(iot/goam/wifi) Reworked, significantly more robust connection "algorithm"

- Connecting is done with two tasks, one taking up close to no resources, while the second does the connecting
- Added a more robust mechanism for reconnecting and retrying
- Fixed crashing related to task-init of ptc06

2 files changed, 67 insertions, 16 deletions

diff --git a/Year 3/Internet of things/goam/main/wifi.c b/Year 3/Internet of things/goam/main/wifi.c
index 09b62ea..fc7b141 100644
--- a/Year 3/Internet of things/goam/main/wifi.c
+++ b/Year 3/Internet of things/goam/main/wifi.c
@@ -24,7 +24,8 @@ static const char *TAG = "wifi_station";
 static void netif_init() {
 	ESP_ERROR_CHECK(esp_netif_init());
 
-	esp_netif_create_default_wifi_sta();
+	esp_netif_t *sta_netif = esp_netif_create_default_wifi_sta();
+	assert(sta_netif);
 	ESP_LOGI(TAG, "NETIF initialized");
 }
 
@@ -33,8 +34,6 @@ static void netif_init() {
  */
 
 static void wifi_connect_station(const char* ssid, wifi_auth_mode_t auth, const char* pass) {
-	ESP_ERROR_CHECK(esp_wifi_set_mode(WIFI_MODE_STA));
-
 	wifi_config_t wifi_config = {
 		.sta.threshold.authmode = auth
 	};
@@ -45,27 +44,74 @@ static void wifi_connect_station(const char* ssid, wifi_auth_mode_t auth, const
 	}
 
 	ESP_ERROR_CHECK(esp_wifi_set_config(WIFI_IF_STA, &wifi_config));
-	esp_wifi_connect();
+	ESP_ERROR_CHECK_WITHOUT_ABORT(esp_wifi_connect());
 }
 
 static unsigned short MAX_AP = 16;
 
-static bool connect_to_open() {
+#define TO_CONNECT_BIT 0b01
+#define CONNECTED_BIT  0b10
+
+static TaskHandle_t launcher_handle = NULL;
+
+static void scan_and_connect_task() {
+	display_printon("---.---.---.---", 2);
 	ESP_ERROR_CHECK(esp_wifi_scan_start(NULL, true));
 
 	wifi_ap_record_t ap_info[MAX_AP];
 	unsigned short ap_count = 0;
 	ESP_ERROR_CHECK(esp_wifi_scan_get_ap_num(&ap_count));
+	if (ap_count > MAX_AP) {
+		ap_count = MAX_AP;
+	}
 	ESP_ERROR_CHECK(esp_wifi_scan_get_ap_records(&MAX_AP, ap_info));
 
+	ESP_LOGI(TAG, "Found %d WiFi networks", ap_count);
+
+	int stored_ind = -2;
 	for (int i = 0; i < ap_count; i++) {
 		ESP_LOGD(TAG, "Found network \"%s\"", (const char*)ap_info[i].ssid);
-		if (ap_info[i].authmode == WIFI_AUTH_OPEN) {
+
+		if (strcmp((const char*)ap_info[i].ssid, ESP_WIFI_SSID) == 0) {
+			stored_ind = i;
+		}
+
+		if (ap_info[i].authmode == WIFI_AUTH_OPEN && ap_info[i].rssi >= -70) {
+			ESP_LOGI(TAG, "Connecting to \"%s\"", (const char*)ap_info[i].ssid);
 			wifi_connect_station((const char*)ap_info[i].ssid, WIFI_AUTH_OPEN, NULL);
-			return true;
+			stored_ind = -2;
+			break;
 		}
 	}
-	return false;
+
+	if (stored_ind > -1) {
+		ESP_LOGI(TAG, "Couldn't find a good open network, connecting to configured net");
+		wifi_connect_station(ESP_WIFI_SSID, ESP_WIFI_SCAN_AUTH_MODE_THRESHOLD, ESP_WIFI_PASS);
+	}
+
+	xTaskNotify(launcher_handle, CONNECTED_BIT, eSetBits);
+	if (stored_ind == -2) {
+		ESP_LOGW(TAG, "Couldn't find a good open network or the configured net, will retry in 2 seconds");
+		vTaskDelay(2000 / portTICK_PERIOD_MS);
+		xTaskNotify(launcher_handle, TO_CONNECT_BIT, eSetBits);
+	}
+
+	vTaskDelete(NULL);
+}
+
+static void launcher_scan_and_connect_task(void*) {
+	long unsigned int notification = 0;
+	while (true) {
+		do {
+			xTaskNotifyWait(ULONG_MAX, 0, &notification, 100 / portTICK_PERIOD_MS);
+		} while (!(notification & TO_CONNECT_BIT));
+
+		xTaskCreate(scan_and_connect_task, "scan_and_connect_task", 4096, NULL, 10, NULL);
+
+		do {
+			xTaskNotifyWait(ULONG_MAX, 0, &notification, 100 / portTICK_PERIOD_MS);
+		} while (!(notification & CONNECTED_BIT));
+	}
 }
 
