Ck.cpp

/*
 * SLiM - Simple Login Manager
 * Copyright (C) 2011 David Hauweele
 *
 * 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 2 of the License, or
 * (at your option) any later version.
 */

#include <cstdio>
#include <iostream>

#include <X11/Xatom.h>
#include <X11/Xlib.h>
#include <ck-connector.h>
#include <stdarg.h>

#include "Ck.h"

namespace Ck
{
	Exception::Exception(const std::string & func, const std::string & errstr)
		: func(func), errstr(errstr)
	{
	}

	dbus_bool_t Session::ck_connector_open_graphic_session(
		const std::string & display, uid_t uid)
	{
		dbus_bool_t local = true;
		const char * session_type = "x11";
		const char * x11_display = display.c_str();
		const char * x11_device = get_x11_device(display);
		const char * remote_host = "";
		const char * display_dev = "";

		return ck_connector_open_session_with_parameters(ckc, &error,
			"unix-user", &uid, "session-type", &session_type, "x11-display",
			&x11_display, "x11-display-device", &x11_device, "display-device",
			&display_dev, "remote-host-name", &remote_host, "is-local", &local,
			NULL);
	}

	const char * Session::get_x11_device(const std::string & display)
	{
		static char device[32];

		Display * xdisplay = XOpenDisplay(display.c_str());

		if (!xdisplay)
			throw Exception(__func__, "cannot open display");

		Window root;
		Atom xfree86_vt_atom;
		Atom return_type_atom;
		int return_format;
		unsigned long return_count;
		unsigned long bytes_left;
		unsigned char * return_value;
		long vt;

		xfree86_vt_atom = XInternAtom(xdisplay, "XFree86_VT", true);

		if (xfree86_vt_atom == None)
			throw Exception(__func__, "cannot get XFree86_VT");

		root = DefaultRootWindow(xdisplay);

		if (XGetWindowProperty(xdisplay, root, xfree86_vt_atom, 0L, 1L, false,
				XA_INTEGER, &return_type_atom, &return_format, &return_count,
				&bytes_left, &return_value) != Success)
			throw Exception(__func__, "cannot get root window property");

		if (return_type_atom != XA_INTEGER)
			throw Exception(__func__, "bad atom type");

		if (return_format != 32)
			throw Exception(__func__, "invalid return format");

		if (return_count != 1)
			throw Exception(__func__, "invalid count");

		if (bytes_left != 0)
			throw Exception(__func__, "invalid bytes left");

		vt = *((long *)return_value);

		std::snprintf(device, 32, "/dev/tty%ld", vt);

		if (return_value)
			XFree(return_value);

		return device;
	}

	void Session::open_session(const std::string & display, uid_t uid)
	{
		ckc = ck_connector_new();

		if (!ckc)
			throw Exception(
				__func__, "error setting up connection to ConsoleKit");

		if (!ck_connector_open_graphic_session(display, uid)) {
			if (dbus_error_is_set(&error))
				throw Exception(__func__, error.message);
			else
				throw Exception(__func__,
					"cannot open ConsoleKit session: OOM,"
					" DBus system bus not available or insufficient"
					" privileges");
		}
	}

	const char * Session::get_xdg_session_cookie()
	{
		return ck_connector_get_cookie(ckc);
	}

	void Session::close_session()
	{
		if (!ck_connector_close_session(ckc, &error)) {
			if (dbus_error_is_set(&error))
				throw Exception(__func__, error.message);
			else
				throw Exception(__func__,
					"cannot close ConsoleKit session: OOM,"
					" DBus system bus not available or insufficient"
					" privileges");
		}
	}

	Session::Session() { dbus_error_init(&error); }

	Session::~Session() { dbus_error_free(&error); }
} // namespace Ck

std::ostream & operator<<(std::ostream & os, const Ck::Exception & e)
{
	os << e.func << ": " << e.errstr;
	return os;
}