feat(Core): replace ACE network with Boost.Asio (#6574)

src/server/shared/Realms/Realm.cpp

@@ -0,0 +1,44 @@
+/*
+ * Copyright (C) 2016+ AzerothCore <www.azerothcore.org>, released under GNU AGPL v3 license: https://github.com/azerothcore/azerothcore-wotlk/blob/master/LICENSE-AGPL3
+ * Copyright (C) 2021+ WarheadCore <https://github.com/WarheadCore>
+ */
+
+#include "Realm.h"
+#include "IpAddress.h"
+#include "IpNetwork.h"
+#include <boost/asio/ip/tcp.hpp>
+
+boost::asio::ip::tcp_endpoint Realm::GetAddressForClient(boost::asio::ip::address const& clientAddr) const
+{
+    boost::asio::ip::address realmIp;
+
+    // Attempt to send best address for client
+    if (clientAddr.is_loopback())
+    {
+        // Try guessing if realm is also connected locally
+        if (LocalAddress->is_loopback() || ExternalAddress->is_loopback())
+        {
+            realmIp = clientAddr;
+        }
+        else
+        {
+            // Assume that user connecting from the machine that bnetserver is located on
+            // has all realms available in his local network
+            realmIp = *LocalAddress;
+        }
+    }
+    else
+    {
+        if (clientAddr.is_v4() && Acore::Net::IsInNetwork(LocalAddress->to_v4(), LocalSubnetMask->to_v4(), clientAddr.to_v4()))
+        {
+            realmIp = *LocalAddress;
+        }
+        else
+        {
+            realmIp = *ExternalAddress;
+        }
+    }
+
+    // Return external IP
+    return boost::asio::ip::tcp_endpoint(realmIp, Port);
+}