nixpkgs/nixos/modules/services/x11/display-managers/sddm.nix
Alyssa Ross 7658c90f21
nixos/xserver: improve DM error message when X off
Previously, if you, for example, set
services.xserver.displayManager.sddm.enable, but forgot to set
services.xserver.enable, you would get an error message that looked like
this:

    error: attribute 'display-manager' missing

Which was not particularly helpful.

Using assertions, we can make this message much better.
2019-05-02 16:19:59 +00:00

301 lines
8.5 KiB
Nix

{ config, lib, pkgs, ... }:
with lib;
let
xcfg = config.services.xserver;
dmcfg = xcfg.displayManager;
cfg = dmcfg.sddm;
xEnv = config.systemd.services."display-manager".environment;
inherit (pkgs) sddm;
xserverWrapper = pkgs.writeScript "xserver-wrapper" ''
#!/bin/sh
${concatMapStrings (n: "export ${n}=\"${getAttr n xEnv}\"\n") (attrNames xEnv)}
exec systemd-cat ${dmcfg.xserverBin} ${toString dmcfg.xserverArgs} "$@"
'';
Xsetup = pkgs.writeScript "Xsetup" ''
#!/bin/sh
${cfg.setupScript}
${dmcfg.setupCommands}
'';
Xstop = pkgs.writeScript "Xstop" ''
#!/bin/sh
${cfg.stopScript}
'';
cfgFile = pkgs.writeText "sddm.conf" ''
[General]
HaltCommand=${pkgs.systemd}/bin/systemctl poweroff
RebootCommand=${pkgs.systemd}/bin/systemctl reboot
${optionalString cfg.autoNumlock ''
Numlock=on
''}
[Theme]
Current=${cfg.theme}
ThemeDir=/run/current-system/sw/share/sddm/themes
FacesDir=/run/current-system/sw/share/sddm/faces
[Users]
MaximumUid=${toString config.ids.uids.nixbld}
HideUsers=${concatStringsSep "," dmcfg.hiddenUsers}
HideShells=/run/current-system/sw/bin/nologin
[X11]
MinimumVT=${toString (if xcfg.tty != null then xcfg.tty else 7)}
ServerPath=${xserverWrapper}
XephyrPath=${pkgs.xorg.xorgserver.out}/bin/Xephyr
SessionCommand=${dmcfg.session.wrapper}
SessionDir=${dmcfg.session.desktops}/share/xsessions
XauthPath=${pkgs.xorg.xauth}/bin/xauth
DisplayCommand=${Xsetup}
DisplayStopCommand=${Xstop}
EnableHidpi=${if cfg.enableHidpi then "true" else "false"}
[Wayland]
EnableHidpi=${if cfg.enableHidpi then "true" else "false"}
SessionDir=${dmcfg.session.desktops}/share/wayland-sessions
${optionalString cfg.autoLogin.enable ''
[Autologin]
User=${cfg.autoLogin.user}
Session=${defaultSessionName}.desktop
Relogin=${boolToString cfg.autoLogin.relogin}
''}
${cfg.extraConfig}
'';
defaultSessionName =
let
dm = xcfg.desktopManager.default;
wm = xcfg.windowManager.default;
in dm + optionalString (wm != "none") ("+" + wm);
in
{
options = {
services.xserver.displayManager.sddm = {
enable = mkOption {
type = types.bool;
default = false;
description = ''
Whether to enable sddm as the display manager.
'';
};
enableHidpi = mkOption {
type = types.bool;
default = true;
description = ''
Whether to enable automatic HiDPI mode.
</para>
<para>
Versions up to 0.17 are broken so this only works from 0.18 onwards.
'';
};
extraConfig = mkOption {
type = types.lines;
default = "";
example = ''
[Autologin]
User=john
Session=plasma.desktop
'';
description = ''
Extra lines appended to the configuration of SDDM.
'';
};
theme = mkOption {
type = types.str;
default = "";
description = ''
Greeter theme to use.
'';
};
autoNumlock = mkOption {
type = types.bool;
default = false;
description = ''
Enable numlock at login.
'';
};
setupScript = mkOption {
type = types.str;
default = "";
example = ''
# workaround for using NVIDIA Optimus without Bumblebee
xrandr --setprovideroutputsource modesetting NVIDIA-0
xrandr --auto
'';
description = ''
A script to execute when starting the display server. DEPRECATED, please
use <option>services.xserver.displayManager.setupCommands</option>.
'';
};
stopScript = mkOption {
type = types.str;
default = "";
description = ''
A script to execute when stopping the display server.
