/* gmp_randinit_lc_2exp (state, a, c, m2exp) -- Initialize random
   state STATE for a linear congruential generator with multiplier A,
   adder C, and modulus 2 ^ M2EXP.

Copyright (C) 2000  Free Software Foundation, Inc.

This file is part of the GNU MP Library.

The GNU MP Library is free software; you can redistribute it and/or modify
it under the terms of the GNU Library General Public License as published by
the Free Software Foundation; either version 2 of the License, or (at your
option) any later version.

The GNU MP Library 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 Library General Public
License for more details.

You should have received a copy of the GNU Library General Public License
along with the GNU MP Library; see the file COPYING.LIB.  If not, write to
the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
MA 02111-1307, USA. */

#include "gmp.h"
#include "gmp-impl.h"

void
#if __STDC__
gmp_randinit_lc_2exp (gmp_randstate_t rstate,
		      mpz_t a,
		      unsigned long int c,
		      unsigned long int m2exp)
#else
gmp_randinit_lc_2exp (rstate, a, c, m2exp)
     gmp_randstate_t rstate;
     mpz_t a;
     unsigned long int c;
     unsigned long int m2exp;
#endif
{
  mpz_init_set_ui (rstate->seed, 1);
  _mpz_realloc (rstate->seed, m2exp / BITS_PER_MP_LIMB
		+ (m2exp % BITS_PER_MP_LIMB != 0));

  /* Allocate algorithm specific data. */
  rstate->algdata.lc = (__gmp_randata_lc *)
    (*_mp_allocate_func) (sizeof (__gmp_randata_lc));

  mpz_init_set (rstate->algdata.lc->a, a);
  rstate->algdata.lc->c = c;

  /* Cover weird case where m2exp is 0, which means that m is used
     instead of m2exp.  */
  if (m2exp == 0)
    mpz_init_set_ui (rstate->algdata.lc->m, 0);
  rstate->algdata.lc->m2exp = m2exp;

  rstate->alg = GMP_RAND_ALG_LC;
}