(svn r8083) -Codechange: make a NetworkSocketHandler as base for all sockets and move a little of NetworkClientState functionality to the NetworkSocketHandler. Move the rest of the NetworkClientState to the new NetworkTCPSocketHandler class/struct, which is not yet implemented in an object oriented manner. The UDP socket handler now extends the NetworkSocketHandler instead of having a reference to a NetworkClientState.

7 files changed, 208 insertions, 117 deletions

diff --git a/src/network/core/core.h b/src/network/core/core.h
index c6dc05591..f88fd0116 100644
--- a/src/network/core/core.h
+++ b/src/network/core/core.h
@@ -5,9 +5,61 @@
 
 #ifdef ENABLE_NETWORK
 
+#include "os_abstraction.h"
+
 bool NetworkCoreInitialize(void);
 void NetworkCoreShutdown(void);
 
+typedef enum {
+	NETWORK_RECV_STATUS_OKAY,             ///< Everything is okay
+	NETWORK_RECV_STATUS_DESYNC,           ///< A desync did occur
+	NETWORK_RECV_STATUS_SAVEGAME,         ///< Something went wrong (down)loading the savegame
+	NETWORK_RECV_STATUS_CONN_LOST,        ///< The conection is 'just' lost
+	NETWORK_RECV_STATUS_MALFORMED_PACKET, ///< We apparently send a malformed packet
+	NETWORK_RECV_STATUS_SERVER_ERROR,     ///< The server told us we made an error
+	NETWORK_RECV_STATUS_SERVER_FULL,      ///< The server is full
+	NETWORK_RECV_STATUS_SERVER_BANNED,    ///< The server has banned us
+	NETWORK_RECV_STATUS_CLOSE_QUERY,      ///< Done quering the server
+} NetworkRecvStatus;
+
+/**
+ * SocketHandler for all network sockets in OpenTTD.
+ */
+class NetworkSocketHandler {
+public:
+	/* TODO: make socket & has_quit protected once the TCP stuff
+	 *is in a real class too */
+	bool has_quit; ///< Whether the current client has quit/send a bad packet
+	SOCKET sock;   ///< The socket currently connected to
+public:
+	NetworkSocketHandler() { this->sock = INVALID_SOCKET; this->has_quit = false; }
+	virtual ~NetworkSocketHandler() { this->Close(); }
+
+	/** Really close the socket */
+	virtual void Close() {}
+
+	/**
+	 * Close the current connection; for TCP this will be mostly equivalent
+	 * to Close(), but for UDP it just means the packet has to be dropped.
+	 * @return new status of the connection.
+	 */
+	virtual NetworkRecvStatus CloseConnection() { this->has_quit = true; return NETWORK_RECV_STATUS_OKAY; }
+
+	/**
+	 * Whether this socket is currently bound to a socket.
+	 * @return true when the socket is bound, false otherwise
+	 */
+	bool IsConnected() { return this->sock != INVALID_SOCKET; }
+
+	/**
+	 * Whether the current client connected to the socket has quit.
+	 * In the case of UDP, for example, once a client quits (send bad
+	 * data), the socket in not closed; only the packet is dropped.
+	 * @return true when the current client has quit, false otherwise
+	 */
+	bool HasClientQuit() { return this->has_quit; }
+};
+
 #endif /* ENABLE_NETWORK */
 
 #endif /* NETWORK_CORE_H */
diff --git a/src/network/core/packet.cpp b/src/network/core/packet.cpp
index 511e0c675..fe10af48f 100644
--- a/src/network/core/packet.cpp
+++ b/src/network/core/packet.cpp
@@ -6,7 +6,6 @@
 #include "../../macros.h"
 #include "../../string.h"
 #include "../../helpers.hpp"
-#include "../network_data.h"
 
 #include "packet.h"
 
@@ -111,17 +110,15 @@ void NetworkSend_string(Packet *packet, const char* data)
  */
 
