/*
 * Copyright (C) 2008 Search Solution Corporation. All rights reserved by Search Solution. 
 *
 *   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 
 *
 */


/*
 * wait_for_graph.h - Header file for WFG
 *
 */

#ifndef _WAIT_FOR_GRAPH_H_
#define _WAIT_FOR_GRAPH_H_

#ident "$Id$"

#include "thread_impl.h"

typedef enum
{
  WFG_CYCLE_YES_PRUNE,		/* Cycles were found. There may be more not listed */
  WFG_CYCLE_YES,		/* Cycles were found. All the cycles are listed    */
  WFG_CYCLE_NO,			/* There are not cycles                            */
  WFG_CYCLE_ERROR		/* An error was found during the cycle detection   */
} WFG_CYCLE_CASE;

/* structure of cycle which is obtained by wfg_detect_cycle() below */
typedef struct wfg_waiter WFG_WAITER;
struct wfg_waiter
{
  int tran_index;
  int (*cycle_fun) (int tran_index, void *args);
  void *args;			/* Arguments to be passed to cycle_fun */
};

typedef struct wfg_listcycle WFG_CYCLE;
struct wfg_listcycle
{
  int num_trans;		/* # of transactions in the cycle    */
  WFG_WAITER *waiters;		/* Waiters in the cycle              */
  struct wfg_listcycle *next;	/* pointer to next cycle             */
};

extern int wfg_alloc_nodes (THREAD_ENTRY * thread_p, const int num_trans);
extern int wfg_free_nodes (THREAD_ENTRY * thread_p);
extern int wfg_insert_out_edges (THREAD_ENTRY * thread_p,
				 const int wtran_index, int num_holders,
				 const int *htran_indices,
				 int (*cycle_resolution_fn) (int tran_index,
							     void *args),
				 void *args);
extern int wfg_remove_out_edges (THREAD_ENTRY * thread_p,
				 const int waiter_tran_index,
				 const int num_holders,
				 const int *htran_indices_p);
extern int wfg_get_status (int *num_edges_p, int *num_waiters_p);
extern int wfg_detect_cycle (THREAD_ENTRY * thread_p,
			     WFG_CYCLE_CASE * cycle_case,
			     WFG_CYCLE ** list_cycles_p);
extern int wfg_free_cycle (WFG_CYCLE * list_cycles_p);
extern int wfg_is_waiting (THREAD_ENTRY * thread_p, const int tran_index);
extern int wfg_get_tran_entries (THREAD_ENTRY * thread_p,
				 const int tran_index);

/* Transaction group interfaces */
extern int wfg_alloc_tran_group (THREAD_ENTRY * thread_p);
extern int wfg_insert_holder_tran_group (THREAD_ENTRY * thread_p,
					 const int tran_group_index,
					 const int holder_tran_index);
extern int wfg_remove_holder_tran_group (THREAD_ENTRY * thread_p,
					 const int tran_group_index,
					 const int holder_tran_index);
extern int wfg_insert_waiter_tran_group (THREAD_ENTRY * thread_p,
					 const int tran_group_index,
					 const int waiter_tran_index,
					 int (*cycle_resolution_fn) (int
								     tran_index,
								     void
								     *args),
					 void *args);
extern int wfg_remove_waiter_tran_group (THREAD_ENTRY * thread_p,
					 const int tran_group_index,
					 const int waiter_tran_index);
extern int wfg_is_tran_group_waiting (THREAD_ENTRY * thread_p,
				      const int tran_index);

extern int wfg_dump (THREAD_ENTRY * thread_p);

#endif /* _WAIT_FOR_GRAPH_H_ */