Apparently CMSG_DATA() alignment is very much undefined. Which is quite
an ABI fuck-up, but we need to deal with this. CMSG_TYPED_DATA() already
checks alignment of the specified pointer. Let's also check matching
alignment of the underlying structures, which we already can do at
compile-time.
See: #27241
(This does not fix#27241, but should catch such errors already at
compile-time instead of runtime)
Oftentimes it is useful to allow the per-service fd store to survive
longer than for a restart. This is useful in various scenarios:
1. An fd to some security relevant object needs to be stashed somewhere,
that should not be cleaned automatically, because the security
enforcement would be dropped then.
2. A user namespace fd should be allocated on first invocation and be
kept around until the user logs out (i.e. systemd --user ends), á la
#16328 (This does not implement what #16318 asks for, but should
solve the use-case discussed there.)
3. There's interest in allow a concept of "userspace reboots" where the
kernel stays running, and userspace is swapped out (i.e. all services
exit, and the rootfs transitioned into a new version of it) while
keeping some select resources pinned, very similar to how we
implement a switch root. Thus it is useful to allow services to exit,
while leaving their fds around till the very end.
This is exposed through a new FileDescriptorStorePreserve= setting that
is closely modelled after RuntimeDirectoryPreserve= (in fact it reused
the same internal type), since we want similar behaviour in the end, and
quite often they probably want to be used together.
The Upholds= promise is that as long as unit A is up and Upholds=B,
B will be activated if failed or inactive. But there is a hard-coded,
non-configurable rate limit for this, so add a timed retry after the
ratelimit has expired.
Apply to BindsTo= and StopWhenUnneeded= as well.
To make it consistent with other env vars, e.g. $SYSTEMD_ESP_PATH or
$SYSTEMD_XBOOTLDR_PATH.
This is useful when the root is specified by a file descriptor, instead
of a path.
For consistency with other functions.
Unfortunately, va_start() requires that the previous argument is a
pointer, hence the order of the arguments in the internal function
cannot be changed.
The variable 'r' is usually used for storing return value of functional
call. Let's introduce another boolean to store the current loop status.
No functional change, just refactoring.
In that branch, 'root' is a non-root and absolute path.
Hence, delete_trailing_chars() does not make the path empty.
And, if the path contains redundant slashes at the end, that will be
dropped by path_simplify().
When extension is not specified, image class is not necessary to be
specified. Let's use _IMAGE_CLASS_INVALID as an indicator that no
extension is specified.
Previously, struct stat may not be correctly synced with the currently
opened fd, e.g. when a path contains symlink which points to an absolute
path.
This also rename variables for struct stat, to make them consistent with
the corresponding fd.
Yu Watanabe
Luca Boccassi
OMOJOLA JOSHUA DAMILOLA
Lennart Poettering
Daan De Meyer
Zbigniew Jędrzejewski-Szmek