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

   1 /* -*-c-*-
   2  *
   3  * Iterate over small primes efficiently
   4  *
   5  * (c) 2007 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_PRIMEITER_H
  29 #define CATACOMB_PRIMEITER_H
  30
  31 #ifdef __cplusplus
  32   extern "C" {
  33 #endif
  34
  35 /*----- Header files ------------------------------------------------------*/
  36
  37 #ifndef CATACOMB_GRAND_H
  38 #  include "grand.h"
  39 #endif
  40
  41 #ifndef CATACOMB_MP_H
  42 #  include "mp.h"
  43 #endif
  44
  45 /*----- Data structures ---------------------------------------------------*/
  46
  47 typedef struct primeiter {
  48   mpw w;
  49   mp pp;
  50   mp *p;
  51   grand *r;
  52   unsigned mode;
  53   int i;
  54 } primeiter;
  55
  56 enum {
  57   PIMODE_PTAB,
  58   PIMODE_STALL,
  59   PIMODE_WHEEL
  60 };
  61
  62 /*----- Functions provided ------------------------------------------------*/
  63
  64 /* --- @primeiter_create@ --- *
  65  *
  66  * Arguments:   @primeiter *pi@ = pointer to an iterator structure
  67  *              @mp *start@ = where to start
  68  *
  69  * Returns:     ---
  70  *
  71  * Use:         Initializes a prime iterator.  The first output will be the
  72  *              smallest prime not less than @start@.
  73  */
  74
  75 extern void primeiter_create(primeiter */*pi*/, mp */*start*/);
  76
  77 /* --- @primeiter_destroy@ --- *
  78  *
  79  * Arguments:   @primeiter *pi@ = pointer to iterator structure
  80  *
  81  * Returns:     ---
  82  *
  83  * Use:         Frees up an iterator structure when it's no longer wanted.
  84  */
  85
  86 void primeiter_destroy(primeiter */*pi*/);
  87
  88 /* --- @primeiter_next@ --- *
  89  *
  90  * Arguments:   @primeiter *pi@ = pointer to an iterator structure
  91  *              @mp *d@ = fake destination
  92  *
  93  * Returns:     The next prime number from the iterator.
  94  *
  95  * Use:         Returns a new prime number.
  96  */
  97
  98 mp *primeiter_next(primeiter */*pi*/, mp */*d*/);
  99
 100 /*----- That's all, folks -------------------------------------------------*/
 101
 102 #ifdef __cplusplus
 103   }
 104 #endif
 105
 106 #endif