When we would iterate over the lookup paths for each unit, making the list as
short as possible was important for performance. With the current cache, it
doesn't matter much. Two classes of paths were being removed:
- paths which don't exist in the filesystem
- paths which symlink to a path earlier in the search list
Both of those points cause problems with the caching code:
- if a user creates a directory that didn't exist before and puts units there,
now we will notice the new mtime an properly load the unit. When the path
was removed from list, we wouldn't.
- we now properly detect whether a unit path is on the path or not.
Before, if e.g. /lib/systemd/system, /usr/lib/systemd/systemd were both on
the path, and /lib was a symlink to /usr/lib, the second directory would be
pruned from the path. Then, the code would think that a symlink
/etc/systemd/system/foo.service→/lib/systemd/system/foo.service is an alias,
but /etc/systemd/system/foo.service→/usr/lib/systemd/system/foo.service would
be considered a link (in the systemctl link sense).
Removing the pruning has a slight negative performance impact in case of
usr-merge systems which have systemd compiled with non-usr-merge paths.
Non-usr-merge systems are deprecated, and this impact should be very small, so
I think it's OK. If it turns out to be an issue, the loop in function that
builds the cache could be improved to skip over "duplicate" directories with
same logic that the cache pruning did before. I didn't want to add this,
becuase it complicates the code to improve a corner case.
Fixes#13272.
When $XDG_DATA_DIRS is unset, then, the default value
'/usr/local/share:/usr/share' is used.
When $XDG_DATA_DIRS contain the default paths but the order
is inverted: '/usr/share:/usr/local/share', then test-path-lookup fails.
Fixes#10002.
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.
This drops a good number of type-specific _cleanup_ macros, and patches
all users to just use the generic ones.
In most recent code we abstained from defining type-specific macros, and
this basically removes all those added already, with the exception of
the really low-level ones.
Having explicit macros for this is not too useful, as the expression
without the extra macro is generally just 2ch wider. We should generally
emphesize generic code, unless there are really good reasons for
specific code, hence let's follow this in this case too.
Note that _cleanup_free_ and similar really low-level, libc'ish, Linux
API'ish macros continue to be defined, only the really high-level OO
ones are dropped. From now on this should really be the rule: for really
low-level stuff, such as memory allocation, fd handling and so one, go
ahead and define explicit per-type macros, but for high-level, specific
program code, just use the generic _cleanup_() macro directly, in order
to keep things simple and as readable as possible for the uninitiated.
Note that before this patch some of the APIs (notable libudev ones) were
already used with the high-level macros at some places and with the
generic _cleanup_ macro at others. With this patch we hence unify on the
latter.
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.
It's not good if the paths are in different order. With --user, we expect
more paths, but it must be a strict superset, and the order for the ones
that appear in both sets must be the same.
$ diff -u <(build/systemd-analyze --global unit-paths) <(build/systemd-analyze --user unit-paths)|colordiff
--- /proc/self/fd/14 2018-02-08 14:11:45.425353107 +0100
+++ /proc/self/fd/15 2018-02-08 14:11:45.426353116 +0100
@@ -1,6 +1,17 @@
+/home/zbyszek/.config/systemd/system.control
+/run/user/1000/systemd/system.control
+/run/user/1000/systemd/transient
+/run/user/1000/systemd/generator.early
+/home/zbyszek/.config/systemd/user
/etc/systemd/user
+/run/user/1000/systemd/user
/run/systemd/user
+/run/user/1000/systemd/generator
+/home/zbyszek/.local/share/systemd/user
+/home/zbyszek/.local/share/flatpak/exports/share/systemd/user
+/var/lib/flatpak/exports/share/systemd/user
/usr/local/share/systemd/user
/usr/share/systemd/user
/usr/local/lib/systemd/user
/usr/lib/systemd/user
+/run/user/1000/systemd/generator.late
A test is added so that we don't regress on this.
The SysV compat code checks whether there's a native unit file before looking
for a SysV init script. Since the newest rework generated units will show up in
the unit path, and hence the checks ended up assuming that there always was a
native unit file for each init script: the generated one.
With this change the generated unit file directory is suppressed from the
search path when this check is done, to avoid the confusion.
This is too confusing, as this funciton returns the paths to the generator
binaries, while usually when we refer to the just the "generator path" we mean
the generated unit files. Let's clean this up.
Previously, we had two enums ManagerRunningAs and UnitFileScope, that were
mostly identical and converted from one to the other all the time. The latter
had one more value UNIT_FILE_GLOBAL however.
Let's simplify things, and remove ManagerRunningAs and replace it by
UnitFileScope everywhere, thus making the translation unnecessary. Introduce
two new macros MANAGER_IS_SYSTEM() and MANAGER_IS_USER() to simplify checking
if we are running in one or the user context.
A long time ago – when generators where first introduced – the directories for
them were randomly created via mkdtemp(). This was changed later so that they
use fixed name directories now. Let's make use of this, and add the genrator
dirs to the LookupPaths structure and into the unit file search path maintained
in it. This has the benefit that the generator dirs are now normal part of the
search path for all tools, and thus are shown in "systemctl list-unit-files"
too.
There are more than enough calls doing string manipulations to deserve
its own files, hence do something about it.
This patch also sorts the #include blocks of all files that needed to be
updated, according to the sorting suggestions from CODING_STYLE. Since
pretty much every file needs our string manipulation functions this
effectively means that most files have sorted #include blocks now.
Also touches a few unrelated include files.
It's primarily just a property of the Manager object after all, and we
try to refer to PID 1 as "manager" instead of "systemd", hence let's to
stick to this here too.
This patch removes includes that are not used. The removals were found with
include-what-you-use which checks if any of the symbols from a header is
in use.
After all it is now much more like strjoin() than strappend(). At the
same time, add support for NULL sentinels, even if they are normally not
necessary.
