We typically want to deal in usec_t, hence let's change the prototype
accordingly, and do proper range checks. Also, make sure are not
confused by negative times.
Do something similar for mktime_or_timegm().
This is a more comprehensive alternative to #34065
Replaces: #34065
Anything that is part of src/shared becomes part of the shared library, which
is wasteful, because the library is linked into almost all binaries. The
library is also forms a separate link unit, so this prevents the function from
being inlined or such.
Also, move logging into the function. Now that it's not a library function,
there is no reason not to do that.
No functional change yet, just moving stuff around and message format
adjustments.
EPOCH_CLOCK_FILE is also made public for consistency, even though I don't
plan to use it outside of the one location.
-1 was used everywhere, but -EBADF or -EBADFD started being used in various
places. Let's make things consistent in the new style.
Note that there are two candidates:
EBADF 9 Bad file descriptor
EBADFD 77 File descriptor in bad state
Since we're initializating the fd, we're just assigning a value that means
"no fd yet", so it's just a bad file descriptor, and the first errno fits
better. If instead we had a valid file descriptor that became invalid because
of some operation or state change, the other errno would fit better.
In some places, initialization is dropped if unnecessary.
There might be (embedded) systems that get never updated (things like
e.g. entertainment systems of trains, for example) and where the adjustment of
the system clock (introduced by b10abe4bba) would
do the wrong thing even if the difference between the systemd build time and
the rtc is 15 years or more.
This patch allows disabling the adjustment by setting
'clock-valid-range-usec-max' meson option to 0 or to a negative value.
With some versions of the compiler, the _cleanup_ attr makes it think
the variable might be freed/closed when uninitialized, even though it
cannot happen. The added cost is small enough to be worth the benefit,
and optimized builds will help reduce it even further.
On systems without an RTC, systemd currently sets the clock to a
compile-time epoch value, derived from the NEWS file in the
repository. This is not ideal as the initial clock hence depends
on the last time systemd was built, not when the image was compiled.
Let's provide a different way here and look at `/usr/lib/clock-epoch`.
If that file exists, it's timestamp for the last modification will be
used instead of the compile-time default.
This doesn't have much effect on the final build, because we link libbasic.a
into libsystemd-shared.so, so in the end, all the object built from basic/
end up in libsystemd-shared. And when the static library is linked into binaries,
any objects that are included in it but are not used are trimmed. Hence, the
size of output artifacts doesn't change:
$ du -sb /var/tmp/inst*
54181861 /var/tmp/inst1 (old)
54207441 /var/tmp/inst1s (old split-usr)
54182477 /var/tmp/inst2 (new)
54208041 /var/tmp/inst2s (new split-usr)
(The negligible change in size is because libsystemd-shared.so is bigger
by a few hundred bytes. I guess it's because symbols are named differently
or something like that.)
The effect is on the build process, in particular partial builds. This change
effectively moves the requirements on some build steps toward the leaves of the
dependency tree. Two effects:
- when building items that do not depend on libsystemd-shared, we
build less stuff for libbasic.a (which wouldn't be used anyway,
so it's a net win).
- when building items that do depend on libshared, we reduce libbasic.a as a
synchronization point, possibly allowing better parallelism.
Method:
1. copy list of .h files from src/basic/meson.build to /tmp/basic
2. $ for i in $(grep '.h$' /tmp/basic); do echo $i; git --no-pager grep "include \"$i\"" src/basic/ 'src/lib*' 'src/nss-*' 'src/journal/sd-journal.c' |grep -v "${i%.h}.c";echo ;done | less
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.
We can not reliably manage any notion of local time. Every daylight
saving time change or time zone change by traveling will make the
time jump, and the local time might jump backwards which creates
unsolvable problems with file timestamps.
We will no longer tell the kernel our local time zone and leave
everything set to UTC. This will effectively turn FAT timestamps
into UTC timestamps.
If and only if the machine is configured to read the RTC in local
time mode, the kernel's time zone will be configured, but
systemd-timesysnc will disable the kernel's system time to RTC
syncing. In this mode, the RTC will not be managed, and external
tools like Windows bootups are expected to manage the RTC's time.
https://bugs.freedesktop.org/show_bug.cgi?id=81538
Create initial stamp file with compiled-in time to prevent bootups
with clocks in the future from storing invalid timestamps.
At shutdown, only update the timestamp if we got an authoritative
time to store.
Daan De Meyer
Lennart Poettering
Zbigniew Jędrzejewski-Szmek
Franck Bui
Egor Ignatov
Luca Boccassi
Yu Watanabe
Daniel Mack
Kay Sievers
Thomas Hindoe Paaboel Andersen
Torstein Husebø