Coccinelle:

  @@
  expression a, b;
  @@
  -a ? a : b
  +a ?: b

Applied with:

  spatch --sp-file ternary.cocci --in-place --smpl-spacing --dir .

With some manual adjustments on spots that Cocci didn't catch for
reasons unknown.

Thanks to the marvelous effort of the GNU compiler developer we can now
spare a couple of bits that could be used for more important things,
like this commit message. Standards commitees yet have to catch up.

It is meant to be rather similar in nature to isblank() or
g_ascii_isspace().

Sadly, isblank() is locale dependent while g_ascii_isspace() also considers
vertical whitespace as a space. That's no good for configuration files that
are strucutured into lines, which happens to be a pretty common case.

Plugins go to the arch specific place while conf.d/ and VPN/ are in
lib/. Use the same naming as is used with autoconf.

There is no need to perform a lookup by path. NMSettings is a singleton,
it has the connection exactly iff the connection is linked.

Also add an assertion to double-check that the results agree with
the previous implementation.

Normalize coding style by removing consecutive empty lines from C
sources and headers.

https://github.com/NetworkManager/NetworkManager/pull/108

nm_settings_add_connection_dbus() has two callers. One of them is NMManager
during AddAndActivate. In this case, the NMActiveConnection already created
an auth-subject. Re-use it.

Note how creating an auth-subject involves reading procfs to determine
whether the process still exists. This is not about the additional
overhead of that, but about the race where the process could drop
of in the meantime. The calling process might be gone now, and we would
fail creating the auth-subject. There is no need for that, because we
already evaluated all information we need. Quite likely, in the case
of this race, PolicyKit will also determine that the process is gone
and fail authorization too. But that's PolicyKit's decision to make,
not nm_settings_add_connection_dbus()'s.

Fixes: 902bbfdb1878ca54989e7aec6c5d92d1c580e885