From: Matthew Nicholson <mnicholson@digium.com>
Date: Mon, 12 Sep 2011 15:49:24 +0000 (+0000)
Subject: Prevent a race condition when the bridge technology changes. This change was
X-Git-Tag: 1.8.8.0-rc1~78
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=828a733f587f64c2a1c92125c572754e14457f63;p=thirdparty%2Fasterisk.git

Prevent a race condition when the bridge technology changes. This change was
ported from asterisk 10.

ASTERISK-18155


git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.8@335431 65c4cc65-6c06-0410-ace0-fbb531ad65f3
---

diff --git a/bridges/bridge_multiplexed.c b/bridges/bridge_multiplexed.c
index e97e154608..b6d376fc5a 100644
--- a/bridges/bridge_multiplexed.c
+++ b/bridges/bridge_multiplexed.c
@@ -223,6 +223,9 @@ static void *multiplexed_thread_function(void *data)
 		winner = ast_waitfor_nandfds(multiplexed_thread->chans, multiplexed_thread->service_count, &fds, 1, NULL, &outfd, &to);
 		multiplexed_thread->waiting = 0;
 		ao2_lock(multiplexed_thread);
+		if (multiplexed_thread->thread == AST_PTHREADT_STOP) {
+			break;
+		}
 
 		if (outfd > -1) {
 			int nudge;
@@ -234,7 +237,21 @@ static void *multiplexed_thread_function(void *data)
 			}
 		}
 		if (winner && winner->bridge) {
-			ast_bridge_handle_trip(winner->bridge, NULL, winner, -1);
+			struct ast_bridge *bridge = winner->bridge;
+			int stop = 0;
+			ao2_unlock(multiplexed_thread);
+			while ((bridge = winner->bridge) && ao2_trylock(bridge)) {
+				sched_yield();
+				if (multiplexed_thread->thread == AST_PTHREADT_STOP) {
+					stop = 1;
+					break;
+				}
+			}
+			if (!stop && bridge) {
+				ast_bridge_handle_trip(bridge, NULL, winner, -1);
+				ao2_unlock(bridge);
+			}
+			ao2_lock(multiplexed_thread);
 		}
 	}