ESP8266_RTOS_SDK/examples/protocols/mdns/main/mdns_example_main.c

/* MDNS-SD Query and advertise Example

   This example code is in the Public Domain (or CC0 licensed, at your option.)

   Unless required by applicable law or agreed to in writing, this
   software is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR
   CONDITIONS OF ANY KIND, either express or implied.
*/
#include <string.h>
#include <sys/socket.h>
#include <netdb.h>

#include "freertos/FreeRTOS.h"
#include "freertos/task.h"
#include "esp_system.h"
#include "esp_log.h"
#include "esp_netif.h"
#include "esp_event.h"
#include "protocol_examples_common.h"
#include "nvs.h"
#include "nvs_flash.h"
#include "driver/gpio.h"

#include "mdns.h"

#define EXAMPLE_MDNS_HOSTNAME CONFIG_MDNS_HOSTNAME
#define EXAMPLE_MDNS_INSTANCE CONFIG_MDNS_INSTANCE

static const char *TAG = "mdns-test";

static void initialise_mdns(void)
{
    //initialize mDNS
    ESP_ERROR_CHECK( mdns_init() );
    //set mDNS hostname (required if you want to advertise services)
    ESP_ERROR_CHECK( mdns_hostname_set(EXAMPLE_MDNS_HOSTNAME) );
    //set default mDNS instance name
    ESP_ERROR_CHECK( mdns_instance_name_set(EXAMPLE_MDNS_INSTANCE) );

    //structure with TXT records
    mdns_txt_item_t serviceTxtData[3] = {
        {"board","esp32"},
        {"u","user"},
        {"p","password"}
    };

    //initialize service
    ESP_ERROR_CHECK( mdns_service_add("ESP32-WebServer", "_http", "_tcp", 80, serviceTxtData, 3) );
    //add another TXT item
    ESP_ERROR_CHECK( mdns_service_txt_item_set("_http", "_tcp", "path", "/foobar") );
    //change TXT item value
    ESP_ERROR_CHECK( mdns_service_txt_item_set("_http", "_tcp", "u", "admin") );
}

static const char * if_str[] = {"STA", "AP", "ETH", "MAX"};
static const char * ip_protocol_str[] = {"V4", "V6", "MAX"};

static void mdns_print_results(mdns_result_t * results){
    mdns_result_t * r = results;
    mdns_ip_addr_t * a = NULL;
    int i = 1, t;
    while(r){
        printf("%d: Interface: %s, Type: %s\n", i++, if_str[r->tcpip_if], ip_protocol_str[r->ip_protocol]);
        if(r->instance_name){
            printf("  PTR : %s\n", r->instance_name);
        }
        if(r->hostname){
            printf("  SRV : %s.local:%u\n", r->hostname, r->port);
        }
        if(r->txt_count){
            printf("  TXT : [%u] ", r->txt_count);
            for(t=0; t<r->txt_count; t++){
                printf("%s=%s; ", r->txt[t].key, r->txt[t].value?r->txt[t].value:"NULL");
            }
            printf("\n");
        }
        a = r->addr;
        while(a){
            if(a->addr.type == IPADDR_TYPE_V6){
                printf("  AAAA: " IPV6STR "\n", IPV62STR(a->addr.u_addr.ip6));
            } else {
                printf("  A   : " IPSTR "\n", IP2STR(&(a->addr.u_addr.ip4)));
            }
            a = a->next;
        }
        r = r->next;
    }

}

static void query_mdns_service(const char * service_name, const char * proto)
{
    ESP_LOGI(TAG, "Query PTR: %s.%s.local", service_name, proto);

    mdns_result_t * results = NULL;
    esp_err_t err = mdns_query_ptr(service_name, proto, 3000, 20,  &results);
    if(err){
        ESP_LOGE(TAG, "Query Failed: %s", esp_err_to_name(err));
        return;
    }
    if(!results){
        ESP_LOGW(TAG, "No results found!");
        return;
    }

    mdns_print_results(results);
    mdns_query_results_free(results);
}

static void query_mdns_host(const char * host_name)
{
    ESP_LOGI(TAG, "Query A: %s.local", host_name);

    struct ip4_addr addr;
    addr.addr = 0;

    esp_err_t err = mdns_query_a(host_name, 2000,  &addr);
    if(err){
        if(err == ESP_ERR_NOT_FOUND){
            ESP_LOGW(TAG, "%s: Host was not found!", esp_err_to_name(err));
            return;
        }
        ESP_LOGE(TAG, "Query Failed: %s", esp_err_to_name(err));
        return;
    }

    ESP_LOGI(TAG, IPSTR, IP2STR(&addr));
}

static void initialise_button(void)
{
    gpio_config_t io_conf;
    io_conf.intr_type = GPIO_INTR_DISABLE;
    io_conf.pin_bit_mask = 1;
    io_conf.mode = GPIO_MODE_INPUT;
    io_conf.pull_up_en = 1;
    io_conf.pull_down_en = 0;
    gpio_config(&io_conf);
}

static void check_button(void)
{
    static bool old_level = true;
    bool new_level = gpio_get_level(GPIO_NUM_0);
    if (!new_level && old_level) {
        query_mdns_host("esp32");
        query_mdns_service("_arduino", "_tcp");
        query_mdns_service("_http", "_tcp");
        query_mdns_service("_printer", "_tcp");
        query_mdns_service("_ipp", "_tcp");
        query_mdns_service("_afpovertcp", "_tcp");
        query_mdns_service("_smb", "_tcp");
        query_mdns_service("_ftp", "_tcp");
        query_mdns_service("_nfs", "_tcp");
    }
    old_level = new_level;
}

static void mdns_example_task(void *pvParameters)
{
    while(1) {
        check_button();
        vTaskDelay(50 / portTICK_PERIOD_MS);
    }
}

void app_main()
{
    ESP_ERROR_CHECK(nvs_flash_init());
    ESP_ERROR_CHECK(esp_netif_init());
    ESP_ERROR_CHECK(esp_event_loop_create_default());

    ESP_ERROR_CHECK(example_connect());

    initialise_mdns();
    initialise_button();

    xTaskCreate(&mdns_example_task, "mdns_example_task", 2048, NULL, 5, NULL);
}