gala/daemon/Main.vala

//
//  Copyright (c) 2018 elementary LLC. (https://elementary.io)
//
//  This program is free software: you can redistribute it and/or modify
//  it under the terms of the GNU General Public License as published by
//  the Free Software Foundation, either version 3 of the License, or
//  (at your option) any later version.
//
//  This program is distributed in the hope that it will be useful,
//  but WITHOUT ANY WARRANTY; without even the implied warranty of
//  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
//  GNU General Public License for more details.
//
//  You should have received a copy of the GNU General Public License
//  along with this program.  If not, see <http://www.gnu.org/licenses/>.
//

namespace Gala
{
	[DBus (name = "org.gnome.SessionManager")]
	public interface SessionManager : Object
	{
		public abstract async ObjectPath register_client (string app_id, string client_start_id) throws DBusError, IOError;
	}

	[DBus (name = "org.gnome.SessionManager.ClientPrivate")]
	public interface SessionClient : Object
	{
		public abstract void end_session_response (bool is_ok, string reason) throws DBusError, IOError;

		public signal void stop () ;
		public signal void query_end_session (uint flags);
		public signal void end_session (uint flags);
		public signal void cancel_end_session ();
	}

	public class Daemon
	{
		SessionClient? sclient = null;

		public Daemon ()
		{
			register.begin ((o, res)=> {
				bool success = register.end (res);
				if (!success) {
					message ("Failed to register with Session manager");
				}
			});

			var menu_daemon = new MenuDaemon ();
			menu_daemon.setup_dbus ();
		}

		public void run () {
			Gtk.main ();
		}

		public static async SessionClient? register_with_session (string app_id)
		{
			ObjectPath? path = null;
			string? msg = null;
			string? start_id = null;

			SessionManager? session = null;
			SessionClient? session_client = null;

			start_id = Environment.get_variable ("DESKTOP_AUTOSTART_ID");
			if (start_id != null) {
				Environment.unset_variable ("DESKTOP_AUTOSTART_ID");
			} else {
				start_id = "";
				warning ("DESKTOP_AUTOSTART_ID not set, session registration may be broken (not running via session?)");
			}

			try {
				session = yield Bus.get_proxy (BusType.SESSION, "org.gnome.SessionManager", "/org/gnome/SessionManager");
			} catch (Error e) {
				warning ("Unable to connect to session manager: %s", e.message);
				return null;
			}

			try {
				path = yield session.register_client (app_id, start_id);
			} catch (Error e) {
				msg = e.message;
				warning ("Error registering with session manager: %s", e.message);
				return null;
			}

			try {
				session_client = yield Bus.get_proxy (BusType.SESSION, "org.gnome.SessionManager", path);
			} catch (Error e) {
				warning ("Unable to get private sessions client proxy: %s", e.message);
				return null;
			}

			return session_client;
		}

		async bool register ()
		{
			sclient = yield register_with_session ("org.pantheon.gala.daemon");

			sclient.query_end_session.connect (() => end_session (false));
			sclient.end_session.connect (() => end_session (false));
			sclient.stop.connect (() => end_session (true));

			return true;
		}

		void end_session (bool quit)
		{
			if (quit) {
				Gtk.main_quit ();
				return;
			}

			try {
				sclient.end_session_response (true, "");
			} catch (Error e) {
				warning ("Unable to respond to session manager: %s", e.message);
			}
		}
	}

	public static int main (string[] args)
	{
		Gtk.init (ref args);

		var ctx = new OptionContext ("Gala Daemon");
		ctx.set_help_enabled (true);
		ctx.add_group (Gtk.get_option_group (false));

		try {
			ctx.parse (ref args);
		} catch (Error e) {
			stderr.printf ("Error: %s\n", e.message);
			return 0;
		}

		var daemon = new Daemon ();
		daemon.run ();

		return 0;
	}
}