/*
 * Copyright (c) 2016, 2018, Red Hat, Inc. All rights reserved.
 *
 * 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 EvilSyncBug
 * @summary Tests for crash/assert when attaching init thread during shutdown
 * @key gc
 * @library /test/lib
 * @modules java.base/jdk.internal.misc
 *          java.management
 * @run driver/timeout=480 EvilSyncBug
 */

import java.util.*;
import java.util.concurrent.*;
import java.util.concurrent.locks.*;

import jdk.test.lib.process.ProcessTools;
import jdk.test.lib.process.OutputAnalyzer;

public class EvilSyncBug {

    private static final int NUM_RUNS = 100;

    static Thread[] hooks = new MyHook[10000];

    public static void main(String[] args) throws Exception {
        if (args.length > 0) {
            test();
        } else {
            ExecutorService pool = Executors.newFixedThreadPool(Runtime.getRuntime().availableProcessors());

            Future<?>[] fs = new Future<?>[NUM_RUNS];

            for (int c = 0; c < NUM_RUNS; c++) {
                Callable<Void> task = () -> {
                    ProcessBuilder pb = ProcessTools.createJavaProcessBuilder("-Xms128m",
                                                                              "-Xmx128m",
                                                                              "-XX:+UnlockExperimentalVMOptions",
                                                                              "-XX:+UnlockDiagnosticVMOptions",
                                                                              "-XX:+UseShenandoahGC",
                                                                              "-XX:ShenandoahGCHeuristics=aggressive",
                                                                              "-XX:+ShenandoahStoreCheck",
                                                                              "EvilSyncBug", "test");
                    OutputAnalyzer output = new OutputAnalyzer(pb.start());
                    output.shouldHaveExitValue(0);
                    return null;
                };
                fs[c] = pool.submit(task);
            };

            for (Future<?> f : fs) {
              f.get();
            }

            pool.shutdown();
            pool.awaitTermination(1, TimeUnit.HOURS);
        }
    }

    private static void test() throws Exception {

        for (int t = 0; t < hooks.length; t++) {
          hooks[t] = new MyHook();
        }

        ExecutorService service = Executors.newFixedThreadPool(
          2,
          r -> {
            Thread t = new Thread(r);
            t.setDaemon(true);
            return t;
          }
        );

        List<Future<?>> futures = new ArrayList<>();
        for (int c = 0; c < 100; c++) {
          Runtime.getRuntime().addShutdownHook(hooks[c]);
          final Test[] tests = new Test[1000];
          for (int t = 0; t < tests.length; t++) {
            tests[t] = new Test();
          }

          Future<?> f1 = service.submit(() -> {
            Runtime.getRuntime().addShutdownHook(new MyHook());
            IntResult2 r = new IntResult2();
            for (Test test : tests) {
              test.RL_Us(r);
            }
          });
          Future<?> f2 = service.submit(() -> {
            Runtime.getRuntime().addShutdownHook(new MyHook());
            for (Test test : tests) {
              test.WLI_Us();
            }
          });

          futures.add(f1);
          futures.add(f2);
        }

        for (Future<?> f : futures) {
          f.get();
        }
    }

    public static class IntResult2 {
      int r1, r2;
    }

    public static class Test {
      final StampedLock lock = new StampedLock();

      int x, y;

      public void RL_Us(IntResult2 r) {
          StampedLock lock = this.lock;
          long stamp = lock.readLock();
          r.r1 = x;
          r.r2 = y;
          lock.unlock(stamp);
      }

      public void WLI_Us() {
          try {
              StampedLock lock = this.lock;
              long stamp = lock.writeLockInterruptibly();
              x = 1;
              y = 2;
              lock.unlock(stamp);
          } catch (InterruptedException e) {
              throw new RuntimeException(e);
          }
      }
    }

    private static class MyHook extends Thread {
        @Override
        public void run() {
            try {
                Thread.sleep(10);
            } catch (Exception e) {}
        }
    }

}