Create wifi.c/h: create AP or connect to Wifi

Create functions in wifi.c and wifi.h:
- an wifi accesspoint can be created
- connect to an existing wifi anf disconnect

Add code for testing to main.cpp:
repeatedly connects, disconnects and switches between AP and connecting
to BKA-network every run

New functions
//init components (run in main function once)
  void wifi_initNvs_initNetif();
//function to start an access point
  void wifi_init_ap(void);
//function to disable/deinit access point
  void wifi_deinit_ap(void);

//function to connect to existing wifi network
  void wifi_init_client(void);
//function to disable/deinit client
  void wifi_deinit_client(void);

main/CMakeLists.txt

@@ -1,2 +1,2 @@
-idf_component_register(SRCS "main.cpp" "motordrivers.cpp" "motorctl.cpp" "config.cpp" "joystick.cpp" "buzzer.cpp" "control.cpp" "button.cpp" "fan.cpp"
+idf_component_register(SRCS "main.cpp" "motordrivers.cpp" "motorctl.cpp" "config.cpp" "joystick.cpp" "buzzer.cpp" "control.cpp" "button.cpp" "fan.cpp" "wifi.c"
                     INCLUDE_DIRS ".")

main/main.cpp

@@ -12,6 +12,7 @@ extern "C"
 
 #include "driver/ledc.h"
 
+#include "wifi.h"
 }
 
 #include "config.hpp"
@@ -105,6 +106,9 @@ extern "C" void app_main(void) {
     gpio_set_level(GPIO_NUM_17, 1);                                                      
 
 
+    //initialize nvs-flash and netif (needed for wifi)
+    wifi_initNvs_initNetif();
+
 
     //-------------------------------
     //---------- log level ----------
@@ -119,10 +123,10 @@ extern "C" void app_main(void) {
     //esp_log_level_set("joystickCommands", ESP_LOG_DEBUG);
     esp_log_level_set("button", ESP_LOG_INFO);
     esp_log_level_set("control", ESP_LOG_INFO);
-    esp_log_level_set("fan-control", ESP_LOG_DEBUG);
+    esp_log_level_set("fan-control", ESP_LOG_INFO);
-
+    esp_log_level_set("wifi", ESP_LOG_INFO);
-
 
+    
     //----------------------------------------------
     //--- create task for controlling the motors ---
     //----------------------------------------------
@@ -159,8 +163,25 @@ extern "C" void app_main(void) {
 
     while(1){
 
+
+
         vTaskDelay(500 / portTICK_PERIOD_MS);
 
+        //--- testing wifi functions ---
+        ESP_LOGI(TAG, "creating AP");
+        wifi_init_ap(); //start accesspoint
+        vTaskDelay(15000 / portTICK_PERIOD_MS);
+        ESP_LOGI(TAG, "stopping wifi");
+        wifi_deinit_ap();  //stop wifi access point
+        vTaskDelay(5000 / portTICK_PERIOD_MS);
+        ESP_LOGI(TAG, "connecting to wifi");
+        wifi_init_client(); //connect to existing wifi
+        vTaskDelay(10000 / portTICK_PERIOD_MS);
+        ESP_LOGI(TAG, "stopping wifi");
+        wifi_deinit_client(); //stop wifi client
+        vTaskDelay(5000 / portTICK_PERIOD_MS);
+
+
 
        //--- testing button ---
        //buttonJoystick.handle();

