1
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mirror of https://github.com/systemd/systemd-stable.git synced 2024-12-22 13:33:56 +03:00
systemd-stable/test
Daan De Meyer 2ecc7a5bca repart: Add roothash to output of all verity siblings
This can be used to match verity partitions together using the repart
JSON output.
2023-01-25 19:50:44 +00:00
..
dmidecode-dumps memory-id: Work-around incorrect "Number of slots" 2022-03-07 15:33:26 +00:00
fuzz journal: log filtering options support in PID1 2022-12-15 09:57:39 +00:00
hwdb.d
journal-data gitattributes: introduce and use "generated" attribute 2021-10-18 09:42:55 +02:00
knot-data tree-wide: replace "plural(s)" by "plurals" 2022-10-17 15:10:53 +02:00
TEST-01-BASIC test: make masking of supplementary services configurable 2022-06-19 11:27:41 +02:00
TEST-02-UNITTESTS test: ignore missing coverage in TEST-02 2022-04-07 12:45:13 +02:00
TEST-03-JOBS test: drop redundant IMAGE_NAME= 2022-06-10 12:31:14 +09:00
TEST-04-JOURNAL tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-05-RLIMITS tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-06-SELINUX TEST-06-SELINUX: add the usual spdx license header to policy files 2021-10-18 09:43:18 +02:00
TEST-07-ISSUE-1981 tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-08-ISSUE-2730 test: respect the global $QEMU_TIMEOUT 2022-08-26 19:16:45 +02:00
TEST-09-ISSUE-2691 test: respect the global $QEMU_TIMEOUT 2022-08-26 19:16:45 +02:00
TEST-10-ISSUE-2467 test: tweak TriggerLimitIntervalSec= when built with coverage 2021-10-25 11:02:22 +02:00
TEST-11-ISSUE-3166 test: respect the global $QEMU_TIMEOUT 2022-08-26 19:16:45 +02:00
TEST-12-ISSUE-3171 tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-13-NSPAWN-SMOKE test: suppress not-found errors for selinuxenabled 2022-09-02 22:09:29 +02:00
TEST-14-MACHINE-ID tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-15-DROPIN tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-16-EXTEND-TIMEOUT tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-17-UDEV test: respect the global $QEMU_TIMEOUT 2022-08-26 19:16:45 +02:00
TEST-18-FAILUREACTION test: respect the global $QEMU_TIMEOUT 2022-08-26 19:16:45 +02:00
TEST-19-DELEGATE test: respect the global $QEMU_TIMEOUT 2022-08-26 19:16:45 +02:00
TEST-20-MAINPIDGAMES tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-21-DFUZZER test: run TEST-21 in nspawn only if $TEST_PREFER_NSPAWN is set 2022-06-26 22:06:02 +02:00
TEST-22-TMPFILES tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-23-TYPE-EXEC tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-24-CRYPTSETUP test: store the key on a separate device 2022-05-26 15:06:41 +02:00
TEST-25-IMPORT tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-26-SYSTEMCTL Add basic systemctl edit test 2022-12-17 14:47:38 +01:00
TEST-27-STDOUTFILE tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-28-PERCENTJ-WANTEDBY tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-29-PORTABLE test: install losetup by default 2021-12-20 23:34:27 +09:00
TEST-30-ONCLOCKCHANGE tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-31-DEVICE-ENUMERATION test: respect the global $QEMU_TIMEOUT 2022-08-26 19:16:45 +02:00
TEST-32-OOMPOLICY tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-33-CLEAN-UNIT tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-34-DYNAMICUSERMIGRATE test: ignore gcov errors in TEST-34 2022-10-17 14:31:25 +02:00
TEST-35-LOGIN Revert "tests: add test for handling of background sessions" 2022-07-14 11:07:13 +02:00
TEST-36-NUMAPOLICY test: don't overwrite existing $QEMU_OPTIONS 2022-09-20 22:40:02 +02:00
TEST-37-RUNTIMEDIRECTORYPRESERVE tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-38-FREEZER tests: use !/usr/bin/env bash consistently 2021-10-18 09:04:45 +02:00
TEST-39-EXECRELOAD tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-40-EXEC-COMMAND-EX tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-41-ONESHOT-RESTART tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-42-EXECSTOPPOST tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-43-PRIVATEUSER-UNPRIV core: support ExtensionDirectories in user manager 2022-03-10 20:38:10 +00:00
