Add support for snoozing alarms

Also modified time_manager to pass time by value to time callbacks as
it's a fairly small struct and it will probably be more robust.

components/alarms/alarms.c

@@ -10,6 +10,8 @@
 #include "time_manager.h"
 
 #include "esp_log.h"
+#include "freertos/FreeRTOS.h"
+#include "freertos/semphr.h"
 #include <stdbool.h>
 #include <stdio.h>
 #include <string.h>
@@ -29,7 +31,21 @@ typedef struct {
 static Alarm alarms[CONFIG_MAX_ALARMS];
 static ActiveAlarm active[CONFIG_MAX_ALARMS];
 static unsigned active_count;
+static ActiveAlarm snoozed[CONFIG_MAX_ALARMS];
+static unsigned snoozed_count;
 static Time last_check;
+static SemaphoreHandle_t state_mutex;
+
+static Time in_minutes(unsigned minutes)
+{
+	Time time = get_time();
+	time.minute += minutes;
+	if (time.minute >= 60) {
+		time.minute %= 60;
+		++time.hour;
+	}
+	return time;
+}
 
 static bool add_alarm(Time time)
 {
@@ -48,68 +64,107 @@ static void remove_alarm(unsigned index)
 	alarms[index].set = false;
 }
 
-static void activate(unsigned index, Time end)
+static void activate(const Alarm *alarm)
 {
+	if (alarm < &alarms[0] || alarm >= &alarms[CONFIG_MAX_ALARMS]
+	    || !alarm->set) {
+		ESP_LOGE(TAG, "Invalid alarm passed to %s()", __func__);
+		return;
+	}
+
 	if (active_count == 0)
 		sound_alert_on();
 
-	active[active_count].alarm = &alarms[index];
+	active[active_count].alarm = alarm;
-	active[active_count].end = end;
+	active[active_count].end = in_minutes(CONFIG_ALERT_MINUTES);
 	++active_count;
-
-	ESP_LOGI(TAG, "Alarm %u activated", index);
 }
 
 static void dismiss(unsigned index)
 {
+	if (index >= active_count) {
+		ESP_LOGE(
+		    TAG, "Invalid active index %u passed to %s()", index, __func__);
+		return;
+	}
+
 	if (active_count == 1)
 		sound_alert_off();
 
 	for (unsigned i = index + 1; i < active_count; ++i)
 		active[i - 1] = active[i];
 	--active_count;
-
-	ESP_LOGI(TAG, "Alarm %u dismissed", index);
 }
 
-static bool passed_since_last_check(Time time, const Time *now)
+static void snooze(unsigned index)
 {
-	return last_check.hour <= time.hour && time.hour <= now->hour
+	if (index >= active_count) {
-	    && last_check.minute <= time.minute && time.minute <= now->minute
+		ESP_LOGE(
-	    && last_check.second <= time.second && time.second <= now->second;
+		    TAG, "Invalid active index %u passed to %s()", index, __func__);
-}
+		return;
-
-static Time add_minutes(const Time *time, unsigned minutes)
-{
-	Time new_time = {
-		.hour = time->hour,
-		.minute = time->minute + minutes,
-		.second = time->second,
-	};
-
-	if (new_time.minute >= 60) {
-		new_time.minute %= 60;
-		++new_time.hour;
 	}
 
-	return new_time;
+	const Alarm *alarm = active[index].alarm;
+	dismiss(index);
+
+	snoozed[snoozed_count].alarm = alarm;
+	snoozed[snoozed_count].end = in_minutes(CONFIG_SNOOZE_MINUTES);
+	++snoozed_count;
+
+	ESP_LOGI(TAG, "Alarm %u snoozed", alarm - &alarms[0]);
 }
 
