As described in #15603, it is a fairly common setup to use a fqdn as the
configured hostname. But it is often convenient to use just the actual
hostname, i.e. until the first dot. This adds support in tmpfiles, sysusers,
and unit files for %l which expands to that.
Fixes#15603.
It would be very wrong if any of the specfier printf calls modified
any of the objects or data being printed. Let's mark all arguments as const
(primarily to make it easier for the reader to see where modifications cannot
occur).
These lines are generally out-of-date, incomplete and unnecessary. With
SPDX and git repository much more accurate and fine grained information
about licensing and authorship is available, hence let's drop the
per-file copyright notice. Of course, removing copyright lines of others
is problematic, hence this commit only removes my own lines and leaves
all others untouched. It might be nicer if sooner or later those could
go away too, making git the only and accurate source of authorship
information.
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 corresponds nicely with the specifiers we already pass for
/var/lib, /var/cache, /run and so on.
This is particular useful to update the test-path service files to
operate without guessable files, thus allowing multiple parallel
test-path invocations to pass without issues (the idea is to set $TMPDIR
early on in the test to some private directory, and then only use the
new %T or %V specifier to refer to it).
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.
This is a separate commit only because it actually *increases* memory allocations:
==3256== total heap usage: 100,120 allocs, 100,120 frees, 13,097,140 bytes allocated
to
==4690== total heap usage: 100,121 allocs, 100,121 frees, 14,198,329 bytes allocated
Essentially, we do a little more work to reduce the memory footprint a bit. For a
test where we just allocate the memory and drop it soon afterwards, this is not
beneficial, but it should still be useful for a long running program.
ubsan times out because we do too many allocations:
$ valgrind build/fuzz-unit-file test/fuzz-regressions/fuzz-unit-file/oss-fuzz-6977-full
...
test/fuzz-regressions/fuzz-unit-file/oss-fuzz-6977-full... ok
==1757==
==1757== HEAP SUMMARY:
==1757== in use at exit: 0 bytes in 0 blocks
==1757== total heap usage: 199,997 allocs, 199,997 frees, 90,045,318,585 bytes allocated
...
==3256== total heap usage: 100,120 allocs, 100,120 frees, 13,097,140 bytes allocated
https://oss-fuzz.com/v2/issue/4651449704251392/6977 should now be really fixed.
e3c3d6761b was the first attempt, but even with this change, e3c3d6761b
still makes sense.
This macro will read a pointer of any type, return it, and set the
pointer to NULL. This is useful as an explicit concept of passing
ownership of a memory area between pointers.
This takes inspiration from Rust:
https://doc.rust-lang.org/std/option/enum.Option.html#method.take
and was suggested by Alan Jenkins (@sourcejedi).
It drops ~160 lines of code from our codebase, which makes me like it.
Also, I think it clarifies passing of ownership, and thus helps
readability a bit (at least for the initiated who know the new macro)
```
$ ./src/test/test-systemd-tmpfiles.py valgrind --leak-check=full --error-exitcode=1 ./build/systemd-tmpfiles
...
Running valgrind --leak-check=full --error-exitcode=1 ./build/systemd-tmpfiles on 'w /unresolved/argument - - - - "%Y"'
...
[<stdin>:1] Failed to substitute specifiers in argument: Invalid slot
...
==22602== 5 bytes in 1 blocks are definitely lost in loss record 1 of 2
==22602== at 0x4C2DB8F: malloc (in /usr/lib/valgrind/vgpreload_memcheck-amd64-linux.so)
==22602== by 0x4ECA7D4: malloc_multiply (alloc-util.h:74)
==22602== by 0x4ECA909: specifier_printf (specifier.c:59)
==22602== by 0x113490: specifier_expansion_from_arg (tmpfiles.c:1923)
==22602== by 0x1144E7: parse_line (tmpfiles.c:2159)
==22602== by 0x11551C: read_config_file (tmpfiles.c:2425)
==22602== by 0x115AB0: main (tmpfiles.c:2529)
```
The code intentionally ignored unknown specifiers, treating them as text. This
needs to change because otherwise we can never add a new specifier in a backwards
compatible way. So just treat an unknown (potential) specifier as an error.
In principle this is a break of backwards compatibility, but the previous
behaviour was pretty much useless, since the expanded value could change every
time we add new specifiers, which we do all the time.
As a compromise for backwards compatibility, only fail on alphanumerical
characters. This should cover the most cases where an unescaped percent
character is used, like size=5% and such, which behave the same as before with
this patch. OTOH, this means that we will not be able to use non-alphanumerical
specifiers without breaking backwards compatibility again. I think that's an
acceptable compromise.
v2:
- add NEWS entry
v3:
- only fail on alphanumerical
The code in install-printf.c and unit-printf.c for these is pretty much
the same and very generic. Let's move this all over to the generic
specifier.c, and share the implementations.
Current behavior is that %X where X is an unidentified specifier, then the result is
the same %X string. This was not the case when the string ended with a stray %, where
the character would have not been output. Lets add that missing character.
Fixes: #6374
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.
Previously the specifier calls could only indicate OOM by returning
NULL. With this change they will return negative errno-style error codes
like everything else.
Yu Watanabe