refactor: s6/unl0kr/profile: put more shell init stuff directly in modules/users/default.nix when it doesnt benefit from being pluggable

hosts/common/programs/sway/default.nix

@@ -14,18 +14,6 @@ let
       test -e /tmp/.X11-unix || \
         echo "warning: required directory not found (create it?): /tmp/.X11-unix"
 
-      # sway needs to know which virtual TTY to render to
-      setVtnr() {
-        local ttyPath="$(tty)"
-        case $ttyPath in
-          (/dev/tty*)
-            export XDG_VTNR=''${ttyPath#/dev/tty}
-            ;;
-        esac
-      }
-      if ! [ -v "$XDG_VTNR" ]; then
-        setVtnr
-      fi
       # delete DISPLAY-related vars from env before launch, else sway will try to connect to a remote display.
       # (consider: nested sway sessions, where sway actually has a reason to read these)
       exec env -u DISPLAY -u WAYLAND_DISPLAY "DESIRED_WAYLAND_DISPLAY=$WAYLAND_DISPLAY" ${configuredSway}/bin/sway 2>&1

hosts/common/programs/unl0kr/default.nix

@@ -1,8 +1,6 @@
 { config, lib, pkgs, ... }:
 let
   cfg = config.sane.programs.unl0kr;
-
-  tty = "tty${builtins.toString cfg.config.vt}";
 in
 {
   sane.programs.unl0kr = {
@@ -18,33 +16,8 @@ in
             and allowing password auth via either keyboard, mouse, or touch.
           '';
         };
-        options.vt = mkOption {
-          type = types.int;
-          default = 1;
-        };
-        options.delay = mkOption {
-          type = types.int;
-          default = 3;
-          description = ''
-            seconds to wait between successful login and running the `afterLogin` command.
-            this is a safety mechanism, to allow users an exit in case DE is broken.
-          '';
       };
     };
-    };
-
-    # TODO: lift this into toplevel s6 stuff
-    fs.".profile".symlink.text = ''
-      unl0krCheck() {
-        # if already running a desktop environment, or if running from ssh, then `tty` will show /dev/pts/NN.
-        # if the `sleep` call is `Ctrl+C'd`, then it'll exit false and the session commands won't be launched
-        [ "$(tty)" = "/dev/${tty}" ] && (( ''${#primarySessionCommands[@]} )) \
-          && echo "launching primary session commands in ${builtins.toString cfg.config.delay}s: ''${primarySessionCommands[*]}" \
-          && sleep ${builtins.toString cfg.config.delay}
-      }
-      primarySessionChecks+=('unl0krCheck')
-
-    '';
 
     # N.B.: this sandboxing applies to `unl0kr` itself -- the on-screen-keyboard;
     #       NOT to the wrapper which invokes `login`.
@@ -64,7 +37,7 @@ in
 
     services.unl0kr = {
       description = "unl0kr framebuffer password entry/filesystem unlocker";
-      partOf = [ "private-storage" ];
+      partOf = lib.mkIf cfg.config.autostart [ "private-storage" ];
       command = pkgs.writeShellScript "unl0kr-start" ''
         while ! test -f /mnt/persist/private/init; do
           if test -f /run/gocryptfs/private.key; then
@@ -73,10 +46,12 @@ in
             ${lib.getExe' pkgs.inotify-tools "inotifywait"} --timeout 4 --event create --event delete /mnt/persist/private /run/gocryptfs
           else
             echo "starting unl0kr"
+            if [ -n "$XDG_VTNR" ]; then
               # switch back to the tty our session is running on (in case the user tabbed away after logging in),
               # as only that TTY is sure to have echo disabled.
               # this is racy, but when we race it's obvious from the UI that your password is being echo'd
-            ${lib.getExe' pkgs.kbd "chvt"} ${builtins.toString cfg.config.vt}
+              ${lib.getExe' pkgs.kbd "chvt"} "$XDG_VTNR"
+            fi
             unl0kr > /run/gocryptfs/private.key.incoming &&
               cp /run/gocryptfs/private.key.incoming /run/gocryptfs/private.key
             echo "unl0kr exited"

modules/users/default.nix

@@ -241,14 +241,34 @@ let
               runCommands "''${sessionCommands[@]}"
             }
             maybeInitPrimarySession() {
-              for c in "''${primarySessionChecks[@]}"; do
+              local delay=3
-                if eval "$c"; then
+              if test "$XDG_VTNR" -eq 1 \
+                && (( ''${#primarySessionCommands[@]} )) \
+                && echo "launching primary session commands in ''${delay}s: ''${primarySessionCommands[*]}" \
+                && sleep $delay \
+              ; then
                 runCommands "''${primarySessionCommands[@]}"
-                  return
               fi
-              done
             }
 
+            setVTNR() {
+              # some desktops (e.g. sway) need to know which virtual TTY to render to.
+              # it's also nice, to guess if a user logging into the "default" tty, or
+              # an auxiliary one
+
+              local ttyPath=$(tty)
+              case $ttyPath in
+                (/dev/tty*)
+                  export XDG_VTNR=''${ttyPath#/dev/tty}
+                  ;;
+                (*)
+                  # for terminals running inside a compositor, we do want to explicitly clear XDG_VTNR.
+                  # otherwise, sway will be launched from tty1, then the user will launch a terminal emulator inside sway, but the application will think it's running directly on tty1 (which it isn't)
+                  unset XDG_VTNR
+                  ;;
+              esac
+            }
+            sessionCommands+=('setVTNR')
             # this is *probably not necessary*.
             # historically, Komikku needed to know if it was running under X or Wayland, and used XDG_SESSION_TYPE for that.
             # but unless this is a super common idiom, managing it here is just ugly.