And let's make use of it to implement two new unit settings with it:
1. LogLevelMax= is a new per-unit setting that may be used to configure
log priority filtering: set it to LogLevelMax=notice and only
messages of level "notice" and lower (i.e. more important) will be
processed, all others are dropped.
2. LogExtraFields= is a new per-unit setting for configuring per-unit
journal fields, that are implicitly included in every log record
generated by the unit's processes. It takes field/value pairs in the
form of FOO=BAR.
Also, related to this, one exisiting unit setting is ported to this new
facility:
3. The invocation ID is now pulled from /run/systemd/units/ instead of
cgroupfs xattrs. This substantially relaxes requirements of systemd
on the kernel version and the privileges it runs with (specifically,
cgroupfs xattrs are not available in containers, since they are
stored in kernel memory, and hence are unsafe to permit to lesser
privileged code).
/run/systemd/units/ is a new directory, which contains a number of files
and symlinks encoding the above information. PID 1 creates and manages
these files, and journald reads them from there.
Note that this is supposed to be a direct path between PID 1 and the
journal only, due to the special runtime environment the journal runs
in. Normally, today we shouldn't introduce new interfaces that (mis-)use
a file system as IPC framework, and instead just an IPC system, but this
is very hard to do between the journal and PID 1, as long as the IPC
system is a subject PID 1 manages, and itself a client to the journal.
This patch cleans up a couple of types used in journal code:
specifically we switch to size_t for a couple of memory-sizing values,
as size_t is the right choice for everything that is memory.
Fixes: #4089Fixes: #3041Fixes: #4441
Fix loginctl seat sysfs tree ellipsation logic.
Simple reproducer:
loginctl --full seat-status seat0|cat
→ after this PR, all lines are shown in full. Before, lines were ellipsized to terminal width.
Let's say that (size_t) -1 (i.e. SIZE_T_MAX) is equivalent to
"unbounded" ellipsation, i.e. ellipsation as NOP. In which case the
relevant functions become little more than strdup()/strndup().
This is useful to simplify caller code in case we want to turn off
ellipsation in certain code paths with minimal caller-side handling for
this.
It was dropped in 89439d4fc0. As a result, every
process that uses a hashmap allocates and then leaks the hashmap mempools.
The mempools are only allocated in the main thread, but we don't know where
the memory is used.
So let's check if we are the last thread and free the mempools then. This is
fairly heavy, because /proc/self/status has to be opened and parsed, but we do
it only when compiled for valgrind, i.e. not by default, and compared to running
under valgrind or asan, the extra cost is acceptable. The big advantage is that
we don't have to think or filter out this false positive.
As a micro-opt, cleanup is attempted only in the main thread. We could allow
any thread to check if it is the last one and perform cleanup, but that'd mean
that we'd have to _do_ the check in every thread. We don't use threads like
that, our non-main threads are always short-lived, so let's just accept the
possibility that we'll leak memory if a thread survives. The check is also
non-atomic, but it's called in a destructor of the main thread _and_ we do
cleanup only when there are no other threads, so the risk of some library
suddenly spawning another thread is very low. All in all, this is not perfect,
but should work in 999‰ of cases.
Fixes the following valgrind warning:
==22564== HEAP SUMMARY:
==22564== in use at exit: 8,192 bytes in 2 blocks
==22564== total heap usage: 243 allocs, 241 frees, 151,905 bytes allocated
==22564==
==22564== 4,096 bytes in 1 blocks are still reachable in loss record 1 of 2
==22564== at 0x4C2FB6B: malloc (vg_replace_malloc.c:299)
==22564== by 0x4F08A8C: mempool_alloc_tile (mempool.c:62)
==22564== by 0x4F08B16: mempool_alloc0_tile (mempool.c:81)
==22564== by 0x4EF8DE0: hashmap_base_new (hashmap.c:748)
==22564== by 0x4EF8ED9: internal_hashmap_new (hashmap.c:782)
==22564== by 0x11045D: test_hashmap_copy (test-hashmap-plain.c:87)
==22564== by 0x115722: test_hashmap_funcs (test-hashmap-plain.c:914)
==22564== by 0x10FC9D: main (test-hashmap.c:60)
==22564==
==22564== 4,096 bytes in 1 blocks are still reachable in loss record 2 of 2
==22564== at 0x4C2FB6B: malloc (vg_replace_malloc.c:299)
==22564== by 0x4F08A8C: mempool_alloc_tile (mempool.c:62)
==22564== by 0x4F08B16: mempool_alloc0_tile (mempool.c:81)
==22564== by 0x4EF8DE0: hashmap_base_new (hashmap.c:748)
==22564== by 0x4EF8EF8: internal_ordered_hashmap_new (hashmap.c:786)
==22564== by 0x10A2A0: test_ordered_hashmap_copy (test-hashmap-ordered.c:89)
==22564== by 0x10F70F: test_ordered_hashmap_funcs (test-hashmap-ordered.c:916)
==22564== by 0x10FCA2: main (test-hashmap.c:61)
==22564==
==22564== LEAK SUMMARY:
==22564== definitely lost: 0 bytes in 0 blocks
==22564== indirectly lost: 0 bytes in 0 blocks
==22564== possibly lost: 0 bytes in 0 blocks
==22564== still reachable: 8,192 bytes in 2 blocks
==22564== suppressed: 0 bytes in 0 blocks
v2:
- check if we are the main thread
v3:
- check if there are no other threads
_unused_ means "the variable is meant to be possible unused and gcc
will not generate a warning about it", which is exactly what we need here,
since we're only declaring it for the side effect of _cleanup_.
