We go through the whole file system, so this test can take arbitrary time. But
this test is still quite useful, so let's at least try to make it more efficent
by not descending at all into the directories we would filter out later on
anyway.
Also increase the timeout, in case the previous step doesn't help enough.
Absolute paths make everything simple and quick, but sometimes this requirement
can be annoying. A good example is calling 'test', which will be located in
/usr/bin/ or /bin depending on the distro. The need the provide the full path
makes it harder a portable unit file in such cases.
This patch uses a fixed search path (DEFAULT_PATH which was already used as the
default value of $PATH), and if a non-absolute file name is found, it is
immediately resolved to a full path using this search path when the unit is
loaded. After that, everything behaves as if an absolute path was specified. In
particular, the executable must exist when the unit is loaded.
It's always visible:
$ sudo modprobe sit
$ sudo unshare -n ip l
1: lo: <LOOPBACK> mtu 65536 qdisc noop state DOWN mode DEFAULT group default qlen 1000
...
2: sit0@NONE: <NOARP> mtu 1480 qdisc noop state DOWN mode DEFAULT group default qlen 1000
...
grep already indicates if it matched anything by return value.
Additional advantage is then that if the test fails, the unexpected
matching lines are visible in the log output.
Also fix one case where the presence of a newline was used to generate
an invalid environment assignment.
Tested: with mkosi, which builds the local tree and run ninja tests.
The unit files for test-execute are named like
`exec-(setting-name-in-lower-character)-(optional-text).service`.
However, test units for AmbientCapabilities= are not following this.
So, let's rename them for the consistency.
This does not change anything in the functionality of the test.
The nobody user/group may not synthesized by systemd.
To run tests the functionalities in such situation, this adds tests
by user/group by daemon, as it is expected to exists all environments.
We currently look for "nobody" and "nfsnobody" when testing groups, both
of which do not exist on Ubuntu, our main testing environment. Let's
extend the tests slightly to also use "nogroup" if it exists.
