esp-open-rtos/examples/access_point/access_point.c

/**
 * Very basic example showing usage of access point mode and the DHCP server.
 * The ESP in the example runs a telnet server on 172.16.0.1 (port 23) that
 * outputs some status information if you connect to it, then closes
 * the connection.
 *
 * This example code is in the public domain.
 */
#include <string.h>

#include <espressif/esp_common.h>
#include <esp/uart.h>
#include <FreeRTOS.h>
#include <task.h>
#include <queue.h>
#include <dhcpserver.h>

#include <lwip/api.h>

#define AP_SSID "esp-open-rtos AP"
#define AP_PSK "esp-open-rtos"

#define TELNET_PORT 23

static void telnetTask(void *pvParameters);

void user_init(void)
{
    uart_set_baud(0, 115200);
    printf("SDK version:%s\n", sdk_system_get_sdk_version());

    sdk_wifi_set_opmode(SOFTAP_MODE);
    struct ip_info ap_ip;
    IP4_ADDR(&ap_ip.ip, 172, 16, 0, 1);
    IP4_ADDR(&ap_ip.gw, 0, 0, 0, 0);
    IP4_ADDR(&ap_ip.netmask, 255, 255, 0, 0);
    sdk_wifi_set_ip_info(1, &ap_ip);

    struct sdk_softap_config ap_config = { .ssid = AP_SSID, .ssid_hidden = 0, .channel = 3, .ssid_len = strlen(AP_SSID), .authmode =
            AUTH_WPA_WPA2_PSK, .password = AP_PSK, .max_connection = 3, .beacon_interval = 100, };
    sdk_wifi_softap_set_config(&ap_config);

    xTaskCreate(telnetTask, "telnetTask", 512, NULL, 2, NULL);
}

/* Telnet task listens on port 23, returns some status information and then closes
 the connection if you connect to it.
 */
static void telnetTask(void *pvParameters)
{
    ip_addr_t first_client_ip;
    IP4_ADDR(&first_client_ip, 172, 16, 0, 2);
    dhcpserver_start(&first_client_ip, 4);

    struct netconn *nc = netconn_new(NETCONN_TCP);
    if (!nc)
    {
        printf("Status monitor: Failed to allocate socket.\r\n");
        return;
    }
    netconn_bind(nc, IP_ANY_TYPE, TELNET_PORT);
    netconn_listen(nc);

    while (1)
    {
        struct netconn *client = NULL;
        err_t err = netconn_accept(nc, &client);

        if (err != ERR_OK)
        {
            if (client)
                netconn_delete(client);
            continue;
        }

        ip_addr_t client_addr;
        uint16_t port_ignore;
        netconn_peer(client, &client_addr, &port_ignore);

        char buf[80];
        snprintf(buf, sizeof(buf), "Uptime %d seconds\r\n", xTaskGetTickCount() * portTICK_PERIOD_MS / 1000);
        netconn_write(client, buf, strlen(buf), NETCONN_COPY);
        snprintf(buf, sizeof(buf), "Free heap %d bytes\r\n", (int) xPortGetFreeHeapSize());
        netconn_write(client, buf, strlen(buf), NETCONN_COPY);
        char abuf[40];
        snprintf(buf, sizeof(buf), "Your address is %s\r\n\r\n", ipaddr_ntoa_r(&client_addr, abuf, sizeof(abuf)));
        netconn_write(client, buf, strlen(buf), NETCONN_COPY);
        netconn_delete(client);
    }
}