Change: use TCP for everything except for master-server and initial server scan (#9130)

This means that pressing Refresh button and adding servers manually
now uses TCP.

The master-server and initial scan are still UDP as they will be
replaced by Game Coordinator; no need to change this now.

If we query a server that is too old, show a proper warning to the
user informing him the server is too old.

8 files changed, 78 insertions, 43 deletions

diff --git a/os/emscripten/pre.js b/os/emscripten/pre.js
index 1563e4f95..82664004e 100644
--- a/os/emscripten/pre.js
+++ b/os/emscripten/pre.js
@@ -65,10 +65,14 @@ Module.preRun.push(function() {
     }
 
     window.openttd_server_list = function() {
-        add_server = Module.cwrap("em_openttd_add_server", null, ["string", "number"]);
+        add_server = Module.cwrap("em_openttd_add_server", null, ["string"]);
 
-        /* Add servers that support WebSocket here. Example:
-         *  add_server("localhost", 3979); */
+        /* Add servers that support WebSocket here. Examples:
+         *  add_server("localhost");
+         *  add_server("localhost:3979");
+         *  add_server("127.0.0.1:3979");
+         *  add_server("[::1]:3979");
+         */
     }
 
     var leftButtonDown = false;
diff --git a/src/lang/english.txt b/src/lang/english.txt
index 3037bf90f..f8e3618e5 100644
--- a/src/lang/english.txt
+++ b/src/lang/english.txt
@@ -2217,6 +2217,7 @@ STR_NETWORK_ERROR_TIMEOUT_COMPUTER                              :{WHITE}Your com
 STR_NETWORK_ERROR_TIMEOUT_MAP                                   :{WHITE}Your computer took too long to download the map
 STR_NETWORK_ERROR_TIMEOUT_JOIN                                  :{WHITE}Your computer took too long to join the server
 STR_NETWORK_ERROR_INVALID_CLIENT_NAME                           :{WHITE}Your player name is not valid
+STR_NETWORK_ERROR_SERVER_TOO_OLD                                :{WHITE}The queried server is too old for this client
 
 ############ Leave those lines in this order!!
 STR_NETWORK_ERROR_CLIENT_GENERAL                                :general error
diff --git a/src/network/network.cpp b/src/network/network.cpp
index d7cf9367a..c31a67487 100644
--- a/src/network/network.cpp
+++ b/src/network/network.cpp
@@ -602,8 +602,11 @@ static void NetworkInitialize(bool close_admins = true)
 
 /** Non blocking connection create to query servers */
 class TCPQueryConnecter : TCPConnecter {
+private:
+	bool request_company_info;
+
 public:
-	TCPQueryConnecter(const NetworkAddress &address) : TCPConnecter(address) {}
+	TCPQueryConnecter(const NetworkAddress &address, bool request_company_info) : TCPConnecter(address), request_company_info(request_company_info) {}
 
 	void OnFailure() override
 	{
@@ -613,36 +616,53 @@ public:
 	void OnConnect(SOCKET s) override
 	{
 		_networking = true;
-		new ClientNetworkGameSocketHandler(s);
-		MyClient::SendInformationQuery();
+		new ClientNetworkGameSocketHandler(s, address);
+		MyClient::SendInformationQuery(request_company_info);
 	}
 };
 
 /**
  * Query a server to fetch his game-info.
  * @param address the address to query.
+ * @param request_company_info Whether to request company info too.
  */
-void NetworkTCPQueryServer(NetworkAddress address)
+void NetworkTCPQueryServer(NetworkAddress address, bool request_company_info)
 {
 	if (!_network_available) return;
 
 	NetworkDisconnect();
 	NetworkInitialize();
 
-	new TCPQueryConnecter(address);
+	new TCPQueryConnecter(address, request_company_info);
 }
 
