divmod_1.c

a very popular packet of cryptography tools,it encloses the most common used algorithm and protocols

/*
Copyright 1996, 1998, 2000, 2001 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 Lesser General Public License as published by
the Free Software Foundation; either version 2.1 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 Lesser General Public
License for more details.

You should have received a copy of the GNU Lesser 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 <stdio.h>
#include "gmp.h"
#include "gmp-impl.h"

#if defined (USG) || defined (__SVR4) || defined (_UNICOS) || defined (__hpux)
#include <time.h>

int
cputime ()
{
  if (CLOCKS_PER_SEC < 100000)
    return clock () * 1000 / CLOCKS_PER_SEC;
  return clock () / (CLOCKS_PER_SEC / 1000);
}
#else
#include <sys/types.h>
#include <sys/time.h>
#include <sys/resource.h>

int
cputime ()
{
  struct rusage rus;

  getrusage (0, &rus);
  return rus.ru_utime.tv_sec * 1000 + rus.ru_utime.tv_usec / 1000;
}
#endif

#define M * 1000000

#ifndef CLOCK
#if defined (__m88k__)
#define CLOCK 20 M
#elif defined (__i386__)
#define CLOCK (16666667)
#elif defined (__m68k__)
#define CLOCK (20 M)
#elif defined (_IBMR2)
#define CLOCK (25 M)
#elif defined (__sparc__)
#define CLOCK (20 M)
#elif defined (__sun__)
#define CLOCK (20 M)
#elif defined (__mips)
#define CLOCK (40 M)
#elif defined (__hppa__)
#define CLOCK (50 M)
#elif defined (__alpha)
#define CLOCK (133 M)
#else
#error "Don't know CLOCK of your machine"
#endif
#endif

#ifndef OPS
#define OPS 20000000
#endif
#ifndef SIZE
#define SIZE 1000
#endif
#ifndef TIMES
#define TIMES OPS/SIZE
#else
#undef OPS
#define OPS (SIZE*TIMES)
#endif

main ()
{
  mp_limb_t nptr[SIZE];
  mp_limb_t qptr[SIZE];
  mp_limb_t pptr[SIZE];
  mp_limb_t dlimb, rlimb, plimb;
  mp_size_t nsize, qsize, psize;
  int test;

  for (test = 0; ; test++)
    {
#ifdef RANDOM
      nsize = random () % SIZE + 1;
#else
      nsize = SIZE;
#endif

      mpn_random2 (nptr, nsize);

      mpn_random2 (&dlimb, 1);
      if (dlimb == 0)
	abort ();

      rlimb = mpn_divmod_1 (qptr, nptr, nsize, dlimb);
      qsize = nsize - (qptr[nsize - 1] == 0);
      if (qsize == 0)
	{
	  plimb = rlimb;
	  psize = qsize;
	}
      else
	{
	  plimb = mpn_mul_1 (pptr, qptr, qsize, dlimb);
	  psize = qsize;
	  plimb += mpn_add_1 (pptr, pptr, psize, rlimb);
	}
      if (plimb != 0)
	pptr[psize++] = plimb;


      if (nsize != psize || mpn_cmp (nptr, pptr, nsize) != 0)
	abort ();
    }
}