nixpkgs/nixos/modules/services/x11/display-managers/default.nix
obadz 9be012f0d4 lightdm & xserver service: add ability to spawn more than one X server
- if xserver.tty and/or display are set to null, then don't specify
  them, or the -logfile argument in the xserverArgs
- For lightdm, we set default tty and display to null and we determine
  those at runtime based on arguments passed. This is necessary because
  we run multiple X servers so they can't all be on the same display
2015-12-15 08:49:28 -06:00

330 lines
10 KiB
Nix

# This module declares the options to define a *display manager*, the
# program responsible for handling X logins (such as xdm, kdm, gdb, or
# SLiM). 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, pkgs, ... }:
with lib;
let
cfg = config.services.xserver;
xorg = pkgs.xorg;
vaapiDrivers = pkgs.buildEnv {
name = "vaapi-drivers";
paths = cfg.vaapiDrivers;
# We only want /lib/dri, but with a single input path, we need "/" for it to work
pathsToLink = [ "/" ];
};
fontconfig = config.fonts.fontconfig;
xresourcesXft = pkgs.writeText "Xresources-Xft" ''
${optionalString (fontconfig.dpi != 0) ''Xft.dpi: ${toString fontconfig.dpi}''}
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: ${if fontconfig.hinting.autohint then "1" else "0"}
Xft.hintstyle: hint${fontconfig.hinting.style}
'';
# file provided by services.xserver.displayManager.session.script
xsession = wm: dm: pkgs.writeScript "xsession"
''
#! ${pkgs.bash}/bin/bash
. /etc/profile
cd "$HOME"
# The first argument of this script is the session type.
sessionType="$1"
if [ "$sessionType" = default ]; then sessionType=""; fi
${optionalString (!cfg.displayManager.job.logsXsession) ''
exec > ~/.xsession-errors 2>&1
''}
${optionalString cfg.startDbusSession ''
if test -z "$DBUS_SESSION_BUS_ADDRESS"; then
exec ${pkgs.dbus.tools}/bin/dbus-launch --exit-with-session "$0" "$sessionType"
fi
''}
${optionalString cfg.displayManager.desktopManagerHandlesLidAndPower ''
# Stop systemd from handling the power button and lid switch,
# since presumably the desktop environment will handle these.
if [ -z "$_INHIBITION_LOCK_TAKEN" ]; then
export _INHIBITION_LOCK_TAKEN=1
if ! ${config.systemd.package}/bin/loginctl show-session $XDG_SESSION_ID | grep -q '^RemoteHost='; then
exec ${config.systemd.package}/bin/systemd-inhibit --what=handle-lid-switch:handle-power-key --why="Desktop environment handles power events" "$0" "$sessionType"
fi
fi
''}
${optionalString cfg.startGnuPGAgent ''
if test -z "$SSH_AUTH_SOCK"; then
# Restart this script as a child of the GnuPG agent.
exec "${pkgs.gnupg}/bin/gpg-agent" \
--enable-ssh-support --daemon \
--pinentry-program "${pkgs.pinentry}/bin/pinentry-gtk-2" \
--write-env-file "$HOME/.gpg-agent-info" \
"$0" "$sessionType"
fi
''}
# Handle being called by kdm.
if test "''${1:0:1}" = /; then eval exec "$1"; fi
# Start PulseAudio if enabled.
${optionalString (config.hardware.pulseaudio.enable) ''
${optionalString (!config.hardware.pulseaudio.systemWide)
"${config.hardware.pulseaudio.package}/bin/pulseaudio --start"
}
# Publish access credentials in the root window.
${config.hardware.pulseaudio.package}/bin/pactl load-module module-x11-publish "display=$DISPLAY"
# Keep track of devices. Mostly useful for Phonon/KDE.
${config.hardware.pulseaudio.package}/bin/pactl load-module module-device-manager "do_routing=1"
