-
-#include "local-def.h"
-
-/* -------------- RADIO DEFINITIONS ------------------ */
-
-#include <math.h>
-#include <pthread.h>
-#include <rtl-sdr.h>
-
-#define pthread_signal(n, m) pthread_mutex_lock(m); pthread_cond_signal(n); pthread_mutex_unlock(m)
-#define pthread_wait(n, m) pthread_mutex_lock(m); pthread_cond_wait(n, m); pthread_mutex_unlock(m)
-#define BUF_LEN 16*16384
-
-typedef enum { FM, AM } Mode;
-typedef struct dongle_ctx dongle_ctx;
-typedef struct demod_ctx demod_ctx;
-typedef struct output_ctx output_ctx;
-typedef struct dev_ctx dev_ctx_T;
-
-struct dongle_ctx {
- pthread_t thr;
- unsigned char thr_finished;
- uint16_t buf[BUF_LEN];
- uint32_t buf_len;
-};
-
-struct demod_ctx {
- pthread_t thr;
- unsigned char thr_finished;
- pthread_rwlock_t lck;
- pthread_cond_t ok;
- pthread_mutex_t ok_m;
- int pre_r, pre_j, now_r, now_j, index;
- int pre_index, now_index;
- int16_t buf[BUF_LEN];
- int buf_len;
- int16_t res[BUF_LEN];
- int res_len;
-};
-
-struct output_ctx {
- pthread_t thr;
- unsigned char thr_finished;
- pthread_rwlock_t lck;
- pthread_cond_t ok;
- pthread_mutex_t ok_m;
- int16_t buf[BUF_LEN];
- int buf_len;
-};
-
-struct dev_ctx {
- int used; // radio is free ???
- rtlsdr_dev_t* dev;
- Mode mode;
- float freq;
- unsigned char mute;
- unsigned char should_run;
- /* thread contexts */
- dongle_ctx *dongle;
- demod_ctx *demod;
- output_ctx *output;
-};
-
-#define MAX_RADIO 10
-
-// Structure holding existing radio with current usage status
-typedef struct {
- int idx;
- char *name;
- int used;
-} radioDevT;
-
-// Radio plugin handle should store everething API may need
-typedef struct {
- radioDevT *radios[MAX_RADIO]; // pointer to existing radio
- int devCount;
-} pluginHandleT;
-
-/* private client context [will be destroyed when client leaves] */
-typedef struct {
- radioDevT *radio; /* pointer to client radio */
- int idx; /* radio index within global array */
- Mode mode; /* radio mode: AM/FM */
- float freq; /* radio frequency (Mhz) */
- unsigned char mute; /* radio muted: 0(false)/1(true) */
-} radioCtxHandleT;
-
-
-STATIC void* _dongle_thread_fn (void *);
-STATIC void* _demod_thread_fn (void *);
-STATIC void* _output_thread_fn (void *);
-STATIC unsigned int _radio_dev_count (void);
-STATIC const char* _radio_dev_name (unsigned int);
-STATIC unsigned char _radio_dev_init (struct dev_ctx *, unsigned int);
-STATIC unsigned char _radio_dev_free (struct dev_ctx *);
-STATIC void _radio_apply_params (struct dev_ctx *);
-STATIC void _radio_start_threads (struct dev_ctx *);
-STATIC void _radio_stop_threads (struct dev_ctx *);
-
-static unsigned int init_dev_count = 0;
-static struct dev_ctx **dev_ctx = NULL;
-
-/* ------------- RADIO IMPLEMENTATION ----------------- */
-
-
-// Radio initialization should be done only when user start the radio and not at plugin initialization
-// Making this call too early would impose to restart the binder to detect a radio.
