protect agent_bridgedchannel() from segfaulting when there is no bridged channel (issue #5879)

git-svn-id: http://svn.digium.com/svn/asterisk/branches/1.2@7271 f38db490-d61c-443f-a65b-d21fe96a405b

1 files changed, 8 insertions, 7 deletions

diff --git a/channels/chan_agent.c b/channels/chan_agent.c
index e2ef0f203..a754f8a8f 100644
--- a/channels/chan_agent.c
+++ b/channels/chan_agent.c
@@ -910,15 +910,16 @@ static int agent_ack_sleep( void *data )
 
 static struct ast_channel *agent_bridgedchannel(struct ast_channel *chan, struct ast_channel *bridge)
 {
-	struct agent_pvt *p;
+	struct agent_pvt *p = bridge->tech_pvt;
 	struct ast_channel *ret=NULL;
-	
 
-	p = bridge->tech_pvt;
-	if (chan == p->chan)
-		ret = bridge->_bridge;
-	else if (chan == bridge->_bridge)
-		ret = p->chan;
+	if (p) {
+		if (chan == p->chan)
+			ret = bridge->_bridge;
+		else if (chan == bridge->_bridge)
+			ret = p->chan;
+	}
+
 	if (option_debug)
 		ast_log(LOG_DEBUG, "Asked for bridged channel on '%s'/'%s', returning '%s'\n", chan->name, bridge->name, ret ? ret->name : "<none>");
 	return ret;