Fix ao2_iterator API to hold references to containers being iterated.

See Mantis issue for details of what prompted this change.

Additional notes:

This patch changes the ao2_iterator API in two ways: F_AO2I_DONTLOCK
has become an enum instead of a macro, with a name that fits our
naming policy; also, it is now necessary to call
ao2_iterator_destroy() on any iterator that has been
created. Currently this only releases the reference to the container
being iterated, but in the future this could also release other
resources used by the iterator, if the iterator implementation changes
to use additional resources.

(closes issue #15987)
Reported by: kpfleming

Review: https://reviewboard.asterisk.org/r/383/


git-svn-id: http://svn.digium.com/svn/asterisk/branches/1.4@222152 f38db490-d61c-443f-a65b-d21fe96a405b

1 files changed, 29 insertions, 2 deletions

diff --git a/apps/app_queue.c b/apps/app_queue.c
index cfcc9fb05..a94538228 100644
--- a/apps/app_queue.c
+++ b/apps/app_queue.c
@@ -578,7 +578,7 @@ static enum queue_member_status get_member_status(struct call_queue *q, int max_
 			return QUEUE_NORMAL;
 		}
 	}
-
+	ao2_iterator_destroy(&mem_iter);
 	ast_mutex_unlock(&q->lock);
 	return result;
 }
@@ -634,6 +634,7 @@ static int update_status(const char *interface, const int status)
 			}
 			ao2_ref(cur, -1);
 		}
+		ao2_iterator_destroy(&mem_iter);
 		ast_mutex_unlock(&q->lock);
 	}
 	AST_LIST_UNLOCK(&queues);
@@ -924,6 +925,7 @@ static int interface_exists_global(const char *interface)
 			}
 			ao2_ref(mem, -1);
 		}
+		ao2_iterator_destroy(&mem_iter);
 		ast_mutex_unlock(&q->lock);
 		if (ret)
 			break;
@@ -1182,6 +1184,7 @@ static void free_members(struct call_queue *q, int all)
 		}
 		ao2_ref(cur, -1);
 	}
+	ao2_iterator_destroy(&mem_iter);
 }
 
 static void destroy_queue(struct call_queue *q)
@@ -1291,6 +1294,7 @@ static struct call_queue *find_queue_by_name_rt(const char *queuename, struct as
 			m->dead = 1;
 		ao2_ref(m, -1);
 	}
+	ao2_iterator_destroy(&mem_iter);
 
 	while ((interface = ast_category_browse(member_config, interface))) {
 		rt_handle_member_record(q, interface,
@@ -1312,6 +1316,7 @@ static struct call_queue *find_queue_by_name_rt(const char *queuename, struct as
 		}
 		ao2_ref(m, -1);
 	}
+	ao2_iterator_destroy(&mem_iter);
 
 	ast_mutex_unlock(&q->lock);
 
@@ -1362,6 +1367,7 @@ static void update_realtime_members(struct call_queue *q)
 			m->dead = 1;
 		ao2_ref(m, -1);
 	}
+	ao2_iterator_destroy(&mem_iter);
 
 	while ((interface = ast_category_browse(member_config, interface))) {
 		rt_handle_member_record(q, interface,
@@ -1383,6 +1389,7 @@ static void update_realtime_members(struct call_queue *q)
 		}
 		ao2_ref(m, -1);
 	}
+	ao2_iterator_destroy(&mem_iter);
 	ast_mutex_unlock(&q->lock);
 	ast_config_destroy(member_config);
 }
@@ -1782,6 +1789,7 @@ static int num_available_members(struct call_queue *q)
 			break;
 		}
 	}
+	ao2_iterator_destroy(&mem_iter);
 
 	return avl;
 }
@@ -2873,6 +2881,7 @@ static int try_calling(struct queue_ent *qe, const char *options, char *announce
 		struct ast_dialed_interface *di;
 		AST_LIST_HEAD(, ast_dialed_interface) *dialed_interfaces;
 		if (!tmp) {
+			ao2_iterator_destroy(&memi);
 			ao2_ref(cur, -1);
 			ast_mutex_unlock(&qe->parent->lock);
 			if (use_weight)
@@ -2881,6 +2890,7 @@ static int try_calling(struct queue_ent *qe, const char *options, char *announce
 		}
 		if (!datastore) {
 			if (!(datastore = ast_channel_datastore_alloc(&dialed_interface_info, NULL))) {
+				ao2_iterator_destroy(&memi);
 				ao2_ref(cur, -1);
 				ast_mutex_unlock(&qe->parent->lock);
 				if (use_weight)
@@ -2890,6 +2900,7 @@ static int try_calling(struct queue_ent *qe, const char *options, char *announce
 			}
 			datastore->inheritance = DATASTORE_INHERIT_FOREVER;
 			if (!(dialed_interfaces = ast_calloc(1, sizeof(*dialed_interfaces)))) {
+				ao2_iterator_destroy(&memi);
 				ao2_ref(cur, -1);
 				ast_mutex_unlock(&qe->parent->lock);
 				if (use_weight)
@@ -2927,6 +2938,7 @@ static int try_calling(struct queue_ent *qe, const char *options, char *announce
 		 * it won't call one that has already been called. */
 		if (strncasecmp(cur->interface, "Local/", 6)) {
 			if (!(di = ast_calloc(1, sizeof(*di) + strlen(cur->interface)))) {
+				ao2_iterator_destroy(&memi);
 				ao2_ref(cur, -1);
 				ast_mutex_unlock(&qe->parent->lock);
 				if (use_weight)
@@ -2962,6 +2974,7 @@ static int try_calling(struct queue_ent *qe, const char *options, char *announce
 			free(tmp);
 		}
 	}
+	ao2_iterator_destroy(&memi);
 	if (qe->expire && (!qe->parent->timeout || (qe->expire - now) <= qe->parent->timeout))
 		to = (qe->expire - now) * 1000;
 	else
@@ -3330,10 +3343,13 @@ static struct member *interface_exists(struct call_queue *q, const char *interfa
 
