Imagine a constructor like this:
int object_new(void **out) {
void *my_object;
int r;
...
r = ioctl(...);
if (r < 0)
return -errno;
...
*out = my_object;
return 0;
}
We have a lot of those in systemd. If you now call those, gcc might inline
the call and optimize it. However, gcc cannot know that "errno" is
negative if "r" is. Therefore, a caller like this will produce warnings:
r = object_new(&obj);
if (r < 0)
return r;
obj->xyz = "foobar";
In case the ioctl in the constructor fails, gcc might assume "errno" is 0
and thus the error-handling is not triggered. Therefore, "obj" is
uninitialized, but accessed. Gcc will warn about that.
The new negative_errno() helper can be used to mitigate those warnings.
The helper is guaranteed to return a negative integer. Furthermore, it
spills out runtime warnings if "errno" is non-negative.
Instead of returning "-errno", you can use:
return negative_errno();
gcc will no longer assume that this can return >=0, thus, it will not warn
about it.
Use this new helper in libsystemd-terminal to fix some grdev-drm warnings.
Function queries system hostname and applies changes only when necessary. Also,
migrate all client of sethostname to sethostname_idempotent while at it.
Lets not unnecessarily rely on __WORDSIZE, which is not clearly specified
by any spec. Use explicit size comparisons if we're not interested in the
WORDSIZE, anyway.
(David: adjust commit message to explain why we do this)
The alloca_align() helper is the alloca() equivalent of posix_memalign().
As there is no such function provided by glibc, we simply account for
additional memory and return a pointer offset into the allocated memory to
grant the alignment.
Furthermore, alloca0_align() is added, which simply clears the allocated
memory.
If we invoke agents, we should make sure we actually can kill them
again. I mean, it's probably not our job to cleanup the signals if our
tools are invoked in weird contexts, but at least we should make sure,
that the subprocesses we invoke and intend to control work as intended.
Also see:
http://lists.freedesktop.org/archives/systemd-devel/2014-August/022460.html
When this system-wide start-up timeout is hit we execute one of the
failure actions already implemented for services that fail.
This should not only be useful on embedded devices, but also on laptops
which have the power-button reachable when the lid is closed. This
devices, when in a backpack might get powered on by accident due to the
easily reachable power button. We want to make sure that the system
turns itself off if it starts up due this after a while.
When the system manages to fully start-up logind will suspend the
machine by default if the lid is closed. However, in some cases we don't
even get as far as logind, and the boot hangs much earlier, for example
because we ask for a LUKS password that nobody ever enters.
Yeah, this is a real-life problem on my Yoga 13, which has one of those
easily accessible power buttons, even if the device is closed.
This way we can use it on non-const strings, and don't end up with a
const'ified result.
This is similar to libc's strstr() which also takes a const string but
returns a non-const one.
This breaks udev-builtin-btrfs.c, which reinvents some of missing.h,
so use missing.h there too.
[zj: removed #include "config.h" and wrapped #include <linux/btrfs.h>
in ifdef HAVE_LINUX_BTRFS_H as discussed on the mailing list.]
String which ended in an unfinished quote were accepted, potentially
with bad memory accesses.
Reject anything which ends in a unfished quote, or contains
non-whitespace characters right after the closing quote.
_FOREACH_WORD now returns the invalid character in *state. But this return
value is not checked anywhere yet.
Also, make 'word' and 'state' variables const pointers, and rename 'w'
to 'word' in various places. Things are easier to read if the same name
is used consistently.
mbiebl_> am I correct that something like this doesn't work
mbiebl_> ExecStart=/usr/bin/encfs --extpass='/bin/systemd-ask-passwd "Unlock EncFS"'
mbiebl_> systemd seems to strip of the quotes
mbiebl_> systemctl status shows
mbiebl_> ExecStart=/usr/bin/encfs --extpass='/bin/systemd-ask-password Unlock EncFS $RootDir $MountPoint
mbiebl_> which is pretty weird
Turns out, making strings shell-proof is harder than expected:
# machinectl set-hostname "foo|poweroff" && . /etc/machine-info
(This could be simplified by quoting *and* escaping all characters,
which is harmless in shell but unnecessary.)
As Zbigniew pointed out a new ConditionFirstBoot= appears like the nicer
way to hook in systemd-firstboot.service on first boots (those with /etc
unpopulated), so let's do this, and get rid of the generator again.
A new tool "systemd-firstboot" can be used either interactively on boot,
where it will query basic locale, timezone, hostname, root password
information and set it. Or it can be used non-interactively from the
command line when prepareing disk images for booting. When used
non-inertactively the tool can either copy settings from the host, or
take settings on the command line.
$ systemd-firstboot --root=/path/to/my/new/root --copy-locale --copy-root-password --hostname=waldi
The tool will be automatically invoked (interactively) now on first boot
if /etc is found unpopulated.
This also creates the infrastructure for generators to be notified via
an environment variable whether they are running on the first boot, or
not.
systemctl -H root@foobar:waldi
will now show a list of services running on container "waldi" on host
"foobar", using "root" for authenticating at "foobar".
Since entereing a container requires priviliges, this will only work
correctly for root logins.
Passing 0 to malloc() is not required to return NULL. Therefore, don't
bail out if "b" is 0. This is not of importance to the existing helpers,
but the upcoming realloc_multiply() requires this. To keep consistence, we
keep the same behavior for the other helpers.
systemd-sysusers is a tool to reconstruct /etc/passwd and /etc/group
from static definition files that take a lot of inspiration from
tmpfiles snippets. These snippets should carry information about system
users only. To make sure it is not misused for normal users these
snippets only allow configuring UID and gecos field for each user, but
do not allow configuration of the home directory or shell, which is
necessary for real login users.
The purpose of this tool is to enable state-less systems that can
populate /etc with the minimal files necessary, solely from static data
in /usr. systemd-sysuser is additive only, and will never override
existing users.
This tool will create these files directly, and not via some user
database abtsraction layer. This is appropriate as this tool is supposed
to run really early at boot, and is only useful for creating system
users, and system users cannot be stored in remote databases anyway.
The tool is also useful to be invoked from RPM scriptlets, instead of
useradd. This allows moving from imperative user descriptions in RPM to
declarative descriptions.
The UID/GID for a user/group to be created can either be chosen dynamic,
or fixed, or be read from the owner of a file in the file system, in
order to support reconstructing the correct IDs for files that shall be
owned by them.
This also adds a minimal user definition file, that should be
sufficient for most basic systems. Distributions are expected to patch
these files and augment the contents, for example with fixed UIDs for
the users where that's necessary.
Instead of blindly creating another bind mount for read-only mounts,
check if there's already one we can use, and if so, use it. Also,
recursively mark all submounts read-only too. Also, ignore autofs mounts
when remounting read-only unless they are already triggered.
Let's unify generation of unicode chars at one place.
Also, don't add an extra space into chars we print, except for the tree
chars where this is really necessary.
Lennart Poettering
Jakub Filak
Tom Gundersen
David Herrmann
Michal Schmidt
Michal Sekletar
Emil Renner Berthing
Zbigniew Jędrzejewski-Szmek
Timofey Titovets
Dave Reisner
Simon McVittie
Mantas Mikulėnas
Kay Sievers