an existing
strv pointer is appended to.
This is important if we want to create one strv comprised of multiple
dependencies. This makes it so callers don't have to create one strv per
dependency and subsequently merge them into one strv.
Let's add the actual unicode names of the glyphs we use. Let's also add
in comments what the width expectations of these glyphs are on the
console.
Also, remove the "mdash" definition. First of all it wasn't used, but
what's worse the glyph encoded was actually an "ndash"...
Fixes: #14075
Previously, when first connecting to the bus after connecting to it we'd
issue a ListNames() bus call to the driver to figure out which bus names
are currently active. This information was then used to initialize the
initial state for services that use BusName=.
This change removes the whole code for this and replaces it with
something vastly simpler.
First of all, the ListNames() call was issues synchronosuly, which meant
if dbus was for some reason synchronously calling into PID1 for some
reason we'd deadlock. As it turns out there's now a good chance it does:
the nss-systemd userdb hookup means that any user dbus-daemon resolves
might result in a varlink call into PID 1, and dbus resolves quite a lot
of users while parsing its policy. My original goal was to fix this
deadlock.
But as it turns out we don't need the ListNames() call at all anymore,
since #12957 has been merged. That PR was supposed to fix a race where
asynchronous installation of bus matches would cause us missing the
initial owner of a bus name when a service is first started. It fixed it
(correctly) by enquiring with GetOwnerName() who currently owns the
name, right after installing the match. But this means whenever we start watching a bus name we anyway
issue a GetOwnerName() for it, and that means also when first connecting
to the bus we don't need to issue ListNames() anymore since that just
tells us the same info: which names are currently owned.
hence, let's drop ListNames() and instead make better use of the
GetOwnerName() result: if it failed the name is not owned.
Also, while we are at it, let's simplify the unit's owner_name_changed()
callback(): let's drop the "old_owner" argument. We never used that
besides logging, and it's hard to synthesize from just the return of a
GetOwnerName(), hence don't bother.
When a service unit watches a bus name (i.e. because of BusName= being
set), then we do two things: we install a match slot to watch how its
ownership changes, and we inquire about the current owner. Make sure we
always do both together or neither.
This in particular fixes a corner-case memleak when destroying bus
connections, since we never freed the GetNameOwner() bus slots when
destroying a bus when they were still ongoing.
Lennart Poettering
Yu Watanabe
Zbigniew Jędrzejewski-Szmek
ezst036
Robert Scheck
Kevin Kuehler
Frantisek Sumsal