This enum should be used to define various idmapping modes for bind
mounts which might be incompatible. Changing its name and the values
name to reflect that.
systemd-growfs currently requires that udev ran first to work (because
/dev/block/ symlinks must exist) but that is not what happens when
we're not using initrd and systemd is PID1.
If the delta specified is INT64_MIN, and we negate that we'd end up at
INT64_MAX+1 which is outside of the int64_t type. Hence let's treat this
case specifically to avoid unintended overflows.
The check of u==UID_NOBODY is just a register comparison, but
synthesize_nobody() requires a system call, so let's invert the order in the
condition. Since most calls into this module are not for nobody, we should
save one syscall in the common case.
/bin/sh as a shell is punishing. There is no good reason to make
the occasional root login unpleasant.
Since /bin/sh is usually /bin/bash in compat mode, i.e. if one is
available, the other will be too, /bin/bash is almost as good as a default.
But to avoid a regression in the situation where /bin/bash (or
DEFAULT_USER_SHELL) is not installed, we check with access() and fall back
to /bin/sh. This should make this change in behaviour less risky.
(FWIW, e.g. Fedora/RHEL use /bin/bash as default for root.)
This is a follow-up of sorts for 53350c7bba,
which added the default-user-shell option, but most likely with the idea
of using /bin/bash less ;)
Fixes#24369.
Otherwise it complains about a set but unused variable:
```
../src/basic/hashmap.c:1070:48: error: variable 'n_rehashed' set but not used [-Werror,-Wunused-but-set-variable]
unsigned old_n_buckets, new_n_buckets, n_rehashed, new_n_entries;
^
1 error generated.
```
Previously it was possible to set delegate property for scope, but you
were not able to allow unprivileged process to manage the scope's cgroup
hierarchy. This is useful when launching manager process that will run
unprivileged but is supposed to manage its own (scope) sub-hierarchy.
Fixes#21683
Inspired by: https://github.com/systemd/systemd/pull/24141
Calling fd_is_mountpoint() with AT_EMPTYPATH and an empty filename can
only work if we have new statx() available. If we do not, we can still
make things work for directories, but not for other inodes (since there
we cannot query information about the parent inode to compare things.)
Hence, let's handle and test this explicitly, to support this to the
level this is possible.