+/* tattlekey: A one-key UDP keyboard
+ * Copyright (C) 2023 Scott Worley <scottworley@scottworley.com>
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program. If not, see <https://www.gnu.org/licenses/>.
+ */
+
#include "pico/cyw43_arch.h"
#include "pico/stdlib.h"
+#include "pico/util/pheap.h"
#include "pico/util/queue.h"
#include "blink.h"
#include "button.h"
#include "config.h"
#include "net.h"
+#include "press.h"
-enum event_type { BUTTONPRESS };
+enum event_type { NEW_BUTTON_PRESS, RESEND_TIME };
typedef struct {
enum event_type type;
union {
uint32_t time_s() { return time_us_64() / 1000000ul; }
+/* Often we don't bother checking for failure (full queue) because
+ * 1. The best thing to do in this unfortunate situation is to blithely
+ * continue, dropping some events; continuing is better than stopping.
+ * 2. Neither interrupt context nor queue-processing context can block
+ * until space is available, or even sit around & blink the LED to
+ * signal a problem.
+ * (We also get a bit of type safety by taking event_t* rather than void*.) */
+static void queue_try_add_ignoring_errors(queue_t *q, event_t *e) {
+ queue_try_add(q, e);
+}
+
static void button_pressed() {
/* This runs in interrupt context; don't linger. */
static uint64_t last_button_press_time = 0;
if (time_since_last_press >= config_minimum_seconds_between_button_presses) {
last_button_press_time = now;
event_t e;
- e.type = BUTTONPRESS;
+ e.type = NEW_BUTTON_PRESS;
e.buttonpress.timestamp = now;
- /* We don't check for failure (full queue) here because there's not much to
- * be done about it. */
- queue_try_add(&queue, &e);
+ 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_resend_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();
+}
+
+void service_sleeps(int alarm, press_pile_t *pp) {
+ hardware_alarm_cancel(alarm);
+
+ while (1) {
+ uint32_t now = time_s();
+ int32_t act_time = next_scheduled_send(pp);
+ if (act_time == -1)
+ return;
+ if (act_time > now) {
+ set_resend_alarm(alarm, now, act_time);
+ return;
+ }
+ press_t press;
+ if (!get_press_due_for_resend(pp, now, &press))
+ signal_error_by_blinking();
+ uint32_t ago = now - press.timestamp;
+ send_report_packet(press.seq, ago);
+ press.send_count++;
+ if (press.send_count < config_resend_count) {
+ add_press(pp, &press);
+ }
+ }
+}
+
+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);
+
+ press_pile_t *pp = create_press_pile();
+ u16_t seq = 0;
+ while (1) {
+ service_sleeps(alarm, pp);
+
+ event_t e;
+ queue_remove_blocking(&queue, &e);
+ switch (e.type) {
+ case NEW_BUTTON_PRESS: {
+ add_press(pp, &(press_t){e.buttonpress.timestamp, seq++, 0});
+ } 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();
+ }
}
}
begin_listening_for_button_press(button_pressed);
- u16_t seq = 0;
- while (1) {
- event_t e;
- queue_remove_blocking(&queue, &e);
- switch (e.type) {
- case BUTTONPRESS:
- seq++;
- for (int i = 0; i < config_resend_count; i++) {
- uint32_t now = time_s();
- uint32_t ago = now - e.buttonpress.timestamp;
- send_report(seq, ago);
- signal(i == 0 ? 2 : 1, 100);
- sleep_ms(config_resend_interval_ms);
- }
- break;
- default:
- signal_error_by_blinking();
- }
- }
+ service_queue();
}