B-Netz: Add dial sequence generator to emulate call setup from mobile phone

2 files changed, 441 insertions, 1 deletions

diff --git a/src/bnetz/Makefile.am b/src/bnetz/Makefile.am
index e00c026..bc562e9 100644
--- a/src/bnetz/Makefile.am
+++ b/src/bnetz/Makefile.am
@@ -1,7 +1,8 @@
 AM_CPPFLAGS = -Wall -Wextra -g $(all_includes)
 
 bin_PROGRAMS = \
-	bnetz
+	bnetz \
+	bnetz-dialer
 
 bnetz_SOURCES = \
 	bnetz.c \
@@ -30,10 +31,29 @@ bnetz_LDADD = \
 	$(top_builddir)/src/libsample/libsample.a \
 	-lm
 
+bnetz_dialer_SOURCES = \
+	telegramm.c \
+	dialer.c
+bnetz_dialer_LDADD = \
+	$(COMMON_LA) \
+	$(top_builddir)/src/libdebug/libdebug.a \
+	$(top_builddir)/src/libfsk/libfsk.a \
+	$(top_builddir)/src/libfm/libfm.a \
+	$(top_builddir)/src/libfilter/libfilter.a \
+	$(top_builddir)/src/libwave/libwave.a \
+	$(top_builddir)/src/libmncc/libmncc.a \
+	$(top_builddir)/src/libsample/libsample.a \
+	$(ALSA_LIBS)
+	-lm
+
 if HAVE_ALSA
 bnetz_LDADD += \
 	$(top_builddir)/src/libsound/libsound.a \
 	$(ALSA_LIBS)
+
+bnetz_dialer_LDADD += \
+	$(top_builddir)/src/libsound/libsound.a \
+	$(ALSA_LIBS)
 endif
 