If we follow an absolute symlink there's no need to prefix the path with
a "/", since by definition it already has one.
This helps suppressing double "/" in resolved paths containing absolute
symlinks.
Some of the btrfs utility functions already used O_NOFOLLOW others
didn't. Let's streamline this, and refuse operation when we are called
for symlinks on "remove" and "snapshot" too.
In particular in the "remove" case following symlinks is a bad idea, and
is quite different from how unlink() and friends work, which always
remove the symlink, and not the destination, a logic we should follow
here too.
When using strftime in arbitrary locales, we cannot really say how big the
buffer should be. Let's make the buffer "large", which will work fine pretty
much always, and just print n/a if the timestamp does not fit. strftime returns
0 if the buffer is too small and a NUL-terminated string otherwise, so we
can drop the size specifications in string formatting.
$ export LANG=fa_IR.UTF-8
$ date
چهارشنبه ۱۸ اكتبر ۱۷، ساعت ۱۰:۵۴:۲۴ (+0330)
$ timedatectl
Assertion 'xstrftime: a[] must be big enough' failed at ../src/timedate/timedatectl.c:105, function print_status_info(). Aborting.
now:
$ timedatectl
Local time: چهارشنبه 2017-10-18 16:29:40 CEST
Universal time: چهارشنبه 2017-10-18 14:29:40 UTC
RTC time: چهارشنبه 2017-10-18 14:29:40
…
https://bugzilla.redhat.com/show_bug.cgi?id=1503452
It always bothered me a bit that unit-name.[ch] contains so many
definitions that aren't really have much to do with unit nameing, for
example all the unit state definitions.
With this patch unit-name.[ch] is split into two: the file now contains
only the unit naming related operations, and everything else is split
out into a new set of files unit-def.[ch]. That's mostly unit state
stuff as well as dbus path and interface name operations.
No functional changes. This just moves code around.
(Note as both .c files include each other's headers this doesn't make
the build simpler or anything. All it does is make the C files a bit
shorter, and medicate my pretend OCD)
The environment variables we've serialized can quite possibly contain
characters outside the set allowed by env_assignment_is_valid(). In
fact, my environment seems to contain a couple of these:
* TERMCAP set by screen contains a '\x7f' character
* BASH_FUNC_module%% variable has a '%' character in name
Strict check of environment variables name and value certainly makes sense for
unit files, but not so much for deserialization of values we already had
in our environment.
We added JobRunningTimeoutSec= late, and Dracut configured only
JobTimeoutSec= to turn of root device timeouts before. With this change
we'll propagate a reset of JobTimeoutSec= into JobRunningTimeoutSec=,
but only if the latter wasn't set explicitly.
This should restore compatibility with older systemd versions.
Fixes: #6402
STR_IN_SET is a newer approach which is easier to write and read, and which
seems to result in space savings too:
before:
4949848 build/src/shared/libsystemd-shared-234.so
350704 build/systemctl
4967184 build/systemd
826216 build/udevadm
after:
4949848 build/src/shared/libsystemd-shared-234.so
350704 build/systemctl
4966888 build/systemd
826168 build/udevadm
The advantage is that is the name is mispellt, cpp will warn us.
$ git grep -Ee "conf.set\('(HAVE|ENABLE)_" -l|xargs sed -r -i "s/conf.set\('(HAVE|ENABLE)_/conf.set10('\1_/"
$ git grep -Ee '#ifn?def (HAVE|ENABLE)' -l|xargs sed -r -i 's/#ifdef (HAVE|ENABLE)/#if \1/; s/#ifndef (HAVE|ENABLE)/#if ! \1/;'
$ git grep -Ee 'if.*defined\(HAVE' -l|xargs sed -i -r 's/defined\((HAVE_[A-Z0-9_]*)\)/\1/g'
$ git grep -Ee 'if.*defined\(ENABLE' -l|xargs sed -i -r 's/defined\((ENABLE_[A-Z0-9_]*)\)/\1/g'
+ manual changes to meson.build
squash! build-sys: use #if Y instead of #ifdef Y everywhere
v2:
- fix incorrect setting of HAVE_LIBIDN2
This reverts commit ee043777be.
It broke almost everywhere it touched. The places that
handn't been converted, were mostly followed by special
handling for the invalid PID `0`. That explains why they
tested for `pid < 0` instead of `pid <= 0`.
I think that one was the first commit I reviewed, heh.
This is a legacy of autotools, where one detection routine used a different
prefix then the others.
$ git grep -e HAVE_DECL_ -l|xargs sed -i s/HAVE_DECL_/HAVE_/g
Don't miscount number of "../" to generate, if we "." is included in an
input path.
Also, refuse if we encounter "../" since we can't possibly follow that
up properly, without file system access.
Some other modernizations.