TEST-44-LOG-NAMESPACE tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-45-TIMEDATE test: import timedated test from debian/ubuntu test suite 2022-06-10 16:04:52 +09:00
TEST-46-HOMED test: make homed test run in qemu 2021-11-16 12:33:44 +01:00
TEST-47-ISSUE-14566 tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-48-START-STOP-NO-RELOAD tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-49-RUNTIME-BIND-PATHS tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-50-DISSECT test: extend TEST-50-DISSECT for systemd-dissect --list and --with 2022-11-09 14:57:23 +01:00
TEST-51-ISSUE-16115 tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-52-HONORFIRSTSHUTDOWN test: check journal directly instead of capturing console output 2022-06-17 17:32:41 +02:00
TEST-53-ISSUE-16347 test: don't overwrite existing $QEMU_OPTIONS 2022-09-20 22:40:02 +02:00
TEST-54-CREDS tmpfiles: automatically provision /etc/issue.d/ + /etc/motd.d/ + /etc/hosts from credentials 2022-07-21 00:06:22 +02:00
TEST-55-OOMD core: ensure init.scope is realized after drop-ins have been loaded 2023-01-23 21:40:54 +01:00
TEST-56-EXIT-TYPE test: require unified cgroup hierarchy for TEST-56 2022-02-01 22:13:48 +01:00
TEST-57-ONSUCCESS-UPHOLD tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-58-REPART repart: support erofs 2022-12-10 11:26:36 +01:00
TEST-59-RELOADING-RESTART tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-60-MOUNT-RATELIMIT tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-61-UNITTESTS-QEMU tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-62-RESTRICT-IFACES tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-63-PATH test: make TEST-63 more reliable on slower machines 2022-08-25 16:21:39 +00:00
TEST-64-UDEV-STORAGE test: add coverage for the nvme-subsystem 2022-10-11 13:38:30 +02:00
TEST-65-ANALYZE tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-66-DEVICE-ISOLATION tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
TEST-67-INTEGRITY test: respect the global $QEMU_TIMEOUT 2022-08-26 19:16:45 +02:00
TEST-68-PROPAGATE-EXIT-STATUS tests: add test to cover service exit status propagation 2021-12-13 14:44:06 +00:00
TEST-69-SHUTDOWN test: use a dropin to override the end.service unit 2022-03-21 16:41:49 +01:00
TEST-70-TPM2 test: add simple integration test for checking PCR extension works as it should 2023-01-17 09:42:16 +01:00
TEST-71-HOSTNAME test: import hostnamed tests from debian/ubuntu test suite 2022-06-14 20:56:18 +09:00
TEST-72-SYSUPDATE test: add integration test for sysupdate 2022-03-19 00:13:55 +01:00
TEST-73-LOCALE test: import localed tests from debian/ubuntu test suite 2022-06-14 20:59:36 +09:00
TEST-74-AUX-UTILS test: introduce sanity coverage for auxiliary utils 2022-11-03 23:08:58 +01:00
TEST-75-RESOLVED test: mark knot.conf tmpfiles config as optional 2022-09-05 17:27:48 +02:00
TEST-76-SYSCTL sysctl: add --strict option to fail if sysctl does not exists 2022-07-25 10:15:43 +02:00
TEST-77-OPENFILE core: add OpenFile setting 2023-01-10 15:16:26 +01:00
test-bcd test: Add BCD unit test 2021-12-11 21:32:29 +01:00
test-execute tests: minor simplification in test-execute 2022-11-04 12:53:17 +01:00
test-fstab-generator test: store empty files rather than symlinks for test-fstab-generator 2022-01-09 18:17:40 +01:00
test-keymap-util test-keymap-util: always use kbd-model-map we ship 2021-11-02 16:48:55 +01:00
test-network network: assume prefix length is full address size 2023-01-19 22:09:10 +09:00
test-network-generator-conversion gitattributes: introduce and use "generated" attribute 2021-10-18 09:42:55 +02:00
test-path tests: add spdx license header to test unit/link/network/conf files 2021-10-18 09:04:45 +02:00
test-path-util tests: add spdx headers to scripts and Makefiles 2021-10-18 09:04:45 +02:00
test-resolve resolved: Test for DnsStream (plain TCP DNS and DoT) 2022-01-27 14:33:56 +09:00
test-sysusers test-sysusers: check group creation with matching user entry 2022-11-03 15:12:15 +00:00
test-umount gitattributes: introduce and use "generated" attribute 2021-10-18 09:42:55 +02:00
testsuite-03.units job: Don't discard propagated restart jobs when unit is activating 2022-08-25 16:38:23 -07:00
