isa-l/examples/ec/ec_simple_example.c
Marcel Cornu 9d99f8215d examples: reformat using new code style
Signed-off-by: Marcel Cornu <marcel.d.cornu@intel.com>
2024-04-22 11:35:03 +02:00

274 lines
10 KiB
C

/**********************************************************************
Copyright(c) 2011-2018 Intel Corporation All rights reserved.
Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions
are met:
* Redistributions of source code must retain the above copyright
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* Redistributions in binary form must reproduce the above copyright
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distribution.
* Neither the name of Intel Corporation nor the names of its
contributors may be used to endorse or promote products derived
from this software without specific prior written permission.
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
"AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
(INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
**********************************************************************/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <getopt.h>
#include "erasure_code.h" // use <isa-l.h> instead when linking against installed
#define MMAX 255
#define KMAX 255
typedef unsigned char u8;
int
usage(void)
{
fprintf(stderr,
"Usage: ec_simple_example [options]\n"
" -h Help\n"
" -k <val> Number of source fragments\n"
" -p <val> Number of parity fragments\n"
" -l <val> Length of fragments\n"
" -e <val> Simulate erasure on frag index val. Zero based. Can be repeated.\n"
" -r <seed> Pick random (k, p) with seed\n");
exit(0);
}
static int
gf_gen_decode_matrix_simple(u8 *encode_matrix, u8 *decode_matrix, u8 *invert_matrix,
u8 *temp_matrix, u8 *decode_index, u8 *frag_err_list, int nerrs, int k,
int m);
int
main(int argc, char *argv[])
{
int i, j, m, c, e, ret;
int k = 10, p = 4, len = 8 * 1024; // Default params
int nerrs = 0;
// Fragment buffer pointers
u8 *frag_ptrs[MMAX];
u8 *recover_srcs[KMAX];
u8 *recover_outp[KMAX];
u8 frag_err_list[MMAX];
// Coefficient matrices
u8 *encode_matrix, *decode_matrix;
u8 *invert_matrix, *temp_matrix;
u8 *g_tbls;
u8 decode_index[MMAX];
if (argc == 1)
for (i = 0; i < p; i++)
frag_err_list[nerrs++] = rand() % (k + p);
while ((c = getopt(argc, argv, "k:p:l:e:r:h")) != -1) {
switch (c) {
case 'k':
k = atoi(optarg);
break;
case 'p':
p = atoi(optarg);
break;
case 'l':
len = atoi(optarg);
if (len < 0)
usage();
break;
case 'e':
e = atoi(optarg);
frag_err_list[nerrs++] = e;
break;
case 'r':
srand(atoi(optarg));
k = (rand() % (MMAX - 1)) + 1; // Pick k {1 to MMAX - 1}
p = (rand() % (MMAX - k)) + 1; // Pick p {1 to MMAX - k}
for (i = 0; i < k + p && nerrs < p; i++)
if (rand() & 1)
frag_err_list[nerrs++] = i;
break;
case 'h':
default:
usage();
break;
}
}
m = k + p;
// Check for valid parameters
if (m > MMAX || k > KMAX || m < 0 || p < 1 || k < 1) {
printf(" Input test parameter error m=%d, k=%d, p=%d, erasures=%d\n", m, k, p,
nerrs);
usage();
}
if (nerrs > p) {
printf(" Number of erasures chosen exceeds power of code erasures=%d p=%d\n", nerrs,
p);
usage();
}
for (i = 0; i < nerrs; i++) {
if (frag_err_list[i] >= m) {
printf(" fragment %d not in range\n", frag_err_list[i]);
usage();
}
}
printf("ec_simple_example:\n");
// Allocate coding matrices
encode_matrix = malloc(m * k);
decode_matrix = malloc(m * k);
invert_matrix = malloc(m * k);
temp_matrix = malloc(m * k);
g_tbls = malloc(k * p * 32);
if (encode_matrix == NULL || decode_matrix == NULL || invert_matrix == NULL ||
temp_matrix == NULL || g_tbls == NULL) {
printf("Test failure! Error with malloc\n");
return -1;
}
// Allocate the src & parity buffers
for (i = 0; i < m; i++) {
if (NULL == (frag_ptrs[i] = malloc(len))) {
printf("alloc error: Fail\n");
return -1;
}
}
// Allocate buffers for recovered data
for (i = 0; i < p; i++) {
if (NULL == (recover_outp[i] = malloc(len))) {
printf("alloc error: Fail\n");
return -1;
}
}
// Fill sources with random data
for (i = 0; i < k; i++)
for (j = 0; j < len; j++)
frag_ptrs[i][j] = rand();
printf(" encode (m,k,p)=(%d,%d,%d) len=%d\n", m, k, p, len);
// Pick an encode matrix. A Cauchy matrix is a good choice as even
// large k are always invertable keeping the recovery rule simple.
