Merge "channel.c: Fix unbalanced read queue deadlocking local channels." into 13

main/channel.c

@@ -1147,6 +1147,9 @@ static int __ast_queue_frame(struct ast_channel *chan, struct ast_frame *fin, in
 				}
 				AST_LIST_REMOVE_CURRENT(frame_list);
 				ast_frfree(cur);
+
+				/* Read from the alert pipe for each flushed frame. */
+				ast_channel_internal_alert_read(chan);
 			}
 		}
 		AST_LIST_TRAVERSE_SAFE_END;
@@ -1163,9 +1166,13 @@ static int __ast_queue_frame(struct ast_channel *chan, struct ast_frame *fin, in
 	}
 
 	if (ast_channel_alert_writable(chan)) {
+		/* Write to the alert pipe for each added frame */
+		while (new_frames--) {
 			if (ast_channel_alert_write(chan)) {
 				ast_log(LOG_WARNING, "Unable to write to alert pipe on %s (qlen = %u): %s!\n",
 					ast_channel_name(chan), queued_frames, strerror(errno));
+				break;
+			}
 		}
 	} else if (ast_channel_timingfd(chan) > -1) {
 		ast_timer_enable_continuous(ast_channel_timer(chan));