1 // -*- mode:C++; tab-width:8; c-basic-offset:2; indent-tabs-mode:t -*-
2 // vim: ts=8 sw=2 smarttab
4 * Ceph - scalable distributed file system
6 * Copyright (C) 2014 Fujitsu Laboratories
8 * Author: Takanori Nakao <nakao.takanori@jp.fujitsu.com>
9 * Author: Takeshi Miyamae <miyamae.takeshi@jp.fujitsu.com>
11 * This library is free software; you can redistribute it and/or
12 * modify it under the terms of the GNU Lesser General Public
13 * License as published by the Free Software Foundation; either
14 * version 2.1 of the License, or (at your option) any later version.
22 #include "jerasure/include/galois.h"
24 void print_matrix(int *mat, int dim)
28 for (i=0; i<dim; i++) {
29 for (j=0; j<dim; j++) {
30 printf("%d ", mat[i*dim+j]);
36 int calc_determinant(int *matrix, int dim)
38 int i, j, k, *mat, det = 1, coeff_1, coeff_2, *row;
40 // print_matrix(matrix, dim);
42 mat = (int *)malloc(sizeof(int)*dim*dim);
44 printf("mat malloc err\n");
47 memcpy((int *)mat, (int *)matrix, sizeof(int)*dim*dim);
49 row = (int *)malloc(sizeof(int)*dim);
51 printf("row malloc err\n");
55 for (i=0; i<dim; i++) {
56 if (mat[i*dim+i] == 0) {
57 for (k=i+1; k<dim; k++) {
58 if (mat[k*dim+i] != 0) {
59 memcpy((int *)row, (int *)&mat[k*dim], sizeof(int)*dim);
60 memcpy((int *)&mat[k*dim], (int *)&mat[i*dim], sizeof(int)*dim);
61 memcpy((int *)&mat[i*dim], (int *)row, sizeof(int)*dim);
70 coeff_1 = mat[i*dim+i];
71 for (j=i; j<dim; j++) {
72 mat[i*dim+j] = galois_single_divide(mat[i*dim+j], coeff_1, 8);
74 for (k=i+1; k<dim; k++) {
75 if (mat[k*dim+i] != 0) {
76 coeff_2 = mat[k*dim+i];
77 for (j=i; j<dim; j++) {
78 mat[k*dim+j] = mat[k*dim+j] ^ galois_single_multiply(mat[i*dim+j], coeff_2, 8);
82 det = galois_single_multiply(det, coeff_1, 8);
84 // print_matrix(mat, dim);