This is partially a refactoring, but also makes many more places use
unlocked operations implicitly, i.e. all users of fopen_temporary().
AFAICT, the uses are always for short-lived files which are not shared
externally, and are just used within the same context. Locking is not
necessary.
This splits out a bunch of functions from fileio.c that have to do with
temporary files. Simply to make the header files a bit shorter, and to
group things more nicely.
No code changes, just some rearranging of source files.
Ideally, coccinelle would strip unnecessary braces too. But I do not see any
option in coccinelle for this, so instead, I edited the patch text using
search&replace to remove the braces. Unfortunately this is not fully automatic,
in particular it didn't deal well with if-else-if-else blocks and ifdefs, so
there is an increased likelikehood be some bugs in such spots.
I also removed part of the patch that coccinelle generated for udev, where we
returns -1 for failure. This should be fixed independently.
Basically when a session ends, logind notices and restores VT_AUTO so the
kernel takes back VT-switching over.
logind achieves that by watching the process that took control of the session
(via the "TakeControl" D-Bus method), aka "the watched process", which can
be different from the one that initially opened the VT aka "the terminal
controlling process".
In this case the terminal controlling process can exit after the watched one
did and while logind is restoring the VT.
Even if logind took care to re-open the VT in case the VT was already in HUP
state, it wasn't enough because the terminal controlling process could have
exited right after, leaving the VT in HUP state and in VT_PROCESS mode making
further VT-switching impossible.
This patch fixes this situation by forcing logind to become the terminal
controlling process.
Fixes: #9754.
Now that we don't (mis-)use the env file parser to parse kernel command
lines there's no need anymore to override the used newline character
set. Let's hence drop the argument and just "\n\r" always. This nicely
simplifies our code.
Let's be more careful with what we serialize: let's ensure we never
serialize strings that are longer than LONG_LINE_MAX, so that we know we
can read them back with read_line(…, LONG_LINE_MAX, …) safely.
In order to implement this all serialization functions are move to
serialize.[ch], and internally will do line size checks. We'd rather
skip a serialization line (with a loud warning) than write an overly
long line out. Of course, this is just a second level protection, after
all the data we serialize shouldn't be this long in the first place.
While we are at it also clean up logging: while serializing make sure to
always log about errors immediately. Also, (void)ify all calls we don't
expect errors in (or catch errors as part of the general
fflush_and_check() at the end.
This is useful so that during shutdown scope units are always terminated
before the mounts necessary for the home directory.
(Ideally we'd also add a similar dependency from the user@.service
instance to the home directory, but this isn't as easy as that service
is defined statically and not dynamically, and hence not easy to modify
dynamically, in particular when it comes to deps)
Instead of managing it explicitly, let's simplify things and rely on
regular Wants=/Requires= dependencies to pull in these units from
user@.service and the session scope, and StopWhenUneeded= to stop these
auxiliary units again. This way, they can be pulled in easily by
unrelated units too.
This simplifies things quite a bit: for each session we now only need to
manage the session scope, and for each user the user@.service, the other
units are not something we need to manage anymore.
This patch also makes sure that if user@.service of a user is masked we
will continue to work, and user-runtime-dir@.service will still be
correctly pulled in, as it is now a dependency of the scope unit.
Fixes: #9461
Replaces: #5546
Previously this was serialized as part of the user object. This didn't
work however, as we load users first, and sessions seconds and hence
referencing a session from the user load logic cannot work.
Fix this by storing an IS_DISPLAY property along with each session, and
make the session with this set display session when it is loaded.
Let's update things a bit to follow current practices:
- User structure initialization rather than zero-initialized allocation
- Always propagate proper errors from allocation functions
- Use _cleanup_ for freeing objects when allocation fails half-way
- Make destructors return NULL
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.
Let's show a message at the time of logout i.e. entering the "closing"
state, not just e.g. once the user closes `tmux` and the session can be
removed completely. (At least when KillUserProcesses=no applies. My
thinking was we can spare the log noise if we're killing the processes
anyway).
These are two independent events. I think the logout event is quite
significant in the session lifecycle. It will be easier for a user who
does not know logind details to understand why "Removed session" doesn't
appear at logout time, if we have a specific message we can show at this
time :).
Tested using tmux and KillUserProcesses=no. I can also confirm the extra
message doesn't show when using KillUserProcesses=yes. Maybe it looks a
bit mysterious when you use KillOnlyUsers= / KillExcludeUsers=, but
hopefully not alarmingly so.
I was looking at systemd-logind messages on my system, because I can
reproduce two separate problems with Gnome on Fedora 28 where
sessions are unexpectedly in state "closing". (One where a GUI session
limps along in a degraded state[1], and another where spice-vdagent is left
alive after logout, keeping the session around[2]). It logged when
sessions were created and removed, but it didn't log when the session
entered the "closing" state.
[1] https://bugzilla.redhat.com/show_bug.cgi?id=1583240#c1
[2] https://bugzilla.redhat.com/show_bug.cgi?id=1583261Closes#9096
Most our other parsing functions do this, let's do this here too,
internally we accept that anyway. Also, the closely related
load_env_file() and load_env_file_pairs() also do this, so let's be
systematic.
Double newlines (i.e. one empty lines) are great to structure code. But
let's avoid triple newlines (i.e. two empty lines), quadruple newlines,
quintuple newlines, …, that's just spurious whitespace.
It's an easy way to drop 121 lines of code, and keeps the coding style
of our sources a bit tigther.
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.
When we are attempting to create directory somewhere in the bowels of /var/lib
and get an error that it already exists, it can be quite hard to diagnose what
is wrong (especially for a user who is not aware that the directory must have
the specified owner, and permissions not looser than what was requested). Let's
print a warning in most cases. A warning is appropriate, because such state is
usually a sign of borked installation and needs to be resolved by the adminstrator.
$ build/test-fs-util
Path "/tmp/test-readlink_and_make_absolute" already exists and is not a directory, refusing.
(or)
Directory "/tmp/test-readlink_and_make_absolute" already exists, but has mode 0775 that is too permissive (0755 was requested), refusing.
(or)
Directory "/tmp/test-readlink_and_make_absolute" already exists, but is owned by 1001:1000 (1000:1000 was requested), refusing.
Assertion 'mkdir_safe(tempdir, 0755, getuid(), getgid(), MKDIR_WARN_MODE) >= 0' failed at ../src/test/test-fs-util.c:320, function test_readlink_and_make_absolute(). Aborting.
No functional change except for the new log lines.
This is similar to TAKE_PTR() but operates on file descriptors, and thus
assigns -1 to the fd parameter after returning it.
Removes 60 lines from our codebase. Pretty good too I think.
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)
Apparently O_NONBLOCK is the modern name used in most documentation and
for most cases in our sources. Let's hence replace the old alias
O_NDELAY and stick to O_NONBLOCK everywhere.