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.
Double newlines (i.e. one empty lines) are great to structure code. But
let's avoid triple newlines (i.e. two empty lines), quadruple newlines,
quintuple newlines, …, that's just spurious whitespace.
It's an easy way to drop 121 lines of code, and keeps the coding style
of our sources a bit tigther.
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.
By default systemd-shutdown will wait for 90s after SIGTERM was sent
for all processes to exit. This is way too long and effectively defeats
an emergency watchdog reboot via "reboot-force" actions. Instead now
use DefaultTimeoutStopSec which is configurable.
Using `kill()` with a signal of 0 is a slightly more documented idiom for
checking whether a process still exists. It is mentioned explicitly in
man pages. This avoids the need to comment the call as "misuse".
A comment is still necessary - in fact this idiom is even more confusing if
you don't know how it works. But it's easy enough to explain.
We don't have plural in the name of any other -util files and this
inconsistency trips me up every time I try to type this file name
from memory. "formats-util" is even hard to pronounce.
There's really no reason to use 10s here, let's instead default to 90s like we
do for everything else.
The SIGKILL during the final killing spree is in most regards the fourth level
of a safety net, after all: any normal service should have already been stopped
during the normal service shutdown logic, first via SIGTERM and then SIGKILL,
and then also via SIGTERM during the finall killing spree before we send
SIGKILL. And as a fourth level safety net it should only be required in
exceptional cases, which means it's safe to rais the default timeout, as normal
shutdowns should never be delayed by it.
Note that journald excludes itself from the normal service shutdown, and relies
on the final killing spree to terminate it (this is because it wants to cover
the normal shutdown phase's complete logging). If the system's IO is
excessively slow, then the 10s might not be enough for journald to sync
everything to disk and logs might get lost during shutdown.
There are more than enough calls doing string manipulations to deserve
its own files, hence do something about it.
This patch also sorts the #include blocks of all files that needed to be
updated, according to the sorting suggestions from CODING_STYLE. Since
pretty much every file needs our string manipulation functions this
effectively means that most files have sorted #include blocks now.
Also touches a few unrelated include files.
This adds a new PID_TO_PTR() macro, plus PTR_TO_PID() and makes use of
it wherever we maintain processes in a hash table. Previously we
sometimes used LONG_TO_PTR() and other times ULONG_TO_PTR() for that,
hence let's make this more explicit and clean up things.
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.
If the format string contains %m, clearly errno must have a meaningful
value, so we might as well use log_*_errno to have ERRNO= logged.
Using:
find . -name '*.[ch]' | xargs sed -r -i -e \
's/log_(debug|info|notice|warning|error|emergency)\((".*%m.*")/log_\1_errno(errno, \2/'
Plus some whitespace, linewrap, and indent adjustments.
It is redundant to store 'hash' and 'compare' function pointers in
struct Hashmap separately. The functions always comprise a pair.
Store a single pointer to struct hash_ops instead.
systemd keeps hundreds of hashmaps, so this saves a little bit of
memory.
static int killall(....) in ./src/core/killall.c tries to get "s"
initialized by calling get_process_comm(...) which calls
read_one_line_file(...) which if it fails will mean it is left
uninitialized.
It is then used in argument to strna(s) call where it is
dereferenced(!), in addition to nothing else initializing it before
the scope it is in finishes.
It is nicer to predefine patterns using configure time check instead of
using casts everywhere.
Since we do not need to use any flags, include "%" in the format instead
of excluding it like PRI* macros.
Previously we simply counted how many processes we killed and expected
as many waitpid() calls to succeed. That however is incorrect to do.
As we might kill processes that are not our immediate children, and as
there might be left-over processes in the waitpid() queue from earlier
the we might get more ore less waitpid() events that we expect.
Hence: keep precise track of the processes we kill, remove the ones we
get waitpid() for, and after each time we get SIGCHLD check if all
others still exist. We use getpgid() to check if a PID still exists.
This should fix issues with journald not setting journal files offline
correctly on shutdown, because we'd too quickly proceed from SIGTERM to
SIGKILL because some left-over process was in our waitpid() queue.