 
-extern NetworkRecvStatus CloseConnection(NetworkClientState *cs);
-
 /** Is it safe to read from the packet, i.e. didn't we run over the buffer ? */
-static inline bool CanReadFromPacket(NetworkClientState *cs, const Packet *packet, const uint bytes_to_read)
+static inline bool CanReadFromPacket(NetworkSocketHandler *cs, const Packet *packet, const uint bytes_to_read)
 {
-	/* Don't allow reading from a closed socket */
-	if (HasClientQuit(cs)) return false;
+	/* Don't allow reading from a quit client/client who send bad data */
+	if (cs->HasClientQuit()) return false;
 
 	/* Check if variable is within packet-size */
 	if (packet->pos + bytes_to_read > packet->size) {
-		CloseConnection(cs);
+		cs->CloseConnection();
 		return false;
 	}
 
@@ -138,7 +135,7 @@ void NetworkRecv_ReadPacketSize(Packet *packet)
 	packet->size += (uint16)packet->buffer[1] << 8;
 }
 
-uint8 NetworkRecv_uint8(NetworkClientState *cs, Packet *packet)
+uint8 NetworkRecv_uint8(NetworkSocketHandler *cs, Packet *packet)
 {
 	uint8 n;
 
@@ -148,7 +145,7 @@ uint8 NetworkRecv_uint8(NetworkClientState *cs, Packet *packet)
 	return n;
 }
 
-uint16 NetworkRecv_uint16(NetworkClientState *cs, Packet *packet)
+uint16 NetworkRecv_uint16(NetworkSocketHandler *cs, Packet *packet)
 {
 	uint16 n;
 
@@ -159,7 +156,7 @@ uint16 NetworkRecv_uint16(NetworkClientState *cs, Packet *packet)
 	return n;
 }
 
-uint32 NetworkRecv_uint32(NetworkClientState *cs, Packet *packet)
+uint32 NetworkRecv_uint32(NetworkSocketHandler *cs, Packet *packet)
 {
 	uint32 n;
 
@@ -172,7 +169,7 @@ uint32 NetworkRecv_uint32(NetworkClientState *cs, Packet *packet)
 	return n;
 }
 
-uint64 NetworkRecv_uint64(NetworkClientState *cs, Packet *packet)
+uint64 NetworkRecv_uint64(NetworkSocketHandler *cs, Packet *packet)
 {
 	uint64 n;
 
@@ -190,13 +187,13 @@ uint64 NetworkRecv_uint64(NetworkClientState *cs, Packet *packet)
 }
 
 /** Reads a string till it finds a '\0' in the stream */
-void NetworkRecv_string(NetworkClientState *cs, Packet *p, char *buffer, size_t size)
+void NetworkRecv_string(NetworkSocketHandler *cs, Packet *p, char *buffer, size_t size)
 {
 	PacketSize pos;
 	char *bufp = buffer;
 
 	/* Don't allow reading from a closed socket */
-	if (HasClientQuit(cs)) return;
+	if (cs->HasClientQuit()) return;
 
 	pos = p->pos;
 	while (--size > 0 && pos < p->size && (*buffer++ = p->buffer[pos++]) != '\0') {}
diff --git a/src/network/core/packet.h b/src/network/core/packet.h
index e42c65d5c..65ddec72c 100644
--- a/src/network/core/packet.h
+++ b/src/network/core/packet.h
@@ -6,23 +6,12 @@
 #ifdef ENABLE_NETWORK
 
 #include "config.h"
+#include "core.h"
 
 /**
  * @file packet.h Basic functions to create, fill and read packets.
  */
 
-typedef struct NetworkClientState NetworkClientState;
-
-/**
- * Queries the network client state struct to determine whether
- * the client has quit. It indirectly also queries whether the
- * packet is corrupt as the connection will be closed if it is
- * reading beyond the boundary of the received packet.
- * @param cs the state to query
- * @param true if the connection should be considered dropped
- */
-bool HasClientQuit(const NetworkClientState *cs);
-
 typedef uint16 PacketSize; ///< Size of the whole packet.
 typedef uint8  PacketType; ///< Identifier for the packet
 
