Move slim options into the displayManager attribute set.

Add an enable flag to slim which is by default set to be true.

svn path=/nixos/branches/modular-nixos/; revision=15009

upstart-jobs/xserver/displayManager/slim.nix

@@ -4,9 +4,7 @@
 let
   inherit (pkgs.lib) mkOption;
 
-  options = { services = { xserver = {
+  slimOptions = {
-
-    slim = {
 
     theme = mkOption {
       default = null;
@@ -39,6 +37,32 @@ let
         Hide the mouse cursor on the login screen.
       ";
     };
+
+  };
+
+  options = { services = { xserver = { displayManager = {
+
+    slim = slimOptions // {
+
+      enable = mkOption {
+        default = true;
+        description = "
+          Whether to enable slim as the display manager.
+        ";
+      };
+
+    };
+
+  }; /* displayManager */ }; /* xserver */ }; /* services */ };
+
+  copyOldOptions = { services = { xserver = {
+
+    # Declare old options.
+    slim = slimOptions;
+
+    # Copy the old options into the new options.
+    displayManager = {
+      slim = config.services.xserver.slim;
     };
 
   }; /* xserver */ }; /* services */ };
@@ -49,7 +73,9 @@ in
 let
   xcfg = config.services.xserver;
   dmcfg = xcfg.displayManager;
-  cfg = xcfg.slim;
+  cfg = dmcfg.slim;
+
+  inherit (pkgs.lib) mkIf;
 
   slimConfig = pkgs.writeText "slim.cfg" ''
     xauth_path ${dmcfg.xauthBin}
@@ -80,9 +106,10 @@ let
 
 in
 
-{
+mkIf cfg.enable {
   require = [
     options
+    copyOldOptions
   ];
 
   services = {