It's a bit weird to test these strings after the fact instead of before.
Let's make sure that we don't even attempt the string escaping if the
strings are NULL.
Follow-up for #7688
This adds a simple condition/assert/match to the service manager, to
udev's .link handling and to networkd, for matching the kernel version
string.
In this version we only do fnmatch() based globbing, but we might want
to extend that to version comparisons later on, if we like, by slightly
extending the syntax with ">=", "<=", ">", "<" and "==" expressions.
Follow-up to @poettering’s comments in #7723:
- Slightly expand on the difference between using tmpfiles.d and service
directives
- Mention CacheDirectory=
- Mention LogsDirectory=
- Abbreviate and unify some later descriptions
ConfigDirectory= is not mentioned, since it does not support the
functionality mentioned in the manpage which tmpfiles.d provides:
copying or symlinking default configuration from /usr/share/factory. And
the user package variable file locations don’t mention the directives
because in user units the service can always create the directories
itself (whereas in system units lesser-privileged services lack
permission to create them).
Let's unify the code for parsing command line verbs, and reuse the
common verbs.[ch] API in systemd-analyze too.
This adds a couple of error messages when people pass too many
arguments. Moreover thus pushes bus allocation into the verb functions,
which corrects a couple of cases where we previously allocated a bus but
really didn't need to.
Other than that behaviour shouldn't really change.
The boot loader systemd-boot removes ".conf" from file name of entry
configs, and determine which entry is the default entry.
However, bootspec, which is used by systemctl and bootctl did not
remove ".conf", then sometimes bootctl marks wrong entry as default.
This fixes the logic to choose the default entry in bootspec, to
match the logic used in systemd-boot boot loader.
Fixes#7727.
We of course don't know in which header glibc will export pivot_root()
and if it ever will. But there's a good chance they'll place it where
chroot() is located, given the similarity in the operations, hence let's
try our luck and look for it at the same place.
If we are lucky this means we don't have to patch our code if glibc
decides to expose the call one day.
This reworks how we set _GNU_SOURCE when checking for the availability
of functions:
1. We set it for most of the functions we look for. After all we set it
for our entire built anyway, and it's usually how Linux-specific
definitions in glibc are protected these days. Given that we usually
have checks for such modern stuff only anyway, let's just blanket enable
it.
2. Use "args" instead of "prefix" to set the macro. This is what is
suggested in the meson docs, hence let's do it.
We make assumptions about the comm name we set via PR_SET_NAME: that it
would reflect the process name, but that's only the case for the main
thread. Moreover, we cache the mmap() region without locking.
Let's hence be safe rather than sorry and support all this only in the
main thread.
It's a relatively small wrapper around safe_fork() now, hence let's move
it over, and make its signature even more alike. Also, set a different
process name for the polkit and askpw agents.
This adds a new safe_fork() wrapper around fork() and makes use of it
everywhere. The new wrapper does a couple of things we previously did
manually and separately in a safer, more correct and automatic way:
1. Optionally resets signal handlers/mask in the child
2. Sets a name on all processes we fork off right after forking off (and
the patch assigns useful names for all processes we fork off now,
following a systematic naming scheme: always enclosed in () – in order
to indicate that these are not proper, exec()ed processes, but only
forked off children, and if the process is long-running with only our
own code, without execve()'ing something else, it gets am "sd-" prefix.)
3. Optionally closes all file descriptors in the child
4. Optionally sets a PR_SET_DEATHSIG to SIGTERM in the child, in a safe
way so that the parent dying before this happens being handled
safely.
5. Optionally reopens the logs
6. Optionally connects stdin/stdout/stderr to /dev/null
7. Debug logs about the forked off processes.
Ultimately, O_CLOEXEC should be off in fd 0, 1, 2, but when we open
/dev/null here it's unlikely to be < 0, and after dupping the fd to 0,
1, 2 we turn off O_CLOEXEC explicitly anyway.
Unless we know that what we are about to open will return 0, 1 or 2 we
should always set O_CLOEXEC in order to be safe to other threads forking
of subprocesses at the wrong moment.
Just a minor tweak, making sure we execute as much as we can of the
funciton, but return the first error instead of the last we encounter.
This is usuelly how we do things when we have functions that continue on
the first error, so let's do it like that here too.
Let's fork off sync() ina process instead of a thread, as a safety
measure. This is beneficial to ensure that the original process can exit
without having to wait for the sync() to finish (note that the kernel
will delay process termination until all threads finished their
syscalls). In case of hanging NFS this increases the chance that PID 1
can safely transition to the "systemd-shutdown" process as the sync() is
initiated early on but definitely not waited for.
Follow-up for bad7a0c81f501fbbcc79af9eaa4b8254441c4a1f of git
repository for glibc.
Recently glibc added `copy_file_range()`, but to use it,
`_GNU_SOURCE` needs to be defined. This adds the flag in
meson.build to detect the function by meson correctly.
