Fix race in agent/masquerade

git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@1196 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channel.c

@@ -1811,6 +1811,7 @@ int ast_channel_masquerade(struct ast_channel *original, struct ast_channel *clo
 	   not really safe not to XXX */
 	ast_queue_frame(original, &null, 0);
 	ast_queue_frame(clone, &null, 0);
+	ast_log(LOG_DEBUG, "Done planning to masquerade %s into the structure of %s\n", original->name, clone->name);
 	return 0;
 }
 

channels/chan_agent.c

@@ -634,8 +634,10 @@ static int check_availability(struct agent_pvt *newlyavailable, int needlock)
 				ast_setstate(chan, AST_STATE_UP);
 				/* Go ahead and mark the channel as a zombie so that masquerade will
 				   destroy it for us, and we need not call ast_hangup */
+				ast_pthread_mutex_lock(&parent->lock);
 				chan->zombie = 1;
 				ast_channel_masquerade(parent, chan);
+				ast_pthread_mutex_unlock(&parent->lock);
 				p->abouttograb = 0;
 			} else {
 				ast_log(LOG_DEBUG, "Sneaky, parent disappeared in the mean time...\n");