/*
* Copyright (c) 2001, 2010, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
/* @test
* @bug 4429043 4493595 6332756 6709457
* @summary The FileChannel file locking
*/
import java.io.*;
import java.nio.channels.*;
import static java.nio.file.StandardOpenOption.*;
/**
* Testing FileChannel's lock method.
*/
public class Lock {
public static void main(String[] args) throws Exception {
if (args.length > 0) {
if(args[0].equals("1")) {
MadWriter mw = new MadWriter(args[1], false);
} else {
MadWriter mw = new MadWriter(args[1], true);
}
return;
}
File blah = File.createTempFile("blah", null);
blah.deleteOnExit();
RandomAccessFile raf = new RandomAccessFile(blah, "rw");
raf.write(1);
raf.close();
test1(blah, "1");
test1(blah, "2");
test2(blah, true);
test2(blah, false);
test3(blah);
test4(blah);
blah.delete();
}
private static void test2(File blah, boolean b) throws Exception {
RandomAccessFile raf = new RandomAccessFile(blah, "rw");
FileChannel channel = raf.getChannel();
FileLock lock;
if (b)
lock = channel.lock();
else
lock = channel.tryLock();
lock.release();
channel.close();
}
static void test1(File blah, String str) throws Exception {
// Grab the lock
RandomAccessFile fis = new RandomAccessFile(blah, "rw");
FileChannel fc = fis.getChannel();
FileLock lock = null;
if (str.equals("1")) {
lock = fc.lock(0, 10, false);
if (lock == null)
throw new RuntimeException("Lock should not return null");
try {
FileLock lock2 = fc.lock(5, 10, false);
throw new RuntimeException("Overlapping locks allowed");
} catch (OverlappingFileLockException e) {
// Correct result
}
}
// Exec the tamperer
String command = System.getProperty("java.home") +
File.separator + "bin" + File.separator + "java";
String testClasses = System.getProperty("test.classes");
if (testClasses != null)
command += " -cp " + testClasses;
command += " Lock " + str + " " + blah;
Process p = Runtime.getRuntime().exec(command);
BufferedReader in = new BufferedReader
(new InputStreamReader(p.getInputStream()));
String s;
int count = 0;
while ((s = in.readLine()) != null) {
if (!s.equals("good")) {
if (File.separatorChar == '/') {
// Fails on windows over NFS...
throw new RuntimeException("Failed: "+s);
}
}
count++;
}
if (count == 0) {
in = new BufferedReader(new InputStreamReader(p.getErrorStream()));
while ((s = in.readLine()) != null) {
System.err.println("Error output: " + s);
}
throw new RuntimeException("Failed, no output");
}
// Clean up
if (lock != null) {
/* Check multiple releases */
lock.release();
lock.release();
}
fc.close();
fis.close();
}
// The overlap check for file locks should be JVM-wide
private static void test3(File blah) throws Exception {
FileChannel fc1 = new RandomAccessFile(blah, "rw").getChannel();
FileChannel fc2 = new RandomAccessFile(blah, "rw").getChannel();
// lock via one channel, and then attempt to lock the same file
// using a second channel
FileLock fl1 = fc1.lock();
try {
fc2.tryLock();
throw new RuntimeException("Overlapping locks allowed");
} catch (OverlappingFileLockException x) {
}
try {
fc2.lock();
throw new RuntimeException("Overlapping locks allowed");
} catch (OverlappingFileLockException x) {
}
// release lock and the attempt to lock with the second channel
// should succeed.
fl1.release();
FileLock fl2 = fc2.lock();
try {
fc1.lock();
throw new RuntimeException("Overlapping locks allowed");
} catch (OverlappingFileLockException x) {
}
fc1.close();
fc2.close();
}
/**
* Test file locking when file is opened for append
*/
static void test4(File blah) throws Exception {
try (FileChannel fc = new FileOutputStream(blah, true).getChannel()) {
fc.tryLock().release();
fc.tryLock(0L, 1L, false).release();
fc.lock().release();
fc.lock(0L, 1L, false).release();
}
try (FileChannel fc = FileChannel.open(blah.toPath(), APPEND)) {
fc.tryLock().release();
fc.tryLock(0L, 1L, false).release();
fc.lock().release();
fc.lock(0L, 1L, false).release();
}
}
}
class MadWriter {
public MadWriter(String s, boolean b) throws Exception {
File f = new File(s);
RandomAccessFile fos = new RandomAccessFile(f, "rw");
FileChannel fc = fos.getChannel();
if (fc.tryLock(10, 10, false) == null) {
System.out.println("bad: Failed to grab adjacent lock");
}
FileLock lock = fc.tryLock(0, 10, false);
if (lock == null) {
if (b)
System.out.println("bad");
else
System.out.println("good");
} else {
if (b)
System.out.println("good");
else
System.out.println("bad");
}
fc.close();
fos.close();
}
}