-static void check_alarms(const Time *now)
+static void unsnooze(unsigned index)
 {
+	if (index >= snoozed_count) {
+		ESP_LOGE(
+		    TAG, "Invalid snooze index %u passed to %s()", index, __func__);
+		return;
+	}
+
+	activate(snoozed[index].alarm);
+
+	for (unsigned i = index + 1; i < snoozed_count; ++i)
+		snoozed[i - 1] = snoozed[i];
+	--snoozed_count;
+}
+
+static bool passed_since_last_check(Time time, Time now)
+{
+	return last_check.hour <= time.hour && time.hour <= now.hour
+	    && last_check.minute <= time.minute && time.minute <= now.minute
+	    && last_check.second <= time.second && time.second <= now.second;
+}
+
+static void check_alarms(Time now)
+{
+	// Skip if time hasn't changed since last check
+	if (last_check.hour == now.hour && last_check.minute == now.minute
+	    && last_check.second == now.second)
+		return;
+
+	if (xSemaphoreTake(state_mutex, (TickType_t)10) == pdFALSE)
+		return;
+
 	for (unsigned i = 0; i < CONFIG_MAX_ALARMS; ++i) {
 		if (!alarms[i].set)
 			continue;
 		if (passed_since_last_check(alarms[i].time, now))
-			activate(i, add_minutes(now, CONFIG_ALERT_MINUTES));
+			activate(&alarms[i]);
 	}
 
-	for (unsigned i = 0; i != active_count; ++i) {
+	for (unsigned i = 0; i < active_count; ++i) {
 		if (passed_since_last_check(active[i].end, now))
 			dismiss(i);
 	}
 
-	last_check = *now;
+	for (unsigned i = 0; i < snoozed_count; ++i) {
+		if (passed_since_last_check(snoozed[i].end, now))
+			unsnooze(i);
+	}
+
+	last_check = now;
+	xSemaphoreGive(state_mutex);
 }
 
 static int command_func(int argc, char **argv)
@@ -160,6 +215,8 @@ void alarms_init(void)
 	memset(alarms, 0, sizeof(alarms));
 	memset(active, 0, sizeof(active));
 	active_count = 0;
+	memset(snoozed, 0, sizeof(snoozed));
+	snoozed_count = 0;
 	last_check = get_time();
 
 	add_time_callback(check_alarms);
@@ -168,14 +225,32 @@ void alarms_init(void)
 	    "alarms", "List, add and remove alarms",
 	    "alarms OR alarms add <hh:mm> OR alarms remove <index>",
 	    command_func);
+
+	state_mutex = xSemaphoreCreateMutex();
 }
 
 void alarm_snooze(void)
 {
+	if (xSemaphoreTake(state_mutex, (TickType_t)10) == pdFALSE) {
+		ESP_LOGE(TAG, "Unable to aquire state semaphore");
+		return;
+	}
+
+	if (active_count > 0)
+		snooze(0);
+
+	xSemaphoreGive(state_mutex);
 }
 
 void alarm_dismiss(void)
 {
+	if (xSemaphoreTake(state_mutex, (TickType_t)10) == pdFALSE) {
+		ESP_LOGE(TAG, "Unable to aquire state semaphore");
+		return;
+	}
+
 	if (active_count > 0)
 		dismiss(0);
+
+	xSemaphoreGive(state_mutex);
 }

components/display/display.c

@@ -51,9 +51,9 @@ static void show_time(unsigned hour, unsigned minute)
 	show_digit(DISPLAY_DIGIT_4, minute % 10);
 }
 
-static void update_time(const Time *time)
+static void update_time(Time now)
 {
-	show_time(time->hour, time->minute);
+	show_time(now.hour, now.minute);
 }
 
 void display_init()

components/time/time_manager.c

@@ -38,7 +38,7 @@ static void run_callbacks(void *arg)
 {
 	const Time time = get_time();
 	for (unsigned i = 0; i < callback_count; ++i)
-		callbacks[i](&time);
+		callbacks[i](time);
 }
 
 static int time_command_func(int argc, char **argv)

components/time/time_manager.h

@@ -28,7 +28,7 @@ typedef enum {
 	WEEK_DAY_SUNDAY,
 } WeekDay;
 
-typedef void (*TimeCallback)(const Time *time);
+typedef void (*TimeCallback)(Time now);
 
 /**
  * Initialize the time module.