gf_gen_cauchy1_matrix(encode_matrix, m, k);
// Initialize g_tbls from encode matrix
ec_init_tables(k, p, &encode_matrix[k * k], g_tbls);
// Generate EC parity blocks from sources
ec_encode_data(len, k, p, g_tbls, frag_ptrs, &frag_ptrs[k]);
if (nerrs <= 0)
return 0;
printf(" recover %d fragments\n", nerrs);
// Find a decode matrix to regenerate all erasures from remaining frags
ret = gf_gen_decode_matrix_simple(encode_matrix, decode_matrix, invert_matrix, temp_matrix,
decode_index, frag_err_list, nerrs, k, m);
if (ret != 0) {
printf("Fail on generate decode matrix\n");
return -1;
}
// Pack recovery array pointers as list of valid fragments
for (i = 0; i < k; i++)
recover_srcs[i] = frag_ptrs[decode_index[i]];
// Recover data
ec_init_tables(k, nerrs, decode_matrix, g_tbls);
ec_encode_data(len, k, nerrs, g_tbls, recover_srcs, recover_outp);
// Check that recovered buffers are the same as original
printf(" check recovery of block {");
for (i = 0; i < nerrs; i++) {
printf(" %d", frag_err_list[i]);
if (memcmp(recover_outp[i], frag_ptrs[frag_err_list[i]], len)) {
printf(" Fail erasure recovery %d, frag %d\n", i, frag_err_list[i]);
return -1;
}
}
printf(" } done all: Pass\n");
return 0;
}
/*
* Generate decode matrix from encode matrix and erasure list
*
*/
static int
gf_gen_decode_matrix_simple(u8 *encode_matrix, u8 *decode_matrix, u8 *invert_matrix,
u8 *temp_matrix, u8 *decode_index, u8 *frag_err_list, int nerrs, int k,
int m)
{
int i, j, p, r;
int nsrcerrs = 0;
u8 s, *b = temp_matrix;
u8 frag_in_err[MMAX];
memset(frag_in_err, 0, sizeof(frag_in_err));
// Order the fragments in erasure for easier sorting
for (i = 0; i < nerrs; i++) {
if (frag_err_list[i] < k)
nsrcerrs++;
frag_in_err[frag_err_list[i]] = 1;
}
// Construct b (matrix that encoded remaining frags) by removing erased rows
for (i = 0, r = 0; i < k; i++, r++) {
while (frag_in_err[r])
r++;
for (j = 0; j < k; j++)
b[k * i + j] = encode_matrix[k * r + j];
decode_index[i] = r;
}
// Invert matrix to get recovery matrix
if (gf_invert_matrix(b, invert_matrix, k) < 0)
return -1;
// Get decode matrix with only wanted recovery rows
for (i = 0; i < nerrs; i++) {
if (frag_err_list[i] < k) // A src err
for (j = 0; j < k; j++)
decode_matrix[k * i + j] = invert_matrix[k * frag_err_list[i] + j];
}
// For non-src (parity) erasures need to multiply encode matrix * invert
for (p = 0; p < nerrs; p++) {
if (frag_err_list[p] >= k) { // A parity err
for (i = 0; i < k; i++) {
s = 0;
for (j = 0; j < k; j++)
s ^= gf_mul(invert_matrix[j * k + i],
encode_matrix[k * frag_err_list[p] + j]);
decode_matrix[k * p + i] = s;
}
}
}
return 0;
}