 if HAVE_SDR
@@ -44,3 +64,7 @@ bnetz_LDADD += \
 	$(SOAPY_LIBS)
 endif
 
+if HAVE_ALSA
+AM_CPPFLAGS += -DHAVE_ALSA
+endif
+
diff --git a/src/bnetz/dialer.c b/src/bnetz/dialer.c
new file mode 100644
index 0000000..a3a292d
--- /dev/null
+++ b/src/bnetz/dialer.c
@@ -0,0 +1,416 @@
+/* B-Netz dialer
+ *
+ * (C) 2018 by Andreas Eversberg <jolly@eversberg.eu>
+ * All Rights Reserved
+ *
+ * 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 3 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 <stdio.h>
+#include <stdint.h>
+#include <getopt.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include "../libsample/sample.h"
+#include "../libfsk/fsk.h"
+#include "../libwave/wave.h"
+#include "../libdebug/debug.h"
+#ifdef HAVE_ALSA
+#include "../libsound/sound.h"
+#endif
+#include "telegramm.h"
+
+#define MAX_PAUSE	0.5	/* pause before and after dialing sequence */
+#define F0		2070.0
+#define F1		1950.0
+#define BIT_RATE	100.0
+
+/* presets */
+char start_digit = 's';
+const char *station_id = "50993";
+const char *dialing;
+const char *audiodev = "hw:0,0";
+int samplerate = 48000;
+const char *write_tx_wave = NULL;
+int latency = 50;
+
+/* states */
+enum tx_mode {
+	TX_MODE_SILENCE,
+	TX_MODE_FSK,
+	TX_MODE_DONE,
+} tx_mode = TX_MODE_SILENCE;
+int tx_silence_count = 0;
+char funkwahl[128];
+int digit_pos = 0;
+const char *tx_telegramm = NULL;
+int tx_telegramm_pos = 0;
+int latspl;
+
+/* instances */
+fsk_t fsk;
+#ifdef HAVE_ALSA
+void *audio = NULL;
+#endif
+wave_rec_t wave_tx_rec;
+
+/* dummy functions */
+int num_kanal = 1; /* only one channel used for debugging */
+void display_status_limit_scroll() {}
+void *get_sender_by_empfangsfrequenz() { return NULL; }
+void display_measurements_add() {}
+void display_measurements_update() {}
+
+#define OPT_METERING	1000
+#define OPT_COIN_BOX	1001
+
+static void print_help(const char *arg0)
+{
+	printf("Usage: %s [options] <number>\n\n", arg0);
+	/*      -                                                                             - */
+	printf("This program generates a dialing sequence to make a call via B-Netz base\n");
+	printf("station using an amateur radio transceiver.\n");
+	printf("Also it can write an audio file (wave) to be fed into B-Netz base station for\n");
+	printf("showing how it simulates a B-Netz phone doing an outgoing call.\n\n");
+	printf(" -h --help\n");
+	printf("        This help\n");
+	printf(" -i --station-id <station ID>\n");
+	printf("        5 Digits of ID of mobile station (default = '%s')\n", station_id);
+#ifdef HAVE_ALSA
+	printf(" -a --audio-device hw:<card>,<device>\n");
+	printf("        Sound card and device number (default = '%s')\n", audiodev);
+#endif
+	printf("        Don't set it for SDR!\n");
+	printf(" -s --samplerate <rate>\n");
+	printf("        Sample rate of sound device (default = '%d')\n", samplerate);
+	printf(" -w --write-tx-wave <file>\n");
+	printf("        Write audio to given wave file also.\n");
+	printf(" -g --gebuehenimpuls\n");
+	printf(" -g --metering\n");
+	printf("        Indicate to base station that we have a charge meter on board.\n");
+	printf("        This will allow the base station to send billing tones during call.\n");
+	printf(" -m --muenztelefon\n");
+	printf(" -m --coin-box\n");
+	printf("        Indicate to base station that we are a pay phone. ('Muenztelefon')\n");
+}
+
+static int handle_options(int argc, char **argv)
+{
+	const char *optstring;
+	int skip_args = 0;
+
+	static struct option long_options[] = {
+		{"help", 0, 0, 'h'},
+		{"station-id", 1, 0, 'i'},
+		{"audio-device", 1, 0, 'a'},
