Fix bridge/channel AMI event ordering issues

The stasis_cache_update messages are somewhat cumbersome to handle
with the stasis_message_router. Since all updates have the same
message type, they are normally handled with the same route.

Since caching itself is a first class component of stasis-core, it
makes sense for the router to handle the cache update messages itself.
This patch adds stasis_message_router_add_cache_update() and
stasis_message_router_remove_cache_update() to handle the routing of
stasis_cache_update messages.

This patch also corrects an issue with manager_{bridging,channels}.c,
where events might be reordered. The reordering occurs because the
components use different message routers, which they needed because
they both needed to route cache update messages. They now both use
manager's router, and add cache routes for just the cache updates they
are interested in.

(closes issue ASTERISK-22038)
Review: https://reviewboard.asterisk.org/r/2677/


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@395118 65c4cc65-6c06-0410-ace0-fbb531ad65f3

1 files changed, 41 insertions, 4 deletions

diff --git a/include/asterisk/stasis_message_router.h b/include/asterisk/stasis_message_router.h
index 81a636dcd..b14868b4a 100644
--- a/include/asterisk/stasis_message_router.h
+++ b/include/asterisk/stasis_message_router.h
@@ -95,6 +95,11 @@ int stasis_message_router_is_done(struct stasis_message_router *router);
 /*!
  * \brief Add a route to a message router.
  *
+ * A particular \a message_type may have at most one route per \a router. If
+ * you route \ref stasis_cache_update messages, the callback will only receive
+ * updates for types not handled by routes added with
+ * stasis_message_router_add_cache_update().
+ *
  * \param router Router to add the route to.
  * \param message_type Type of message to route.
  * \param callback Callback to forard messages of \a message_type to.
@@ -106,9 +111,29 @@ int stasis_message_router_is_done(struct stasis_message_router *router);
  * \since 12
  */
 int stasis_message_router_add(struct stasis_message_router *router,
-			      struct stasis_message_type *message_type,
-			      stasis_subscription_cb callback,
-			      void *data);
+	struct stasis_message_type *message_type,
+	stasis_subscription_cb callback, void *data);
+
+/*!
+ * \brief Add a route for \ref stasis_cache_update messages to a message router.
+ *
+ * A particular \a message_type may have at most one cache route per \a router.
+ * These are distinct from regular routes, so one could have both a regular
+ * route and a cache route for the same \a message_type.
+ *
+ * \param router Router to add the route to.
+ * \param message_type Subtype of cache update to route.
+ * \param callback Callback to forard messages of \a message_type to.
+ * \param data Data pointer to pass to \a callback.
+ *
+ * \retval 0 on success
+ * \retval -1 on failure
+ *
+ * \since 12
+ */
+int stasis_message_router_add_cache_update(struct stasis_message_router *router,
+	struct stasis_message_type *message_type,
+	stasis_subscription_cb callback, void *data);
 
 /*!
  * \brief Remove a route from a message router.
@@ -119,7 +144,19 @@ int stasis_message_router_add(struct stasis_message_router *router,
  * \since 12
  */
 void stasis_message_router_remove(struct stasis_message_router *router,
-			      struct stasis_message_type *message_type);
+	struct stasis_message_type *message_type);
+
+/*!
+ * \brief Remove a cache route from a message router.
+ *
+ * \param router Router to remove the route from.
+ * \param message_type Type of message to route.
+ *
+ * \since 12
+ */
+void stasis_message_router_remove_cache_update(
+	struct stasis_message_router *router,
+	struct stasis_message_type *message_type);
 
 /*!
  * \brief Sets the default route of a router.