'';
};
autoLogin = mkOption {
default = {};
description = ''
Configuration for automatic login.
'';
type = types.submodule {
options = {
enable = mkOption {
type = types.bool;
default = false;
description = ''
Automatically log in as <option>autoLogin.user</option>.
'';
};
user = mkOption {
type = types.nullOr types.str;
default = null;
description = ''
User to be used for the automatic login.
'';
};
relogin = mkOption {
type = types.bool;
default = false;
description = ''
If true automatic login will kick in again on session exit (logout), otherwise it
will only log in automatically when the display-manager is started.
'';
};
};
};
};
};
};
config = mkIf cfg.enable {
assertions = [
{ assertion = xcfg.enable;
message = ''
SDDM requires services.xserver.enable to be true
'';
}
{ assertion = cfg.autoLogin.enable -> cfg.autoLogin.user != null;
message = ''
SDDM auto-login requires services.xserver.displayManager.sddm.autoLogin.user to be set
'';
}
{ assertion = cfg.autoLogin.enable -> elem defaultSessionName dmcfg.session.names;
message = ''
SDDM auto-login requires that services.xserver.desktopManager.default and
services.xserver.windowManager.default are set to valid values. The current
default session: ${defaultSessionName} is not valid.
'';
}
];
services.xserver.displayManager.job = {
environment = {
# Load themes from system environment
QT_PLUGIN_PATH = "/run/current-system/sw/" + pkgs.qt5.qtbase.qtPluginPrefix;
QML2_IMPORT_PATH = "/run/current-system/sw/" + pkgs.qt5.qtbase.qtQmlPrefix;
XDG_DATA_DIRS = "/run/current-system/sw/share";
};
execCmd = "exec /run/current-system/sw/bin/sddm";
};
security.pam.services = {
sddm = {
allowNullPassword = true;
startSession = true;
};
sddm-greeter.text = ''
auth required pam_succeed_if.so audit quiet_success user = sddm
auth optional pam_permit.so
account required pam_succeed_if.so audit quiet_success user = sddm
account sufficient pam_unix.so
password required pam_deny.so
session required pam_succeed_if.so audit quiet_success user = sddm
session required pam_env.so envfile=${config.system.build.pamEnvironment}
session optional ${pkgs.systemd}/lib/security/pam_systemd.so
session optional pam_keyinit.so force revoke
session optional pam_permit.so
'';
sddm-autologin.text = ''
auth requisite pam_nologin.so
auth required pam_succeed_if.so uid >= 1000 quiet
auth required pam_permit.so
account include sddm
password include sddm
session include sddm
'';
};
users.users.sddm = {
createHome = true;
home = "/var/lib/sddm";
group = "sddm";
uid = config.ids.uids.sddm;
};
environment.etc."sddm.conf".source = cfgFile;
environment.pathsToLink = [
"/share/sddm"
];
users.groups.sddm.gid = config.ids.gids.sddm;
environment.systemPackages = [ sddm ];
services.dbus.packages = [ sddm ];
# To enable user switching, allow sddm to allocate TTYs/displays dynamically.
services.xserver.tty = null;
services.xserver.display = null;
systemd.tmpfiles.rules = [
# Prior to Qt 5.9.2, there is a QML cache invalidation bug which sometimes
# strikes new Plasma 5 releases. If the QML cache is not invalidated, SDDM
# will segfault without explanation. We really tore our hair out for awhile
# before finding the bug:
# https://bugreports.qt.io/browse/QTBUG-62302
# We work around the problem by deleting the QML cache before startup.
# This was supposedly fixed in Qt 5.9.2 however it has been reported with
# 5.10 and 5.11 as well. The initial workaround was to delete the directory
# in the Xsetup script but that doesn't do anything.
# Instead we use tmpfiles.d to ensure it gets wiped.
# This causes a small but perceptible delay when SDDM starts.
"e ${config.users.users.sddm.home}/.cache - - - 0"
];
};
}