I'm working on the transition to merged sbin in Fedora. While the transition is
happening (and probably for a while after), we need to compile systemd with
split-bin=true to support systems upgraded from previous versions. But when the
system has been upgraded and already has /usr/sbin that is a symlink, be nice
and give $PATH without sbin.
We check for both /usr/sbin and /usr/local/sbin. If either exists and is not a
symlink to ./bin, we retain previous behaviour. This means that if both are
converted, we get the same behaviour as split-bin=false, and otherwise we
get the same behaviour as before.
sd-path uses the same logic. This is not a hot path, so I got rid of the nulstr
macros that duplicated the logic.
path_simplify_full()/path_simplify() are changed to allow a NULL path, for
which a NULL is returned. Generally, callers have already asserted before that
the argument is nonnull. This way path_simplify_full()/path_simplify() and
path_simplify_alloc() behave consistently.
In sd-device.c, logging in device_set_syspath() is intentionally dropped: other
branches don't log.
In mount-tool.c, logging in parse_argv() is changed to log the user-specified
value, not the simplified string. In an error message, we should show the
actual argument we got, not some transformed version.
I.e., /.. becomes /, /../foo becomes /foo, /../../bar becomes /bar, etc. We can
do this unconditionally, without access to the file system, because the parent
of the root directory always resolves to. /.. in other places is handled as
before, because resolving it properly would require access to the file system
which we don't want to do in path_simplify().
"/dev" or "/dev/" is the mount point, not a device path. In particular,
'systemctl status /dev' clearly does not refer to a device, so let's tweak
the code a bit to say that those are not device paths.
(Treating "/../dev" same as "/dev" would be also be reasonable, but that
requires chase(), which requires disk access, which we don't want to do from
this lightweight function.)
Add a helper filename_part_is_valid() which does half of what
filename_is_valid() does: it checks for valid chars and length, but does
not filter out ".", ".." and "", as these are OK as parts of filenames,
just not alone.
Let's be more accurate about what this function does: it checks whether
the underlying reported inode is the same. Internally, this already uses
a better named stat_inode_same() call, hence let's similarly name the
wrapping function following the same logic.
Similar for files_same_at() and path_equal_or_same_files().
No code changes, just some renaming.
The function path_prefix_root_cwd() was introduced for prefixing the
result from chaseat() with root, but
- it is named slightly generic,
- the logic is different from what chase() does.
This makes the name more explanative and specific for the result of the
chaseat(), and make the logic consistent with chase().
Fixes https://github.com/systemd/systemd/pull/27199#issuecomment-1511387731.
Follow-up for #27199.
Chasing symlinks is a core function that's used in a lot of places
so it deservers a less verbose names so let's rename it to chase()
and chaseat().
We also slightly change the pattern used for the chaseat() helpers
so we get chase_and_openat() and similar.
Let's port one more over.
Note that this changes behaviour of file_in_same_dir() in some regards.
Specifically, a trailing slash of the input path will be treated
differently: previously we'd operate below that dir then, instead of the
parent. I think that makes little sense however, and I think the code
using this function doesn't expect that either.
Moroever, addresses some corner cases if the path is specified as "/" or
".", i.e. where e cannot extract a parent. These will now be treated as
error, which I think is much cleaner.
-1 was used everywhere, but -EBADF or -EBADFD started being used in various
places. Let's make things consistent in the new style.
Note that there are two candidates:
EBADF 9 Bad file descriptor
EBADFD 77 File descriptor in bad state
Since we're initializating the fd, we're just assigning a value that means
"no fd yet", so it's just a bad file descriptor, and the first errno fits
better. If instead we had a valid file descriptor that became invalid because
of some operation or state change, the other errno would fit better.
In some places, initialization is dropped if unnecessary.
This is useful for systems which don't have any fsck.
We already skip emitting the fsck dependency when the fsck.$fstype helper
is missing, but fstab-generator doesn't necessarily know the fstype when
handling the root= parameter.
Previously, systemd-fsck was started for these mounts and then exited
immediately because it couldn't find the fsck.$fstype helper.
This is a high-level function, and it belongs in libsystemd-shared. This way we
don't end up linking a separate copy into various binaries. It would even end
up in libsystemd, where it is not needed. (Maybe it'd be removed in some
optimization phase, but it's better to not rely on that.)
$ grep -l -r -a 'path is not absolute%s' build/
build/libnss_systemd.so.2
build/pam_systemd_home.so
build/test-dlopen
build/src/basic/libbasic.a.p/path-util.c.o
build/src/basic/libbasic.a
build/src/shared/libsystemd-shared-249.so
build/test-bus-error
build/libnss_mymachines.so.2
build/pam_systemd.so
build/libnss_resolve.so.2
build/libnss_myhostname.so.2
build/libsystemd.so.0.32.0
build/libudev.so.1.7.2
$ grep -l -r -a 'path is not absolute%s' build/
build/src/shared/libsystemd-shared-251.a.p/parse-helpers.c.o
build/src/shared/libsystemd-shared-251.a
build/src/shared/libsystemd-shared-251.so
No functional change.
This function implements a heuristic that is only used by nspawn. It doesn't
belong in basic. I opted for a new file "nspawn-utils.c", because it seems
likely that we'll need some other new utilities like that in the future.
No functional change.
The three functions for reading cwd, exe and root symlinks of processes
already share a common core: get_process_link_contents(). Let's refactor
that a bit, and move formatting of the /proc/self/ path into this helper
function instead of doing that in the caller, thus sharing more code.
While we are at it, make the return parameters optional, in case the
information if the links are readable is interesting, but the contents
is not. (This also means safe_getcwd() and readlinkat_malloc() are
updated to make the return parameter optional, as these are called by
the relevant three functions)
Currently there does not exist a way to specify a path relative to which
all binaries executed by Exec should be found. The only way is to
specify the absolute path.
This change implements the functionality to specify a path relative to which
binaries executed by Exec*= can be found.
Closes#6308
When the root parameter in find_executable_full is set, chase_symlinks prefixes this root
to every check of the path name to find the complete path of the execuatble in case the
path provided is not absolute. This is only done for the non NULL root because otherwise
the chase_symlinks function would alter the behavior of some of the callers which would
in turn alter the outputs in a way that is undesirable. The find_execuatble_full function is
invoked by the verify_executable function in analyze-verify.
