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-rw-r--r--binding.pri6
-rw-r--r--binding.pro11
-rw-r--r--convenience/convenience.c304
-rw-r--r--convenience/convenience.h142
-rw-r--r--export.map1
-rw-r--r--radio-binding.c493
-rw-r--r--radio_impl.h76
-rw-r--r--radio_impl_rtlsdr.c254
-rw-r--r--radio_output.c294
-rw-r--r--radio_output.h31
-rw-r--r--rtl_fm.c1267
-rw-r--r--rtl_fm.h70
12 files changed, 2949 insertions, 0 deletions
diff --git a/binding.pri b/binding.pri
new file mode 100644
index 0000000..3448a56
--- /dev/null
+++ b/binding.pri
@@ -0,0 +1,6 @@
+TEMPLATE = lib
+CONFIG += plugin use_c_linker
+CONFIG -= qt
+QMAKE_CFLAGS += -Wextra -Wconversion -Wno-unused-parameter -Werror=maybe-uninitialized -Werror=implicit-function-declaration -ffunction-sections -fdata-sections -Wl,--as-needed -Wl,--gc-sections
+
+DESTDIR = $${OUT_PWD}/../package/root/lib
diff --git a/binding.pro b/binding.pro
new file mode 100644
index 0000000..d8c5a93
--- /dev/null
+++ b/binding.pro
@@ -0,0 +1,11 @@
+TARGET = radio-binding
+
+HEADERS = radio_impl.h radio_output.h rtl_fm.h convenience/convenience.h
+SOURCES = radio-binding.c radio_output.c radio_impl_rtlsdr.c rtl_fm.c convenience/convenience.c
+
+LIBS += -Wl,--version-script=$$PWD/export.map
+
+CONFIG += link_pkgconfig
+PKGCONFIG += json-c afb-daemon librtlsdr glib-2.0 libpulse-simple
+
+include(binding.pri)
diff --git a/convenience/convenience.c b/convenience/convenience.c
new file mode 100644
index 0000000..517dc4e
--- /dev/null
+++ b/convenience/convenience.c
@@ -0,0 +1,304 @@
+/*
+ * Copyright (C) 2014 by Kyle Keen <keenerd@gmail.com>
+ *
+ * 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/>.
+ */
+
+/* a collection of user friendly tools
+ * todo: use strtol for more flexible int parsing
+ * */
+
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+
+#ifndef _WIN32
+#include <unistd.h>
+#else
+#include <windows.h>
+#include <fcntl.h>
+#include <io.h>
+#define _USE_MATH_DEFINES
+#endif
+
+#include <math.h>
+
+#include "rtl-sdr.h"
+
+double atofs(char *s)
+/* standard suffixes */
+{
+ char last;
+ int len;
+ double suff = 1.0;
+ len = strlen(s);
+ last = s[len-1];
+ s[len-1] = '\0';
+ switch (last) {
+ case 'g':
+ case 'G':
+ suff *= 1e3;
+ case 'm':
+ case 'M':
+ suff *= 1e3;
+ case 'k':
+ case 'K':
+ suff *= 1e3;
+ suff *= atof(s);
+ s[len-1] = last;
+ return suff;
+ }
+ s[len-1] = last;
+ return atof(s);
+}
+
+double atoft(char *s)
+/* time suffixes, returns seconds */
+{
+ char last;
+ int len;
+ double suff = 1.0;
+ len = strlen(s);
+ last = s[len-1];
+ s[len-1] = '\0';
+ switch (last) {
+ case 'h':
+ case 'H':
+ suff *= 60;
+ case 'm':
+ case 'M':
+ suff *= 60;
+ case 's':
+ case 'S':
+ suff *= atof(s);
+ s[len-1] = last;
+ return suff;
+ }
+ s[len-1] = last;
+ return atof(s);
+}
+
+double atofp(char *s)
+/* percent suffixes */
+{
+ char last;
+ int len;
+ double suff = 1.0;
+ len = strlen(s);
+ last = s[len-1];
+ s[len-1] = '\0';
+ switch (last) {
+ case '%':
+ suff *= 0.01;
+ suff *= atof(s);
+ s[len-1] = last;
+ return suff;
+ }
+ s[len-1] = last;
+ return atof(s);
+}
+
+int nearest_gain(rtlsdr_dev_t *dev, int target_gain)
+{
+ int i, r, err1, err2, count, nearest;
+ int* gains;
+ r = rtlsdr_set_tuner_gain_mode(dev, 1);
+ if (r < 0) {
+ fprintf(stderr, "WARNING: Failed to enable manual gain.\n");
+ return r;
+ }
+ count = rtlsdr_get_tuner_gains(dev, NULL);
+ if (count <= 0) {
+ return 0;
+ }
+ gains = malloc(sizeof(int) * count);
+ count = rtlsdr_get_tuner_gains(dev, gains);
+ nearest = gains[0];
+ for (i=0; i<count; i++) {
+ err1 = abs(target_gain - nearest);
+ err2 = abs(target_gain - gains[i]);
+ if (err2 < err1) {
+ nearest = gains[i];
+ }
+ }
+ free(gains);
+ return nearest;
+}
+
+int verbose_set_frequency(rtlsdr_dev_t *dev, uint32_t frequency)
+{
+ int r;
+ r = rtlsdr_set_center_freq(dev, frequency);
+ if (r < 0) {
+ fprintf(stderr, "WARNING: Failed to set center freq.\n");
+ } else {
+ fprintf(stderr, "Tuned to %u Hz.\n", frequency);
+ }
+ return r;
+}
+
+int verbose_set_sample_rate(rtlsdr_dev_t *dev, uint32_t samp_rate)
+{
+ int r;
+ r = rtlsdr_set_sample_rate(dev, samp_rate);
+ if (r < 0) {
+ fprintf(stderr, "WARNING: Failed to set sample rate.\n");
+ } else {
+ fprintf(stderr, "Sampling at %u S/s.\n", samp_rate);
+ }
+ return r;
+}
+
+int verbose_direct_sampling(rtlsdr_dev_t *dev, int on)
+{
+ int r;
+ r = rtlsdr_set_direct_sampling(dev, on);
+ if (r != 0) {
+ fprintf(stderr, "WARNING: Failed to set direct sampling mode.\n");
+ return r;
+ }
+ if (on == 0) {
+ fprintf(stderr, "Direct sampling mode disabled.\n");}
+ if (on == 1) {
+ fprintf(stderr, "Enabled direct sampling mode, input 1/I.\n");}
+ if (on == 2) {
+ fprintf(stderr, "Enabled direct sampling mode, input 2/Q.\n");}
+ return r;
+}
+
+int verbose_offset_tuning(rtlsdr_dev_t *dev)
+{
+ int r;
+ r = rtlsdr_set_offset_tuning(dev, 1);
+ if (r != 0) {
+ fprintf(stderr, "WARNING: Failed to set offset tuning.\n");
+ } else {
+ fprintf(stderr, "Offset tuning mode enabled.\n");
+ }
+ return r;
+}
+
+int verbose_auto_gain(rtlsdr_dev_t *dev)
+{
+ int r;
+ r = rtlsdr_set_tuner_gain_mode(dev, 0);
+ if (r != 0) {
+ fprintf(stderr, "WARNING: Failed to set tuner gain.\n");
+ } else {
+ fprintf(stderr, "Tuner gain set to automatic.\n");
+ }
+ return r;
+}
+
+int verbose_gain_set(rtlsdr_dev_t *dev, int gain)
+{
+ int r;
+ r = rtlsdr_set_tuner_gain_mode(dev, 1);
+ if (r < 0) {
+ fprintf(stderr, "WARNING: Failed to enable manual gain.\n");
+ return r;
+ }
+ r = rtlsdr_set_tuner_gain(dev, gain);
+ if (r != 0) {
+ fprintf(stderr, "WARNING: Failed to set tuner gain.\n");
+ } else {
+ fprintf(stderr, "Tuner gain set to %0.2f dB.\n", gain/10.0);
+ }
+ return r;
+}
+
+int verbose_ppm_set(rtlsdr_dev_t *dev, int ppm_error)
+{
+ int r;
+ if (ppm_error == 0) {
+ return 0;}
+ r = rtlsdr_set_freq_correction(dev, ppm_error);
+ if (r < 0) {
+ fprintf(stderr, "WARNING: Failed to set ppm error.\n");
+ } else {
+ fprintf(stderr, "Tuner error set to %i ppm.\n", ppm_error);
+ }
+ return r;
+}
+
+int verbose_reset_buffer(rtlsdr_dev_t *dev)
+{
+ int r;
+ r = rtlsdr_reset_buffer(dev);
+ if (r < 0) {
+ fprintf(stderr, "WARNING: Failed to reset buffers.\n");}
+ return r;
+}
+
+int verbose_device_search(char *s)
+{
+ int i, device_count, device, offset;
+ char *s2;
+ char vendor[256], product[256], serial[256];
+ device_count = rtlsdr_get_device_count();
+ if (!device_count) {
+ fprintf(stderr, "No supported devices found.\n");
+ return -1;
+ }
+ fprintf(stderr, "Found %d device(s):\n", device_count);
+ for (i = 0; i < device_count; i++) {
+ rtlsdr_get_device_usb_strings(i, vendor, product, serial);
+ fprintf(stderr, " %d: %s, %s, SN: %s\n", i, vendor, product, serial);
+ }
+ fprintf(stderr, "\n");
+ /* does string look like raw id number */
+ device = (int)strtol(s, &s2, 0);
+ if (s2[0] == '\0' && device >= 0 && device < device_count) {
+ fprintf(stderr, "Using device %d: %s\n",
+ device, rtlsdr_get_device_name((uint32_t)device));
+ return device;
+ }
+ /* does string exact match a serial */
+ for (i = 0; i < device_count; i++) {
+ rtlsdr_get_device_usb_strings(i, vendor, product, serial);
+ if (strcmp(s, serial) != 0) {
+ continue;}
+ device = i;
+ fprintf(stderr, "Using device %d: %s\n",
+ device, rtlsdr_get_device_name((uint32_t)device));
+ return device;
+ }
+ /* does string prefix match a serial */
+ for (i = 0; i < device_count; i++) {
+ rtlsdr_get_device_usb_strings(i, vendor, product, serial);
+ if (strncmp(s, serial, strlen(s)) != 0) {
+ continue;}
+ device = i;
+ fprintf(stderr, "Using device %d: %s\n",
+ device, rtlsdr_get_device_name((uint32_t)device));
+ return device;
+ }
+ /* does string suffix match a serial */
+ for (i = 0; i < device_count; i++) {
+ rtlsdr_get_device_usb_strings(i, vendor, product, serial);
+ offset = strlen(serial) - strlen(s);
+ if (offset < 0) {
+ continue;}
+ if (strncmp(s, serial+offset, strlen(s)) != 0) {
+ continue;}
+ device = i;
+ fprintf(stderr, "Using device %d: %s\n",
+ device, rtlsdr_get_device_name((uint32_t)device));
+ return device;
+ }
+ fprintf(stderr, "No matching devices found.\n");
+ return -1;
+}
+
+// vim: tabstop=8:softtabstop=8:shiftwidth=8:noexpandtab
diff --git a/convenience/convenience.h b/convenience/convenience.h
new file mode 100644
index 0000000..1faa2af
--- /dev/null
+++ b/convenience/convenience.h
@@ -0,0 +1,142 @@
+/*
+ * Copyright (C) 2014 by Kyle Keen <keenerd@gmail.com>
+ *
+ * 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/>.
