let's use sd_notifyf(). Let's also stop validating the session ID here.
This is the destructor. if it contains a dash, we are already too late
here anyway.
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.
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.
This replaces commit 4d3900f1b7.
The underlying cause of issue #8291 has been fixed, so there is no reason
to paper over it any more.
But it might still be useful not to crash in the face of bad restart data.
That can cause several restarts, or maybe at some point an infinite loop
of restarts. Fail the start (or stop!) request, and write an error to the
system log. Each time reflects a user request where we fail to resume the
display server's access (or revoke it), and it can be useful if the log
shows the most recent one.
FDSTOREREMOVE=1 removes all fds with the specified name. And we had named
the fds after the session. Better fix that.
Closes#8344.
AFAICT there's no point providing compatibility code for this transition.
No-one would be restarting logind on a system with a GUI (where the
session devices are used), because doing so has been killing the GUI, and
even causing startup of the GUI to fail leading to a restart loop.
Upgrading logind on a running system with a GUI might start being possible
after this commit (and after also fixing the display server of your
choice).
We're not removing the pushed fd "again"; this is the only place
logind removes it from PID1. (And stopping the fd doesn't always
cause PID1 to remove the fd itself; it depends on the device type).
$ git grep FDNAME
logind-session-device.c: ... "FDNAME=session-", sd->session->id);
logind-session-device.c: ... "FDNAME=session", sd->session->id);
Oops.
Fixes#8343. Or at least a more minimal reproducer. Xorg still
dies when logind is restarted, but the Xorg message says this
is entirely deliberate.
(This could also be the reason I hit #8035, instead of the race
condition I originally suggested).
This patch ensures that session devices are saved for each session.
In order to make the revokation logic work when logind is restarted, the
session devices are now saved in the session state files and their respective
file descriptors sent to PID1's fdstore in order to keep them open accross
restart.
This is mandatory in order to keep the revokation logic working. Indeed in case
of input-devices, the same file descriptors must be shared by logind and a
given session controller in order EVIOCREVOKE to work otherwise multiple
sessions can have device access in parallel.
This should be the only remaining and missing piece for making logind fully
restartable.
Fixes: #1163
GLIB has recently started to officially support the gcc cleanup
attribute in its public API, hence let's do the same for our APIs.
With this patch we'll define an xyz_unrefp() call for each public
xyz_unref() call, to make it easy to use inside a
__attribute__((cleanup())) expression. Then, all code is ported over to
make use of this.
The new calls are also documented in the man pages, with examples how to
use them (well, I only added docs where the _unref() call itself already
had docs, and the examples, only cover sd_bus_unrefp() and
sd_event_unrefp()).
This also renames sd_lldp_free() to sd_lldp_unref(), since that's how we
tend to call our destructors these days.
Note that this defines no public macro that wraps gcc's attribute and
makes it easier to use. While I think it's our duty in the library to
make our stuff easy to use, I figure it's not our duty to make gcc's own
features easy to use on its own. Most likely, client code which wants to
make use of this should define its own:
#define _cleanup_(function) __attribute__((cleanup(function)))
Or similar, to make the gcc feature easier to use.
Making this logic public has the benefit that we can remove three header
files whose only purpose was to define these functions internally.
See #2008.
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.
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.
If the third argument is non-null, the kernel will always error out with
EINVAL and devices won't get revoked.
Reported-by: Benjamin Tissoires <benjamin.tissoires@gmail.com>
Signed-off-by: Peter Hutterer <peter.hutterer@who-t.net>
Previously the returned object of constructor functions where sometimes
returned as last, sometimes as first and sometimes as second parameter.
Let's clean this up a bit. Here are the new rules:
1. The object the new object is derived from is put first, if there is any
2. The object we are creating will be returned in the next arguments
3. This is followed by any additional arguments
Rationale:
For functions that operate on an object we always put that object first.
Constructors should probably not be too different in this regard. Also,
if the additional parameters might want to use varargs which suggests to
put them last.
Note that this new scheme only applies to constructor functions, not to
all other functions. We do give a lot of freedom for those.
Note that this commit only changes the order of the new functions we
added, for old ones we accept the wrong order and leave it like that.
Unfortunately, close() on a revoked/removed character-device fails with
ENODEV. I tried tracking this down in the kernel, but couldn't figure out
were exactly it comes from. However, can be easily reproduced with:
fd = open("/dev/input/event0", O_RDWR);
ioctl(fd, EVIOCREVOKE, 0);
r = close(fd);
A second close on @fd would return EBADF so the close is actually valid.
We simply ignore close() errors for all session-devices as their access
may be revoked asynchronously, or the device might get unplugged.
We use close_nointr() in case anyone ever looks at the return value (or
anyone runs "grep 'close(' -r src/" to find broken close() calls).
Fixes:
systemd-logind[31992]: Assertion 'close_nointr(fd) == 0' failed at src/shared/util.c:185, function close_nointr_nofail(). Aborting.
fbdev does not support access-handover so it is quite useless to route it
through logind. If compositors want to use it they ought to open it
themselves. It's highly recommended to be ignored entirely, though. fbdev
is about to be deprecated in the kernel.
The initial drmSetMaster may fail if there is an active master already. We
must not assume that all existing clients comply to logind rules. We check
for this during session-activation already but didn't during device setup.
Fix this by checking the return code.
As drmSetMaster has had horrible return codes in the past (0 for failure?
EINVAL for denied access, ..) we need to be quite pedantic. To guarantee
an open file-descriptor we need to close the device and reopen it without
master if setting master failed first.
Had this fix lying around here for some time. Thanks to missing
type-checking for va-args we passed in the actual major/minor values
instead of pointers to it. Fix it by saving the values on the stack first
and passing in the pointers.
Unfortunately on ARM-32 systems dev_t can be 64bit and thus we cannot
store it easily in void* keys for hashtables. Fix that by passing a
pointer to the dev_t variable instead.
This enables the multi-session capability for seats that don't have VTs.
For legacy seats with VTs, everything stays the same. However, all other
seats now also get the multi-session capability.
The only feature that was missing was session-switching. As logind can
force a session-switch and signal that via the "Active" property, we only
need a way to allow synchronized/delayed session switches. Compositors
need to cleanup some devices before acknowledging the session switch.
Therefore, we use the session-devices to give compositors a chance to
block a session-switch until they cleaned everything up.
If you activate a session on a seat without VTs, we send a PauseDevice
signal to the active session for every active device. Only once the
session acknowledged all these with a PauseDeviceComplete() call, we
perform the final session switch.
One important note is that delayed session-switching is meant for
backwards compatibility. New compositors or other sessions should really
try to deal correctly with forced session switches! They only need to
handle EACCES/EPERM from syscalls and treat them as "PauseDevice" signal.
Following logind patches will add a timeout to session-switches which
forces the switch if the active session does not react in a timely
fashion. Moreover, explicit ForceActivate() calls might also be supported.
Hence, sessions must not crash if their devices get paused.
Ben Boeckel