iwd: Subscribe to object-added/removed ObjectManager signals

GDBusObjectManagerClient's interface-added and interface-removed signals
are not emitted when the new interfaces are added to a completely new
object or the removal results in the object disappearing.  In other
words one interface is never reported both through interface-added and
object-added (or -removed) signals.  This kind of makes sense but isn't
documented explicitly so interface-added seemed to correspond to DBus
InterfacesAdded signals which it doesn't.

We need to watch for both kinds of signals and although most things
work without us receiving the signals at all, it causes some race
conditions.  For example on hotplug, devices wouldn't transition to
"disconnected" if a device was discovered by NMManager before it
appeared on IWD's dbus interface because that scenario relied on the
dbus signal.

1 files changed, 35 insertions, 17 deletions

diff --git a/src/devices/wifi/nm-iwd-manager.c b/src/devices/wifi/nm-iwd-manager.c
index bdff20ac9f..6a56201440 100644
--- a/src/devices/wifi/nm-iwd-manager.c
+++ b/src/devices/wifi/nm-iwd-manager.c
@@ -632,6 +632,38 @@ interface_removed(GDBusObjectManager *object_manager,
 }
 
 static void
+object_added(GDBusObjectManager *object_manager, GDBusObject *object, gpointer user_data)
+{
+    GList *interfaces, *iter;
+
+    interfaces = g_dbus_object_get_interfaces(object);
+
+    for (iter = interfaces; iter; iter = iter->next) {
+        GDBusInterface *interface = G_DBUS_INTERFACE(iter->data);
+
+        interface_added(NULL, object, interface, user_data);
+    }
+
+    g_list_free_full(interfaces, g_object_unref);
+}
+
+static void
+object_removed(GDBusObjectManager *object_manager, GDBusObject *object, gpointer user_data)
+{
+    GList *interfaces, *iter;
+
+    interfaces = g_dbus_object_get_interfaces(object);
+
+    for (iter = interfaces; iter; iter = iter->next) {
+        GDBusInterface *interface = G_DBUS_INTERFACE(iter->data);
+
+        interface_removed(NULL, object, interface, user_data);
+    }
+
+    g_list_free_full(interfaces, g_object_unref);
+}
+
+static void
 connection_removed(NMSettings *settings, NMSettingsConnection *sett_conn, gpointer user_data)
 {
     NMIwdManager *       self = user_data;
@@ -697,22 +729,6 @@ _om_has_name_owner(GDBusObjectManager *object_manager)
 }
 
 static void
-object_added(NMIwdManager *self, GDBusObject *object)
-{
-    GList *interfaces, *iter;
-
-    interfaces = g_dbus_object_get_interfaces(object);
-
-    for (iter = interfaces; iter; iter = iter->next) {
-        GDBusInterface *interface = G_DBUS_INTERFACE(iter->data);
-
-        interface_added(NULL, object, interface, self);
-    }
-
-    g_list_free_full(interfaces, g_object_unref);
-}
-
-static void
 release_object_manager(NMIwdManager *self)
 {
     NMIwdManagerPrivate *priv = NM_IWD_MANAGER_GET_PRIVATE(self);
@@ -852,12 +868,14 @@ got_object_manager(GObject *object, GAsyncResult *result, gpointer user_data)
                          "interface-removed",
                          G_CALLBACK(interface_removed),
                          self);
+        g_signal_connect(priv->object_manager, "object-added", G_CALLBACK(object_added), self);
+        g_signal_connect(priv->object_manager, "object-removed", G_CALLBACK(object_removed), self);
 
         g_hash_table_remove_all(priv->known_networks);
 
         objects = g_dbus_object_manager_get_objects(object_manager);
         for (iter = objects; iter; iter = iter->next)
-            object_added(self, G_DBUS_OBJECT(iter->data));
+            object_added(NULL, G_DBUS_OBJECT(iter->data), self);
 
         g_list_free_full(objects, g_object_unref);