 	mem_iter = ao2_iterator_init(q->members, 0);
 	while ((mem = ao2_iterator_next(&mem_iter))) {
-		if (!strcasecmp(interface, mem->interface))
+		if (!strcasecmp(interface, mem->interface)) {
+			ao2_iterator_destroy(&mem_iter);
 			return mem;
+		}
 		ao2_ref(mem, -1);
 	}
+	ao2_iterator_destroy(&mem_iter);
 
 	return NULL;
 }
@@ -3375,6 +3391,7 @@ static void dump_queue_members(struct call_queue *pm_queue)
 		}
 		value_len += res;
 	}
+	ao2_iterator_destroy(&mem_iter);
 	
 	if (value_len && !cur_member) {
 		if (ast_db_put(pm_family, pm_queue->name, value))
@@ -4228,6 +4245,7 @@ static int queue_function_qac(struct ast_channel *chan, char *cmd, char *data, c
 			}
 			ao2_ref(m, -1);
 		}
+		ao2_iterator_destroy(&mem_iter);
 		ast_mutex_unlock(&q->lock);
 	} else
 		ast_log(LOG_WARNING, "queue %s was not found\n", data);
@@ -4326,6 +4344,7 @@ static int queue_function_queuememberlist(struct ast_channel *chan, char *cmd, c
 			}
 			ao2_ref(m, -1);
 		}
+		ao2_iterator_destroy(&mem_iter);
 		ast_mutex_unlock(&q->lock);
 	} else
 		ast_log(LOG_WARNING, "queue %s was not found\n", data);
@@ -4458,6 +4477,7 @@ static int reload_queues(void)
 					}
 					ao2_ref(cur, -1);
 				}
+				ao2_iterator_destroy(&mem_iter);
 				for (var = ast_variable_browse(cfg, cat); var; var = var->next) {
 					if (!strcasecmp(var->name, "member")) {
 						struct member tmpmem;
@@ -4536,6 +4556,7 @@ static int reload_queues(void)
 					remove_from_interfaces(cur->state_interface);
 					ao2_ref(cur, -1);
 				}
+				ao2_iterator_destroy(&mem_iter);
 
 				if (q->strategy == QUEUE_STRATEGY_ROUNDROBIN)
 					rr_dep_warning();
@@ -4564,6 +4585,7 @@ static int reload_queues(void)
 				cur->status = ast_device_state(cur->state_interface);
 				ao2_ref(cur, -1);
 			}
+			ao2_iterator_destroy(&mem_iter);
 			ast_mutex_unlock(&q->lock);
 		}
 	}
@@ -4686,6 +4708,7 @@ static int __queues_show(struct mansession *s, int manager, int fd, int argc, ch
 					ast_cli(fd, "      %s%s%s", mem->membername, max_buf, term);
 				ao2_ref(mem, -1);
 			}
+			ao2_iterator_destroy(&mem_iter);
 		} else if (s)
 			astman_append(s, "   No Members%s", term);
 		else	
@@ -4828,6 +4851,7 @@ static int manager_queues_status(struct mansession *s, const struct message *m)
 				}
 				ao2_ref(mem, -1);
 			}
+			ao2_iterator_destroy(&mem_iter);
 			/* List Queue Entries */
 			pos = 1;
 			for (qe = q->head; qe; qe = qe->next) {
@@ -4845,6 +4869,7 @@ static int manager_queues_status(struct mansession *s, const struct message *m)
 					S_OR(qe->chan->cid.cid_name, "unknown"),
 					(long) (now - qe->start), idText);
 			}
+			ao2_iterator_destroy(&mem_iter);
 		}
 		ast_mutex_unlock(&q->lock);
 	}
@@ -5120,6 +5145,7 @@ static char *complete_queue_remove_member(const char *line, const char *word, in
 			while ((m = ao2_iterator_next(&mem_iter))) {
 				if (++which > state) {
 					char *tmp;
+					ao2_iterator_destroy(&mem_iter);
 					ast_mutex_unlock(&q->lock);
 					tmp = ast_strdup(m->interface);
 					ao2_ref(m, -1);
@@ -5127,6 +5153,7 @@ static char *complete_queue_remove_member(const char *line, const char *word, in
 				}
 				ao2_ref(m, -1);
 			}
+			ao2_iterator_destroy(&mem_iter);
 			ast_mutex_unlock(&q->lock);
 		}
 	}