+ event_t e;
+ e.type = NEW_BUTTON_PRESS;
+ e.buttonpress.timestamp = now;
+ queue_try_add_ignoring_errors(&queue, &e);
+ }
+}
+
+static void time_to_send(uint _) {
+ /* This runs in interrupt context; don't linger. */
+ event_t e;
+ e.type = RESEND_TIME;
+ queue_try_add_ignoring_errors(&queue, &e);
+}
+
+void set_send_alarm(int alarm, uint32_t now, uint32_t next_act_time) {
+ uint32_t sleep_duration = next_act_time - now;
+ if (hardware_alarm_set_target(alarm,
+ make_timeout_time_ms(sleep_duration * 1000)))
+ signal_error_by_blinking();
+ return;
+}
+
+void service_sleeps(int alarm, send_t *sleeping_sends, pheap_t *sleeps_heap) {
+ hardware_alarm_cancel(alarm);
+
+ while (1) {
+ uint32_t now = time_s();
+ int32_t act_time = next_scheduled_send(sleeping_sends, sleeps_heap);
+ if (act_time == -1)
+ return;
+ if (act_time > now) {
+ set_send_alarm(alarm, now, act_time);
+ return;
+ }
+ pheap_node_id_t i = ph_remove_head(sleeps_heap, false);
+ send_t *send = &sleeping_sends[i];
+ uint32_t ago = now - send->timestamp;
+ send_report_packet(send->seq, ago);
+ send->send_count++;
+ if (send->send_count < config_resend_count)
+ ph_insert_node(sleeps_heap, i);
+ else
+ ph_free_node(sleeps_heap, i);
+ }
+}
+
+void service_queue() {
+ int alarm = hardware_alarm_claim_unused(true);
+ if (alarm == -1)
+ signal_error_by_blinking();
+ hardware_alarm_set_callback(alarm, time_to_send);
+
+ send_t sleeping_sends[PICO_PHEAP_MAX_ENTRIES];
+ pheap_t *sleeps_heap =
+ ph_create(PICO_PHEAP_MAX_ENTRIES, next_send_less_than, sleeping_sends);
+ u16_t seq = 0;
+ while (1) {
+ service_sleeps(alarm, sleeping_sends, sleeps_heap);
+
+ event_t e;
+ queue_remove_blocking(&queue, &e);
+ switch (e.type) {
+ case NEW_BUTTON_PRESS: {
+ create_send(sleeping_sends, sleeps_heap, e.buttonpress.timestamp, seq++);
+ } break;
+ case RESEND_TIME: {
+ /* OK, we're awake. Cool. Thanks! (We actually do the sends in the
+ * service_sleeps() call at the top of the loop.) */
+ } break;
+ default:
+ signal_error_by_blinking();
+ }