/*
** mt19937ar.h - MT Random functions
**
** Copyright (C) 1997 - 2016, Makoto Matsumoto and Takuji Nishimura,
** All rights reserved.
**
** Permission is hereby granted, free of charge, to any person obtaining
** a copy of this software and associated documentation files (the
** "Software"), to deal in the Software without restriction, including
** without limitation the rights to use, copy, modify, merge, publish,
** distribute, sublicense, and/or sell copies of the Software, and to
** permit persons to whom the Software is furnished to do so, subject to
** the following conditions:
**
** The above copyright notice and this permission notice shall be
** included in all copies or substantial portions of the Software.
**
** THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
** EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
** MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
** IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
** CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
** TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
** SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
**
** [ MIT license: http://www.opensource.org/licenses/mit-license.php ]
**
** Any feedback is very welcome.
** http://www.math.sci.hiroshima-u.ac.jp/~m-mat/MT/emt.html
** email: m-mat @ math.sci.hiroshima-u.ac.jp (remove space)
** 
** This version is modified by mruby developers. If you see any problem,
** contact us first at https://github.com/mruby/mruby/issues
*/

#define N 624

typedef struct {
  unsigned long mt[N];
  int mti;
  union {
    unsigned long int_;
    double double_;
  } gen;

  mrb_int seed;
  mrb_bool has_seed : 1;
} mt_state;

void mrb_random_init_genrand(mt_state *, unsigned long);
unsigned long mrb_random_genrand_int32(mt_state *);
double mrb_random_genrand_real1(mt_state *t);

/* initializes mt[N] with a seed */
void init_genrand(unsigned long s);

/* initialize by an array with array-length */
/* init_key is the array for initializing keys */
/* key_length is its length */
/* slight change for C++, 2004/2/26 */
void init_by_array(unsigned long init_key[], int key_length);

/* generates a random number on [0,0xffffffff]-interval */
unsigned long genrand_int32(void);

/* generates a random number on [0,0x7fffffff]-interval */
long genrand_int31(void);

/* These real versions are due to Isaku Wada, 2002/01/09 added */
/* generates a random number on [0,1]-real-interval */
double genrand_real1(void);

/* generates a random number on [0,1)-real-interval */
double genrand_real2(void);

/* generates a random number on (0,1)-real-interval */
double genrand_real3(void);

/* generates a random number on [0,1) with 53-bit resolution*/
double genrand_res53(void);
