(svn r20938) -Codechange: make the code for listening on a socket (more) reusable

4 files changed, 236 insertions, 144 deletions

diff --git a/src/network/core/tcp_listen.h b/src/network/core/tcp_listen.h
new file mode 100644
index 000000000..800f81219
--- /dev/null
+++ b/src/network/core/tcp_listen.h
@@ -0,0 +1,178 @@
+/* $Id: tcp.h 20933 2010-10-15 19:33:08Z rubidium $ */
+
+/*
+ * This file is part of OpenTTD.
+ * OpenTTD is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, version 2.
+ * OpenTTD is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ * See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with OpenTTD. If not, see <http://www.gnu.org/licenses/>.
+ */
+
+/**
+ * @file tcp.h Basic functions to listen for TCP connections.
+ */
+
+#ifndef NETWORK_CORE_TCP_LISTEN_H
+#define NETWORK_CORE_TCP_LISTEN_H
+
+#include "tcp.h"
+#include "../network.h"
+#include "../../core/pool_type.hpp"
+#include "../../debug.h"
+#include "table/strings.h"
+
+#ifdef ENABLE_NETWORK
+
+/**
+ * Template for TCP listeners.
+ * @param Tsocket      The class we create sockets for.
+ * @param Tfull_packet The packet type to return when we don't allow more sockets.
+ * @param Tban_packet  The packet type to return when the client is banned.
+ */
+template <class Tsocket, PacketType Tfull_packet, PacketType Tban_packet>
+class TCPListenHandler {
+	/** List of sockets we listen on. */
+	static SocketList sockets;
+
+public:
+	/**
+	 * Accepts clients from the sockets.
+	 * @param ls Socket to accept clients from.
+	 */
+	static void AcceptClient(SOCKET ls)
+	{
+		for (;;) {
+			struct sockaddr_storage sin;
+			memset(&sin, 0, sizeof(sin));
+			socklen_t sin_len = sizeof(sin);
+			SOCKET s = accept(ls, (struct sockaddr*)&sin, &sin_len);
+			if (s == INVALID_SOCKET) return;
+
+			SetNonBlocking(s); // XXX error handling?
+
+			NetworkAddress address(sin, sin_len);
+			DEBUG(net, 1, "[%s] Client connected from %s on frame %d", Tsocket::GetName(), address.GetHostname(), _frame_counter);
+
+			SetNoDelay(s); // XXX error handling?
+
+			/* Check if the client is banned */
+			bool banned = false;
+			for (char **iter = _network_ban_list.Begin(); iter != _network_ban_list.End(); iter++) {
+				banned = address.IsInNetmask(*iter);
+				if (banned) {
+					Packet p(Tban_packet);
+					p.PrepareToSend();
+
+					DEBUG(net, 1, "[%s] Banned ip tried to join (%s), refused", Tsocket::GetName(), *iter);
+
+					send(s, (const char*)p.buffer, p.size, 0);
+					closesocket(s);
+					break;
+				}
+			}
+			/* If this client is banned, continue with next client */
+			if (banned) continue;
+
+			/* Can we handle a new client? */
+			if (!Tsocket::AllowConnection()) {
+				/* no more clients allowed?
+				* Send to the client that we are full! */
+				Packet p(Tfull_packet);
+				p.PrepareToSend();
+
+				send(s, (const char*)p.buffer, p.size, 0);
+				closesocket(s);
+
+				continue;
+			}
+
+			Tsocket::AcceptConnection(s, address);
+		}
+	}
+
+	/**
+	 * Handle the receiving of packets.
+	 * @return true if everything went okay.
+	 */
+	static bool Receive()
+	{
+		fd_set read_fd, write_fd;
+		struct timeval tv;
+
+		FD_ZERO(&read_fd);
+		FD_ZERO(&write_fd);
+
+
+		Tsocket *cs;
+		FOR_ALL_ITEMS_FROM(Tsocket, idx, cs, 0) {
+			FD_SET(cs->sock, &read_fd);
+			FD_SET(cs->sock, &write_fd);
+		}
+
+		/* take care of listener port */
+		for (SocketList::iterator s = sockets.Begin(); s != sockets.End(); s++) {
+			FD_SET(s->second, &read_fd);
+		}
+
+		tv.tv_sec = tv.tv_usec = 0; // don't block at all.
+#if !defined(__MORPHOS__) && !defined(__AMIGA__)
+		select(FD_SETSIZE, &read_fd, &write_fd, NULL, &tv);
+#else
+		WaitSelect(FD_SETSIZE, &read_fd, &write_fd, NULL, &tv, NULL);
+#endif
+
+		/* accept clients.. */
+		for (SocketList::iterator s = sockets.Begin(); s != sockets.End(); s++) {
+			if (FD_ISSET(s->second, &read_fd)) AcceptClient(s->second);
+		}
+
+		/* read stuff from clients */
+		FOR_ALL_ITEMS_FROM(Tsocket, idx, cs, 0) {
+			cs->writable = !!FD_ISSET(cs->sock, &write_fd);
+			if (FD_ISSET(cs->sock, &read_fd)) {
+				cs->Recv_Packets();
+			}
+		}
+		return _networking;
+	}
+
+	/**
+	 * Listen on a particular port.
+	 * @param port The port to listen on.
+	 * @return true if listening succeeded.
+	 */
+	static bool Listen(uint16 port)
+	{
+		assert(sockets.Length() == 0);
+
+		NetworkAddressList addresses;
+		GetBindAddresses(&addresses, port);
+
+		for (NetworkAddress *address = addresses.Begin(); address != addresses.End(); address++) {
+			address->Listen(SOCK_STREAM, &sockets);
+		}
+
+		if (sockets.Length() == 0) {
+			DEBUG(net, 0, "[server] could not start network: could not create listening socket");
+			NetworkError(STR_NETWORK_ERROR_SERVER_START);
+			return false;
+		}
+
+		return true;
+	}
+
+	/** Close the sockets we're listening on. */
+	static void CloseListeners()
+	{
+		for (SocketList::iterator s = sockets.Begin(); s != sockets.End(); s++) {
+			closesocket(s->second);
+		}
+		sockets.Clear();
+		DEBUG(net, 1, "[%s] closed listeners", Tsocket::GetName());
+	}
+};
+
+template <class Tsocket, PacketType Tfull_packet, PacketType Tban_packet> SocketList TCPListenHandler<Tsocket, Tfull_packet, Tban_packet>::sockets;
+
+#endif /* ENABLE_NETWORK */
+
+#endif /* NETWORK_CORE_TCP_LISTEN_H */
diff --git a/src/network/network.cpp b/src/network/network.cpp
index 435a8eb91..309a9f025 100644
--- a/src/network/network.cpp
+++ b/src/network/network.cpp
@@ -87,9 +87,6 @@ extern NetworkUDPSocketHandler *_udp_client_socket; ///< udp client socket
 extern NetworkUDPSocketHandler *_udp_server_socket; ///< udp server socket
 extern NetworkUDPSocketHandler *_udp_master_socket; ///< udp master socket
 
