path: root/libindicator/indicator-service.c

#ifdef HAVE_CONFIG_H
#include "config.h"
#endif
#include <dbus/dbus-glib-bindings.h>
#include <dbus/dbus-glib-lowlevel.h>

#include "indicator-service.h"

/* DBus Prototypes */
static gboolean _indicator_service_server_watch (IndicatorService * service, DBusGMethodInvocation * method);
static gboolean _indicator_service_server_un_watch (IndicatorService * service, DBusGMethodInvocation * method);

#include "indicator-service-server.h"
#include "dbus-shared.h"

/* Private Stuff */
typedef struct _IndicatorServicePrivate IndicatorServicePrivate;

struct _IndicatorServicePrivate {
	gchar * name;
	DBusGProxy * dbus_proxy;
	guint timeout;
	GList * watchers;
	guint this_service_version;
};

/* Signals Stuff */
enum {
	SHUTDOWN,
	LAST_SIGNAL
};

static guint signals[LAST_SIGNAL] = { 0 };

/* Properties */
/* Enum for the properties so that they can be quickly
   found and looked up. */
enum {
	PROP_0,
	PROP_NAME,
	PROP_VERSION
};

/* The strings so that they can be slowly looked up. */
#define PROP_NAME_S                    "name"
#define PROP_VERSION_S                 "version"

/* GObject Stuff */
#define INDICATOR_SERVICE_GET_PRIVATE(o) \
			(G_TYPE_INSTANCE_GET_PRIVATE ((o), INDICATOR_SERVICE_TYPE, IndicatorServicePrivate))

static void indicator_service_class_init (IndicatorServiceClass *klass);
static void indicator_service_init       (IndicatorService *self);
static void indicator_service_dispose    (GObject *object);
static void indicator_service_finalize   (GObject *object);

/* Other prototypes */
static void set_property (GObject * object, guint prop_id, const GValue * value, GParamSpec * pspec);
static void get_property (GObject * object, guint prop_id, GValue * value, GParamSpec * pspec);
static void try_and_get_name (IndicatorService * service);

G_DEFINE_TYPE (IndicatorService, indicator_service, G_TYPE_OBJECT);

static void
indicator_service_class_init (IndicatorServiceClass *klass)
{
	GObjectClass *object_class = G_OBJECT_CLASS (klass);

	g_type_class_add_private (klass, sizeof (IndicatorServicePrivate));

	object_class->dispose = indicator_service_dispose;
	object_class->finalize = indicator_service_finalize;

	/* Property funcs */
	object_class->set_property = set_property;
	object_class->get_property = get_property;

	/* Properties */
	g_object_class_install_property(object_class, PROP_NAME,
	                                g_param_spec_string(PROP_NAME_S,
	                                                    "The DBus name for this service",
	                                                    "This is the name that should be used on DBus for this service.",
	                                                    NULL,
	                                                    G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));
	g_object_class_install_property(object_class, PROP_VERSION,
	                                g_param_spec_uint(PROP_VERSION_S,
	                                                  "The version of the service that we're implementing.",
	                                                  "A number to represent the version of the other APIs the service provides.  This should match across the manager and the service",
	                                                  0, G_MAXUINT, 0,
	                                                  G_PARAM_READWRITE | G_PARAM_STATIC_STRINGS));

	/* Signals */

	/**
		IndicatorService::shutdown:
		@arg0: The #IndicatorService object
		
		Signaled when the service should shutdown as no one
		is listening anymore.
	*/
	signals[SHUTDOWN] = g_signal_new (INDICATOR_SERVICE_SIGNAL_SHUTDOWN,
	                                  G_TYPE_FROM_CLASS(klass),
	                                  G_SIGNAL_RUN_LAST,
	                                  G_STRUCT_OFFSET (IndicatorServiceClass, shutdown),
	                                  NULL, NULL,
	                                  g_cclosure_marshal_VOID__VOID,
	                                  G_TYPE_NONE, 0, G_TYPE_NONE);

	/* Initialize the object as a DBus type */
	dbus_g_object_type_install_info(INDICATOR_SERVICE_TYPE,
	                                &dbus_glib__indicator_service_server_object_info);

	return;
}

static void
indicator_service_init (IndicatorService *self)
{
	IndicatorServicePrivate * priv = INDICATOR_SERVICE_GET_PRIVATE(self);

	/* Get the private variables in a decent state */
	priv->name = NULL;
	priv->dbus_proxy = NULL;
	priv->timeout = 0;
	priv->watchers = NULL;
	priv->this_service_version = 0;

