/*

 * Copyright (c) 2006, 2016, 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

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 * questions.

 */

/**

 * @test

 * @bug 6293795

 * @summary  Backend hangs when invokeMethod is called from a JDI eventHandler

 * @author jjh

 *

 * @library /test/lib

 * @modules java.management

 *          jdk.jdi

 *

 * @run build TestScaffold VMConnection TargetListener TargetAdapter

 * @run compile -g InvokeHangTest.java

 * @run driver InvokeHangTest

 */

import com.sun.jdi.*;

import com.sun.jdi.event.*;

import com.sun.jdi.request.*;

import java.util.*;

/*

 * This debuggee basically runs two threads each of

 * which loop, hitting a bkpt in each iteration.

 *

 */

class InvokeHangTarg extends Thread {

    static boolean one = false;

    static String name1 = "Thread 1";

    static String name2 = "Thread 2";

    static int count = 100;

    public static void main(String[] args) {

        System.out.println("Howdy!");

        InvokeHangTarg t1 = new InvokeHangTarg(name1);

        InvokeHangTarg t2 = new InvokeHangTarg(name2);

        t1.start();

        t2.start();

    }

    // This is called from the debugger via invokeMethod

    public double invokeee() {

        System.out.println("Debuggee: invokeee in thread "+Thread.currentThread().toString());

        return longMethod(2);

    }

    public double longMethod(int n) {

        double a = 0;

        double s = 0;

        for (int i = 0; i < n; i++) {

            a += i;

            for (int j = -1000*i; j < 1000*i; j++) {

                a = a*(1 + i/(j + 0.5));

                s += Math.sin(a);

            }

        }

        System.out.println("Debuggee: invokeee finished");

        return s;

    }

    public InvokeHangTarg(String name) {

        super(name);

    }

    public void run() {

        if (getName().equals(name1)) {

            run1();

        } else {

            run2();

        }

    }

    public void bkpt1(int i) {

        System.out.println("Debuggee: " + Thread.currentThread() +" is running:" + i);

        try {

            Thread.currentThread().sleep(2);

        } catch (InterruptedException iex) {}

        //yield();

    }

    public void run1() {

        int i = 0;

        while (i < count) {

            i++;

            bkpt1(i);

        }

    }

    public void bkpt2(int i) {

        System.out.println("Debuggee: " + Thread.currentThread() +" is running:" + i);

        try {

            Thread.currentThread().sleep(2);

        } catch (InterruptedException iex) {}

            //yield();

    }

    public void run2() {

        int i = 0;

        while (i < count) {

            i++;

            bkpt2(i);

        }

    }

}

/********** test program **********/

public class InvokeHangTest extends TestScaffold {

    ReferenceType targetClass;

    ThreadReference mainThread;

    BreakpointRequest request1;

    BreakpointRequest request2;

    static volatile int bkpts = 0;

    Thread timerThread;

    static long waitTime = jdk.test.lib.Utils.adjustTimeout(20000);

    InvokeHangTest (String args[]) {

        super(args);

    }

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

        new InvokeHangTest(args).startTests();

    }

    void doInvoke(ThreadReference thread, ObjectReference ref, String methodName) {

        List methods = ref.referenceType().methodsByName(methodName);

        Method method = (Method) methods.get(0);

        try {

            System.err.println("  Debugger: Invoking in thread" + thread);

            ref.invokeMethod(thread, method, new ArrayList(), ref.INVOKE_NONVIRTUAL);

            System.err.println("  Debugger: Invoke done");

        } catch (Exception ex) {

            ex.printStackTrace();

            failure("failure: Exception");

        }

    }

    // BreakpointEvent handler

    public void breakpointReached(BreakpointEvent event) {

        if (bkpts == 0) {

            /*

             * This thread will watch for n secs to go by with no

             * calls to this method.

             */

            timerThread.start();

        }

        synchronized("abc") {

            /*

             * Note that this will most likely never get to

             * the number of times the two bkpt lines in the debuggee

             * are hit because bkpts are lost while they are disabled.

             */

            bkpts++;

        }

        /*

         * The bug occurs when the requests are disabled

         * and then an invoke is done in the event handler.  In some cases

         * the other thread has hit a bkpt and the back-end is waiting

         * to send it.  When the back-end resumes the debuggee to do the

         * invokeMethod, this 2nd bkpt is released, the debuggee is suspended, including

         * the thread on which the invoke was done (because it is a SUSPEND_ALL bkpt),

         * the bkpt is sent to the front-end, but the client event handler is sitting

         * here waiting for the invoke to finish, so it doesn't get the 2nd bkpt and

         * do the resume for it.  Thus, the debuggee is suspended waiting for a resume

         * that never comes.

         */

        request1.disable();

        request2.disable();

        ThreadReference thread = event.thread();

        try {

            StackFrame sf = thread.frame(0);

            System.err.println("  Debugger: Breakpoint hit at "+sf.location());

            doInvoke(thread, sf.thisObject(), "invokeee");

        } catch (IncompatibleThreadStateException itsex) {

            itsex.printStackTrace();

            failure("failure: Exception");

        }

        request1.enable();

        request2.enable();

    }

    /********** test core **********/

    protected void runTests() throws Exception {

        /*

         * Get to the top of main()

         * to determine targetClass and mainThread

         */

        BreakpointEvent bpe = startToMain("InvokeHangTarg");

        targetClass = bpe.location().declaringType();

        mainThread = bpe.thread();

        EventRequestManager erm = vm().eventRequestManager();

        final Thread mainThread = Thread.currentThread();

        /*

         * Set event requests

         */

        Location loc1 = findMethod(targetClass, "bkpt1", "(I)V").location();

        Location loc2 = findMethod(targetClass, "bkpt2", "(I)V").location();

        request1 = erm.createBreakpointRequest(loc1);

        request2 = erm.createBreakpointRequest(loc2);

        request1.enable();

        request2.enable();

        /*

         * This thread will be started when we get the first bkpt.

         * (Which we always expect to get).

         * It awakens every n seconds and checks to see if we

         * got any breakpoint events while it was asleep.  If not, then

         * we assume the debuggee is hung and fail the test.

         */

        timerThread = new Thread("test timer") {

                public void run() {

                    int myBkpts = bkpts;

                    while (true) {

                        try {

                            Thread.sleep(waitTime);

                            System.out.println("bkpts = " + bkpts);

                            if (myBkpts == bkpts) {

                                // no bkpt for 'waitTime' msecs

                                failure("failure: Debuggee appears to be hung");

                                vmDisconnected = true;

                                // This awakens the main thread which is

                                // waiting for a VMDisconnect.

                                mainThread.interrupt();

                                break;

                            }

                            myBkpts = bkpts;

                        } catch (InterruptedException ee) {

                            // If the test completes, this occurs.

                            println("timer Interrupted");

                            break;

                        }

                    }

                }

            };

        /*

         * resume the target, listening for events

         */

        listenUntilVMDisconnect();

        timerThread.interrupt();

        /*

         * deal with results of test

         * if anything has called failure("foo") testFailed will be true

         */

        if (!testFailed) {

            println("InvokeHangTest: passed; bkpts = " + bkpts);

        } else {

            throw new Exception("InvokeHangTest: failed; bkpts = " + bkpts);

        }

    }

}