+ */
+
+/* a collection of user friendly tools */
+
+/*!
+ * Convert standard suffixes (k, M, G) to double
+ *
+ * \param s a string to be parsed
+ * \return double
+ */
+
+double atofs(char *s);
+
+/*!
+ * Convert time suffixes (s, m, h) to double
+ *
+ * \param s a string to be parsed
+ * \return seconds as double
+ */
+
+double atoft(char *s);
+
+/*!
+ * Convert percent suffixe (%) to double
+ *
+ * \param s a string to be parsed
+ * \return double
+ */
+
+double atofp(char *s);
+
+/*!
+ * Find nearest supported gain
+ *
+ * \param dev the device handle given by rtlsdr_open()
+ * \param target_gain in tenths of a dB
+ * \return 0 on success
+ */
+
+int nearest_gain(rtlsdr_dev_t *dev, int target_gain);
+
+/*!
+ * Set device frequency and report status on stderr
+ *
+ * \param dev the device handle given by rtlsdr_open()
+ * \param frequency in Hz
+ * \return 0 on success
+ */
+
+int verbose_set_frequency(rtlsdr_dev_t *dev, uint32_t frequency);
+
+/*!
+ * Set device sample rate and report status on stderr
+ *
+ * \param dev the device handle given by rtlsdr_open()
+ * \param samp_rate in samples/second
+ * \return 0 on success
+ */
+
+int verbose_set_sample_rate(rtlsdr_dev_t *dev, uint32_t samp_rate);
+
+/*!
+ * Enable or disable the direct sampling mode and report status on stderr
+ *
+ * \param dev the device handle given by rtlsdr_open()
+ * \param on 0 means disabled, 1 I-ADC input enabled, 2 Q-ADC input enabled
+ * \return 0 on success
+ */
+
+int verbose_direct_sampling(rtlsdr_dev_t *dev, int on);
+
+/*!
+ * Enable offset tuning and report status on stderr
+ *
+ * \param dev the device handle given by rtlsdr_open()
+ * \return 0 on success
+ */
+
+int verbose_offset_tuning(rtlsdr_dev_t *dev);
+
+/*!
+ * Enable auto gain and report status on stderr
+ *
+ * \param dev the device handle given by rtlsdr_open()
+ * \return 0 on success
+ */
+
+int verbose_auto_gain(rtlsdr_dev_t *dev);
+
+/*!
+ * Set tuner gain and report status on stderr
+ *
+ * \param dev the device handle given by rtlsdr_open()
+ * \param gain in tenths of a dB
+ * \return 0 on success
+ */
+
+int verbose_gain_set(rtlsdr_dev_t *dev, int gain);
+
+/*!
+ * Set the frequency correction value for the device and report status on stderr.
+ *
+ * \param dev the device handle given by rtlsdr_open()
+ * \param ppm_error correction value in parts per million (ppm)
+ * \return 0 on success
+ */
+
+int verbose_ppm_set(rtlsdr_dev_t *dev, int ppm_error);
+
+/*!
+ * Reset buffer
+ *
+ * \param dev the device handle given by rtlsdr_open()
+ * \return 0 on success
+ */
+
+int verbose_reset_buffer(rtlsdr_dev_t *dev);
+
+/*!
+ * Find the closest matching device.
+ *
+ * \param s a string to be parsed
+ * \return dev_index int, -1 on error
+ */
+
+int verbose_device_search(char *s);
+
diff --git a/export.map b/export.map
new file mode 100644
index 0000000..52c1b4a
--- /dev/null
+++ b/export.map
@@ -0,0 +1 @@
+{ global: afbBindingV1*; local: *; };
diff --git a/radio-binding.c b/radio-binding.c
new file mode 100644
index 0000000..12ed966
--- /dev/null
+++ b/radio-binding.c
@@ -0,0 +1,493 @@
+/*
+ * Copyright (C) 2017 Konsulko Group
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#define _GNU_SOURCE
+
+#include <stdlib.h>
+#include <string.h>
+#include <stdint.h>
+#include <unistd.h>
+#include <sys/types.h>
+
+#include <json-c/json.h>
+#include <afb/afb-binding.h>
+#include <afb/afb-service-itf.h>
+
+#include "radio_impl.h"
+
+static const struct afb_binding_interface *interface;
+
+static struct afb_event freq_event;
+static struct afb_event scan_event;
+
+static void freq_callback(uint32_t frequency, void *data)
+{
+ json_object *jresp = json_object_new_object();
+ json_object *value = json_object_new_int((int) frequency);
+
+ json_object_object_add(jresp, "value", value);
+ afb_event_push(freq_event, json_object_get(jresp));
+}
+
+static void scan_callback(uint32_t frequency, void *data)
+{
+ json_object *jresp = json_object_new_object();
+ json_object *value = json_object_new_int((int) frequency);
+
+ json_object_object_add(jresp, "value", value);
+ afb_event_push(scan_event, json_object_get(jresp));
+}
+
+/*
+ * Binding verb handlers
+ */
+
+/*
+ * @brief Get (and optionally set) frequency
+ *
+ * @param struct afb_req : an afb request structure
+ *
+ */
+static void frequency(struct afb_req request)
+{
+ json_object *ret_json;
+ const char *value = afb_req_value(request, "value");
+ uint32_t frequency;
+
+ if(value) {
+ char *p;
+ frequency = strtoul(value, &p, 10);
+ if(frequency && *p == '\0') {
+ radio_impl_set_frequency(frequency);
+ } else {
+ afb_req_fail(request, "failed", "Invalid scan direction");
+ return;
+ }
+ }
+ ret_json = json_object_new_object();
+ frequency = radio_impl_get_frequency();
+ json_object_object_add(ret_json, "frequency", json_object_new_int((int32_t) frequency));
+ afb_req_success(request, ret_json, NULL);
+}
+
+/*
+ * @brief Get (and optionally set) frequency band
+ *
+ * @param struct afb_req : an afb request structure
+ *
+ */
+static void band(struct afb_req request)
+{
+ json_object *ret_json;
+ const char *value = afb_req_value(request, "value");
+ int valid = 0;
+ radio_band_t band;
+ char band_name[4];
+
+ if(value) {
+ if(!strcasecmp(value, "AM")) {
+ band = BAND_AM;
+ valid = 1;
+ } else if(!strcasecmp(value, "FM")) {
+ band = BAND_FM;
+ valid = 1;
+ } else {
+ char *p;
+ band = strtoul(value, &p, 10);
+ if(p != value && *p == '\0') {
+ switch(band) {
+ case BAND_AM:
+ case BAND_FM:
+ valid = 1;
+ break;
+ default:
+ break;
+ }
+ }
+ }
+ if(valid) {
+ radio_impl_set_band(band);
+ } else {
+ afb_req_fail(request, "failed", "Invalid band");
+ return;
+ }
+ }
+ ret_json = json_object_new_object();
+ band = radio_impl_get_band();
+ sprintf(band_name, "%s", band == BAND_AM ? "AM" : "FM");
+ json_object_object_add(ret_json, "band", json_object_new_string(band_name));
+ afb_req_success(request, ret_json, NULL);
+}
+
+/*
+ * @brief Check if band is supported
+ *
+ * @param struct afb_req : an afb request structure
+ *
+ */
+static void band_supported(struct afb_req request)
+{
+ json_object *ret_json;
+ const char *value = afb_req_value(request, "band");
+ int valid = 0;
+ radio_band_t band;
+
+ if(value) {
+ if(!strcasecmp(value, "AM")) {
+ band = BAND_AM;
+ valid = 1;
+ } else if(!strcasecmp(value, "FM")) {
+ band = BAND_FM;
+ valid = 1;
+ } else {
+ char *p;
+ band = strtoul(value, &p, 10);
+ if(p != value && *p == '\0') {
+ switch(band) {
+ case BAND_AM:
+ case BAND_FM:
+ valid = 1;
+ break;
+ default:
+ break;
+ }
+ }
+ }
+ }
+ if(!valid) {
+ afb_req_fail(request, "failed", "Invalid band");
+ return;
+ }
+ ret_json = json_object_new_object();
+ json_object_object_add(ret_json,
+ "supported",
+ json_object_new_int(radio_impl_band_supported(band)));
+ afb_req_success(request, ret_json, NULL);
+}
+
+/*
+ * @brief Get frequency range for a band
+ *
+ * @param struct afb_req : an afb request structure
+ *
+ */
+static void frequency_range(struct afb_req request)
+{
+ json_object *ret_json;
+ const char *value = afb_req_value(request, "band");
+ int valid = 0;
+ radio_band_t band;
+ uint32_t min_frequency;
+ uint32_t max_frequency;
+
+ if(value) {
+ if(!strcasecmp(value, "AM")) {
+ band = BAND_AM;
+ valid = 1;
+ } else if(!strcasecmp(value, "FM")) {
+ band = BAND_FM;
+ valid = 1;
+ } else {
+ char *p;
+ band = strtoul(value, &p, 10);
+ if(p != value && *p == '\0') {
+ switch(band) {
+ case BAND_AM:
+ case BAND_FM:
+ valid = 1;
+ break;
+ default:
+ break;
+ }
+ }
+ }
+ }
+ if(!valid) {
+ afb_req_fail(request, "failed", "Invalid band");
+ return;
+ }
+ ret_json = json_object_new_object();
+ min_frequency = radio_impl_get_min_frequency(band);
+ max_frequency = radio_impl_get_max_frequency(band);
+ json_object_object_add(ret_json, "min", json_object_new_int((int32_t) min_frequency));
+ json_object_object_add(ret_json, "max", json_object_new_int((int32_t) max_frequency));
+ afb_req_success(request, ret_json, NULL);
+}
+
+/*
+ * @brief Get frequency step size (Hz) for a band
+ *
+ * @param struct afb_req : an afb request structure
+ *
+ */
+static void frequency_step(struct afb_req request)
+{
+ json_object *ret_json;
+ const char *value = afb_req_value(request, "band");
+ int valid = 0;
+ radio_band_t band;
+ uint32_t step;
+
+ if(value) {
+ if(!strcasecmp(value, "AM")) {
+ band = BAND_AM;
+ valid = 1;
+ } else if(!strcasecmp(value, "FM")) {
+ band = BAND_FM;
+ valid = 1;
+ } else {
+ char *p;
+ band = strtoul(value, &p, 10);
+ if(p != value && *p == '\0') {
+ switch(band) {
+ case BAND_AM:
+ case BAND_FM:
+ valid = 1;
+ break;
+ default:
+ break;
+ }
+ }
+ }
+ }
+ if(!valid) {
+ afb_req_fail(request, "failed", "Invalid band");
+ return;
+ }
+ ret_json = json_object_new_object();
+ step = radio_impl_get_frequency_step(band);
+ json_object_object_add(ret_json, "step", json_object_new_int((int32_t) step));
+ afb_req_success(request, ret_json, NULL);
+}
+
+/*
+ * @brief Start radio playback
+ *
+ * @param struct afb_req : an afb request structure
+ *
+ */
+static void start(struct afb_req request)
+{
