client: Calculate 'ago' with a clock

[tattlekey] / client / tattlekey.c

#include "pico/cyw43_arch.h"
#include "pico/stdlib.h"
#include "pico/util/queue.h"

#include "blink.h"
#include "button.h"
#include "config.h"
#include "net.h"

queue_t queue;

uint32_t time_s() { return time_us_64() / 1000000ul; }

static void button_pressed() {
  /* This runs in interrupt context; don't linger.  */
  static uint64_t last_button_press_time = 0;
  uint32_t now = time_s();
  uint32_t time_since_last_press = now - last_button_press_time;
  if (time_since_last_press >= minimum_seconds_between_button_presses) {
    last_button_press_time = now;
    /* We don't check for failure (full queue) here because there's not much to
     * be done about it. */
    queue_try_add(&queue, &now);
  }
}

int main() {
  stdio_init_all();
  if (cyw43_arch_init_with_country(CYW43_COUNTRY_USA))
    signal_error_by_blinking();
  cyw43_arch_enable_sta_mode();
  signal(3, 100);
  if (cyw43_arch_wifi_connect_timeout_ms(wifi_ssid, wifi_pass,
                                         CYW43_AUTH_WPA2_AES_PSK, 90000))
    signal_error_by_blinking();
  signal(2, 300);

  queue_init(&queue, sizeof(uint32_t), 99);

  begin_listening_for_button_press(button_pressed);

  u16_t seq = 0;
  while (1) {
    uint32_t t;
    queue_remove_blocking(&queue, &t);
    seq++;
    for (int i = 0; i < resend_count; i++) {
      uint32_t now = time_s();
      uint32_t ago = now - t;
      send_report(seq, ago);
      signal(i == 0 ? 2 : 1, 100);
      sleep_ms(resend_interval_ms);
    }
  }
}