@@ -58,11 +47,11 @@ void NetworkSend_uint64(Packet *packet, uint64 data);
 void NetworkSend_string(Packet *packet, const char* data);
 
 void NetworkRecv_ReadPacketSize(Packet *packet);
-uint8  NetworkRecv_uint8 (NetworkClientState *cs, Packet *packet);
-uint16 NetworkRecv_uint16(NetworkClientState *cs, Packet *packet);
-uint32 NetworkRecv_uint32(NetworkClientState *cs, Packet *packet);
-uint64 NetworkRecv_uint64(NetworkClientState *cs, Packet *packet);
-void   NetworkRecv_string(NetworkClientState *cs, Packet *packet, char* buffer, size_t size);
+uint8  NetworkRecv_uint8 (NetworkSocketHandler *cs, Packet *packet);
+uint16 NetworkRecv_uint16(NetworkSocketHandler *cs, Packet *packet);
+uint32 NetworkRecv_uint32(NetworkSocketHandler *cs, Packet *packet);
+uint64 NetworkRecv_uint64(NetworkSocketHandler *cs, Packet *packet);
+void   NetworkRecv_string(NetworkSocketHandler *cs, Packet *packet, char* buffer, size_t size);
 
 #endif /* ENABLE_NETWORK */
 
diff --git a/src/network/core/tcp.cpp b/src/network/core/tcp.cpp
index 98b5d8d5d..54271de57 100644
--- a/src/network/core/tcp.cpp
+++ b/src/network/core/tcp.cpp
@@ -18,6 +18,26 @@
  * @file tcp.c Basic functions to receive and send TCP packets.
  */
 
+/** Very ugly temporary hack !!! */
+void NetworkTCPSocketHandler::Initialize()
+{
+	this->sock              = INVALID_SOCKET;
+
+	this->index             = 0;
+	this->last_frame        = 0;
+	this->last_frame_server = 0;
+	this->lag_test          = 0;
+
+	this->status            = STATUS_INACTIVE;
+	this->has_quit          = false;
+	this->writable          = false;
+
+	this->packet_queue      = NULL;
+	this->packet_recv       = NULL;
+
+	this->command_queue     = NULL;
+}
+
 /**
  * Functions to help NetworkRecv_Packet/NetworkSend_Packet a bit
  *  A socket can make errors. When that happens this handles what to do.
@@ -25,10 +45,11 @@
  * For servers: close connection and that is it
  * @param cs the client to close the connection of
  * @return the new status
+ * TODO: needs to be splitted when using client and server socket packets
  */
-NetworkRecvStatus CloseConnection(NetworkClientState *cs)
+NetworkRecvStatus NetworkTCPSocketHandler::CloseConnection()
 {
-	NetworkCloseClient(cs);
+	NetworkCloseClient(this);
 
 	/* Clients drop back to the main menu */
 	if (!_network_server && _networking) {
@@ -43,23 +64,13 @@ NetworkRecvStatus CloseConnection(NetworkClientState *cs)
 }
 
 /**
- * Whether the client has quit or not (used in packet.c)
- * @param cs the client to check
- * @return true if the client has quit
- */
-bool HasClientQuit(const NetworkClientState *cs)
-{
-	return cs->has_quit;
-}
-
-/**
  * This function puts the packet in the send-queue and it is send as
  * soon as possible. This is the next tick, or maybe one tick later
  * if the OS-network-buffer is full)
  * @param packet the packet to send
  * @param cs     the client to send to
  */
-void NetworkSend_Packet(Packet *packet, NetworkClientState *cs)
+void NetworkSend_Packet(Packet *packet, NetworkTCPSocketHandler *cs)
 {
 	Packet *p;
 	assert(packet != NULL);
@@ -89,31 +100,31 @@ void NetworkSend_Packet(Packet *packet, NetworkClientState *cs)
  *   3) sending took too long
  * @param cs the client to send the packets for
  */
-bool NetworkSend_Packets(NetworkClientState *cs)
+bool NetworkSend_Packets(NetworkTCPSocketHandler *cs)
 {
 	ssize_t res;
 	Packet *p;
 
