[LOG4J2-295] BufferOverflowException in FastFileManager when logging huge messages

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Affects Version/s: 2.0-beta7
• Fix Version/s: 2.0-beta8
• Component/s: Appenders
• Assignee: Remko Popma
• Reporter: Tom Wieczorek
• Created: 28/Jun/13 07:16
• Updated: 04/Jul/13 14:18
• Resolved: 30/Jun/13 00:42

Description

When logging messages larger than FastFileManager.DEFAULT_BUFFER_SIZE with appenders using FastFileManager, the logging fails internally with a BufferOverflowException and no log output is produced by these appenders.

---

Test case

import java.util.Arrays;

import org.apache.logging.log4j.LogManager;

public class TestBufferOverflow {

  public static void main(String[] args) {

    final String longMessage;
    {
      char[] chars = new char[384 * 1024];
      Arrays.fill(chars, 'x');
      longMessage = new String(chars);
    }

    LogManager.getLogger("TestBufferOverflow").info(longMessage);
  }
}

---

log4j2.xml

<?xml version="1.0" encoding="UTF-8"?>
<configuration>
  <appenders>
    <FastFile name="file" fileName="test.log" suppressExceptions="false">
      <PatternLayout>
        <pattern>%m%n</pattern>
      </PatternLayout>
    </FastFile>
  </appenders>
  <loggers>
    <root level="info">
      <appender-ref ref="file" />
    </root>
  </loggers>
</configuration>

---

Exception thrown

Exception in thread "main" org.apache.logging.log4j.core.appender.AppenderRuntimeException: An exception occurred processing Appender file
	at org.apache.logging.log4j.core.appender.DefaultErrorHandler.error(DefaultErrorHandler.java:73)
	at org.apache.logging.log4j.core.config.AppenderControl.callAppender(AppenderControl.java:104)
	at org.apache.logging.log4j.core.config.LoggerConfig.callAppenders(LoggerConfig.java:424)
	at org.apache.logging.log4j.core.config.LoggerConfig.log(LoggerConfig.java:405)
	at org.apache.logging.log4j.core.config.LoggerConfig.log(LoggerConfig.java:366)
	at org.apache.logging.log4j.core.Logger.log(Logger.java:110)
	at org.apache.logging.log4j.spi.AbstractLogger.info(AbstractLogger.java:1010)
	at TestBufferOverflow.main(TestBufferOverflow.java:16)
Caused by: java.nio.BufferOverflowException
	at java.nio.HeapByteBuffer.put(HeapByteBuffer.java:165)
	at org.apache.logging.log4j.core.appender.FastFileManager.write(FastFileManager.java:89)
	at org.apache.logging.log4j.core.appender.OutputStreamManager.write(OutputStreamManager.java:129)
	at org.apache.logging.log4j.core.appender.AbstractOutputStreamAppender.append(AbstractOutputStreamAppender.java:113)
	at org.apache.logging.log4j.core.appender.FastFileAppender.append(FastFileAppender.java:84)
	at org.apache.logging.log4j.core.config.AppenderControl.callAppender(AppenderControl.java:102)
	... 6 more