/*! ========================================================================
** Extended Template and Library
** Random Number Generator Class Implementation
** $Id$
**
** Copyright (c) 2002 Robert B. Quattlebaum Jr.
**
** This package 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 package 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.
**
** === N O T E S ===========================================================
**
** This is an internal header file, included by other ETL headers.
** You should not attempt to use it directly.
**
** ========================================================================= */
/* === S T A R T =========================================================== */
#ifndef __ETL__RANDOM_H
#define __ETL__RANDOM_H
/* === H E A D E R S ======================================================= */
/* === M A C R O S ========================================================= */
/* === C L A S S E S & S T R U C T S ======================================= */
_ETL_BEGIN_NAMESPACE
/*
class rand_source_xor
{
public:
typedef int seed_type;
typedef short value_type;
private:
short entropy_pool[256];
int pool_index;
public:
random()
{
seed(0);
mod=offset=0;
}
void seed(const seed_type &x)
{ pool_index=0; }
void add_entropy(value_type entropy)
{
int i;
for(i=0;i<POOL_SIZE;i++)
entropy^=(entropy_pool[i]^=entropy*i);
}
void add_entropy(const value_type *entropy, int size)
{
}
short get_short()
{
if(pool_index>POOL_SIZE)
pool_index=0;
if(mod)
return entropy_pool[pool_index++]%mod+offset;
return entropy_pool[pool_index++];
}
};
*/
template <class T,int POOL_SIZE=256>
class random
{
public:
typedef T value_type;
typedef int seed_type;
private:
value_type entropy_pool[POOL_SIZE];
int pool_index;
value_type mod,offset;
public:
random()
{
seed(0);
mod=offset=0;
}
void seed(const seed_type &x __attribute__ ((unused)))
{ pool_index=0; }
void set_range(const value_type &floor,const value_type &ceil)
{ mod=ceil-floor; offset=floor; }
void set_range(const value_type &ceil)
{ mod=ceil; }
void add_entropy(value_type entropy)
{
int i;
for(i=0;i<POOL_SIZE;i++)
entropy^=(entropy_pool[i]^=entropy*i);
}
void add_entropy(const char *entropy)
{
}
value_type operator()(void)
{
if(pool_index>POOL_SIZE)
pool_index=0;
if(mod)
return entropy_pool[pool_index++]%mod+offset;
return entropy_pool[pool_index++];
}
};
/* === T Y P E D E F S ===================================================== */
_ETL_END_NAMESPACE
/* === E N D =============================================================== */
#endif