+ radio_impl_start();
+ afb_req_success(request, NULL, NULL);
+}
+
+/*
+ * @brief Stop radio playback
+ *
+ * @param struct afb_req : an afb request structure
+ *
+ */
+static void stop(struct afb_req request)
+{
+ radio_impl_stop();
+ afb_req_success(request, NULL, NULL);
+}
+
+/*
+ * @brief Scan for a station in the specified direction
+ *
+ * @param struct afb_req : an afb request structure
+ *
+ */
+static void scan_start(struct afb_req request)
+{
+ json_object *ret_json;
+ const char *value = afb_req_value(request, "direction");
+ int valid = 0;
+ radio_scan_direction_t direction;
+
+ if(value) {
+ if(!strcasecmp(value, "forward")) {
+ direction = SCAN_FORWARD;
+ valid = 1;
+ } else if(!strcasecmp(value, "backward")) {
+ direction = SCAN_BACKWARD;
+ valid = 1;
+ } else {
+ char *p;
+ direction = strtoul(value, &p, 10);
+ if(p != value && *p == '\0') {
+ switch(direction) {
+ case SCAN_FORWARD:
+ case SCAN_BACKWARD:
+ valid = 1;
+ break;
+ default:
+ break;
+ }
+ }
+ }
+ }
+ if(!valid) {
+ afb_req_fail(request, "failed", "Invalid direction");
+ return;
+ }
+ radio_impl_scan_start(direction, scan_callback, NULL);
+ afb_req_success(request, ret_json, NULL);
+}
+
+/*
+ * @brief Stop station scan
+ *
+ * @param struct afb_req : an afb request structure
+ *
+ */
+static void scan_stop(struct afb_req request)
+{
+ radio_impl_scan_stop();
+ afb_req_success(request, NULL, NULL);
+}
+
+/*
+ * @brief Get (and optionally set) stereo mode
+ *
+ * @param struct afb_req : an afb request structure
+ *
+ */
+static void stereo_mode(struct afb_req request)
+{
+ json_object *ret_json;
+ const char *value = afb_req_value(request, "value");
+ int valid = 0;
+ radio_stereo_mode_t mode;
+ char mode_name[4];
+
+ if(value) {
+ if(!strcasecmp(value, "mono")) {
+ mode = MONO;
+ valid = 1;
+ } else if(!strcasecmp(value, "stereo")) {
+ mode = STEREO;
+ valid = 1;
+ } else {
+ char *p;
+ mode = strtoul(value, &p, 10);
+ if(p != value && *p == '\0') {
+ switch(mode) {
+ case MONO:
+ case STEREO:
+ valid = 1;
+ break;
+ default:
+ break;
+ }
+ }
+ }
+ if(valid) {
+ radio_impl_set_stereo_mode(mode);
+ } else {
+ afb_req_fail(request, "failed", "Invalid mode");
+ return;
+ }
+ }
+ ret_json = json_object_new_object();
+ mode = radio_impl_get_stereo_mode();
+ sprintf(mode_name, "%s", mode == MONO ? "mono" : "stereo");
+ json_object_object_add(ret_json, "mode", json_object_new_string(mode_name));
+ afb_req_success(request, ret_json, NULL);
+}
+
+/*
+ * @brief Subscribe for an event
+ *
+ * @param struct afb_req : an afb request structure
+ *
+ */
+static void subscribe(struct afb_req request)
+{
+ const char *value = afb_req_value(request, "value");
+ if(value) {
+ if(!strcasecmp(value, "frequency")) {
+ afb_req_subscribe(request, freq_event);
+ } else if(!strcasecmp(value, "station_found")) {
+ afb_req_subscribe(request, scan_event);
+ } else {
+ afb_req_fail(request, "failed", "Invalid event");
+ return;
+ }
+ }
+ afb_req_success(request, NULL, NULL);
+}
+
+/*
+ * @brief Unsubscribe for an event
+ *
+ * @param struct afb_req : an afb request structure
+ *
+ */
+static void unsubscribe(struct afb_req request)
+{
+ const char *value = afb_req_value(request, "value");
+ if(value) {
+ if(!strcasecmp(value, "frequency")) {
+ afb_req_unsubscribe(request, freq_event);
+ } else if(!strcasecmp(value, "station_found")) {
+ afb_req_unsubscribe(request, scan_event);
+ } else {
+ afb_req_fail(request, "failed", "Invalid event");
+ return;
+ }
+ }
+ afb_req_success(request, NULL, NULL);
+}
+
+static const struct afb_verb_desc_v1 verbs[]= {
+ { "frequency", AFB_SESSION_CHECK, frequency, "Get/Set frequency" },
+ { "band", AFB_SESSION_CHECK, band, "Get/Set band" },
+ { "band_supported", AFB_SESSION_CHECK, band_supported, "Check band support" },
+ { "frequency_range", AFB_SESSION_CHECK, frequency_range, "Get frequency range" },
+ { "frequency_step", AFB_SESSION_CHECK, frequency_step, "Get frequency step" },
+ { "start", AFB_SESSION_CHECK, start, "Start radio playback" },
+ { "stop", AFB_SESSION_CHECK, stop, "Stop radio playback" },
+ { "scan_start", AFB_SESSION_CHECK, scan_start, "Start station scan" },
+ { "scan_stop", AFB_SESSION_CHECK, scan_stop, "Stop station scan" },
+ { "stereo_mode", AFB_SESSION_CHECK, stereo_mode, "Get/Set stereo_mode" },
+ { "subscribe", AFB_SESSION_CHECK, subscribe, "Subscribe for an event" },
+ { "unsubscribe", AFB_SESSION_CHECK, unsubscribe, "Unsubscribe for an event" },
+ { NULL }
+};
+
+static const struct afb_binding binding_desc = {
+ .type = AFB_BINDING_VERSION_1,
+ .v1 = {
+ .info = "radio service",
+ .prefix = "radio",
+ .verbs = verbs
+ }
+};
+
+const struct afb_binding *afbBindingV1Register (const struct afb_binding_interface *itf)
+{
+ interface = itf;
+
+ return &binding_desc;
+}
+
+int afbBindingV1ServiceInit(struct afb_service service)
+{
+ int rc;
+
+ freq_event = afb_daemon_make_event(interface->daemon, "frequency");
+ scan_event = afb_daemon_make_event(interface->daemon, "station_found");
+
+ rc = radio_impl_init();
+ if(rc == 0) {
+ radio_impl_set_frequency_callback(freq_callback, NULL);
+ }
+
+ return rc;
+}
diff --git a/radio_impl.h b/radio_impl.h
new file mode 100644
index 0000000..79e91a4
--- /dev/null
+++ b/radio_impl.h
@@ -0,0 +1,76 @@
+/*
+ * Copyright (C) 2017 Konsulko Group
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef _RADIO_IMPL_H
+#define _RADIO_IMPL_H
+
+#include <stdint.h>
+
+typedef enum {
+ BAND_AM = 0,
+ BAND_FM
+} radio_band_t;
+
+typedef enum {
+ SCAN_FORWARD = 0,
+ SCAN_BACKWARD
+} radio_scan_direction_t;
+
+typedef void (*radio_scan_callback_t)(uint32_t frequency, void *data);
+
+typedef void (*radio_freq_callback_t)(uint32_t frequency, void *data);
+
+typedef enum {
+ MONO = 0,
+ STEREO
+} radio_stereo_mode_t;
+
+int radio_impl_init(void);
+
+uint32_t radio_impl_get_frequency(void);
+
+void radio_impl_set_frequency(uint32_t frequency);
+
+void radio_impl_set_frequency_callback(radio_freq_callback_t callback,
+ void *data);
+
+radio_band_t radio_impl_get_band(void);
+
+void radio_impl_set_band(radio_band_t band);
+
+int radio_impl_band_supported(radio_band_t band);
+
+uint32_t radio_impl_get_min_frequency(radio_band_t band);
+
+uint32_t radio_impl_get_max_frequency(radio_band_t band);
+
+uint32_t radio_impl_get_frequency_step(radio_band_t band);
+
+void radio_impl_start(void);
+
+void radio_impl_stop(void);
+
+void radio_impl_scan_start(radio_scan_direction_t direction,
+ radio_scan_callback_t callback,
+ void *data);
+
+void radio_impl_scan_stop(void);
+
+radio_stereo_mode_t radio_impl_get_stereo_mode(void);
+
+void radio_impl_set_stereo_mode(radio_stereo_mode_t mode);
+
+#endif /* _RADIO_IMPL_H */
diff --git a/radio_impl_rtlsdr.c b/radio_impl_rtlsdr.c
new file mode 100644
index 0000000..4364fd5
--- /dev/null
+++ b/radio_impl_rtlsdr.c
@@ -0,0 +1,254 @@
+/*
+ * Copyright (C) 2017 Konsulko Group
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdint.h>
+#include <stdbool.h>
+#include <string.h>
+#include <glib.h>
+
+#include "radio_impl.h"
+#include "radio_output.h"
+#include "rtl_fm.h"
+
+// Structure to describe FM band plans, all values in Hz.
+typedef struct {
+ char *name;
+ uint32_t min;
+ uint32_t max;
+ uint32_t step;
+} fm_band_plan_t;
+
+static fm_band_plan_t known_fm_band_plans[5] = {
+ { .name = "US", .min = 87900000, .max = 107900000, .step = 200000 },
+ { .name = "JP", .min = 76100000, .max = 89900000, .step = 100000 },
+ { .name = "EU", .min = 87500000, .max = 108000000, .step = 50000 },
+ { .name = "ITU-1", .min = 87500000, .max = 108000000, .step = 50000 },
+ { .name = "ITU-2", .min = 87900000, .max = 107900000, .step = 50000 }
+};
+
+static unsigned int bandplan;
+static bool present;
+static bool active;
+static uint32_t current_frequency;
+
+static void rtl_output_callback(int16_t *result, int result_len, void *ctx)
+{
+ if(active)
+ radio_output_write((char*) result, result_len * 2);
+}
+
+int radio_impl_init(void)
+{
+ GKeyFile* conf_file;
+ int conf_file_present = 0;
+ char *value_str;
+
+ if(present)
+ return -1;
+
+ // Load settings from configuration file if it exists
+ conf_file = g_key_file_new();
+ if(conf_file &&
+ g_key_file_load_from_dirs(conf_file,
+ "AGL.conf",
+ (const gchar**) g_get_system_config_dirs(),
+ NULL,
+ G_KEY_FILE_KEEP_COMMENTS,
+ NULL) == TRUE) {
+ conf_file_present = 1;
+
+ // Set band plan if it is specified
+ value_str = g_key_file_get_string(conf_file,
+ "radio",
+ "fmbandplan",
+ NULL);
+ if(value_str) {
+ unsigned int i;
+ for(i = 0;
+ i < sizeof(known_fm_band_plans) / sizeof(fm_band_plan_t);
+ i++) {
+ if(!strcasecmp(value_str, known_fm_band_plans[i].name)) {
+ bandplan = i;
+ break;
+ }
+ }
+ }
+ }
+ fprintf(stderr, "Using FM Bandplan: %s\n", known_fm_band_plans[bandplan].name);
+
+ current_frequency = radio_impl_get_min_frequency(BAND_FM);
+ if(rtl_fm_init(current_frequency, 200000, 48000, rtl_output_callback, NULL) < 0) {
+ return -1;
+ }
+
+ if(conf_file_present) {
+ GError *error = NULL;
+ int n;
+
+ // Allow over-riding scanning parameters just in case a demo
+ // setup needs to do so to work reliably.
