We allocated the names set for each unit, but in the majority of cases, we'd
put only one name in the set:
$ systemctl show --value -p Names '*'|grep .|grep -v ' '|wc -l
564
$ systemctl show --value -p Names '*'|grep .|grep ' '|wc -l
16
So let's add a separate .id field, and only store aliases in the set, and only
create the set if there's at least one alias. This requires a bit of gymnastics
in the code, but I think this optimization is worth the trouble, because we
save one object for many loaded units.
In particular set_complete_move() wasn't very useful because the target
unit would always have at least one name defined, i.e. the optimization to
move the whole set over would never fire.
It had two users, but it is just a very thin wrapper around
unit_file_find_dropin_paths(), so using it seems more complicated than directly
invoking unit_file_find_dropin_paths() twice.
This part of the copyright blurb stems from the GPL use recommendations:
https://www.gnu.org/licenses/gpl-howto.en.html
The concept appears to originate in times where version control was per
file, instead of per tree, and was a way to glue the files together.
Ultimately, we nowadays don't live in that world anymore, and this
information is entirely useless anyway, as people are very welcome to
copy these files into any projects they like, and they shouldn't have to
change bits that are part of our copyright header for that.
hence, let's just get rid of this old cruft, and shorten our codebase a
bit.
Files which are installed as-is (any .service and other unit files, .conf
files, .policy files, etc), are left as is. My assumption is that SPDX
identifiers are not yet that well known, so it's better to retain the
extended header to avoid any doubt.
I also kept any copyright lines. We can probably remove them, but it'd nice to
obtain explicit acks from all involved authors before doing that.
Essentially, instead of sequentially adding deps based on all symlinks
encountered in .wants and .requires dirs for each name and each unit file load
path, iteratate over the load paths and unit names gathering symlinks, then
order them based on priority, and then iterate over the final list, adding
dependencies.
This patch doesn't change the logic too much, except that the order in which
dependencies are applied might be different. It wasn't defined before, so that
not really a change. Adding filtering on the symlinks is left for later
patches.
The general rule is:
- code in shared/ should take an "original_root" argument (possibly NULL)
and pass it along down to chase_symlinks
- code in core/ should always use specify original_root==NULL, since we
don't support running the manager from non-root directory
- code in systemctl and other tools should pass arg_root.
For any code that is called from tools which support --root, chase_symlinks
must be used to look up paths.
Instead of adjusting job timeouts in the core, let fstab-generator
write out a dropin snippet with the appropriate JobTimeout.
x-systemd-device.timeout option is removed from Options= line
in the generated unit.
The functions to write dropins are moved from core/unit.c to
shared/dropin.c, to make them available outside of core.
generator.c is moved to libsystemd-label, because it now uses
functions defined in dropin.c, which are in libsystemd-label.
Yu Watanabe