	/* Start talkin' dbus */
	GError * error = NULL;
	DBusGConnection * bus = dbus_g_bus_get(DBUS_BUS_STARTER, &error);
	if (error != NULL) {
		g_error("Unable to get starter bus: %s", error->message);
		g_error_free(error);

		/* Okay, fine let's try the session bus then. */
		/* I think this should automatically, but I can't find confirmation
		   of that, so we're putting the extra little code in here. */
		error = NULL;
		bus = dbus_g_bus_get(DBUS_BUS_SESSION, &error);
		if (error != NULL) {
			g_error("Unable to get session bus: %s", error->message);
			g_error_free(error);
			return;
		}
	}

	priv->dbus_proxy = dbus_g_proxy_new_for_name_owner(bus,
	                                                   DBUS_SERVICE_DBUS,
	                                                   DBUS_PATH_DBUS,
	                                                   DBUS_INTERFACE_DBUS,
	                                                   &error);
	if (error != NULL) {
		g_error("Unable to get the proxy to DBus: %s", error->message);
		g_error_free(error);
		return;
	}

	dbus_g_connection_register_g_object(bus,
	                                    INDICATOR_SERVICE_OBJECT,
	                                    G_OBJECT(self));

	return;
}

static void
indicator_service_dispose (GObject *object)
{
	IndicatorServicePrivate * priv = INDICATOR_SERVICE_GET_PRIVATE(object);

	if (priv->dbus_proxy != NULL) {
		g_object_unref(G_OBJECT(priv->dbus_proxy));
		priv->dbus_proxy = NULL;
	}

	if (priv->timeout != 0) {
		g_source_remove(priv->timeout);
		priv->timeout = 0;
	}

	G_OBJECT_CLASS (indicator_service_parent_class)->dispose (object);
	return;
}

static void
indicator_service_finalize (GObject *object)
{
	IndicatorServicePrivate * priv = INDICATOR_SERVICE_GET_PRIVATE(object);

	if (priv->name != NULL) {
		g_free(priv->name);
	}

	if (priv->watchers != NULL) {
		g_list_foreach(priv->watchers, (GFunc)g_free, NULL);
		g_list_free(priv->watchers);
		priv->watchers = NULL;
	}

	G_OBJECT_CLASS (indicator_service_parent_class)->finalize (object);
	return;
}

static void
set_property (GObject * object, guint prop_id, const GValue * value, GParamSpec * pspec)
{
	IndicatorService * self = INDICATOR_SERVICE(object);
	g_return_if_fail(self != NULL);

	IndicatorServicePrivate * priv = INDICATOR_SERVICE_GET_PRIVATE(self);
	g_return_if_fail(priv != NULL);

	switch (prop_id) {
	/* *********************** */
	case PROP_NAME:
		if (G_VALUE_HOLDS_STRING(value)) {
			if (priv->name != NULL) {
				g_error("Name can not be set twice!");
				return;
			}
			priv->name = g_value_dup_string(value);
			try_and_get_name(self);
		} else {
			g_warning("Name property requires a string value.");
		}
		break;
	/* *********************** */
	case PROP_VERSION:
		priv->this_service_version = g_value_get_uint(value);
		break;
	/* *********************** */
	default:
		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
		break;
	}

	return;
}

static void
get_property (GObject * object, guint prop_id, GValue * value, GParamSpec * pspec)
{
	IndicatorService * self = INDICATOR_SERVICE(object);
	g_return_if_fail(self != NULL);

	IndicatorServicePrivate * priv = INDICATOR_SERVICE_GET_PRIVATE(self);
	g_return_if_fail(priv != NULL);

	switch (prop_id) {
	/* *********************** */
	case PROP_NAME:
		if (G_VALUE_HOLDS_STRING(value)) {
			g_value_set_string(value, priv->name);
		} else {
			g_warning("Name property requires a string value.");
		}
		break;
	/* *********************** */
	case PROP_VERSION:
		g_value_set_uint(value, priv->this_service_version);
		break;
	/* *********************** */
	default:
		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, prop_id, pspec);
		break;
	}

	return;
}

static gboolean
timeout_no_watchers (gpointer data)
{
	g_signal_emit(G_OBJECT(data), signals[SHUTDOWN], 0, TRUE);
	return FALSE;
}

static void
try_and_get_name_cb (DBusGProxy * proxy, guint status, GError * error, gpointer data)
{
	IndicatorService * service = INDICATOR_SERVICE(data);
	g_return_if_fail(service != NULL);

	if (status != DBUS_REQUEST_NAME_REPLY_PRIMARY_OWNER && status != DBUS_REQUEST_NAME_REPLY_ALREADY_OWNER) {
		/* The already owner seems like it shouldn't ever
		   happen, but I have a hard time throwing an error
		   on it as we did achieve our goals. */
		g_signal_emit(G_OBJECT(data), signals[SHUTDOWN], 0, TRUE);
		return;
	}

