depot/third_party/nixpkgs/nixos/modules/services/x11/display-managers/default.nix

319 lines
12 KiB
Nix

# This module declares the options to define a *display manager*, the
# program responsible for handling X logins (such as LightDM, GDM, or SDDM).
# The display manager allows the user to select a *session
# type*. When the user logs in, the display manager starts the
# *session script* ("xsession" below) to launch the selected session
# type. The session type defines two things: the *desktop manager*
# (e.g., KDE, Gnome or a plain xterm), and optionally the *window
# manager* (e.g. kwin or twm).
{ config, lib, options, pkgs, ... }:
let
inherit (lib) mkOption types literalExpression optionalString;
cfg = config.services.xserver;
xorg = pkgs.xorg;
fontconfig = config.fonts.fontconfig;
xresourcesXft = pkgs.writeText "Xresources-Xft" ''
Xft.antialias: ${if fontconfig.antialias then "1" else "0"}
Xft.rgba: ${fontconfig.subpixel.rgba}
Xft.lcdfilter: lcd${fontconfig.subpixel.lcdfilter}
Xft.hinting: ${if fontconfig.hinting.enable then "1" else "0"}
Xft.autohint: ${if fontconfig.hinting.autohint then "1" else "0"}
Xft.hintstyle: ${fontconfig.hinting.style}
'';
# FIXME: this is an ugly hack.
# Some sessions (read: most WMs) don't activate systemd's `graphical-session.target`.
# Other sessions (read: most non-WMs) expect `graphical-session.target` to be reached
# when the entire session is actually ready. We used to just unconditionally force
# `graphical-session.target` to be activated in the session wrapper so things like
# xdg-autostart-generator work on sessions that are wrong, but this broke sessions
# that do things right. So, preserve this behavior (with some extra steps) by matching
# on XDG_CURRENT_DESKTOP and deliberately ignoring sessions we know can do the right thing.
fakeSession = action: ''
session_is_systemd_aware=$(
IFS=:
for i in $XDG_CURRENT_DESKTOP; do
case $i in
KDE|GNOME|Pantheon|X-NIXOS-SYSTEMD-AWARE) echo "1"; exit; ;;
*) ;;
esac
done
)
if [ -z "$session_is_systemd_aware" ]; then
/run/current-system/systemd/bin/systemctl --user ${action} nixos-fake-graphical-session.target
fi
'';
# file provided by services.xserver.displayManager.sessionData.wrapper
xsessionWrapper = pkgs.writeScript "xsession-wrapper"
''
#! ${pkgs.bash}/bin/bash
# Shared environment setup for graphical sessions.
. /etc/profile
if test -f ~/.profile; then
source ~/.profile
fi
cd "$HOME"
# Allow the user to execute commands at the beginning of the X session.
if test -f ~/.xprofile; then
source ~/.xprofile
fi
${optionalString config.services.displayManager.logToJournal ''
if [ -z "$_DID_SYSTEMD_CAT" ]; then
export _DID_SYSTEMD_CAT=1
exec ${config.systemd.package}/bin/systemd-cat -t xsession "$0" "$@"
fi
''}
${optionalString config.services.displayManager.logToFile ''
exec &> >(tee ~/.xsession-errors)
''}
# Load X defaults. This should probably be safe on wayland too.
${xorg.xrdb}/bin/xrdb -merge ${xresourcesXft}
if test -e ~/.Xresources; then
${xorg.xrdb}/bin/xrdb -merge ~/.Xresources
elif test -e ~/.Xdefaults; then
${xorg.xrdb}/bin/xrdb -merge ~/.Xdefaults
fi
# Import environment variables into the systemd user environment.
${optionalString (cfg.displayManager.importedVariables != []) (
"/run/current-system/systemd/bin/systemctl --user import-environment "
+ toString (lib.unique cfg.displayManager.importedVariables)
)}
# Speed up application start by 50-150ms according to
# https://kdemonkey.blogspot.com/2008/04/magic-trick.html
compose_cache="''${XCOMPOSECACHE:-$HOME/.compose-cache}"
mkdir -p "$compose_cache"
# To avoid accidentally deleting a wrongly set up XCOMPOSECACHE directory,
# defensively try to delete cache *files* only, following the file format specified in
# https://gitlab.freedesktop.org/xorg/lib/libx11/-/blob/master/modules/im/ximcp/imLcIm.c#L353-358
# sprintf (*res, "%s/%c%d_%03x_%08x_%08x", dir, _XimGetMyEndian(), XIM_CACHE_VERSION, (unsigned int)sizeof (DefTree), hash, hash2);
${pkgs.findutils}/bin/find "$compose_cache" -maxdepth 1 -regextype posix-extended -regex '.*/[Bl][0-9]+_[0-9a-f]{3}_[0-9a-f]{8}_[0-9a-f]{8}' -delete
unset compose_cache
# Work around KDE errors when a user first logs in and
# .local/share doesn't exist yet.
mkdir -p "''${XDG_DATA_HOME:-$HOME/.local/share}"
unset _DID_SYSTEMD_CAT
${cfg.displayManager.sessionCommands}
${fakeSession "start"}
# Allow the user to setup a custom session type.
if test -x ~/.xsession; then
eval exec ~/.xsession "$@"
fi
if test "$1"; then
# Run the supplied session command. Remove any double quotes with eval.
eval exec "$@"
else
# TODO: Do we need this? Should not the session always exist?
echo "error: unknown session $1" 1>&2
exit 1
fi
'';
in
{
options = {
services.xserver.displayManager = {
xauthBin = mkOption {
internal = true;
default = "${xorg.xauth}/bin/xauth";
defaultText = literalExpression ''"''${pkgs.xorg.xauth}/bin/xauth"'';
description = "Path to the {command}`xauth` program used by display managers.";
};
xserverBin = mkOption {
type = types.path;
description = "Path to the X server used by display managers.";
};
xserverArgs = mkOption {
type = types.listOf types.str;
default = [];
example = [ "-ac" "-logverbose" "-verbose" "-nolisten tcp" ];
description = "List of arguments for the X server.";
};
setupCommands = mkOption {
type = types.lines;
default = "";
description = ''
Shell commands executed just after the X server has started.
