wifi_sta.c

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/*
 * MIT License
 *
 * Copyright (c) 2021 wolffshots
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in all
 * copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
 * SOFTWARE.
 * 
 * A note on the copyright line: https://www.copyright.gov/title17/92chap4.html#408
 */
 
#include "wifi_sta.h"
 
/* FreeRTOS event group to signal when we are connected*/
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
 
const char *TAG = CONFIG_WIFI_SAP_LOG_TAG;
int s_retry_num = 0;
void event_handler(void *arg, esp_event_base_t event_base,
                   int32_t event_id, void *event_data);
void wifi_init_sta(void);
 
void event_handler(void *arg, esp_event_base_t event_base,
                   int32_t event_id, void *event_data)
{
#ifdef CONFIG_ESP_MAXIMUM_RETRY_STA
    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 < CONFIG_ESP_MAXIMUM_RETRY_STA)
        {
            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));
        sprintf(ip_address, IPSTR, IP2STR(&event->ip_info.ip));
        s_retry_num = 0;
        xEventGroupSetBits(s_wifi_event_group, WIFI_CONNECTED_BIT);
    }
#endif
}
void wifi_init_station(void)
{
#if defined(CONFIG_ESP_WIFI_SSID_STA) && defined(CONFIG_ESP_WIFI_PASSWORD_STA)
    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 = CONFIG_ESP_WIFI_SSID_STA,
            .password = CONFIG_ESP_WIFI_PASSWORD_STA,
            /* 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,
            .pmf_cfg = {
                .capable = true,
                .required = false},
        },
    };
    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);
 
    // hide after first 2 chars
    char pass[6];
    if (strlen(CONFIG_ESP_WIFI_PASSWORD_STA) > 5)
    {
        char str2[40];
        strncpy(str2, CONFIG_ESP_WIFI_PASSWORD_STA, sizeof(str2));
        strncpy(pass, str2, 2);
    }
    else
    {
        pass[0] = '*';
        pass[1] = '*';
    }
    pass[2] = '*';
    pass[3] = '*';
    pass[4] = '*';
    pass[5] = '\0';
    /* 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",
                 CONFIG_ESP_WIFI_SSID_STA, pass);
    }
    else if (bits & WIFI_FAIL_BIT)
    {
        ESP_LOGI(TAG, "Failed to connect to SSID: %s, password: %s",
                 CONFIG_ESP_WIFI_SSID_STA, pass);
    }
    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);
#endif
}
void wifi_init_sta()
{
    ESP_LOGI(TAG, "wifi station!");
    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(ret);
    wifi_init_station();
}