+ n = g_key_file_get_integer(conf_file,
+ "radio",
+ "scan_squelch_level",
+ &error);
+ //error->code != G_KEY_FILE_ERROR_KEY_NOT_FOUND &&
+ //error->code != G_KEY_FILE_ERROR_INVALID_VALUE) {
+ if(!error) {
+ fprintf(stderr, "Scanning squelch level set to %d\n", n);
+ rtl_fm_scan_set_squelch_level(n);
+ }
+
+ error = NULL;
+ n = g_key_file_get_integer(conf_file,
+ "radio",
+ "scan_squelch_limit",
+ &error);
+ if(!error) {
+ fprintf(stderr, "Scanning squelch limit set to %d\n", n);
+ rtl_fm_scan_set_squelch_limit(n);
+ }
+
+ g_key_file_free(conf_file);
+ }
+
+ present = true;
+ return 0;
+}
+
+uint32_t radio_impl_get_frequency(void)
+{
+ return current_frequency;
+}
+
+void radio_impl_set_frequency(uint32_t frequency)
+{
+ if(!present)
+ return;
+
+ if(frequency < known_fm_band_plans[bandplan].min ||
+ frequency > known_fm_band_plans[bandplan].max)
+ return;
+
+ radio_impl_scan_stop();
+ current_frequency = frequency;
+ rtl_fm_set_freq(frequency);
+}
+
+void radio_impl_set_frequency_callback(radio_freq_callback_t callback,
+ void *data)
+{
+ rtl_fm_set_freq_callback(callback, data);
+}
+
+radio_band_t radio_impl_get_band(void)
+{
+ return BAND_FM;
+}
+
+void radio_impl_set_band(radio_band_t band)
+{
+ // We only support FM, so do nothing
+}
+
+int radio_impl_band_supported(radio_band_t band)
+{
+ if(band == BAND_FM)
+ return 1;
+ return 0;
+}
+
+uint32_t radio_impl_get_min_frequency(radio_band_t band)
+{
+ return known_fm_band_plans[bandplan].min;
+}
+
+uint32_t radio_impl_get_max_frequency(radio_band_t band)
+{
+ return known_fm_band_plans[bandplan].max;
+}
+
+uint32_t radio_impl_get_frequency_step(radio_band_t band)
+{
+ uint32_t ret = 0;
+
+ switch (band) {
+ case BAND_AM:
+ ret = 1000; // 1 kHz
+ break;
+ case BAND_FM:
+ ret = known_fm_band_plans[bandplan].step;
+ break;
+ default:
+ break;
+ }
+ return ret;
+}
+
+void radio_impl_start(void)
+{
+ if(!present)
+ return;
+
+ if(!active) {
+ if(radio_output_start() != 0)
+ return;
+
+ rtl_fm_start();
+ active = true;
+ }
+}
+
+void radio_impl_stop(void)
+{
+ if(!present)
+ return;
+
+ if(active) {
+ active = false;
+ radio_output_stop();
+ rtl_fm_stop();
+
+ }
+}
+
+void radio_impl_scan_start(radio_scan_direction_t direction,
+ radio_scan_callback_t callback,
+ void *data)
+{
+ rtl_fm_scan_start(direction == SCAN_FORWARD ? 0 : 1,
+ callback,
+ data,
+ radio_impl_get_frequency_step(BAND_FM),
+ radio_impl_get_min_frequency(BAND_FM),
+ radio_impl_get_max_frequency(BAND_FM));
+}
+
+void radio_impl_scan_stop(void)
+{
+ rtl_fm_scan_stop();
+}
+
+radio_stereo_mode_t radio_impl_get_stereo_mode(void)
+{
+ return STEREO;
+}
+
+void radio_impl_set_stereo_mode(radio_stereo_mode_t mode)
+{
+ // We only support stereo, so do nothing
+}
diff --git a/radio_output.c b/radio_output.c
new file mode 100644
index 0000000..a49687b
--- /dev/null
+++ b/radio_output.c
@@ -0,0 +1,294 @@
+/*
+ * Copyright (C) 2017 Konsulko Group
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <pulse/pulseaudio.h>
+
+#include "radio_output.h"
+#include "rtl_fm.h"
+
+static pa_threaded_mainloop *mainloop;
+static pa_context *context;
+static pa_stream *stream;
+
+static unsigned int extra;
+static int16_t extra_buf[1];
+static unsigned char *output_buf;
+
+static void pa_context_state_cb(pa_context *c, void *data) {
+ pa_operation *o;
+
+ assert(c);
+ switch (pa_context_get_state(c)) {
+ case PA_CONTEXT_CONNECTING:
+ case PA_CONTEXT_AUTHORIZING:
+ case PA_CONTEXT_SETTING_NAME:
+ case PA_CONTEXT_READY:
+ break;
+ case PA_CONTEXT_TERMINATED:
+ pa_threaded_mainloop_stop(mainloop);
+ break;
+ case PA_CONTEXT_FAILED:
+ default:
+ fprintf(stderr, "PA connection failed: %s\n",
+ pa_strerror(pa_context_errno(c)));
+ pa_threaded_mainloop_stop(mainloop);
+ break;
+ }
+ pa_threaded_mainloop_signal(mainloop, 0);
+}
+
+int radio_output_open(void)
+{
+ pa_context *c;
+ pa_mainloop_api *mapi;
+ char *client;
+
+ if(context)
+ return 0;
+
+ if (!(mainloop = pa_threaded_mainloop_new())) {
+ fprintf(stderr, "pa_mainloop_new() failed.\n");
+ return -1;
+ }
+
+ pa_threaded_mainloop_set_name(mainloop, "pa_mainloop");
+ mapi = pa_threaded_mainloop_get_api(mainloop);
+
+ client = pa_xstrdup("radio");
+ if (!(c = pa_context_new(mapi, client))) {
+ fprintf(stderr, "pa_context_new() failed.\n");
+ goto exit;
+ }
+
+ pa_context_set_state_callback(c, pa_context_state_cb, NULL);
+ if (pa_context_connect(c, NULL, 0, NULL) < 0) {
+ fprintf(stderr, "pa_context_connect(): %s", pa_strerror(pa_context_errno(c)));
+ goto exit;
+ }
+
+ if (pa_threaded_mainloop_start(mainloop) < 0) {
+ fprintf(stderr, "pa_mainloop_run() failed.\n");
+ goto exit;
+ }
+
+ context = c;
+
+ extra = 0;
+ output_buf = malloc(sizeof(unsigned char) * RTL_FM_MAXIMUM_BUF_LENGTH);
+
+ return 0;
+
+exit:
+ if (c)
+ pa_context_unref(c);
+
+ if (mainloop)
+ pa_threaded_mainloop_free(mainloop);
+
+ pa_xfree(client);
+ return -1;
+}
+
+int radio_output_start(void)
+{
+ int error = 0;
+ pa_sample_spec *spec;
+
+ if(stream)
+ return 0;
+
+ if(!context) {
+ error = radio_output_open();
+ if(error != 0)
+ return error;
+ }
+
+ while(pa_context_get_state(context) != PA_CONTEXT_READY)
+ pa_threaded_mainloop_wait(mainloop);
+
+ spec = (pa_sample_spec*) calloc(1, sizeof(pa_sample_spec));
+ spec->format = PA_SAMPLE_S16LE;
+ spec->rate = 24000;
+ spec->channels = 2;
+ if (!pa_sample_spec_valid(spec)) {
+ fprintf(stderr, "%s\n",
+ pa_strerror(pa_context_errno(context)));
+ return -1;
+ }
+
+ pa_threaded_mainloop_lock(mainloop);
+ pa_proplist *props = pa_proplist_new();
+ pa_proplist_sets(props, PA_PROP_MEDIA_ROLE, "radio");
+ stream = pa_stream_new_with_proplist(context, "radio-output", spec, 0, props);
+ if(!stream) {
+ fprintf(stderr, "Error creating stream %s\n",
+ pa_strerror(pa_context_errno(context)));
+ pa_proplist_free(props);
+ free(spec);
+ pa_threaded_mainloop_unlock(mainloop);
+ return -1;
+ }
+ pa_proplist_free(props);
+ free(spec);
+
+ if(pa_stream_connect_playback(stream,
+ NULL,
+ NULL,
+ (pa_stream_flags_t) 0,
+ NULL,
+ NULL) < 0) {
+ fprintf(stderr, "Error connecting to PulseAudio : %s\n",
+ pa_strerror(pa_context_errno(context)));
+ pa_stream_unref(stream);
+ stream = NULL;
+ pa_threaded_mainloop_unlock(mainloop);
+ return -1;
+ }
+
+ pa_threaded_mainloop_unlock(mainloop);
+
+ while(pa_stream_get_state(stream) != PA_STREAM_READY)
+ pa_threaded_mainloop_wait(mainloop);
+
+ return error;
+}
+
+void radio_output_stop(void)
+{
+ if(stream) {
+ pa_threaded_mainloop_lock(mainloop);
+
+ pa_stream_set_state_callback(stream, 0, 0);
+ pa_stream_set_write_callback(stream, 0, 0);
+ pa_stream_set_underflow_callback(stream, 0, 0);
+ pa_stream_set_overflow_callback(stream, 0, 0);
+ pa_stream_set_latency_update_callback(stream, 0, 0);
+
+ pa_operation *o = pa_stream_flush(stream, NULL, NULL);
+ if(o)
+ pa_operation_unref(o);
+
+ pa_stream_disconnect(stream);
+ pa_stream_unref(stream);
+ stream = NULL;
+
+ pa_threaded_mainloop_unlock(mainloop);
+ }
+}
+
+void radio_output_suspend(int state)
+{
+ if(stream) {
+ pa_stream_cork(stream, state, NULL, NULL);
+ }
+}
+
+void radio_output_close(void)
+{
+ radio_output_stop();
+
+ if(context) {
+ pa_context_disconnect(context);
+ pa_context_unref(context);
+ context = NULL;
+ }
+
+ if(mainloop) {
+ pa_threaded_mainloop_stop(mainloop);
+ pa_threaded_mainloop_free(mainloop);
+ mainloop = NULL;
+ }
+
+ free(output_buf);
+ output_buf = NULL;
+}
+
+int radio_output_write(void *buf, int len)
+{
+ int rc = -EINVAL;
+ int error;
+ size_t n = len;
+ size_t avail;
+ int samples = len / 2;
+ void *p;
+
+ if(!stream) {
+ return -1;
+ }
+
+ if(!buf) {
+ fprintf(stderr, "Error: buf == null!\n");
+ return rc;
+ }
+
+ pa_threaded_mainloop_lock(mainloop);
+
+ avail = pa_stream_writable_size(stream);
+ if(avail < n) {
+ /*
+ * NOTE: Definitely room for improvement here,but for now just
+ * check for the no space case that happens when the
+ * stream is corked.
+ */
+ if(!avail) {
+ rc = 0;
+ goto exit;
+ }
+ }
+
+ /*
+ * Handle the rtl_fm code giving us an odd number of samples, which
+ * PA does not like. This extra buffer copying approach is not
+ * particularly efficient, but works for now. It looks feasible to
+ * hack in something in the demod and output thread routines in
+ * rtl_fm.c to handle it there if more performance is required.