testsuite-04.units journal: add integration tests for log filtering 2022-12-15 09:57:39 +00:00
testsuite-06.units tests: add spdx license header to test unit/link/network/conf files 2021-10-18 09:04:45 +02:00
testsuite-08.units TEST-08: don't force ext4 for / 2021-11-16 16:58:49 +01:00
testsuite-10.units tests: add spdx license header to test unit/link/network/conf files 2021-10-18 09:04:45 +02:00
testsuite-11.units tests: add spdx license header to test unit/link/network/conf files 2021-10-18 09:04:45 +02:00
testsuite-16.units tests: add spdx license header to test unit/link/network/conf files 2021-10-18 09:04:45 +02:00
testsuite-28.units tests: add spdx license header to test unit/link/network/conf files 2021-10-18 09:04:45 +02:00
testsuite-30.units/systemd-timedated.service.d tests: add spdx license header to test unit/link/network/conf files 2021-10-18 09:04:45 +02:00
testsuite-52.units tests: add spdx license header to test unit/link/network/conf files 2021-10-18 09:04:45 +02:00
testsuite-63.units test: make TEST-63 more reliable on slower machines 2022-08-25 16:21:39 +00:00
units repart: Add roothash to output of all verity siblings 2023-01-25 19:50:44 +00:00
.gitignore
create-busybox-container tests: add nspawn's rootidmap integration test 2022-10-17 12:01:50 +02:00
create-sys-script.py license: LGPL-2.1+ -> LGPL-2.1-or-later 2020-11-09 13:23:58 +09:00
hwdb-test.sh hwdb-test: don't rely on --root= quirk 2022-08-22 14:07:45 +02:00
meson.build tests: add a simple test that bootctl output is valid json 2022-12-01 18:01:00 +01:00
mkosi-check-and-shutdown.service ci: check for failed services after boot 2021-12-10 10:25:43 +01:00
mkosi-check-and-shutdown.sh ci: check for failed services after boot 2021-12-10 10:25:43 +01:00
mkosi.build.networkd-test licensing: add forgotten spdx headers 2021-10-01 14:45:00 +02:00
mkosi.default.networkd-test mkosi: Remove usage of deprecated option names/sections 2022-07-18 16:54:58 +02:00
mkosi.nspawn.networkd-test licensing: add forgotten spdx headers 2021-10-01 14:45:00 +02:00
networkd-test.py network: Show network and link file dropins in networkctl status 2023-01-12 13:44:52 +09:00
README.testsuite test: update Ubuntu CI docs 2023-01-19 13:54:31 +01:00
rule-syntax-check.py test: drop unused modules 2022-10-13 17:34:11 +09:00
run-integration-tests.sh test runner: print time before/after tests 2021-11-22 09:05:00 +00:00
run-unit-tests.py licensing: add forgotten spdx headers 2021-10-01 14:45:00 +02:00
sd-script.py test: introduce __eq__() and __ne__() 2022-10-13 17:41:48 +09:00
sys-script.py Merge pull request #17431 from msekletar/udev-link-update-race 2020-11-10 09:41:57 +01:00
sysv-generator-test.py license: LGPL-2.1+ -> LGPL-2.1-or-later 2020-11-09 13:23:58 +09:00
test-bootctl-json.sh tests: add a simple test that bootctl output is valid json 2022-12-01 18:01:00 +01:00
test-compare-versions.sh analyze: use '' instead of the empty string when showing versions 2022-05-25 16:01:14 +02:00
test-exec-deserialization.py test: call sync() before checking the test logs 2022-10-17 20:24:24 +00:00
test-fstab-generator.sh test: fstab-generator: adjust PATH for fsck 2022-11-04 23:40:50 +01:00
test-functions test: bump the client-side timeout in sd-bus as well 2023-01-23 18:44:55 +01:00
test-network-generator-conversion.sh licensing: add forgotten spdx headers 2021-10-01 14:45:00 +02:00
test-rpm-macros.sh tree-wide: drop manually-crafted message for missing variables 2022-05-04 20:53:46 +09:00
test-shutdown.py test: bump the container spawn timeout to 60s 2023-01-23 19:13:49 +01:00
test-systemctl-enable.sh Revert "shared/install: create relative symlinks for enablement and aliasing" 2022-05-05 19:02:26 +02:00
test-systemd-tmpfiles.py test/test-systemd-tmpfiles.py: do not fail if machine-id is missing 2022-10-25 16:00:26 +01:00
test-sysusers.sh.in sysusers: use log_syntax (changes prefix from '[%s:%u]' to '%s:%u:') 2022-08-22 12:52:25 +02:00
testdata test: convert TEST-35-NETWORK-GENERATOR into a unit test 2020-03-28 11:46:48 +01:00
udev-dmi-memory-id-test.sh test: shellcheck-ify test scripts 2021-09-30 12:12:00 +02:00
udev-test.pl test-udev: add a brief test for -= operator for SYMLINK 2023-01-17 14:39:42 +09:00