main/wifi.c

@@ -0,0 +1,257 @@
+#include <string.h>
+#include "freertos/FreeRTOS.h"
+#include "freertos/task.h"
+#include "freertos/event_groups.h"
+#include "esp_system.h"
+#include "esp_mac.h"
+#include "esp_wifi.h"
+#include "esp_event.h"
+#include "esp_log.h"
+#include "nvs_flash.h"
+
+#include "lwip/err.h"
+#include "lwip/sys.h"
+
+#include "wifi.h"
+
+
+
+//--- variables used for ap and wifi ---
+static const char *TAG = "wifi";
+static esp_event_handler_instance_t instance_any_id;
+
+
+//============================================
+//============ init nvs and netif ============
+//============================================
+//initialize nvs-flash and netif (needed for both AP and CLIENT)
+//has to be run once at startup 
+void wifi_initNvs_initNetif(){
+    //Initialize NVS (needed for wifi)
+    esp_err_t ret = nvs_flash_init();
+    if (ret == ESP_ERR_NVS_NO_FREE_PAGES || ret == ESP_ERR_NVS_NEW_VERSION_FOUND) {
+        ESP_ERROR_CHECK(nvs_flash_erase());
+        ret = nvs_flash_init();
+    }
+    ESP_ERROR_CHECK(esp_netif_init());
+    ESP_ERROR_CHECK(esp_event_loop_create_default());
+}
+
+
+//===========================================
+//============ init access point ============
+//===========================================
+
+//--------------------------------------------
+//------ configuration / declarations --------
+//--------------------------------------------
+#define EXAMPLE_ESP_WIFI_SSID_AP      "armchair"
+#define EXAMPLE_ESP_WIFI_PASS_AP      ""
+#define EXAMPLE_ESP_WIFI_CHANNEL_AP   1
+#define EXAMPLE_MAX_STA_CONN_AP       4
+
+static esp_netif_t *ap;
+
+static void wifi_event_handler_ap(void* arg, esp_event_base_t event_base,
+        int32_t event_id, void* event_data)
+{
+    if (event_id == WIFI_EVENT_AP_STACONNECTED) {
+        wifi_event_ap_staconnected_t* event = (wifi_event_ap_staconnected_t*) event_data;
+        ESP_LOGI(TAG, "station "MACSTR" join, AID=%d",
+                MAC2STR(event->mac), event->aid);
+    } else if (event_id == WIFI_EVENT_AP_STADISCONNECTED) {
+        wifi_event_ap_stadisconnected_t* event = (wifi_event_ap_stadisconnected_t*) event_data;
+        ESP_LOGI(TAG, "station "MACSTR" leave, AID=%d",
+                MAC2STR(event->mac), event->aid);
+    }
+}
+
+//-----------------------
+//------ init ap --------
+//-----------------------
+void wifi_init_ap(void)
+{
+    ap = esp_netif_create_default_wifi_ap();
+
+    wifi_init_config_t cfg = WIFI_INIT_CONFIG_DEFAULT();
+    ESP_ERROR_CHECK(esp_wifi_init(&cfg));
+
+    ESP_ERROR_CHECK(esp_event_handler_instance_register(WIFI_EVENT,
+                ESP_EVENT_ANY_ID,
+                &wifi_event_handler_ap,
+                NULL,
+                &instance_any_id));
+
+    wifi_config_t wifi_config = {
+        .ap = {
+            .ssid = EXAMPLE_ESP_WIFI_SSID_AP,
+            .ssid_len = strlen(EXAMPLE_ESP_WIFI_SSID_AP),
+            .channel = EXAMPLE_ESP_WIFI_CHANNEL_AP,
+            .password = EXAMPLE_ESP_WIFI_PASS_AP,
+            .max_connection = EXAMPLE_MAX_STA_CONN_AP,
+            .authmode = WIFI_AUTH_WPA_WPA2_PSK
+        },
+    };
+    if (strlen(EXAMPLE_ESP_WIFI_PASS_AP) == 0) {
+        wifi_config.ap.authmode = WIFI_AUTH_OPEN;
+    }
+
+    ESP_ERROR_CHECK(esp_wifi_set_mode(WIFI_MODE_AP));
+    ESP_ERROR_CHECK(esp_wifi_set_config(WIFI_IF_AP, &wifi_config));
