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 * 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.
 *
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 * questions.
 */

/* @test
 * @bug 8195160
 * @summary Spurious NPE from RdmaSocket.getIn/OutputStream
 * @requires (os.family == "linux")
 * @library .. /test/lib
 * @build RsocketTest
 * @run main/othervm -Djava.net.preferIPv4Stack=true Streams
 */

import java.io.IOException;
import java.lang.reflect.Constructor;
import java.net.ServerSocket;
import java.net.Socket;
import java.net.InetAddress;
import java.net.InetSocketAddress;
import java.util.concurrent.Phaser;
import jdk.net.Sockets;

// Racey test, will not always fail, but if it does then there is a problem.

public class Streams {
    static final int NUM_THREADS = 10;
    static volatile boolean failed;
    static ServerSocket ss;
    static final Phaser startingGate = new Phaser(NUM_THREADS + 1);
    static InetAddress ia;

    public static void main(String[] args) throws Exception {
        if (!RsocketTest.isRsocketAvailable())
            return;

        InetAddress ia = InetAddress.getLocalHost();

        try {
            ss = Sockets.openRdmaServerSocket();
            ss.bind(new InetSocketAddress(ia, 0));
            runTest(OutputStreamGetter.class);
            runTest(InputStreamGetter.class);
        } catch (Exception e) {
            e.printStackTrace();
            failed = true;
        } 

        if (failed)
            throw new RuntimeException("Failed, check output");
    }

    static void runTest(Class<? extends StreamGetter> klass)
        throws Exception
    {
        final int port = ss.getLocalPort();
        Socket[] sockets = new Socket[NUM_THREADS];

        for (int i = 0; i < NUM_THREADS; i++) {
            sockets[i] = Sockets.openRdmaSocket();
            final Socket cs = sockets[i];
            Thread t = new Thread() {
                public void run() {
                    try {
                        cs.connect(new InetSocketAddress(InetAddress.getLocalHost(), port));
                    } catch (Exception e) {
                        e.printStackTrace();
                        failed = true;
                    }
                }
            };
            t.start();
            Socket socket = ss.accept();
            cs.close();
        }

        Constructor<? extends StreamGetter> ctr = klass.getConstructor(Socket.class);

        Thread[] threads = new Thread[NUM_THREADS];
        for (int i=0; i<NUM_THREADS; i++)
            threads[i] = ctr.newInstance(sockets[i]);
        for (int i=0; i<NUM_THREADS; i++)
            threads[i].start();

        startingGate.arriveAndAwaitAdvance();
        for (int i=0; i<NUM_THREADS; i++)
            sockets[i].close();

        for (int i=0; i<NUM_THREADS; i++)
            threads[i].join();
    }

    static abstract class StreamGetter extends Thread {
        final Socket socket;
        StreamGetter(Socket s) { socket = s; }

        @Override
        public void run() {
            try {
                startingGate.arriveAndAwaitAdvance();
                getStream();
            } catch (IOException x) {
                // OK, socket may be closed
            } catch (NullPointerException x) {
                x.printStackTrace();
                failed = true;
            }
        }

        abstract void getStream() throws IOException;
    }

    static class InputStreamGetter extends StreamGetter {
        public InputStreamGetter(Socket s) { super(s); }
        void getStream() throws IOException {
            socket.getInputStream();
        }
    }

    static class OutputStreamGetter extends StreamGetter {
        public OutputStreamGetter(Socket s) { super(s); }
        void getStream() throws IOException {
            socket.getOutputStream();
        }
    }
}