ceph/src/erasure-code/jerasure/gf-complete/examples/gf_example_6.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_6.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_6\n");
  24   exit(1);
  25 }
  26
  27 int main(int argc, char **argv)
  28 {
  29   uint32_t *a, *b;
  30   int i, j;
  31   gf_t gf, gf_16;
  32
  33   if (gf_init_hard(&gf_16, 16, GF_MULT_LOG_TABLE, GF_REGION_DEFAULT, GF_DIVIDE_DEFAULT,
  34                    0, 0, 0, NULL, NULL) == 0) {
  35     fprintf(stderr, "gf_init_hard (6) failed\n");
  36     exit(1);
  37   }
  38
  39   if (gf_init_hard(&gf, 32, GF_MULT_COMPOSITE, GF_REGION_ALTMAP, GF_DIVIDE_DEFAULT,
  40                    0, 2, 0, &gf_16, NULL) == 0) {
  41     fprintf(stderr, "gf_init_hard (32) failed\n");
  42     exit(1);
  43   }
  44
  45   a = (uint32_t *) malloc(200);
  46   b = (uint32_t *) malloc(200);
  47
  48   a += 3;
  49   b += 3;
  50
  51   MOA_Seed(0);
  52
  53   for (i = 0; i < 30; i++) a[i] = MOA_Random_W(32, 1);
  54
  55   gf.multiply_region.w32(&gf, a, b, 0x12345678, 30*4, 0);
  56
  57   printf("a: 0x%lx    b: 0x%lx\n", (unsigned long) a, (unsigned long) b);
  58
  59   for (i = 0; i < 30; i += 10) {
  60     printf("\n");
  61     printf("  ");
  62     for (j = 0; j < 10; j++) printf(" %8d", i+j);
  63     printf("\n");
  64
  65     printf("a:");
  66     for (j = 0; j < 10; j++) printf(" %08x", a[i+j]);
  67     printf("\n");
  68
  69     printf("b:");
  70     for (j = 0; j < 10; j++) printf(" %08x", b[i+j]);
  71     printf("\n");
  72     printf("\n");
  73   }
  74
  75   for (i = 0; i < 15; i ++) {
  76     printf("Word %2d: 0x%08x * 0x12345678 = 0x%08x    ", i,
  77            gf.extract_word.w32(&gf, a, 30*4, i),
  78            gf.extract_word.w32(&gf, b, 30*4, i));
  79     printf("Word %2d: 0x%08x * 0x12345678 = 0x%08x\n", i+15,
  80            gf.extract_word.w32(&gf, a, 30*4, i+15),
  81            gf.extract_word.w32(&gf, b, 30*4, i+15));
  82   }
  83   return 0;
  84 }