From fc4bf4e98359ebcc593f71688157be035238aedf Mon Sep 17 00:00:00 2001
From: lganzzzo <lganzzzo@gmail.com>
Date: Mon, 17 Jan 2022 02:11:16 +0200
Subject: [PATCH] tcp::server::ConnectionProvider: Fix dual-stack sockets on
 Windows (#549).

---
 src/oatpp/network/tcp/server/ConnectionProvider.cpp | 10 ++++++++++
 1 file changed, 10 insertions(+)

diff --git a/src/oatpp/network/tcp/server/ConnectionProvider.cpp b/src/oatpp/network/tcp/server/ConnectionProvider.cpp
index 0fbc5fa1..adc07396 100644
--- a/src/oatpp/network/tcp/server/ConnectionProvider.cpp
+++ b/src/oatpp/network/tcp/server/ConnectionProvider.cpp
@@ -184,6 +184,16 @@ oatpp::v_io_handle ConnectionProvider::instantiateServer(){
 
     if (serverHandle != INVALID_SOCKET) {
 
+      int no = 0;
+
+      if (hints.ai_family == AF_UNSPEC || hints.ai_family == Address::IP_6) {
+        if (setsockopt(serverHandle, IPPROTO_IPV6, IPV6_V6ONLY, (char*)&no, sizeof( int ) ) != 0 ) {
+          OATPP_LOGW("[oatpp::network::tcp::server::ConnectionProvider::instantiateServer()]",
+                     "Warning. Failed to set %s for accepting socket: %s", "IPV6_V6ONLY",
+                     strerror(errno));
+        }
+      }
+
       if (bind(serverHandle, currResult->ai_addr, (int) currResult->ai_addrlen) != SOCKET_ERROR &&
           listen(serverHandle, SOMAXCONN) != SOCKET_ERROR)
       {