-STATIC unsigned char _radio_on (unsigned int num, radioCtxHandleT *ctx) {
-
- if (num >= _radio_dev_count())
- return 0;
-
- if (init_dev_count < _radio_dev_count()) {
- init_dev_count = _radio_dev_count();
- dev_ctx = (dev_ctx_T**) realloc (dev_ctx, init_dev_count * sizeof(dev_ctx_T));
- }
-
- dev_ctx[num] = (dev_ctx_T*) malloc (sizeof(dev_ctx_T));
- dev_ctx[num]->dev = NULL;
- dev_ctx[num]->mode = ctx->mode;
- dev_ctx[num]->freq = ctx->freq;
- dev_ctx[num]->mute = ctx->mute;
- dev_ctx[num]->should_run = 0;
- dev_ctx[num]->dongle = NULL;
- dev_ctx[num]->demod = NULL;
- dev_ctx[num]->output = NULL;
- _radio_dev_init(dev_ctx[num], num);
-
- return 1;
-}
-
-STATIC void _radio_off (unsigned int num) {
-
- if (num >= _radio_dev_count())
- return;
-
- if (dev_ctx[num]) {
- _radio_dev_free(dev_ctx[num]);
- free(dev_ctx[num]);
- }
- /* free(dev_ctx); */
-}
-
-STATIC void _radio_set_mode (unsigned int num, Mode mode) {
- if (!dev_ctx || !dev_ctx[num])
- return;
-
- dev_ctx[num]->mode = mode;
- _radio_apply_params(dev_ctx[num]);
-}
-
-STATIC void _radio_set_freq (unsigned int num, float freq) {
- if (!dev_ctx || !dev_ctx[num])
- return;
-
- dev_ctx[num]->freq = freq;
- _radio_apply_params(dev_ctx[num]);
-}
-
-STATIC void _radio_set_mute (unsigned int num, unsigned char mute) {
- if (!dev_ctx || !dev_ctx[num])
- return;
-
- dev_ctx[num]->mute = mute;
- _radio_apply_params(dev_ctx[num]);
-}
-
-STATIC void _radio_play (unsigned int num) {
- if (!dev_ctx || !dev_ctx[num])
- return;
-
- _radio_start_threads(dev_ctx[num]);
-}
-
-STATIC void _radio_stop (unsigned int num) {
- if (!dev_ctx || !dev_ctx[num])
- return;
-
- _radio_stop_threads(dev_ctx[num]);
-}
-
- /* --- HELPER FUNCTIONS --- */
-
-STATIC unsigned int _radio_dev_count () {
- return rtlsdr_get_device_count();
-}
-
-STATIC const char* _radio_dev_name (unsigned int num) {
- return rtlsdr_get_device_name(num);
-}
-
-STATIC unsigned char _radio_dev_init (dev_ctx_T *dev_ctx, unsigned int num) {
- rtlsdr_dev_t *dev = dev_ctx->dev;
-
- if (rtlsdr_open(&dev, num) < 0)
- return 0;
-
- rtlsdr_set_tuner_gain_mode(dev, 0);
-
- if (rtlsdr_reset_buffer(dev) < 0)
- return 0;
-
- dev_ctx->dev = dev;
-
- _radio_apply_params(dev_ctx);
-
- return 1;
-}
-
-STATIC unsigned char _radio_dev_free (dev_ctx_T *dev_ctx) {
- rtlsdr_dev_t *dev = dev_ctx->dev;
-
- if (rtlsdr_close(dev) < 0)
- return 0;
- dev = NULL;
-
- dev_ctx->dev = dev;
-
- return 1;
-}
-
-STATIC void _radio_apply_params (dev_ctx_T *dev_ctx) {
- rtlsdr_dev_t *dev = dev_ctx->dev;
- Mode mode = dev_ctx->mode;
- float freq = dev_ctx->freq;
- int rate;
-
- freq *= 1000000;
- rate = ((1000000 / 200000) + 1) * 200000;
-
- if (mode == FM)
- freq += 16000;
- freq += rate / 4;
-
- rtlsdr_set_center_freq(dev, freq);
- rtlsdr_set_sample_rate(dev, rate);
-
- dev_ctx->dev = dev;
-}
-
-STATIC void _radio_start_threads (dev_ctx_T *dev_ctx) {
- rtlsdr_dev_t *dev = dev_ctx->dev;
- dev_ctx->dongle = (dongle_ctx*) malloc(sizeof(dongle_ctx));
- dev_ctx->demod = (demod_ctx*) malloc(sizeof(demod_ctx));
