/* Copyright (c) 2015, 2021, Oracle and/or its affiliates.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License, version 2.0,
   as published by the Free Software Foundation.

   This program is also distributed with certain software (including
   but not limited to OpenSSL) that is licensed under separate terms,
   as designated in a particular file or component or in included license
   documentation.  The authors of MySQL hereby grant you an additional
   permission to link the program and your derivative works with the
   separately licensed software that they have included with MySQL.

   This program 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 2.0, for more details.

   You should have received a copy of the GNU General Public License
   along with this program; if not, write to the Free Software
   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301  USA */

#ifndef MY_XP_MUTEX_INCLUDED
#define MY_XP_MUTEX_INCLUDED

#include <errno.h>
#include <stdlib.h>

#ifdef _WIN32
#include <windows.h>

typedef CRITICAL_SECTION native_mutex_t;
typedef int              native_mutexattr_t;
#else
#include <pthread.h>
#include <stdio.h>

typedef pthread_mutex_t     native_mutex_t;
typedef pthread_mutexattr_t native_mutexattr_t;
#endif

/**
  @class My_xp_mutex

  Abstract class used to wrap mutex for various platforms.

  A typical use case is:

  @code{.cpp}

  My_xp_mutex mutex= new My_xp_mutex_impl();
  mutex->init(NULL);

  mutex->lock();
  ...
  mutex->unlock();

  @endcode
*/
class My_xp_mutex
{
public:
  /**
    Initialize mutex.

    @param mutex attributes reference
    @return success status
  */

  virtual int init(const native_mutexattr_t *attr)= 0;


  /**
    Destroy mutex.

    @return success status
  */

  virtual int destroy()= 0;


  /**
    Lock mutex.

    @return success status
  */

  virtual int lock()= 0;


  /**
    Trylock mutex.

    @return success status
  */

  virtual int trylock()= 0;


  /**
    Unlock mutex.

    @return success status
  */

  virtual int unlock()= 0;


  /**
    To get native mutex reference.

    @return native mutex pointer
  */

  virtual native_mutex_t *get_native_mutex()= 0;


  virtual ~My_xp_mutex() {}
};

#ifdef _WIN32
class My_xp_mutex_win : public My_xp_mutex
{
private:
  /*
    Disabling the copy constructor and assignment operator.
  */
  My_xp_mutex_win(My_xp_mutex_win const&);
  My_xp_mutex_win& operator=(My_xp_mutex_win const&);
public:
  explicit My_xp_mutex_win();
  virtual ~My_xp_mutex_win();
#else
class My_xp_mutex_pthread : public My_xp_mutex
{
private:
  /*
    Disabling the copy constructor and assignment operator.
  */
  My_xp_mutex_pthread(My_xp_mutex_pthread const&);
  My_xp_mutex_pthread& operator=(My_xp_mutex_pthread const&);
public:
  explicit My_xp_mutex_pthread();
  virtual ~My_xp_mutex_pthread();
#endif
  int init(const native_mutexattr_t *attr);
  int destroy();
  int lock();
  int trylock();
  int unlock();
  native_mutex_t *get_native_mutex();

protected:
  native_mutex_t *m_mutex;
};

#ifdef _WIN32
class My_xp_mutex_impl : public My_xp_mutex_win
#else
class My_xp_mutex_impl : public My_xp_mutex_pthread
#endif
{
public:
  explicit My_xp_mutex_impl() {}
  ~My_xp_mutex_impl() {}
};

class My_xp_mutex_util
{
public:
  /**
    Initialize mutex attributes object

    @param mutex attributes reference
    @return success status
  */

  static int attr_init(native_mutexattr_t *attr);


  /**
    Destroy mutex attributes object

    @param mutex attributes reference
    @return success status
  */

  static int attr_destroy(native_mutexattr_t *attr);
};

#endif // MY_XP_MUTEX_INCLUDED
