/*

 * Copyright (c) 2018, 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 8201315

 * @build SelectorUtils

 * @run main RegisterDuringSelect

 * @summary Test that channels can be registered, interest ops can changed,

 *          and keys cancelled while a selection operation is in progress.

 */

import java.io.IOException;

import java.nio.channels.Pipe;

import java.nio.channels.SelectionKey;

import java.nio.channels.Selector;

public class RegisterDuringSelect {

    interface TestOperation {

        void accept(Thread t, Selector sel, Pipe.SourceChannel sc) throws Exception;

    }

    static class Test {

        final Selector sel;

        final Pipe p;

        final Pipe.SourceChannel sc;

        Test() throws Exception {

            sel = Selector.open();

            p = Pipe.open();

            sc = p.source();

            sc.configureBlocking(false);

        }

        void test(TestOperation op) throws Exception {

            try {

                Thread t = new Thread(() -> {

                    try {

                        sel.select();

                    } catch (IOException ex) {

                        throw new RuntimeException(ex);

                    }

                });

                t.start();

                op.accept(t, sel, sc);

            } finally {

                sel.close();

                p.source().close();

                p.sink().close();

            }

        }

    }

    /**

     * Invoke register, interestOps, and cancel concurrently with a thread

     * doing a selection operation

     */

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

        new Test().test((t, sel, sc) -> {

            System.out.println("register ...");

            // spin until make sure select is invoked

            SelectorUtils.spinUntilLocked(t, sel);

            SelectionKey key = sc.register(sel, SelectionKey.OP_READ);

            try {

                if (!sel.keys().contains(key))

                    throw new RuntimeException("key not in key set");

            } finally {

                sel.wakeup();

                t.join();

            }

        });

        new Test().test((t, sel, sc) -> {

            System.out.println("interestOps ...");

            SelectionKey key = sc.register(sel, SelectionKey.OP_READ);

            // spin until make sure select is invoked

            SelectorUtils.spinUntilLocked(t, sel);

            key.interestOps(0);

            try {

                if (key.interestOps() != 0)

                    throw new RuntimeException("interested ops not cleared");

            } finally {

                sel.wakeup();

                t.join();

            }

        });

        new Test().test((t, sel, sc) -> {

            System.out.println("cancel ...");

            SelectionKey key = sc.register(sel, SelectionKey.OP_READ);

            // spin until make sure select is invoked

            SelectorUtils.spinUntilLocked(t, sel);

            key.cancel();

            sel.wakeup();

            t.join();

            if (sel.keys().contains(key))

                throw new RuntimeException("key not removed from key set");

        });

    }

}