Re-order cleanup

This patch attempts to fix some possible race conditions in shutdown of the
CDR engine. It:
* Adds a cleanup handler to only unsubscribe and join on stasis messages during
  graceful shutdown. The cleanup handler should execute before the regular atexit
  handler, as we want to unsubscribe for any further messages before dispatching
  the CDRs.
* The CDRs are now locked when we dispatch them on shutdown.

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@394469 65c4cc65-6c06-0410-ace0-fbb531ad65f3

diff --git a/main/cdr.c b/main/cdr.c
index 7791440..57651ae 100644 (file)
--- a/main/cdr.c
+++ b/main/cdr.c
@@ -3854,10 +3854,12 @@ static int cdr_object_dispatch_all_cb(void *obj, void *arg, int flags)
        struct cdr_object *cdr = obj;
        struct cdr_object *it_cdr;
 
+       ao2_lock(cdr);
        for (it_cdr = cdr; it_cdr; it_cdr = it_cdr->next) {
                cdr_object_transition_state(it_cdr, &finalized_state_fn_table);
        }
        cdr_object_dispatch(cdr);
+       ao2_unlock(cdr);
 
        return 0;
 }
@@ -3919,6 +3921,14 @@ static int process_config(int reload)
        return 0;
 }
 
+static void cdr_engine_cleanup(void)
+{
+       channel_subscription = stasis_unsubscribe_and_join(channel_subscription);
+       bridge_subscription = stasis_unsubscribe_and_join(bridge_subscription);
+       parking_subscription = stasis_unsubscribe_and_join(parking_subscription);
+       stasis_message_router_unsubscribe_and_join(stasis_router);
+}
+
 static void cdr_engine_shutdown(void)
 {
        ao2_callback(active_cdrs_by_channel, OBJ_NODATA, cdr_object_dispatch_all_cb,
@@ -3930,10 +3940,6 @@ static void cdr_engine_shutdown(void)
        ast_free(batch);
        batch = NULL;
 
-       channel_subscription = stasis_unsubscribe_and_join(channel_subscription);
-       bridge_subscription = stasis_unsubscribe_and_join(bridge_subscription);
-       parking_subscription = stasis_unsubscribe_and_join(parking_subscription);
-       stasis_message_router_unsubscribe_and_join(stasis_router);
        aco_info_destroy(&cfg_info);
        ao2_global_obj_release(module_configs);
 
@@ -4035,6 +4041,7 @@ int ast_cdr_engine_init(void)
        }
 
        ast_cli_register_multiple(cli_commands, ARRAY_LEN(cli_commands));
+       ast_register_cleanup(cdr_engine_cleanup);
        ast_register_atexit(cdr_engine_shutdown);
 
        mod_cfg = ao2_global_obj_ref(module_configs);