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-rw-r--r--utils/rtl_sdr.c278
1 files changed, 278 insertions, 0 deletions
diff --git a/utils/rtl_sdr.c b/utils/rtl_sdr.c
new file mode 100644
index 0000000..e6537ca
--- /dev/null
+++ b/utils/rtl_sdr.c
@@ -0,0 +1,278 @@
+/*
+ * rtl-sdr, turns your Realtek RTL2832 based DVB dongle into a SDR receiver
+ * Copyright (C) 2012 by Steve Markgraf <steve@steve-m.de>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+#include <errno.h>
+#include <signal.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#ifndef _WIN32
+#include <unistd.h>
+#else
+#include <windows.h>
+#include <io.h>
+#include <fcntl.h>
+#include "getopt/getopt.h"
+#endif
+
+#include "rtl-sdr.h"
+#include "convenience/convenience.h"
+
+#define DEFAULT_SAMPLE_RATE 2048000
+#define DEFAULT_BUF_LENGTH (16 * 16384)
+#define MINIMAL_BUF_LENGTH 512
+#define MAXIMAL_BUF_LENGTH (256 * 16384)
+
+static int do_exit = 0;
+static uint32_t bytes_to_read = 0;
+static rtlsdr_dev_t *dev = NULL;
+
+void usage(void)
+{
+ fprintf(stderr,
+ "rtl_sdr, an I/Q recorder for RTL2832 based DVB-T receivers\n\n"
+ "Usage:\t -f frequency_to_tune_to [Hz]\n"
+ "\t[-s samplerate (default: 2048000 Hz)]\n"
+ "\t[-d device_index (default: 0)]\n"
+ "\t[-g gain (default: 0 for auto)]\n"
+ "\t[-p ppm_error (default: 0)]\n"
+ "\t[-b output_block_size (default: 16 * 16384)]\n"
+ "\t[-n number of samples to read (default: 0, infinite)]\n"
+ "\t[-S force sync output (default: async)]\n"
+ "\tfilename (a '-' dumps samples to stdout)\n\n");
+ exit(1);
+}
+
+#ifdef _WIN32
+BOOL WINAPI
+sighandler(int signum)
+{
+ if (CTRL_C_EVENT == signum) {
+ fprintf(stderr, "Signal caught, exiting!\n");
+ do_exit = 1;
+ rtlsdr_cancel_async(dev);
+ return TRUE;
+ }
+ return FALSE;
+}
+#else
+static void sighandler(int signum)
+{
+ fprintf(stderr, "Signal caught, exiting!\n");
+ do_exit = 1;
+ rtlsdr_cancel_async(dev);
+}
+#endif
+
+static void rtlsdr_callback(unsigned char *buf, uint32_t len, void *ctx)
+{
+ if (ctx) {
+ if (do_exit)
+ return;
+
+ if ((bytes_to_read > 0) && (bytes_to_read < len)) {
+ len = bytes_to_read;
+ do_exit = 1;
+ rtlsdr_cancel_async(dev);
+ }
+
+ if (fwrite(buf, 1, len, (FILE*)ctx) != len) {
+ fprintf(stderr, "Short write, samples lost, exiting!\n");
+ rtlsdr_cancel_async(dev);
+ }
+
+ if (bytes_to_read > 0)
+ bytes_to_read -= len;
+ }
+}
+
+int main(int argc, char **argv)
+{
+#ifndef _WIN32
+ struct sigaction sigact;
+#endif
+ char *filename = NULL;
+ int n_read;
+ int r, opt;
+ int gain = 0;
+ int ppm_error = 0;
+ int sync_mode = 0;
+ FILE *file;
+ uint8_t *buffer;
+ int dev_index = 0;
+ int dev_given = 0;
+ uint32_t frequency = 100000000;
+ uint32_t samp_rate = DEFAULT_SAMPLE_RATE;
+ uint32_t out_block_size = DEFAULT_BUF_LENGTH;
+
+ while ((opt = getopt(argc, argv, "d:f:g:s:b:n:p:S")) != -1) {
+ switch (opt) {
+ case 'd':
+ dev_index = verbose_device_search(optarg);
+ dev_given = 1;
+ break;
+ case 'f':
+ frequency = (uint32_t)atofs(optarg);
+ break;
+ case 'g':
+ gain = (int)(atof(optarg) * 10); /* tenths of a dB */
+ break;
+ case 's':
+ samp_rate = (uint32_t)atofs(optarg);
+ break;
