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

   1 /* -*-c-*-
   2  *
   3  * $Id: gfx-sqr-mktab.c,v 1.1 2000/10/08 15:49:37 mdw Exp $
   4  *
   5  * Build table for squaring of binary polynomials
   6  *
   7  * (c) 2000 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: gfx-sqr-mktab.c,v $
  33  * Revision 1.1  2000/10/08 15:49:37  mdw
  34  * First glimmerings of binary polynomial arithmetic.
  35  *
  36  */
  37
  38 /*----- Header files ------------------------------------------------------*/
  39
  40 #include <stdio.h>
  41 #include <stdlib.h>
  42
  43 #include <mLib/bits.h>
  44
  45 /*----- Main code ---------------------------------------------------------*/
  46
  47 static void mktab(uint16 *t)
  48 {
  49   unsigned i, j, x;
  50
  51   for (i = 0; i < 256; i++) {
  52     x = 0;
  53     for (j = 0; j < 8; j++) {
  54       if (i & (1 << j))
  55         x |= 1 << (2 * j);
  56     }
  57     t[i] = x;
  58   }
  59 }
  60
  61 int main(void)
  62 {
  63   uint16 t[256];
  64   unsigned i;
  65
  66   mktab(t);
  67 fputs("\
  68 /* -*-c-*-\n\
  69  *\n\
  70  * Bit spacing table for binary polynomial squaring\n\
  71  */\n\
  72 \n\
  73 #ifndef GFX_SQR_TAB_H\n\
  74 #define GFX_SQR_TAB_H\n\
  75 \n\
  76 #define GFX_SQRTAB {                                                    \\\n\
  77   ", stdout);
  78
  79   for (i = 0; i < 256; i++) {
  80     printf("0x%04x", t[i]);
  81     if (i == 255)
  82       puts("    \\\n}\n");
  83     else if (i % 8 == 7)
  84       fputs(",  \\\n  ", stdout);
  85     else
  86       fputs(", ", stdout);
  87   }
  88
  89   fputs("#endif\n", stdout);
  90
  91   if (fclose(stdout)) {
  92     fprintf(stderr, "error writing data\n");
  93     exit(EXIT_FAILURE);
  94   }
  95
  96   return (0);
  97 }
  98
  99 /*----- That's all, folks -------------------------------------------------*/