xref: /isa-l/erasure_code/erasure_code_base_test.c (revision 300260a4d902423a8a69f0f7d74e6abaa33ded27)

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#include <stdio.h>
#include <stdlib.h>
#include <string.h> // for memset, memcmp
#include <assert.h>
#include "erasure_code.h"
#include "test.h"

#define TEST_LEN  8192
#define TEST_SIZE (TEST_LEN / 2)

#ifndef TEST_SOURCES
#define TEST_SOURCES 127
#endif
#ifndef RANDOMS
#define RANDOMS 50
#endif

#define MMAX TEST_SOURCES
#define KMAX TEST_SOURCES

#define EFENCE_TEST_MIN_SIZE 16

#ifdef EC_ALIGNED_ADDR
// Define power of 2 range to check ptr, len alignment
#define PTR_ALIGN_CHK_B 0
#define LEN_ALIGN_CHK_B 0 // 0 for aligned only
#else
// Define power of 2 range to check ptr, len alignment
#define PTR_ALIGN_CHK_B 32
#define LEN_ALIGN_CHK_B 32 // 0 for aligned only
#endif

#ifndef TEST_SEED
#define TEST_SEED 11
#endif

typedef unsigned char u8;

void
dump(unsigned char *buf, int len)
{
        int i;
        for (i = 0; i < len;) {
                printf(" %2x", 0xff & buf[i++]);
                if (i % 32 == 0)
                        printf("\n");
        }
        printf("\n");
}

void
dump_matrix(unsigned char **s, int k, int m)
{
        int i, j;
        for (i = 0; i < k; i++) {
                for (j = 0; j < m; j++) {
                        printf(" %2x", s[i][j]);
                }
                printf("\n");
        }
        printf("\n");
}

void
dump_u8xu8(unsigned char *s, int k, int m)
{
        int i, j;
        for (i = 0; i < k; i++) {
                for (j = 0; j < m; j++) {
                        printf(" %2x", 0xff & s[j + (i * m)]);
                }
                printf("\n");
        }
        printf("\n");
}

// Generate Random errors
static void
gen_err_list(unsigned char *src_err_list, unsigned char *src_in_err, int *pnerrs, int *pnsrcerrs,
             int k, int m)
{
        int i, err;
        int nerrs = 0, nsrcerrs = 0;

        for (i = 0, nerrs = 0, nsrcerrs = 0; i < m && nerrs < m - k; i++) {
                err = 1 & rand();
                src_in_err[i] = err;
                if (err) {
                        src_err_list[nerrs++] = i;
                        if (i < k) {
                                nsrcerrs++;
                        }
                }
        }
        if (nerrs == 0) { // should have at least one error
                while ((err = (rand() % KMAX)) >= m)
                        ;
                src_err_list[nerrs++] = err;
                src_in_err[err] = 1;
                if (err < k)
                        nsrcerrs = 1;
        }
        *pnerrs = nerrs;
        *pnsrcerrs = nsrcerrs;
        return;
}

#define NO_INVERT_MATRIX -2
// Generate decode matrix from encode matrix
static int
gf_gen_decode_matrix(unsigned char *encode_matrix, unsigned char *decode_matrix,
                     unsigned char *invert_matrix, unsigned int *decode_index,
                     unsigned char *src_err_list, unsigned char *src_in_err, int nerrs,
                     int nsrcerrs, int k, int m)
{
        int i, j, p;
        int r;
        unsigned char *backup, *b, s;
        int incr = 0;

        b = malloc(MMAX * KMAX);
        backup = malloc(MMAX * KMAX);