- dev_ctx->output = (output_ctx*) malloc(sizeof(output_ctx));
-
- dongle_ctx *dongle = dev_ctx->dongle;
- demod_ctx *demod = dev_ctx->demod;
- output_ctx *output = dev_ctx->output;
-
- pthread_rwlock_init(&demod->lck, NULL);
- pthread_cond_init(&demod->ok, NULL);
- pthread_mutex_init(&demod->ok_m, NULL);
- pthread_rwlock_init(&output->lck, NULL);
- pthread_cond_init(&output->ok, NULL);
- pthread_mutex_init(&output->ok_m, NULL);
-
- dev_ctx->should_run = 1;
-
- /* dongle thread */
- dongle->thr_finished = 0;
- pthread_create(&dongle->thr, NULL, _dongle_thread_fn, (void*)dev_ctx);
-
- /* demod thread */
- demod->pre_r = demod->pre_j = 0;
- demod->now_r = demod->now_j = 0;
- demod->index = demod->pre_index = demod->now_index = 0;
- demod->thr_finished = 0;
- pthread_create(&demod->thr, NULL, _demod_thread_fn, (void*)dev_ctx);
-
- /* output thread */
- output->thr_finished = 0;
- pthread_create(&output->thr, NULL, _output_thread_fn, (void*)dev_ctx);
-}
-
-STATIC void _radio_stop_threads (dev_ctx_T *dev_ctx) {
- rtlsdr_dev_t *dev = dev_ctx->dev;
- dongle_ctx *dongle = dev_ctx->dongle;
- demod_ctx *demod = dev_ctx->demod;
- output_ctx *output = dev_ctx->output;
-
- if (!dongle || !demod || !output)
- return;
-
- /* stop each "while" loop in threads */
- dev_ctx->should_run = 0;
-
- rtlsdr_cancel_async(dev);
- pthread_signal(&demod->ok, &demod->ok_m);
- pthread_signal(&output->ok, &output->ok_m);
-
- while (!dongle->thr_finished ||
- !demod->thr_finished ||
- !output->thr_finished)
- usleep(100000);
-
- pthread_join(dongle->thr, NULL);
- pthread_join(demod->thr, NULL);
- pthread_join(output->thr, NULL);
- pthread_rwlock_destroy(&demod->lck);
- pthread_cond_destroy(&demod->ok);
- pthread_mutex_destroy(&demod->ok_m);
- pthread_rwlock_destroy(&output->lck);
- pthread_cond_destroy(&output->ok);
- pthread_mutex_destroy(&output->ok_m);
-
- free(dongle); dev_ctx->dongle = NULL;
- free(demod); dev_ctx->demod = NULL;
- free(output); dev_ctx->output = NULL;
-}
-
- /* ---- LOCAL THREADED FUNCTIONS ---- */
-
-STATIC void _rtlsdr_callback (unsigned char *buf, uint32_t len, void *ctx) {
- dev_ctx_T *dev_ctx = (dev_ctx_T *)ctx;
- dongle_ctx *dongle = dev_ctx->dongle;
- demod_ctx *demod = dev_ctx->demod;
- unsigned char tmp;
- int i;
-
- if (!dev_ctx->should_run)
- return;
-
- /* rotate 90° */
- for (i = 0; i < (int)len; i += 8) {
- 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;
- }
-
- /* write data */
- for (i = 0; i < (int)len; i++)
- dongle->buf[i] = (int16_t)buf[i] - 127;
-
- /* lock demod thread, write to it, unlock */
- pthread_rwlock_wrlock(&demod->lck);
- memcpy(demod->buf, dongle->buf, 2 * len);
- demod->buf_len = len;
- pthread_rwlock_unlock(&demod->lck);
- pthread_signal(&demod->ok, &demod->ok_m);
-}
- /**/
-STATIC void* _dongle_thread_fn (void *ctx) {
- dev_ctx_T *dev_ctx = (dev_ctx_T *)ctx;
- dongle_ctx *dongle = dev_ctx->dongle;
-
- rtlsdr_read_async(dev_ctx->dev, _rtlsdr_callback, dev_ctx, 0, 0);
-
- dongle->thr_finished = 1;
- return 0;
-}
-
-STATIC void _lowpass_demod (void *ctx) {
- demod_ctx *demod = (demod_ctx *)ctx;
