The following configuration generates a systemd unit that doesn't
start.
```nix
{
services.syncthing = {
enable = true;
user = "my-user";
};
}
```
It fails with
```
systemd[1]: Started Syncthing service.
systemd[6745]: syncthing.service: Failed to determine group credentials: No such process
systemd[6745]: syncthing.service: Failed at step GROUP spawning /nix/store/n1ydz3i08nqp1ajc50ycy1zribmphqc9-syncthing-1.1.4-bin/bin/syncthing: No such process
systemd[1]: syncthing.service: Main process exited, code=exited, status=216/GROUP
systemd[1]: syncthing.service: Failed with result 'exit-code'.
```
This is due to the fact that `syncthing` group (default) is not
created if the user is overridden.
Add a separate check for setting up the default group, so that
user/group are created independently.
This is a refactor of how resolvconf is managed on NixOS. We split it
into a separate service which is enabled internally depending on whether
we want /etc/resolv.conf to be managed by it. Various services now take
advantage of those configuration options.
We also now use systemd instead of activation scripts to update
resolv.conf.
NetworkManager now uses the right option for rc-manager DNS
automatically, so the configuration option shouldn't be exposed.
We were already creating a group for the user under which to run syncthing but
we were defaulting to running as `nogroup`.
Additionally, use `install` instead of multiple calls to mkdir/cp/chown.
Add an option to set the rc-manager parameter in NetworkManager.conf,
which controls how NetworkManager handles resolv.conf. This sets the
default rc-manager to "resolvconf", which solves #61490. It
additionally allows the user to change rc-manager without interference
from configuration activations.
Applies OpenWRT's noscan patch to hostapd and the relevant option to
the hostapd module.
This noscan patch adds a new `noscan` option allowing us to create
some overlapping BSSs in HT40+/- mode.
Note: this option is disabled by default, we leave this up to the end
user whether it should be enabled or not.
Not being able to create those overlapping BSSs is basically
preventing us to use 802.11n in any urban area where chances to
overlap with another SSID are extremely high.
The patch we are using is a courtesy of the openwrt team and is
applied to the defaul hostapd package in both OpenWRT and Archlinux.
