ARI: allow other operations to happen while bridged

This patch changes ARI bridging to allow other channel operations to
happen while the channel is bridged.

ARI channel operations are designed to queue up and execute
sequentially. This meant, though, that while a channel was bridged,
any other channel operations would queue up and execute only after the
channel left the bridge.

This patch changes ARI bridging so that channel commands can execute
while the channel is bridged. For most operations, things simply work
as expected. The one thing that ended up being a bit odd is recording.

The current recording implementation will fail when one attempts to
record a channel that's in a bridge. Note that the bridge itself may
be recording; it's recording a specific channel in the bridge that
fails. While this is an annoying limitation, channel recording is
still very useful for use cases such as voice mail, and bridge
recording makes up much of the difference for other use cases.

(closes issue ASTERISK-22084)
Review: https://reviewboard.asterisk.org/r/2726/


git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@396568 65c4cc65-6c06-0410-ace0-fbb531ad65f3

include/asterisk/bridge_features.h

@@ -25,6 +25,8 @@
 #ifndef _ASTERISK_BRIDGING_FEATURES_H
 #define _ASTERISK_BRIDGING_FEATURES_H
 
+#include "asterisk/channel.h"
+
 #if defined(__cplusplus) || defined(c_plusplus)
 extern "C" {
 #endif

include/asterisk/bridge_internal.h

@@ -36,6 +36,7 @@
 
 struct ast_bridge;
 struct ast_bridge_channel;
+struct ast_bridge_methods;
 
 /*!
  * \brief Register the new bridge with the system.

include/asterisk/stasis_app.h

@@ -348,11 +348,8 @@ void stasis_app_control_add_channel_to_bridge(
  *
  * \param control Control whose channel should be removed from the bridge
  * \param bridge Pointer to the bridge
- *
- * \retval non-zero on failure
- * \retval zero on success
  */
-int stasis_app_control_remove_channel_from_bridge(
+void stasis_app_control_remove_channel_from_bridge(
 	struct stasis_app_control *control, struct ast_bridge *bridge);
 
 /*!

include/asterisk/stasis_app_impl.h

@@ -85,4 +85,14 @@ void *stasis_app_send_command(struct stasis_app_control *control,
 int stasis_app_send_command_async(struct stasis_app_control *control,
 	stasis_app_command_cb command, void *data);
 
+/*!
+ * \since 12
+ * \brief Gets the bridge currently associated with a control object.
+ *
+ * \param control Control object for the channel to query.
+ * \return Associated \ref ast_bridge.
+ * \return \c NULL if not associated with a bridge.
+ */
+struct ast_bridge *stasis_app_get_bridge(struct stasis_app_control *control);
+
 #endif /* _ASTERISK_RES_STASIS_H */