Fix: "Search LAN games" used the socket after it was closed (#9437)

Every outgoing connection, either TCP or UDP, triggered
NetworkInitialize(), which triggered NetworkUDPInitialize() which
first closes all connections.

Now the problem was that "Search LAN games" found a server, added
it to the list, after which (over TCP) it queries the server. This
closes all UDP sockets (as that makes sense, I guess?), while the
UDP was still reading from it.

Solve this by simply stop initializing UDP every time we make an
outgoing TCP connection; instead only do it on start-up.

1 files changed, 2 insertions, 1 deletions

diff --git a/src/network/network.cpp b/src/network/network.cpp
index d35fbe746..d5d6d8282 100644
--- a/src/network/network.cpp
+++ b/src/network/network.cpp
@@ -615,7 +615,6 @@ void NetworkClose(bool close_admins)
 static void NetworkInitialize(bool close_admins = true)
 {
 	InitializeNetworkPools(close_admins);
-	NetworkUDPInitialize();
 
 	_sync_frame = 0;
 	_network_first_time = true;
@@ -907,6 +906,7 @@ bool NetworkServerStart()
 
 	NetworkDisconnect(false, false);
 	NetworkInitialize(false);
+	NetworkUDPInitialize();
 	Debug(net, 5, "Starting listeners for clients");
 	if (!ServerNetworkGameSocketHandler::Listen(_settings_client.network.server_port)) return false;
 
@@ -1292,6 +1292,7 @@ void NetworkStartUp()
 	_network_game_info = {};
 
 	NetworkInitialize();
+	NetworkUDPInitialize();
 	Debug(net, 3, "Network online, multiplayer available");
 	NetworkFindBroadcastIPs(&_broadcast_list);
 }