feat(lwip): Added wrapper for getaddrinfo to handle AF_UNSPEC

components/lwip/include/apps/esp_netdb.h

@@ -0,0 +1,39 @@
+/*
+ * SPDX-FileCopyrightText: 2015-2024 Espressif Systems (Shanghai) CO LTD
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+#ifndef __ESP_NETDB_H__
+#define __ESP_NETDB_H__
+
+#include "sdkconfig.h"
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/**
+ * @brief Custom getaddrinfo() wrapper for lwIP that handles AF_UNSPEC correctly.
+ *
+ * Resolves both IPv4 and IPv6 addresses when AF_UNSPEC is specified. Works
+ * even if only one protocol (IPv4 or IPv6) is enabled in lwIP. Merges results
+ * if both protocols are available.
+ *
+ * @return 0 on success, or an error code on failure.
+ *         - `EAI_FAMILY`: Address family not supported.
+ *
+ * @note Caller must free the result list with freeaddrinfo().
+ *
+ * @see getaddrinfo(), freeaddrinfo()
+ */
+#if CONFIG_LWIP_USE_ESP_GETADDRINFO
+int esp_getaddrinfo(const char *nodename, const char *servname,
+                        const struct addrinfo *hints, struct addrinfo **res);
+#endif
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif // __ESP_NETDB_H__