added dns function check

main/main.c

@@ -18,6 +18,9 @@
 #include "driver/gpio.h"
 #include <driver/adc.h>
 #include "sdkconfig.h"
+#include "lwip/inet.h"
+#include "lwip/netdb.h"
+#include "lwip/sockets.h"
 
 #include "ssd1306.h"
 #include "font8x8_basic.h"
@@ -46,7 +49,7 @@ esp_ip4_addr_t ip_snm;
 esp_ip4_addr_t ip_gw;
 esp_netif_t *eth_netif;
 
-bool dns_resolv = false;
+int dns_resolv = -1;
 
 bool blink_mod = false;
 
@@ -57,16 +60,28 @@ static uint8_t get_byte(uint32_t addr, int n)
 
 #define IP4ZCHK(ipaddr) (esp_ip4_addr1_16(ipaddr) | esp_ip4_addr2_16(ipaddr) | esp_ip4_addr3_16(ipaddr) | esp_ip4_addr4_16(ipaddr))
 
-static bool check_dns()
+static int check_dns()
 {
     esp_netif_dns_info_t dns_info;
     ESP_ERROR_CHECK(esp_netif_get_dns_info(eth_netif, ESP_NETIF_DNS_MAIN, &dns_info));
     // ESP_LOGI(TAG, IP_FSTRING, IP2STR(&dns_info.ip.u_addr.ip4));
     // ESP_LOGI(TAG, "%d", IP4ZCHK(&dns_info.ip.u_addr.ip4));
 
+
     if (IP4ZCHK(&dns_info.ip.u_addr.ip4) != 0)
-        return true;
-    return false;
+        return 1;
+    return 0;
+}
+
+static void check_resolution(void *arg)
+{
+    struct addrinfo hint;
+    struct addrinfo *res = NULL;
+    memset(&hint, 0, sizeof(hint));
+    while (1) {
+        dns_resolv = getaddrinfo("www.google.de", NULL, &hint, &res);
+        vTaskDelay(250 / portTICK_RATE_MS);
+    }
 }
 
 static void refresh_display()
@@ -136,8 +151,10 @@ static void refresh_display()
     bool poe = (adc1_get_raw(ADC1_CHANNEL_3) > 2048); //arbitrary value, battery power is ~800
     bool eth = (eth_state == ETHERNET_EVENT_CONNECTED);
     bool addr = (ip_addr.addr != 0) & eth;
-    bool dns = ((check_dns()) && addr && blink_mod) || dns_resolv;
+    bool dns = ((check_dns()) && addr && blink_mod) || (dns_resolv == 0);
     
+    
+    ssd1306_clear_line(&display, LINE_STATUS_FLAGS3, false);
     ssd1306_display_text(&display, LINE_STATUS_FLAGS3, "POE", 3, poe, 13);
     ssd1306_display_text(&display, LINE_STATUS_FLAGS3, "LNK", 3, eth, 9);
     ssd1306_display_text(&display, LINE_STATUS_FLAGS3, "DHCP", 4, addr, 4);
@@ -162,12 +179,14 @@ static void eth_event_handler(void *arg, esp_event_base_t event_base,
         break;
     case ETHERNET_EVENT_DISCONNECTED:
         ESP_LOGI(TAG, "Link Down");
+        dns_resolv = -1;
         break;
     case ETHERNET_EVENT_START:
         ESP_LOGI(TAG, "Ethernet Started");
         break;
     case ETHERNET_EVENT_STOP:
         ESP_LOGI(TAG, "Ethernet Stopped");
+        dns_resolv = -1;
         break;
     default:
         break;
@@ -222,6 +241,35 @@ static void task_signals(void* arg)
     }
 }
 
+// void icmp_ping(in_addr_t ip)
+// {
+//     /* convert URL to IP address */
+//     ip_addr_t target_addr;
+//     struct addrinfo hint;
+//     struct addrinfo *res = NULL;
+//     memset(&hint, 0, sizeof(hint));
+//     memset(&target_addr, 0, sizeof(target_addr));
+//     getaddrinfo("www.espressif.com", NULL, &hint, &res);
+//     struct in_addr addr4 = ((struct sockaddr_in *) (res->ai_addr))->sin_addr;
+//     inet_addr_to_ip4addr(ip_2_ip4(&target_addr), &addr4);
+//     freeaddrinfo(res);
+
+//     esp_ping_config_t ping_config = ESP_PING_DEFAULT_CONFIG();
+//     ping_config.target_addr = target_addr;          // target IP address
+//     ping_config.count = ESP_PING_COUNT_INFINITE;    // ping in infinite mode, esp_ping_stop can stop it
+
+//     /* set callback functions */
+//     esp_ping_callbacks_t cbs;
+//     cbs.on_ping_success = test_on_ping_success;
+//     cbs.on_ping_timeout = test_on_ping_timeout;
+//     cbs.on_ping_end = test_on_ping_end;
+//     cbs.cb_args = "foo";  // arguments that will feed to all callback functions, can be NULL
+//     cbs.cb_args = eth_event_group;
+
+//     esp_ping_handle_t ping;
+//     esp_ping_new_session(&ping_config, &cbs, &ping);
+// }
+
 #define	PIN_PHY_POWER	12					
 void app_main(void)
 {
@@ -350,7 +398,7 @@ void app_main(void)
     adc1_config_channel_atten(ADC1_CHANNEL_3, ADC_ATTEN_DB_11);
 
     // gpio setup
-        //zero-initialize the config structure.
+    //zero-initialize the config structure.
     gpio_config_t io_conf = {};
 
     //interrupt of rising edge
@@ -372,7 +420,11 @@ void app_main(void)
     //start signal task
     xTaskCreate(task_signals, "signals", 2048, NULL, 10, NULL);
 
+    // start task to continually check dns resolution
+    xTaskCreate(check_resolution, "dns_res", 2048, NULL, 10, NULL);
 
+    // continuously refresh display
+    // not all events trigger refreshing the disply
     while (1) {
         blink_mod = !blink_mod;
         refresh_display();