/*

 * Copyright (c) 2007, 2016, 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 4742177

 * @summary Re-test IPv6 (and specifically MulticastSocket) with latest Linux & USAGI code

 */

import java.util.*;

import java.net.*;

public class NoLoopbackPackets {

    private static String osname;

    static boolean isWindows() {

        if (osname == null)

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

        return osname.contains("Windows");

    }

    private static boolean hasIPv6() throws Exception {

        List<NetworkInterface> nics = Collections.list(

                                        NetworkInterface.getNetworkInterfaces());

        for (NetworkInterface nic : nics) {

            if (!nic.isLoopback()) {

                List<InetAddress> addrs = Collections.list(nic.getInetAddresses());

                for (InetAddress addr : addrs) {

                    if (addr instanceof Inet6Address) {

                        return true;

                    }

                }

            }

        }

        return false;

    }

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

        if (isWindows()) {

            System.out.println("The test only run on non-Windows OS. Bye.");

            return;

        }

        if (!hasIPv6()) {

            System.out.println("No IPv6 available. Bye.");

            return;

        }

        MulticastSocket msock = null;

        List<SocketAddress> failedGroups = new ArrayList<SocketAddress>();

        Sender sender = null;

        try {

            msock = new MulticastSocket();

            int port = msock.getLocalPort();

            // we will send packets to three multicast groups :-

            // 224.1.1.1, ::ffff:224.1.1.2, and ff02::1:1

            //

            List<SocketAddress> groups = new ArrayList<SocketAddress>();

            groups.add(new InetSocketAddress(InetAddress.getByName("224.1.1.1"), port));

            groups.add(new InetSocketAddress(InetAddress.getByName("::ffff:224.1.1.2"), port));

            groups.add(new InetSocketAddress(InetAddress.getByName("ff02::1:1"), port));

            sender = new Sender(groups);

            new Thread(sender).start();

            // Now try to receive multicast packets. we should not see any of them

            // since we disable loopback mode.

            //

            msock.setSoTimeout(5000);       // 5 seconds

            byte[] buf = new byte[1024];

            DatagramPacket packet = new DatagramPacket(buf, 0, buf.length);

            for (SocketAddress group : groups) {

                msock.joinGroup(group, null);

                try {

                    msock.receive(packet);

                    // it is an error if we receive something

                    failedGroups.add(group);

                } catch (SocketTimeoutException e) {

                    // we expect this

                }

                msock.leaveGroup(group, null);

            }

        } finally {

            if (msock != null) try { msock.close(); } catch (Exception e) {}

            if (sender != null) {

                sender.stop();

            }

        }

        if (failedGroups.size() > 0) {

            System.out.println("We should not receive anything from following groups, but we did:");

            for (SocketAddress group : failedGroups)

                System.out.println(group);

            throw new RuntimeException("test failed.");

        }

    }

    static class Sender implements Runnable {

        private List<SocketAddress> sendToGroups;

        private volatile boolean stop;

        public Sender(List<SocketAddress> groups) {

            sendToGroups = groups;

        }

        public void run() {

            byte[] buf = "hello world".getBytes();

            List<DatagramPacket> packets = new ArrayList<DatagramPacket>();

            try {

                for (SocketAddress group : sendToGroups) {

                    DatagramPacket packet = new DatagramPacket(buf, buf.length, group);

                    packets.add(packet);

                }

                MulticastSocket msock = new MulticastSocket();

                msock.setLoopbackMode(true);    // disable loopback mode

                while (!stop) {

                    for (DatagramPacket packet : packets) {

                        msock.send(packet);

                    }

                    Thread.sleep(1000);     // 1 second

                }

            } catch (Exception e) {

                throw new RuntimeException(e);

            }

        }

        void stop() {

            stop = true;

        }

    }

}