sed 's#^/\*\{5\}\*\+/$#/*****************************************************************************/#' $(git grep -l '\*\{5\}' | grep '\.[hc]$') -i

A large part of "nm-test-utils.h" is only relevant for tests inside "src/"
directory, as they are helpers related to NetworkManager core part.

Split this part out of "nm-test-utils.h" header.

- All internal source files (except "examples", which are not internal)
  should include "config.h" first. As also all internal source
  files should include "nm-default.h", let "config.h" be included
  by "nm-default.h" and include "nm-default.h" as first in every
  source file.
  We already wanted to include "nm-default.h" before other headers
  because it might contains some fixes (like "nm-glib.h" compatibility)
  that is required first.

- After including "nm-default.h", we optinally allow for including the
  corresponding header file for the source file at hand. The idea
  is to ensure that each header file is self contained.

- Don't include "config.h" or "nm-default.h" in any header file
  (except "nm-sd-adapt.h"). Public headers anyway must not include
  these headers, and internal headers are never included after
  "nm-default.h", as of the first previous point.

- Include all internal headers with quotes instead of angle brackets.
  In practice it doesn't matter, because in our public headers we must
  include other headers with angle brackets. As we use our public
  headers also to compile our interal source files, effectively the
  result must be the same. Still do it for consistency.

- Except for <config.h> itself. Include it with angle brackets as suggested by
  https://www.gnu.org/software/autoconf/manual/autoconf.html#Configuration-Headers

Rather than randomly including one or more of <glib.h>,
<glib-object.h>, and <gio/gio.h> everywhere (and forgetting to include
"nm-glib-compat.h" most of the time), rename nm-glib-compat.h to
nm-glib.h, include <gio/gio.h> from there, and then change all .c
files in NM to include "nm-glib.h" rather than including the glib
headers directly.

(Public headers files still have to include the real glib headers,
since nm-glib.h isn't installed...)

Also, remove glib includes from header files that are already
including a base object header file (which must itself already include
the glib headers).

config.h should be included from every .c file, and it should be
included before any other include. Fix that.

(As a side effect of how I did this, this also changes us to
consistently use "config.h" rather than <config.h>. To the extent that
it matters [which is not much], quotes are more correct anyway, since
we're talking about a file in our own build tree, not a system
include.)

g_type_init() deprecation:
https://bugzilla.gnome.org/show_bug.cgi?id=686161

Non-git-master versions of lldpad refuse to touch a device that doesn't
have a carrier.  And when enabling/disabling DCB, the kernel driver will
reconfigure itself and may turn carrier off for a few seconds.  So we
must ensure that before enabling/disabling DCB, the carrier is already
on.  Next we must ensure that *after* enabling/disabling DCB, the
carrier is back on before doing further DCB setup.

There's a race condition between enabling/disabling DCB and receiving
the carrier event in NetworkManager that has to be handled carefully.
Because the carrier may not yet be down after the dcbtool call to
enable/disable DCB returns, we need to wait for a couple seconds for
the carrier to go down, and then again for it to come back up.
Otherwise we might see the still-on carrier, proceed with DCB setup,
and the carrier finally goes down halfway through the setup, which
will fail the operations with "DCB not enabled, link down, or DCB
not supported" errors from lldpad.

Late-fixup for review comments and I didn't run 'make check'.  Bad me.