+ GNUNET_assert (GNUNET_MESSAGE_TYPE_SET_REMOVE == ntohs (m->type));
+
+ msg = (const struct GNUNET_SET_ElementMessage *) m;
+ el.size = ntohs (m->size) - sizeof *msg;
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Client removes element of size %u\n",
+ el.size);
+ el.data = &msg[1];
+ el.element_type = ntohs (msg->element_type);
+ GNUNET_SET_element_hash (&el, &hash);
+ ee = GNUNET_CONTAINER_multihashmap_get (set->content->elements,
+ &hash);
+ if (NULL == ee)
+ {
+ /* Client tried to remove non-existing element. */
+ return;
+ }
+ if (GNUNET_NO == _GSS_is_element_of_set (ee, set))
+ {
+ /* Client tried to remove element twice */
+ return;
+ }
+ else
+ {
+ struct MutationEvent mut = {
+ .generation = set->current_generation,
+ .added = GNUNET_NO
+ };
+ GNUNET_array_append (ee->mutations, ee->mutations_size, mut);
+ }
+ set->vt->remove (set->state, ee);
+}
+
+
+
+static void
+execute_mutation (struct Set *set,
+ const struct GNUNET_MessageHeader *m)
+{
+ switch (ntohs (m->type))
+ {
+ case GNUNET_MESSAGE_TYPE_SET_ADD:
+ execute_add (set, m);
+ break;
+ case GNUNET_MESSAGE_TYPE_SET_REMOVE:
+ execute_remove (set, m);
+ break;
+ default:
+ GNUNET_break (0);
+ }
+}
+
+
+
+/**
+ * Send the next element of a set to the set's client. The next element is given by
+ * the set's current hashmap iterator. The set's iterator will be set to NULL if there
+ * are no more elements in the set. The caller must ensure that the set's iterator is
+ * valid.
+ *
+ * The client will acknowledge each received element with a
+ * #GNUNET_MESSAGE_TYPE_SET_ITER_ACK message. Our
+ * #handle_client_iter_ack() will then trigger the next transmission.
+ * Note that the #GNUNET_MESSAGE_TYPE_SET_ITER_DONE is not acknowledged.
+ *
+ * @param set set that should send its next element to its client
+ */
+static void
+send_client_element (struct Set *set)
+{
+ int ret;
+ struct ElementEntry *ee;
+ struct GNUNET_MQ_Envelope *ev;
+ struct GNUNET_SET_IterResponseMessage *msg;
+
+ GNUNET_assert (NULL != set->iter);
+
+again:
+
+ ret = GNUNET_CONTAINER_multihashmap_iterator_next (set->iter,
+ NULL,
+ (const void **) &ee);
+ if (GNUNET_NO == ret)
+ {
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Iteration on %p done.\n",
+ (void *) set);
+ ev = GNUNET_MQ_msg_header (GNUNET_MESSAGE_TYPE_SET_ITER_DONE);
+ GNUNET_CONTAINER_multihashmap_iterator_destroy (set->iter);
+ set->iter = NULL;
+ set->iteration_id++;
+
+ GNUNET_assert (set->content->iterator_count > 0);
+ set->content->iterator_count -= 1;
+
+ if (0 == set->content->iterator_count)
+ {
+ while (NULL != set->content->pending_mutations_head)
+ {
+ struct PendingMutation *pm;
+
+ pm = set->content->pending_mutations_head;
+ GNUNET_CONTAINER_DLL_remove (set->content->pending_mutations_head,
+ set->content->pending_mutations_tail,
+ pm);
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Executing pending mutation on %p.\n",
+ (void *) pm->set);
+ execute_mutation (pm->set, pm->mutation_message);
+ GNUNET_free (pm->mutation_message);
+ GNUNET_free (pm);
+ }
+ }
+
+ }
+ else
+ {
+ GNUNET_assert (NULL != ee);
+
+ if (GNUNET_NO == is_element_of_iteration (ee, set))
+ goto again;
+
+ GNUNET_log (GNUNET_ERROR_TYPE_DEBUG,
+ "Sending iteration element on %p.\n",
+ (void *) set);
+ ev = GNUNET_MQ_msg_extra (msg,
+ ee->element.size,
+ GNUNET_MESSAGE_TYPE_SET_ITER_ELEMENT);
+ GNUNET_memcpy (&msg[1],
+ ee->element.data,
+ ee->element.size);
+ msg->element_type = htons (ee->element.element_type);
+ msg->iteration_id = htons (set->iteration_id);
+ }
+ GNUNET_MQ_send (set->client_mq, ev);
+}
+
+
+/**
+ * Called when a client wants to iterate the elements of a set.
+ * Checks if we have a set associated with the client and if we
+ * can right now start an iteration. If all checks out, starts
+ * sending the elements of the set to the client.
+ *
+ * @param cls unused
+ * @param client client that sent the message
+ * @param m message sent by the client
+ */
+static void
+handle_client_iterate (void *cls,
+ struct GNUNET_SERVER_Client *client,
+ const struct GNUNET_MessageHeader *m)
+{
+ struct Set *set;
+
+ set = set_get (client);
+ if (NULL == set)