/*

 * Copyright (c) 1999, 2019, 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.

 *

 */

#ifndef SHARE_PRIMS_JVMTIRAWMONITOR_HPP

#define SHARE_PRIMS_JVMTIRAWMONITOR_HPP

#include "memory/allocation.hpp"

#include "runtime/park.hpp"

#include "utilities/growableArray.hpp"

//

// class JvmtiRawMonitor

//

// Used by JVMTI methods: All RawMonitor methods (CreateRawMonitor, EnterRawMonitor, etc.)

//

// A simplified version of the ObjectMonitor code.

//

class JvmtiRawMonitor : public CHeapObj<mtSynchronizer>  {

  // Helper class to allow Threads to be linked into queues.

  // This is a stripped down version of ObjectWaiter.

  class QNode : public StackObj {

    friend class JvmtiRawMonitor;

    enum TStates { TS_READY, TS_RUN, TS_WAIT, TS_ENTER };

    QNode* volatile _next;

    QNode* volatile _prev;

    ParkEvent* _event;

    volatile int _notified;

    volatile TStates _t_state;

    QNode(Thread* thread);

  };

  Thread* volatile _owner;      // pointer to owning thread

  volatile int _recursions;     // recursion count, 0 for first entry

  QNode* volatile _entry_list;  // Threads blocked on entry or reentry.

                                // The list is actually composed of nodes,

                                // acting as proxies for Threads.

  QNode* volatile _wait_set;    // Threads wait()ing on the monitor

  volatile jint _waiters;       // number of waiting threads

  int _magic;

  char* _name;

  // JVMTI_RM_MAGIC is set in contructor and unset in destructor.

  enum { JVMTI_RM_MAGIC = (int)(('T' << 24) | ('I' << 16) | ('R' << 8) | 'M') };

  void simple_enter(Thread* self);

  void simple_exit(Thread* self);

  int simple_wait(Thread* self, jlong millis);

  void simple_notify(Thread* self, bool all);

 public:

  // return codes

  enum {

    M_OK,                    // no error

    M_ILLEGAL_MONITOR_STATE, // IllegalMonitorStateException

    M_INTERRUPTED            // Thread.interrupt()

  };

  // Non-aborting operator new

  void* operator new(size_t size) throw() {

    return CHeapObj::operator new(size, std::nothrow);

  }

  JvmtiRawMonitor(const char* name);

  ~JvmtiRawMonitor();

  Thread* owner() const { return _owner; }

  void set_owner(Thread* owner) { _owner = owner; }

  int recursions() const { return _recursions; }

  void raw_enter(Thread* self);

  int raw_exit(Thread* self);

  int raw_notify(Thread* self);

  int raw_notifyAll(Thread* self);

  int magic() const { return _magic; }

  const char* get_name() const { return _name; }

  bool is_valid();

};

// Onload pending raw monitors

// Class is used to cache onload or onstart monitor enter

// which will transition into real monitor when

// VM is fully initialized.

class JvmtiPendingMonitors : public AllStatic {

 private:

  static GrowableArray<JvmtiRawMonitor*>* _monitors; // Cache raw monitor enter

  inline static GrowableArray<JvmtiRawMonitor*>* monitors() { return _monitors; }

  static void dispose() {

    delete monitors();

  }

 public:

  static void enter(JvmtiRawMonitor* monitor) {

    monitors()->append(monitor);

  }

  static int count() {

    return monitors()->length();

  }

  static void destroy(JvmtiRawMonitor* monitor) {

    while (monitors()->contains(monitor)) {

      monitors()->remove(monitor);

    }

  }

  // Return false if monitor is not found in the list.

  static bool exit(JvmtiRawMonitor* monitor) {

    if (monitors()->contains(monitor)) {

      monitors()->remove(monitor);

      return true;

    } else {

      return false;

    }

  }

  static void transition_raw_monitors();

};

#endif // SHARE_PRIMS_JVMTIRAWMONITOR_HPP