Initial

1 files changed, 278 insertions, 0 deletions

diff --git a/src/rtl_sdr.c b/src/rtl_sdr.c
new file mode 100644
index 0000000..e6537ca
--- /dev/null
+++ b/src/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;
+}