+ */
+ p = output_buf;
+ if(extra) {
+ memcpy(output_buf, extra_buf, sizeof(int16_t));
+ if((extra + samples) % 2) {
+ // We still have an extra sample, n remains the same, store the extra
+ memcpy(output_buf + sizeof(int16_t), buf, n - 2);
+ memcpy(extra_buf, ((unsigned char*) buf) + n - 2, sizeof(int16_t));
+ } else {
+ // We have an even number of samples, no extra
+ memcpy(output_buf + sizeof(int16_t), buf, n);
+ n += 2;
+ extra = 0;
+ }
+ } else if(samples % 2) {
+ // We have an extra sample, store it, and decrease n
+ n -= 2;
+ memcpy(output_buf + sizeof(int16_t), buf, n);
+ memcpy(extra_buf, ((unsigned char*) buf) + n, sizeof(int16_t));
+ extra = 1;
+ } else {
+ p = buf;
+ }
+
+ if ((rc = pa_stream_write(stream, p, n, NULL, 0, PA_SEEK_RELATIVE)) < 0) {
+ fprintf(stderr, "Error writing %d bytes to PulseAudio : %s\n",
+ n, pa_strerror(pa_context_errno(context)));
+ }
+exit:
+ pa_threaded_mainloop_unlock(mainloop);
+
+ return rc;
+}
diff --git a/radio_output.h b/radio_output.h
new file mode 100644
index 0000000..2192811
--- /dev/null
+++ b/radio_output.h
@@ -0,0 +1,31 @@
+/*
+ * Copyright (C) 2017 Konsulko Group
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef _RADIO_OUTPUT_H
+#define _RADIO_OUTPUT_H
+
+int radio_output_open(void);
+
+int radio_output_start(void);
+
+void radio_output_stop(void);
+
+void radio_output_close(void);
+
+int radio_output_write(void *buf, int len);
+
+#endif /* _RADIO_OUTPUT_H */
+
diff --git a/rtl_fm.c b/rtl_fm.c
new file mode 100644
index 0000000..1c6a6b2
--- /dev/null
+++ b/rtl_fm.c
@@ -0,0 +1,1267 @@
+/*
+ * rtl-sdr, turns your Realtek RTL2832 based DVB dongle into a SDR receiver
+ * Copyright (C) 2012 by Steve Markgraf <steve@steve-m.de>
+ * Copyright (C) 2012 by Hoernchen <la@tfc-server.de>
+ * Copyright (C) 2012 by Kyle Keen <keenerd@gmail.com>
+ * Copyright (C) 2013 by Elias Oenal <EliasOenal@gmail.com>
+ * Copyright (C) 2016, 2017 Konsulko Group
+ *
+ * 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/>.
+ */
+
+/*
+ * Note that this version replaces the standalone main() with separate
+ * init/start/stop API calls to allow building into another application.
+ * Other than removing the separate controller thread and adding an output
+ * function callback, other changes have been kept to a minimum to
+ * potentially allow using other rtl_fm features by modifying rtl_fm_init.
+ *
+ * December 2016, Scott Murray <scott.murray@konsulko.com>
+ */
+
+/*
+ * written because people could not do real time
+ * FM demod on Atom hardware with GNU radio
+ * based on rtl_sdr.c and rtl_tcp.c
+ *
+ * lots of locks, but that is okay
+ * (no many-to-many locks)
+ *
+ * todo:
+ * sanity checks
+ * scale squelch to other input parameters
+ * test all the demodulations
+ * pad output on hop
+ * frequency ranges could be stored better
+ * scaled AM demod amplification
+ * auto-hop after time limit
+ * peak detector to tune onto stronger signals
+ * fifo for active hop frequency
+ * clips
+ * noise squelch
+ * merge stereo patch
+ * merge soft agc patch
+ * merge udp patch
+ * testmode to detect overruns
+ * watchdog to reset bad dongle
+ * fix oversampling
+ */
+
+#include <errno.h>
+#include <signal.h>
+#include <string.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <math.h>
+#include <pthread.h>
+
+#include "rtl-sdr.h"
+#include "rtl_fm.h"
+#include "convenience/convenience.h"
+
+#define DEFAULT_SAMPLE_RATE 24000
+#define DEFAULT_BUF_LENGTH RTL_FM_DEFAULT_BUF_LENGTH
+#define MAXIMUM_OVERSAMPLE RTL_FM_MAXIMUM_OVERSAMPLE
+#define MAXIMUM_BUF_LENGTH RTL_FM_MAXIMUM_BUF_LENGTH
+#define AUTO_GAIN -100
+#define BUFFER_DUMP 4096
+
+#define FREQUENCIES_LIMIT 1000
+
+#define DEFAULT_SQUELCH_LEVEL 140
+#define DEFAULT_CONSEQ_SQUELCH 10
+
+static volatile int do_exit = 0;
+static int lcm_post[17] = {1,1,1,3,1,5,3,7,1,9,5,11,3,13,7,15,1};
+static int ACTUAL_BUF_LENGTH;
+
+static int *atan_lut = NULL;
+static int atan_lut_size = 131072; /* 512 KB */
+static int atan_lut_coef = 8;
+
+struct dongle_state
+{
+ int exit_flag;
+ pthread_t thread;
+ rtlsdr_dev_t *dev;
+ int dev_index;
+ uint32_t freq;
+ uint32_t rate;
+ int gain;
+ uint16_t buf16[MAXIMUM_BUF_LENGTH];
+ uint32_t buf_len;
+ int ppm_error;
+ int offset_tuning;
+ int direct_sampling;
+ int mute;
+ struct demod_state *demod_target;
+};
+
+struct demod_state
+{
+ int exit_flag;
+ pthread_t thread;
+ int16_t lowpassed[MAXIMUM_BUF_LENGTH];
+ int lp_len;
+ int16_t lp_i_hist[10][6];
+ int16_t lp_q_hist[10][6];
+ int16_t result[MAXIMUM_BUF_LENGTH];
+ int16_t droop_i_hist[9];
+ int16_t droop_q_hist[9];
+ int result_len;
+ int rate_in;
+ int rate_out;
+ int rate_out2;
+ int now_r, now_j;
+ int pre_r, pre_j;
+ int prev_index;
+ int downsample; /* min 1, max 256 */
+ int post_downsample;
+ int output_scale;
+ int squelch_level, conseq_squelch, squelch_hits, terminate_on_squelch;
+ int downsample_passes;
+ int comp_fir_size;
+ int custom_atan;
+ int deemph, deemph_a;
+ int now_lpr;
+ int prev_lpr_index;
+ int dc_block, dc_avg;
+ void (*mode_demod)(struct demod_state*);
+ pthread_rwlock_t rw;
+ pthread_cond_t ready;
+ pthread_mutex_t ready_m;
+ struct output_state *output_target;
+};
+
+struct output_state
+{
+ int exit_flag;
+ pthread_t thread;
+ rtl_fm_output_fn_t output_fn;
+ void *output_fn_data;
+ int16_t result[MAXIMUM_BUF_LENGTH];
+ int result_len;
+ int rate;
+ pthread_rwlock_t rw;
+ pthread_cond_t ready;
+ pthread_mutex_t ready_m;
+};
+
+struct controller_state
+{
+ int exit_flag;
+ pthread_t thread;
+ uint32_t freqs[FREQUENCIES_LIMIT];
+ int freq_len;
+ int freq_now;
+ int edge;
+ int wb_mode;
+ pthread_cond_t hop;
+ pthread_mutex_t hop_m;
+
+ void (*freq_callback)(uint32_t, void*);
+ void *freq_callback_data;
+
+ int scanning;
+ int scan_direction;
+ void (*scan_callback)(uint32_t, void*);
+ void *scan_callback_data;
+ uint32_t scan_step;
+ uint32_t scan_min;
+ uint32_t scan_max;
+ int scan_squelch_level;
+ int scan_squelch_count;
+};
+
+// multiple of these, eventually
+struct dongle_state dongle;
+struct demod_state demod;
+struct output_state output;
+struct controller_state controller;
+
+#if 0
+static void sighandler(int signum)
+{
+ fprintf(stderr, "Signal caught, exiting!\n");
+ do_exit = 1;
+ rtlsdr_cancel_async(dongle.dev);
+}
+#endif
+
+/* more cond dumbness */
+#define safe_cond_signal(n, m) pthread_mutex_lock(m); pthread_cond_signal(n); pthread_mutex_unlock(m)
+#define safe_cond_wait(n, m) pthread_mutex_lock(m); pthread_cond_wait(n, m); pthread_mutex_unlock(m)
+
+/* {length, coef, coef, coef} and scaled by 2^15
+ for now, only length 9, optimal way to get +85% bandwidth */
+#define CIC_TABLE_MAX 10
+int cic_9_tables[][10] = {
+ {0,},
+ {9, -156, -97, 2798, -15489, 61019, -15489, 2798, -97, -156},
+ {9, -128, -568, 5593, -24125, 74126, -24125, 5593, -568, -128},
+ {9, -129, -639, 6187, -26281, 77511, -26281, 6187, -639, -129},
+ {9, -122, -612, 6082, -26353, 77818, -26353, 6082, -612, -122},
+ {9, -120, -602, 6015, -26269, 77757, -26269, 6015, -602, -120},
+ {9, -120, -582, 5951, -26128, 77542, -26128, 5951, -582, -120},
+ {9, -119, -580, 5931, -26094, 77505, -26094, 5931, -580, -119},
+ {9, -119, -578, 5921, -26077, 77484, -26077, 5921, -578, -119},
+ {9, -119, -577, 5917, -26067, 77473, -26067, 5917, -577, -119},
+ {9, -199, -362, 5303, -25505, 77489, -25505, 5303, -362, -199},
+};
+
+void rotate_90(unsigned char *buf, uint32_t len)
+/* 90 rotation is 1+0j, 0+1j, -1+0j, 0-1j
+ or [0, 1, -3, 2, -4, -5, 7, -6] */
+{
+ uint32_t i;
+ unsigned char tmp;
+ for (i=0; i<len; i+=8) {
+ /* uint8_t negation = 255 - x */
+ tmp = 255 - buf[i+3];
+ buf[i+3] = buf[i+2];
+ buf[i+2] = tmp;
+
+ buf[i+4] = 255 - buf[i+4];
+ buf[i+5] = 255 - buf[i+5];
+
+ tmp = 255 - buf[i+6];
+ buf[i+6] = buf[i+7];
+ buf[i+7] = tmp;
+ }
+}
+
+void low_pass(struct demod_state *d)
+/* simple square window FIR */
+{
+ int i=0, i2=0;
+ while (i < d->lp_len) {
+ d->now_r += d->lowpassed[i];
+ d->now_j += d->lowpassed[i+1];
+ i += 2;
+ d->prev_index++;
+ if (d->prev_index < d->downsample) {
+ continue;
+ }
+ d->lowpassed[i2] = d->now_r; // * d->output_scale;
+ d->lowpassed[i2+1] = d->now_j; // * d->output_scale;
+ d->prev_index = 0;
+ d->now_r = 0;
+ d->now_j = 0;
+ i2 += 2;
+ }
+ d->lp_len = i2;
+}
+
+int low_pass_simple(int16_t *signal2, int len, int step)
+// no wrap around, length must be multiple of step
+{
+ int i, i2, sum;
+ for(i=0; i < len; i+=step) {
+ sum = 0;
+ for(i2=0; i2<step; i2++) {
+ sum += (int)signal2[i + i2];
+ }
+ //signal2[i/step] = (int16_t)(sum / step);
+ signal2[i/step] = (int16_t)(sum);
+ }
+ signal2[i/step + 1] = signal2[i/step];
+ return len / step;
+}
+
+void low_pass_real(struct demod_state *s)
+/* simple square window FIR */
+// add support for upsampling?
