/*

 * Copyright (c) 2003, 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 4499763

 * @summary Check for race condition between close and available

 */

import java.io.*;

/*

 * Note: this is a probabalistic test and will not always fail on

 * a workspace where the race condition can occur. However it should

 * never fail on a workspace where the bug has been fixed.

 */

public class CloseAndAvailableRC {

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

        CloseAndAvailableRC rc = new CloseAndAvailableRC();

        rc.go();

    }

    private PipedInputStream inPipe = null;

    private PipedOutputStream outPipe = null;

    private Thread sink = null;

    private volatile boolean stop = false;

    private volatile boolean stopTest = false;

    private void go() throws Exception {

        for (long i=0; i<2000; i++) {

            if (stopTest) {

                cleanup();

                throw new RuntimeException("Test failed");

            }

            resetPipes();

            System.err.println("Closing...");

            inPipe.close();

        }

        cleanup();

    }

    // Cleanup old threads

    private void cleanup() throws Exception {

        if (sink != null) {

            stop = true;

            sink.interrupt();

            try {

                sink.join();

            } catch (InterruptedException e) {

            }

            stop = false;

            // Input Stream will have been closed already

            outPipe.close();

        }

    }

    private void resetPipes() throws Exception {

        cleanup();

        // Init pipe; Note: output never read

        inPipe = new PipedInputStream();

        outPipe = new PipedOutputStream(inPipe);

        // Put stuff in pipe so that available() > 0

        for (byte b = 0; b < 10; b++)

            outPipe.write(b);

        sink = new Sink();

        sink.start();

    }

    private class Sink extends Thread {

        public void run() {

            while (!stop) {

                try {

                    final int num = inPipe.available();

                    if (num < 0) {

                        // Bug detected; stop the test

                        stopTest = true;

                    }

                } catch (final IOException e) {

                    System.err.println("Error on available:" + e.getMessage());

                    e.printStackTrace(System.err);

                }

            }

        }

    }

}