+    ESP_ERROR_CHECK(esp_wifi_start());
+
+    ESP_LOGI(TAG, "wifi_init_softap finished. SSID:%s password:%s channel:%d",
+            EXAMPLE_ESP_WIFI_SSID_AP, EXAMPLE_ESP_WIFI_PASS_AP, EXAMPLE_ESP_WIFI_CHANNEL_AP);
+}
+
+
+
+//=============================
+//========= deinit AP =========
+//=============================
+void wifi_deinit_ap(void)
+{
+    ESP_ERROR_CHECK(esp_event_handler_instance_unregister(WIFI_EVENT, ESP_EVENT_ANY_ID, instance_any_id));
+    ESP_ERROR_CHECK(esp_event_handler_instance_unregister(WIFI_EVENT, ESP_EVENT_ANY_ID, instance_any_id));
+    esp_wifi_stop();
+    esp_wifi_deinit();
+    esp_netif_destroy_default_wifi(ap);
+
+}
+
+
+
+
+
+
+
+
+
+
+
+
+//===========================================
+//=============== init client ===============
+//===========================================
+
+//--------------------------------------------
+//------ configuration / declarations --------
+//--------------------------------------------
+#define EXAMPLE_ESP_WIFI_SSID_CLIENT      "BKA-network"
+#define EXAMPLE_ESP_WIFI_PASS_CLIENT      "airwaveslogitech410"
+#define EXAMPLE_ESP_MAXIMUM_RETRY_CLIENT  10
+
+static esp_netif_t *sta;
+static esp_event_handler_instance_t instance_got_ip;
+
+/* FreeRTOS event group to signal when we are connected*/
+static EventGroupHandle_t s_wifi_event_group;
+
+/* The event group allows multiple bits for each event, but we only care about two events:
+ * - we are connected to the AP with an IP
+ * - we failed to connect after the maximum amount of retries */
+#define WIFI_CONNECTED_BIT BIT0
+#define WIFI_FAIL_BIT      BIT1
+
+static int s_retry_num = 0;
+static void event_handler(void* arg, esp_event_base_t event_base,
+        int32_t event_id, void* event_data)
+{
+    if (event_base == WIFI_EVENT && event_id == WIFI_EVENT_STA_START) {
+        esp_wifi_connect();
+    } else if (event_base == WIFI_EVENT && event_id == WIFI_EVENT_STA_DISCONNECTED) {
+        if (s_retry_num < EXAMPLE_ESP_MAXIMUM_RETRY_CLIENT) {
+            esp_wifi_connect();
+            s_retry_num++;
+            ESP_LOGI(TAG, "retry to connect to the AP");
+        } else {
+            xEventGroupSetBits(s_wifi_event_group, WIFI_FAIL_BIT);
+        }
+        ESP_LOGI(TAG,"connect to the AP fail");
+    } else if (event_base == IP_EVENT && event_id == IP_EVENT_STA_GOT_IP) {
+        ip_event_got_ip_t* event = (ip_event_got_ip_t*) event_data;
+        ESP_LOGI(TAG, "got ip:" IPSTR, IP2STR(&event->ip_info.ip));
+        s_retry_num = 0;
+        xEventGroupSetBits(s_wifi_event_group, WIFI_CONNECTED_BIT);
+    }
+}
+//---------------------------
+//------ init client --------
+//---------------------------
+void wifi_init_client(void)
+{
+    s_wifi_event_group = xEventGroupCreate();
+    sta = esp_netif_create_default_wifi_sta();
+
+    wifi_init_config_t cfg = WIFI_INIT_CONFIG_DEFAULT();
+    ESP_ERROR_CHECK(esp_wifi_init(&cfg));
+
+    ESP_ERROR_CHECK(esp_event_handler_instance_register(WIFI_EVENT,
+                ESP_EVENT_ANY_ID,
+                &event_handler,
+                NULL,
+                &instance_any_id));
+    ESP_ERROR_CHECK(esp_event_handler_instance_register(IP_EVENT,
+                IP_EVENT_STA_GOT_IP,
+                &event_handler,
+                NULL,
