core: explicitly unexport objects when we're done with them

Previously most objects were implicitly unexported when they were
destroyed, but since refcounts may make the object live longer than
intended, we should explicitly unexport them when they should no
longer be present on the bus.

This means we can assume that objects will always be un-exported
already when they are destroyed, *except* when quitting where most
objects will live until exit because NM leaves interfaces up and
running on quit.

src/devices/adsl/nm-device-adsl.c

@@ -441,8 +441,7 @@ act_stage3_ip4_config_start (NMDevice *device,
 		_LOGW (LOGD_ADSL, "PPP failed to start: %s", err->message);
 		g_error_free (err);
 
-		g_object_unref (priv->ppp_manager);
+		nm_exported_object_clear_and_unexport (&priv->ppp_manager);
-		priv->ppp_manager = NULL;
 
 		*reason = NM_DEVICE_STATE_REASON_PPP_START_FAILED;
 	}
@@ -456,10 +455,7 @@ deactivate (NMDevice *device)
 	NMDeviceAdsl *self = NM_DEVICE_ADSL (device);
 	NMDeviceAdslPrivate *priv = NM_DEVICE_ADSL_GET_PRIVATE (self);
 
-	if (priv->ppp_manager) {
+	nm_exported_object_clear_and_unexport (&priv->ppp_manager);
-		g_object_unref (priv->ppp_manager);
-		priv->ppp_manager = NULL;
-	}
 
 	g_signal_handlers_disconnect_by_func (nm_platform_get (), G_CALLBACK (link_changed_cb), device);
 

src/devices/nm-device-ethernet.c

@@ -1010,8 +1010,7 @@ pppoe_stage3_ip4_config_start (NMDeviceEthernet *self, NMDeviceStateReason *reas
 		_LOGW (LOGD_DEVICE, "PPPoE failed to start: %s", err->message);
 		g_error_free (err);
 
-		g_object_unref (priv->ppp_manager);
+		nm_exported_object_clear_and_unexport (&priv->ppp_manager);
-		priv->ppp_manager = NULL;
 
 		*reason = NM_DEVICE_STATE_REASON_PPP_START_FAILED;
 	}
@@ -1399,10 +1398,7 @@ deactivate (NMDevice *device)
 		priv->pending_ip4_config = NULL;
 	}
 
-	if (priv->ppp_manager) {
+	nm_exported_object_clear_and_unexport (&priv->ppp_manager);
-		g_object_unref (priv->ppp_manager);
-		priv->ppp_manager = NULL;
-	}
 
 	supplicant_interface_release (self);
 

src/devices/nm-device.c

@@ -3581,7 +3581,7 @@ dhcp4_cleanup (NMDevice *self, CleanupType cleanup_type, gboolean release)
 	}
 
 	if (priv->dhcp4_config) {
-		g_clear_object (&priv->dhcp4_config);
+		nm_exported_object_clear_and_unexport (&priv->dhcp4_config);
 		g_object_notify (G_OBJECT (self), NM_DEVICE_DHCP4_CONFIG);
 	}
 }
@@ -3938,8 +3938,7 @@ dhcp4_start (NMDevice *self,
 	s_ip4 = nm_connection_get_setting_ip4_config (connection);
 
 	/* Clear old exported DHCP options */
-	if (priv->dhcp4_config)
+	nm_exported_object_clear_and_unexport (&priv->dhcp4_config);
-		g_object_unref (priv->dhcp4_config);
 	priv->dhcp4_config = nm_dhcp4_config_new ();
 
 	hw_addr = nm_platform_link_get_address (NM_PLATFORM_GET, nm_device_get_ip_ifindex (self), &hw_addr_len);
@@ -4275,7 +4274,7 @@ dhcp6_cleanup (NMDevice *self, CleanupType cleanup_type, gboolean release)
 	nm_device_remove_pending_action (self, PENDING_ACTION_DHCP6, FALSE);
 
 	if (priv->dhcp6_config) {
-		g_clear_object (&priv->dhcp6_config);
+		nm_exported_object_clear_and_unexport (&priv->dhcp6_config);
 		g_object_notify (G_OBJECT (self), NM_DEVICE_DHCP6_CONFIG);
 	}
 }
@@ -4700,7 +4699,7 @@ dhcp6_start (NMDevice *self, gboolean wait_for_ll, NMDeviceStateReason *reason)
 	NMConnection *connection;
 	NMSettingIPConfig *s_ip6;
 
