Introduce rootpkglibdir for installing libsystemd-{shared,core}.so.
The benefit over using rootlibexecdir is that this path can be
multiarch aware, i.e. this path can be architecture qualified.
This is something we'd like to make use of in Debian/Ubuntu to make
libsystemd-shared co-installable, e.g. for i386 the path would be
/usr/lib/i386-linux-gnu/systemd/libsystemd-shared-*.so and for amd64
/usr/lib/x86_64-linux-gnu/systemd/libsystemd-shared-*.so.
This will allow for example to install and run systemd-boot/i386 on an
amd64 host. It also simplifies/enables cross-building/bootstrapping.
For more infos about Multi-Arch see https://wiki.debian.org/Multiarch.
See also https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=990547
We would use a relative path, looking for globs like
'lib/systemd/libsystemd-shared-*.so' under the build directory, and never find
anything.
The test was supposed to find library in the current installation. But we
cannot assume that the right library is installed, so the test only printed the
result for manual inspection. Thus nobody noticed when it broke. I think it
broke in c6134d3e2f, path-util: get rid of prefix_root().
But that commit doesn't compile because of changes in meson, so this is just
a guess.
Before:
/* test_systemd_installation_has_version */
Current installation has systemd >= 0: no
Current installation has systemd >= 231: no
Current installation has systemd >= 249: no
Current installation has systemd >= 999: no
With the fix:
$ build/test-nspawn-util
/* test_systemd_installation_has_version */
Found libsystemd shared at "/lib/systemd/libsystemd-shared-245.so.so", version 245 (OK).
Current installation has systemd >= 0: yes
Found libsystemd shared at "/lib/systemd/libsystemd-shared-245.so.so", version 245 (OK).
Current installation has systemd >= 231: yes
Found libsystemd shared at "/lib/systemd/libsystemd-shared-245.so.so", version 245 (too old).
Found libsystemd shared at "/lib/systemd/libsystemd-shared-251.so.so", version 251 (OK).
Current installation has systemd >= 251: yes
Found libsystemd shared at "/lib/systemd/libsystemd-shared-245.so.so", version 245 (too old).
Found libsystemd shared at "/lib/systemd/libsystemd-shared-251.so.so", version 251 (too old).
Found libsystemd shared at "/lib/systemd/libsystemd-shared-250.so.so", version 250 (too old).
Found libsystemd shared at "/usr/lib/systemd/libsystemd-shared-245.so.so", version 245 (too old).
Found libsystemd shared at "/usr/lib/systemd/libsystemd-shared-251.so.so", version 251 (too old).
Found libsystemd shared at "/usr/lib/systemd/libsystemd-shared-250.so.so", version 250 (too old).
Current installation has systemd >= 999: no
$ build/test-nspawn-util /var/lib/machines/rawhide
/* test_systemd_installation_has_version */
/* test_systemd_installation_has_version */
Found libsystemd shared at "/var/lib/machines/rawhide/lib/systemd/libsystemd-shared-251-rc1-1.fc37.so.so", version 251 (OK).
/var/lib/machines/rawhide has systemd >= 0: yes
Found libsystemd shared at "/var/lib/machines/rawhide/lib/systemd/libsystemd-shared-251-rc1-1.fc37.so.so", version 251 (OK).
/var/lib/machines/rawhide has systemd >= 231: yes
Found libsystemd shared at "/var/lib/machines/rawhide/lib/systemd/libsystemd-shared-251-rc1-1.fc37.so.so", version 251 (OK).
/var/lib/machines/rawhide has systemd >= 251: yes
Found libsystemd shared at "/var/lib/machines/rawhide/lib/systemd/libsystemd-shared-251-rc1-1.fc37.so.so", version 251 (too old).
Found libsystemd shared at "/var/lib/machines/rawhide/usr/lib/systemd/libsystemd-shared-251-rc1-1.fc37.so.so", version 251 (too old).
/var/lib/machines/rawhide has systemd >= 999: no
While at it, NULSTR_FOREACH → FOREACH_STRING.
See a2b0cd3f5a. When -Dshared-lib-tag is used,
libsystemd-shared.so and libsystemd-core.so get a suffix which breaks the
parsing done by systemd_installation_has_version(). We can assume that the
tag will be something like "251-rc1-1.fc37" that is currently used in Fedora.
(Anything that does *not* start with the version would be completely crazy.)
By switching to strverscmp_improved() we simplify the code and fix comparisons
with such versions.
$ build/test-nspawn-util /var/lib/machines/rawhide
...
Found libsystemd shared at "/var/lib/machines/rawhide/lib/systemd/libsystemd-shared-251-rc1-1.fc37.so.so", version 251-rc1-1.fc37 (OK).
/var/lib/machines/rawhide has systemd >= 251: yes
...
I noticed this when I started a systemd-nspawn container with Redora rawhide
and got the message "Not running with unified cgroup hierarchy, LSM BPF is not
supported". I thought the message is in error, but it was actually correct:
nspawn was misdetecting that the container does not sport new-enough systemd
to support cgroups-v2.
This function implements a heuristic that is only used by nspawn. It doesn't
belong in basic. I opted for a new file "nspawn-utils.c", because it seems
likely that we'll need some other new utilities like that in the future.
No functional change.
Michael Biebl
Zbigniew Jędrzejewski-Szmek