/* Math functions for i387.
   Copyright (C) 1995, 1996, 1997 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by John C. Bowman <bowman@ipp-garching.mpg.de>, 1995.

   The GNU C 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 C 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 C Library; if not, write to the Free
   Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
   Boston, MA 02110-1301, USA.
*/

#include <win32k.h>

/*
 * FIXME! Is there a better algorithm. like FT_MulDiv
 *
 * @implemented
 */
INT APIENTRY EngMulDiv(
	     INT nMultiplicand,
	     INT nMultiplier,
	     INT nDivisor)
{
#if SIZEOF_LONG_LONG >= 8
    long long ret;

    if (!nDivisor) return -1;

    /* We want to deal with a positive divisor to simplify the logic. */
    if (nDivisor < 0)
    {
      nMultiplicand = - nMultiplicand;
      nDivisor = -nDivisor;
    }

    /* If the result is positive, we "add" to round. else, we subtract to round. */
    if ( ( (nMultiplicand <  0) && (nMultiplier <  0) ) ||
	 ( (nMultiplicand >= 0) && (nMultiplier >= 0) ) )
      ret = (((long long)nMultiplicand * nMultiplier) + (nDivisor/2)) / nDivisor;
    else
      ret = (((long long)nMultiplicand * nMultiplier) - (nDivisor/2)) / nDivisor;

    if ((ret > 2147483647) || (ret < -2147483647)) return -1;
    return ret;
#else
    if (!nDivisor) return -1;

    /* We want to deal with a positive divisor to simplify the logic. */
    if (nDivisor < 0)
    {
      nMultiplicand = - nMultiplicand;
      nDivisor = -nDivisor;
    }

    /* If the result is positive, we "add" to round. else, we subtract to round. */
    if ( ( (nMultiplicand <  0) && (nMultiplier <  0) ) ||
	 ( (nMultiplicand >= 0) && (nMultiplier >= 0) ) )
      return ((nMultiplicand * nMultiplier) + (nDivisor/2)) / nDivisor;

    return ((nMultiplicand * nMultiplier) - (nDivisor/2)) / nDivisor;

#endif
}