-	g_clear_object (&priv->dhcp6_config);
+	nm_exported_object_clear_and_unexport (&priv->dhcp6_config);
 	priv->dhcp6_config = nm_dhcp6_config_new ();
 
 	g_warn_if_fail (priv->dhcp6_ip6_config == NULL);
@@ -6864,8 +6863,8 @@ nm_device_set_ip4_config (NMDevice *self,
 			g_object_notify (G_OBJECT (self), NM_DEVICE_IP4_CONFIG);
 		g_signal_emit (self, signals[IP4_CONFIG_CHANGED], 0, priv->ip4_config, old_config);
 
-		if (old_config != priv->ip4_config && old_config)
+		if (old_config != priv->ip4_config)
-			g_object_unref (old_config);
+			nm_exported_object_clear_and_unexport (&old_config);
 
 		if (nm_device_uses_generated_assumed_connection (self)) {
 			NMConnection *connection = nm_device_get_applied_connection (self);
@@ -7031,8 +7030,8 @@ nm_device_set_ip6_config (NMDevice *self,
 			g_object_notify (G_OBJECT (self), NM_DEVICE_IP6_CONFIG);
 		g_signal_emit (self, signals[IP6_CONFIG_CHANGED], 0, priv->ip6_config, old_config);
 
-		if (old_config != priv->ip6_config && old_config)
+		if (old_config != priv->ip6_config)
-			g_object_unref (old_config);
+			nm_exported_object_clear_and_unexport (&old_config);
 
 		if (nm_device_uses_generated_assumed_connection (self)) {
 			NMConnection *connection = nm_device_get_applied_connection (self);

src/devices/wwan/nm-modem.c

@@ -530,8 +530,7 @@ ppp_stage3_ip_config_start (NMModem *self,
 		            error && error->message ? error->message : "(unknown)");
 		g_error_free (error);
 
-		g_object_unref (priv->ppp_manager);
+		nm_exported_object_clear_and_unexport (&priv->ppp_manager);
-		priv->ppp_manager = NULL;
 
 		*reason = NM_DEVICE_STATE_REASON_PPP_START_FAILED;
 		ret = NM_ACT_STAGE_RETURN_FAILURE;
@@ -885,10 +884,7 @@ deactivate_cleanup (NMModem *self, NMDevice *device)
 
 	priv->in_bytes = priv->out_bytes = 0;
 
-	if (priv->ppp_manager) {
+	nm_exported_object_clear_and_unexport (&priv->ppp_manager);
-		g_object_unref (priv->ppp_manager);
-		priv->ppp_manager = NULL;
-	}
 
 	if (device) {
 		g_return_if_fail (NM_IS_DEVICE (device));

src/main.c

@@ -50,6 +50,7 @@
 #include "nm-settings.h"
 #include "nm-auth-manager.h"
 #include "nm-core-internal.h"
+#include "nm-exported-object.h"
 
 #if !defined(NM_DIST_VERSION)
 # define NM_DIST_VERSION VERSION
@@ -454,6 +455,8 @@ main (int argc, char *argv[])
 	if (configure_and_quit == FALSE)
 		g_main_loop_run (main_loop);
 
+	nm_exported_object_class_set_quitting ();
+
 	nm_manager_stop (nm_manager_get ());
 
 done:

src/nm-exported-object.c

@@ -28,6 +28,8 @@
 #include "nm-default.h"
 
 static GHashTable *prefix_counters;
+static gboolean quitting = FALSE;
+
 
 #if NM_MORE_ASSERTS >= 2
 #define _ASSERT_NO_EARLY_EXPORT
@@ -632,6 +634,28 @@ nm_exported_object_get_interface_by_type (NMExportedObject *self, GType interfac
 	return NULL;
 }
 
