/*
*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*
*/
package org.apache.cassandra.db.commitlog;
import java.io.EOFException;
import java.io.File;
import java.io.IOException;
import java.io.RandomAccessFile;
import java.nio.ByteBuffer;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import com.google.common.annotations.VisibleForTesting;
import org.apache.cassandra.io.FSReadError;
import org.apache.cassandra.net.MessagingService;
import org.apache.cassandra.utils.PureJavaCrc32;
public class CommitLogDescriptor
{
private static final String SEPARATOR = "-";
private static final String FILENAME_PREFIX = "CommitLog" + SEPARATOR;
private static final String FILENAME_EXTENSION = ".log";
// match both legacy and new version of commitlogs Ex: CommitLog-12345.log and CommitLog-4-12345.log.
private static final Pattern COMMIT_LOG_FILE_PATTERN = Pattern.compile(FILENAME_PREFIX + "((\\d+)(" + SEPARATOR + "\\d+)?)" + FILENAME_EXTENSION);
public static final int VERSION_12 = 2;
public static final int VERSION_20 = 3;
public static final int VERSION_21 = 4;
public static final int VERSION_30 = 5;
/**
* Increment this number if there is a changes in the commit log disc layout or MessagingVersion changes.
* Note: make sure to handle {@link #getMessagingVersion()}
*/
@VisibleForTesting
public static final int current_version = VERSION_30;
// [version, id, checksum]
static final int HEADER_SIZE = 4 + 8 + 4;
final int version;
public final long id;
public CommitLogDescriptor(int version, long id)
{
this.version = version;
this.id = id;
}
public CommitLogDescriptor(long id)
{
this(current_version, id);
}
static void writeHeader(ByteBuffer out, CommitLogDescriptor descriptor)
{
out.putInt(0, descriptor.version);
out.putLong(4, descriptor.id);
PureJavaCrc32 crc = new PureJavaCrc32();
crc.updateInt(descriptor.version);
crc.updateInt((int) (descriptor.id & 0xFFFFFFFFL));
crc.updateInt((int) (descriptor.id >>> 32));
out.putInt(12, crc.getCrc());
}
public static CommitLogDescriptor fromHeader(File file)
{
try (RandomAccessFile raf = new RandomAccessFile(file, "r"))
{
assert raf.getFilePointer() == 0;
int version = raf.readInt();
long id = raf.readLong();
int crc = raf.readInt();
PureJavaCrc32 checkcrc = new PureJavaCrc32();
checkcrc.updateInt(version);
checkcrc.updateInt((int) (id & 0xFFFFFFFFL));
checkcrc.updateInt((int) (id >>> 32));
if (crc == checkcrc.getCrc())
return new CommitLogDescriptor(version, id);
return null;
}
catch (EOFException e)
{
throw new RuntimeException(e);
}
catch (IOException e)
{
throw new FSReadError(e, file);
}
}
public static CommitLogDescriptor fromFileName(String name)
{
Matcher matcher;
if (!(matcher = COMMIT_LOG_FILE_PATTERN.matcher(name)).matches())
throw new RuntimeException("Cannot parse the version of the file: " + name);
if (matcher.group(3) == null)
throw new UnsupportedOperationException("Commitlog segment is too old to open; upgrade to 1.2.5+ first");
long id = Long.parseLong(matcher.group(3).split(SEPARATOR)[1]);
return new CommitLogDescriptor(Integer.parseInt(matcher.group(2)), id);
}
public int getMessagingVersion()
{
switch (version)
{
case VERSION_12:
return MessagingService.VERSION_12;
case VERSION_20:
return MessagingService.VERSION_20;
case VERSION_21:
return MessagingService.VERSION_21;
case VERSION_30:
return MessagingService.VERSION_30;
default:
throw new IllegalStateException("Unknown commitlog version " + version);
}
}
public String fileName()
{
return FILENAME_PREFIX + version + SEPARATOR + id + FILENAME_EXTENSION;
}
/**
* @param filename the filename to check
* @return true if filename could be a commit log based on it's filename
*/
public static boolean isValid(String filename)
{
return COMMIT_LOG_FILE_PATTERN.matcher(filename).matches();
}
public String toString()
{
return "(" + version + "," + id + ")";
}
public boolean equals(Object that)
{
return that instanceof CommitLogDescriptor && equals((CommitLogDescriptor) that);
}
public boolean equals(CommitLogDescriptor that)
{
return this.version == that.version && this.id == that.id;
}
}