~drizzle-trunk/drizzle/development

/* Copyright (C) 2007 MySQL AB

   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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA */

/*

  Classes for the thread scheduler

*/

#ifdef USE_PRAGMA_INTERFACE

#pragma interface

#endif

class THD;

/* Functions used when manipulating threads */

class scheduler_functions

{

public:

  uint max_threads;

  bool (*init)(void);

  bool (*init_new_connection_thread)(void);

  void (*add_connection)(THD *thd);

  void (*post_kill_notification)(THD *thd);

  bool (*end_thread)(THD *thd, bool cache_thread);

  void (*end)(void);

  scheduler_functions();

};

enum scheduler_types

{

  SCHEDULER_ONE_THREAD_PER_CONNECTION=0,

  SCHEDULER_NO_THREADS,

  SCHEDULER_POOL_OF_THREADS

};

void one_thread_per_connection_scheduler(scheduler_functions* func);

void one_thread_scheduler(scheduler_functions* func);

#define HAVE_POOL_OF_THREADS 1

struct event;

class thd_scheduler

{

public:

  bool logged_in;

  struct event* io_event;

  LIST list;

  bool thread_attached;  /* Indicates if THD is attached to the OS thread */

#ifndef DBUG_OFF

  char dbug_explain_buf[256];

  void swap_dbug_explain();

#endif

  thd_scheduler();

  ~thd_scheduler();

  bool init(THD* parent_thd);

  bool thread_attach();

  void thread_detach();

};

void pool_of_threads_scheduler(scheduler_functions* func);