git.scottworley.com Git - tattlekey/blob - client/tattlekey.c

   1 #include "pico/cyw43_arch.h"
   2 #include "pico/stdlib.h"
   3 #include "pico/util/queue.h"
   4
   5 #include "blink.h"
   6 #include "button.h"
   7 #include "config.h"
   8 #include "net.h"
   9
  10 enum event_type { BUTTONPRESS, SEND };
  11 typedef struct {
  12   enum event_type type;
  13   union {
  14     struct {
  15       uint32_t timestamp;
  16     } buttonpress;
  17     struct {
  18       uint32_t timestamp;
  19       u16_t seq;
  20       u8_t send_count;
  21     } send;
  22   };
  23 } event_t;
  24
  25 queue_t queue;
  26
  27 uint32_t time_s() { return time_us_64() / 1000000ul; }
  28
  29 /* Often we don't bother checking for failure (full queue) because
  30  *   1. The best thing to do in this unfortunate situation is to blithely
  31  *      continue, dropping some events; continuing is better than stopping.
  32  *   2. Neither interrupt context nor queue-processing context can block
  33  *      until space is available, or even sit around & blink the LED to
  34  *      signal a problem.
  35  * (We also get a bit of type safety by taking event_t* rather than void*.) */
  36 static void queue_try_add_ignoring_errors(queue_t *q, event_t *e) {
  37   queue_try_add(q, e);
  38 }
  39
  40 static void button_pressed() {
  41   /* This runs in interrupt context; don't linger.  */
  42   static uint64_t last_button_press_time = 0;
  43   uint32_t now = time_s();
  44   uint32_t time_since_last_press = now - last_button_press_time;
  45   if (time_since_last_press >= config_minimum_seconds_between_button_presses) {
  46     last_button_press_time = now;
  47     event_t e;
  48     e.type = BUTTONPRESS;
  49     e.buttonpress.timestamp = now;
  50     queue_try_add_ignoring_errors(&queue, &e);
  51   }
  52 }
  53
  54 void service_queue() {
  55   u16_t seq = 0;
  56   while (1) {
  57     event_t e;
  58     queue_remove_blocking(&queue, &e);
  59     switch (e.type) {
  60     case BUTTONPRESS: {
  61       event_t send_e;
  62       send_e.type = SEND;
  63       send_e.send.timestamp = e.buttonpress.timestamp;
  64       send_e.send.seq = seq++;
  65       send_e.send.send_count = 0;
  66       queue_try_add_ignoring_errors(&queue, &send_e);
  67     } break;
  68     case SEND: {
  69       uint32_t now = time_s();
  70       uint32_t ago = now - e.send.timestamp;
  71       send_report(e.send.seq, ago);
  72       e.send.send_count++;
  73       if (e.send.send_count < config_resend_count)
  74         queue_try_add_ignoring_errors(&queue, &e);
  75       /* TODO: Sleep elsewhere. */
  76       signal(e.send.send_count == 1 ? 2 : 1, 100);
  77       sleep_ms(config_resend_interval_ms);
  78     } break;
  79     default:
  80       signal_error_by_blinking();
  81     }
  82   }
  83 }
  84
  85 int main() {
  86   stdio_init_all();
  87   if (cyw43_arch_init_with_country(CYW43_COUNTRY_USA))
  88     signal_error_by_blinking();
  89   cyw43_arch_enable_sta_mode();
  90   signal(3, 100);
  91   if (cyw43_arch_wifi_connect_timeout_ms(config_wifi_ssid, config_wifi_pass,
  92                                          CYW43_AUTH_WPA2_AES_PSK, 90000))
  93     signal_error_by_blinking();
  94   signal(2, 300);
  95
  96   queue_init(&queue, sizeof(event_t), 99);
  97
  98   begin_listening_for_button_press(button_pressed);
  99
 100   service_queue();
 101 }