dbus.c

Linux的蓝牙操作工具。配合bluez-lib使用

	if (dbus_message_is_signal(msg,
			DBUS_INTERFACE_LOCAL, "Disconnected") == TRUE) {
		error("Got disconnected from the system message bus");
		dbus_connection_unref(conn);
		dc_data->disconnect_cb(dc_data->user_data);
	}

	return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
}

#ifndef HAVE_DBUS_GLIB
static dbus_int32_t server_slot = -1;

static gboolean server_func(GIOChannel *chan, GIOCondition cond, gpointer data)
{
	DBusWatch *watch = data;
	int flags = 0;

	if (cond & G_IO_IN)  flags |= DBUS_WATCH_READABLE;
	if (cond & G_IO_OUT) flags |= DBUS_WATCH_WRITABLE;
	if (cond & G_IO_HUP) flags |= DBUS_WATCH_HANGUP;
	if (cond & G_IO_ERR) flags |= DBUS_WATCH_ERROR;

	dbus_watch_handle(watch, flags);

	return TRUE;
}

static dbus_bool_t add_server(DBusWatch *watch, void *data)
{
	GIOCondition cond = G_IO_HUP | G_IO_ERR;
	DBusServer *server = data;
	struct server_info *info;
	int fd, flags;

	if (!dbus_watch_get_enabled(watch))
		return TRUE;

	info = g_new(struct server_info, 1);

	fd = dbus_watch_get_unix_fd(watch);
	info->io = g_io_channel_unix_new(fd);
	info->server = dbus_server_ref(server);

	dbus_watch_set_data(watch, info, NULL);

	flags = dbus_watch_get_flags(watch);

	if (flags & DBUS_WATCH_READABLE) cond |= G_IO_IN;
	if (flags & DBUS_WATCH_WRITABLE) cond |= G_IO_OUT;

	info->watch_id = g_io_add_watch(info->io, cond, server_func, watch);

	return TRUE;
}

static void remove_server(DBusWatch *watch, void *data)
{
	struct server_info *info = dbus_watch_get_data(watch);

	dbus_watch_set_data(watch, NULL, NULL);

	if (info) {
		g_source_remove(info->watch_id);
		g_io_channel_unref(info->io);
		dbus_server_unref(info->server);
		g_free(info);
	}
}

static void server_toggled(DBusWatch *watch, void *data)
{
	/* Because we just exit on OOM, enable/disable is
	 * no different from add/remove */
	if (dbus_watch_get_enabled(watch))
		add_server(watch, data);
	else
		remove_server(watch, data);
}

static gboolean message_dispatch_cb(void *data)
{
	DBusConnection *connection = data;

	dbus_connection_ref(connection);

	/* Dispatch messages */
	while (dbus_connection_dispatch(connection) == DBUS_DISPATCH_DATA_REMAINS);

	dbus_connection_unref(connection);

	return FALSE;
}

static gboolean watch_func(GIOChannel *chan, GIOCondition cond, gpointer data)
{
	DBusWatch *watch = data;
	struct watch_info *info = dbus_watch_get_data(watch);
	int flags = 0;

	if (cond & G_IO_IN)  flags |= DBUS_WATCH_READABLE;
	if (cond & G_IO_OUT) flags |= DBUS_WATCH_WRITABLE;
	if (cond & G_IO_HUP) flags |= DBUS_WATCH_HANGUP;
	if (cond & G_IO_ERR) flags |= DBUS_WATCH_ERROR;

	dbus_watch_handle(watch, flags);

	if (dbus_connection_get_dispatch_status(info->conn) == DBUS_DISPATCH_DATA_REMAINS)
		g_timeout_add(DISPATCH_TIMEOUT, message_dispatch_cb, info->conn);

	return TRUE;
}

static dbus_bool_t add_watch(DBusWatch *watch, void *data)
{
	GIOCondition cond = G_IO_HUP | G_IO_ERR;
	DBusConnection *conn = data;
	struct watch_info *info;
	int fd, flags;

	if (!dbus_watch_get_enabled(watch))
		return TRUE;

	info = g_new(struct watch_info, 1);

	fd = dbus_watch_get_unix_fd(watch);
	info->io = g_io_channel_unix_new(fd);
	info->conn = dbus_connection_ref(conn);