        if (b == NULL || backup == NULL) {
                printf("Test failure! Error with malloc\n");
                free(b);
                free(backup);
                return -1;
        }
        // Construct matrix b by removing error rows
        for (i = 0, r = 0; i < k; i++, r++) {
                while (src_in_err[r])
                        r++;
                for (j = 0; j < k; j++) {
                        b[k * i + j] = encode_matrix[k * r + j];
                        backup[k * i + j] = encode_matrix[k * r + j];
                }
                decode_index[i] = r;
        }
        incr = 0;
        while (gf_invert_matrix(b, invert_matrix, k) < 0) {
                if (nerrs == (m - k)) {
                        free(b);
                        free(backup);
                        printf("BAD MATRIX\n");
                        return NO_INVERT_MATRIX;
                }
                incr++;
                memcpy(b, backup, MMAX * KMAX);
                for (i = nsrcerrs; i < nerrs - nsrcerrs; i++) {
                        if (src_err_list[i] == (decode_index[k - 1] + incr)) {
                                // skip the erased parity line
                                incr++;
                                continue;
                        }
                }
                if (decode_index[k - 1] + incr >= m) {
                        free(b);
                        free(backup);
                        printf("BAD MATRIX\n");
                        return NO_INVERT_MATRIX;
                }
                decode_index[k - 1] += incr;
                for (j = 0; j < k; j++)
                        b[k * (k - 1) + j] = encode_matrix[k * decode_index[k - 1] + j];
        };

        for (i = 0; i < nsrcerrs; i++) {
                for (j = 0; j < k; j++) {
                        decode_matrix[k * i + j] = invert_matrix[k * src_err_list[i] + j];
                }
        }
        /* src_err_list from encode_matrix * invert of b for parity decoding */
        for (p = nsrcerrs; p < nerrs; p++) {
                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 * src_err_list[p] + j]);

                        decode_matrix[k * p + i] = s;
                }
        }
        free(b);
        free(backup);
        return 0;
}

int
main(int argc, char *argv[])
{
        int re = 0;
        int i, j, p, rtest, m, k;
        int nerrs, nsrcerrs;
        void *buf;
        unsigned int decode_index[MMAX];
        unsigned char *temp_buffs[TEST_SOURCES], *buffs[TEST_SOURCES];
        unsigned char *encode_matrix, *decode_matrix, *invert_matrix, *g_tbls;
        unsigned char src_in_err[TEST_SOURCES], src_err_list[TEST_SOURCES];
        unsigned char *recov[TEST_SOURCES];

        int rows, align, size;
        unsigned char *efence_buffs[TEST_SOURCES];
        unsigned int offset;
        u8 *ubuffs[TEST_SOURCES];
        u8 *temp_ubuffs[TEST_SOURCES];

        printf("erasure_code_base_test: %dx%d ", TEST_SOURCES, TEST_LEN);
        srand(TEST_SEED);

        // Allocate the arrays
        for (i = 0; i < TEST_SOURCES; i++) {
                if (posix_memalign(&buf, 64, TEST_LEN)) {
                        printf("alloc error: Fail");
                        return -1;
                }
                buffs[i] = buf;
        }

        for (i = 0; i < TEST_SOURCES; i++) {
                if (posix_memalign(&buf, 64, TEST_LEN)) {
                        printf("alloc error: Fail");
                        return -1;
                }
                temp_buffs[i] = buf;
        }

        // Test erasure code by encode and recovery

        encode_matrix = malloc(MMAX * KMAX);
        decode_matrix = malloc(MMAX * KMAX);
        invert_matrix = malloc(MMAX * KMAX);
        g_tbls = malloc(KMAX * TEST_SOURCES * 32);
        if (encode_matrix == NULL || decode_matrix == NULL || invert_matrix == NULL ||
            g_tbls == NULL) {
                printf("Test failure! Error with malloc\n");
                return -1;
        }
        // Pick a first test
        m = 9;
        k = 5;
        assert((m <= MMAX) && (k <= KMAX));

        // Make random data
        for (i = 0; i < k; i++)
                for (j = 0; j < TEST_LEN; j++)
                        buffs[i][j] = rand();

        // Generate encode matrix encode_matrix
        // The matrix generated by gf_gen_rs_matrix
        // is not always invertable.
        gf_gen_rs_matrix(encode_matrix, m, k);

        // Generate g_tbls from encode matrix encode_matrix
        ec_init_tables_base(k, m - k, &encode_matrix[k * k], g_tbls);

