advait_projects/station/main/station_example_main.c
2025-04-07 19:29:01 -07:00

135 lines
4.7 KiB
C

#include <string.h>
#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "freertos/event_groups.h"
#include "esp_system.h"
#include "esp_wifi.h"
#include "esp_event.h"
#include "esp_log.h"
#include "nvs_flash.h"
#include "nvs.h"
#include "lwip/err.h"
#include "lwip/sys.h"
#define WIFI_SSID_MAX_LEN 32
#define WIFI_PASS_MAX_LEN 64
#define MAX_RETRY 5
static EventGroupHandle_t s_wifi_event_group;
#define WIFI_CONNECTED_BIT BIT0
#define WIFI_FAIL_BIT BIT1
static const char *TAG = "wifi_nvm_sta";
static int s_retry_num = 0;
void save_wifi_creds(const char *ssid, const char *pass) {
nvs_handle_t nvs_handle;
ESP_ERROR_CHECK(nvs_open("wifi_creds", NVS_READWRITE, &nvs_handle));
ESP_ERROR_CHECK(nvs_set_str(nvs_handle, "ssid", ssid));
ESP_ERROR_CHECK(nvs_set_str(nvs_handle, "pass", pass));
ESP_ERROR_CHECK(nvs_commit(nvs_handle));
nvs_close(nvs_handle);
ESP_LOGI(TAG, "WiFi credentials saved");
}
bool load_wifi_creds(char *ssid, size_t ssid_len, char *pass, size_t pass_len) {
nvs_handle_t nvs_handle;
esp_err_t err = nvs_open("wifi_creds", NVS_READONLY, &nvs_handle);
if (err != ESP_OK) return false;
err = nvs_get_str(nvs_handle, "ssid", ssid, &ssid_len);
if (err != ESP_OK) {
nvs_close(nvs_handle);
return false;
}
err = nvs_get_str(nvs_handle, "pass", pass, &pass_len);
nvs_close(nvs_handle);
return err == ESP_OK;
}
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 < MAX_RETRY) {
esp_wifi_connect();
s_retry_num++;
ESP_LOGI(TAG, "retrying connection to AP");
} else {
xEventGroupSetBits(s_wifi_event_group, WIFI_FAIL_BIT);
}
ESP_LOGI(TAG,"failed to connect to AP");
} 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);
}
}
void wifi_init_sta(void) {
char ssid[WIFI_SSID_MAX_LEN] = {0};
char pass[WIFI_PASS_MAX_LEN] = {0};
bool creds_loaded = load_wifi_creds(ssid, sizeof(ssid), pass, sizeof(pass));
if (!creds_loaded) {
// Default open network: UCLA_WIFI
strcpy(ssid, "UCLA_WIFI");
pass[0] = '\0'; // No password
save_wifi_creds(ssid, pass);
}
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 = { 0 };
strncpy((char *)wifi_config.sta.ssid, ssid, sizeof(wifi_config.sta.ssid));
strncpy((char *)wifi_config.sta.password, pass, sizeof(wifi_config.sta.password));
wifi_config.sta.threshold.authmode = WIFI_AUTH_OPEN;
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.");
EventBits_t bits = xEventGroupWaitBits(s_wifi_event_group,
WIFI_CONNECTED_BIT | WIFI_FAIL_BIT,
pdFALSE,
pdFALSE,
portMAX_DELAY);
if (bits & WIFI_CONNECTED_BIT) {
ESP_LOGI(TAG, "connected to SSID:%s", ssid);
} else if (bits & WIFI_FAIL_BIT) {
ESP_LOGI(TAG, "Failed to connect to SSID:%s", ssid);
} else {
ESP_LOGE(TAG, "UNEXPECTED EVENT");
}
}
void app_main(void) {
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);
ESP_LOGI(TAG, "ESP_WIFI_MODE_STA");
wifi_init_sta();
}