This option is only effective for display managers for which this feature
is supported; currently these are LightDM, GDM and SDDM.
'';
};
sessionCommands = mkOption {
type = types.lines;
default = "";
example =
''
xmessage "Hello World!" &
'';
description = ''
Shell commands executed just before the window or desktop manager is
started. These commands are not currently sourced for Wayland sessions.
'';
};
session = mkOption {
default = [];
type = types.listOf types.attrs;
example = literalExpression
''
[ { manage = "desktop";
name = "xterm";
start = '''
''${pkgs.xterm}/bin/xterm -ls &
waitPID=$!
''';
}
]
'';
description = ''
List of sessions supported with the command used to start each
session. Each session script can set the
{var}`waitPID` shell variable to make this script
wait until the end of the user session. Each script is used
to define either a window manager or a desktop manager. These
can be differentiated by setting the attribute
{var}`manage` either to `"window"`
or `"desktop"`.
The list of desktop manager and window manager should appear
inside the display manager with the desktop manager name
followed by the window manager name.
'';
};
importedVariables = mkOption {
type = types.listOf (types.strMatching "[a-zA-Z_][a-zA-Z0-9_]*");
visible = false;
description = ''
Environment variables to import into the systemd user environment.
'';
};
};
};
config = {
services.displayManager.sessionData.wrapper = xsessionWrapper;
services.xserver.displayManager.xserverBin = "${xorg.xorgserver.out}/bin/X";
services.xserver.displayManager.importedVariables = [
# This is required by user units using the session bus.
"DBUS_SESSION_BUS_ADDRESS"
# These are needed by the ssh-agent unit.
"DISPLAY"
"XAUTHORITY"
# This is required to specify session within user units (e.g. loginctl lock-session).
"XDG_SESSION_ID"
];
systemd.user.targets.nixos-fake-graphical-session = {
unitConfig = {
Description = "Fake graphical-session target for non-systemd-aware sessions";
BindsTo = "graphical-session.target";
};
};
# Create desktop files and scripts for starting sessions for WMs/DMs
# that do not have upstream session files (those defined using services.{display,desktop,window}Manager.session options).
services.displayManager.sessionPackages =
let
dms = lib.filter (s: s.manage == "desktop") cfg.displayManager.session;
wms = lib.filter (s: s.manage == "window") cfg.displayManager.session;
# Script responsible for starting the window manager and the desktop manager.
xsession = dm: wm: pkgs.writeScript "xsession" ''
#! ${pkgs.bash}/bin/bash
# Legacy session script used to construct .desktop files from
# `services.xserver.displayManager.session` entries. Called from
# `sessionWrapper`.
# Start the window manager.
${wm.start}
# Start the desktop manager.
${dm.start}
${optionalString cfg.updateDbusEnvironment ''
${lib.getBin pkgs.dbus}/bin/dbus-update-activation-environment --systemd --all
''}
test -n "$waitPID" && wait "$waitPID"
${fakeSession "stop"}
exit 0
'';
in
# We will generate every possible pair of WM and DM.
lib.concatLists (
lib.mapCartesianProduct
({dm, wm}: let
sessionName = "${dm.name}${optionalString (wm.name != "none") ("+" + wm.name)}";
script = xsession dm wm;
desktopNames = if dm ? desktopNames
then lib.concatStringsSep ";" dm.desktopNames
else sessionName;
in
lib.optional (dm.name != "none" || wm.name != "none")
(pkgs.writeTextFile {
name = "${sessionName}-xsession";
destination = "/share/xsessions/${sessionName}.desktop";
# Desktop Entry Specification:
# - https://standards.freedesktop.org/desktop-entry-spec/latest/
# - https://standards.freedesktop.org/desktop-entry-spec/latest/ar01s06.html
text = ''
[Desktop Entry]
Version=1.0
Type=XSession
TryExec=${script}
Exec=${script}
Name=${sessionName}
DesktopNames=${desktopNames}
'';
} // {
providedSessions = [ sessionName ];
})
)
{ dm = dms; wm = wms; }
);
};
imports = [
(lib.mkRemovedOptionModule [ "services" "xserver" "displayManager" "desktopManagerHandlesLidAndPower" ]
"The option is no longer necessary because all display managers have already delegated lid management to systemd.")
(lib.mkRenamedOptionModule [ "services" "xserver" "displayManager" "job" "logsXsession" ] [ "services" "displayManager" "logToFile" ])
(lib.mkRenamedOptionModule [ "services" "xserver" "displayManager" "logToJournal" ] [ "services" "displayManager" "logToJournal" ])
(lib.mkRenamedOptionModule [ "services" "xserver" "displayManager" "extraSessionFilesPackages" ] [ "services" "displayManager" "sessionPackages" ])
];
}