	dbus_watch_set_data(watch, info, NULL);

	flags = dbus_watch_get_flags(watch);

	if (flags & DBUS_WATCH_READABLE) cond |= G_IO_IN;
	if (flags & DBUS_WATCH_WRITABLE) cond |= G_IO_OUT;

	info->watch_id = g_io_add_watch(info->io, cond, watch_func, watch);

	return TRUE;
}

static void remove_watch(DBusWatch *watch, void *data)
{
	struct watch_info *info = dbus_watch_get_data(watch);

	dbus_watch_set_data(watch, NULL, NULL);

	if (info) {
		g_source_remove(info->watch_id);
		g_io_channel_unref(info->io);
		dbus_connection_unref(info->conn);
		g_free(info);
	}
}

static void watch_toggled(DBusWatch *watch, void *data)
{
	/* Because we just exit on OOM, enable/disable is
	 * no different from add/remove */
	if (dbus_watch_get_enabled(watch))
		add_watch(watch, data);
	else
		remove_watch(watch, data);
}

static gboolean timeout_handler_dispatch(gpointer data)
{
	timeout_handler_t *handler = data;

	/* if not enabled should not be polled by the main loop */
	if (dbus_timeout_get_enabled(handler->timeout) != TRUE)
		return FALSE;

	dbus_timeout_handle(handler->timeout);

	return FALSE;
}

static void timeout_handler_free(void *data)
{
	timeout_handler_t *handler = data;
	if (!handler)
		return;

	g_source_remove(handler->id);
	g_free(handler);
}

static dbus_bool_t add_timeout(DBusTimeout *timeout, void *data)
{
	timeout_handler_t *handler;

	if (!dbus_timeout_get_enabled(timeout))
		return TRUE;

	handler = g_new0(timeout_handler_t, 1);

	handler->timeout = timeout;
	handler->id = g_timeout_add(dbus_timeout_get_interval(timeout),
					timeout_handler_dispatch, handler);

	dbus_timeout_set_data(timeout, handler, timeout_handler_free);

	return TRUE;
}

static void remove_timeout(DBusTimeout *timeout, void *data)
{
}

static void timeout_toggled(DBusTimeout *timeout, void *data)
{
	if (dbus_timeout_get_enabled(timeout))
		add_timeout(timeout, data);
	else
		remove_timeout(timeout, data);
}

static void dispatch_status_cb(DBusConnection *conn,
				DBusDispatchStatus new_status, void *data)
{
	if (!dbus_connection_get_is_connected(conn))
		return;

	if (new_status == DBUS_DISPATCH_DATA_REMAINS)
		g_timeout_add(DISPATCH_TIMEOUT, message_dispatch_cb, data);
}
#endif

void setup_dbus_server_with_main_loop(DBusServer *server)
{
#ifdef HAVE_DBUS_GLIB
	debug("Using D-Bus GLib server setup");

	dbus_server_setup_with_g_main(server, NULL);
#else
	dbus_server_allocate_data_slot(&server_slot);
	if (server_slot < 0)
		return;

	dbus_server_set_data(server, server_slot, server, NULL);

	dbus_server_set_watch_functions(server, add_server, remove_server,
						server_toggled, server, NULL);

	dbus_server_set_timeout_functions(server, add_timeout, remove_timeout,
						timeout_toggled, server, NULL);
#endif
}

void setup_dbus_with_main_loop(DBusConnection *conn)
{
#ifdef HAVE_DBUS_GLIB
	debug("Using D-Bus GLib connection setup");

	dbus_connection_setup_with_g_main(conn, NULL);
#else
	dbus_connection_set_watch_functions(conn, add_watch, remove_watch,
						watch_toggled, conn, NULL);

	dbus_connection_set_timeout_functions(conn, add_timeout, remove_timeout,
						timeout_toggled, conn, NULL);

	dbus_connection_set_dispatch_status_function(conn, dispatch_status_cb,
								conn, NULL);
#endif
}

