While we don't build these by default, all the source files still
get added to the compile_commands.json file by meson, which can confuse
tools as they might end up analyzing the source files twice or analyzing
the wrong one.
To avoid this issue, only define the static library target if the
corresponding option is enabled.
meson by default adds the current source and build directory as include
directories. Because we structure our meson code by gathering a giant dict
of everything we want to do and then doing all the actual target generation
in the top level meson.build, this behavior does not make sense at all because
we end up adding the top level repository directory as an include directory
which is never what we want.
At the same time, let's also make sure the top level directory of the build
directory is not an include directory, by moving the version.h generation
into the src/version subdirectory and then adding the src/version subdirectory
of the build directory as an include directory instead of the top level
repository directory.
Making this change means that language servers such as clangd can't get
confused when they automatically insert an #include line and insert
"#include "src/basic/fs-util.h" instead of "#include "fs-util.h".
Currently, when we want to add unit tests for code that is compiled into
an executable, we either compile the code at least twice (once for the
executable, and once for each test that uses it) or we create a static
library which is then used by both the executable and all the tests.
Both of these options are not ideal, compiling source files more than
once slows down the build for no reason and creating the intermediate
static libraries takes a lot of boilerplate.
Instead, let's use the extract_objects() method that meson exposes on
build targets. This allows us to extract the objects corresponding to
specific source files and use them in other executables. Because we
define all executables upfront into a dictionary, we integrate this into
the dictionary approach by adding two new fields:
- 'extract' takes a list of files for which objects should be extracted.
The extracted objects are stored in a dict keyed by the executable name
from which they were extracted.
- 'objects' takes the name of an executable from which the extracted
objects should be added to the current executable.
One side effect of this approach is that we can't build test executables
anymore without building the main executable, so we stop building test
executables unless we're also building the main executable. This allows
us to switch to using subdir_done() in all of these subdirectories to skip
parsing them if the corresponding component is disabled.
These changes get me down from 2439 => 2403 ninja targets on a full rebuild
from scratch.
Currently, when fuzzers are enabled, we run meson from within meson
to build the fuzzer executables with sanitizers. The idea is that
we can build the fuzzers with different kinds of sanitizers
independently from the main build.
The issue with this setup is that we don't actually make use of it.
We only build the fuzzers with one set of sanitizers (address,undefined)
so we're adding a bunch of extra complexity without any benefit as we
can just setup the top level meson build with these sanitizers and get
the same result.
The other issue with this setup is that we don't pass on all the options
passed to the top level meson build to the nested meson build. The only things
we pass on are extra compiler arguments and the value of the auto_features
option, but none of the individual feature options if overridden are passed on,
which can lead to very hard to debug issues as an option enabled in the top
level build is not enabled in the nested build.
Since we're not getting anything useful out of this setup, let's simplify
and get rid of the nested meson build. Instead, sanitizers should be enabled
for the top level meson.build. This currently didn't work as we were overriding
the sanitizers passed to the meson build with the fuzzer sanitizer, so we
fix that as well by making sure we combine the fuzzer sanitizer with the ones
passed in by the user.
We also drop support for looking up libFuzzer as a separate library as
it has been shipped builtin in clang since clang 6.0, so we can assume
that -fsanitize=fuzzer is available.
To make sure we still run the fuzzing tests, we enable the fuzz-tests option
by default now to make sure they still always run (without instrumentation unless
one of llvm-fuzz or oss-fuzz is enabled).
meson's target has a few issues:
- Runs on all source files regardless if they're included in the
build or not
- Doesn't have any dependencies on generated sources which means we
have to do a full build first before we can run clang-tidy
- Doesn't allow us to pass any extra arguments
To work around these, let's define our own clang-tidy target instead
using llvm's run-clang-tidy script. Alongside the clang-tidy target,
let's start keeping track of all generated sources which we make the
clang-tidy target depend on. We also add a new target which will only
generate source files which is useful for setting up the source tree
for running code analysis against it.
Even though these are in our tree, we should still treat them as
system includes which helps various tools (clangd, iwyu, ...) understand
that these are system includes and <> should be used instead of "".