 	/* We can not write to this socket!! */
 	if (!cs->writable) return false;
-	if (cs->socket == INVALID_SOCKET) return false;
+	if (!cs->IsConnected()) return false;
 
 	p = cs->packet_queue;
 	while (p != NULL) {
-		res = send(cs->socket, (const char*)p->buffer + p->pos, p->size - p->pos, 0);
+		res = send(cs->sock, (const char*)p->buffer + p->pos, p->size - p->pos, 0);
 		if (res == -1) {
 			int err = GET_LAST_ERROR();
 			if (err != EWOULDBLOCK) {
 				/* Something went wrong.. close client! */
 				DEBUG(net, 0, "send failed with error %d", err);
-				CloseConnection(cs);
+				cs->CloseConnection();
 				return false;
 			}
 			return true;
 		}
 		if (res == 0) {
 			/* Client/server has left us :( */
-			CloseConnection(cs);
+			cs->CloseConnection();
 			return false;
 		}
 
@@ -139,14 +150,14 @@ bool NetworkSend_Packets(NetworkClientState *cs)
  * @param status the variable to store the status into
  * @return the received packet (or NULL when it didn't receive one)
  */
-Packet *NetworkRecv_Packet(NetworkClientState *cs, NetworkRecvStatus *status)
+Packet *NetworkRecv_Packet(NetworkTCPSocketHandler *cs, NetworkRecvStatus *status)
 {
 	ssize_t res;
 	Packet *p;
 
 	*status = NETWORK_RECV_STATUS_OKAY;
 
-	if (cs->socket == INVALID_SOCKET) return NULL;
+	if (!cs->IsConnected()) return NULL;
 
 	if (cs->packet_recv == NULL) {
 		cs->packet_recv = MallocT<Packet>(1);
@@ -161,14 +172,14 @@ Packet *NetworkRecv_Packet(NetworkClientState *cs, NetworkRecvStatus *status)
 	/* Read packet size */
 	if (p->pos < sizeof(PacketSize)) {
 		while (p->pos < sizeof(PacketSize)) {
-			/* Read the size of the packet */
-			res = recv(cs->socket, (char*)p->buffer + p->pos, sizeof(PacketSize) - p->pos, 0);
+		/* Read the size of the packet */
+			res = recv(cs->sock, (char*)p->buffer + p->pos, sizeof(PacketSize) - p->pos, 0);
 			if (res == -1) {
 				int err = GET_LAST_ERROR();
 				if (err != EWOULDBLOCK) {
 					/* Something went wrong... (104 is connection reset by peer) */
 					if (err != 104) DEBUG(net, 0, "recv failed with error %d", err);
-					*status = CloseConnection(cs);
+					*status = cs->CloseConnection();
 					return NULL;
 				}
 				/* Connection would block, so stop for now */
@@ -176,7 +187,7 @@ Packet *NetworkRecv_Packet(NetworkClientState *cs, NetworkRecvStatus *status)
 			}
 			if (res == 0) {
 				/* Client/server has left */
-				*status = CloseConnection(cs);
+				*status = cs->CloseConnection();
 				return NULL;
 			}
 			p->pos += res;
@@ -185,20 +196,20 @@ Packet *NetworkRecv_Packet(NetworkClientState *cs, NetworkRecvStatus *status)
 		NetworkRecv_ReadPacketSize(p);
 
 		if (p->size > SEND_MTU) {
-			*status = CloseConnection(cs);
+			*status = cs->CloseConnection();
 			return NULL;
 		}
 	}
 
