syslogd: unlink() -> unlinkat()

[jfree]

Summary

Save basename and dirname for use in unlinkat() when removing UNIX
sockets from fs.

[markj]

Can you use our funlinkat() instead of keeping track of the directory descriptor?

[jfree]

In D41379#942527, @markj wrote:

Can you use our funlinkat() instead of keeping track of the directory descriptor?

Yes. not sure how I missed that.

[jfree]

In D41379#943056, @jfree wrote:

In D41379#942527, @markj wrote:

Can you use our funlinkat() instead of keeping track of the directory descriptor?

Yes. not sure how I missed that.

Actually, after reading about this, I don't think so. It seems like funlinkat() purely exists to ensure that you're unlinking an inode that matches the given path. I don't think it can remove a file without the directory descriptor.

[jfree]

Update after rebase

[markj]

usr.sbin/syslogd/syslogd.c

2352

I'm not convinced we need to do this cleanup (aside from the unlinkat()) immediately prior to exiting. There's a lot of other stuff that isn't cleaned up.

[jfree]

usr.sbin/syslogd/syslogd.c

2352

I'm not convinced we need to do this cleanup (aside from the unlinkat()) immediately prior to exiting. There's a lot of other stuff that isn't cleaned up.

A good portion of this program is inconsistent in this matter. I'll remove it, though.

[jfree]

Remove cleanup in die()

[emaste]

usr.sbin/syslogd/syslogd.c

3792

separate from all of this work I wonder if following the xstrdup pattern makes sense

3796

Are we typically/often going to have more than one AF_LOCAL endpoint open, and would they share a directory? i.e., is it worth trying to cache and share dirfds?