nixpkgs/nixos/modules/services/x11/desktop-managers/default.nix
Tor Hedin Brønner efa27d33cf
nixos/desktopManager: Only trace if the default session isn't found
The default session might be found in `extraSessionFilePackages`, but it's not
viable to detect at evaluation time, so emit a warning.

In LightDM instead of checking `defaultSessionName` against
`displayManager.session.names` we rely on the assertions in
`desktopManager` and `windowMananger` and just check that there's at least one
default set. The second assertion could never actually be triggered.
2018-08-01 19:14:32 +02:00

113 lines
4.3 KiB
Nix

{ config, lib, pkgs, ... }:
with lib;
let
xcfg = config.services.xserver;
cfg = xcfg.desktopManager;
# If desktop manager `d' isn't capable of setting a background and
# the xserver is enabled, `feh' or `xsetroot' are used as a fallback.
needBGCond = d: ! (d ? bgSupport && d.bgSupport) && xcfg.enable;
in
{
# Note: the order in which desktop manager modules are imported here
# determines the default: later modules (if enabled) are preferred.
# E.g., if Plasma 5 is enabled, it supersedes xterm.
imports = [
./none.nix ./xterm.nix ./xfce.nix ./plasma5.nix ./lumina.nix
./lxqt.nix ./enlightenment.nix ./gnome3.nix ./kodi.nix ./maxx.nix
./mate.nix
];
options = {
services.xserver.desktopManager = {
wallpaper = {
mode = mkOption {
type = types.enum [ "center" "fill" "max" "scale" "tile" ];
default = "scale";
example = "fill";
description = ''
The file <filename>~/.background-image</filename> is used as a background image.
This option specifies the placement of this image onto your desktop.
Possible values:
<literal>center</literal>: Center the image on the background. If it is too small, it will be surrounded by a black border.
<literal>fill</literal>: Like <literal>scale</literal>, but preserves aspect ratio by zooming the image until it fits. Either a horizontal or a vertical part of the image will be cut off.
<literal>max</literal>: Like <literal>fill</literal>, but scale the image to the maximum size that fits the screen with black borders on one side.
<literal>scale</literal>: Fit the file into the background without repeating it, cutting off stuff or using borders. But the aspect ratio is not preserved either.
<literal>tile</literal>: Tile (repeat) the image in case it is too small for the screen.
'';
};
combineScreens = mkOption {
type = types.bool;
default = false;
description = ''
When set to <literal>true</literal> the wallpaper will stretch across all screens.
When set to <literal>false</literal> the wallpaper is duplicated to all screens.
'';
};
};
session = mkOption {
internal = true;
default = [];
example = singleton
{ name = "kde";
bgSupport = true;
start = "...";
};
description = ''
Internal option used to add some common line to desktop manager
scripts before forwarding the value to the
<varname>displayManager</varname>.
'';
apply = list: {
list = map (d: d // {
manage = "desktop";
start = d.start
+ optionalString (needBGCond d) ''
if [ -e $HOME/.background-image ]; then
${pkgs.feh}/bin/feh --bg-${cfg.wallpaper.mode} ${optionalString cfg.wallpaper.combineScreens "--no-xinerama"} $HOME/.background-image
else
# Use a solid black background as fallback
${pkgs.xorg.xsetroot}/bin/xsetroot -solid black
fi
'';
}) list;
needBGPackages = [] != filter needBGCond list;
};
};
default = mkOption {
type = types.str;
default = "";
example = "none";
description = "Default desktop manager loaded if none have been chosen.";
apply = defaultDM:
if defaultDM == "" && cfg.session.list != [] then
(head cfg.session.list).name
else if any (w: w.name == defaultDM) cfg.session.list then
defaultDM
else
builtins.trace ''
Default desktop manager (${defaultDM}) not found at evaluation time.
These are the known valid session names:
${concatMapStringsSep "\n " (w: "services.xserver.desktopManager.default = \"${w.name}\";") cfg.session.list}
It's also possible the default can be found in one of these packages:
${concatMapStringsSep "\n " (p: p.name) config.services.xserver.displayManager.extraSessionFilePackages}
'' defaultDM;
};
};
};
config.services.xserver.displayManager.session = cfg.session.list;
}