The extended testsuite only works with UID=0. It consists of the subdirectories
named "test/TEST-??-*", each of which contains a description of an OS image and
a test which consists of systemd units and scripts to execute in this image.
The same image is used for execution under `systemd-nspawn` and `qemu`.

To run the extended testsuite do the following:

$ ninja -C build  # Avoid building anything as root later
$ sudo test/run-integration-tests.sh
ninja: Entering directory `/home/zbyszek/src/systemd/build'
ninja: no work to do.
--x-- Running TEST-01-BASIC --x--
+ make -C TEST-01-BASIC clean setup run
make: Entering directory '/home/zbyszek/src/systemd/test/TEST-01-BASIC'
TEST-01-BASIC CLEANUP: Basic systemd setup
TEST-01-BASIC SETUP: Basic systemd setup
...
TEST-01-BASIC RUN: Basic systemd setup [OK]
make: Leaving directory '/home/zbyszek/src/systemd/test/TEST-01-BASIC'
--x-- Result of TEST-01-BASIC: 0 --x--
--x-- Running TEST-02-CRYPTSETUP --x--
+ make -C TEST-02-CRYPTSETUP clean setup run

If one of the tests fails, then $subdir/test.log contains the log file of
the test.

To run just one of the cases:

$ sudo make -C test/TEST-01-BASIC clean setup run

Specifying the build directory
==============================

If the build directory is not detected automatically, it can be specified
with BUILD_DIR=:

$ sudo BUILD_DIR=some-other-build/ test/run-integration-tests

or

$ sudo make -C test/TEST-01-BASIC BUILD_DIR=../../some-other-build/ ...

Note that in the second case, the path is relative to the test case directory.
An absolute path may also be used in both cases.