We add a default test setup that excludes the integration-tests suite
so that the integration tests don't run by default. This allows us to
get rid of $SYSTEMD_INTEGRATION_TESTS. Then, we add two extra setups:
'integration' and 'shell'. The 'integration' setup does not exclude the
integration-tests suite, and so can be used to run the integration tests.
The 'shell' setup does the same, but additionally sets $TEST_SHELL=1,
allowing to get rid of $TEST_SHELL in the docs.
vsc_tag() always reruns even if the vcs-tag option is disabled. Let's
use custom_target() instead so that we can only enable build_always_stale
if the vcs-tag option is enabled.
This new tool looks for a three xattr on the root inode of a file system
that encode mount constraints of the file system. The tool is supposed
to be hooke into the mount logic and is supposed to protect against
misappropriating trusted file systems in unintended ways.
Consider the following scenario: we boot up on first boot and create a
tpm-locked pair of /var/ and /srv/ partitions via systemd-repart. An
attacker then offline modifies the partition table, exchanging the
metadata of the /var/ and /srv/ partition. So far we'd happily accept
that, honour the modified metadata and boot up. This could be used to
revert changes to /var/ or similar. And all that even though both
partitions are encrypted and locked to TPM!
With this new mechanism we can encode in the protected contents of the
file systems the ways it can be used: the partition type uuid, the
partition label and the intended mount point can be stored in xattrs,
and we can check them automatically on mount, and take action on
mismatch. (action would typically be immediate reboot).
Currently, to run the integration tests, it's still necessary to
install various other build tools besides meson: A compiler, gperf,
libcap, ... which we want to avoid in CI systems where we receive
prebuilt systemd packages and only want to test them. Examples are
Debian's autopkgtest CI and Fedora CI. Let's make it possible for
these systems to run the integration tests without having to install
any other build dependency besides meson by extracting the logic
required to run the integration tests with meson into a separate
subdirectory and adding a standalone top-level meson.build file which
can be used to configure a meson tree with as its only purpose running
the integration tests.
Practically, we do the following:
- all the integration test directories and integration-test-wrapper.py
are moved from test/ to test/integration-tests/.
- All the installation logic is kept out of test/integration-tests/ or
any of its subdirectories and moved into test/meson.build instead.
- We add test/integration-tests/standalone/meson.build to run the
integration tests standalone. This meson file includes
test/integration-tests via a cute symlink hack to trick meson into
including a parent directory with subdir().
- Documentation is included on how to use the new standalone mode.
The semantics of strong inhibitors require that POLKIT_ALWAYS_QUERY
always be set when checking if we can allow blocking inhibitors to be
ignored on shutdown, reboot, etc. With the default polkit rules and
policy, users may experience a situation where users in the sudo group
are authorized to run:
systemctl reboot --check-inhibitors=no
but the root user is not authorized. Instead, the following error is
given:
Call to Reboot failed: Interactive authentication required.
While this is correct according to the semantics of strong inhibitors,
it is confusing. To help the situation, provide example polkit rules
that allow root to perform these actions.
Finally, when root receives SD_BUS_ERROR_INTERACTIVE_AUTHORIZATION_REQUIRED
when calling e.g. systemctl reboot, print a message explaining that this
is due to the current polkit policy, and point to the new example rule.
Related: https://github.com/systemd/systemd/issues/36786
Then we can detect the error fixed by the previous commit like the following:
../src/libsystemd/sd-device/test-sd-device.c: In function ‘test_sd_device_enumerator_add_all_parents’:
../src/shared/tests.h:225:51: error: comparison of constant ‘0’ with boolean expression is always true [-Werror=bool-compare]
225 | #define ASSERT_OK(expr) __coverity_check__((expr) >= 0)
| ^~
../src/libsystemd/sd-device/test-sd-device.c:547:9: note: in expansion of macro ‘ASSERT_OK’
547 | ASSERT_OK(sd_device_enumerator_add_all_parents(e) >= 0);
| ^~~~~~~~~
Now our baseline of meson is 0.62, hence install_symlink() can be used.
