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 <espressif/sdk_private.h>
#include <sdk_internal.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)
{
    sdk_uart_div_modify(0, UART_CLK_FREQ / 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);

    ip_addr_t first_client_ip;
    IP4_ADDR(&first_client_ip, 172, 16, 0, 2);
    dhcpserver_start(&first_client_ip, 4);

    xTaskCreate(telnetTask, (signed char *)"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)
{
  struct netconn *nc = netconn_new (NETCONN_TCP);
  if(!nc) {
    printf("Status monitor: Failed to allocate socket.\r\n");
    return;
  }
  netconn_bind(nc, IP_ADDR_ANY, 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_RATE_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);
    snprintf(buf, sizeof(buf), "Your address is %d.%d.%d.%d\r\n\r\n",
             ip4_addr1(&client_addr), ip4_addr2(&client_addr),
             ip4_addr3(&client_addr), ip4_addr4(&client_addr));
    netconn_write(client, buf, strlen(buf), NETCONN_COPY);
    netconn_delete(client);
  }
}