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/*
* Copyright (c) 2009, 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 6693490
* @summary Pre-close file descriptor may inadvertently get registered with
* epoll during close
*/
import java.net.*;
import java.nio.channels.*;
import java.util.concurrent.*;
import java.util.*;
import java.io.IOException;
public class RegAfterPreClose {
static final int TEST_ITERATIONS = 300;
static volatile boolean done;
/**
* A task that continuously connects to a given address and immediately
* closes the connection.
*/
static class Connector implements Runnable {
private final SocketAddress sa;
Connector(int port) throws IOException {
InetAddress lh = InetAddress.getLocalHost();
this.sa = new InetSocketAddress(lh, port);
}
public void run() {
while (!done) {
try {
SocketChannel.open(sa).close();
} catch (IOException x) {
// back-off as probably resource related
try {
Thread.sleep(10);
} catch (InterruptedException ignore) { }
}
}
}
}
/**
* A task that closes a channel.
*/
static class Closer implements Runnable {
private final Channel channel;
Closer(Channel sc) {
this.channel = sc;
}
public void run() {
try {
channel.close();
} catch (IOException ignore) { }
}
}
public static void main(String[] args) throws Exception {
// create listener
InetSocketAddress isa = new InetSocketAddress(0);
ServerSocketChannel ssc = ServerSocketChannel.open();
ssc.socket().bind(isa);
// register with Selector
final Selector sel = Selector.open();
ssc.configureBlocking(false);
SelectionKey key = ssc.register(sel, SelectionKey.OP_ACCEPT);
ThreadFactory factory = new ThreadFactory() {
@Override
public Thread newThread(Runnable r) {
Thread t = new Thread(r);
t.setDaemon(true);
return t;
}
};
// create Executor that handles tasks that closes channels
// "asynchronously" - this creates the conditions to provoke the bug.
ExecutorService executor = Executors.newFixedThreadPool(2, factory);
// submit task that connects to listener
executor.execute(new Connector(ssc.socket().getLocalPort()));
// loop accepting connections until done (or an IOException is thrown)
int remaining = TEST_ITERATIONS;
while (remaining > 0) {
sel.select();
if (key.isAcceptable()) {
SocketChannel sc = ssc.accept();
if (sc != null) {
remaining--;
sc.configureBlocking(false);
sc.register(sel, SelectionKey.OP_READ);
executor.execute(new Closer(sc));
}
}
sel.selectedKeys().clear();
}
done = true;
sel.close();
executor.shutdown();
}
}
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