 	/* Read rest of packet */
 	while (p->pos < p->size) {
-		res = recv(cs->socket, (char*)p->buffer + p->pos, p->size - p->pos, 0);
+		res = recv(cs->sock, (char*)p->buffer + p->pos, p->size - p->pos, 0);
 		if (res == -1) {
 			int err = GET_LAST_ERROR();
 			if (err != EWOULDBLOCK) {
 				/* Something went wrong... (104 is connection reset by peer) */
 				if (err != 104) DEBUG(net, 0, "recv failed with error %d", err);
-				*status = CloseConnection(cs);
+				*status = cs->CloseConnection();
 				return NULL;
 			}
 			/* Connection would block */
@@ -206,7 +217,7 @@ Packet *NetworkRecv_Packet(NetworkClientState *cs, NetworkRecvStatus *status)
 		}
 		if (res == 0) {
 			/* Client/server has left */
-			*status = CloseConnection(cs);
+			*status = cs->CloseConnection();
 			return NULL;
 		}
 
diff --git a/src/network/core/tcp.h b/src/network/core/tcp.h
index ab5c9b8e0..c15f851aa 100644
--- a/src/network/core/tcp.h
+++ b/src/network/core/tcp.h
@@ -6,6 +6,7 @@
 #ifdef ENABLE_NETWORK
 
 #include "os_abstraction.h"
+#include "core.h"
 #include "packet.h"
 
 /**
@@ -54,9 +55,54 @@ enum {
 	PACKET_END                   ///< Must ALWAYS be on the end of this list!! (period)
 };
 
-void NetworkSend_Packet(Packet *packet, NetworkClientState *cs);
-Packet *NetworkRecv_Packet(NetworkClientState *cs, NetworkRecvStatus *status);
-bool NetworkSend_Packets(NetworkClientState *cs);
+typedef struct CommandPacket {
+	struct CommandPacket *next;
+	PlayerByte player; ///< player that is executing the command
+	uint32 cmd;        ///< command being executed
+	uint32 p1;         ///< parameter p1
+	uint32 p2;         ///< parameter p2
+	TileIndex tile;    ///< tile command being executed on
+	char text[80];
+	uint32 frame;      ///< the frame in which this packet is executed
+	byte callback;     ///< any callback function executed upon successful completion of the command
+} CommandPacket;
+
+typedef enum {
+	STATUS_INACTIVE,   ///< The client is not connected nor active
+	STATUS_AUTH,       ///< The client is authorized
+	STATUS_MAP_WAIT,   ///< The client is waiting as someone else is downloading the map
+	STATUS_MAP,        ///< The client is downloading the map
+	STATUS_DONE_MAP,   ///< The client has downloaded the map
+	STATUS_PRE_ACTIVE, ///< The client is catching up the delayed frames
+	STATUS_ACTIVE,     ///< The client is an active player in the game
+} ClientStatus;
+
+/** Base socket handler for all TCP sockets */
+class NetworkTCPSocketHandler : public NetworkSocketHandler {
+/* TODO: rewrite into a proper class */
+public:
+	uint16 index;
+	uint32 last_frame;
+	uint32 last_frame_server;
+	byte lag_test; // This byte is used for lag-testing the client
+
+	ClientStatus status;
+	bool writable; // is client ready to write to?
+
+	Packet *packet_queue; // Packets that are awaiting delivery
+	Packet *packet_recv; // Partially received packet
+
+	CommandPacket *command_queue; // The command-queue awaiting delivery
+
+	NetworkRecvStatus CloseConnection();
+	void Initialize();
+};
+
+
+
+void NetworkSend_Packet(Packet *packet, NetworkTCPSocketHandler *cs);
+Packet *NetworkRecv_Packet(NetworkTCPSocketHandler *cs, NetworkRecvStatus *status);
+bool NetworkSend_Packets(NetworkTCPSocketHandler *cs);
 