        // Perform matrix dot_prod for EC encoding
        // using g_tbls from encode matrix encode_matrix
        ec_encode_data_base(TEST_LEN, k, m - k, g_tbls, buffs, &buffs[k]);

        // Choose random buffers to be in erasure
        memset(src_in_err, 0, TEST_SOURCES);
        gen_err_list(src_err_list, src_in_err, &nerrs, &nsrcerrs, k, m);

        // Generate decode matrix
        re = gf_gen_decode_matrix(encode_matrix, decode_matrix, invert_matrix, decode_index,
                                  src_err_list, src_in_err, nerrs, nsrcerrs, k, m);
        if (re != 0) {
                printf("Fail to gf_gen_decode_matrix\n");
                return -1;
        }
        // Pack recovery array as list of valid sources
        // Its order must be the same as the order
        // to generate matrix b in gf_gen_decode_matrix
        for (i = 0; i < k; i++) {
                recov[i] = buffs[decode_index[i]];
        }

        // Recover data
        ec_init_tables_base(k, nerrs, decode_matrix, g_tbls);
        ec_encode_data_base(TEST_LEN, k, nerrs, g_tbls, recov, &temp_buffs[k]);
        for (i = 0; i < nerrs; i++) {

                if (0 != memcmp(temp_buffs[k + i], buffs[src_err_list[i]], TEST_LEN)) {
                        printf("Fail error recovery (%d, %d, %d)\n", m, k, nerrs);
                        printf(" - erase list = ");
                        for (j = 0; j < nerrs; j++)
                                printf(" %d", src_err_list[j]);
                        printf(" - Index = ");
                        for (p = 0; p < k; p++)
                                printf(" %d", decode_index[p]);
                        printf("\nencode_matrix:\n");
                        dump_u8xu8((u8 *) encode_matrix, m, k);
                        printf("inv b:\n");
                        dump_u8xu8((u8 *) invert_matrix, k, k);
                        printf("\ndecode_matrix:\n");
                        dump_u8xu8((u8 *) decode_matrix, m, k);
                        printf("recov %d:", src_err_list[i]);
                        dump(temp_buffs[k + i], 25);
                        printf("orig   :");
                        dump(buffs[src_err_list[i]], 25);
                        return -1;
                }
        }

        // Pick a first test
        m = 9;
        k = 5;
        if (m > MMAX || k > KMAX)
                return -1;

        // Make random data
        for (i = 0; i < k; i++)
                for (j = 0; j < TEST_LEN; j++)
                        buffs[i][j] = rand();

        // The matrix generated by gf_gen_cauchy1_matrix
        // is always invertable.
        gf_gen_cauchy1_matrix(encode_matrix, m, k);

        // Generate g_tbls from encode matrix encode_matrix
        ec_init_tables_base(k, m - k, &encode_matrix[k * k], g_tbls);

        // Perform matrix dot_prod for EC encoding
        // using g_tbls from encode matrix encode_matrix
        ec_encode_data_base(TEST_LEN, k, m - k, g_tbls, buffs, &buffs[k]);

        // Choose random buffers to be in erasure
        memset(src_in_err, 0, TEST_SOURCES);
        gen_err_list(src_err_list, src_in_err, &nerrs, &nsrcerrs, k, m);

        // Generate decode matrix
        re = gf_gen_decode_matrix(encode_matrix, decode_matrix, invert_matrix, decode_index,
                                  src_err_list, src_in_err, nerrs, nsrcerrs, k, m);
        if (re != 0) {
                printf("Fail to gf_gen_decode_matrix\n");
                return -1;
        }
        // Pack recovery array as list of valid sources
        // Its order must be the same as the order
        // to generate matrix b in gf_gen_decode_matrix
        for (i = 0; i < k; i++) {
                recov[i] = buffs[decode_index[i]];
        }

