Just in case something opened them, let's make sure glibc invalidates
them too.
Thankfully so far no library opened log channels behind our back, at
least as far as I know, hence this is actually a NOP, but let's better
be safe than sorry.
Now that logging can implicitly reopen the log streams when needed we
can log errors without any special magic, hence let's normalize things,
and log the same way we do everywhere else.
This we can then make use in execute.c to make error logging a bit less
special when preparing for process execution, as we can still log but
don't have any fds open continously.
This variable is not set by meson, so let's not try to use it.
We could use some more elaborate scheme (e.g. based on $MESON_BUILD_ROOT and
$MESON_SUBDIR) to find the path to systemd-sysv-generator, but it seems
that plain ./systemd-sysv-generator works just as well and has the advantage
that it's easy to invoke the test by hand (as long as one cd's to the
meson build dir).
Let's read one byte more than the file size we read from stat() on the
first fread() invocation. That way, the first read() will already be
short and indicate eof to fread().
This is a minor optimization, and replaces #3908.
LONG_LINE_MAX is much like LINE_MAX, but longer.
As it turns out LINE_MAX at 4096 is too short for many usecases. Since
the general concept of having a common maximum line length limit makes
sense let's add our own, and make it larger (1MB for now).
read_line() is much like getline(), and returns a line read from a
FILE*, of arbitrary sizes. In contrast to gets() it will grow the buffer
dynamically, and in contrast to getline() it will place a user-specified
boundary on the line.
Due to the chown() logic socket units might end up with processes even
if no explicit command is defined for them, hence let's make sure these
processes are in the right cgroup, and that means within a slice.
Mount, swap and service units unconditionally are assigned to a slice
already, let's do the same here, too.
(This becomes more important as soon as the ebpf/firewall stuff is
merged, as there'll be another reason to fork off processes then)
On cgroupsv2 we should also chown()/chmod() the subtree_control file,
so that children can use controllers the way they like.
On cgroupsv1 we should also chown()/chmod() cgroups.clone_children, as
not setting this for new cgroups makes little sense, and hence delegated
clients should be able to write to it.
Note that error handling for both cases is different. subtree_control
matters so we check for errors, but the clone_children/tasks stuff
doesn't really, as it's legacy stuff. Hence we only log errors and
proceed.
Fixes: #6216
These errors don't really matter, that's why we log and proceed in the
current code. However, we currently log at LOG_WARNING, but we really
shouldn't given that this is library code. Hence downgrade this to
LOG_DEBUG.
Lennart Poettering