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

   1 /* -*-c-*-
   2  *
   3  * $Id: mpw.h,v 1.3 2004/04/08 01:36:15 mdw Exp $
   4  *
   5  * Very low-level multiprecision definitions
   6  *
   7  * (c) 1999 Straylight/Edgeware
   8  */
   9
  10 /*----- Licensing notice --------------------------------------------------*
  11  *
  12  * This file is part of Catacomb.
  13  *
  14  * Catacomb is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU Library General Public License as
  16  * published by the Free Software Foundation; either version 2 of the
  17  * License, or (at your option) any later version.
  18  *
  19  * Catacomb is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU Library General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU Library General Public
  25  * License along with Catacomb; if not, write to the Free
  26  * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
  27  * MA 02111-1307, USA.
  28  */
  29
  30 #ifndef CATACOMB_MPW_H
  31 #define CATACOMB_MPW_H
  32
  33 #ifdef __cplusplus
  34   extern "C" {
  35 #endif
  36
  37 /*----- Header files ------------------------------------------------------*/
  38
  39 #ifndef CATACOMB_BITS_H
  40 #  include <mLib/bits.h>
  41 #endif
  42
  43 #ifndef CATACOMB_MPTYPES_H
  44 #  include "mptypes.h"
  45 #endif
  46
  47 /*----- Useful macros -----------------------------------------------------*/
  48
  49 /* --- @MPW@ --- *
  50  *
  51  * Arguments:   @x@ = an unsigned value
  52  *
  53  * Use:         Expands to the value of @x@ masked and typecast to a
  54  *              multiprecision integer word.
  55  */
  56
  57 #define MPW(x) ((mpw)((x) & MPW_MAX))
  58
  59 /* --- @MPWS@ --- *
  60  *
  61  * Arguments:   @n@ = number of words
  62  *
  63  * Use:         Expands to the number of bytes occupied by a given number of
  64  *              words.
  65  */
  66
  67 #define MPWS(n) ((n) * sizeof(mpw))
  68
  69 /* --- @MPW_RQ@ --- *
  70  *
  71  * Arguments:   @sz@ = size of an octet array, in octets
  72  *
  73  * Use:         Expands to the number of @mpw@ words required to represent
  74  *              the number held in the octet array.
  75  */
  76
  77 #define MPW_RQ(sz) (((sz) * 8 + MPW_BITS - 1) / MPW_BITS)
  78
  79 /*----- That's all, folks -------------------------------------------------*/
  80
  81 #ifdef __cplusplus
  82   }
  83 #endif
  84
  85 #endif