 /**
  * Validates an address entered as a string and adds the server to
  * the list. If you use this function, the games will be marked
  * as manually added.
- * @param connection_string The IP:port to add to the list.
+ * @param connection_string The IP:port of the server to add.
+ * @return The entry on the game list.
  */
-void NetworkAddServer(const char *connection_string)
+NetworkGameList *NetworkAddServer(const std::string &connection_string)
 {
-	if (StrEmpty(connection_string)) return;
+	if (connection_string.empty()) return nullptr;
+
+	NetworkAddress address = ParseConnectionString(connection_string, NETWORK_DEFAULT_PORT);
+
+	/* Ensure the item already exists in the list */
+	NetworkGameList *item = NetworkGameListAddItem(address);
+	if (StrEmpty(item->info.server_name)) {
+		ClearGRFConfigList(&item->info.grfconfig);
+		address.GetAddressAsString(item->info.server_name, lastof(item->info.server_name));
+		item->manually = true;
+
+		NetworkRebuildHostList();
+		UpdateNetworkGameWindow();
+	}
+
+	NetworkTCPQueryServer(address);
 
-	NetworkUDPQueryServer(ParseConnectionString(connection_string, NETWORK_DEFAULT_PORT), true);
+	return item;
 }
 
 /**
@@ -687,7 +707,7 @@ public:
 	void OnConnect(SOCKET s) override
 	{
 		_networking = true;
-		new ClientNetworkGameSocketHandler(s);
+		new ClientNetworkGameSocketHandler(s, this->address);
 		IConsoleCmdExec("exec scripts/on_client.scr 0");
 		NetworkClient_Connected();
 	}
@@ -1132,9 +1152,9 @@ void NetworkShutDown()
 #ifdef __EMSCRIPTEN__
 extern "C" {
 
-void CDECL em_openttd_add_server(const char *host, int port)
+void CDECL em_openttd_add_server(const char *connection_string)
 {
-	NetworkUDPQueryServer(NetworkAddress(host, port), true);
+	NetworkAddServer(connection_string);
 }
 
 }
diff --git a/src/network/network_client.cpp b/src/network/network_client.cpp
index af7073e55..f73c8be52 100644
--- a/src/network/network_client.cpp
+++ b/src/network/network_client.cpp
@@ -145,7 +145,7 @@ void ClientNetworkEmergencySave()
  * Create a new socket for the client side of the game connection.
  * @param s The socket to connect with.
  */
-ClientNetworkGameSocketHandler::ClientNetworkGameSocketHandler(SOCKET s) : NetworkGameSocketHandler(s), savegame(nullptr), status(STATUS_INACTIVE)
+ClientNetworkGameSocketHandler::ClientNetworkGameSocketHandler(SOCKET s, NetworkAddress address) : NetworkGameSocketHandler(s), address(address), savegame(nullptr), status(STATUS_INACTIVE)
 {
 	assert(ClientNetworkGameSocketHandler::my_client == nullptr);
 	ClientNetworkGameSocketHandler::my_client = this;
@@ -345,14 +345,18 @@ static_assert(NETWORK_SERVER_ID_LENGTH == 16 * 2 + 1);
 /**
  * Query the server for server information.
  */
-NetworkRecvStatus ClientNetworkGameSocketHandler::SendInformationQuery()
+NetworkRecvStatus ClientNetworkGameSocketHandler::SendInformationQuery(bool request_company_info)
 {
-	my_client->status = STATUS_COMPANY_INFO;
-	_network_join_status = NETWORK_JOIN_STATUS_GETTING_COMPANY_INFO;
-	SetWindowDirty(WC_NETWORK_STATUS_WINDOW, WN_NETWORK_STATUS_WINDOW_JOIN);
-
+	my_client->status = STATUS_GAME_INFO;
 	my_client->SendPacket(new Packet(PACKET_CLIENT_GAME_INFO));
-	my_client->SendPacket(new Packet(PACKET_CLIENT_COMPANY_INFO));
+
+	if (request_company_info) {
+		my_client->status = STATUS_COMPANY_INFO;
+		_network_join_status = NETWORK_JOIN_STATUS_GETTING_COMPANY_INFO;
+		SetWindowDirty(WC_NETWORK_STATUS_WINDOW, WN_NETWORK_STATUS_WINDOW_JOIN);
+
+		my_client->SendPacket(new Packet(PACKET_CLIENT_COMPANY_INFO));
+	}
 
 	return NETWORK_RECV_STATUS_OKAY;
 }
@@ -577,9 +581,13 @@ NetworkRecvStatus ClientNetworkGameSocketHandler::Receive_SERVER_BANNED(Packet *
 