+void
+_nm_exported_object_clear_and_unexport (NMExportedObject **location)
+{
+	NMExportedObject *self;
+	NMExportedObjectPrivate *priv;
+
+	if (!location || !*location)
+		return;
+
+	self = *location;
+	*location = NULL;
+
+	g_return_if_fail (NM_IS_EXPORTED_OBJECT (self));
+
+	priv = NM_EXPORTED_OBJECT_GET_PRIVATE (self);
+
+	if (priv->path)
+		nm_exported_object_unexport (self);
+
+	g_object_unref (self);
+}
+
 static void
 nm_exported_object_init (NMExportedObject *self)
 {
@@ -765,8 +789,16 @@ nm_exported_object_dispose (GObject *object)
 {
 	NMExportedObjectPrivate *priv = NM_EXPORTED_OBJECT_GET_PRIVATE (object);
 
-	if (priv->path)
+	/* Objects should have already been unexported by their owner, unless
-		nm_exported_object_unexport (NM_EXPORTED_OBJECT (object));
+	 * we are quitting, where many objects stick around until exit.
+	 */
+	if (!quitting) {
+		if (priv->path) {
+			g_warn_if_reached ();
+			nm_exported_object_unexport (NM_EXPORTED_OBJECT (object));
+		}
+	} else
+		g_clear_pointer (&priv->path, g_free);
 
 	g_variant_builder_clear (&priv->pending_notifies);
 	nm_clear_g_source (&priv->notify_idle_id);
@@ -785,3 +817,10 @@ nm_exported_object_class_init (NMExportedObjectClass *klass)
 	object_class->notify = nm_exported_object_notify;
 	object_class->dispose = nm_exported_object_dispose;
 }
+
+void
+nm_exported_object_class_set_quitting (void)
+{
+	quitting = TRUE;
+}
+

src/nm-exported-object.h

@@ -45,6 +45,8 @@ typedef struct {
 
 GType nm_exported_object_get_type (void);
 
+void nm_exported_object_class_set_quitting  (void);
+
 void nm_exported_object_class_add_interface (NMExportedObjectClass *object_class,
                                              GType                  dbus_skeleton_type,
                                              ...) G_GNUC_NULL_TERMINATED;
@@ -56,6 +58,9 @@ void        nm_exported_object_unexport    (NMExportedObject *self);
 GSList *    nm_exported_object_get_interfaces (NMExportedObject *self);
 GDBusInterfaceSkeleton *nm_exported_object_get_interface_by_type (NMExportedObject *self, GType interface_type);
 
+void        _nm_exported_object_clear_and_unexport (NMExportedObject **location);
+#define nm_exported_object_clear_and_unexport(location) _nm_exported_object_clear_and_unexport ((NMExportedObject **) (location))
+
 G_END_DECLS
 
 #endif	/* NM_EXPORTED_OBJECT_H */

src/nm-manager.c

@@ -225,7 +225,7 @@ active_connection_remove (NMManager *self, NMActiveConnection *active)
 		else
 			connection = NULL;
 
-		g_object_unref (active);
+		nm_exported_object_clear_and_unexport (&active);
 
 		if (   connection
 		    && nm_settings_has_connection (priv->settings, connection)) {
@@ -801,8 +801,7 @@ remove_device (NMManager *manager,
 	g_object_notify (G_OBJECT (manager), NM_MANAGER_DEVICES);
 	nm_device_removed (device);
 
-	nm_exported_object_unexport (NM_EXPORTED_OBJECT (device));
+	nm_exported_object_clear_and_unexport (&device);
-	g_object_unref (device);
 
 	check_if_startup_complete (manager);
 }

src/settings/nm-settings-connection.c

@@ -2053,14 +2053,7 @@ nm_settings_connection_signal_remove (NMSettingsConnection *self)
 	if (priv->removed)
 		g_return_if_reached ();
 	priv->removed = TRUE;
-
-	/* Emit removed first */
 	g_signal_emit_by_name (self, NM_SETTINGS_CONNECTION_REMOVED);
-
-	/* And unregister last to ensure the removed signal goes out before
-	 * we take the connection off the bus.
-	 */
-	nm_exported_object_unexport (NM_EXPORTED_OBJECT (self));
 }
 
