$ find * -type f |xargs perl contrib/scripts/spdx.pl
  $ git rm contrib/scripts/spdx.pl

Only happens with debug logging enabled. So, not a large problem.

Found by Coverity.

Fixes: d9a4b59c18e3 ('acd: adapt NM code and build options')

We no longer add these. If you use Emacs, configure it yourself.

Also, due to our "smart-tab" usage the editor anyway does a subpar
job handling our tabs. However, on the upside every user can choose
whatever tab-width he/she prefers. If "smart-tabs" are used properly
(like we do), every tab-width will work.

No manual changes, just ran commands:

    F=($(git grep -l -e '-\*-'))
    sed '1 { /\/\* *-\*-  *[mM]ode.*\*\/$/d }'     -i "${F[@]}"
    sed '1,4 { /^\(#\|--\|dnl\) *-\*- [mM]ode/d }' -i "${F[@]}"

Check remaining lines with:

    git grep -e '-\*-'

The ultimate purpose of this is to cleanup our files and eventually use
SPDX license identifiers. For that, first get rid of the boilerplate lines.

... and nm_acd_manager_announce_addresses().

The test will need more information to know why it may fail.
Return a NetworkManager error code, instead of a boolean.

NM_UTILS_LOOKUP_STR() uses alloca(). Partly to avoid the overhead of
malloc(), but more important because it's convenient to use. It does
not require to declare a varible to manage the lifetime of the heap
allocation.

It's quite safe, because the stack allocation is of a fixed size of only
a few bytes. Overall, I think the convenience that we get (resulting in
simpler code) outweighs the danger of stack allocation in this case. It's
still worth it.
However, as it uses alloca(), it still must not be used inside a (unbound)
loop and it is obviously a macro.

Rename the macros to have a _A() suffix. This should make the
peculiarities more apparent.

While nm_utils_inet*_ntop() accepts a %NULL buffer to fallback
to a static buffer, don't do that.

I find the possibility of using a static buffer here error prone
and something that should be avoided. There is of course the downside,
that in some cases it requires an additional line of code to allocate
the buffer on the stack as auto-variable.

Since commit 945c904f956 "platform: assert against valid ifindex and
remove duplicate assertions", it is no longer allowed to call certain
platform functions with invalid ifindex.

These trigger now an assertion. Note that the assertion is merely a
g_return_val_if_fail(), hence in non-debug mode, this does not lead to
a crash.

Fixes: 945c904f956580616f0d71b13c63f525c184060c

NMAcdManager is a rather simple instance.

It does not need (thread-safe) ref-counting, in fact, having
it ref-counted makes it slighly ugly that we connect a signal,
but never bother to disconnect it (while the ref-counted instance
could outlife the signal subscriber).

We also don't need GObject signals. They have more overhead
and are less type-safe than a regular function pointers. Signals
would make sense, if there could be multiple independent listeners,
but that just doesn't make sense.

Implementing it as a plain struct is less lines of code, and less
runtime over head.

Also drop the possiblitiy to reset the NMAcdManager instance.
It wasn't needed and I think it was buggy because it wouldn't
reset the n-acd instance.

https://github.com/NetworkManager/NetworkManager/pull/213

Don't emit signals while popping acd events. Otherwise, we can get
a crash:

    #0  0x000055c2bb094e3b in n_acd_pop_event (acd=0x0, eventp=eventp@entry=0x7ffd47de65b0) at shared/n-acd/src/n-acd.c:846
            node = <optimized out>
            t_node = <optimized out>
    #1  0x000055c2baff53be in acd_event (source=<optimized out>, condition=<optimized out>, data=0x55c2bc4a6cf0) at src/devices/nm-acd-manager.c:180
            self = 0x55c2bc4a6cf0
            priv = 0x55c2bc4a6d08
            __func__ = "acd_event"
            event = 0x55c2bc593af0
            info = 0x55c2bc4b76c0
            address_str = "\000\000\000\000\000\000\000\000\bd\373\272\302U\000"
            hwaddr_str = 0x0
            r = <optimized out>
    #2  0x00007eff336238f9 in g_main_context_dispatch (context=0x55c2bc41f480) at gmain.c:3146
            dispatch = 0x7eff336688a0 <g_io_unix_dispatch>
            prev_source = 0x0
            was_in_call = 0
            user_data = 0x55c2bc4a6cf0
            callback = 0x55c2baff5310 <acd_event>
            cb_funcs = 0x7eff338eb920 <g_source_callback_funcs>
            cb_data = 0x55c2bc558680
            need_destroy = <optimized out>
            source = 0x55c2bc58c160
            current = 0x55c2bc43dd10
            i = 0
    ...

While at it, don't return from the events N_ACD_EVENT_DEFENDED,
N_ACD_EVENT_CONFLICT, and <default>, but continue popping events.

Fixes: d9a4b59c18e36f2b577744b7fe6710d71161ca12