 NetworkRecvStatus ClientNetworkGameSocketHandler::Receive_SERVER_GAME_INFO(Packet *p)
 {
-	if (this->status != STATUS_COMPANY_INFO && this->status != STATUS_INACTIVE) return NETWORK_RECV_STATUS_MALFORMED_PACKET;
+	if (this->status != STATUS_COMPANY_INFO && this->status != STATUS_GAME_INFO) return NETWORK_RECV_STATUS_MALFORMED_PACKET;
 
 	NetworkGameList *item = GetLobbyGameInfo();
+	if (item == nullptr) {
+		/* This is not the lobby, so add it to the game list. */
+		item = NetworkGameListAddItem(this->address);
+	}
 
 	/* Clear any existing GRFConfig chain. */
 	ClearGRFConfigList(&item->info.grfconfig);
@@ -590,6 +598,8 @@ NetworkRecvStatus ClientNetworkGameSocketHandler::Receive_SERVER_GAME_INFO(Packe
 	/* Ensure we consider the server online. */
 	item->online = true;
 
+	/* It could be either window, but only one is open, so redraw both. */
+	SetWindowDirty(WC_NETWORK_WINDOW, WN_NETWORK_WINDOW_GAME);
 	SetWindowDirty(WC_NETWORK_WINDOW, WN_NETWORK_WINDOW_LOBBY);
 
 	/* We will receive company info next, so keep connection open. */
@@ -727,6 +737,15 @@ NetworkRecvStatus ClientNetworkGameSocketHandler::Receive_SERVER_ERROR(Packet *p
 
 	NetworkErrorCode error = (NetworkErrorCode)p->Recv_uint8();
 
+	/* If we query a server that is 1.11.1 or older, we get an
+	 * NETWORK_ERROR_NOT_EXPECTED on requesting the game info. Show a special
+	 * error popup in that case.
+	 */
+	if (error == NETWORK_ERROR_NOT_EXPECTED && (this->status == STATUS_GAME_INFO || this->status == STATUS_COMPANY_INFO)) {
+		ShowErrorMessage(STR_NETWORK_ERROR_SERVER_TOO_OLD, INVALID_STRING_ID, WL_CRITICAL);
+		return NETWORK_RECV_STATUS_CLOSE_QUERY;
+	}
+
 	StringID err = STR_NETWORK_ERROR_LOSTCONNECTION;
 	if (error < (ptrdiff_t)lengthof(network_error_strings)) err = network_error_strings[error];
 	/* In case of kicking a client, we assume there is a kick message in the packet if we can read one byte */
diff --git a/src/network/network_client.h b/src/network/network_client.h
index 66cdb8ba5..40b8eedf9 100644
--- a/src/network/network_client.h
+++ b/src/network/network_client.h
@@ -15,12 +15,14 @@
 /** Class for handling the client side of the game connection. */
 class ClientNetworkGameSocketHandler : public ZeroedMemoryAllocator, public NetworkGameSocketHandler {
 private:
+	NetworkAddress address;        ///< Address we are connected to.
 	struct PacketReader *savegame; ///< Packet reader for reading the savegame.
 	byte token;                    ///< The token we need to send back to the server to prove we're the right client.
 
 	/** Status of the connection with the server. */
 	enum ServerStatus {
 		STATUS_INACTIVE,      ///< The client is not connected nor active.
+		STATUS_GAME_INFO,     ///< We are trying to get the game information.
 		STATUS_COMPANY_INFO,  ///< We are trying to get company information.
 		STATUS_JOIN,          ///< We are trying to join a server.
 		STATUS_NEWGRFS_CHECK, ///< Last action was checking NewGRFs.
@@ -74,13 +76,13 @@ protected:
 	static NetworkRecvStatus SendMapOk();
 	void CheckConnection();
 public:
-	ClientNetworkGameSocketHandler(SOCKET s);
+	ClientNetworkGameSocketHandler(SOCKET s, NetworkAddress address);
 	~ClientNetworkGameSocketHandler();
 
 	NetworkRecvStatus CloseConnection(NetworkRecvStatus status) override;
 	void ClientError(NetworkRecvStatus res);
 