 gboolean

src/settings/nm-settings.c

@@ -905,6 +905,8 @@ connection_removed (NMSettingsConnection *connection, gpointer user_data)
 	/* Re-emit for listeners like NMPolicy */
 	g_signal_emit_by_name (self, NM_CP_SIGNAL_CONNECTION_REMOVED, connection);
 	g_object_notify (G_OBJECT (self), NM_SETTINGS_CONNECTIONS);
+	if (nm_exported_object_is_exported (NM_EXPORTED_OBJECT (connection)))
+		nm_exported_object_unexport (NM_EXPORTED_OBJECT (connection));
 
 	check_startup_complete (self);
 

src/vpn-manager/nm-vpn-connection.c

@@ -1117,8 +1117,8 @@ _cleanup_failed_config (NMVpnConnection *self)
 {
 	NMVpnConnectionPrivate *priv = NM_VPN_CONNECTION_GET_PRIVATE (self);
 
-	g_clear_object (&priv->ip4_config);
+	nm_exported_object_clear_and_unexport (&priv->ip4_config);
-	g_clear_object (&priv->ip6_config);
+	nm_exported_object_clear_and_unexport (&priv->ip6_config);
 
 	_LOGW ("VPN connection: did not receive valid IP config information");
 	_set_vpn_state (self, STATE_FAILED, NM_VPN_CONNECTION_STATE_REASON_IP_CONFIG_INVALID, FALSE);
@@ -1316,12 +1316,12 @@ nm_vpn_connection_config_get (NMVpnConnection *self, GVariant *dict)
 	priv->has_ip4 = FALSE;
 	if (g_variant_lookup (dict, NM_VPN_PLUGIN_CONFIG_HAS_IP4, "b", &b))
 		priv->has_ip4 = b;
-	g_clear_object (&priv->ip4_config);
+	nm_exported_object_clear_and_unexport (&priv->ip4_config);
 
 	priv->has_ip6 = FALSE;
 	if (g_variant_lookup (dict, NM_VPN_PLUGIN_CONFIG_HAS_IP6, "b", &b))
 		priv->has_ip6 = b;
-	g_clear_object (&priv->ip6_config);
+	nm_exported_object_clear_and_unexport (&priv->ip6_config);
 }
 
 guint32
@@ -1491,7 +1491,7 @@ nm_vpn_connection_ip4_config_get (NMVpnConnection *self, GVariant *dict)
 	                             nm_connection_get_setting_ip4_config (_get_applied_connection (self)),
 	                             route_metric);
 
-	g_clear_object (&priv->ip4_config);
+	nm_exported_object_clear_and_unexport (&priv->ip4_config);
 	priv->ip4_config = config;
 	nm_exported_object_export (NM_EXPORTED_OBJECT (config));
 	g_object_notify (G_OBJECT (self), NM_ACTIVE_CONNECTION_IP4_CONFIG);
@@ -1626,7 +1626,7 @@ next:
 	                             nm_connection_get_setting_ip6_config (_get_applied_connection (self)),
 	                             route_metric);
 
-	g_clear_object (&priv->ip6_config);
+	nm_exported_object_clear_and_unexport (&priv->ip6_config);
 	priv->ip6_config = config;
 	nm_exported_object_export (NM_EXPORTED_OBJECT (config));
 	g_object_notify (G_OBJECT (self), NM_ACTIVE_CONNECTION_IP6_CONFIG);
@@ -2444,8 +2444,8 @@ dispose (GObject *object)
 		g_cancellable_cancel (priv->cancellable);
 		g_clear_object (&priv->cancellable);
 	}
-	g_clear_object (&priv->ip4_config);
+	nm_exported_object_clear_and_unexport (&priv->ip4_config);
-	g_clear_object (&priv->ip6_config);
+	nm_exported_object_clear_and_unexport (&priv->ip6_config);
 	g_clear_object (&priv->proxy);
 	g_clear_object (&priv->plugin_info);