Testing installed binaries instead of built
===========================================

To run the extended testsuite using the systemd installed on the system instead
of the systemd from a build, use the NO_BUILD=1:

$ sudo NO_BUILD=1 test/run-integration-tests

Configuration variables
=======================

TEST_NO_QEMU=1
    Don't run tests under qemu

TEST_QEMU_ONLY=1
    Run only tests that require qemu

TEST_NO_NSPAWN=1
    Don't run tests under systemd-nspawn

TEST_PREFER_NSPAWN=1
    Run all tests that do not require qemu under systemd-nspawn

TEST_NO_KVM=1
    Disable qemu KVM auto-detection (may be necessary when you're trying to run the
    *vanilla* qemu and have both qemu and qemu-kvm installed)

TEST_NESTED_KVM=1
    Allow tests to run with nested KVM. By default, the testsuite disables
    nested KVM if the host machine already runs under KVM. Setting this
    variable disables such checks

QEMU_MEM=512M
    Configure amount of memory for qemu VMs (defaults to 512M)

QEMU_SMP=1
    Configure number of CPUs for qemu VMs (defaults to 1)

KERNEL_APPEND='...'
    Append additional parameters to the kernel command line

NSPAWN_ARGUMENTS='...'
    Specify additional arguments for systemd-nspawn

QEMU_TIMEOUT=infinity
    Set a timeout for tests under qemu (defaults to 1800 sec)

NSPAWN_TIMEOUT=infinity
    Set a timeout for tests under systemd-nspawn (defaults to 1800 sec)

INTERACTIVE_DEBUG=1
    Configure the machine to be more *user-friendly* for interactive debuggung
    (e.g. by setting a usable default terminal, suppressing the shutdown after
    the test, etc.)

The kernel and initrd can be specified with $KERNEL_BIN and $INITRD. (Fedora's
or Debian's default kernel path and initrd are used by default)

A script will try to find your qemu binary. If you want to specify a different
one with $QEMU_BIN.

Debugging the qemu image
========================

If you want to log in the testsuite virtual machine, you can specify additional
kernel command line parameter with $KERNEL_APPEND and then log in as root.

$ sudo make -C test/TEST-01-BASIC KERNEL_APPEND="systemd.unit=multi-user.target" run

Root password is empty.

Ubuntu CI
=========

New PR submitted to the project are run through regression tests, and one set
of those is the 'autopkgtest' runs for several different architectures, called
'Ubuntu CI'.  Part of that testing is to run all these tests.  Sometimes these
tests are temporarily deny-listed from running in the 'autopkgtest' tests while
debugging a flaky test; that is done by creating a file in the test directory
named 'deny-list-ubuntu-ci', for example to prevent the TEST-01-BASIC test from
running in the 'autopkgtest' runs, create the file
'TEST-01-BASIC/deny-list-ubuntu-ci'.

The tests may be disabled only for specific archs, by creating a deny-list file
with the arch name at the end, e.g.
'TEST-01-BASIC/deny-list-ubuntu-ci-arm64' to disable the TEST-01-BASIC test
only on test runs for the 'arm64' architecture.

Note the arch naming is not from 'uname -m', it is Debian arch names:
https://wiki.debian.org/ArchitectureSpecificsMemo

For PRs that fix a currently deny-listed test, the PR should include removal
of the deny-list file.

In case a test fails, the full set of artifacts, including the journal of the
failed run, can be downloaded from the artifacts.tar.gz archive which will be
reachable in the same URL parent directory as the logs.gz that gets linked on
the Github CI status.

To add new dependencies or new binaries to the packages used during the tests,
a merge request can be sent to: https://salsa.debian.org/systemd-team/systemd
targeting the 'upstream-ci' branch.

The cloud-side infrastructure, that is hooked into the Github interface, is
located at:

https://git.launchpad.net/autopkgtest-cloud/

In case of infrastructure issues with this CI, things might go wrong in two
places:

- starting a job: this is done via a Github webhook, so check if the HTTP POST
  are failing on https://github.com/systemd/systemd/settings/hooks
- running a job: all currently running jobs are listed at
  https://autopkgtest.ubuntu.com/running#pkg-systemd-upstream in case the PR
  does not show the status for some reason
- reporting the job result: this is done on Canonical's cloud infrastructure,
  if jobs are started and running but no status is visible on the PR, then it is
  likely that reporting back is not working

For infrastructure help, reaching out to Canonical via the #ubuntu-devel channel
on libera.chat is an effective way to receive support in general.

