ceph/src/erasure-code/jerasure/gf-complete/examples/gf_example_5.c

   1 /*
   2  * GF-Complete: A Comprehensive Open Source Library for Galois Field Arithmetic
   3  * James S. Plank, Ethan L. Miller, Kevin M. Greenan,
   4  * Benjamin A. Arnold, John A. Burnum, Adam W. Disney, Allen C. McBride.
   5  *
   6  * gf_example_5.c
   7  *
   8  * Demonstrating altmap and extract_word
   9  */
  10
  11 #include <stdio.h>
  12 #include <getopt.h>
  13 #include <stdint.h>
  14 #include <string.h>
  15 #include <stdlib.h>
  16 #include <time.h>
  17
  18 #include "gf_complete.h"
  19 #include "gf_rand.h"
  20
  21 void usage(char *s)
  22 {
  23   fprintf(stderr, "usage: gf_example_5\n");
  24   exit(1);
  25 }
  26
  27 int main(int argc, char **argv)
  28 {
  29   uint16_t *a, *b;
  30   int i, j;
  31   gf_t gf;
  32
  33   if (gf_init_hard(&gf, 16, GF_MULT_SPLIT_TABLE, GF_REGION_ALTMAP, GF_DIVIDE_DEFAULT,
  34                    0, 16, 4, NULL, NULL) == 0) {
  35     fprintf(stderr, "gf_init_hard failed\n");
  36     exit(1);
  37   }
  38
  39   a = (uint16_t *) malloc(200);
  40   b = (uint16_t *) malloc(200);
  41
  42   a += 6;
  43   b += 6;
  44
  45   MOA_Seed(0);
  46
  47   for (i = 0; i < 30; i++) a[i] = MOA_Random_W(16, 1);
  48
  49   gf.multiply_region.w32(&gf, a, b, 0x1234, 30*2, 0);
  50
  51   printf("a: 0x%lx    b: 0x%lx\n", (unsigned long) a, (unsigned long) b);
  52
  53   for (i = 0; i < 30; i += 10) {
  54     printf("\n");
  55     printf("  ");
  56     for (j = 0; j < 10; j++) printf(" %4d", i+j);
  57     printf("\n");
  58
  59     printf("a:");
  60     for (j = 0; j < 10; j++) printf(" %04x", a[i+j]);
  61     printf("\n");
  62
  63     printf("b:");
  64     for (j = 0; j < 10; j++) printf(" %04x", b[i+j]);
  65     printf("\n");
  66     printf("\n");
  67   }
  68
  69   for (i = 0; i < 15; i ++) {
  70     printf("Word %2d: 0x%04x * 0x1234 = 0x%04x    ", i,
  71            gf.extract_word.w32(&gf, a, 30*2, i),
  72            gf.extract_word.w32(&gf, b, 30*2, i));
  73     printf("Word %2d: 0x%04x * 0x1234 = 0x%04x\n", i+15,
  74            gf.extract_word.w32(&gf, a, 30*2, i+15),
  75            gf.extract_word.w32(&gf, b, 30*2, i+15));
  76   }
  77   return 0;
  78 }