%c and %r rely on settings made in the unit files themselves and hence resolve
to different values depending on whether they are used before or after Slice=.
Let's simply deprecate them and drop them from the documentation, as that's not
really possible to fix. Moreover they are actually redundant, as the same
information may always be queried from /proc/self/cgroup and /proc/1/cgroup.
(Accurately speaking, %R is actually not broken like this as it is constant.
However, let's remove all cgroup-related specifiers at once, as it is also
redundant, and doesn't really make much sense alone.)
Let's permit specifier expansion at a numbre of additional fields, where
arbitrary strings might be passed where this might be useful one day. (Or at
least where there's no clear reason where it wouldn't make sense to have.)
For settings that are not taking unit names there's no reason to use
unit_name_printf(). Use unit_full_printf() instead, as the names are validated
anyway in one form or another after expansion.
unit_name_printf() is usually what we use when the resulting string shall
qualify as unit name, and it hence avoids resolving specifiers that almost
certainly won't result in valid unit names.
Add a couple of more specifiers that unit_full_printf() resolves also to the
list unit_name_printf() resolves, as they are likely to be useful in valid unit
names too. (Note that there might be cases where this doesn't hold, but we
should still permit this, as more often than not they are safe, and if people
want to use them that way, they should be able to.)
This monopolizes unit file specifier expansion in load-fragment.c, and removes
it from socket.c + service.c. This way expansion becomes an operation done exclusively at time of loading unit files.
Previously specifiers were resolved for all settings during loading of unit
files with the exception of ExecStart= and friends which were resolved in
socket.c and service.c. With this change the latter is also moved to the
loading of unit files.
Fixes: #3061
Let's accept "µs" as alternative time unit for microseconds. We already accept
"us" and "usec" for them, lets extend on this and accept the proper scientific
unit specification too.
We will never output this as time unit, but it's fine to accept it, after all
we are pretty permissive with time units already.
When we are in link_enter_configured we assume that the
link->state should be LINK_STATE_SETTING_ROUTES but in some
situation it's LINK_STATlE_SETTING_ADDRESSES.
Just ignore the wrong state.
Also since the return value not used any where
make link_enter_configured return type void.
Fixes: #4746
Make sure to populate the cache in cache_space_refresh() at least once
otherwise it's possible that the system boots fast enough (and the journal
flush service is finished) before the invalidate cache timeout (30 us) has
expired.
Fixes: #4790
It is possible to specify only one quote in udev rules, which is not
detected as an invalid quoting (" instead of "" for empty string).
Technically this doesn't lead to a bug, because the string ends in two
terminating nul characters at this position, but a user should still be
reminded that his configuration is invalid.
This extends the --bind= and --overlay= syntax so that an empty string as source/upper
directory is taken as request to automatically allocate a temporary directory
below /var/tmp, whose lifetime is bound to the nspawn runtime. In combination
with the "+" path extension this permits a switch "--overlay=+/var::/var" in
order to use the container's shipped /var, combine it with a writable temporary
directory and mount it to the runtime /var of the container.
If a source path is prefixed with "+" it is taken relative to the container's
root directory instead of the host. This permits easily establishing bind and
overlay mounts based on data from the container rather than the host.
This also reworks custom_mounts_prepare(), and turns it into two functions: one
custom_mount_check_all() that remains in nspawn.c but purely verifies the
validity of the custom mounts configured. And one called
custom_mount_prepare_all() that actually does the preparation step, sorts the
custom mounts, resolves relative paths, and allocates temporary directories as
necessary.
If --template= is used on an image, then the image might not exist initially.
We can use CHASE_NON_EXISTING to properly lock the image already before it
exists. Let's do so.
This new flag controls whether to consider a problem if the referenced path
doesn't actually exist. If specified it's OK if the final file doesn't exist.
Note that this permits one or more final components of the path not to exist,
but these must not contain "../" for safety reasons (or, to be extra safe,
neither "./" and a couple of others, i.e. what path_is_safe() permits).
This new flag is useful when resolving paths before issuing an mkdir() or
open(O_CREAT) on a path, as it permits that the file or directory is created
later.
The return code of chase_symlinks() is changed to return 1 if the file exists,
and 0 if it doesn't. The latter is only returned in case CHASE_NON_EXISTING is
set.
Let's remove chase_symlinks_prefix() and instead introduce a flags parameter to
chase_symlinks(), with a flag CHASE_PREFIX_ROOT that exposes the behaviour of
chase_symlinks_prefix().
Previously, we'd generate an EINVAL error if it is attempted to escape a root
directory with relative ".." symlinks. With this commit this is changed so that
".." from the root directory is a NOP, following the kernel's own behaviour
where /.. is equivalent to /.
As suggested by @keszybz.
chase_symlinks() currently expects a fully qualified, absolute path, relative
to the host's root as first argument. Which is useful in many ways, and similar
to the paths unlink(), rename(), open(), … expect. Sometimes it's however
useful to first prefix the specified path with the specified root directory.
Add a new call chase_symlinks_prefix() for this, that is a simple wrapper.
As suggested in PR #3667.
This PR simply ensures that --template= can be used as alternative to
--directory= when --ephemeral is used, following the logic that for ephemeral
options the source directory is actually a template.
This does not deprecate usage of --directory= with --ephemeral, as I am not
convinced the old logic wouldn't make sense.
Fixes: #3667
This resolves any paths specified on --directory=, --template=, and --image=
before using them. This makes sure nspawn can be used correctly on symlinked
images and directory trees.
Fixes: #2001
Let's use chase_symlinks() everywhere, and stop using GNU
canonicalize_file_name() everywhere. For most cases this should not change
behaviour, however increase exposure of our function to get better tested. Most
importantly in a few cases (most notably nspawn) it can take the correct root
directory into account when chasing symlinks.
We generally try to make our destructors robust regarding NULL pointers, much
in the same way as glibc's free(). Do this also for unit_free().
Follow-up for #4748.
