ensure that channel cannot become zombie after we check but before we try to start indications

git-svn-id: https://origsvn.digium.com/svn/asterisk/branches/1.2@8588 65c4cc65-6c06-0410-ace0-fbb531ad65f3

channel.c

@@ -2005,10 +2005,12 @@ int ast_indicate(struct ast_channel *chan, int condition)
 {
 	int res = -1;
 
+	ast_mutex_lock(&chan->lock);
 	/* Stop if we're a zombie or need a soft hangup */
-	if (ast_test_flag(chan, AST_FLAG_ZOMBIE) || ast_check_hangup(chan)) 
+	if (ast_test_flag(chan, AST_FLAG_ZOMBIE) || ast_check_hangup(chan)) {
+		ast_mutex_unlock(&chan->lock);
 		return -1;
-	ast_mutex_lock(&chan->lock);
+	}
 	if (chan->tech->indicate)
 		res = chan->tech->indicate(chan, condition);
 	ast_mutex_unlock(&chan->lock);