git.distorted.org.uk Git - u/mdw/catacomb/blob - math/gfx-sqr-mktab.c

   1 /* -*-c-*-
   2  *
   3  * Build table for squaring of binary polynomials
   4  *
   5  * (c) 2000 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 <stdio.h>
  31 #include <stdlib.h>
  32
  33 #include <mLib/bits.h>
  34
  35 /*----- Main code ---------------------------------------------------------*/
  36
  37 static void mktab(uint16 *t)
  38 {
  39   unsigned i, j, x;
  40
  41   for (i = 0; i < 256; i++) {
  42     x = 0;
  43     for (j = 0; j < 8; j++) {
  44       if (i & (1 << j))
  45         x |= 1 << (2 * j);
  46     }
  47     t[i] = x;
  48   }
  49 }
  50
  51 int main(void)
  52 {
  53   uint16 t[256];
  54   unsigned i;
  55
  56   mktab(t);
  57 fputs("\
  58 /* -*-c-*-\n\
  59  *\n\
  60  * Bit spacing table for binary polynomial squaring\n\
  61  */\n\
  62 \n\
  63 #include <mLib/bits.h>\n\
  64 \n\
  65 const uint16 gfx_sqrtab[256] = {\n\
  66   ", stdout);
  67
  68   for (i = 0; i < 256; i++) {
  69     printf("0x%04x", t[i]);
  70     if (i == 255)
  71       puts("\n};");
  72     else if (i % 8 == 7)
  73       fputs(",\n  ", stdout);
  74     else
  75       fputs(", ", stdout);
  76   }
  77
  78   if (fclose(stdout)) {
  79     fprintf(stderr, "error writing data\n");
  80     exit(EXIT_FAILURE);
  81   }
  82
  83   return (0);
  84 }
  85
  86 /*----- That's all, folks -------------------------------------------------*/