 #endif /* ENABLE_NETWORK */
 
diff --git a/src/network/core/udp.cpp b/src/network/core/udp.cpp
index ddc4cadfb..c3709aa10 100644
--- a/src/network/core/udp.cpp
+++ b/src/network/core/udp.cpp
@@ -13,12 +13,6 @@
  * @file udp.c Basic functions to receive and send UDP packets.
  */
 
-/** Initialize the sockets with an INVALID_SOCKET */
-NetworkUDPSocketHandler::NetworkUDPSocketHandler()
-{
-	this->udp = INVALID_SOCKET;
-}
-
 /**
  * Start listening on the given host and port.
  * @param udp       the place where the (references to the) UDP are stored
@@ -34,8 +28,8 @@ bool NetworkUDPSocketHandler::Listen(const uint32 host, const uint16 port, const
 	/* Make sure socket is closed */
 	this->Close();
 
-	this->udp = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
-	if (this->udp == INVALID_SOCKET) {
+	this->sock = socket(AF_INET, SOCK_DGRAM, IPPROTO_UDP);
+	if (!this->IsConnected()) {
 		DEBUG(net, 0, "[udp] failed to start UDP listener");
 		return false;
 	}
@@ -44,9 +38,9 @@ bool NetworkUDPSocketHandler::Listen(const uint32 host, const uint16 port, const
 	{
 		unsigned long blocking = 1;
 #ifndef BEOS_NET_SERVER
-		ioctlsocket(this->udp, FIONBIO, &blocking);
+		ioctlsocket(this->sock, FIONBIO, &blocking);
 #else
-		setsockopt(this->udp, SOL_SOCKET, SO_NONBLOCK, &blocking, NULL);
+		setsockopt(this->sock, SOL_SOCKET, SO_NONBLOCK, &blocking, NULL);
 #endif
 	}
 
@@ -55,7 +49,7 @@ bool NetworkUDPSocketHandler::Listen(const uint32 host, const uint16 port, const
 	sin.sin_addr.s_addr = host;
 	sin.sin_port = htons(port);
 
-	if (bind(this->udp, (struct sockaddr*)&sin, sizeof(sin)) != 0) {
+	if (bind(this->sock, (struct sockaddr*)&sin, sizeof(sin)) != 0) {
 		DEBUG(net, 0, "[udp] bind failed on %s:%i", inet_ntoa(*(struct in_addr *)&host), port);
 		return false;
 	}
@@ -64,7 +58,7 @@ bool NetworkUDPSocketHandler::Listen(const uint32 host, const uint16 port, const
 		/* Enable broadcast */
 		unsigned long val = 1;
 #ifndef BEOS_NET_SERVER // will work around this, some day; maybe.
-		setsockopt(this->udp, SOL_SOCKET, SO_BROADCAST, (char *) &val , sizeof(val));
+		setsockopt(this->sock, SOL_SOCKET, SO_BROADCAST, (char *) &val , sizeof(val));
 #endif
 	}
 
@@ -79,12 +73,17 @@ bool NetworkUDPSocketHandler::Listen(const uint32 host, const uint16 port, const
  */
 void NetworkUDPSocketHandler::Close()
 {
-	if (this->udp == INVALID_SOCKET) return;
+	if (!this->IsConnected()) return;
 
-	closesocket(this->udp);
-	this->udp = INVALID_SOCKET;
+	closesocket(this->sock);
+	this->sock = INVALID_SOCKET;
 }
 
+NetworkRecvStatus NetworkUDPSocketHandler::CloseConnection()
+{
+	this->has_quit = true;
+	return NETWORK_RECV_STATUS_OKAY;
+}
 
 /**
  * Send a packet over UDP
@@ -99,7 +98,7 @@ void NetworkUDPSocketHandler::SendPacket(Packet *p, const struct sockaddr_in *re
 	NetworkSend_FillPacketSize(p);
 