+ case 'p':
+ ppm_error = atoi(optarg);
+ break;
+ case 'b':
+ out_block_size = (uint32_t)atof(optarg);
+ break;
+ case 'n':
+ bytes_to_read = (uint32_t)atof(optarg) * 2;
+ break;
+ case 'S':
+ sync_mode = 1;
+ break;
+ default:
+ usage();
+ break;
+ }
+ }
+
+ if (argc <= optind) {
+ usage();
+ } else {
+ filename = argv[optind];
+ }
+
+ if(out_block_size < MINIMAL_BUF_LENGTH ||
+ out_block_size > MAXIMAL_BUF_LENGTH ){
+ fprintf(stderr,
+ "Output block size wrong value, falling back to default\n");
+ fprintf(stderr,
+ "Minimal length: %u\n", MINIMAL_BUF_LENGTH);
+ fprintf(stderr,
+ "Maximal length: %u\n", MAXIMAL_BUF_LENGTH);
+ out_block_size = DEFAULT_BUF_LENGTH;
+ }
+
+ buffer = malloc(out_block_size * sizeof(uint8_t));
+
+ if (!dev_given) {
+ dev_index = verbose_device_search("0");
+ }
+
+ if (dev_index < 0) {
+ exit(1);
+ }
+
+ r = rtlsdr_open(&dev, (uint32_t)dev_index);
+ if (r < 0) {
+ fprintf(stderr, "Failed to open rtlsdr device #%d.\n", dev_index);
+ exit(1);
+ }
+#ifndef _WIN32
+ sigact.sa_handler = sighandler;
+ sigemptyset(&sigact.sa_mask);
+ sigact.sa_flags = 0;
+ sigaction(SIGINT, &sigact, NULL);
+ sigaction(SIGTERM, &sigact, NULL);
+ sigaction(SIGQUIT, &sigact, NULL);
+ sigaction(SIGPIPE, &sigact, NULL);
+#else
+ SetConsoleCtrlHandler( (PHANDLER_ROUTINE) sighandler, TRUE );
+#endif
+ /* Set the sample rate */
+ verbose_set_sample_rate(dev, samp_rate);
+
+ /* Set the frequency */
+ verbose_set_frequency(dev, frequency);
+
+ if (0 == gain) {
+ /* Enable automatic gain */
+ verbose_auto_gain(dev);
+ } else {
+ /* Enable manual gain */
+ gain = nearest_gain(dev, gain);
+ verbose_gain_set(dev, gain);
+ }
+
+ verbose_ppm_set(dev, ppm_error);
+
+ if(strcmp(filename, "-") == 0) { /* Write samples to stdout */
+ file = stdout;
+#ifdef _WIN32
+ _setmode(_fileno(stdin), _O_BINARY);
+#endif
+ } else {
+ file = fopen(filename, "wb");
+ if (!file) {
+ fprintf(stderr, "Failed to open %s\n", filename);
+ goto out;
+ }
+ }
+
+ /* Reset endpoint before we start reading from it (mandatory) */
+ verbose_reset_buffer(dev);
+
+ if (sync_mode) {
+ fprintf(stderr, "Reading samples in sync mode...\n");
+ while (!do_exit) {
+ r = rtlsdr_read_sync(dev, buffer, out_block_size, &n_read);
+ if (r < 0) {
+ fprintf(stderr, "WARNING: sync read failed.\n");
+ break;
+ }
+
+ if ((bytes_to_read > 0) && (bytes_to_read < (uint32_t)n_read)) {
+ n_read = bytes_to_read;
+ do_exit = 1;
+ }
+
+ if (fwrite(buffer, 1, n_read, file) != (size_t)n_read) {
+ fprintf(stderr, "Short write, samples lost, exiting!\n");
+ break;
+ }
+
+ if ((uint32_t)n_read < out_block_size) {
+ fprintf(stderr, "Short read, samples lost, exiting!\n");
+ break;
+ }
+
+ if (bytes_to_read > 0)
+ bytes_to_read -= n_read;
+ }
+ } else {
+ fprintf(stderr, "Reading samples in async mode...\n");
+ r = rtlsdr_read_async(dev, rtlsdr_callback, (void *)file,
+ 0, out_block_size);
+ }
+
+ if (do_exit)
+ fprintf(stderr, "\nUser cancel, exiting...\n");
+ else
+ fprintf(stderr, "\nLibrary error %d, exiting...\n", r);
+
+ if (file != stdout)
+ fclose(file);
+
+ rtlsdr_close(dev);
+ free (buffer);
+out:
+ return r >= 0 ? r : -r;
+}