-/* The listen socket for the server */
-static SocketList _listensockets;
-
 /* The amount of clients connected */
 byte _network_clients_connected = 0;
 
@@ -234,12 +231,6 @@ void NetworkError(StringID error_string)
 	_switch_mode_errorstr = error_string;
 }
 
-static void ServerStartError(const char *error)
-{
-	DEBUG(net, 0, "[server] could not start network: %s",error);
-	NetworkError(STR_NETWORK_ERROR_SERVER_START);
-}
-
 /**
  * Retrieve the string id of an internal error number
  * @param err NetworkErrorCode
@@ -428,82 +419,14 @@ void ParseConnectionString(const char **company, const char **port, char *connec
 	}
 }
 
-/* For the server, to accept new clients */
-static void NetworkAcceptClients(SOCKET ls)
+/* static */ void ServerNetworkGameSocketHandler::AcceptConnection(SOCKET s, const NetworkAddress &address)
 {
-	for (;;) {
-		struct sockaddr_storage sin;
-		memset(&sin, 0, sizeof(sin));
-		socklen_t sin_len = sizeof(sin);
-		SOCKET s = accept(ls, (struct sockaddr*)&sin, &sin_len);
-		if (s == INVALID_SOCKET) return;
-
-		SetNonBlocking(s); // XXX error handling?
-
-		NetworkAddress address(sin, sin_len);
-		DEBUG(net, 1, "Client connected from %s on frame %d", address.GetHostname(), _frame_counter);
-
-		SetNoDelay(s); // XXX error handling?
-
-		/* Check if the client is banned */
-		bool banned = false;
-		for (char **iter = _network_ban_list.Begin(); iter != _network_ban_list.End(); iter++) {
-			banned = address.IsInNetmask(*iter);
-			if (banned) {
-				Packet p(PACKET_SERVER_BANNED);
-				p.PrepareToSend();
-
-				DEBUG(net, 1, "Banned ip tried to join (%s), refused", *iter);
-
-				send(s, (const char*)p.buffer, p.size, 0);
-				closesocket(s);
-				break;
-			}
-		}
-		/* If this client is banned, continue with next client */
-		if (banned) continue;
-
-		/* Can we handle a new client? */
-		if (_network_clients_connected >= MAX_CLIENTS ||
-				_network_game_info.clients_on >= _settings_client.network.max_clients) {
-			/* no more clients allowed?
-			 * Send to the client that we are full! */
-			Packet p(PACKET_SERVER_FULL);
-			p.PrepareToSend();
-
-			send(s, (const char*)p.buffer, p.size, 0);
-			closesocket(s);
+	/* Register the login */
+	_network_clients_connected++;
 