+                &instance_got_ip));
+
+    wifi_config_t wifi_config = {
+        .sta = {
+            .ssid = EXAMPLE_ESP_WIFI_SSID_CLIENT,
+            .password = EXAMPLE_ESP_WIFI_PASS_CLIENT,
+            /* Setting a password implies station will connect to all security modes including WEP/WPA.
+             * However these modes are deprecated and not advisable to be used. Incase your Access point
+             * doesn't support WPA2, these mode can be enabled by commenting below line */
+            .threshold.authmode = WIFI_AUTH_WPA2_PSK,
+        },
+    };
+    ESP_ERROR_CHECK(esp_wifi_set_mode(WIFI_MODE_STA) );
+    ESP_ERROR_CHECK(esp_wifi_set_config(WIFI_IF_STA, &wifi_config) );
+    ESP_ERROR_CHECK(esp_wifi_start() );
+
+    ESP_LOGI(TAG, "wifi_init_sta finished.");
+
+    /* Waiting until either the connection is established (WIFI_CONNECTED_BIT) or connection failed for the maximum
+     * number of re-tries (WIFI_FAIL_BIT). The bits are set by event_handler() (see above) */
+    EventBits_t bits = xEventGroupWaitBits(s_wifi_event_group,
+            WIFI_CONNECTED_BIT | WIFI_FAIL_BIT,
+            pdFALSE,
+            pdFALSE,
+            portMAX_DELAY);
+
+    /* xEventGroupWaitBits() returns the bits before the call returned, hence we can test which event actually
+     * happened. */
+    if (bits & WIFI_CONNECTED_BIT) {
+        ESP_LOGI(TAG, "connected to ap SSID:%s password:%s",
+                EXAMPLE_ESP_WIFI_SSID_CLIENT, EXAMPLE_ESP_WIFI_PASS_CLIENT);
+    } else if (bits & WIFI_FAIL_BIT) {
+        ESP_LOGI(TAG, "Failed to connect to SSID:%s, password:%s",
+                EXAMPLE_ESP_WIFI_SSID_CLIENT, EXAMPLE_ESP_WIFI_PASS_CLIENT);
+    } else {
+        ESP_LOGE(TAG, "UNEXPECTED EVENT");
+    }
+
+    //    /* The event will not be processed after unregister */
+    //    ESP_ERROR_CHECK(esp_event_handler_instance_unregister(IP_EVENT, IP_EVENT_STA_GOT_IP, instance_got_ip));
+    //    ESP_ERROR_CHECK(esp_event_handler_instance_unregister(WIFI_EVENT, ESP_EVENT_ANY_ID, instance_any_id));
+    //    vEventGroupDelete(s_wifi_event_group);
+}
+
+
+
+//=================================
+//========= deinit client =========
+//=================================
+void wifi_deinit_client(void)
+{
+    /* The event will not be processed after unregister */
+    ESP_ERROR_CHECK(esp_event_handler_instance_unregister(IP_EVENT, IP_EVENT_STA_GOT_IP, instance_got_ip));
+    ESP_ERROR_CHECK(esp_event_handler_instance_unregister(WIFI_EVENT, ESP_EVENT_ANY_ID, instance_any_id));
+    vEventGroupDelete(s_wifi_event_group);
+    esp_wifi_stop();
+    esp_wifi_deinit();
+    esp_netif_destroy_default_wifi(sta);
+}
+

main/wifi.h

@@ -0,0 +1,22 @@
+#pragma once
+
+//TODO: currently wifi names and passwords are configured in wifi.c -> move this to config?
+
+//initialize nvs-flash and netif (needed for both AP and CLIENT)
+//has to be run once at startup 
+//Note: this cant be put in wifi_init functions because this may not be in deinit functions
+void wifi_initNvs_initNetif();
+
+
+//function to start an access point
+void wifi_init_ap(void);
+//function to disable/deinit access point
+void wifi_deinit_ap(void);
+
+//function to connect to existing wifi network
+void wifi_init_client(void);
+//function to disable/deinit client
+void wifi_deinit_client(void);
+
+
+