/**********************************************************************
 *
 *   FreeDoko a Doppelkopf-Game
 *    
 *   Copyright (C) 2001-2005  by Diether Knof and Borg Enders
 *
 *   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; either version 2 of 
 *   the License, or (at your option) any later version.
 *
 *   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 can find this license in the file 'gpl.txt'.
 *
 *   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
 *
 *  Contact:
 *    Diether Knof dknof@gmx.de
 *    Borg Enders  borg@borgsoft.de
 *
 *********************************************************************/


#include "constants.h"

#include <sys/stat.h>

// all things written into this stream are ignored
const Null_Str null_str;

// values for the random function
#define PSEUDO_RAND_A 7200
#define PSEUDO_RAND_C  100
#define PSEUDO_RAND_M (PSEUDO_RAND_MAX + 1)

// variable with the last random value
static unsigned rand_value_p = 0;

/*****************************************************************************
 *
 ** unsigned pseudo_rand_set(unsigned const pseudo_seed)
 *
 ** Parameters:	pseudo_seed - new seed
 *
 ** Result:	random value (the new seed)
 ** 
 ** Version:	0.3.6
 *
 ** Description:	sets the random value to the seed (if it is < PSEUDO_RAND_MAX)
 *
 ****************************************************************************/
unsigned
pseudo_rand_set(unsigned const pseudo_seed)
{
  if (pseudo_seed < PSEUDO_RAND_MAX)
    rand_value_p = pseudo_seed;

  return rand_value_p;
} // unsigned pseudo_rand_set(pseudo_seed)

/*****************************************************************************
 *
 ** unsigned pseudo_rand_next()
 *
 ** Parameters:	None
 *
 ** Result:	next pseudo random value
 ** 
 ** Version:	0.3.6
 *
 ** Description:	Result
 *
 ****************************************************************************/
unsigned
pseudo_rand_next()
{
  rand_value_p = (PSEUDO_RAND_A * (rand_value_p % PSEUDO_RAND_M)
		  + PSEUDO_RAND_C) % PSEUDO_RAND_M;

  return rand_value_p;
} // unsigned pseudo_rand_next()

/**
 **
 ** -> result
 **
 ** @param	x	maximal value
 **
 ** @return	random value in {0, ..., x}
 **
 ** @author	Borg Enders
 ** @author	Diether Knof
 **
 ** @version 0.6.3
 **
 **/
unsigned
RAND(unsigned const x)
{
  return (pseudo_rand_next() % (x + 1));
}

/**
 **
 ** generates an error
 **
 ** @param	error_message	error message
 **
 ** @return	-
 **
 ** @author	Diether Knof
 **
 ** @version 0.6.3
 **
 **/
void
generate_error(string const error_message)
{
  DEBUG_ASSERTION(false, error_message);
  
  return ;
}