-			continue;
-		}
-
-		/* Register the login */
-		_network_clients_connected++;
-
-		SetWindowDirty(WC_CLIENT_LIST, 0);
-		ServerNetworkGameSocketHandler *cs = new ServerNetworkGameSocketHandler(s);
-		cs->GetInfo()->client_address = address; // Save the IP of the client
-	}
-}
-
-/* Set up the listen socket for the server */
-static bool NetworkListen()
-{
-	assert(_listensockets.Length() == 0);
-
-	NetworkAddressList addresses;
-	GetBindAddresses(&addresses, _settings_client.network.server_port);
-
-	for (NetworkAddress *address = addresses.Begin(); address != addresses.End(); address++) {
-		address->Listen(SOCK_STREAM, &_listensockets);
-	}
-
-	if (_listensockets.Length() == 0) {
-		ServerStartError("Could not create listening socket");
-		return false;
-	}
-
-	return true;
+	SetWindowDirty(WC_CLIENT_LIST, 0);
+	ServerNetworkGameSocketHandler *cs = new ServerNetworkGameSocketHandler(s);
+	cs->GetInfo()->client_address = address; // Save the IP of the client
 }
 
 /** Resets both pools used for network clients */
@@ -521,12 +444,7 @@ void NetworkClose()
 		FOR_ALL_CLIENT_SOCKETS(cs) {
 			cs->CloseConnection(NETWORK_RECV_STATUS_CONN_LOST);
 		}
-		/* We are a server, also close the listensocket */
-		for (SocketList::iterator s = _listensockets.Begin(); s != _listensockets.End(); s++) {
-			closesocket(s->second);
-		}
-		_listensockets.Clear();
-		DEBUG(net, 1, "[tcp] closed listeners");
+		ServerNetworkGameSocketHandler::CloseListeners();
 	} else if (MyClient::my_client != NULL) {
 		MyClient::SendQuit();
 		MyClient::my_client->Send_Packets();
@@ -713,7 +631,7 @@ bool NetworkServerStart()
 
 	NetworkDisconnect();
 	NetworkInitialize();
-	if (!NetworkListen()) return false;
+	if (!ServerNetworkGameSocketHandler::Listen(_settings_client.network.server_port)) return false;
 
 	/* Try to start UDP-server */
 	_network_udp_server = _udp_server_socket->Listen();
@@ -789,67 +707,20 @@ void NetworkDisconnect(bool blocking)
  */
 static bool NetworkReceive()
 {
-	if (!_network_server) {
+	if (_network_server) {
+		return ServerNetworkGameSocketHandler::Receive();
+	} else {
 		return ClientNetworkGameSocketHandler::Receive();
 	}
-	NetworkClientSocket *cs;
-	fd_set read_fd, write_fd;
-	struct timeval tv;
-
-	FD_ZERO(&read_fd);
-	FD_ZERO(&write_fd);
-
-	FOR_ALL_CLIENT_SOCKETS(cs) {
-		FD_SET(cs->sock, &read_fd);
-		FD_SET(cs->sock, &write_fd);
-	}
-
-	/* take care of listener port */
-	for (SocketList::iterator s = _listensockets.Begin(); s != _listensockets.End(); s++) {
-		FD_SET(s->second, &read_fd);
-	}
-
-	tv.tv_sec = tv.tv_usec = 0; // don't block at all.
-#if !defined(__MORPHOS__) && !defined(__AMIGA__)
-	int n = select(FD_SETSIZE, &read_fd, &write_fd, NULL, &tv);
-#else
-	int n = WaitSelect(FD_SETSIZE, &read_fd, &write_fd, NULL, &tv, NULL);
-#endif
-	if (n == -1 && !_network_server) NetworkError(STR_NETWORK_ERROR_LOSTCONNECTION);
-
-	/* accept clients.. */
-	for (SocketList::iterator s = _listensockets.Begin(); s != _listensockets.End(); s++) {
-		if (FD_ISSET(s->second, &read_fd)) NetworkAcceptClients(s->second);
-	}
-
-	/* read stuff from clients */
-	FOR_ALL_CLIENT_SOCKETS(cs) {
-		cs->writable = !!FD_ISSET(cs->sock, &write_fd);
-		if (FD_ISSET(cs->sock, &read_fd)) {
-			cs->Recv_Packets();
-		}
-	}
-	return _networking;
 }
 