 	/* Send the buffer */
-	res = sendto(this->udp, (const char*)p->buffer, p->size, 0, (struct sockaddr *)recv, sizeof(*recv));
+	res = sendto(this->sock, (const char*)p->buffer, p->size, 0, (struct sockaddr *)recv, sizeof(*recv));
 
 	/* Check for any errors, but ignore it otherwise */
 	if (res == -1) DEBUG(net, 1, "[udp] sendto failed with: %i", GET_LAST_ERROR());
@@ -117,13 +116,13 @@ void NetworkUDPSocketHandler::ReceivePackets()
 	Packet p;
 	int packet_len;
 
-	if (this->udp == INVALID_SOCKET) return;
+	if (!this->IsConnected()) return;
 
 	packet_len = sizeof(p.buffer);
 	client_len = sizeof(client_addr);
 
 	/* Try to receive anything */
-	nbytes = recvfrom(this->udp, (char*)p.buffer, packet_len, 0, (struct sockaddr *)&client_addr, &client_len);
+	nbytes = recvfrom(this->sock, (char*)p.buffer, packet_len, 0, (struct sockaddr *)&client_addr, &client_len);
 
 	/* We got some bytes for the base header of the packet. */
 	if (nbytes > 2) {
@@ -170,9 +169,9 @@ void NetworkUDPSocketHandler::Send_GRFIdentifier(Packet *p, const GRFConfig *c)
 void NetworkUDPSocketHandler::Recv_GRFIdentifier(Packet *p, GRFConfig *c)
 {
 	uint j;
-	c->grfid = NetworkRecv_uint32(&this->cs, p);
+	c->grfid = NetworkRecv_uint32(this, p);
 	for (j = 0; j < sizeof(c->md5sum); j++) {
-		c->md5sum[j] = NetworkRecv_uint8(&this->cs, p);
+		c->md5sum[j] = NetworkRecv_uint8(this, p);
 	}
 }
 
@@ -246,7 +245,7 @@ void NetworkUDPSocketHandler::Send_NetworkGameInfo(Packet *p, const NetworkGameI
  */
 void NetworkUDPSocketHandler::Recv_NetworkGameInfo(Packet *p, NetworkGameInfo *info)
 {
-	info->game_info_version = NetworkRecv_uint8(&this->cs, p);
+	info->game_info_version = NetworkRecv_uint8(this, p);
 
 	/*
 	 *              Please observe the order.
@@ -260,7 +259,7 @@ void NetworkUDPSocketHandler::Recv_NetworkGameInfo(Packet *p, NetworkGameInfo *i
 		case 4: {
 			GRFConfig **dst = &info->grfconfig;
 			uint i;
-			uint num_grfs = NetworkRecv_uint8(&this->cs, p);
+			uint num_grfs = NetworkRecv_uint8(this, p);
 
