/*

 * Copyright (c) 2007, 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 6403933

 * @summary POLLHUP or POLLERR on "idle" key can cause Selector to spin

 */

import java.io.*;

import java.net.*;

import java.nio.*;

import java.nio.channels.*;

import java.net.*;

import java.nio.channels.*;

public class CloseWhenKeyIdle {

    // indicates if the wakeup has happened

    static volatile boolean wakeupDone = false;

    // Wakes up a Selector after a given delay

    static class Waker implements Runnable {

        private Selector sel;

        private long delay;

        Waker(Selector sel, long delay) {

            this.sel = sel;

            this.delay = delay;

        }

        public void run() {

            try {

                Thread.sleep(delay);

                wakeupDone = true;

                sel.wakeup();

            } catch (Exception x) {

                x.printStackTrace();

            }

        }

    }

    public static void main(String[] args) throws Exception {

        // Skip test on pre-2.6 kernels until the poll SelectorProvider

        // is updated

        String osname = System.getProperty("os.name");

        if (osname.equals("Linux")) {

            String[] ver = System.getProperty("os.version").split("\\.", 0);

            if (ver.length >=2 ) {

                int major = Integer.parseInt(ver[0]);

                int minor = Integer.parseInt(ver[1]);

                if (major < 2 || (major == 2 && minor < 6)) {

                    System.out.println("Test passing on pre-2.6 kernel");

                    return;

                }

            }

        }

        // establish loopback connection

        ServerSocketChannel ssc = ServerSocketChannel.open();

        ssc.socket().bind(new InetSocketAddress(0));

        SocketAddress remote = new InetSocketAddress(InetAddress.getLocalHost(),

            ssc.socket().getLocalPort());

        SocketChannel sc1 = SocketChannel.open(remote);

        SocketChannel sc2 = ssc.accept();

        // register channel for one end with a Selector, interest set = 0

        Selector sel = Selector.open();

        sc1.configureBlocking(false);

        SelectionKey k = sc1.register(sel, 0);

        sel.selectNow();

        // hard close to provoke POLLHUP

        sc2.socket().setSoLinger(true, 0);

        sc2.close();

        // schedule wakeup after a few seconds

        Thread t = new Thread(new Waker(sel, 5000));

        t.setDaemon(true);

        t.start();

        // select should block

        int spinCount = 0;

        boolean failed = false;

        for (;;) {

            int n = sel.select();

            if (n > 0) {

                System.err.println("Channel should not be selected!!!");

                failed = true;

                break;

            }

            // wakeup

            if (wakeupDone)

                break;

            // wakeup for no reason - if it happens a few times then we have a

            // problem

            spinCount++;

            if (spinCount >= 3) {

                System.err.println("Selector appears to be spinning");

                failed = true;

                break;

            }

        }

        sc1.close();

        sel.close();

        if (failed)

            throw new RuntimeException("Test failed");

        System.out.println("PASS");

    }

}