+		{"samplerate", 1, 0, 's'},
+		{"write-tx-wave", 1, 0, 'w'},
+		{"gebuehrenimpuls", 0, 0, 'g'},
+		{"metering", 0, 0, OPT_METERING},
+		{"muenztelefon", 0, 0, 'm'},
+		{"coin-box", 0, 0, OPT_COIN_BOX},
+		{0, 0, 0, 0},
+	};
+
+	optstring = "hi:a:s:w:gm";
+
+	while (1) {
+		int option_index = 0, c;
+
+		c = getopt_long(argc, argv, optstring, long_options, &option_index);
+
+		if (c == -1)
+			break;
+
+		switch (c) {
+		case 'h':
+			print_help(argv[0]);
+			exit(0);
+		case 'i':
+			station_id = strdup(optarg);
+			skip_args += 2;
+			break;
+		case 'a':
+			audiodev = strdup(optarg);
+			skip_args += 2;
+			break;
+		case 's':
+			samplerate = atoi(optarg);
+			skip_args += 2;
+			break;
+		case 'w':
+			write_tx_wave = strdup(optarg);
+			skip_args += 2;
+			break;
+		case 'g':
+		case OPT_METERING:
+			start_digit = 'S';
+			skip_args += 1;
+			break;
+		case 'm':
+		case OPT_COIN_BOX:
+			start_digit = 'M';
+			skip_args += 1;
+			break;
+		default:
+			break;
+		}
+	}
+
+	return skip_args;
+}
+
+
+/* process next fsk bit.
+ * if the dial string terminats, change to SILENCE mode
+ */
+static int fsk_send_bit(void __attribute__((unused)) *inst)
+{
+	struct impulstelegramm *impulstelegramm;
+
+	if (!tx_telegramm || tx_telegramm_pos == 16) {
+		switch (funkwahl[digit_pos]) {
+		case '\0':
+			PDEBUG(DBNETZ, DEBUG_INFO, "Done sending dialing sequence\n");
+			tx_mode = TX_MODE_SILENCE;
+			tx_silence_count = 0;
+			return -1;
+		case 'w':
+			if (!tx_telegramm)
+				PDEBUG(DBNETZ, DEBUG_INFO, "Sending channel allocation tone ('Kanalbelegung')\n");
+			tx_telegramm = "0000000000000000";
+			tx_telegramm_pos = 0;
+			digit_pos++;
+			break;
+		default:
+			switch (funkwahl[digit_pos]) {
+			case 's':
+				PDEBUG(DBNETZ, DEBUG_INFO, "Sending start digit (no charging meater on board)\n");
+				break;
+			case 'S':
+				PDEBUG(DBNETZ, DEBUG_INFO, "Sending start digit (with charging meater on board)\n");
+				break;
+			case 'M':
+				PDEBUG(DBNETZ, DEBUG_INFO, "Sending start digit (Phone is a coin box.)\n");
+				break;
+			case 'e':
+				PDEBUG(DBNETZ, DEBUG_INFO, "Sending stop digit\n");
+				break;
+			default:
+				PDEBUG(DBNETZ, DEBUG_INFO, "Sending digit '%c'\n", funkwahl[digit_pos]);
+			}
+			impulstelegramm = bnetz_digit2telegramm(funkwahl[digit_pos]);
+			if (!impulstelegramm) {
+				PDEBUG(DBNETZ, DEBUG_ERROR, "Illegal digit '%c', please fix!\n", funkwahl[digit_pos]);
+				abort();
+			}
+			tx_telegramm = impulstelegramm->sequence;
+			tx_telegramm_pos = 0;
+			digit_pos++;
+		}
+	}
+
+	return tx_telegramm[tx_telegramm_pos++];
+}
+
+/* encode audio */
+static void encode_audio(sample_t *samples, uint8_t *power, int length)
+{
+	int count;
+
+	memset(power, 1, length);
+
+again:
+	switch (tx_mode) {
+	case TX_MODE_SILENCE:
+		memset(samples, 0, length * sizeof(*samples));
+		tx_silence_count += length;
+		if (tx_silence_count >= (int)((double)samplerate * MAX_PAUSE)) {
+			if (funkwahl[digit_pos])
+				tx_mode = TX_MODE_FSK;
+			else
+				tx_mode = TX_MODE_DONE;
+		}
+		break;
+	case TX_MODE_FSK:
+		/* send FSK until it stops, then fill with silence */
+		count = fsk_send(&fsk, samples, length, 0);
+		samples += count;
+		length -= count;
+		if (length)
+			goto again;
+		break;
+	default:
+		break;
+	}
+}
+
+/* loop that gets audio from encoder and fowards it to sound card.
+ * alternatively a sound file is written.
+ */
+static void process_signal(void)
+{
+	sample_t buff[latspl], *samples[1] = { buff };
+        uint8_t pbuff[latspl], *power[1] = { pbuff };
+	int count;
+	int __attribute__((unused)) rc;
