systemd: allow AF_NETLINK when upnp is enabled

[abouvier]

AF_NETLINK is also needed for the upnp database plugin: https://bbs.archlinux.org/viewtopic.php?id=310134

[MaxKellermann]

Bad commit message

[abouvier]

Where is the guideline for good commit message? :p

[MaxKellermann]

Rule of thumb: if the PR contains text that is missing in your commit message, then your commit message must be obviously bad.

Second rule of thumb: if your commit message describes only what is obvious enough by looking at the diff, but doesn't even try to explain why, it's bad.

[MaxKellermann]

Your commit message says "when upnp is enabled" but that's not what your actual code does - it checks whether the feature is not disabled. That's different from the existing smbclient check, and that has a bad smell. That needs to be explained.

[abouvier]

Because the smbclient option is a boolean, but the upnp option is a combo with multiple ways to be enabled, so checking if it's not disabled is simpler.

[MaxKellermann]

Because the smbclient option is a boolean,

This is wrong. It's a feature.

[MaxKellermann]

Explanation still missing.

[abouvier]

get_option('upnp').enabled() is not possible because this option is not a feature but a combo, so the value returned by get_option will be a string.

Besides, multiple values of this option can end up enabling the upnp plugin, with the logic to determine that in src/lib/upnp/meson.build. So I guess that the best way to verify for sure that upnp is enabled is to check the configuration variable set in this file.