/*

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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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import java.lang.management.ManagementFactory;

import java.lang.management.ThreadInfo;

import java.security.CodeSource;

import java.security.Permission;

import java.security.PermissionCollection;

import java.security.Permissions;

import java.security.Policy;

import java.security.ProtectionDomain;

import java.util.Enumeration;

import java.util.concurrent.Semaphore;

import java.util.concurrent.atomic.AtomicBoolean;

import java.util.concurrent.atomic.AtomicInteger;

import java.util.logging.LogManager;

import java.util.logging.Logger;

/**

 * @test

 * @bug 8065991

 * @summary check that when LogManager is initialized, a deadlock similar

 *          to that described in 8065709 will not occur.

 * @modules java.base/sun.misc

 * @run main/othervm LogManagerAppContextDeadlock UNSECURE

 * @run main/othervm LogManagerAppContextDeadlock SECURE

 *

 * @author danielfuchs

 */

public class LogManagerAppContextDeadlock {

    public static final Semaphore sem = new Semaphore(0);

    public static final Semaphore sem2 = new Semaphore(0);

    public static final Semaphore sem3 = new Semaphore(-2);

    public static volatile boolean goOn = true;

    public static volatile Exception thrown;

    // Emulate EventQueue

    static class FakeEventQueue {

        static final Logger logger = Logger.getLogger("foo");

    }

    // Emulate AppContext

    static class FakeAppContext {

        static final class FakeAppContextLock {}

        static final FakeAppContextLock lock = new FakeAppContextLock();

        static volatile FakeAppContext appContext;

        final FakeEventQueue queue;

        FakeAppContext() {

            appContext = this;

            numAppContexts.incrementAndGet();

            // release sem2 to let Thread t2 call Logger.getLogger().

            sem2.release();

            try {

                // Wait until we JavaAWTAccess is called by LogManager.

                // Thread 2 will call Logger.getLogger() which will

                // trigger a call to JavaAWTAccess - which will release

                // sem, thus ensuring that Thread #2 is where we want it.

                sem.acquire();

                System.out.println("Sem acquired: Thread #2 has called JavaAWTAccess");

            } catch(InterruptedException x) {

                Thread.interrupted();

            }

            queue = new FakeEventQueue();

        }

        static FakeAppContext getAppContext() {

            synchronized (lock) {

                if (numAppContexts.get() == 0) {

                    return new FakeAppContext();

                }

                return appContext;

            }

        }

        static {

            sun.misc.SharedSecrets.setJavaAWTAccess(new sun.misc.JavaAWTAccess() {

                @Override

                public Object getAppletContext() {

                    if (numAppContexts.get() == 0) return null;

                    // We are in JavaAWTAccess, we can release sem and let

                    // FakeAppContext constructor proceeed.

                    System.out.println("Releasing Sem");

                    sem.release();

                    return getAppContext();

                }

            });

        }

    }

    // Test with or without a security manager

    public static enum TestCase {

        UNSECURE, SECURE;

        public void run() throws Exception {

            System.out.println("Running test case: " + name());

            Configure.setUp(this);

            test(this);

        }

    }

    public static void test(TestCase test) throws Exception {

        Thread t1 = new Thread() {

            @Override

            public void run() {

                sem3.release();

                System.out.println("FakeAppContext.getAppContext()");

                FakeAppContext.getAppContext();

                System.out.println("Done: FakeAppContext.getAppContext()");

            }

        };

        t1.setDaemon(true);

        t1.start();

        Thread t2 = new Thread() {

            public void run() {

                sem3.release();

                try {

                    // Wait until Thread1 is in FakeAppContext constructor

                    sem2.acquire();

                    System.out.println("Sem2 acquired: Thread #1 will be waiting to acquire Sem");

                } catch (InterruptedException ie) {

                    Thread.interrupted();

                }

                System.out.println("Logger.getLogger(name).info(name)");

                Logger.getLogger(test.name());//.info(name);

                System.out.println("Done: Logger.getLogger(name).info(name)");

            }

        };

        t2.setDaemon(true);

        t2.start();

        System.out.println("Should exit now...");

        Thread detector = new DeadlockDetector();

        detector.start();

        // Wait for the 3 threads to start

        sem3.acquire();

        // Now wait for t1 & t2 to finish, or for a deadlock to be detected.

        while (goOn && (t1.isAlive() || t2.isAlive())) {

            if (t2.isAlive()) t2.join(1000);

            if (test == TestCase.UNSECURE && System.getSecurityManager() == null) {

                // if there's no security manager, AppContext.getAppContext() is

                // not called -  so Thread t2 will not end up calling

                // sem.release(). In that case we must release the semaphore here

                // so that t1 can proceed.

                if (LogManager.getLogManager().getLogger(TestCase.UNSECURE.name()) != null) {

                    // means Thread t2 has created the logger

                    sem.release();

                }

            }

            if (t1.isAlive()) t1.join(1000);

        }

        if (thrown != null) {

            throw thrown;

        }

    }

    // Thrown by the deadlock detector

    static final class DeadlockException extends RuntimeException {

        public DeadlockException(String message) {

            super(message);

        }

        @Override

        public void printStackTrace() {

        }

    }

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

        if (args.length == 0) {

            args = new String[] { "SECURE" };

        }

        // If we don't initialize LogManager here, there will be

        // a deadlock.