DBusConnection *init_dbus(const char *name,
				void (*disconnect_cb)(void *), void *user_data)
{
	struct disconnect_data *dc_data;
	DBusConnection *conn;
	DBusError err;

	dbus_error_init(&err);

	conn = dbus_bus_get(DBUS_BUS_SYSTEM, &err);

	if (dbus_error_is_set(&err)) {
		error("Can't connect to system message bus: %s", err.message);
		dbus_error_free(&err);
		return NULL;
	}

	setup_dbus_with_main_loop(conn);

	if (name) {
		dbus_error_init(&err);

		if (dbus_bus_request_name(conn, name, 0, &err) !=
				DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER ) {
			error("Could not become the primary owner of %s", name);
			dbus_connection_unref(conn);
			return NULL;
		}

		if (dbus_error_is_set(&err)) {
			error("Can't get bus name %s: %s", name, err.message);
			dbus_error_free(&err);
			dbus_connection_unref(conn);
			return NULL;
		}
	}

	if (!disconnect_cb)
		return conn;

	dc_data = g_new(struct disconnect_data, 1);

	dc_data->disconnect_cb = disconnect_cb;
	dc_data->user_data = user_data;

	dbus_connection_set_exit_on_disconnect(conn, FALSE);

	if (!dbus_connection_add_filter(conn, disconnect_filter,
				dc_data, g_free)) {
		error("Can't add D-Bus disconnect filter");
		g_free(dc_data);
		dbus_connection_unref(conn);
		return NULL;
	}

	return conn;
}

DBusConnection *init_dbus_direct(const char *address)
{
	DBusConnection *conn;
	DBusError err;

	dbus_error_init(&err);

	conn = dbus_connection_open(address, &err);

	if (dbus_error_is_set(&err)) {
		error("Can't connect to message server: %s", err.message);
		dbus_error_free(&err);
		return NULL;
	}

	setup_dbus_with_main_loop(conn);

	dbus_connection_set_exit_on_disconnect(conn, FALSE);

	return conn;
}

DBusConnection *dbus_bus_system_setup_with_main_loop(const char *name,
				void (*disconnect_cb)(void *), void *user_data)
{
	return init_dbus(name, disconnect_cb, user_data);
}

static char simple_xml[] = DBUS_INTROSPECT_1_0_XML_DOCTYPE_DECL_NODE "<node></node>";

DBusHandlerResult simple_introspect(DBusConnection *conn,
					DBusMessage *msg, void *user_data)
{
	DBusMessage *reply;
	const char *path, *ptr = simple_xml;

	path = dbus_message_get_path(msg);

	info("Introspect path:%s", path);

	if (!dbus_message_has_signature(msg, DBUS_TYPE_INVALID_AS_STRING)) {
		error("Unexpected signature to introspect call");
		return DBUS_HANDLER_RESULT_NOT_YET_HANDLED;
	}

	reply = dbus_message_new_method_return(msg);
	if (!reply)
		return DBUS_HANDLER_RESULT_NEED_MEMORY;

	dbus_message_append_args(reply, DBUS_TYPE_STRING, &ptr,
					DBUS_TYPE_INVALID);

	return send_message_and_unref(conn, reply);
}

int set_nonblocking(int fd)
{
	long arg;

	arg = fcntl(fd, F_GETFL);
	if (arg < 0) {
		error("fcntl(F_GETFL): %s (%d)", strerror(errno), errno);
		return -errno;
	}

	/* Return if already nonblocking */
	if (arg & O_NONBLOCK)
		return 0;

	arg |= O_NONBLOCK;
	if (fcntl(fd, F_SETFL, arg) < 0) {
		error("fcntl(F_SETFL, O_NONBLOCK): %s (%d)",
				strerror(errno), errno);
		return -errno;
	}

	return 0;
}

void register_external_service(DBusConnection *conn, const char *identifier,
				const char *name, const char *description)
{
	DBusMessage *msg, *reply;

	info("Registering service");

	msg = dbus_message_new_method_call("org.bluez", "/org/bluez",
				"org.bluez.Database", "RegisterService");
	if (!msg) {
		error("Can't create service register method");
		return;
	}

	dbus_message_append_args(msg, DBUS_TYPE_STRING, &identifier,
			DBUS_TYPE_STRING, &name,
			DBUS_TYPE_STRING, &description, DBUS_TYPE_INVALID);

	reply = dbus_connection_send_with_reply_and_block(conn, msg, -1, NULL);
	if (!reply) {
		error("Can't register service");
		return;
	}

	dbus_message_unref(msg);
	dbus_message_unref(reply);

	dbus_connection_flush(conn);
}