	IndicatorServicePrivate * priv = INDICATOR_SERVICE_GET_PRIVATE(service);
	priv->timeout = g_timeout_add(500, timeout_no_watchers, service);

	return;
}

static void
try_and_get_name (IndicatorService * service)
{
	IndicatorServicePrivate * priv = INDICATOR_SERVICE_GET_PRIVATE(service);
	g_return_if_fail(priv->dbus_proxy != NULL);
	g_return_if_fail(priv->name != NULL);

	org_freedesktop_DBus_request_name_async(priv->dbus_proxy,
	                                        priv->name,
	                                        DBUS_NAME_FLAG_DO_NOT_QUEUE,
	                                        try_and_get_name_cb,
	                                        service);

	return;
}

static gboolean
_indicator_service_server_watch (IndicatorService * service, DBusGMethodInvocation * method)
{
	g_return_val_if_fail(INDICATOR_IS_SERVICE(service), FALSE);
	IndicatorServicePrivate * priv = INDICATOR_SERVICE_GET_PRIVATE(service);

	priv->watchers = g_list_append(priv->watchers,
	                               g_strdup(dbus_g_method_get_sender(method)));

	if (priv->timeout != 0) {
		g_source_remove(priv->timeout);
		priv->timeout = 0;
	}

	dbus_g_method_return(method, INDICATOR_SERVICE_VERSION, priv->this_service_version);
	return TRUE;
}

static gint
find_watcher (gconstpointer a, gconstpointer b)
{
	return g_strcmp0((const gchar *)a, (const gchar *)b);
}

static gboolean
_indicator_service_server_un_watch (IndicatorService * service, DBusGMethodInvocation * method)
{
	g_return_val_if_fail(INDICATOR_IS_SERVICE(service), FALSE);
	IndicatorServicePrivate * priv = INDICATOR_SERVICE_GET_PRIVATE(service);

	/* Remove us from the watcher list here */
	GList * watcher_item = g_list_find_custom(priv->watchers, dbus_g_method_get_sender(method), find_watcher);
	if (watcher_item != NULL) {
		/* Free the watcher */
		gchar * name = watcher_item->data;
		priv->watchers = g_list_remove(priv->watchers, name);
		g_free(name);
	} else {
		/* Odd that we couldn't find the person, but, eh */
		g_warning("Unable to find watcher who is unwatching: %s", dbus_g_method_get_sender(method));
	}

	/* If we're out of watchers set the timeout for shutdown */
	if (priv->watchers == NULL) {
		if (priv->timeout != 0) {
			/* This should never really happen, but let's ensure that
			   bad things don't happen if it does. */
			g_warning("No watchers timeout set twice.  Resolving, but odd.");
			g_source_remove(priv->timeout);
			priv->timeout = 0;
		}
		/* If we don't get a new watcher quickly, we'll shutdown. */
		priv->timeout = g_timeout_add(500, timeout_no_watchers, service);
	}

	dbus_g_method_return(method);
	return TRUE;
}

/* API */

/**
	indicator_service_new:
	@name: The name for the service on dbus

	This function creates the service on DBus and tries to
	get a well-known name specified in @name.  If the name
	can't be estabilished then the #IndicatorService::shutdown
	signal will be sent.

	Return value: A brand new #IndicatorService object or #NULL
		if there is an error.
*/
IndicatorService *
indicator_service_new (gchar * name)
{
	GObject * obj = g_object_new(INDICATOR_SERVICE_TYPE,
	                             PROP_NAME_S, name,
	                             NULL);

	return INDICATOR_SERVICE(obj);
}

/**
	indicator_service_new_version:
	@name: The name for the service on dbus
	@version: The version of the other interfaces provide
		by the service.

	This function creates the service on DBus and tries to
	get a well-known name specified in @name.  If the name
	can't be estabilished then the #IndicatorService::shutdown
	signal will be sent.

	Return value: A brand new #IndicatorService object or #NULL
		if there is an error.
*/
IndicatorService *
indicator_service_new_version (gchar * name, guint version)
{
	GObject * obj = g_object_new(INDICATOR_SERVICE_TYPE,
	                             PROP_NAME_S, name,
	                             PROP_VERSION_S, version,
	                             NULL);

	return INDICATOR_SERVICE(obj);
}