        // See <https://bugs.openjdk.java.net/browse/JDK-8065709?focusedCommentId=13582038&page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#comment-13582038>

        // for more details.

        Logger.getLogger("main").info("starting...");

        try {

            TestCase.valueOf(args[0]).run();

            System.out.println("Test "+args[0]+" Passed");

        } catch(Throwable t) {

            System.err.println("Test " + args[0] +" failed: " + t);

            t.printStackTrace();

        }

    }

    // Called by the deadlock detector when a deadlock is found.

    static void fail(Exception x) {

        x.printStackTrace();

        if (thrown == null) {

            thrown = x;

        }

        goOn = false;

    }

    // A thread that detect deadlocks.

        public DeadlockDetector() {

            this.setDaemon(true);

        }

        @Override

        public void run() {

            sem3.release();

            Configure.doPrivileged(this::loop);

        }

        public void loop() {

            while(goOn) {

                try {

                    long[] ids = ManagementFactory.getThreadMXBean().findDeadlockedThreads();

                    ids = ids == null ? new long[0] : ids;

                    if (ids.length == 1) {

                        throw new RuntimeException("Found 1 deadlocked thread: "+ids[0]);

                    } else if (ids.length > 0) {

                        ThreadInfo[] infos = ManagementFactory.getThreadMXBean().getThreadInfo(ids, Integer.MAX_VALUE);

                        System.err.println("Found "+ids.length+" deadlocked threads: ");

                        for (ThreadInfo inf : infos) {

                            System.err.println(inf);

                        }

                        throw new DeadlockException("Found "+ids.length+" deadlocked threads");

                    }

                    Thread.sleep(100);

                } catch(InterruptedException | RuntimeException x) {

                    fail(x);

                }

            }

        }

    }

    // A helper class to configure the security manager for the test,

    // and bypass it when needed.

    static class Configure {

        static Policy policy = null;

        static final ThreadLocal<AtomicBoolean> allowAll = new ThreadLocal<AtomicBoolean>() {

            @Override

            protected AtomicBoolean initialValue() {

                return  new AtomicBoolean(false);

            }

        };

        static void setUp(TestCase test) {

            switch (test) {

                case SECURE:

                    if (policy == null && System.getSecurityManager() != null) {

                        throw new IllegalStateException("SecurityManager already set");

                    } else if (policy == null) {

                        policy = new SimplePolicy(TestCase.SECURE, allowAll);

                        Policy.setPolicy(policy);

                        System.setSecurityManager(new SecurityManager());

                    }

                    if (System.getSecurityManager() == null) {

                        throw new IllegalStateException("No SecurityManager.");

                    }

                    if (policy == null) {

                        throw new IllegalStateException("policy not configured");

                    }

                    break;

                case UNSECURE:

                    if (System.getSecurityManager() != null) {

                        throw new IllegalStateException("SecurityManager already set");

                    }

                    break;

                default:

                    new InternalError("No such testcase: " + test);

            }

        }

        static void doPrivileged(Runnable run) {

            allowAll.get().set(true);

            try {

                run.run();

            } finally {

                allowAll.get().set(false);

            }

        }

    }

    // A Helper class to build a set of permissions.

        final Permissions perms;

        public PermissionsBuilder() {

            this(new Permissions());

        }

        public PermissionsBuilder(Permissions perms) {

            this.perms = perms;

        }

        public PermissionsBuilder add(Permission p) {

            perms.add(p);

            return this;

        }

        public PermissionsBuilder addAll(PermissionCollection col) {

            if (col != null) {

                for (Enumeration<Permission> e = col.elements(); e.hasMoreElements(); ) {

                    perms.add(e.nextElement());

                }

            }

            return this;

        }

        public Permissions toPermissions() {

            final PermissionsBuilder builder = new PermissionsBuilder();

            builder.addAll(perms);

            return builder.perms;

        }

    }

    // Policy for the test...

    public static class SimplePolicy extends Policy {

        final Permissions permissions;

        final Permissions allPermissions;

        final ThreadLocal<AtomicBoolean> allowAll; // actually: this should be in a thread locale

        public SimplePolicy(TestCase test, ThreadLocal<AtomicBoolean> allowAll) {

            this.allowAll = allowAll;

            // we don't actually need any permission to create our

            // FileHandlers because we're passing invalid parameters

            // which will make the creation fail...

            permissions = new Permissions();

            permissions.add(new RuntimePermission("accessClassInPackage.sun.misc"));

            // these are used for configuring the test itself...

            allPermissions = new Permissions();

            allPermissions.add(new java.security.AllPermission());

        }

        @Override

        public boolean implies(ProtectionDomain domain, Permission permission) {

            if (allowAll.get().get()) return allPermissions.implies(permission);

            return permissions.implies(permission);

        }

        @Override

        public PermissionCollection getPermissions(CodeSource codesource) {

            return new PermissionsBuilder().addAll(allowAll.get().get()

                    ? allPermissions : permissions).toPermissions();

        }

        @Override

        public PermissionCollection getPermissions(ProtectionDomain domain) {

            return new PermissionsBuilder().addAll(allowAll.get().get()

                    ? allPermissions : permissions).toPermissions();

        }

    }

}