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   1 /* -*-c-*-
   2  *
   3  * $Id: mprand.h,v 1.1 1999/12/10 23:23:05 mdw Exp $
   4  *
   5  * Generate a random multiprecision integer
   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 /*----- Revision history --------------------------------------------------*
  31  *
  32  * $Log: mprand.h,v $
  33  * Revision 1.1  1999/12/10 23:23:05  mdw
  34  * Support for generating random large integers.
  35  *
  36  */
  37
  38 #ifndef CATACOMB_MPRAND_H
  39 #define CATACOMB_MPRAND_H
  40
  41 #ifdef __cplusplus
  42   extern "C" {
  43 #endif
  44
  45 /*----- Header files ------------------------------------------------------*/
  46
  47 #ifndef CATACOMB_GRAND_H
  48 #  include "grand.h"
  49 #endif
  50
  51 #ifndef CATACOMB_MP_H
  52 #  include "mp.h"
  53 #endif
  54
  55 /*----- Functions provided ------------------------------------------------*/
  56
  57 /* --- @mprand@ --- *
  58  *
  59  * Arguments:   @mp *d@ = destination integer
  60  *              @unsigned b@ = number of bits
  61  *              @grand *r@ = pointer to random number source
  62  *              @mpw or@ = mask to OR with low-order bits
  63  *
  64  * Returns:     A random integer with the requested number of bits
  65  *
  66  * Use:         Constructs an arbitrarily large pseudorandom integer.
  67  *              Assuming that the generator @r@ is good, the result is
  68  *              uniformly distributed in the interval %$[2^{b - 1}, 2^b)$%.
  69  *              The result is then ORred with the given @or@ value.  This
  70  *              will often be 1, to make the result odd.
  71  */
  72
  73 extern mp *mprand(mp */*d*/, unsigned /*b*/, grand */*r*/, mpw /*or*/);
  74
  75 /*----- That's all, folks -------------------------------------------------*/
  76
  77 #ifdef __cplusplus
  78   }
  79 #endif
  80
  81 #endif