 /*
@@ -79,10 +125,11 @@ static void sta_disconnect_handler(void* arg, esp_event_base_t event_base, int32
 		esp_wifi_connect();
 		connect_tries++;
 		ESP_LOGW(TAG, "Retrying to connect... Try %d/%d", connect_tries, ESP_MAXIMUM_RETRY);
+		vTaskDelay(100 / portTICK_PERIOD_MS);
 	}
 	else {
-		ESP_LOGW(TAG, "Failed to connect to SSID:%s, password:%s, will now try to connect to open...", ESP_WIFI_SSID, ESP_WIFI_PASS);
-		connect_to_open();
+		ESP_LOGW(TAG, "Failed to connect to SSID:%s, password:%s, rescanning connections", ESP_WIFI_SSID, ESP_WIFI_PASS);
+		xTaskNotify(launcher_handle, TO_CONNECT_BIT, eSetBits);
 	}
 }
 
@@ -112,16 +159,20 @@ void wifi_init() {
 	netif_init();
 
 	wifi_init_config_t cfg = WIFI_INIT_CONFIG_DEFAULT();
+	// It seems that ptc06 also uses nvs, and since both are in different tasks during init, we get a crash,
+	// which I think is caused by both trying to access/modify nvs at the "same" time
+	// I couldn't figure out a good/proper mechanism for interlocking, since I don't entirely know when and why
+	// both access nvs, but this will do
+	cfg.nvs_enable = false;
 	ESP_ERROR_CHECK(esp_wifi_init(&cfg));
 
 	wifi_init_events();
+	ESP_ERROR_CHECK(esp_wifi_set_mode(WIFI_MODE_STA));
 }
 
-void wifi_start() {
+void wifi_launch() {
 	ESP_ERROR_CHECK(esp_wifi_start());
 
-	if (!connect_to_open()) {
-		ESP_LOGI(TAG, "Couldn't find open network, connecting to configured net");
-		wifi_connect_station(ESP_WIFI_SSID, ESP_WIFI_SCAN_AUTH_MODE_THRESHOLD, ESP_WIFI_PASS);
-	}
+	xTaskCreate(launcher_scan_and_connect_task, "launcher_scan_and_connect_task", 768, NULL, 10, &launcher_handle);
+	xTaskNotify(launcher_handle, TO_CONNECT_BIT, eSetBits);
 }
diff --git a/Year 3/Internet of things/goam/main/wifi.h b/Year 3/Internet of things/goam/main/wifi.h
index 9c23266..f4e312a 100644
--- a/Year 3/Internet of things/goam/main/wifi.h
+++ b/Year 3/Internet of things/goam/main/wifi.h
@@ -1,4 +1,4 @@
 #pragma once
 
 void wifi_init();
-void wifi_start();
+void wifi_launch();