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 int main() {
  55   stdio_init_all();
  56   if (cyw43_arch_init_with_country(CYW43_COUNTRY_USA))
  57     signal_error_by_blinking();
  58   cyw43_arch_enable_sta_mode();
  59   signal(3, 100);
  60   if (cyw43_arch_wifi_connect_timeout_ms(config_wifi_ssid, config_wifi_pass,
  61                                          CYW43_AUTH_WPA2_AES_PSK, 90000))
  62     signal_error_by_blinking();
  63   signal(2, 300);
  64
  65   queue_init(&queue, sizeof(event_t), 99);
  66
  67   begin_listening_for_button_press(button_pressed);
  68
  69   u16_t seq = 0;
  70   while (1) {
  71     event_t e;
  72     queue_remove_blocking(&queue, &e);
  73     switch (e.type) {
  74     case BUTTONPRESS: {
  75       event_t send_e;
  76       send_e.type = SEND;
  77       send_e.send.timestamp = e.buttonpress.timestamp;
  78       send_e.send.seq = seq++;
  79       send_e.send.send_count = 0;
  80       queue_try_add_ignoring_errors(&queue, &send_e);
  81     } break;
  82     case SEND: {
  83       uint32_t now = time_s();
  84       uint32_t ago = now - e.send.timestamp;
  85       send_report(e.send.seq, ago);
  86       e.send.send_count++;
  87       if (e.send.send_count < config_resend_count)
  88         queue_try_add_ignoring_errors(&queue, &e);
  89       /* TODO: Sleep elsewhere. */
  90       signal(e.send.send_count == 1 ? 2 : 1, 100);
  91       sleep_ms(config_resend_interval_ms);
  92     } break;
  93     default:
  94       signal_error_by_blinking();
  95     }
  96   }
  97 }