        // Recover data
        ec_init_tables_base(k, nerrs, decode_matrix, g_tbls);
        ec_encode_data_base(TEST_LEN, k, nerrs, g_tbls, recov, &temp_buffs[k]);
        for (i = 0; i < nerrs; i++) {

                if (0 != memcmp(temp_buffs[k + i], buffs[src_err_list[i]], TEST_LEN)) {
                        printf("Fail error recovery (%d, %d, %d)\n", m, k, nerrs);
                        printf(" - erase list = ");
                        for (j = 0; j < nerrs; j++)
                                printf(" %d", src_err_list[j]);
                        printf(" - Index = ");
                        for (p = 0; p < k; p++)
                                printf(" %d", decode_index[p]);
                        printf("\nencode_matrix:\n");
                        dump_u8xu8((u8 *) encode_matrix, m, k);
                        printf("inv b:\n");
                        dump_u8xu8((u8 *) invert_matrix, k, k);
                        printf("\ndecode_matrix:\n");
                        dump_u8xu8((u8 *) decode_matrix, m, k);
                        printf("recov %d:", src_err_list[i]);
                        dump(temp_buffs[k + i], 25);
                        printf("orig   :");
                        dump(buffs[src_err_list[i]], 25);
                        return -1;
                }
        }

        // Do more random tests
        for (rtest = 0; rtest < RANDOMS; rtest++) {
                while ((m = (rand() % MMAX)) < 2)
                        ;
                while ((k = (rand() % KMAX)) >= m || k < 1)
                        ;

                if (m > MMAX || k > KMAX)
                        continue;

                // Make random data
                for (i = 0; i < k; i++)
                        for (j = 0; j < TEST_LEN; j++)
                                buffs[i][j] = rand();

                // The matrix generated by gf_gen_cauchy1_matrix
                // is always invertable.
                gf_gen_cauchy1_matrix(encode_matrix, m, k);

                // Make parity vects
                // Generate g_tbls from encode matrix a
                ec_init_tables_base(k, m - k, &encode_matrix[k * k], g_tbls);
                // Perform matrix dot_prod for EC encoding
                // using g_tbls from encode matrix a
                ec_encode_data_base(TEST_LEN, k, m - k, g_tbls, buffs, &buffs[k]);

                // Random errors
                memset(src_in_err, 0, TEST_SOURCES);
                gen_err_list(src_err_list, src_in_err, &nerrs, &nsrcerrs, k, m);

                // Generate decode matrix
                re = gf_gen_decode_matrix(encode_matrix, decode_matrix, invert_matrix, decode_index,
                                          src_err_list, src_in_err, nerrs, nsrcerrs, k, m);
                if (re != 0) {
                        printf("Fail to gf_gen_decode_matrix\n");
                        return -1;
                }
                // Pack recovery array as list of valid sources
                // Its order must be the same as the order
                // to generate matrix b in gf_gen_decode_matrix
                for (i = 0; i < k; i++) {
                        recov[i] = buffs[decode_index[i]];
                }

                // Recover data
                ec_init_tables_base(k, nerrs, decode_matrix, g_tbls);
                ec_encode_data_base(TEST_LEN, k, nerrs, g_tbls, recov, &temp_buffs[k]);

                for (i = 0; i < nerrs; i++) {

                        if (0 != memcmp(temp_buffs[k + i], buffs[src_err_list[i]], TEST_LEN)) {
                                printf("Fail error recovery (%d, %d, %d) - ", m, k, nerrs);
                                printf(" - erase list = ");
                                for (j = 0; j < nerrs; j++)
                                        printf(" %d", src_err_list[j]);
                                printf(" - Index = ");
                                for (p = 0; p < k; p++)
                                        printf(" %d", decode_index[p]);
                                printf("\nencode_matrix:\n");
                                dump_u8xu8((u8 *) encode_matrix, m, k);
                                printf("inv b:\n");
                                dump_u8xu8((u8 *) invert_matrix, k, k);
                                printf("\ndecode_matrix:\n");
                                dump_u8xu8((u8 *) decode_matrix, m, k);
                                printf("orig data:\n");
                                dump_matrix(buffs, m, 25);
                                printf("orig   :");
                                dump(buffs[src_err_list[i]], 25);
                                printf("recov %d:", src_err_list[i]);
                                dump(temp_buffs[k + i], 25);
                                return -1;
                        }
                }
#ifdef TEST_VERBOSE
                putchar('.');
#endif
        }