+{
+ int i=0, i2=0;
+ int fast = (int)s->rate_out;
+ int slow = s->rate_out2;
+ while (i < s->result_len) {
+ s->now_lpr += s->result[i];
+ i++;
+ s->prev_lpr_index += slow;
+ if (s->prev_lpr_index < fast) {
+ continue;
+ }
+ s->result[i2] = (int16_t)(s->now_lpr / (fast/slow));
+ s->prev_lpr_index -= fast;
+ s->now_lpr = 0;
+ i2 += 1;
+ }
+ s->result_len = i2;
+}
+
+void fifth_order(int16_t *data, int length, int16_t *hist)
+/* for half of interleaved data */
+{
+ int i;
+ int16_t a, b, c, d, e, f;
+ a = hist[1];
+ b = hist[2];
+ c = hist[3];
+ d = hist[4];
+ e = hist[5];
+ f = data[0];
+ /* a downsample should improve resolution, so don't fully shift */
+ data[0] = (a + (b+e)*5 + (c+d)*10 + f) >> 4;
+ for (i=4; i<length; i+=4) {
+ a = c;
+ b = d;
+ c = e;
+ d = f;
+ e = data[i-2];
+ f = data[i];
+ data[i/2] = (a + (b+e)*5 + (c+d)*10 + f) >> 4;
+ }
+ /* archive */
+ hist[0] = a;
+ hist[1] = b;
+ hist[2] = c;
+ hist[3] = d;
+ hist[4] = e;
+ hist[5] = f;
+}
+
+void generic_fir(int16_t *data, int length, int *fir, int16_t *hist)
+/* Okay, not at all generic. Assumes length 9, fix that eventually. */
+{
+ int d, temp, sum;
+ for (d=0; d<length; d+=2) {
+ temp = data[d];
+ sum = 0;
+ sum += (hist[0] + hist[8]) * fir[1];
+ sum += (hist[1] + hist[7]) * fir[2];
+ sum += (hist[2] + hist[6]) * fir[3];
+ sum += (hist[3] + hist[5]) * fir[4];
+ sum += hist[4] * fir[5];
+ data[d] = sum >> 15 ;
+ hist[0] = hist[1];
+ hist[1] = hist[2];
+ hist[2] = hist[3];
+ hist[3] = hist[4];
+ hist[4] = hist[5];
+ hist[5] = hist[6];
+ hist[6] = hist[7];
+ hist[7] = hist[8];
+ hist[8] = temp;
+ }
+}
+
+/* define our own complex math ops
+ because ARMv5 has no hardware float */
+
+void multiply(int ar, int aj, int br, int bj, int *cr, int *cj)
+{
+ *cr = ar*br - aj*bj;
+ *cj = aj*br + ar*bj;
+}
+
+int polar_discriminant(int ar, int aj, int br, int bj)
+{
+ int cr, cj;
+ double angle;
+ multiply(ar, aj, br, -bj, &cr, &cj);
+ angle = atan2((double)cj, (double)cr);
+ return (int)(angle / 3.14159 * (1<<14));
+}
+
+int fast_atan2(int y, int x)
+/* pre scaled for int16 */
+{
+ int yabs, angle;
+ int pi4=(1<<12), pi34=3*(1<<12); // note pi = 1<<14
+ if (x==0 && y==0) {
+ return 0;
+ }
+ yabs = y;
+ if (yabs < 0) {
+ yabs = -yabs;
+ }
+ if (x >= 0) {
+ angle = pi4 - pi4 * (x-yabs) / (x+yabs);
+ } else {
+ angle = pi34 - pi4 * (x+yabs) / (yabs-x);
+ }
+ if (y < 0) {
+ return -angle;
+ }
+ return angle;
+}
+
+int polar_disc_fast(int ar, int aj, int br, int bj)
+{
+ int cr, cj;
+ multiply(ar, aj, br, -bj, &cr, &cj);
+ return fast_atan2(cj, cr);
+}
+
+int atan_lut_init(void)
+{
+ int i = 0;
+
+ atan_lut = malloc(atan_lut_size * sizeof(int));
+
+ for (i = 0; i < atan_lut_size; i++) {
+ atan_lut[i] = (int) (atan((double) i / (1<<atan_lut_coef)) / 3.14159 * (1<<14));
+ }
+
+ return 0;
+}
+
+int polar_disc_lut(int ar, int aj, int br, int bj)
+{
+ int cr, cj, x, x_abs;
+
+ multiply(ar, aj, br, -bj, &cr, &cj);
+
+ /* special cases */
+ if (cr == 0 || cj == 0) {
+ if (cr == 0 && cj == 0)
+ {return 0;}
+ if (cr == 0 && cj > 0)
+ {return 1 << 13;}
+ if (cr == 0 && cj < 0)
+ {return -(1 << 13);}
+ if (cj == 0 && cr > 0)
+ {return 0;}
+ if (cj == 0 && cr < 0)
+ {return 1 << 14;}
+ }
+
+ /* real range -32768 - 32768 use 64x range -> absolute maximum: 2097152 */
+ x = (cj << atan_lut_coef) / cr;
+ x_abs = abs(x);
+
+ if (x_abs >= atan_lut_size) {
+ /* we can use linear range, but it is not necessary */
+ return (cj > 0) ? 1<<13 : -1<<13;
+ }
+
+ if (x > 0) {
+ return (cj > 0) ? atan_lut[x] : atan_lut[x] - (1<<14);
+ } else {
+ return (cj > 0) ? (1<<14) - atan_lut[-x] : -atan_lut[-x];
+ }
+
+ return 0;
+}
+
+void fm_demod(struct demod_state *fm)
+{
+ int i, pcm;
+ int16_t *lp = fm->lowpassed;
+ pcm = polar_discriminant(lp[0], lp[1],
+ fm->pre_r, fm->pre_j);
+ fm->result[0] = (int16_t)pcm;
+ for (i = 2; i < (fm->lp_len-1); i += 2) {
+ switch (fm->custom_atan) {
+ case 0:
+ pcm = polar_discriminant(lp[i], lp[i+1],
+ lp[i-2], lp[i-1]);
+ break;
+ case 1:
+ pcm = polar_disc_fast(lp[i], lp[i+1],
+ lp[i-2], lp[i-1]);
+ break;
+ case 2:
+ pcm = polar_disc_lut(lp[i], lp[i+1],
+ lp[i-2], lp[i-1]);
+ break;
+ }
+ fm->result[i/2] = (int16_t)pcm;
+ }
+ fm->pre_r = lp[fm->lp_len - 2];
+ fm->pre_j = lp[fm->lp_len - 1];
+ fm->result_len = fm->lp_len/2;
+}
+
+void am_demod(struct demod_state *fm)
+// todo, fix this extreme laziness
+{
+ int i, pcm;
+ int16_t *lp = fm->lowpassed;
+ int16_t *r = fm->result;
+ for (i = 0; i < fm->lp_len; i += 2) {
+ // hypot uses floats but won't overflow
+ //r[i/2] = (int16_t)hypot(lp[i], lp[i+1]);
+ pcm = lp[i] * lp[i];
+ pcm += lp[i+1] * lp[i+1];
+ r[i/2] = (int16_t)sqrt(pcm) * fm->output_scale;
+ }
+ fm->result_len = fm->lp_len/2;
+ // lowpass? (3khz) highpass? (dc)
+}
+
+void usb_demod(struct demod_state *fm)
+{
+ int i, pcm;
+ int16_t *lp = fm->lowpassed;
+ int16_t *r = fm->result;
+ for (i = 0; i < fm->lp_len; i += 2) {
+ pcm = lp[i] + lp[i+1];
+ r[i/2] = (int16_t)pcm * fm->output_scale;
+ }
+ fm->result_len = fm->lp_len/2;
+}
+
+void lsb_demod(struct demod_state *fm)
+{
+ int i, pcm;
+ int16_t *lp = fm->lowpassed;
+ int16_t *r = fm->result;
+ for (i = 0; i < fm->lp_len; i += 2) {
+ pcm = lp[i] - lp[i+1];
+ r[i/2] = (int16_t)pcm * fm->output_scale;
+ }
+ fm->result_len = fm->lp_len/2;
+}
+
+void raw_demod(struct demod_state *fm)
+{
+ int i;
+ for (i = 0; i < fm->lp_len; i++) {
+ fm->result[i] = (int16_t)fm->lowpassed[i];
+ }
+ fm->result_len = fm->lp_len;
+}
+
+void deemph_filter(struct demod_state *fm)
+{
+ static int avg; // cheating...
+ int i, d;
+ // de-emph IIR
+ // avg = avg * (1 - alpha) + sample * alpha;
+ for (i = 0; i < fm->result_len; i++) {
+ d = fm->result[i] - avg;
+ if (d > 0) {
+ avg += (d + fm->deemph_a/2) / fm->deemph_a;
+ } else {
+ avg += (d - fm->deemph_a/2) / fm->deemph_a;
+ }
+ fm->result[i] = (int16_t)avg;
+ }
+}
+
+void dc_block_filter(struct demod_state *fm)
+{
+ int i, avg;
+ int64_t sum = 0;
+ for (i=0; i < fm->result_len; i++) {
+ sum += fm->result[i];
+ }
+ avg = sum / fm->result_len;
+ avg = (avg + fm->dc_avg * 9) / 10;
+ for (i=0; i < fm->result_len; i++) {
+ fm->result[i] -= avg;
+ }
+ fm->dc_avg = avg;
+}
+
+int mad(int16_t *samples, int len, int step)
+/* mean average deviation */
+{
+ int i=0, sum=0, ave=0;
+ if (len == 0)
+ {return 0;}
+ for (i=0; i<len; i+=step) {
+ sum += samples[i];
+ }
+ ave = sum / (len * step);
+ sum = 0;
+ for (i=0; i<len; i+=step) {
+ sum += abs(samples[i] - ave);
+ }
+ return sum / (len / step);
+}
+
+int rms(int16_t *samples, int len, int step)
+/* largely lifted from rtl_power */
+{
+ int i;
+ long p, t, s;
+ double dc, err;
+
+ p = t = 0L;
+ for (i=0; i<len; i+=step) {
+ s = (long)samples[i];
+ t += s;
+ p += s * s;
+ }
+ /* correct for dc offset in squares */
+ dc = (double)(t*step) / (double)len;
+ err = t * 2 * dc - dc * dc * len;
+
+ return (int)sqrt((p-err) / len);
+}
+
+void arbitrary_upsample(int16_t *buf1, int16_t *buf2, int len1, int len2)
+/* linear interpolation, len1 < len2 */
+{
+ int i = 1;
+ int j = 0;
+ int tick = 0;
+ double frac; // use integers...
+ while (j < len2) {
+ frac = (double)tick / (double)len2;
+ buf2[j] = (int16_t)(buf1[i-1]*(1-frac) + buf1[i]*frac);
+ j++;
+ tick += len1;
+ if (tick > len2) {
+ tick -= len2;
+ i++;
+ }
+ if (i >= len1) {
+ i = len1 - 1;
+ tick = len2;
+ }
+ }
+}
+
+void arbitrary_downsample(int16_t *buf1, int16_t *buf2, int len1, int len2)
+/* fractional boxcar lowpass, len1 > len2 */
+{
+ int i = 1;
+ int j = 0;
+ int tick = 0;
+ double remainder = 0;
+ double frac; // use integers...
