Implement persistent alarm storage

components/alarms/CMakeLists.txt

@@ -1,5 +1,5 @@
 idf_component_register(
-  SRCS "alarms.c"
+  SRCS "alarm_store.c" "alarms.c"
   INCLUDE_DIRS "."
-  REQUIRES console_wrapper sound time
+  REQUIRES console_wrapper esp_partition fatal sound system_utils time
 )

components/alarms/alarm_store.c

@@ -0,0 +1,77 @@
+/*
+ * SPDX-License-Identifier: AGPL-3.0-only
+ * Copyright (c) Camden Dixie O'Brien
+ */
+
+#include "alarm_store.h"
+
+#include "fatal.h"
+
+#include "esp_log.h"
+#include "esp_partition.h"
+#include "system_utils.h"
+#include <string.h>
+
+#define TAG "Alarm store"
+
+Alarm alarms[CONFIG_MAX_ALARMS];
+
+static const esp_partition_t *partition;
+
+static unsigned erase_size(void)
+{
+	unsigned sector_count = sizeof(alarms) / partition->erase_size;
+	if (sizeof(alarms) % partition->erase_size != 0)
+		++sector_count;
+	return partition->erase_size * sector_count;
+}
+
+static void load()
+{
+	const esp_err_t error
+	    = esp_partition_read(partition, 0, alarms, sizeof(alarms));
+	if (error != ESP_OK) {
+		ESP_LOGE(TAG, "Error reading from alarms partition: %02x", error);
+		FATAL();
+	}
+	unsigned count = 0;
+	for (unsigned i = 0; i < CONFIG_MAX_ALARMS; ++i) {
+		if (alarms[i].set)
+			++count;
+	}
+	ESP_LOGI(TAG, "Loaded %u alarms from storage", count);
+}
+
+void alarm_store_init()
+{
+	partition = esp_partition_find_first(
+	    ESP_PARTITION_TYPE_DATA, ESP_PARTITION_SUBTYPE_DATA_UNDEFINED,
+	    "alarms");
+	if (partition == NULL) {
+		ESP_LOGE(TAG, "Unable to find alarms partition");
+		FATAL();
+	}
+
+	if (is_first_boot()) {
+		ESP_LOGI(TAG, "Zeroing alarm store");
+		memset(alarms, 0, sizeof(alarms));
+		alarm_store_save();
+	} else {
+		load();
+	}
+}
+
+void alarm_store_save()
+{
+	esp_err_t error;
+
+	error = esp_partition_erase_range(partition, 0, erase_size());
+	if (error != ESP_OK) {
+		ESP_LOGE(TAG, "Error erasing alarm storage: %02x", error);
+		return;
+	}
+
+	error = esp_partition_write(partition, 0, alarms, sizeof(alarms));
+	if (error != ESP_OK)
+		ESP_LOGE(TAG, "Error writing alarm storage: %02x", error);
+}

components/alarms/alarm_store.h

@@ -0,0 +1,31 @@
+/*
+ * SPDX-License-Identifier: AGPL-3.0-only
+ * Copyright (c) Camden Dixie O'Brien
+ */
+
+#ifndef ALARM_STORE_H
+#define ALARM_STORE_H
+
+#include "time_manager.h"
+
+#include "sdkconfig.h"
+#include <stdbool.h>
+
+typedef struct {
+	bool set;
+	Time time;
+} Alarm;
+
+extern Alarm alarms[CONFIG_MAX_ALARMS];
+
+/**
+ * Initialize alarm store and load alarms from storage.
+ */
+void alarm_store_init(void);
+
+/**
+ * Save alarms to storage.
+ */
+void alarm_store_save(void);
+
+#endif

components/alarms/alarms.c

@@ -5,9 +5,9 @@
 
 #include "alarms.h"
 
+#include "alarm_store.h"
 #include "console.h"
 #include "sound.h"
-#include "time_manager.h"
 
 #include "esp_log.h"
 #include "freertos/FreeRTOS.h"
@@ -18,17 +18,11 @@
 
 #define TAG "Alarms"
 
-typedef struct {
-	bool set;
-	Time time;
-} Alarm;
-
 typedef struct {
 	const Alarm *alarm;
 	Time end;
 } ActiveAlarm;
 
-static Alarm alarms[CONFIG_MAX_ALARMS];
 static ActiveAlarm active[CONFIG_MAX_ALARMS];
 static unsigned active_count;
 static ActiveAlarm snoozed[CONFIG_MAX_ALARMS];
@@ -53,6 +47,7 @@ static bool add_alarm(Time time)
 		if (!alarms[i].set) {
 			alarms[i].set = true;
 			alarms[i].time = time;
+			alarm_store_save();
 			return true;
 		}
 	}
@@ -62,6 +57,7 @@ static bool add_alarm(Time time)
 static void remove_alarm(unsigned index)
 {
 	alarms[index].set = false;
+	alarm_store_save();
 }
 
 static void activate(const Alarm *alarm)
@@ -212,13 +208,14 @@ static int command_func(int argc, char **argv)
 
 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();
 
+	alarm_store_init();
+
 	add_time_callback(check_alarms);
 
 	console_register(

partitions.csv

@@ -0,0 +1,6 @@
+# ESP-IDF Partition Table
+# Name, Type, SubType, Offset, Size, Flags
+nvs,data,nvs,0x9000,24K,
+phy_init,data,phy,0xf000,4K,
+factory,app,factory,0x10000,1M,
+alarms,data,undefined,,8K

sdkconfig.defaults

@@ -1,4 +1,5 @@
 # This file was generated using idf.py save-defconfig. It can be edited manually.
 # Espressif IoT Development Framework (ESP-IDF) Project Minimal Configuration
 #
+CONFIG_PARTITION_TABLE_CUSTOM=y
 CONFIG_FREERTOS_UNICORE=y