        // Run tests at end of buffer for Electric Fence
        k = 16;
        align = (LEN_ALIGN_CHK_B != 0) ? 1 : 16;
        if (k > KMAX)
                return -1;

        for (rows = 1; rows <= 16; rows++) {
                m = k + rows;
                if (m > MMAX)
                        return -1;

                // Make random data
                for (i = 0; i < k; i++)
                        for (j = 0; j < TEST_LEN; j++)
                                buffs[i][j] = rand();

                for (size = EFENCE_TEST_MIN_SIZE; size <= TEST_SIZE; size += align) {
                        for (i = 0; i < m; i++) { // Line up TEST_SIZE from end
                                efence_buffs[i] = buffs[i] + TEST_LEN - size;
                        }

                        // The matrix generated by gf_gen_cauchy1_matrix
                        // is always invertable.
                        gf_gen_cauchy1_matrix(encode_matrix, m, k);

                        // Make parity vects
                        // Generate g_tbls from encode matrix a
                        ec_init_tables_base(k, m - k, &encode_matrix[k * k], g_tbls);
                        // Perform matrix dot_prod for EC encoding
                        // using g_tbls from encode matrix a
                        ec_encode_data_base(size, k, m - k, g_tbls, efence_buffs, &efence_buffs[k]);

                        // Random errors
                        memset(src_in_err, 0, TEST_SOURCES);
                        gen_err_list(src_err_list, src_in_err, &nerrs, &nsrcerrs, k, m);

                        // Generate decode matrix
                        re = gf_gen_decode_matrix(encode_matrix, decode_matrix, invert_matrix,
                                                  decode_index, src_err_list, src_in_err, nerrs,
                                                  nsrcerrs, k, m);
                        if (re != 0) {
                                printf("Fail to gf_gen_decode_matrix\n");
                                return -1;
                        }
                        // Pack recovery array as list of valid sources
                        // Its order must be the same as the order
                        // to generate matrix b in gf_gen_decode_matrix
                        for (i = 0; i < k; i++) {
                                recov[i] = efence_buffs[decode_index[i]];
                        }

                        // Recover data
                        ec_init_tables_base(k, nerrs, decode_matrix, g_tbls);
                        ec_encode_data_base(size, k, nerrs, g_tbls, recov, &temp_buffs[k]);

                        for (i = 0; i < nerrs; i++) {

                                if (0 != memcmp(temp_buffs[k + i], efence_buffs[src_err_list[i]],
                                                size)) {
                                        printf("Efence: Fail error recovery (%d, %d, %d)\n", m, k,
                                               nerrs);

                                        printf("size = %d\n", size);

                                        printf("Test erase list = ");
                                        for (j = 0; j < nerrs; j++)
                                                printf(" %d", src_err_list[j]);
                                        printf(" - Index = ");
                                        for (p = 0; p < k; p++)
                                                printf(" %d", decode_index[p]);
                                        printf("\nencode_matrix:\n");
                                        dump_u8xu8((u8 *) encode_matrix, m, k);
                                        printf("inv b:\n");
                                        dump_u8xu8((u8 *) invert_matrix, k, k);
                                        printf("\ndecode_matrix:\n");
                                        dump_u8xu8((u8 *) decode_matrix, m, k);

                                        printf("recov %d:", src_err_list[i]);
                                        dump(temp_buffs[k + i], align);
                                        printf("orig   :");
                                        dump(efence_buffs[src_err_list[i]], align);
                                        return -1;
                                }
                        }
                }
        }

