/* Copyright (c) 2009, 2015, Oracle and/or its affiliates. All rights reserved.

   This program is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; version 2 of the License.

   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 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 SQL_THREAD_INCLUDED
#define SQL_THREAD_INCLUDED

#include <my_global.h>
#include <mysql/psi/mysql_thread.h>

namespace thread {

/*
  An abstract class for creating/running/joining threads.
  Thread::start() will create a new pthread, and execute the run() function.
*/
class Thread
{
public:
  Thread()
  {}
  virtual ~Thread()
  {}

  /*
    Will create a new pthread, and invoke run();
    Returns the value from my_thread_create().
  */
  int start();

  /*
    You may invoke this to wait for the thread to finish.
    You should probalbly join() a thread before deleting it.
  */
  void join();

  // The handle of the thread (valid only if it is actually running).
  my_thread_handle thread_handle() const { return m_thread_handle; }

  /*
    A wrapper for the run() function.
    Users should *not* call this function directly, they should rather
    invoke the start() function.
  */
  static void run_wrapper(Thread*);

protected:
  /*
    Define this function in derived classes.
    Users should *not* call this function directly, they should rather
    invoke the start() function.
  */
  virtual void run() = 0;

private:
  my_thread_handle m_thread_handle;

  Thread(const Thread&);                        /* Not copyable. */
  void operator=(const Thread&);                /* Not assignable. */
};


// A barrier which can be used for one-time synchronization between threads.
class Notification
{
public:
  Notification();
  ~Notification();

  bool has_been_notified();
  void wait_for_notification();
  void notify();
private:
  bool            m_notified;
  mysql_cond_t    m_cond;
  mysql_mutex_t   m_mutex;

  Notification(const Notification&);            /* Not copyable. */
  void operator=(const Notification&);          /* Not assignable. */
};

}  // namespace thread

#endif  // SQL_THREAD_INCLUDED