Users are often surprised that "systemd-run" command lines like
"systemd-run -p User=idontexist /bin/true" will return successfully,
even though the logs show that the process couldn't be invoked, as the
user "idontexist" doesn't exist. This is because Type=simple will only
wait until fork() succeeded before returning start-up success.
This patch adds a new service type Type=exec, which is very similar to
Type=simple, but waits until the child process completed the execve()
before returning success. It uses a pipe that has O_CLOEXEC set for this
logic, so that the kernel automatically sends POLLHUP on it when the
execve() succeeded but leaves the pipe open if not. This means PID 1
waits exactly until the execve() succeeded in the child, and not longer
and not shorter, which is the desired functionality.
Making use of this new functionality, the command line
"systemd-run -p User=idontexist -p Type=exec /bin/true" will now fail,
as expected.
When process fd lists to pass to activated programs we always place the
socket activation fds first, and the storage fds last. Irritatingly in
almost all calls the "n_storage_fds" parameter (i.e. the number of
storage fds to pass) came first so far, and the "n_socket_fds" parameter
second. Let's clean this up, and specify the number of fds in the order
the fds themselves are passed.
(Also, let's fix one more case where "unsigned" was used to size an
array, while we should use "size_t" instead.)
machined exposes the pseudo-container ".host" as a reference to the host
system, and this means "machinectl login .host" and "machinectl shell
.host" get your a login/shell on the host. systemd-run currently doesn't
allow that. Let's fix that, and make sd-bus understand ".host" as an
alias for connecting to the host system.
1. Document the new desktop= parameter
2. Clarify that we set XDG_SESSION_DESKTOP, XDG_SESSION_CLASS,
XDG_SESSION_TYPE if we have the data, and don't just read it.
We likely get the data from the env block, but we might also determine
it from elsewhere (such as PAM module parameters). Let's set the env
vars on the env block explicitly, so that they are available always, and
apps can rely on it.
Let's make this symmetric with XDG_SESSION_CLASS and XDG_SESSION_TYPE,
so that PAM stacks can configure this easily without involving env vars,
in case there are PAM session managers which only support a single
desktop anyway.
Since D-Bus 1.9.14 (2015-03-02) dbus looks in $XDG_RUNTIME_DIR/bus for
the system bus on its own, hence we can finally drop setting this
environment variable. gdbus since glib 2.45.3 (June 2015) also supports
it.
When networkd has not connected and setting hostname/timezone is
requested, the operation is delayed, not canceled. So, logging in
debug level is sufficient for the corresponding log message.
Closes#9699.
Add CC0 as the license. SPDX does not have a "public domain" tag, but CC0 is
more or less equivalent. We should have *some* header to avoid doubts in the
future.
After upgrading to emacs-26.1-1.fc28.x86_64 I noticed that our
.dir-locals.el files weren't honoured anymore (specifically the fill
column variable is not correctly set for c-mode files). I finally
tracked this down to the order in which items are listed in
.dir-locals.el: if the "nil" one is listed last everything works,
otherwise, it's the one that is applied instead of the c-mode one.
This patch simply swaps the entries, and puts the "nil" one last. My
emacs lisp fu is a bit too limited to understand the full impact for
this, and why emacs 26.1 changed behaviour in this regard, but from an
outsider's view the order shouldn't negatively affect things otherwise,
hence this patch.