        // Test rand ptr alignment if available

        for (rtest = 0; rtest < RANDOMS; rtest++) {
                while ((m = (rand() % MMAX)) < 2)
                        ;
                while ((k = (rand() % KMAX)) >= m || k < 1)
                        ;

                if (m > MMAX || k > KMAX)
                        continue;

                size = (TEST_LEN - PTR_ALIGN_CHK_B) & ~15;

                offset = (PTR_ALIGN_CHK_B != 0) ? 1 : PTR_ALIGN_CHK_B;
                // Add random offsets
                for (i = 0; i < m; i++) {
                        memset(buffs[i], 0, TEST_LEN);      // zero pad to check write-over
                        memset(temp_buffs[i], 0, TEST_LEN); // zero pad to check write-over
                        ubuffs[i] = buffs[i] + (rand() & (PTR_ALIGN_CHK_B - offset));
                        temp_ubuffs[i] = temp_buffs[i] + (rand() & (PTR_ALIGN_CHK_B - offset));
                }

                for (i = 0; i < k; i++)
                        for (j = 0; j < size; j++)
                                ubuffs[i][j] = rand();

                // The matrix generated by gf_gen_cauchy1_matrix
                // is always invertable.
                gf_gen_cauchy1_matrix(encode_matrix, m, k);

                // Make parity vects
                // Generate g_tbls from encode matrix a
                ec_init_tables_base(k, m - k, &encode_matrix[k * k], g_tbls);
                // Perform matrix dot_prod for EC encoding
                // using g_tbls from encode matrix a
                ec_encode_data_base(size, k, m - k, g_tbls, ubuffs, &ubuffs[k]);

                // Random errors
                memset(src_in_err, 0, TEST_SOURCES);
                gen_err_list(src_err_list, src_in_err, &nerrs, &nsrcerrs, k, m);

                // Generate decode matrix
                re = gf_gen_decode_matrix(encode_matrix, decode_matrix, invert_matrix, decode_index,
                                          src_err_list, src_in_err, nerrs, nsrcerrs, k, m);
                if (re != 0) {
                        printf("Fail to gf_gen_decode_matrix\n");
                        return -1;
                }
                // Pack recovery array as list of valid sources
                // Its order must be the same as the order
                // to generate matrix b in gf_gen_decode_matrix
                for (i = 0; i < k; i++) {
                        recov[i] = ubuffs[decode_index[i]];
                }

                // Recover data
                ec_init_tables_base(k, nerrs, decode_matrix, g_tbls);
                ec_encode_data_base(size, k, nerrs, g_tbls, recov, &temp_ubuffs[k]);

                for (i = 0; i < nerrs; i++) {

                        if (0 != memcmp(temp_ubuffs[k + i], ubuffs[src_err_list[i]], size)) {
                                printf("Fail error recovery (%d, %d, %d) - ", m, k, nerrs);
                                printf(" - erase list = ");
                                for (j = 0; j < nerrs; j++)
                                        printf(" %d", src_err_list[j]);
                                printf(" - Index = ");
                                for (p = 0; p < k; p++)
                                        printf(" %d", decode_index[p]);
                                printf("\nencode_matrix:\n");
                                dump_u8xu8((unsigned char *) encode_matrix, m, k);
                                printf("inv b:\n");
                                dump_u8xu8((unsigned char *) invert_matrix, k, k);
                                printf("\ndecode_matrix:\n");
                                dump_u8xu8((unsigned char *) decode_matrix, m, k);
                                printf("orig data:\n");
                                dump_matrix(ubuffs, m, 25);
                                printf("orig   :");
                                dump(ubuffs[src_err_list[i]], 25);
                                printf("recov %d:", src_err_list[i]);
                                dump(temp_ubuffs[k + i], 25);
                                return -1;
                        }
                }

                // Confirm that padding around dests is unchanged
                memset(temp_buffs[0], 0, PTR_ALIGN_CHK_B); // Make reference zero buff

                for (i = 0; i < m; i++) {

                        offset = ubuffs[i] - buffs[i];

