services/turnstiled: init

[xZecora]

initial commit for the turnstiled service. currently very barebones

[aanderse]

awesome! please hold off merging for a few days, i would like to share some related dinit work i have been doing so we can potentially integrate

[aanderse]

very cool! this will work so well with the dinit.services and dinit.user.services options i have written!

[xZecora]

I implemented basically all of your changes alongside my corrections, @aanderse. The dinit backend works fine on my machine as basically a drop in replacement.

Implemented the usr/turnstiled-start trigger for tty services and a prescript for turnstiled to trigger it, making sure the user, more than likely, can't log in without turnstile starting first, though there is a chance if they have autologin potentially. I haven't tested this with autologin but that might be something to consider. Also worth thinking about if we want to pivot to the recovery mode if it fails instead of just failing silently like we discussed. We could also make this a toggle if we want to.

The only thing I might like to see added, besides better runit support, would be a prewritten service for managing dbus for the user if they enable the export session address option or a new option we could add, but I'm unsure if that should fall outside the scope of this module. Maybe if we merge this upstream in finix we can add that in an extended module here? I'm happy to share the relatively simple service and task pair I use for this purpose either way.