 /* This sends all buffered commands (if possible) */
 static void NetworkSend()
 {
-	if (!_network_server) {
+	if (_network_server) {
+		ServerNetworkGameSocketHandler::Send();
+	} else {
 		ClientNetworkGameSocketHandler::Send();
-		return;
-	}
-
-	NetworkClientSocket *cs;
-	FOR_ALL_CLIENT_SOCKETS(cs) {
-		if (cs->writable) {
-			cs->Send_Packets();
-
-			if (cs->status == STATUS_MAP) {
-				/* This client is in the middle of a map-send, call the function for that */
-				cs->SendMap();
-			}
-		}
 	}
 }
 
diff --git a/src/network/network_server.cpp b/src/network/network_server.cpp
index ccb1bb37e..ab2bd1632 100644
--- a/src/network/network_server.cpp
+++ b/src/network/network_server.cpp
@@ -49,6 +49,9 @@ assert_compile(NetworkClientSocketPool::MAX_SIZE == MAX_CLIENT_SLOTS);
 NetworkClientSocketPool _networkclientsocket_pool("NetworkClientSocket");
 INSTANTIATE_POOL_METHODS(NetworkClientSocket)
 
+/** Instantiate the listen sockets. */
+template SocketList TCPListenHandler<ServerNetworkGameSocketHandler, PACKET_SERVER_FULL, PACKET_SERVER_BANNED>::sockets;
+
 /**
  * Create a new socket for the server side of the game connection.
  * @param s The socket to connect with.
@@ -118,6 +121,32 @@ NetworkRecvStatus ServerNetworkGameSocketHandler::CloseConnection(NetworkRecvSta
 	return status;
 }
 
+/**
+ * Whether an connection is allowed or not at this moment.
+ * @return true if the connection is allowed.
+ */
+/* static */ bool ServerNetworkGameSocketHandler::AllowConnection()
+{
+	extern byte _network_clients_connected;
+	return _network_clients_connected < MAX_CLIENTS && _network_game_info.clients_on < _settings_client.network.max_clients;
+}
+
+/** Send the packets for the server sockets. */
+/* static */ void ServerNetworkGameSocketHandler::Send()
+{
+	NetworkClientSocket *cs;
+	FOR_ALL_CLIENT_SOCKETS(cs) {
+		if (cs->writable) {
+			cs->Send_Packets();
+
+			if (cs->status == STATUS_MAP) {
+				/* This client is in the middle of a map-send, call the function for that */
+				cs->SendMap();
+			}
+		}
+	}
+}
+
 static void NetworkHandleCommandQueue(NetworkClientSocket *cs);
 
 /***********
diff --git a/src/network/network_server.h b/src/network/network_server.h
index 691411519..c5bc049f1 100644
--- a/src/network/network_server.h
+++ b/src/network/network_server.h
@@ -15,6 +15,7 @@
 #ifdef ENABLE_NETWORK
 
 #include "network_internal.h"
+#include "core/tcp_listen.h"
 
 class ServerNetworkGameSocketHandler;
 typedef ServerNetworkGameSocketHandler NetworkClientSocket;
@@ -22,7 +23,7 @@ typedef Pool<NetworkClientSocket, ClientIndex, 8, MAX_CLIENT_SLOTS> NetworkClien
 extern NetworkClientSocketPool _networkclientsocket_pool;
 
 /** Class for handling the server side of the game connection. */
-class ServerNetworkGameSocketHandler : public NetworkClientSocketPool::PoolItem<&_networkclientsocket_pool>, public NetworkGameSocketHandler {
+class ServerNetworkGameSocketHandler : public NetworkClientSocketPool::PoolItem<&_networkclientsocket_pool>, public NetworkGameSocketHandler, public TCPListenHandler<ServerNetworkGameSocketHandler, PACKET_SERVER_FULL, PACKET_SERVER_BANNED> {
 protected:
 	DECLARE_GAME_RECEIVE_COMMAND(PACKET_CLIENT_JOIN);
 	DECLARE_GAME_RECEIVE_COMMAND(PACKET_CLIENT_COMPANY_INFO);
@@ -76,6 +77,19 @@ public:
 	NetworkRecvStatus SendCommand(const CommandPacket *cp);
 	NetworkRecvStatus SendCompanyUpdate();
 	NetworkRecvStatus SendConfigUpdate();
+
+	static void Send();
+	static void AcceptConnection(SOCKET s, const NetworkAddress &address);
+	static bool AllowConnection();
+
+	/**
+	 * Get the name used by the listener.
+	 * @return the name to show in debug logs and the like.
+	 */
+	static const char *GetName()
+	{
+		return "server";
+	}
 };
 
 void NetworkServer_Tick(bool send_frame);