blinky-esp/main/wifi.cpp

static const char *TAG = "WiFi";
#include "esp_log.h"


#include "wifi.hpp"

// Defines SSID and PASS
#include "wifi_cfg.hpp"

static const int CONFIG_ESP_MAXIMUM_RETRY = 3;


#include "esp_wifi.h"
#include "freertos/event_groups.h"

static EventGroupHandle_t s_wifi_event_group;

#define WIFI_CONNECTED_BIT BIT0
#define WIFI_FAIL_BIT      BIT1

static void event_handler(void* arg, esp_event_base_t event_base,
                                int32_t event_id, void* event_data) {
    static int s_retry_num = 0;

    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) {
        ESP_LOGI(TAG, "Disconnected, retrying connection to AP");
        esp_wifi_connect();

    } 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 address: " IPSTR, IP2STR(&event->ip_info.ip));
        s_retry_num = 0;
        xEventGroupSetBits(s_wifi_event_group, WIFI_CONNECTED_BIT);
    }
}

int config_wifi() {
    ESP_LOGI(TAG, "Connecting to %s", SSID);

    s_wifi_event_group = xEventGroupCreate();

    ESP_ERROR_CHECK(esp_netif_init());

    ESP_ERROR_CHECK(esp_event_loop_create_default());
    esp_netif_create_default_wifi_sta();

    wifi_init_config_t cfg = WIFI_INIT_CONFIG_DEFAULT();
    ESP_ERROR_CHECK(esp_wifi_init(&cfg));

    esp_event_handler_instance_t instance_any_id;
    esp_event_handler_instance_t instance_got_ip;
    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 = SSID,
            .password = PASS,
        },
    };

    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() );

/*
    // 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: %s", SSID);
        return 0;

    } else if (bits & WIFI_FAIL_BIT) {
        ESP_LOGE(TAG, "Failed to connect to SSID %s", SSID);
    } else {
        ESP_LOGE(TAG, "UNEXPECTED EVENT");
    }
*/

    return 0;
}