With the switch from log_debug() to log_debug_errno() in commit c413bb28df
systemd-update-done would fail without any error message if /etc
or /var were read-only. This restores the previous behaviour to
silently ignore these directories again.
In various cases, we would say 'return log_warning()' or 'return log_error()'. Those
functions return 0 if no error is passed in. For log_warning or log_error this doesn't
make sense, and we generally want to propagate the error. In the few cases where
the error should be ignored, I think it's better to split it in two, and call 'return 0'
on a separate line.
These lines are generally out-of-date, incomplete and unnecessary. With
SPDX and git repository much more accurate and fine grained information
about licensing and authorship is available, hence let's drop the
per-file copyright notice. Of course, removing copyright lines of others
is problematic, hence this commit only removes my own lines and leaves
all others untouched. It might be nicer if sooner or later those could
go away too, making git the only and accurate source of authorship
information.
This part of the copyright blurb stems from the GPL use recommendations:
https://www.gnu.org/licenses/gpl-howto.en.html
The concept appears to originate in times where version control was per
file, instead of per tree, and was a way to glue the files together.
Ultimately, we nowadays don't live in that world anymore, and this
information is entirely useless anyway, as people are very welcome to
copy these files into any projects they like, and they shouldn't have to
change bits that are part of our copyright header for that.
hence, let's just get rid of this old cruft, and shorten our codebase a
bit.
Files which are installed as-is (any .service and other unit files, .conf
files, .policy files, etc), are left as is. My assumption is that SPDX
identifiers are not yet that well known, so it's better to retain the
extended header to avoid any doubt.
I also kept any copyright lines. We can probably remove them, but it'd nice to
obtain explicit acks from all involved authors before doing that.
'/etc/.updated' is created without using a temporary file, this can be
problematic with filesystems that cache writes. Modify so that the
timestamp is written to a temporary file and then use an atomic move
to move it to its correct place.
This is a follow-up for fb8b0869a7, and makes a
couple of minor clean-up changes:
- The field name in the timestamp file is changed from "TimestampNSec=" to
"TIMESTAMP_NSEC=". This is done simply to reflect the fact that we parse the
file with the env var file parser, and hence the contents should better
follow the usual capitalization of env vars, i.e. be all uppercase.
- Needless negation of the errno parameter log_error_errno() and friends has
been removed.
- Instead of manually calculating the nsec remainder of the timestamp, use
timespec_store().
- We now check whether we were able to write the timestamp file in full with
fflush_and_check() the way we usually do it.
This patch removes includes that are not used. The removals were found with
include-what-you-use which checks if any of the symbols from a header is
in use.
As a followup to 086891e5c1 "log: add an "error" parameter to all
low-level logging calls and intrdouce log_error_errno() as log calls
that take error numbers", use sed to convert the simple cases to use
the new macros:
find . -name '*.[ch]' | xargs sed -r -i -e \
's/log_(debug|info|notice|warning|error|emergency)\("(.*)%s"(.*), strerror\(-([a-zA-Z_]+)\)\);/log_\1_errno(-\4, "\2%m"\3);/'
Multi-line log_*() invocations are not covered.
And we also should add log_unit_*_errno().
In order to support offline updates to /usr, we need to be able to run
certain tasks on next boot-up to bring /etc and /var in line with the
updated /usr. Hence, let's devise a mechanism how we can detect whether
/etc or /var are not up-to-date with /usr anymore: we keep "touch
files" in /etc/.updated and /var/.updated that are mtime-compared with
/usr. This means:
Whenever the vendor OS tree in /usr is updated, and any services that
shall be executed at next boot shall be triggered, it is sufficient to
update the mtime of /usr itself. At next boot, if /etc/.updated and/or
/var/.updated is older than than /usr (or missing), we know we have to
run the update tools once. After that is completed we need to update the
mtime of these files to the one of /usr, to keep track that we made the
necessary updates, and won't repeat them on next reboot.
A subsequent commit adds a new ConditionNeedsUpdate= condition that
allows checking on boot whether /etc or /var are outdated and need
updating.
This is an early step to allow booting up with an empty /etc, with
automatic rebuilding of the necessary cache files or user databases
therein, as well as supporting later updates of /usr that then propagate
to /etc and /var again.
Yu Watanabe