/*

 * Copyright 2007-2008 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,

 * CA 95054 USA or visit www.sun.com if you need additional information or

 * have any questions.

 */

/* @test

 * @bug 4527345

 * @summary Unit test for DatagramChannel's multicast support

 * @build MulticastSendReceiveTests NetworkConfiguration

 */

import java.nio.ByteBuffer;

import java.nio.channels.*;

import java.net.*;

import java.util.*;

import java.io.IOException;

public class MulticastSendReceiveTests {

    static Random rand = new Random();

    /**

     * Send datagram from given local address to given multicast

     * group.

     */

    static int sendDatagram(InetAddress local,

                            NetworkInterface nif,

                            InetAddress group,

                            int port)

        throws IOException

    {

        ProtocolFamily family = (group instanceof Inet6Address) ?

            StandardProtocolFamily.INET6 : StandardProtocolFamily.INET;

        DatagramChannel dc = DatagramChannel.open(family)

            .bind(new InetSocketAddress(local, 0))

            .setOption(StandardSocketOption.IP_MULTICAST_IF, nif);

        int id = rand.nextInt();

        byte[] msg = Integer.toString(id).getBytes("UTF-8");

        ByteBuffer buf = ByteBuffer.wrap(msg);

        System.out.format("Send message from %s -> group %s (id=0x%x)\n",

            local.getHostAddress(), group.getHostAddress(), id);

        dc.send(buf, new InetSocketAddress(group, port));

        dc.close();

        return id;

    }

    /**

     * Wait (with timeout) for datagram.

     *

     * @param   expectedSender - expected sender address, or

     *                           null if no datagram expected

     * @param   id - expected id of datagram

     */

    static void receiveDatagram(DatagramChannel dc,

                                InetAddress expectedSender,

                                int id)

        throws IOException

    {

        Selector sel = Selector.open();

        dc.configureBlocking(false);

        dc.register(sel, SelectionKey.OP_READ);

        ByteBuffer buf = ByteBuffer.allocateDirect(100);

        try {

            for (;;) {

                System.out.println("Waiting to receive message");

                sel.select(5*1000);

                SocketAddress sa = dc.receive(buf);

                // no datagram received

                if (sa == null) {

                    if (expectedSender != null) {

                        throw new RuntimeException("Expected message not recieved");

                    }

                    System.out.println("No message received (correct)");

                    return;

                }

                // datagram received

                InetAddress sender = ((InetSocketAddress)sa).getAddress();

                buf.flip();

                byte[] bytes = new byte[buf.remaining()];

                buf.get(bytes);

                int receivedId = Integer.parseInt(new String(bytes));

                System.out.format("Received message from %s (id=0x%x)\n",

                    sender, receivedId);

                if (expectedSender == null) {

                    if (receivedId == id)

                        throw new RuntimeException("Message not expected");

                    System.out.println("Message ignored (has wrong id)");

                } else {

                    if (sender.equals(expectedSender)) {

                        System.out.println("Message expected");

                        return;

                    }

                    System.out.println("Message ignored (wrong sender)");

                }

                sel.selectedKeys().clear();

                buf.rewind();

            }

        } finally {

            sel.close();

        }

    }

    /**

     * Exercise multicast send/receive on given group/interface

     */

    static void test(NetworkInterface nif, InetAddress group, InetAddress source)

        throws IOException

    {

        ProtocolFamily family = (group instanceof Inet6Address) ?

            StandardProtocolFamily.INET6 : StandardProtocolFamily.INET;

        System.out.format("create channel to %s socket\n", family.name());

        DatagramChannel dc = DatagramChannel.open(family)

            .setOption(StandardSocketOption.SO_REUSEADDR, true)

            .bind(new InetSocketAddress(0));

        // join group

        System.out.format("join %s @ %s\n", group.getHostAddress(),

            nif.getName());

        MembershipKey key = dc.join(group, nif);

        // send message to group

        int port = ((InetSocketAddress)dc.getLocalAddress()).getPort();

        int id = sendDatagram(source, nif, group, port);

        // receive message and check id matches

        receiveDatagram(dc, source, id);

        // exclude-mode filtering

        try {

            System.out.format("block %s\n", source.getHostAddress());

            // may throw UOE

            key.block(source);

            id = sendDatagram(source, nif, group, port);

            receiveDatagram(dc, null, id);

            // unblock source, send message, message should be received

            System.out.format("unblock %s\n", source.getHostAddress());

            key.unblock(source);

            id = sendDatagram(source, nif, group, port);

            receiveDatagram(dc, source, id);

        } catch (UnsupportedOperationException x) {

            System.out.println("Exclude-mode filtering not supported!");

        }

        key.drop();

        // include-mode filtering

        InetAddress bogus = (group instanceof Inet6Address) ?

            InetAddress.getByName("fe80::1234") :

            InetAddress.getByName("1.2.3.4");

        System.out.format("join %s @ %s only-source %s\n", group.getHostAddress(),

            nif.getName(), bogus.getHostAddress());

        try {

            // may throw UOE

            key = dc.join(group, nif, bogus);

            id = sendDatagram(source, nif, group, port);

            receiveDatagram(dc, null, id);

            System.out.format("join %s @ %s only-source %s\n", group.getHostAddress(),

                nif.getName(), source.getHostAddress());

            key = dc.join(group, nif, source);

            id = sendDatagram(source, nif, group, port);

            receiveDatagram(dc, source, id);

        } catch (UnsupportedOperationException x) {

            System.out.println("Include-mode filtering not supported!");

        }

        // done

        dc.close();

    }

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

        NetworkConfiguration config = NetworkConfiguration.probe();

        // multicast groups used for the test

        InetAddress ip4Group = InetAddress.getByName("225.4.5.6");

        InetAddress ip6Group = InetAddress.getByName("ff02::a");

        for (NetworkInterface nif: config.ip4Interfaces()) {

            InetAddress source = config.ip4Addresses(nif).iterator().next();

            test(nif, ip4Group, source);

        }

        for (NetworkInterface nif: config.ip6Interfaces()) {

            InetAddress source = config.ip6Addresses(nif).iterator().next();

            test(nif, ip6Group, source);

        }

    }

}