allow ttrssd to run as a specified user (take two)

[rwv37]

The Tiny Tiny RSS update daemon, ttrssd, from package www/tt-rss, currently runs as user www. This change is meant to enable (optionally) running as a different user, by setting a new flag ttrssd_run_as_user in /etc/rc.conf. For example, to run as the user mmm, add the following line to /etc/rc.conf:

ttrssd_run_as_user="mmm"

If this new flag is not specified, it defaults to running as www (reproducing the behavior from before this change).

I've modified my previous PR for this as suggested by @derekschrock:

[0mp]

Hey! Thanks for the patch!

Have you tried setting ttrssd_user=mmm in rc.conf? This is the canonical way of running a daemon as a specific user.

[derekschrock]

I think I looked at that a while ago but thought it wouldn't work (or work as well) since daemon would be running as non-root and it was easier to to have root own all the logs, pids, etc...

Looking at other things in www that run a service (don't know how I missed them before) but they pre command install /dev/null with permissions/ownership for things like pids. However, that would leave logs to either /var/log to it own dir /var/log/tt-rss/... If so we would need add something to UIDs and/or GIDs? Otherwise continue with the default %%WWWOWN%% (www)?

[rwv37]

@0mp, I believe I did try that -- I think it was the first thing I tried -- but I can't say for sure at the moment, and unfortunately I don't have time to fall back from what I've got working and give it a try. I will try when I get a chance. But in the meantime, I can more confidently say a few things that may be related:

I took a look at my existing /etc/rc.conf/ and saw that I had previously explicitly set up caddy to run as a certain user, via caddy_user. I then looked at /usr/local/etc/rc.d/caddy to check out how it is set and used there, and tried to set up /usr/local/etc/rc.d/ttrssd in a similar way, adding ttrssd_user to it and using that to replace its hardcoded www.

That resulted in some sort of error that, to me, seemed very wacky. Unfortunately, I forget what it was, but in trying to figure it out, I was led to the function rc_run_command (in /etc/rc.subr). In there, I noticed something that seemed to indicate that variables of the form (pkg)_user are somehow treated specially. So, I tried just changing my ttrssd_user to ttrssd_run_as_user, and everything started working just fine.