git.distorted.org.uk Git - u/mdw/catacomb/blob - math/mpw.h

   1 /* -*-c-*-
   2  *
   3  * Very low-level multiprecision definitions
   4  *
   5  * (c) 1999 Straylight/Edgeware
   6  */
   7
   8 /*----- Licensing notice --------------------------------------------------*
   9  *
  10  * This file is part of Catacomb.
  11  *
  12  * Catacomb is free software; you can redistribute it and/or modify
  13  * it under the terms of the GNU Library General Public License as
  14  * published by the Free Software Foundation; either version 2 of the
  15  * License, or (at your option) any later version.
  16  *
  17  * Catacomb is distributed in the hope that it will be useful,
  18  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  19  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  20  * GNU Library General Public License for more details.
  21  *
  22  * You should have received a copy of the GNU Library General Public
  23  * License along with Catacomb; if not, write to the Free
  24  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
  25  * MA 02111-1307, USA.
  26  */
  27
  28 #ifndef CATACOMB_MPW_H
  29 #define CATACOMB_MPW_H
  30
  31 #ifdef __cplusplus
  32   extern "C" {
  33 #endif
  34
  35 /*----- Header files ------------------------------------------------------*/
  36
  37 #ifndef CATACOMB_BITS_H
  38 #  include <mLib/bits.h>
  39 #endif
  40
  41 #ifndef CATACOMB_MPTYPES_H
  42 #  include "mptypes.h"
  43 #endif
  44
  45 /*----- Useful macros -----------------------------------------------------*/
  46
  47 /* --- @MPW@ --- *
  48  *
  49  * Arguments:   @x@ = an unsigned value
  50  *
  51  * Use:         Expands to the value of @x@ masked and typecast to a
  52  *              multiprecision integer word.
  53  */
  54
  55 #define MPW(x) ((mpw)((x) & MPW_MAX))
  56
  57 /* --- @MPWS@ --- *
  58  *
  59  * Arguments:   @n@ = number of words
  60  *
  61  * Use:         Expands to the number of bytes occupied by a given number of
  62  *              words.
  63  */
  64
  65 #define MPWS(n) ((n) * sizeof(mpw))
  66
  67 /* --- @MPW_RQ@ --- *
  68  *
  69  * Arguments:   @sz@ = size of an octet array, in octets
  70  *
  71  * Use:         Expands to the number of @mpw@ words required to represent
  72  *              the number held in the octet array.
  73  */
  74
  75 #define MPW_RQ(sz) (((sz) * 8 + MPW_BITS - 1) / MPW_BITS)
  76
  77 /*----- That's all, folks -------------------------------------------------*/
  78
  79 #ifdef __cplusplus
  80   }
  81 #endif
  82
  83 #endif