/*
* 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.jackrabbit.mk.blobs;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.security.DigestInputStream;
import java.security.MessageDigest;
import org.apache.jackrabbit.mk.util.ExceptionFactory;
import org.apache.jackrabbit.mk.util.IOUtils;
import org.apache.jackrabbit.mk.util.StringUtils;
/**
* A file blob store.
*/
public class FileBlobStore extends AbstractBlobStore {
private static final String OLD_SUFFIX = "_old";
private final File baseDir;
private final byte[] buffer = new byte[16 * 1024];
private boolean mark;
public FileBlobStore(String dir) throws IOException {
baseDir = new File(dir);
baseDir.mkdirs();
}
@Override
public String addBlob(String tempFilePath) {
try {
File file = new File(tempFilePath);
InputStream in = new FileInputStream(file);
MessageDigest messageDigest = MessageDigest.getInstance(HASH_ALGORITHM);
DigestInputStream din = new DigestInputStream(in, messageDigest);
long length = file.length();
try {
while (true) {
int len = din.read(buffer, 0, buffer.length);
if (len < 0) {
break;
}
}
} finally {
din.close();
}
ByteArrayOutputStream idStream = new ByteArrayOutputStream();
idStream.write(TYPE_HASH);
IOUtils.writeVarInt(idStream, 0);
IOUtils.writeVarLong(idStream, length);
byte[] digest = messageDigest.digest();
File f = getFile(digest, false);
if (f.exists()) {
file.delete();
} else {
File parent = f.getParentFile();
if (!parent.exists()) {
parent.mkdirs();
}
file.renameTo(f);
}
IOUtils.writeVarInt(idStream, digest.length);
idStream.write(digest);
byte[] id = idStream.toByteArray();
String blobId = StringUtils.convertBytesToHex(id);
usesBlobId(blobId);
return blobId;
} catch (Exception e) {
throw ExceptionFactory.convert(e);
}
}
@Override
protected synchronized void storeBlock(byte[] digest, int level, byte[] data) throws IOException {
File f = getFile(digest, false);
if (f.exists()) {
return;
}
File parent = f.getParentFile();
if (!parent.exists()) {
parent.mkdirs();
}
File temp = new File(parent, f.getName() + ".temp");
OutputStream out = new FileOutputStream(temp, false);
out.write(data);
out.close();
temp.renameTo(f);
}
private File getFile(byte[] digest, boolean old) {
String id = StringUtils.convertBytesToHex(digest);
String sub = id.substring(id.length() - 2);
if (old) {
sub += OLD_SUFFIX;
}
return new File(new File(baseDir, sub), id + ".dat");
}
@Override
protected byte[] readBlockFromBackend(BlockId id) throws IOException {
File f = getFile(id.digest, false);
if (!f.exists()) {
File old = getFile(id.digest, true);
f.getParentFile().mkdir();
old.renameTo(f);
f = getFile(id.digest, false);
}
int length = (int) Math.min(f.length(), getBlockSize());
byte[] data = new byte[length];
InputStream in = new FileInputStream(f);
try {
IOUtils.skipFully(in, id.pos);
IOUtils.readFully(in, data, 0, length);
} finally {
in.close();
}
return data;
}
@Override
public void startMark() throws Exception {
mark = true;
for (int i = 0; i < 256; i++) {
String sub = StringUtils.convertBytesToHex(new byte[] { (byte) i });
File d = new File(baseDir, sub);
File old = new File(baseDir, sub + OLD_SUFFIX);
if (d.exists()) {
if (old.exists()) {
for (File p : d.listFiles()) {
String name = p.getName();
File newName = new File(old, name);
p.renameTo(newName);
}
} else {
d.renameTo(old);
}
}
}
markInUse();
}
@Override
protected boolean isMarkEnabled() {
return mark;
}
@Override
protected void mark(BlockId id) throws IOException {
File f = getFile(id.digest, false);
if (!f.exists()) {
File old = getFile(id.digest, true);
f.getParentFile().mkdir();
old.renameTo(f);
f = getFile(id.digest, false);
}
}
@Override
public int sweep() throws IOException {
int count = 0;
for (int i = 0; i < 256; i++) {
String sub = StringUtils.convertBytesToHex(new byte[] { (byte) i });
File old = new File(baseDir, sub + OLD_SUFFIX);
if (old.exists()) {
for (File p : old.listFiles()) {
String name = p.getName();
File file = new File(old, name);
file.delete();
count++;
}
old.delete();
}
}
mark = false;
return count;
}
}