nm-object: delay object property completion until the objects are initialized

We don't want to update the properties until the objects referred are complete.
Otherwise the clients get confused. Very confused:

https://bugzilla.redhat.com/show_bug.cgi?id=1313866

We already delay the notification signals. Let's replace that with delaying the
actual ObjectCreatedData processing instead.

diff --git a/libnm/nm-object.c b/libnm/nm-object.c
index 536be54..3b41041 100644 (file)
--- a/libnm/nm-object.c
+++ b/libnm/nm-object.c
@@ -205,24 +205,6 @@ deferred_notify_cb (gpointer data)
        if (priv->reload_remaining)
                return G_SOURCE_REMOVE;
 
-       /* If not all added object are finished yet, then defer the deferred
-        * notification. */
-       for (iter = priv->notify_items; iter; iter = g_slist_next (iter)) {
-               NotifyItem *item = iter->data;
-               NMObjectPrivate *item_priv;
-
-               if (!item->changed)
-                       continue;
-
-               item_priv = NM_OBJECT_GET_PRIVATE (item->changed);
-               if (!item_priv->inited) {
-                       if (!g_slist_find (item_priv->waiters, object))
-                               item_priv->waiters = g_slist_prepend (item_priv->waiters,
-                                                                     g_object_ref (object));
-                       return G_SOURCE_REMOVE;
-               }
-       }
-
        /* Clear priv->notify_items early so that an NMObject subclass that
         * listens to property changes can queue up other property changes
         * during the g_object_notify() call separately from the property
@@ -458,6 +440,32 @@ _nm_object_create (GType type, GDBusConnection *connection, const char *path)
        return object;
 }
 
+typedef struct {
+       NMObject *self;
+       PropertyInfo *pi;
+
+       GObject **objects;
+       int length, remaining;
+
+       GPtrArray *array;
+       const char *property_name;
+} ObjectCreatedData;
+
+static void
+odata_free (gpointer data)
+{
+       ObjectCreatedData *odata = data;
+
+       g_object_unref (odata->self);
+       g_free (odata->objects);
+       if (odata->array)
+               g_ptr_array_unref (odata->array);
+       g_slice_free (ObjectCreatedData, odata);
+}
+
+static void object_property_maybe_complete (ObjectCreatedData *odata);
+
+
 typedef void (*NMObjectCreateCallbackFunc) (GObject *, const char *, gpointer);
 typedef struct {
        char *path;
@@ -497,13 +505,13 @@ create_async_inited (GObject *object, GAsyncResult *result, gpointer user_data)
        if (object) {
                NMObjectPrivate *priv = NM_OBJECT_GET_PRIVATE (object);
 
-               /* Re-queue notification checks for whoever was waiting for
-                * this object to initialize. */
+               /* There are some object properties whose creation couldn't proceed
+                * because it depended on this object. */
                while (priv->waiters) {
-                       NMObject *item = priv->waiters->data;
-                       priv->waiters = g_slist_remove (priv->waiters, item);
-                       _nm_object_defer_notify (item);
-                       g_object_unref (item);
+                       ObjectCreatedData *odata = priv->waiters->data;
+
+                       priv->waiters = g_slist_remove (priv->waiters, odata);
+                       object_property_maybe_complete (odata);
                }
        }
 }
@@ -656,17 +664,6 @@ add_to_object_array_unique (GPtrArray *array, GObject *obj)
        }
 }
 
-typedef struct {
-       NMObject *self;
-       PropertyInfo *pi;
-
-       GObject **objects;
-       int length, remaining;
-
-       GPtrArray *array;
-       const char *property_name;
-} ObjectCreatedData;
-
 /* Places items from 'needles' that are not in 'haystack' into 'diff' */
 static void
 array_diff (GPtrArray *needles, GPtrArray *haystack, GPtrArray *diff)
@@ -700,19 +697,59 @@ queue_added_removed_signal (NMObject *self,
        _nm_object_queue_notify_full (self, NULL, signal_prefix, added, changed);
 }
 
+static gboolean
+already_awaits (ObjectCreatedData *odata, GObject *object)
+{
+       NMObject *self = odata->self;
+       NMObjectPrivate *priv = NM_OBJECT_GET_PRIVATE (self);
+       GSList *iter;
+
+       if ((GObject *)odata->self == object)
+               return TRUE;
+
+       for (iter = priv->waiters; iter; iter = g_slist_next (iter)) {
+               if (already_awaits (iter->data, object))
+                       return TRUE;
+       }
+
+       return FALSE;
+}
+
 static void
-object_property_complete (ObjectCreatedData *odata)
+object_property_maybe_complete (ObjectCreatedData *odata)
 {
        NMObject *self = odata->self;
        NMObjectPrivate *priv = NM_OBJECT_GET_PRIVATE (self);
        PropertyInfo *pi = odata->pi;
        gboolean different = TRUE;
+       int i;
+
+       /* Only complete the array property load when all the objects are initialized. */
+       for (i = 0; i < odata->length; i++) {
+               GObject *obj = odata->objects[i];
+               NMObjectPrivate *obj_priv;
+
+               /* Could not load the object. Perhaps it was removed. */
+               if (!obj)
+                       continue;
+
+               obj_priv = NM_OBJECT_GET_PRIVATE (obj);
+               if (!obj_priv->inited) {
+
+                       /* The object is not finished because we block its creation. */
+                       if (already_awaits (odata, obj))
+                               continue;
+
+                       if (!g_slist_find (obj_priv->waiters, odata))
+                               obj_priv->waiters = g_slist_prepend (obj_priv->waiters, odata);
+                       return;
+               }
+       }
 
        if (odata->array) {
                GPtrArray *pi_old = *((GPtrArray **) pi->field);
                GPtrArray *old = odata->array;
                GPtrArray *new;
-               int i;
 
                /* Build up new array */
                new = g_ptr_array_new_full (odata->length, g_object_unref);
@@ -776,11 +813,7 @@ object_property_complete (ObjectCreatedData *odata)
        if (--priv->reload_remaining == 0)
                reload_complete (self, FALSE);
 
-       g_object_unref (self);
-       g_free (odata->objects);
-       if (odata->array)
-               g_ptr_array_unref (odata->array);
-       g_slice_free (ObjectCreatedData, odata);
+       odata_free (odata);
 }
 
 static void
@@ -799,7 +832,7 @@ object_created (GObject *obj, const char *path, gpointer user_data)
 
        odata->objects[--odata->remaining] = obj;
        if (!odata->remaining)
-               object_property_complete (odata);
+               object_property_maybe_complete (odata);
 }
 
 static gboolean
@@ -874,7 +907,7 @@ handle_object_array_property (NMObject *self, const char *property_name, GVarian
        priv->reload_remaining++;
 
        if (npaths == 0) {
-               object_property_complete (odata);
+               object_property_maybe_complete (odata);
                return TRUE;
        }
 
@@ -1754,7 +1787,7 @@ dispose (GObject *object)
        g_slist_free_full (priv->notify_items, (GDestroyNotify) notify_item_free);
        priv->notify_items = NULL;
 
-       g_slist_free_full (priv->waiters, g_object_unref);
+       g_slist_free_full (priv->waiters, odata_free);
        g_clear_pointer (&priv->proxies, g_hash_table_unref);
        g_clear_object (&priv->properties_proxy);