/* mpz_mul_ui/si (product, multiplier, small_multiplicand) -- Set PRODUCT to
   MULTIPLICATOR times SMALL_MULTIPLICAND.

Copyright (C) 1991, 1993, 1994, 1996, 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 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 "gmp.h"
#include "gmp-impl.h"


#ifdef OPERATION_mul_ui
#define FUNCTION              mpz_mul_ui
#define MULTIPLICAND_UNSIGNED unsigned
#define MULTIPLICAND_ABS(x)   x
#else
#ifdef OPERATION_mul_si
#define FUNCTION              mpz_mul_si
#define MULTIPLICAND_UNSIGNED
#define MULTIPLICAND_ABS(x)   ABS(x)
#else
Error, error, unrecognised OPERATION
#endif
#endif


void
#if __STDC__
FUNCTION (mpz_ptr prod, mpz_srcptr mult,
          MULTIPLICAND_UNSIGNED long int small_mult)
#else
FUNCTION (prod, mult, small_mult)
     mpz_ptr prod;
     mpz_srcptr mult;
     MULTIPLICAND_UNSIGNED long int small_mult;
#endif
{
  mp_size_t size = mult->_mp_size;
  mp_size_t sign_product = size;
  mp_limb_t cy;
  mp_size_t prod_size;
  mp_ptr prod_ptr;

  if (size == 0 || small_mult == 0)
    {
      prod->_mp_size = 0;
      return;
    }
  size = ABS (size);

  prod_size = size + 1;
  if (prod->_mp_alloc < prod_size)
    _mpz_realloc (prod, prod_size);

  prod_ptr = prod->_mp_d;

  cy = mpn_mul_1 (prod_ptr, mult->_mp_d, size,
                  (mp_limb_t) MULTIPLICAND_ABS (small_mult));
  if (cy != 0)
    {
      prod_ptr[size] = cy;
      size++;
    }

  prod->_mp_size = ((sign_product < 0) ^ (small_mult < 0)) ? -size : size;
}