+ buf2[0] = 0;
+ while (j < len2) {
+ frac = 1.0;
+ if ((tick + len2) > len1) {
+ frac = (double)(len1 - tick) / (double)len2;}
+ buf2[j] += (int16_t)((double)buf1[i] * frac + remainder);
+ remainder = (double)buf1[i] * (1.0-frac);
+ tick += len2;
+ i++;
+ if (tick > len1) {
+ j++;
+ buf2[j] = 0;
+ tick -= len1;
+ }
+ if (i >= len1) {
+ i = len1 - 1;
+ tick = len1;
+ }
+ }
+ for (j=0; j<len2; j++) {
+ buf2[j] = buf2[j] * len2 / len1;}
+}
+
+void arbitrary_resample(int16_t *buf1, int16_t *buf2, int len1, int len2)
+/* up to you to calculate lengths and make sure it does not go OOB
+ * okay for buffers to overlap, if you are downsampling */
+{
+ if (len1 < len2) {
+ arbitrary_upsample(buf1, buf2, len1, len2);
+ } else {
+ arbitrary_downsample(buf1, buf2, len1, len2);
+ }
+}
+
+void full_demod(struct demod_state *d)
+{
+ int i, ds_p;
+ int sr = 0;
+ ds_p = d->downsample_passes;
+ if (ds_p) {
+ for (i=0; i < ds_p; i++) {
+ fifth_order(d->lowpassed, (d->lp_len >> i), d->lp_i_hist[i]);
+ fifth_order(d->lowpassed+1, (d->lp_len >> i) - 1, d->lp_q_hist[i]);
+ }
+ d->lp_len = d->lp_len >> ds_p;
+ /* droop compensation */
+ if (d->comp_fir_size == 9 && ds_p <= CIC_TABLE_MAX) {
+ generic_fir(d->lowpassed, d->lp_len,
+ cic_9_tables[ds_p], d->droop_i_hist);
+ generic_fir(d->lowpassed+1, d->lp_len-1,
+ cic_9_tables[ds_p], d->droop_q_hist);
+ }
+ } else {
+ low_pass(d);
+ }
+ /* power squelch */
+ if (d->squelch_level) {
+ sr = rms(d->lowpassed, d->lp_len, 1);
+ if (sr < d->squelch_level) {
+ d->squelch_hits++;
+ for (i=0; i< d->lp_len; i++) {
+ d->lowpassed[i] = 0;
+ }
+ } else {
+ d->squelch_hits = 0;
+ }
+ }
+ d->mode_demod(d); /* lowpassed -> result */
+ if (d->mode_demod == &raw_demod) {
+ return;
+ }
+ /* todo, fm noise squelch */
+ // use nicer filter here too?
+ if (d->post_downsample > 1) {
+ d->result_len = low_pass_simple(d->result, d->result_len, d->post_downsample);}
+ if (d->deemph) {
+ deemph_filter(d);}
+ if (d->dc_block) {
+ dc_block_filter(d);}
+ if (d->rate_out2 > 0) {
+ low_pass_real(d);
+ //arbitrary_resample(d->result, d->result, d->result_len, d->result_len * d->rate_out2 / d->rate_out);
+ }
+}
+
+static void rtlsdr_callback(unsigned char *buf, uint32_t len, void *ctx)
+{
+ int i;
+ struct dongle_state *s = ctx;
+ struct demod_state *d = s->demod_target;
+
+ if (do_exit) {
+ return;}
+ if (!ctx) {
+ return;}
+ if (s->mute) {
+ for (i=0; i<s->mute; i++) {
+ buf[i] = 127;}
+ s->mute = 0;
+ }
+ if (!s->offset_tuning) {
+ rotate_90(buf, len);}
+ for (i=0; i<(int)len; i++) {
+ s->buf16[i] = (int16_t)buf[i] - 127;}
+ pthread_rwlock_wrlock(&d->rw);
+ memcpy(d->lowpassed, s->buf16, 2*len);
+ d->lp_len = len;
+ pthread_rwlock_unlock(&d->rw);
+ safe_cond_signal(&d->ready, &d->ready_m);
+}
+
+static void *dongle_thread_fn(void *arg)
+{
+ struct dongle_state *s = arg;
+ fprintf(stderr, "dongle_thread_fn running\n");
+ rtlsdr_read_async(s->dev, rtlsdr_callback, s, 0, s->buf_len);
+ fprintf(stderr, "dongle_thread_fn exited!\n");
+ return 0;
+}
+
+static void rtl_fm_scan_callback(void)
+{
+ struct controller_state *s = &controller;
+ uint32_t frequency = rtl_fm_get_freq();
+
+ if(!s->scanning)
+ return;
+
+ if(!s->scan_direction) {
+ frequency += s->scan_step;
+ if(frequency > s->scan_max)
+ frequency = s->scan_min;
+ } else {
+ frequency -= s->scan_step;
+ if(frequency < s->scan_min)
+ frequency = s->scan_max;
+ }
+
+ rtl_fm_set_freq(frequency);
+}
+
+static void rtl_fm_scan_end_callback(void)
+{
+ struct controller_state *s = &controller;
+
+ if(!s->scanning)
+ return;
+
+ rtl_fm_scan_stop();
+
+ if(s->scan_callback)
+ s->scan_callback(rtl_fm_get_freq(), s->scan_callback_data);
+}
+
+static void *demod_thread_fn(void *arg)
+{
+ struct demod_state *d = arg;
+ struct output_state *o = d->output_target;
+ fprintf(stderr, "demod_thread_fn running\n");
+ while (!do_exit) {
+ safe_cond_wait(&d->ready, &d->ready_m);
+ pthread_rwlock_wrlock(&d->rw);
+ full_demod(d);
+ pthread_rwlock_unlock(&d->rw);
+ if (d->exit_flag) {
+ do_exit = 1;
+ }
+ if (d->squelch_level) {
+ if(d->squelch_hits > d->conseq_squelch) {
+ d->squelch_hits = d->conseq_squelch + 1; /* hair trigger */
+ //safe_cond_signal(&controller.hop, &controller.hop_m);
+ rtl_fm_scan_callback();
+ continue;
+ } else if(!d->squelch_hits) {
+ rtl_fm_scan_end_callback();
+ }
+ }
+ pthread_rwlock_wrlock(&o->rw);
+ memcpy(o->result, d->result, 2*d->result_len);
+ o->result_len = d->result_len;
+ pthread_rwlock_unlock(&o->rw);
+ safe_cond_signal(&o->ready, &o->ready_m);
+ }
+ fprintf(stderr, "demod_thread_fn exited!\n");
+ return 0;
+}
+
+static void *output_thread_fn(void *arg)
+{
+ struct output_state *s = arg;
+ fprintf(stderr, "output_thread_fn running\n");
+ while (!do_exit) {
+ // use timedwait and pad out under runs
+ safe_cond_wait(&s->ready, &s->ready_m);
+ pthread_rwlock_rdlock(&s->rw);
+ if(s->output_fn) {
+ s->output_fn(s->result, s->result_len, s->output_fn_data);
+ }
+ pthread_rwlock_unlock(&s->rw);
+ }
+ fprintf(stderr, "output_thread_fn exited!\n");
+ return 0;
+}
+
+static void optimal_settings(int freq, int rate)
+{
+ // giant ball of hacks
+ // seems unable to do a single pass, 2:1
+ int capture_freq, capture_rate;
+ struct dongle_state *d = &dongle;
+ struct demod_state *dm = &demod;
+ struct controller_state *cs = &controller;
+ dm->downsample = (1000000 / dm->rate_in) + 1;
+ if (dm->downsample_passes) {
+ dm->downsample_passes = (int)log2(dm->downsample) + 1;
+ dm->downsample = 1 << dm->downsample_passes;
+ }
+ capture_freq = freq;
+ capture_rate = dm->downsample * dm->rate_in;
+ if (!d->offset_tuning) {
+ capture_freq = freq + capture_rate/4;}
+ capture_freq += cs->edge * dm->rate_in / 2;
+ dm->output_scale = (1<<15) / (128 * dm->downsample);
+ if (dm->output_scale < 1) {
+ dm->output_scale = 1;}
+ if (dm->mode_demod == &fm_demod) {
+ dm->output_scale = 1;}
+ d->freq = (uint32_t)capture_freq;
+ d->rate = (uint32_t)capture_rate;
+}
+
+
+void frequency_range(struct controller_state *s, char *arg)
+{
+ char *start, *stop, *step;
+ int i;
+ start = arg;
+ stop = strchr(start, ':') + 1;
+ stop[-1] = '\0';
+ step = strchr(stop, ':') + 1;
+ step[-1] = '\0';
+ for(i=(int)atofs(start); i<=(int)atofs(stop); i+=(int)atofs(step))
+ {
+ s->freqs[s->freq_len] = (uint32_t)i;
+ s->freq_len++;
+ if (s->freq_len >= FREQUENCIES_LIMIT) {
+ break;}
+ }
+ stop[-1] = ':';
+ step[-1] = ':';
+}
+
+void dongle_init(struct dongle_state *s)
+{
+ s->rate = DEFAULT_SAMPLE_RATE;
+ s->gain = AUTO_GAIN; // tenths of a dB
+ s->mute = 0;
+ s->direct_sampling = 0;
+ s->offset_tuning = 0;
+ s->demod_target = &demod;
+}
+
+void demod_init(struct demod_state *s)
+{
+ s->rate_in = DEFAULT_SAMPLE_RATE;
+ s->rate_out = DEFAULT_SAMPLE_RATE;
+ s->squelch_level = 0;
+ s->conseq_squelch = DEFAULT_CONSEQ_SQUELCH;
+ s->terminate_on_squelch = 0;
+ s->squelch_hits = DEFAULT_CONSEQ_SQUELCH + 1;
+ s->downsample_passes = 0;
+ s->comp_fir_size = 0;
+ s->prev_index = 0;
+ s->post_downsample = 1; // once this works, default = 4
+ s->custom_atan = 0;
+ s->deemph = 0;
+ s->rate_out2 = -1; // flag for disabled
+ s->mode_demod = &fm_demod;
+ s->pre_j = s->pre_r = s->now_r = s->now_j = 0;
+ s->prev_lpr_index = 0;
+ s->deemph_a = 0;
+ s->now_lpr = 0;
+ s->dc_block = 0;
+ s->dc_avg = 0;
+ pthread_rwlock_init(&s->rw, NULL);
+ pthread_cond_init(&s->ready, NULL);
+ pthread_mutex_init(&s->ready_m, NULL);
+ s->output_target = &output;
+}
+
+void demod_cleanup(struct demod_state *s)
+{
+ pthread_rwlock_destroy(&s->rw);
+ pthread_cond_destroy(&s->ready);
+ pthread_mutex_destroy(&s->ready_m);
+}
+
+void output_init(struct output_state *s)
+{
+ s->rate = DEFAULT_SAMPLE_RATE;
+ s->output_fn = NULL;
+ s->output_fn_data = NULL;
+ pthread_rwlock_init(&s->rw, NULL);
+ pthread_cond_init(&s->ready, NULL);
+ pthread_mutex_init(&s->ready_m, NULL);
+}
+
+void output_cleanup(struct output_state *s)
+{
+ pthread_rwlock_destroy(&s->rw);
+ pthread_cond_destroy(&s->ready);
+ pthread_mutex_destroy(&s->ready_m);
+}
+
+void controller_init(struct controller_state *s)
+{
+ s->freqs[0] = 100000000;
+ s->freq_len = 0;
+ s->edge = 0;
+ s->wb_mode = 0;
+ pthread_cond_init(&s->hop, NULL);
+ pthread_mutex_init(&s->hop_m, NULL);
+}
+
+void controller_cleanup(struct controller_state *s)
+{
+ pthread_cond_destroy(&s->hop);
+ pthread_mutex_destroy(&s->hop_m);
+}
+
+void sanity_checks(void)
+{
+ if (controller.freq_len == 0) {
+ fprintf(stderr, "Please specify a frequency.\n");
+ exit(1);
+ }
+
+ if (controller.freq_len >= FREQUENCIES_LIMIT) {
+ fprintf(stderr, "Too many channels, maximum %i.\n", FREQUENCIES_LIMIT);