+
+	while (tx_mode != TX_MODE_DONE) {
+#ifdef HAVE_ALSA
+		count = sound_get_tosend(audio, latspl);
+#else
+		count = samplerate / 1000;
+#endif
+		if (count < 0) {
+			PDEBUG(DDSP, DEBUG_ERROR, "Failed to get number of samples in buffer (rc = %d)!\n", count);
+			break;
+		}
+
+		/* get fsk / silence */
+		encode_audio(samples[0], power[0], count);
+
+		/* write wave, if open */
+		if (wave_tx_rec.fp)
+			wave_write(&wave_tx_rec, samples, count);
+
+#ifdef HAVE_ALSA
+		/* write audio */
+		rc = sound_write(audio, samples, power, count, NULL, NULL, 1);
+		if (rc < 0) {
+			PDEBUG(DDSP, DEBUG_ERROR, "Failed to write TX data to audio device (rc = %d)\n", rc);
+			break;
+		}
+#endif
+
+		/* sleep a while */
+		usleep(1000);
+	}
+}
+
+int main(int argc, char *argv[])
+{
+	const char *arg0 = argv[0];
+	int skip_args;
+	int i;
+	int rc;
+
+	/* init */
+	bnetz_init_telegramm();
+	memset(&fsk, 0, sizeof(fsk));
+
+	/* latency of send buffer in samples */
+	latspl = samplerate * latency / 1000;
+
+	skip_args = handle_options(argc, argv);
+	argc -= skip_args;
+	argv += skip_args;
+
+	if (argc <= 1) {
+		printf("No phone number given!\n\n");
+		print_help(arg0);
+		goto exit;
+	}
+
+	/* check for valid station ID */
+	if (strlen(station_id) != 5) {
+		printf("Given station ID '%s' has too many digits!\n", station_id);
+		goto exit;
+	}
+	for (i = 0; station_id[i]; i++) {
+		if (station_id[i] < '0' || station_id[i] > '9') {
+			printf("Given station ID '%s' has invalid digits!\n", station_id);
+			goto exit;
+		}
+	}
+
+	/* check for valid phone number */
+	dialing = argv[1];
+	if (strlen(dialing) < 4) {
+		printf("Given phone number '%s' has too few digits! (less than minimum of 4 digits)\n", dialing);
+		goto exit;
+	}
+	if (strlen(dialing) > 14) {
+		printf("Given phone number '%s' has too many digits! (more than allowed 14 digits)\n", dialing);
+		goto exit;
+	}
+	for (i = 0; dialing[i]; i++) {
+		if (dialing[i] < '0' || dialing[i] > '9') {
+			printf("Given phone number '%s' has invalid digits!\n", dialing);
+			goto exit;
+		}
+	}
+	if (dialing[0] != '0') {
+		printf("Given phone number '%s' does not start with 0!\n", dialing);
+		goto exit;
+	}
+
+	/* dial string: 640 ms pause, 640 ms 2070 HZ, 2 * {start, station ID, number, stop}, 640 ms pause */
+	sprintf(funkwahl, "wwww%c%s%se%c%s%se", start_digit, station_id, dialing + 1, start_digit, station_id, dialing + 1);
+
+	/* init fsk */
+	if (fsk_init(&fsk, NULL, fsk_send_bit, NULL, samplerate, BIT_RATE, F0, F1, 1.0, 0, 0) < 0) {
+		PDEBUG(DDSP, DEBUG_ERROR, "FSK init failed!\n");
+		goto exit;
+	}
+
+#ifdef HAVE_ALSA
+	/* init sound */
+	audio = sound_open(audiodev, NULL, NULL, 1, 0.0, samplerate, latspl, 1.0, 4000.0);
+	if (!audio) {
+		PDEBUG(DBNETZ, DEBUG_ERROR, "No sound device!\n");
+		goto exit;
+	}
+#endif
+
+	/* open wave */
+	if (write_tx_wave) {
+		rc = wave_create_record(&wave_tx_rec, write_tx_wave, samplerate, 1, 1.0);
+		if (rc < 0) {
+			PDEBUG(DBNETZ, DEBUG_ERROR, "Failed to create WAVE recoding instance!\n");
+			goto exit;
+		}
+	}
+#ifndef HAVE_ALSA
+	else {
+		PDEBUG(DBNETZ, DEBUG_ERROR, "No sound support compiled in, so you need to write to a wave file. See help!\n");
+		goto exit;
+	}
+#endif
+
+#ifdef HAVE_ALSA
+	/* start sound */
+	sound_start(audio);
+#endif
+
+	PDEBUG(DBNETZ, DEBUG_ERROR, "Start audio after pause...\n");
+
+	process_signal();
+
+exit:
+	/* close wave */
+	wave_destroy_record(&wave_tx_rec);
+
+#ifdef HAVE_ALSA
+	/* exit sound */
+	if (audio)
+		sound_close(audio);
+#endif
+
+	/* exit fsk */
+	fsk_cleanup(&fsk);
+
+	return 0;
+}
+