''}
# Tell systemd about our $DISPLAY. This is needed by the
# ssh-agent unit.
${config.systemd.package}/bin/systemctl --user import-environment DISPLAY
# Load X defaults.
${xorg.xrdb}/bin/xrdb -merge ${xresourcesXft}
if test -e ~/.Xresources; then
${xorg.xrdb}/bin/xrdb -merge ~/.Xresources
elif test -e ~/.Xdefaults; then
${xorg.xrdb}/bin/xrdb -merge ~/.Xdefaults
fi
export LIBVA_DRIVERS_PATH=${vaapiDrivers}/lib/dri
# Speed up application start by 50-150ms according to
# http://kdemonkey.blogspot.nl/2008/04/magic-trick.html
rm -rf $HOME/.compose-cache
mkdir $HOME/.compose-cache
# Work around KDE errors when a user first logs in and
# .local/share doesn't exist yet.
mkdir -p $HOME/.local/share
${cfg.displayManager.sessionCommands}
# Allow the user to execute commands at the beginning of the X session.
if test -f ~/.xprofile; then
source ~/.xprofile
fi
# Allow the user to setup a custom session type.
if test -x ~/.xsession; then
exec ~/.xsession
else
if test "$sessionType" = "custom"; then
sessionType="" # fall-thru if there is no ~/.xsession
fi
fi
# The session type is "<desktop-manager> + <window-manager>", so
# extract those.
windowManager="''${sessionType##* + }"
: ''${windowManager:=${cfg.windowManager.default}}
desktopManager="''${sessionType% + *}"
: ''${desktopManager:=${cfg.desktopManager.default}}
# Start the window manager.
case $windowManager in
${concatMapStrings (s: ''
(${s.name})
${s.start}
;;
'') wm}
(*) echo "$0: Window manager '$windowManager' not found.";;
esac
# Start the desktop manager.
case $desktopManager in
${concatMapStrings (s: ''
(${s.name})
${s.start}
;;
'') dm}
(*) echo "$0: Desktop manager '$desktopManager' not found.";;
esac
test -n "$waitPID" && wait "$waitPID"
exit 0
'';
mkDesktops = names: pkgs.runCommand "desktops"
{ # trivial derivation
preferLocalBuild = true;
allowSubstitutes = false;
}
''
mkdir -p $out
${concatMapStrings (n: ''
cat - > "$out/${n}.desktop" << EODESKTOP
[Desktop Entry]
Version=1.0
Type=XSession
TryExec=${cfg.displayManager.session.script}
Exec=${cfg.displayManager.session.script} '${n}'
X-GDM-BypassXsession=true
Name=${n}
Comment=
EODESKTOP
'') names}
'';
in
{
options = {
services.xserver.displayManager = {
xauthBin = mkOption {
internal = true;
default = "${xorg.xauth}/bin/xauth";
description = "Path to the <command>xauth</command> 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.";
apply = toString;
};
sessionCommands = mkOption {
type = types.lines;
default = "";
example =
''
xmessage "Hello World!" &
'';
description = "Shell commands executed just before the window or desktop manager is started.";
};
hiddenUsers = mkOption {
type = types.listOf types.str;
default = [ "nobody" ];
description = ''
A list of users which will not be shown in the display manager.
'';
};
desktopManagerHandlesLidAndPower = mkOption {
type = types.bool;
default = false;
description = ''
Whether the display manager should prevent systemd from handling
lid and power events. This is normally handled by the desktop
environment's power manager. Turn this off when using a minimal
X11 setup without a full power manager.
'';
};
session = mkOption {
default = [];
example = literalExample
''
[ { 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
<varname>waitPID</varname> shell variable to make this script
wait until the end of the user session. Each script is used
to define either a windows manager or a desktop manager. These
can be differentiated by setting the attribute
<varname>manage</varname> either to <literal>"window"</literal>
or <literal>"desktop"</literal>.
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.
'';
apply = list: rec {
wm = filter (s: s.manage == "window") list;
dm = filter (s: s.manage == "desktop") list;
names = flip concatMap dm
(d: map (w: d.name + optionalString (w.name != "none") (" + " + w.name))
(filter (w: d.name != "none" || w.name != "none") wm));
desktops = mkDesktops names;
script = xsession wm dm;
};
};
job = {
preStart = mkOption {
type = types.lines;
default = "";
example = "rm -f /var/log/my-display-manager.log";
description = "Script executed before the display manager is started.";
};
execCmd = mkOption {
type = types.str;
example = literalExample ''
"''${pkgs.slim}/bin/slim"
'';
description = "Command to start the display manager.";
};
environment = mkOption {
type = types.attrsOf types.unspecified;
default = {};
example = { SLIM_CFGFILE = "/etc/slim.conf"; };
description = "Additional environment variables needed by the display manager.";
};
logsXsession = mkOption {
type = types.bool;
default = false;
description = ''
Whether the display manager redirects the
output of the session script to
<filename>~/.xsession-errors</filename>.
'';
};
};
};
};
config = {
services.xserver.displayManager.xserverBin = "${xorg.xorgserver}/bin/X";
};
}