+/*! ========================================================================
+** 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
+