                        if (memcmp(buffs[i], temp_buffs[0], offset)) {
                                printf("Fail rand ualign encode pad start\n");
                                return -1;
                        }
                        if (memcmp(buffs[i] + offset + size, temp_buffs[0],
                                   PTR_ALIGN_CHK_B - offset)) {
                                printf("Fail rand ualign encode pad end\n");
                                return -1;
                        }
                }

                for (i = 0; i < nerrs; i++) {

                        offset = temp_ubuffs[k + i] - temp_buffs[k + i];
                        if (memcmp(temp_buffs[k + i], temp_buffs[0], offset)) {
                                printf("Fail rand ualign decode pad start\n");
                                return -1;
                        }
                        if (memcmp(temp_buffs[k + i] + offset + size, temp_buffs[0],
                                   PTR_ALIGN_CHK_B - offset)) {
                                printf("Fail rand ualign decode pad end\n");
                                return -1;
                        }
                }

#ifdef TEST_VERBOSE
                putchar('.');
#endif
        }

        // Test size alignment

        align = (LEN_ALIGN_CHK_B != 0) ? 13 : 16;

        for (size = TEST_LEN; size > 0; size -= align) {
                while ((m = (rand() % MMAX)) < 2)
                        ;
                while ((k = (rand() % KMAX)) >= m || k < 1)
                        ;

                if (m > MMAX || k > KMAX)
                        continue;

                for (i = 0; i < k; i++)
                        for (j = 0; j < size; j++)
                                buffs[i][j] = rand();

                // The matrix generated by gf_gen_cauchy1_matrix
                // is always invertable.
                gf_gen_cauchy1_matrix(encode_matrix, m, k);

                // Make parity vects
                // Generate g_tbls from encode matrix a
                ec_init_tables_base(k, m - k, &encode_matrix[k * k], g_tbls);
                // Perform matrix dot_prod for EC encoding
                // using g_tbls from encode matrix a
                ec_encode_data_base(size, k, m - k, g_tbls, buffs, &buffs[k]);

                // Random errors
                memset(src_in_err, 0, TEST_SOURCES);
                gen_err_list(src_err_list, src_in_err, &nerrs, &nsrcerrs, k, m);
                // Generate decode matrix
                re = gf_gen_decode_matrix(encode_matrix, decode_matrix, invert_matrix, decode_index,
                                          src_err_list, src_in_err, nerrs, nsrcerrs, k, m);
                if (re != 0) {
                        printf("Fail to gf_gen_decode_matrix\n");
                        return -1;
                }
                // Pack recovery array as list of valid sources
                // Its order must be the same as the order
                // to generate matrix b in gf_gen_decode_matrix
                for (i = 0; i < k; i++) {
                        recov[i] = buffs[decode_index[i]];
                }

                // Recover data
                ec_init_tables_base(k, nerrs, decode_matrix, g_tbls);
                ec_encode_data_base(size, k, nerrs, g_tbls, recov, &temp_buffs[k]);

                for (i = 0; i < nerrs; i++) {

                        if (0 != memcmp(temp_buffs[k + i], buffs[src_err_list[i]], size)) {
                                printf("Fail error recovery (%d, %d, %d) - ", m, k, nerrs);
                                printf(" - erase list = ");
                                for (j = 0; j < nerrs; j++)
                                        printf(" %d", src_err_list[j]);
                                printf(" - Index = ");
                                for (p = 0; p < k; p++)
                                        printf(" %d", decode_index[p]);
                                printf("\nencode_matrix:\n");
                                dump_u8xu8((unsigned char *) encode_matrix, m, k);
                                printf("inv b:\n");
                                dump_u8xu8((unsigned char *) invert_matrix, k, k);
                                printf("\ndecode_matrix:\n");
                                dump_u8xu8((unsigned char *) decode_matrix, m, k);
                                printf("orig data:\n");
                                dump_matrix(buffs, m, 25);
                                printf("orig   :");
                                dump(buffs[src_err_list[i]], 25);
                                printf("recov %d:", src_err_list[i]);
                                dump(temp_buffs[k + i], 25);
                                return -1;
                        }
                }
        }

        printf("done EC tests: Pass\n");
        return 0;
}