rearrange_stdio() invalidates specified fds even on failure, which means
we should always invalidate the fds we pass in no matter what. Let's
make this explicit by using TAKE_FD() for that everywhere.
Note that in many places we such invalidation doesnt get us much
behaviour-wise, since we don't use the variables anymore later. But
TAKE_FD() in a way is also documentation, it encodes explicitly that the
fds are invalidated here, so I think it's a good thing to always make
this explicit here.
It is only added in the one place where we actually try to set the
setting to a new value. Before we were testing if we can set to it the
existing value, which was a noop. We could still get a permission error,
but this is the first place where we would propagate EROFS.
From packit/rawhide-arm64 logs:
Assertion 'limit >= INT_MAX || get_process_ppid(limit+1, NULL) == -ESRCH' failed at src/test/test-process-util.c:855, function test_get_process_ppid(). Aborting.
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The kernel has a few different limits. In particular kernel.threads-max can be
set to some lower value, and kernel.pid_max can be set to a higher value. This
is nice because it reduces PID reuse, even if the number of threads that is
allowed is limited. But the tests assumed that we cannot have a thread with
PID above MIN(kernel.threads-max, kernel.pid_max-1), which is not valid.
So let's rework the whole thing: let's expose the helpers to read
kernel.threads-max and kernel.pid_max, and print what they return in tests.
procfs_tasks_get_limit() was something that is only used in tests, and wasn't
very well defined, so let's drop it.
Fixes#21193.
This test makes assumptions on the availability of some mappings contained in
kbd-model-map and therefore strongly relies on the version shipped by
upstream. IOW the test is likely to fail if it's installed on a system with a
more comprehensive kbd-model-map.
This patch makes the upstream kbd-model-map file available via a symlink in
test/testdata/test-keymap-util dir and makes sure that this specific version is
always used by test-keymap-util regardless of whether the test is installed and
run on a different system or directly run (optionally via meson) from the
project working dir.
Let's document this for now. We should be able to lift these limitations
sooner or later, at which point we can drop this documentation again.
These two limitations are a pitfall that people should be aware of,
before going FIDO2-only.
See: #20230#19208
