Merge branch 'feature/lwip_ipv6_only' into 'master'

lwip: Support IPv6 only mode

Closes IDF-6023

See merge request espressif/esp-idf!20468

examples/common_components/protocol_examples_common/Kconfig.projbuild

@@ -306,6 +306,11 @@ menu "Example Connection Configuration"
                 Set PHY address according your board schematic.
     endif # EXAMPLE_CONNECT_ETHERNET
 
+    config EXAMPLE_CONNECT_IPV4
+        bool
+        depends on LWIP_IPV4
+        default y
+
     config EXAMPLE_CONNECT_IPV6
         depends on EXAMPLE_CONNECT_WIFI || EXAMPLE_CONNECT_ETHERNET
         bool "Obtain IPv6 address"

examples/common_components/protocol_examples_common/addr_from_stdin.c

@@ -41,6 +41,7 @@ esp_err_t get_addr_from_stdin(int port, int sock_type, int *ip_protocol, int *ad
     }
     for( cur = addr_list; cur != NULL; cur = cur->ai_next ) {
         memcpy(dest_addr, cur->ai_addr, sizeof(*dest_addr));
+#if CONFIG_EXAMPLE_CONNECT_IPV4
         if (cur->ai_family == AF_INET) {
             *ip_protocol = IPPROTO_IP;
             *addr_family = AF_INET;
@@ -48,10 +49,10 @@ esp_err_t get_addr_from_stdin(int port, int sock_type, int *ip_protocol, int *ad
             ((struct sockaddr_in*)dest_addr)->sin_port = htons(port);
             freeaddrinfo( addr_list );
             return ESP_OK;
-
         }
+#endif // IPV4
 #if CONFIG_EXAMPLE_CONNECT_IPV6
-        else if (cur->ai_family == AF_INET6) {
+        if (cur->ai_family == AF_INET6) {
             *ip_protocol = IPPROTO_IPV6;
             *addr_family = AF_INET6;
             // add port and interface number and return on first IPv6 match
@@ -60,7 +61,7 @@ esp_err_t get_addr_from_stdin(int port, int sock_type, int *ip_protocol, int *ad
             freeaddrinfo( addr_list );
             return ESP_OK;
         }
-#endif
+#endif // IPV6
     }
     // no match found
     freeaddrinfo( addr_list );

examples/common_components/protocol_examples_common/connect.c

@@ -58,14 +58,16 @@ void example_print_all_netif_ips(const char *prefix)
 {
     // iterate over active interfaces, and print out IPs of "our" netifs
     esp_netif_t *netif = NULL;
-    esp_netif_ip_info_t ip;
     for (int i = 0; i < esp_netif_get_nr_of_ifs(); ++i) {
         netif = esp_netif_next(netif);
         if (example_is_our_netif(prefix, netif)) {
             ESP_LOGI(TAG, "Connected to %s", esp_netif_get_desc(netif));
+#if CONFIG_LWIP_IPV4
+            esp_netif_ip_info_t ip;
             ESP_ERROR_CHECK(esp_netif_get_ip_info(netif, &ip));
 
             ESP_LOGI(TAG, "- IPv4 address: " IPSTR ",", IP2STR(&ip.ip));
+#endif
 #if CONFIG_EXAMPLE_CONNECT_IPV6
             esp_ip6_addr_t ip6[MAX_IP6_ADDRS_PER_NETIF];
             int ip6_addrs = esp_netif_get_all_ip6(netif, ip6);

examples/common_components/protocol_examples_common/eth_connect.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2022 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2022-2023 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Unlicense OR CC0-1.0
  */
@@ -214,10 +214,12 @@ void example_ethernet_shutdown(void)
 
 esp_err_t example_ethernet_connect(void)
 {
+#if CONFIG_EXAMPLE_CONNECT_IPV4
     s_semph_get_ip_addrs = xSemaphoreCreateBinary();
     if (s_semph_get_ip_addrs == NULL) {
         return ESP_ERR_NO_MEM;
     }
+#endif
 #if CONFIG_EXAMPLE_CONNECT_IPV6
     s_semph_get_ip6_addrs = xSemaphoreCreateBinary();
     if (s_semph_get_ip6_addrs == NULL) {
@@ -227,7 +229,9 @@ esp_err_t example_ethernet_connect(void)
 #endif
     eth_start();
     ESP_LOGI(TAG, "Waiting for IP(s).");
+#if CONFIG_EXAMPLE_CONNECT_IPV4
     xSemaphoreTake(s_semph_get_ip_addrs, portMAX_DELAY);
+#endif
 #if CONFIG_EXAMPLE_CONNECT_IPV6
     xSemaphoreTake(s_semph_get_ip6_addrs, portMAX_DELAY);
 #endif

examples/common_components/protocol_examples_common/wifi_connect.c

@@ -1,5 +1,5 @@
 /*
- * SPDX-FileCopyrightText: 2022 Espressif Systems (Shanghai) CO LTD
+ * SPDX-FileCopyrightText: 2022-2023 Espressif Systems (Shanghai) CO LTD
  *
  * SPDX-License-Identifier: Unlicense OR CC0-1.0
  */
@@ -196,7 +196,9 @@ esp_err_t example_wifi_sta_do_connect(wifi_config_t wifi_config, bool wait)
     }
     if (wait) {
         ESP_LOGI(TAG, "Waiting for IP(s)");
+#if CONFIG_EXAMPLE_CONNECT_IPV4
         xSemaphoreTake(s_semph_get_ip_addrs, portMAX_DELAY);
+#endif
 #if CONFIG_EXAMPLE_CONNECT_IPV6
         xSemaphoreTake(s_semph_get_ip6_addrs, portMAX_DELAY);
 #endif