Fix admin unix sockets

[thatsmydoing]

The admin_ws_unix and admin_wss_unix options were mistakenly being taken from the general section instead of the adminsection.

Additionally, admin_ws_unix did not actually set the LWS_SERVER_OPTION_UNIX_SOCK so it would not work anyway.

I decided to just factor out the whole websocket server creation so that any further changes here don't need to be repeated for each variation of the server.

[januscla]

Thanks for your contribution, @thatsmydoing! Please make sure you sign our CLA, as it's a required step before we can merge this.

[lminiero]

Thanks for spotting the issue! I think the refactoring you did is quite helpful, even though from a quick glance it will need fixing (see below).

[lminiero]

I don't think that's correct. With this change, if the config file doesn't have a certs section, but the config file says a secure WebSockets server must be created, the attempt will not fail as it should, but will simply create a plain WebSocket server on the provided port instead, which is wrong.

Depending on the prefix, config_certs may need to be required and not optional.

[thatsmydoing]

Oh, that's right. I initially did have a flag for secure or not but replaced it with just config_certs I forgot that it could be NULL by itself.

[thatsmydoing]

I've fixed the issue and signed the CLA

[lminiero]

Thanks for the quick fixes! I'll do a deeper review and some tests either later today or tomorrow morning, and in case there's no regression, I'll merge 👍

[lminiero]

Looks good, merging ✌️