Manually running a part of the Ubuntu CI test suite
===================================================

In some situations one may want/need to run one of the tests run by Ubuntu CI
locally for debugging purposes. For this, you need a machine (or a VM) with
the same Ubuntu release as is used by Ubuntu CI (Jammy ATTOW).

First of all, clone the Debian systemd repository and sync it with the code of
the PR (set by the $UPSTREAM_PULL_REQUEST env variable) you'd like to debug:

# git clone https://salsa.debian.org/systemd-team/systemd.git
# cd systemd
# git checkout upstream-ci
# TEST_UPSTREAM=1 UPSTREAM_PULL_REQUEST=12345 ./debian/extra/checkout-upstream

Now install necessary build & test dependencies:

## PPA with some newer Ubuntu packages required by upstream systemd
# add-apt-repository -y ppa:upstream-systemd-ci/systemd-ci
# apt build-dep -y systemd
# apt install -y autopkgtest debhelper genisoimage git qemu-system-x86

Build systemd deb packages with debug info:

# TEST_UPSTREAM=1 DEB_BUILD_OPTIONS="nocheck nostrip" dpkg-buildpackage -us -uc
# cd ..

Prepare a testbed image for autopkgtest (tweak the release as necessary):

# autopkgtest-buildvm-ubuntu-cloud --ram-size 1024 -v -a amd64 -r jammy

And finally run the autopkgtest itself:

# autopkgtest -o logs *.deb systemd/ \
              --timeout-factor=3 \
              --test-name=boot-and-services \
              --shell-fail \
              -- autopkgtest-virt-qemu --ram-size 2048 autopkgtest-jammy-amd64.img

where --test-name= is the name of the test you want to run/debug. The
--shell-fail option will pause the execution in case the test fails and shows
you the information how to connect to the testbed for further debugging.

Manually running CodeQL analysis
=====================================

This is mostly useful for debugging various CodeQL quirks.

Download the CodeQL Bundle from https://github.com/github/codeql-action/releases
and unpack it somewhere. From now the 'tutorial' assumes you have the `codeql`
binary from the unpacked archive in $PATH for brevity.

Switch to the systemd repository if not already:

$ cd <systemd-repo>

Create an initial CodeQL database:

$ CCACHE_DISABLE=1 codeql database create codeqldb --language=cpp -vvv

Disabling ccache is important, otherwise you might see CodeQL complaining:

No source code was seen and extracted to /home/mrc0mmand/repos/@ci-incubator/systemd/codeqldb.
This can occur if the specified build commands failed to compile or process any code.
 - Confirm that there is some source code for the specified language in the project.
 - For codebases written in Go, JavaScript, TypeScript, and Python, do not specify
   an explicit --command.
 - For other languages, the --command must specify a "clean" build which compiles
   all the source code files without reusing existing build artefacts.

If you want to run all queries systemd uses in CodeQL, run:

$ codeql database analyze codeqldb/ --format csv --output results.csv .github/codeql-custom.qls .github/codeql-queries/*.ql -vvv

Note: this will take a while.

If you're interested in a specific check, the easiest way (without hunting down
the specific CodeQL query file) is to create a custom query suite. For example:

$ cat >test.qls <<EOF
- queries: .
  from: codeql/cpp-queries
- include:
    id:
        - cpp/missing-return
EOF

And then execute it in the same way as above:

$ codeql database analyze codeqldb/ --format csv --output results.csv test.qls -vvv

More about query suites here: https://codeql.github.com/docs/codeql-cli/creating-codeql-query-suites/

The results are then located in the `results.csv` file as a comma separated
values list (obviously), which is the most human-friendly output format the
CodeQL utility provides (so far).