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

... and nm_utils_fd_get_contents() and nm_utils_file_set_contents().

Don't mix negative errno return value with a GError output. Instead,
return a boolean result indicating success or failure.

Also, optionally

  - output GError

  - set out_errsv to the positive errno (or 0 on success)

Obviously, the return value and the output arguments (contents, length,
out_errsv, error) must all agree in their success/failure result.
That means, you may check any of the return value, out_errsv, error, and
contents to reliably detect failure or success.

Also note that out_errsv gives the positive(!) errno. But you probably
shouldn't care about the distinction and use nm_errno_native() either
way to normalize the value.

Seen on gitlab-ci.

  NMPlatformSignalAssert: ../src/platform/tests/test-link.c:260, test_slave(): failure to accept signal [0,2] times: link-changed-changed ifindex 15 (3 times received)
  ERROR: src/platform/tests/test-link-linux - too few tests run (expected 76, got 6)
  ERROR: src/platform/tests/test-link-linux - exited with status 133 (terminated by signal 5?)

(cherry picked from commit 483de2bb93ff66afc439f89d3ce8f539acd87867)

IP addresses, routes, TC and QDiscs are all tied to a certain interface.
So when NetworkManager manages an interface, it can be confident that
all related entires should be managed, deleted and modified by NetworkManager.

Routing policy rules are global. For that we have NMPRulesManager which
keeps track of whether NetworkManager owns a rule. This allows multiple
connection profiles to specify the same rule, and NMPRulesManager can
consolidate this information to know whether to add or remove the rule.

NMPRulesManager would also support to explicitly block a rule by
tracking it with negative priority. However that is still unused at
the moment. All that devices do is to add rules (track with positive
priority) and remove them (untrack) once the profile gets deactivated.

As rules are not exclusively owned by NetworkManager, NetworkManager
tries not to interfere with rules that it knows nothing about. That
means in particular, when NetworkManager starts it will "weakly track"
all rules that are present. "weakly track" is mostly interesting for two
cases:

  - when NMPRulesManager had the same rule explicitly tracked (added) by a
    device, then deactivating the device will leave the rule in place.

  - when NMPRulesManager had the same rule explicitly blocked (tracked
    with negative priority), then it would restore the rule when that
    block gets removed (as said, currently nobody actually does this).

Note that when restarting NetworkManager, then the device may stay and
the rules kept. However after restart, NetworkManager no longer knows
that it previously added this route, so it would weakly track it and
never remove them again.

That is a problem. Avoid that, by whenever explicitly tracking a rule we
also make sure to no longer weakly track it. Most likely this rule was
indeed previously managed by NetworkManager. If this was really a rule
added by externally, then the user really should choose distinct
rule priorities to avoid such conflicts altogether.

    nmtst: initialize nmtst_get_rand() with NMTST_SEED_RAND=0
    /link/bogus: OK
    /link/loopback: OK
    /link/internal: OK
    /link/external: OK
    /link/software/bridge: OK
    /link/software/bond: OK
    /link/software/team: NMPlatformSignalAssert: ../src/platform/tests/test-link.c:331, test_slave(): failure to accept signal [0,2] times: 'link-changed-changed' ifindex 15 (3 times received)
    --- stderr ---
    /builds/NetworkManager/NetworkManager/tools/run-nm-test.sh: line 264: 106682 Trace/breakpoint trap      --quiet --error-exitcode= --leak-check=full --gen-suppressions=all  --num-callers=100 --log-file=
    The test failed. Also check the valgrind log at '/builds/NetworkManager/NetworkManager/build/src/platform/tests/test-link-linux.valgrind-log'

  /link/software/bridge: NMPlatformSignalAssert: ../src/platform/tests/test-link.c:289, test_slave(): failure to accept signal [0,2] times: 'link-changed-changed' ifindex 10 (3 times received)

  /link/software/bond: NMPlatformSignalAssert: ../src/platform/tests/test-link.c:243, test_slave(): failure to accept signal [1,2] times: link-changed-changed ifindex 13 (3 times received)

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.

While at it, rename the "addr" field to "l_address". The term "addr" is
used over and over. Instead we should use distinct names that make it
easier to navigate the code.