See https://bugzilla.redhat.com/show_bug.cgi?id=1893417 for the back story:
the fallback hostname matters a lot in certain environments. Right now the only
way to configure the fallback hostname is by recompiling systemd, which is
obviously problematic in case when the fallback hostname shall differ between
different editions of the same distro that share a single compiled rpm.
By making this overridable through an envvar, we're providing an escape hatch
without making this a top-level api. Later on a way to set this through
os-release is added, but I think the approach with the variable is still
useful. It it very convenient for testing, or to override settings only in a
particular service, etc.
This updates the docs about using fdisk/gdisk to make partitions with the right
partition type UUID as defined in the discoverable partitions spec.
Improve wording/grammar/formatting, and reflect that gdisk supports this as
well nowadays; see https://www.rodsbooks.com/gdisk/revisions.html
The wiki was slightly stale, and almost all the information there
was already present in the man page. I moved the remaing part (discussion)
into the man page and adjusted all links to point to the man page instead.
daemon(7) has a some examples of packaging scriptlets… I don't think it fits
there very well. Most likely they should be moved to systemd.preset(5) or maybe
even removed, but I'm leaving that for later.
Very old versions of meson did not include the subdirectory name in the
target name, so we started adding various "top-level" custom targets in
subdirectories. This was nice because the main meson.build file wasn't
as cluttered. But then meson started including the subdir name in the
target name. So let's move the definition to the root so we can have all
targets named uniformly.
While it's perfectly possible today to completely rely on mkosi for
building and testing systemd, to get code completion and other IDE
niceties to work properly, it's still necessary to build systemd
locally.
Recently, mkosi gained the ability to allow external programs to
communicate with the build script. We can use this feature to run
the clangd language server in the mkosi build image via a custom
build script to provide IDE features in editors without requiring
developers to build systemd on the host or install any of systemd's
build dependencies locally.
This commit adds the necessary information on how to set this up
to HACKING.md.
This adds the support for veritytab.
The veritytab file contains at most five fields, the first four are
mandatory, the last one is optional:
- The first field contains the name of the resulting verity volume; its
block device is set up /dev/mapper/</filename>.
- The second field contains a path to the underlying block data device,
or a specification of a block device via UUID= followed by the UUID.
- The third field contains a path to the underlying block hash device,
or a specification of a block device via UUID= followed by the UUID.
- The fourth field is the roothash in hexadecimal.
- The fifth field, if present, is a comma-delimited list of options.
The following options are recognized only: ignore-corruption,
restart-on-corruption, panic-on-corruption, ignore-zero-blocks,
check-at-most-once and root-hash-signature. The others options will
be implemented later.
Also, this adds support for the new kernel verity command line boolean
option "veritytab" which enables the read for veritytab, and the new
environment variable SYSTEMD_VERITYTAB which sets the path to the file
veritytab to read.
Sometimes, non-ramfs initrd root are useful. Eg, for kdump, because
initramfs is memory consuming, so mount a compressed image in earlier
initrd, chroot into it then let systemd do the rest of job is a good
solution.
But systemd doesn't recognize the initrd environment if rootfs is not a
temporary fs. This is a reasonable check, because switch-root in initrd
will wipe the whole rootfs, will be a disaster if there are any
misdetect.
So extend SYSTEMD_IN_INITRD environment variable, now it accepts boolean
value and two extra keyword, "auto" and "lenient". "auto" is same as
before, and it's the default value. "lenient" will let systemd bypass
the rootfs check.
The boot loader specification link points to the boot loader interface
documentation.
This fixes the link to point to BOOT_LOADER_SPECIFICATION instead of
BOOTLOADER_INTERFACE which is itself.
This only changes documentation. In various places we call "ninja"
directly. I figured it would be safer to leave those in place for now,
given the meson replacement commands lines appears to be supported in
newer meson versions only.
FixedRandomDelay=yes will use
`siphash24(sd_id128_get_machine() || MANAGER_IS_SYSTEM(m) || getuid() || u->id)`,
where || is concatenation, instead of a random number to choose a value between
0 and RandomizedDelaySec= as the timer delay.
This essentially sets up a fixed, but seemingly random, offset for each timer
iteration rather than having a random offset recalculated each time it fires.
Closes#10355
Co-author: Anita Zhang <the.anitazha@gmail.com>
Primarily:
1. Mention that we prefer if return parameters carry "ret_" as prefix in
their name
2. Clarify that debug-level logging is always OK, and irrelevant to when
deciding whether a function is logging or non-logging.
