@markj I am thinking of loading snd_dummy.ko (see D45967) to use as a test device, however I am not really sure what is the suggested way of loading and unloading a kernel module in ATF script. I can (un-)load it for every test case, but I am not sure if that the correct way to do it.

christos added a parent revision: D45973: mixer(8): Make mute and recsrc argument parsing more robust.Jul 14 2024, 5:21 PM

however I am not really sure what is the suggested way of loading and unloading a kernel module in ATF script.

It's ok to simply load it at the beginning of each test. Something like if ! kldload -n snd_dummy; then atf_skip ...

usr.sbin/mixer/tests/mixer_test.sh
33	if ! mixer >/dev/null 2>&1; then atf_skip ... fi
43	What is this `atf_pass` doing?
160	What does it mean to "test muting"? Does this verify that the kernel driver received some command to mute a device?
223	`mixer` exits with status 0 in these cases?

christos added inline comments.Jul 22 2024, 11:16 AM

usr.sbin/mixer/tests/mixer_test.sh
43	It fails in case the mixer does not exist (could also call `mixer_exists()`), so that we do not execute the command right after it.
160	It checks both if the driver actually responds to (un-)mute commands, and also whether mixer(8)'s argument parsing is correct.
223	Yes.

Any comments?

Load snd_dummy in each test.

Harbormaster completed remote builds in B58800: Diff 141311.Jul 24 2024, 3:33 PM

Shouldn't we select the snd_dummy device for our mixer tests?
Current default could be set to any device, with not all features available that we want to test. Or am I missing something?

In D45974#1051370, @dev_submerge.ch wrote:

Shouldn't we select the snd_dummy device for our mixer tests?
Current default could be set to any device, with not all features available that we want to test. Or am I missing something?

Yes, it would be more robust in case there is more than 1 card attached. I will update the diff shortly.

Introduce set_default() and restore_default() to set the dummy device as the
default one during tests, and restore the default device on cleanup.

Harbormaster completed remote builds in B58828: Diff 141381.Jul 25 2024, 3:41 PM

dev_submerge.ch accepted this revision.Jul 26 2024, 2:10 PM

This revision is now accepted and ready to land.Jul 26 2024, 2:10 PM

Closed by commit rG94a86f3f6920: mixer(8): Add tests (authored by christos). · Explain WhyJul 27 2024, 11:58 AM

This revision was automatically updated to reflect the committed changes.

christos added a commit: rG94a86f3f6920: mixer(8): Add tests.

lwhsu added a subscriber: lwhsu.Jul 27 2024, 6:47 PM

lwhsu added inline comments.

usr.sbin/mixer/Makefile
9	FYI since the tests are newly (re)added, we also need to modify `etc/mtree/BSD.tests.dist` to create `/usr/tests/usr.sbin/mixer` I added it in rG21e98f6d195a5db63b17025f339684048834e1aa