Note, install_symlink() implies install_emptydir() for specified
install_dir. Hence, this also drops several unnecessary
install_emptydir() calls.
Note, the function currently does not support 'relative' and 'force' flags,
so several 'ln -frsT' inline calls cannot be replaced.
The commit 8442ac9c02 set
install_tag option to install_emptydir() calls, but it requires
meson-0.62.0. Hence, after the commit, we cannot build systemd
with older meson anymore. As using install_tag is quite useful
for building systemd package, let's bump the requirement of
meson version to 0.62.0.
Note, the current meson versions of major distributions are:
CentOS 9: 0.63.3
CentOS 10: 1.4.1
Fedora 40: 1.4.1
Fedora 41: 1.5.1
Ubuntu 20.04 LTS (focal): 0.53.2 -- EOL on 2025-04
Ubuntu 22.04 LTS (jammy): 0.61.2 -- EOL on 2027-04
Ubuntu 24.04 LTS (noble): 1.3.2
Ubuntu 24.10 (oracular): 1.5.2
Debian 11 (bullseye): 0.56.2 (1.0.0 in backports) -- EOL on 2024-08
Debian 12 (bookworm): 1.0.1 (1.5.1 in backports)
openSUSE Leap 15.6: 1.6.1
openSUSE Tumbleweed: 1.6.1
As the next version (v258) is not expected to be released before
the end of 2025-04, it is OK to cut the support of Ubuntu 20.04 LTS and
Debian 11. Also, our policy for support of distributions explicitly says
only latest Ubuntu LTS and non-LTS releases are supported.
Hence, we can also cut Ubuntu 22.04, even if it is not EOL.
Follow-up for 8442ac9c02.
Closes#35967.
This introduces a bunch of facilities:
1. The factory-reset.target unit that requests a factory reset is now
complemented by factory-reset-now.target that executes it at next
boot.
2. This latter is added to the initial transaction via the new trivial
systemd-factory-reset-generator.
3. A tool systemd-factory-reset has been added to query, request,
cancel, complete factory reset operations (via EFI variables). Two of
these are wrapped into units that are plugged into
factory-reset.target and factory-reset-now.target respectively. The
tool also provides a simple Varlink API.
This should make things a lot cleaner, and both be useful as explicit
implementation on UEFI, and as template + hookpoints for alternative
implementations on non-UEFI.
glibc exports getdents64 syscall as is, but musl exports it as
posix_getdents(). Let's introduce a simple wrapper of posix_getdents().
Note, our baseline for glibc is 2.31. Hence, we can assume getdents64()
always defined when building with glibc.
To resolve conflict with sys/mount.h and linux/mount.h or linux/fs.h.
The conflict between sys/mount.h and linux/mount.h is resolved in
glibc-2.37 (774058d72942249f71d74e7f2b639f77184160a6), but our baseline
is still glibc-2.31. Also, even with the version or newer, still
sys/mount.h conflicts with linux/fs.h, which is included by
linux/btrfs.h.
This introduces our own implementation of sys/mount.h, that can be
simultaneously included with linux/mount.h and linux/fs.h. This also
imports linux/fs.h, linux/mount.h, and several other dependent headers.
The introduced sys/mount.h header itself may not be enough simple, but
by using the header, we can drop most of workarounds in other source files.
struct statx in glibc header was introduced in glibc-2.28
(fd70af45528d59a00eb3190ef6706cb299488fcd), but at that time,
sys/stat.h conflicts with linux/stat.h. Since glibc-2.30
(5dad6ffbb2b76215cfcd38c3001778536ada8e8a), sys/stat.h includes
linux/stat.h if exists.
Since now our baseline of glibc is 2.31. Hence, we can drop workarounds
for struct statx by importing linux/stat.h from newer kernel (v6.14-rc4).
In Arch Linux we currently have a half-baked apparmor support,
in particular we cannot link systemd to libapparmor for service
context integration, since that will pull apparmor into base system.
Hence, let's turn this into a dlopen dep.
Ref: https://gitlab.archlinux.org/archlinux/packaging/packages/systemd/-/issues/22
