sd_event_prepare() invokes callbacks that might drop the last user ref
on our event loop. Let's make sure we keep an explicit ref around it, so
that we won't end up with an invalid pointer. Similar in sd_event_run().
Basically, any function that is publically callable that might end up
invoking callbacks should ref the relevant objects to be protected
against callbacks destroying these objects while we still want to access
them. We did this correctly in sd_event_dispatch() and sd_event_loop(),
but these are not the only ones which are callable from the outside.
Commit 428a9f6f1d freed u->pids which is
problematic since the references to this unit in m->watch_pids were no more
removed when the unit was freed.
This patch makes sure to clean all this refs up before freeing u->pids by
calling unit_unwatch_all_pids().
This fixes the following warning:
```
parse_hwdb.py:120: UserWarning: warn_ungrouped_named_tokens_in_collection: setting results name 'SETTINGS*' on And expression collides with 'HZ' on contained expression
dpi_setting = (Optional('*')('DEFAULT') + INTEGER('DPI') + Suppress('@') + INTEGER('HZ'))('SETTINGS*')
```
Not sure about for the mount_matrix, but LGTM.com warns in that line,
and, adding Group() does not change the parse result.
This reverts the gist of da1921a5c3 and
0d9fca76bb (for ppc).
Quoting #17559:
> libseccomp 2.5 added socket syscall multiplexing on ppc64(el):
> https://github.com/seccomp/libseccomp/pull/229
>
> Like with i386, s390 and s390x this breaks socket argument filtering, so
> RestrictAddressFamilies doesn't work.
>
> This causes the unit test to fail:
> /* test_restrict_address_families */
> Operating on architecture: ppc
> Failed to install socket family rules for architecture ppc, skipping: Operation canceled
> Operating on architecture: ppc64
> Failed to add socket() rule for architecture ppc64, skipping: Invalid argument
> Operating on architecture: ppc64-le
> Failed to add socket() rule for architecture ppc64-le, skipping: Invalid argument
> Assertion 'fd < 0' failed at src/test/test-seccomp.c:424, function test_restrict_address_families(). Aborting.
>
> The socket filters can't be added so `socket(AF_UNIX, SOCK_DGRAM, 0);` still
> works, triggering the assertion.
Fixes#17559.
Only some small changes, because we updated recently. As usual, it seems that there are mostly
additions with a smaller amount of corrections, no big removals.
This test assumes capability_list_length() is an invalid cap number,
but that isn't true if the running kernel supports more caps than we were
compiled with, which results in the test failing.
Instead use cap_last_cap() + 1.
If cap_last_cap() is 63, there are no more 'invalid' cap numbers to test with,
so the invalid cap number test part is skipped.