This way we can quickly find the most recent entry, without searching or
traversing entry array chains.
This is relevant later, as it it allows us to quickly determine the most
recent timestamps of each journal file, in a roughly atomic way.
(The one case that is left unchanged is '< <(subcommand)'.)
This way, the style with no gap was already dominant. This way, the reader
immediately knows that ' < ' is a comparison operator and ' << ' is a shift.
In a few cases, replace custom EOF replacement by just EOF. There is no point
in using someting like "_EOL" unless "EOF" appears in the text.
The documentation on moving an existing homedir into a systemd-homed managed
one suggests using rsync(1) with a bunch of flags to preserve as much metadata
as possible: permissions, xattrs, timestamps, etc. The previously suggested
flags were:
rsync -aHAXv --remove-source-files …
… which does include mtimes, but not ctimes and atimes, because -a does not
include those:
--archive, -a archive mode is -rlptgoD (no -A,-X,-U,-N,-H)
This change adds the -N and -U flags to preserve even more file timestamps,
turning the command into:
rsync -aHANUXv --remove-source-files …
The new flags are:
--crtimes, -N preserve create times (newness)
--atimes, -U preserve access (use) times
Let's introduce a common implementation of a function that checks
whether we are booted on a kernel with systemd-stub that has TPM PCR
measurements enabled. Do our own userspace measurements only if we
detect that.
PCRs are scarce and most likely there are projects which already make
use of them in other ways. Hence, instead of blindly stepping into their
territory let's conditionalize things so that people have to explicitly
buy into our PCR assignments before we start measuring things into them.
Specifically bind everything to an UKI that reported measurements.
This was previously already implemented in systemd-pcrphase, but with
this change we expand this to all tools that process PCR measurement
settings.
The env var to override the check is renamed to SYSTEMD_FORCE_MEASURE,
to make it more generic (since we'll use it at multiple places now).
This is not a compat break, since the original env var for that was not
included in any stable release yet.
This was dropped on reviewers' request in the revision that got merged,
but reference in two documents was not updated. Fix it.
Follow-up for: https://github.com/systemd/systemd/pull/25918
