/* * libmad - MPEG audio decoder library * Copyright (C) 2000-2004 Underbit Technologies, Inc. * * This program 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 2 of the License, or * (at your option) any later version. * * This program 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 this program; if not, write to the Free Software * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA * * $Id: fixed.c,v 1.13 2004/01/23 09:41:32 rob Exp $ */ # ifdef HAVE_CONFIG_H#  include "config.h"# endif # include "global.h" # include "fixed.h" /* * NAME:	fixed->abs() * DESCRIPTION:	return absolute value of a fixed-point number */mad_fixed_t mad_f_abs(mad_fixed_t x){  return x < 0 ? -x : x;} /* * NAME:	fixed->div() * DESCRIPTION:	perform division using fixed-point math */mad_fixed_t mad_f_div(mad_fixed_t x, mad_fixed_t y){  mad_fixed_t q, r;  unsigned int bits;   q = mad_f_abs(x / y);   if (x < 0) {    x = -x;    y = -y;  }   r = x % y;   if (y < 0) {    x = -x;    y = -y;  }   if (q > mad_f_intpart(MAD_F_MAX) &&      !(q == -mad_f_intpart(MAD_F_MIN) && r == 0 && (x < 0) != (y < 0)))    return 0;   for (bits = MAD_F_FRACBITS; bits && r; --bits) {    q <<= 1, r <<= 1;    if (r >= y)      r -= y, ++q;  }   /* round */  if (2 * r >= y)    ++q;   /* fix sign */  if ((x < 0) != (y < 0))    q = -q;   return q << bits;}