+ exit(1);
+ }
+
+ if (controller.freq_len > 1 && demod.squelch_level == 0) {
+ fprintf(stderr, "Please specify a squelch level. Required for scanning multiple frequencies.\n");
+ exit(1);
+ }
+
+}
+
+int rtl_fm_init(uint32_t freq,
+ uint32_t sample_rate,
+ uint32_t resample_rate,
+ rtl_fm_output_fn_t output_fn,
+ void *output_fn_data)
+{
+ int r = 0;
+
+ dongle_init(&dongle);
+ demod_init(&demod);
+ output_init(&output);
+ controller_init(&controller);
+
+ /*
+ * Simulate the effects of command line arguments:
+ *
+ * -W wbfm -s <sample rate> -r <resample rate>
+ */
+
+ /* Set initial frequency */
+ controller.freqs[0] = freq;
+ controller.freq_len++;
+
+ /* Set mode to wbfm */
+ controller.wb_mode = 1;
+ demod.mode_demod = &fm_demod;
+ demod.rate_in = 170000;
+ demod.rate_out = 170000;
+ demod.rate_out2 = 32000;
+ demod.custom_atan = 1;
+ //demod.post_downsample = 4;
+ demod.deemph = 1;
+ controller.scan_squelch_count = DEFAULT_CONSEQ_SQUELCH;
+ controller.scan_squelch_level = DEFAULT_SQUELCH_LEVEL;
+ demod.squelch_level = 0;
+
+ /* Adjust frequency for wb mode */
+ controller.freqs[0] += 16000;
+
+ /* Set sample rate */
+ demod.rate_in = sample_rate;
+ demod.rate_out = sample_rate;
+
+ /* Set resample rate */
+ output.rate = (int) resample_rate;
+ demod.rate_out2 = (int) resample_rate;
+
+ /* Set output function pointer */
+ if(output_fn) {
+ output.output_fn = output_fn;
+ output.output_fn_data = output_fn_data;
+ }
+
+ /* quadruple sample_rate to limit to Δθ to ±π/2 */
+ demod.rate_in *= demod.post_downsample;
+
+ if (!output.rate) {
+ output.rate = demod.rate_out;
+ }
+
+ sanity_checks();
+
+ if (controller.freq_len > 1) {
+ demod.terminate_on_squelch = 0;
+ }
+
+ ACTUAL_BUF_LENGTH = lcm_post[demod.post_downsample] * DEFAULT_BUF_LENGTH;
+
+ dongle.dev_index = verbose_device_search("0");
+ if (dongle.dev_index < 0) {
+ return -1;
+ }
+
+ r = rtlsdr_open(&dongle.dev, (uint32_t)dongle.dev_index);
+ if (r < 0) {
+ fprintf(stderr, "Failed to open rtlsdr device #%d.\n", dongle.dev_index);
+ return r;
+ }
+
+ if (demod.deemph) {
+ demod.deemph_a = (int)round(1.0/((1.0-exp(-1.0/(demod.rate_out * 75e-6)))));
+ }
+
+ /* Set the tuner gain */
+ if (dongle.gain == AUTO_GAIN) {
+ verbose_auto_gain(dongle.dev);
+ } else {
+ dongle.gain = nearest_gain(dongle.dev, dongle.gain);
+ verbose_gain_set(dongle.dev, dongle.gain);
+ }
+
+ verbose_ppm_set(dongle.dev, dongle.ppm_error);
+
+ //r = rtlsdr_set_testmode(dongle.dev, 1);
+
+ return r;
+}
+
+void rtl_fm_start(void)
+{
+ struct controller_state *s = &controller;
+
+ /*
+ * A bunch of the following is pulled from the controller_thread_fn,
+ * which has been removed.
+ */
+
+ /* Reset endpoint before we start reading from it (mandatory) */
+ verbose_reset_buffer(dongle.dev);
+
+ /* set up primary channel */
+ optimal_settings(s->freqs[0], demod.rate_in);
+ if (dongle.direct_sampling) {
+ verbose_direct_sampling(dongle.dev, 1);}
+ if (dongle.offset_tuning) {
+ verbose_offset_tuning(dongle.dev);}
+
+ /* Set the frequency */
+ verbose_set_frequency(dongle.dev, dongle.freq);
+ fprintf(stderr, "Oversampling input by: %ix.\n", demod.downsample);
+ fprintf(stderr, "Oversampling output by: %ix.\n", demod.post_downsample);
+ fprintf(stderr, "Buffer size: %0.2fms\n",
+ 1000 * 0.5 * (float)ACTUAL_BUF_LENGTH / (float)dongle.rate);
+
+ /* Set the sample rate */
+ verbose_set_sample_rate(dongle.dev, dongle.rate);
+ fprintf(stderr, "Output at %u Hz.\n", demod.rate_in/demod.post_downsample);
+ usleep(100000);
+
+ rtl_fm_scan_stop();
+
+ do_exit = 0;
+ pthread_create(&output.thread, NULL, output_thread_fn, (void *)(&output));
+ pthread_create(&demod.thread, NULL, demod_thread_fn, (void *)(&demod));
+ pthread_create(&dongle.thread, NULL, dongle_thread_fn, (void *)(&dongle));
+}
+
+void rtl_fm_set_freq(uint32_t freq)
+{
+ struct controller_state *s = &controller;
+
+ if(s->freqs[0] == freq)
+ return;
+
+ s->freqs[0] = freq;
+ s->freq_len = 1;
+
+ if (s->wb_mode) {
+ s->freqs[0] += 16000;
+ }
+
+ optimal_settings(s->freqs[0], demod.rate_in);
+ if (dongle.offset_tuning) {
+ verbose_offset_tuning(dongle.dev);
+ }
+ rtlsdr_set_center_freq(dongle.dev, dongle.freq);
+
+ // It does not look like refreshing the sample rate is desirable
+ // (e.g. the scanning code in the removed controller thread function
+ // did not do it), and behavior seemed a bit less robust with it
+ // present. However, I am leaving this here as a reminder to revisit
+ // via some more testing.
+ //rtlsdr_set_sample_rate(dongle.dev, dongle.rate);
+
+ // This triggers a mute during the frequency change
+ dongle.mute = BUFFER_DUMP;
+
+ if(s->freq_callback)
+ s->freq_callback(freq, s->freq_callback_data);
+}
+
+void rtl_fm_set_freq_callback(void (*callback)(uint32_t, void *),
+ void *data)
+{
+ struct controller_state *s = &controller;
+
+ s->freq_callback = callback;
+ s->freq_callback_data = data;
+}
+
+uint32_t rtl_fm_get_freq(void)
+{
+ struct controller_state *s = &controller;
+ uint32_t frequency = s->freqs[0];
+
+ if (s->wb_mode)
+ frequency -= 16000;
+
+ return frequency;
+}
+
+void rtl_fm_stop(void)
+{
+ rtl_fm_scan_stop();
+
+ rtlsdr_cancel_async(dongle.dev);
+ do_exit = 1;
+ pthread_join(dongle.thread, NULL);
+ safe_cond_signal(&demod.ready, &demod.ready_m);
+ pthread_join(demod.thread, NULL);
+ safe_cond_signal(&output.ready, &output.ready_m);
+ pthread_join(output.thread, NULL);
+}
+
+void rtl_fm_scan_start(int direction,
+ void (*callback)(uint32_t, void *),
+ void *data,
+ uint32_t step,
+ uint32_t min,
+ uint32_t max)
+{
+ struct controller_state *s = &controller;
+ struct demod_state *dm = &demod;
+ uint32_t frequency = rtl_fm_get_freq();
+
+ if(s->scanning && s->scan_direction == direction)
+ return;
+
+ s->scanning = 1;
+ s->scan_direction = direction;
+ s->scan_callback = callback;
+ s->scan_callback_data = data;
+ s->scan_step = step;
+ s->scan_min = min;
+ s->scan_max = max;
+
+ /* Start scan by stepping in the desired direction */
+ if(!direction) {
+ frequency += s->scan_step;
+ if(frequency > s->scan_max)
+ frequency = s->scan_min;
+ } else {
+ frequency -= s->scan_step;
+ if(frequency < s->scan_min)
+ frequency = s->scan_max;
+ }
+
+ rtl_fm_set_freq(frequency);
+
+ dm->conseq_squelch = s->scan_squelch_count;
+ dm->squelch_hits = s->scan_squelch_count + 1;
+ dm->squelch_level = s->scan_squelch_level;
+}
+
+void rtl_fm_scan_stop(void)
+{
+ struct controller_state *s = &controller;
+ struct demod_state *dm = &demod;
+
+ s->scanning = 0;
+
+ dm->squelch_hits = s->scan_squelch_count + 1;
+ dm->squelch_level = 0;
+}
+
+void rtl_fm_scan_set_squelch_level(int level)
+{
+ struct controller_state *s = &controller;
+
+ s->scan_squelch_level = level;
+}
+
+void rtl_fm_scan_set_squelch_limit(int count)
+{
+ struct controller_state *s = &controller;
+
+ s->scan_squelch_count = count;
+}
+
+void rtl_fm_cleanup(void)
+{
+ //dongle_cleanup(&dongle);
+ demod_cleanup(&demod);
+ output_cleanup(&output);
+ controller_cleanup(&controller);
+
+ rtlsdr_close(dongle.dev);
+}
+
+// vim: tabstop=8:softtabstop=8:shiftwidth=8:noexpandtab
diff --git a/rtl_fm.h b/rtl_fm.h
new file mode 100644
index 0000000..f5b2a86
--- /dev/null
+++ b/rtl_fm.h
@@ -0,0 +1,70 @@
+/*
+ * rtl-sdr, turns your Realtek RTL2832 based DVB dongle into a SDR receiver
+ * Copyright (C) 2016, 2017 Konsulko Group
+ *
+ * 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/>.
+ */
+
+#ifndef RTL_FM_H
+#define RTL_FM_H
+
+#include <stdint.h>
+
+#define RTL_FM_DEFAULT_BUF_LENGTH (1 * 16384)
+#define RTL_FM_MAXIMUM_OVERSAMPLE 16
+#define RTL_FM_MAXIMUM_BUF_LENGTH (RTL_FM_MAXIMUM_OVERSAMPLE * RTL_FM_DEFAULT_BUF_LENGTH)
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+typedef void (*rtl_fm_output_fn_t)(int16_t *result, int result_len, void *data);
+
+int rtl_fm_init(uint32_t freq,
+ uint32_t sample_rate,
+ uint32_t resample_rate,
+ rtl_fm_output_fn_t output_fn,
+ void *output_fn_data);
+
+void rtl_fm_start(void);
+
+void rtl_fm_set_freq(uint32_t freq);
+
+void rtl_fm_set_freq_callback(void (*callback)(uint32_t, void *),
+ void *data);
+
+uint32_t rtl_fm_get_freq(void);
+
+void rtl_fm_stop(void);
+
+void rtl_fm_scan_start(int direction,
+ void (*callback)(uint32_t, void *),
+ void *data,
+ uint32_t step,
+ uint32_t min,
+ uint32_t max);
+
+void rtl_fm_scan_stop(void);
+
+void rtl_fm_scan_set_squelch_level(int level);
+
+void rtl_fm_scan_set_squelch_limit(int count);
+
+void rtl_fm_cleanup(void);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* RTL_FM_H */