- int i=0, i2=0;
-
- while (i < demod->buf_len) {
- demod->now_r += demod->buf[i];
- demod->now_j += demod->buf[i+1];
- i += 2;
- demod->index++;
- if (demod->index < ((1000000 / 200000) + 1))
- continue;
- demod->buf[i2] = demod->now_r;
- demod->buf[i2+1] = demod->now_j;
- demod->index = 0;
- demod->now_r = demod->now_j = 0;
- i2 += 2;
- }
- demod->buf_len = i2;
-}
- /**/
-STATIC void _lowpassreal_demod (void *ctx) {
- demod_ctx *demod = (demod_ctx *)ctx;
- int i=0, i2=0;
- int fast = 200000;
- int slow = 48000;
-
- while (i < demod->res_len) {
- demod->now_index += demod->res[i];
- i++;
- demod->pre_index += slow;
- if (demod->pre_index < fast)
- continue;
- demod->res[i2] = (int16_t)(demod->now_index / (fast/slow));
- demod->pre_index -= fast;
- demod->now_index = 0;
- i2 += 1;
- }
- demod->res_len = i2;
-}
- /**/
-STATIC void _multiply (int ar, int aj, int br, int bj, int *cr, int *cj) {
- *cr = ar*br - aj*bj;
- *cj = aj*br + ar*bj;
-}
- /**/
-STATIC 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));
-}
- /**/
-STATIC void _fm_demod (void *ctx) {
- demod_ctx *demod = (demod_ctx *)ctx;
- int16_t *buf = demod->buf;
- int buf_len = demod->buf_len;
- int pcm, i;
-
- pcm = _polar_discriminant(buf[0], buf[1], demod->pre_r, demod->pre_j);
- demod->res[0] = (int16_t)pcm;
-
- for (i = 2; i < (buf_len-1); i += 2) {
- pcm = _polar_discriminant(buf[i], buf[i+1], buf[i-2], buf[i-1]);
- demod->res[i/2] = (int16_t)pcm;
- }
- demod->pre_r = buf[buf_len - 2];
- demod->pre_j = buf[buf_len - 1];
- demod->res_len = buf_len/2;
-}
- /**/
-STATIC void _am_demod (void *ctx) {
- demod_ctx *demod = (demod_ctx *)ctx;
- int16_t *buf = demod->buf;
- int buf_len = demod->buf_len;
- int pcm, i;
-
- for (i = 0; i < buf_len; i += 2) {
- pcm = buf[i] * buf[i];
- pcm += buf[i+1] * buf[i+1];
- demod->res[i/2] = (int16_t)sqrt(pcm);
- }
- demod->res_len = buf_len/2;
-}
- /**/
-STATIC void* _demod_thread_fn (void *ctx) {
- dev_ctx_T *dev_ctx = (dev_ctx_T *)ctx;
- demod_ctx *demod = dev_ctx->demod;
- output_ctx *output = dev_ctx->output;
-
- while(dev_ctx->should_run) {
- pthread_wait(&demod->ok, &demod->ok_m);
- pthread_rwlock_wrlock(&demod->lck);
- _lowpass_demod(demod);
- if (dev_ctx->mode == FM)
- _fm_demod(demod);
- else
- _am_demod(demod);
- _lowpassreal_demod(demod);
- pthread_rwlock_unlock(&demod->lck);
-
- /* lock demod thread, write to it, unlock */
- pthread_rwlock_wrlock(&output->lck);
- memcpy(output->buf, demod->res, 2 * demod->res_len);
- output->buf_len = demod->res_len;
- pthread_rwlock_unlock(&output->lck);
- pthread_signal(&output->ok, &output->ok_m);
- }
-
- demod->thr_finished = 1;
- return 0;
-}
-
-STATIC void* _output_thread_fn (void *ctx) {
- dev_ctx_T *dev_ctx = (dev_ctx_T *)ctx;
- output_ctx *output = dev_ctx->output;
-
- while (dev_ctx->should_run) {
- pthread_wait(&output->ok, &output->ok_m);
- pthread_rwlock_rdlock(&output->lck);
- //if (!dev_ctx->mute)
- // mRadio->PlayAlsa((void*)&output->buf, output->buf_len);
- pthread_rwlock_unlock(&output->lck);
- }
-
- output->thr_finished = 1;
- return 0;
-}
-