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#include <stdint.h>
#include <math.h>
#include <unistd.h>
#include <stdio.h>
#include <string.h>
#include <errno.h>
#include <stdlib.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <sys/fcntl.h>
#include "dsss_demod.h"
void handle_dsss_received(uint8_t data[TRANSMISSION_SYMBOLS]) {
printf("data sequence received: [ ");
for (size_t i=0; i<TRANSMISSION_SYMBOLS; i++) {
printf("%+3d", ((data[i]&1) ? 1 : -1) * (data[i]>>1));
if (i+1 < TRANSMISSION_SYMBOLS)
printf(", ");
}
printf(" ]\n");
}
void print_usage() {
fprintf(stderr, "Usage: dsss_demod_test [test_data.bin] [optional recording channel number]\n");
}
int main(int argc, char **argv) {
if (argc != 2 && argc != 3) {
fprintf(stderr, "Error: Invalid arguments.\n");
print_usage();
return 1;
}
int fd = open(argv[1], O_RDONLY);
struct stat st;
if (fstat(fd, &st)) {
fprintf(stderr, "Error querying test data file size: %s\n", strerror(errno));
return 2;
}
if (st.st_size < 0 || st.st_size > 1000000) {
fprintf(stderr, "Error reading test data: too much test data (size=%zd)\n", st.st_size);
return 2;
}
if (st.st_size % sizeof(float) != 0) {
fprintf(stderr, "Error reading test data: file size is not divisible by %zd (size=%zd)\n", sizeof(float), st.st_size);
return 2;
}
char *buf = malloc(st.st_size);
if (!buf) {
fprintf(stderr, "Error allocating memory");
return 2;
}
int record_channel = -1;
if (argc == 3) {
char *endptr;
record_channel = strtoul(argv[2], &endptr, 10);
if (!endptr || *endptr != '\0') {
fprintf(stderr, "Invalid channel number \"%s\"\n", argv[2]);
return 1;
}
}
if (record_channel != -1)
fprintf(stderr, "Reading %zd samples test data...", st.st_size/sizeof(float));
size_t nread = 0;
while (nread < st.st_size) {
ssize_t rc = read(fd, buf, st.st_size - nread);
if (rc == -EINTR || rc == -EAGAIN)
continue;
if (rc < 0) {
fprintf(stderr, "\nError reading test data: %s\n", strerror(errno));
return 2;
}
if (rc == 0) {
fprintf(stderr, "\nError reading test data: Unexpected end of file\n");
return 2;
}
nread += rc;
}
if (record_channel != -1)
fprintf(stderr, " done.\n");
const size_t n_samples = st.st_size / sizeof(float);
float *buf_f = (float *)buf;
if (record_channel != -1)
fprintf(stderr, "Starting simulation.\n");
struct dsss_demod_state demod;
dsss_demod_init(&demod);
for (size_t i=0; i<n_samples; i++) {
//fprintf(stderr, "Iteration %zd/%zd\n", i, n_samples);
dsss_demod_step(&demod, buf_f[i], i, record_channel);
}
return 0;
}
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