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#include "conf.h"
#include <assert.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "pack.h"
#include "aq.h"
#include "file.h"
#include "mp3.h"
#include "libfec.h"
static void usage(void) {
printf("Usage: libfec-test mp3file\n");
}
#define min(a,b) ((a) < (b) ? (a) : (b))
static void hexdump(unsigned char *data, unsigned long len) {
unsigned long i;
for (i = 0; i < len; i += 16) {
unsigned long j;
fprintf(stderr, "%06lx ", i);
for (j = 0; j < min(len - i, 16); j++)
fprintf(stderr, "%02x ", data[i + j]);
fprintf(stderr, "\n");
}
}
int main(int argc, char *argv[]) {
int retval = EXIT_SUCCESS;
if (argc != 2) {
usage();
return EXIT_FAILURE;
}
int fec_k = 20;
int fec_n = 25;
libfec_init(argv[1], "-");
fec_encode_t *encode = libfec_new_encode(fec_k, fec_n);
assert(encode != NULL);
unsigned char buf[8192];
unsigned int len;
int ret;
while ((len = libfec_read_adu(buf, sizeof(buf))) >= 0) {
ret = libfec_add_adu(encode, len, buf);
assert(ret);
static int adu_cnt = 0;
/* decode */
if (++adu_cnt == fec_k) {
int max_length = libfec_max_length(encode);
unsigned char fec_pkts[fec_n][max_length];
unsigned int lengths[fec_n];
int i;
for (i = 0; i < fec_n; i++) {
lengths[i] = libfec_encode(encode, fec_pkts[i], i, max_length);
// assert(lengths[i] != 0);
}
fec_decode_t *group = libfec_new_group(fec_k, fec_n, max_length);
for (i = 0; i < fec_n; i++) {
libfec_add_pkt(group, i, lengths[i], fec_pkts[i]);
}
for (i = 0; i < fec_k; i++) {
unsigned char buf[8192];
unsigned int len;
len = libfec_decode(group, buf, i, sizeof(buf));
// fprintf(stderr, "decode %d, len %d\n", i, len);
// hexdump(buf, len);
if (len) {
libfec_write_adu(buf, len);
}
}
libfec_delete_group(group);
libfec_delete_encode(encode);
encode = libfec_new_encode(fec_k, fec_n);
assert(encode);
adu_cnt = 0;
}
}
libfec_close();
return retval;
}
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