/*

 * Copyright (c) 2001, 2002, 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 4686717

 * @summary Test MulticastSocket.setLoopbackMode

 * @library /test/lib

 * @run main/othervm SetLoopbackMode

 */

import java.net.*;

import java.io.IOException;

import java.util.Enumeration;

import jdk.test.lib.NetworkConfiguration;

public class SetLoopbackMode {

    static final boolean FAILED = true;

    static final boolean PASSED = false;

    static boolean test(MulticastSocket mc, InetAddress grp) throws IOException {

        boolean disabled = mc.getLoopbackMode();

        if (disabled) {

            System.out.println("Loopback mode is disabled.");

        } else {

            System.out.println("Loopback mode is enabled.");

        }

        byte b[] = "hello".getBytes();

        DatagramPacket p = new DatagramPacket(b, b.length, grp,

                                mc.getLocalPort());

        mc.send(p);

        boolean gotPacket = false;

        mc.setSoTimeout(1000);

        try {

            b = new byte[16];

            p = new DatagramPacket(b, b.length);

            mc.receive(p);

            gotPacket = true;

            /* purge any additional copies of the packet */

            for (;;) {

                mc.receive(p);

            }

        } catch (SocketTimeoutException x) {

        }

        if (gotPacket && disabled) {

            System.out.println("Packet received (unexpected as loopback is disabled)");

            return FAILED;

        }

        if (!gotPacket && !disabled) {

            System.out.println

                ("Packet not received (packet excepted as loopback is enabled)");

            return FAILED;

        }

        if (gotPacket && !disabled) {

            System.out.println("Packet received - correct.");

        } else {

            System.out.println("Packet not received - correct.");

        }

        return PASSED;

    }

    private static boolean canUseIPv6(NetworkConfiguration nc) {

        return nc.ip6MulticastInterfaces().toArray().length > 0;

    }

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

        int failures = 0;

        NetworkConfiguration nc = NetworkConfiguration.probe();

        MulticastSocket mc = new MulticastSocket();

        InetAddress grp = InetAddress.getByName("224.80.80.80");

        /*

         * If IPv6 is available then use IPv6 multicast group - needed

         * to workaround Linux IPv6 bug whereby !IPV6_MULTICAST_LOOP

         * doesn't prevent loopback of IPv4 multicast packets.

         */

        if (canUseIPv6(nc)) {

            grp = InetAddress.getByName("ff01::1");

        }

        //mc.setNetworkInterface(NetworkInterface.getByInetAddress(lb));

        System.out.println("\nTest will use multicast group: " + grp);

        mc.joinGroup(grp);

        System.out.println("\n******************\n");

        mc.setLoopbackMode(true);

        if (test(mc, grp) == FAILED) failures++;

        System.out.println("\n******************\n");

        mc.setLoopbackMode(false);

        if (test(mc, grp) == FAILED) failures++;

        System.out.println("\n******************\n");

        if (failures > 0) {

            throw new RuntimeException("Test failed");

        }

    }

}