ceph/src/erasure-code/jerasure/jerasure/Examples/jerasure_01.c

   1 /* *
   2  * Copyright (c) 2014, James S. Plank and Kevin Greenan
   3  * All rights reserved.
   4  *
   5  * Jerasure - A C/C++ Library for a Variety of Reed-Solomon and RAID-6 Erasure
   6  * Coding Techniques
   7  *
   8  * Revision 2.0: Galois Field backend now links to GF-Complete
   9  *
  10  * Redistribution and use in source and binary forms, with or without
  11  * modification, are permitted provided that the following conditions
  12  * are met:
  13  *
  14  *  - Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  *
  17  *  - Redistributions in binary form must reproduce the above copyright
  18  *    notice, this list of conditions and the following disclaimer in
  19  *    the documentation and/or other materials provided with the
  20  *    distribution.
  21  *
  22  *  - Neither the name of the University of Tennessee nor the names of its
  23  *    contributors may be used to endorse or promote products derived
  24  *    from this software without specific prior written permission.
  25  *
  26  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  27  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  28  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  29  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  30  * HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
  31  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
  32  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
  33  * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
  34  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  35  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY
  36  * WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  37  * POSSIBILITY OF SUCH DAMAGE.
  38  */
  39
  40 /* Jerasure's authors:
  41
  42    Revision 2.x - 2014: James S. Plank and Kevin M. Greenan.
  43    Revision 1.2 - 2008: James S. Plank, Scott Simmerman and Catherine D. Schuman.
  44    Revision 1.0 - 2007: James S. Plank.
  45  */
  46
  47 #include <stdio.h>
  48 #include <stdlib.h>
  49 #include "jerasure.h"
  50
  51 #define talloc(type, num) (type *) malloc(sizeof(type)*(num))
  52
  53 usage(char *s)
  54 {
  55   fprintf(stderr, "usage: jerasure_01 r c w - creates and prints out a matrix in GF(2^w).\n\n");
  56   fprintf(stderr, "       Element i,j is equal to 2^(i*c+j)\n");
  57   fprintf(stderr, "       \n");
  58   fprintf(stderr, "This demonstrates jerasure_print_matrix().\n");
  59   if (s != NULL) fprintf(stderr, "%s\n", s);
  60   exit(1);
  61 }
  62
  63 int main(int argc, char **argv)
  64 {
  65   int r, c, w, i, n;
  66   int *matrix;
  67
  68   if (argc != 4) usage(NULL);
  69   if (sscanf(argv[1], "%d", &r) == 0 || r <= 0) usage("Bad r");
  70   if (sscanf(argv[2], "%d", &c) == 0 || c <= 0) usage("Bad c");
  71   if (sscanf(argv[3], "%d", &w) == 0 || w <= 0) usage("Bad w");
  72
  73   matrix = talloc(int, r*c);
  74
  75   n = 1;
  76   for (i = 0; i < r*c; i++) {
  77     matrix[i] = n;
  78     n = galois_single_multiply(n, 2, w);
  79   }
  80
  81   printf("<HTML><TITLE>jerasure_01");
  82   for (i = 1; i < argc; i++) printf(" %s", argv[i]);
  83   printf("</TITLE>\n");
  84   printf("<h3>jerasure_01");
  85   for (i = 1; i < argc; i++) printf(" %s", argv[i]);
  86   printf("</h3>\n");
  87   printf("<pre>\n");
  88
  89   jerasure_print_matrix(matrix, r, c, w);
  90   return 0;
  91 }
  92