1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one or more
3 * contributor license agreements. See the NOTICE file distributed with
4 * this work for additional information regarding copyright ownership.
5 * The ASF licenses this file to You under the Apache license, Version 2.0
6 * (the "License"); you may not use this file except in compliance with
7 * the License. You may obtain a copy of the License at
8 *
9 * http://www.apache.org/licenses/LICENSE-2.0
10 *
11 * Unless required by applicable law or agreed to in writing, software
12 * distributed under the License is distributed on an "AS IS" BASIS,
13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
14 * See the license for the specific language governing permissions and
15 * limitations under the license.
16 */
17 package org.apache.logging.log4j.core.async;
18
19 import org.apache.logging.log4j.Level;
20
21 /**
22 * Default router: enqueue the event for asynchronous logging in the background thread, unless the current thread is the
23 * background thread and the queue is full (enqueueing would cause a deadlock). In that case send the event directly to
24 * the appender (in the current thread).
25 */
26 public class DefaultAsyncQueueFullPolicy implements AsyncQueueFullPolicy {
27 @Override
28 public EventRoute getRoute(final long backgroundThreadId, final Level level) {
29
30 // LOG4J2-471: prevent deadlock when RingBuffer is full and object
31 // being logged calls Logger.log() from its toString() method
32 if (Thread.currentThread().getId() == backgroundThreadId) {
33 return EventRoute.SYNCHRONOUS;
34 }
35 return EventRoute.ENQUEUE;
36 }
37 }