Allow SO_REUSEADDR on startup

[Thesola10]

Currently, nixseparatedebuginfod fails when started through systemd's socket activation system, because the address was not released for long enough for a normal bind to work.

There are advantages to using socket activation for nixseparatedebuginfod, namely to avoid the indexing process until debug info is actually needed. Would it be possible to provide a configuration option that allows SO_REUSEADDR for use with socket activation?

[symphorien]

Hi

• I don't think nixseparatedebuginfo is a good fit for socket activation. See previous discussions here Support systemd socket activation #10 I'll add that the debuginfo client from elfutils really likes to cache failures so blocking full minutes until results are available is problematic.
• I think that to properly implement socket activation you have to inherit the socket via sd_listen_fds(3). From a cursory look, SO_REUSE_ADDR looks like a workaround.

For these reasons I don't plan work in this direction. If I wanted to dedicate time to reduce the power consumption of nixseparatedebuginfod I'd rather implement watching the nix sqlitedb with inotify, or even remove the need for indexation nixpkgs side.