-	static NetworkRecvStatus SendInformationQuery();
+	static NetworkRecvStatus SendInformationQuery(bool request_company_info);
 
 	static NetworkRecvStatus SendJoin();
 	static NetworkRecvStatus SendCommand(const CommandPacket *cp);
diff --git a/src/network/network_gamelist.cpp b/src/network/network_gamelist.cpp
index 6d4285c85..12dbbce61 100644
--- a/src/network/network_gamelist.cpp
+++ b/src/network/network_gamelist.cpp
@@ -69,15 +69,6 @@ static void NetworkGameListHandleDelayedInsert()
  */
 NetworkGameList *NetworkGameListAddItem(NetworkAddress address)
 {
-	const char *hostname = address.GetHostname();
-
-	/* Do not query the 'any' address. */
-	if (StrEmpty(hostname) ||
-			strcmp(hostname, "0.0.0.0") == 0 ||
-			strcmp(hostname, "::") == 0) {
-		return nullptr;
-	}
-
 	NetworkGameList *item, *prev_item;
 
 	prev_item = nullptr;
@@ -95,7 +86,6 @@ NetworkGameList *NetworkGameListAddItem(NetworkAddress address)
 	} else {
 		prev_item->next = item;
 	}
-	DEBUG(net, 4, "[gamelist] added server to list");
 
 	UpdateNetworkGameWindow();
 
diff --git a/src/network/network_gui.cpp b/src/network/network_gui.cpp
index 3204b2b96..590f2f5e0 100644
--- a/src/network/network_gui.cpp
+++ b/src/network/network_gui.cpp
@@ -472,9 +472,8 @@ public:
 		EM_ASM(if (window["openttd_server_list"]) openttd_server_list());
 #endif
 
-		this->last_joined = NetworkGameListAddItem(ParseConnectionString(_settings_client.network.last_joined, NETWORK_DEFAULT_PORT));
+		this->last_joined = NetworkAddServer(_settings_client.network.last_joined);
 		this->server = this->last_joined;
-		if (this->last_joined != nullptr) NetworkUDPQueryServer(this->last_joined->address);
 
 		this->requery_timer.SetInterval(MILLISECONDS_PER_TICK);
 
@@ -750,7 +749,7 @@ public:
 				break;
 
 			case WID_NG_REFRESH: // Refresh
-				if (this->server != nullptr) NetworkUDPQueryServer(this->server->address);
+				if (this->server != nullptr) NetworkTCPQueryServer(this->server->address);
 				break;
 
 			case WID_NG_NEWGRF: // NewGRF Settings
@@ -971,7 +970,7 @@ void ShowNetworkGameWindow()
 		first = false;
 		/* Add all servers from the config file to our list. */
 		for (const auto &iter : _network_host_list) {
-			NetworkAddServer(iter.c_str());
+			NetworkAddServer(iter);
 		}
 	}
 
@@ -1485,7 +1484,7 @@ struct NetworkLobbyWindow : public Window {
 				/* Clear the information so removed companies don't remain */
 				for (auto &company : this->company_info) company = {};
 
-				NetworkTCPQueryServer(this->server->address);
+				NetworkTCPQueryServer(this->server->address, true);
 				break;
 		}
 	}
@@ -1555,7 +1554,7 @@ static void ShowNetworkLobbyWindow(NetworkGameList *ngl)
 
 	strecpy(_settings_client.network.last_joined, ngl->address.GetAddressAsString(false).c_str(), lastof(_settings_client.network.last_joined));
 
-	NetworkTCPQueryServer(ngl->address);
+	NetworkTCPQueryServer(ngl->address, true);
 
 	new NetworkLobbyWindow(&_network_lobby_window_desc, ngl);
 }
diff --git a/src/network/network_internal.h b/src/network/network_internal.h
index ff3c8c22d..683c954e8 100644
--- a/src/network/network_internal.h
+++ b/src/network/network_internal.h
@@ -87,10 +87,10 @@ extern uint8 _network_reconnect;
 
 extern CompanyMask _network_company_passworded;
 
-void NetworkTCPQueryServer(NetworkAddress address);
+void NetworkTCPQueryServer(NetworkAddress address, bool request_company_info = false);
 
 void GetBindAddresses(NetworkAddressList *addresses, uint16 port);
-void NetworkAddServer(const char *b);
+struct NetworkGameList *NetworkAddServer(const std::string &connection_string);
 void NetworkRebuildHostList();
 void UpdateNetworkGameWindow();