git.distorted.org.uk Git - u/mdw/catacomb/blob - math/genwheel.c

   1 /* -*-c-*-
   2  *
   3  * Generate a prime-iteration wheel
   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 /*----- Header files ------------------------------------------------------*/
  29
  30 #include <ctype.h>
  31 #include <errno.h>
  32 #include <stdio.h>
  33 #include <stdlib.h>
  34 #include <string.h>
  35
  36 #include <mLib/darray.h>
  37 #include <mLib/dstr.h>
  38 #include <mLib/mdwopt.h>
  39 #include <mLib/quis.h>
  40 #include <mLib/report.h>
  41
  42 /*----- Data structures ---------------------------------------------------*/
  43
  44 DA_DECL(uintv, unsigned int);
  45
  46 /*----- Main code ---------------------------------------------------------*/
  47
  48 static unsigned long gcd(unsigned long a, unsigned long b)
  49 {
  50   int t;
  51   if (!a) return (b);
  52   while (b) { t = a%b; a = b; b = t; }
  53   return (a);
  54 }
  55
  56 int main(int argc, char *argv[])
  57 {
  58   int np = 5;
  59   const char *type = "unsigned char";
  60   const char *source = "wheel.c";
  61   const char *header = "wheel.h";
  62   const char *name = "wheel";
  63   const char *sym = 0;
  64   unsigned long i, n;
  65   unsigned long mod;
  66   int o;
  67   uintv v = DA_INIT;
  68
  69   ego(argv[0]);
  70   for (;;) {
  71     o = getopt(argc, argv, "n:c:h:s:t:i:");
  72     if (o < 0)
  73       break;
  74     switch (o) {
  75       case 'n':
  76         np = atoi(optarg);
  77         break;
  78       case 's':
  79         sym = optarg;
  80         break;
  81       case 'c':
  82         source = optarg;
  83         break;
  84       case 'h':
  85         header = optarg;
  86         break;
  87       case 't':
  88         type = optarg;
  89         break;
  90       case 'i':
  91         name = optarg;
  92         break;
  93       default:
  94         pquis(stderr, "Usage: $ [-n nprimes] [-s source] [-h header]\n");
  95         exit(EXIT_FAILURE);
  96     }
  97   }
  98
  99   for (mod = 1, i = 2, n = 0;
 100        n < np;
 101        i++) {
 102     if (gcd(i, mod) == 1) {
 103       mod *= i;
 104       n++;
 105     }
 106   }
 107
 108   n = 1;
 109   for (i = 2; i < mod; i++) {
 110     if (gcd(mod, i) == 1) {
 111       DA_PUSH(&v, i - n);
 112       n = i;
 113     }
 114   }
 115   DA_PUSH(&v, mod + 1 - n);
 116
 117   {
 118     FILE *fp = fopen(header, "w");
 119     dstr d = DSTR_INIT;
 120     const char *q;
 121     if (!fp)
 122       die(EXIT_FAILURE, "couldn't write `%s': %s", header, strerror(errno));
 123     if (!sym) {
 124       for (q = header; *q; q++) {
 125         int ch = (unsigned char)*q;
 126         if (isalnum(ch))
 127           ch = toupper(ch);
 128         else
 129           ch = '_';
 130         DPUTC(&d, ch);
 131       }
 132       DPUTZ(&d);
 133       sym = d.buf;
 134     }
 135     fprintf(fp, "\
 136 /* -*-c-*-\n\
 137  *\n\
 138  * Wheel for small prime iteration [generated]\n\
 139  */\n\
 140 \n\
 141 #ifndef %s\n\
 142 #define %s\n\
 143 \n\
 144 #define WHEELN %luu\n\
 145 #define WHEELMOD %luu\n\
 146 \n\
 147 extern const %s %s[];\n\
 148 \n\
 149 #endif\n\
 150 ",
 151             sym, sym,
 152             (unsigned long)DA_LEN(&v),
 153             mod,
 154             type, name);
 155     dstr_destroy(&d);
 156     if (fclose(fp) == EOF) {
 157       remove(header);
 158       die(EXIT_FAILURE, "error writing `%s': %s", header, strerror(errno));
 159     }
 160   }
 161
 162   {
 163     FILE *fp = fopen(source, "w");
 164     int i;
 165     if (!fp)
 166       die(EXIT_FAILURE, "couldn't write `%s': %s", source, strerror(errno));
 167     fprintf(fp, "\
 168 /* -*-c-*-\n\
 169  *\n\
 170  * Wheel for small prime iteration [generated]\n\
 171  */\n\
 172 \n\
 173 #include \"%s\"\n\
 174 \n\
 175 const %s %s[] = {",
 176             header, type, name);
 177     for (i = 0; i < DA_LEN(&v); i++) {
 178       if (i % 8 == 0)
 179         fputs("\n  ", fp);
 180       fprintf(fp, "%5u, ", DA(&v)[i]);
 181     }
 182     fputs("\n\
 183 };\n\
 184 ", fp);
 185     if (fclose(fp) == EOF) {
 186       remove(source);
 187       die(EXIT_FAILURE, "error writing `%s': %s", source, strerror(errno));
 188     }
 189   }
 190
 191   return (0);
 192 }
 193
 194 /*----- That's all, folks -------------------------------------------------*/