/*

 * Copyright (c) 1997, 2015, 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_VM_RUNTIME_JAVA_HPP

#define SHARE_VM_RUNTIME_JAVA_HPP

#include "runtime/os.hpp"

// Execute code before all handles are released and thread is killed; prologue to vm_exit

extern void before_exit(JavaThread * thread);

// Forced VM exit (i.e, internal error or JVM_Exit)

extern void vm_exit(int code);

// Wrapper for ::exit()

extern void vm_direct_exit(int code);

// Shutdown the VM but do not exit the process

extern void vm_shutdown();

// Shutdown the VM and abort the process

extern void vm_abort(bool dump_core=true);

// Trigger any necessary notification of the VM being shutdown

extern void notify_vm_shutdown();

// VM exit if error occurs during initialization of VM

extern void vm_exit_during_initialization(Handle exception);

extern void vm_exit_during_initialization(Symbol* exception_name, const char* message);

extern void vm_exit_during_initialization(const char* error, const char* message = NULL);

extern void vm_shutdown_during_initialization(const char* error, const char* message = NULL);

/**

 * Discovering the JDK_Version during initialization is tricky when the

 * running JDK is less than JDK6.  For JDK6 and greater, a "GetVersion"

 * function exists in libjava.so and we simply call it during the

 * 'initialize()' call to find the version.  For JDKs with version < 6, no

 * such call exists and we have to probe the JDK in order to determine

 * the exact version.  This probing cannot happen during late in

 * the VM initialization process so there's a period of time during

 * initialization when we don't know anything about the JDK version other than

 * that it less than version 6.  This is the "partially initialized" time,

 * when we can answer only certain version queries (such as, is the JDK

 * version greater than 5?  Answer: no).  Once the JDK probing occurs, we

 * know the version and are considered fully initialized.

 */

class JDK_Version VALUE_OBJ_CLASS_SPEC {

  friend class VMStructs;

  friend class Universe;

  friend void JDK_Version_init();

 private:

  static JDK_Version _current;

  static const char* _runtime_name;

  static const char* _runtime_version;

  // In this class, we promote the minor version of release to be the

  // major version for releases >= 5 in anticipation of the JDK doing the

  // same thing.  For example, we represent "1.5.0" as major version 5 (we

  // drop the leading 1 and use 5 as the 'major').

  uint8_t _major;

  uint8_t _minor;

  uint8_t _micro;

  uint8_t _update;

  uint8_t _special;

  uint8_t _build;

  // If partially initialized, the above fields are invalid and we know

  // that we're less than major version 6.

  bool _partially_initialized;

  bool _thread_park_blocker;

  bool _post_vm_init_hook_enabled;

  bool is_valid() const {

    return (_major != 0 || _partially_initialized);

  }

  // initializes or partially initializes the _current static field

  static void initialize();

  // Completes initialization for a pre-JDK6 version.

  static void fully_initialize(uint8_t major, uint8_t minor = 0,

                               uint8_t micro = 0, uint8_t update = 0);

 public:

  // Returns true if the the current version has only been partially initialized

  static bool is_partially_initialized() {

    return _current._partially_initialized;

  }

  JDK_Version() : _major(0), _minor(0), _micro(0), _update(0),

                  _special(0), _build(0), _partially_initialized(false),

                  _thread_park_blocker(false), _post_vm_init_hook_enabled(false)

                  {}

  JDK_Version(uint8_t major, uint8_t minor = 0, uint8_t micro = 0,

              uint8_t update = 0, uint8_t special = 0, uint8_t build = 0,

              bool thread_park_blocker = false, bool post_vm_init_hook_enabled = false) :

      _major(major), _minor(minor), _micro(micro), _update(update),

      _special(special), _build(build), _partially_initialized(false),

      _thread_park_blocker(thread_park_blocker),

      _post_vm_init_hook_enabled(post_vm_init_hook_enabled)

      {}

  // Returns the current running JDK version

  static JDK_Version current() { return _current; }

  // Factory methods for convenience

  static JDK_Version jdk(uint8_t m) {

    return JDK_Version(m);

  }

  static JDK_Version jdk_update(uint8_t major, uint8_t update_number) {

    return JDK_Version(major, 0, 0, update_number);

  }

  static JDK_Version undefined() {

    return JDK_Version(0);

  }

  bool is_undefined() const {

    return (_major == 0);

  }

  uint8_t major_version() const          { return _major; }

  uint8_t minor_version() const          { return _minor; }

  uint8_t micro_version() const          { return _micro; }

  uint8_t update_version() const         { return _update; }

  uint8_t special_update_version() const { return _special; }

  uint8_t build_number() const           { return _build; }

  bool supports_thread_park_blocker() const {

    return _thread_park_blocker;

  }

  bool post_vm_init_hook_enabled() const {

    return _post_vm_init_hook_enabled;

  }

  // Performs a full ordering comparison using all fields (update, build, etc.)

  int compare(const JDK_Version& other) const;

  /**

   * Performs comparison using only the major version, returning negative

   * if the major version of 'this' is less than the parameter, 0 if it is

   * equal, and a positive value if it is greater.

   */

  int compare_major(int version) const {

    if (_partially_initialized) {

      if (version >= 6) {

        return -1;

      } else {

        assert(false, "Can't make this comparison during init time");

        return -1; // conservative

      }

    } else {

      return major_version() - version;

    }

  }

  void to_string(char* buffer, size_t buflen) const;

  static const char* runtime_name() {

    return _runtime_name;

  }

  static void set_runtime_name(const char* name) {

    _runtime_name = name;

  }

  static const char* runtime_version() {

    return _runtime_version;

  }

  static void set_runtime_version(const char* version) {

    _runtime_version = version;

  }

};

#endif // SHARE_VM_RUNTIME_JAVA_HPP