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author | FreeArtMan <=> | 2015-09-19 14:36:47 +0100 |
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committer | FreeArtMan <=> | 2015-09-19 14:36:47 +0100 |
commit | f8b84cf48099fb020b1174c8cc6195dde42308c3 (patch) | |
tree | 56a2ecbb7456c047d404c2b88c57e3d3be057ec7 /utils/rtl_sdr.c | |
download | r820t-f8b84cf48099fb020b1174c8cc6195dde42308c3.tar.gz r820t-f8b84cf48099fb020b1174c8cc6195dde42308c3.zip |
Initial
Diffstat (limited to 'utils/rtl_sdr.c')
-rw-r--r-- | utils/rtl_sdr.c | 278 |
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; +} |