/*
* Copyright Terracotta, Inc.
*
* Licensed 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.ehcache.impl.persistence;
import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
import org.ehcache.CachePersistenceException;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import java.io.File;
import java.nio.charset.Charset;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.util.ArrayDeque;
import java.util.Deque;
import java.util.HashSet;
import java.util.Locale;
import java.util.Set;
import static java.lang.Integer.toHexString;
import static java.nio.charset.Charset.forName;
/**
* A bunch of utility functions, mainly used by {@link DefaultLocalPersistenceService} and
* {@link FileBasedStateRepository} within this class.
*/
final class FileUtils {
private static final Logger LOGGER = LoggerFactory.getLogger(FileUtils.class);
private static final Charset UTF8 = forName("UTF8");
private static final int DEL = 0x7F;
private static final char ESCAPE = '%';
private static final Set<Character> ILLEGALS = new HashSet<Character>();
static {
ILLEGALS.add('/');
ILLEGALS.add('\\');
ILLEGALS.add('<');
ILLEGALS.add('>');
ILLEGALS.add(':');
ILLEGALS.add('"');
ILLEGALS.add('|');
ILLEGALS.add('?');
ILLEGALS.add('*');
ILLEGALS.add('.');
}
static void createLocationIfRequiredAndVerify(final File rootDirectory) {
if(!rootDirectory.exists()) {
if(!rootDirectory.mkdirs()) {
throw new IllegalArgumentException("Directory couldn't be created: " + rootDirectory.getAbsolutePath());
}
} else if(!rootDirectory.isDirectory()) {
throw new IllegalArgumentException("Location is not a directory: " + rootDirectory.getAbsolutePath());
}
if(!rootDirectory.canWrite()) {
throw new IllegalArgumentException("Location isn't writable: " + rootDirectory.getAbsolutePath());
}
}
static File createSubDirectory(File mainDirectory, String name) throws CachePersistenceException {
validateName(name);
File subDirectory = new File(mainDirectory, name);
create(subDirectory);
return subDirectory;
}
static void validateName(String name) {
if (!name.matches("[a-zA-Z0-9\\-_]+")) {
throw new IllegalArgumentException("Name is invalid for persistence context: " + name);
}
}
static void create(File directory) throws CachePersistenceException {
if (directory.isDirectory()) {
LOGGER.debug("Reusing {}", directory.getAbsolutePath());
} else if (directory.mkdir()) {
LOGGER.debug("Created {}", directory.getAbsolutePath());
} else if (directory.isDirectory()) {
// if create directory fails, check once more if it is due to concurrent creation.
LOGGER.debug("Reusing {}", directory.getAbsolutePath());
} else {
throw new CachePersistenceException("Unable to create or reuse directory: " + directory.getAbsolutePath());
}
}
static boolean recursiveDeleteDirectoryContent(File file) {
File[] contents = file.listFiles();
if (contents == null) {
throw new IllegalArgumentException("File " + file.getAbsolutePath() + " is not a directory");
} else {
boolean deleteSuccessful = true;
for (File f : contents) {
deleteSuccessful &= tryRecursiveDelete(f);
}
return deleteSuccessful;
}
}
private static boolean recursiveDelete(File file) {
Deque<File> toDelete = new ArrayDeque<File>();
toDelete.push(file);
while (!toDelete.isEmpty()) {
File target = toDelete.pop();
File[] contents = target.listFiles();
if (contents == null || contents.length == 0) {
if (target.exists() && !target.delete()) {
return false;
}
} else {
toDelete.push(target);
for (File f : contents) {
toDelete.push(f);
}
}
}
return true;
}
@SuppressFBWarnings("DM_GC")
static boolean tryRecursiveDelete(File file) {
boolean interrupted = false;
try {
for (int i = 0; i < 5; i++) {
if (recursiveDelete(file) || !isWindows()) {
return true;
} else {
System.gc();
System.runFinalization();
try {
Thread.sleep(50);
} catch (InterruptedException e) {
interrupted = true;
}
}
}
} finally {
if (interrupted) {
Thread.currentThread().interrupt();
}
}
return false;
}
private static boolean isWindows() {
return System.getProperty("os.name").toLowerCase(Locale.ENGLISH).contains("windows");
}
/**
* sanitize a name for valid file or directory name
*
* @param name the name to sanitize
* @return sanitized version of name
*/
static String safeIdentifier(String name) {
return safeIdentifier(name, true);
}
static String safeIdentifier(String name, boolean withSha1) {
int len = name.length();
StringBuilder sb = new StringBuilder(len);
for (int i = 0; i < len; i++) {
char c = name.charAt(i);
if (c <= ' ' || c >= DEL || ILLEGALS.contains(c) || c == ESCAPE) {
sb.append(ESCAPE);
sb.append(String.format("%04x", (int) c));
} else {
sb.append(c);
}
}
if (withSha1) {
sb.append("_").append(sha1(name));
}
return sb.toString();
}
private static String sha1(String input) {
StringBuilder sb = new StringBuilder();
for (byte b : getSha1Digest().digest(input.getBytes(UTF8))) {
sb.append(toHexString((b & 0xf0) >>> 4));
sb.append(toHexString((b & 0xf)));
}
return sb.toString();
}
private static MessageDigest getSha1Digest() {
try {
return MessageDigest.getInstance("SHA-1");
} catch (NoSuchAlgorithmException e) {
throw new AssertionError("All JDKs must have SHA-1");
}
}
}