/* test mpz_divisible_p and mpz_divisible_ui_p

Copyright 2001, 2009 Free Software Foundation, Inc.

This file is part of the GNU MP Library test suite.

The GNU MP Library test suite 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 3 of the License,

or (at your option) any later version.

The GNU MP Library test suite 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.

You should have received a copy of the GNU General Public License along with

the GNU MP Library test suite.  If not, see https://www.gnu.org/licenses/.  */

#include <stdio.h>

#include <stdlib.h>

#include "gmp.h"

#include "gmp-impl.h"

#include "tests.h"

void

check_one (mpz_srcptr a, mpz_srcptr d, int want)

{

  int   got;

  if (mpz_fits_ulong_p (d))

    {

      unsigned long  u = mpz_get_ui (d);

      got = (mpz_divisible_ui_p (a, u) != 0);

      if (want != got)

        {

          printf ("mpz_divisible_ui_p wrong\n");

          printf ("   expected %d got %d\n", want, got);

          mpz_trace ("   a", a);

          printf ("   d=%lu\n", u);

          mp_trace_base = -16;

          mpz_trace ("   a", a);

          printf ("   d=0x%lX\n", u);

          abort ();

        }

    }

  got = (mpz_divisible_p (a, d) != 0);

  if (want != got)

    {

      printf ("mpz_divisible_p wrong\n");

      printf ("   expected %d got %d\n", want, got);

      mpz_trace ("   a", a);

      mpz_trace ("   d", d);

      mp_trace_base = -16;

      mpz_trace ("   a", a);

      mpz_trace ("   d", d);

      abort ();

    }

}

void

check_data (void)

{

  static const struct {

    const char *a;

    const char *d;

    int        want;

  } data[] = {

    { "0",    "0", 1 },

    { "17",   "0", 0 },

    { "0",    "1", 1 },

    { "123",  "1", 1 },

    { "-123", "1", 1 },

    { "0",  "2", 1 },

    { "1",  "2", 0 },

    { "2",  "2", 1 },

    { "-2", "2", 1 },

    { "0x100000000000000000000000000000000", "2", 1 },

    { "0x100000000000000000000000000000001", "2", 0 },

    { "0x3333333333333333", "3", 1 },

    { "0x3333333333333332", "3", 0 },

    { "0x33333333333333333333333333333333", "3", 1 },

    { "0x33333333333333333333333333333332", "3", 0 },

    /* divisor changes from 2 to 1 limb after stripping 2s */

    {          "0x3333333300000000",         "0x180000000",         1 },

    {  "0x33333333333333330000000000000000", "0x18000000000000000", 1 },

    { "0x133333333333333330000000000000000", "0x18000000000000000", 0 },

  };

  mpz_t   a, d;

  int     i;

  mpz_init (a);

  mpz_init (d);

  for (i = 0; i < numberof (data); i++)

    {

      mpz_set_str_or_abort (a, data[i].a, 0);

      mpz_set_str_or_abort (d, data[i].d, 0);

      check_one (a, d, data[i].want);

    }

  mpz_clear (a);

  mpz_clear (d);

}

void

check_random (int reps)

{

  gmp_randstate_ptr rands = RANDS;

  mpz_t   a, d, r;

  int     i;

  int     want;

  mpz_init (a);

  mpz_init (d);

  mpz_init (r);

  for (i = 0; i < reps; i++)

    {

      mpz_erandomb (a, rands, 1 << 19);

      mpz_erandomb_nonzero (d, rands, 1 << 18);

      mpz_fdiv_r (r, a, d);

      want = (mpz_sgn (r) == 0);

      check_one (a, d, want);

      mpz_sub (a, a, r);

      check_one (a, d, 1);

      if (mpz_cmpabs_ui (d, 1L) == 0)

        continue;

      mpz_add_ui (a, a, 1L);

      check_one (a, d, 0);

    }

  mpz_clear (a);

  mpz_clear (d);

  mpz_clear (r);

}

int

main (int argc, char *argv[])

{

  int  reps = 100;

  tests_start ();

  if (argc == 2)

    reps = atoi (argv[1]);

  check_data ();

  check_random (reps);

  tests_end ();

  exit (0);

}