 			for (i = 0; i < num_grfs; i++) {
 				GRFConfig *c = CallocT<GRFConfig>(1);
@@ -273,31 +272,31 @@ void NetworkUDPSocketHandler::Recv_NetworkGameInfo(Packet *p, NetworkGameInfo *i
 			}
 		} /* Fallthrough */
 		case 3:
-			info->game_date      = NetworkRecv_uint32(&this->cs, p);
-			info->start_date     = NetworkRecv_uint32(&this->cs, p);
+			info->game_date      = NetworkRecv_uint32(this, p);
+			info->start_date     = NetworkRecv_uint32(this, p);
 			/* Fallthrough */
 		case 2:
-			info->companies_max  = NetworkRecv_uint8 (&this->cs, p);
-			info->companies_on   = NetworkRecv_uint8 (&this->cs, p);
-			info->spectators_max = NetworkRecv_uint8 (&this->cs, p);
+			info->companies_max  = NetworkRecv_uint8 (this, p);
+			info->companies_on   = NetworkRecv_uint8 (this, p);
+			info->spectators_max = NetworkRecv_uint8 (this, p);
 			/* Fallthrough */
 		case 1:
-			NetworkRecv_string(&this->cs, p, info->server_name,     sizeof(info->server_name));
-			NetworkRecv_string(&this->cs, p, info->server_revision, sizeof(info->server_revision));
-			info->server_lang    = NetworkRecv_uint8 (&this->cs, p);
-			info->use_password   = NetworkRecv_uint8 (&this->cs, p);
-			info->clients_max    = NetworkRecv_uint8 (&this->cs, p);
-			info->clients_on     = NetworkRecv_uint8 (&this->cs, p);
-			info->spectators_on  = NetworkRecv_uint8 (&this->cs, p);
+			NetworkRecv_string(this, p, info->server_name,     sizeof(info->server_name));
+			NetworkRecv_string(this, p, info->server_revision, sizeof(info->server_revision));
+			info->server_lang    = NetworkRecv_uint8 (this, p);
+			info->use_password   = NetworkRecv_uint8 (this, p);
+			info->clients_max    = NetworkRecv_uint8 (this, p);
+			info->clients_on     = NetworkRecv_uint8 (this, p);
+			info->spectators_on  = NetworkRecv_uint8 (this, p);
 			if (info->game_info_version < 3) { // 16 bits dates got scrapped and are read earlier
-				info->game_date    = NetworkRecv_uint16(&this->cs, p) + DAYS_TILL_ORIGINAL_BASE_YEAR;
-				info->start_date   = NetworkRecv_uint16(&this->cs, p) + DAYS_TILL_ORIGINAL_BASE_YEAR;
+				info->game_date    = NetworkRecv_uint16(this, p) + DAYS_TILL_ORIGINAL_BASE_YEAR;
+				info->start_date   = NetworkRecv_uint16(this, p) + DAYS_TILL_ORIGINAL_BASE_YEAR;
 			}
-			NetworkRecv_string(&this->cs, p, info->map_name, sizeof(info->map_name));
-			info->map_width      = NetworkRecv_uint16(&this->cs, p);
-			info->map_height     = NetworkRecv_uint16(&this->cs, p);
-			info->map_set        = NetworkRecv_uint8 (&this->cs, p);
-			info->dedicated      = (NetworkRecv_uint8(&this->cs, p) != 0);
+			NetworkRecv_string(this, p, info->map_name, sizeof(info->map_name));
+			info->map_width      = NetworkRecv_uint16(this, p);
+			info->map_height     = NetworkRecv_uint16(this, p);
+			info->map_set        = NetworkRecv_uint8 (this, p);
+			info->dedicated      = (NetworkRecv_uint8(this, p) != 0);
 	}
 }
 
@@ -313,13 +312,12 @@ void NetworkUDPSocketHandler::HandleUDPPacket(Packet *p, const struct sockaddr_i
 {
 	PacketUDPType type;
 
-	/* Fake a client, so we can see when there is an illegal packet */
-	this->cs.socket = INVALID_SOCKET;
-	this->cs.has_quit = false;
+	/* New packet == new client, which has not quit yet */
+	this->has_quit = false;
 
-	type = (PacketUDPType)NetworkRecv_uint8(&this->cs, p);
+	type = (PacketUDPType)NetworkRecv_uint8(this, p);
 
-	switch (this->cs.has_quit ? PACKET_UDP_END : type) {
+	switch (this->HasClientQuit() ? PACKET_UDP_END : type) {
 		UDP_COMMAND(PACKET_UDP_CLIENT_FIND_SERVER);
 		UDP_COMMAND(PACKET_UDP_SERVER_RESPONSE);
 		UDP_COMMAND(PACKET_UDP_CLIENT_DETAIL_INFO);
@@ -333,7 +331,7 @@ void NetworkUDPSocketHandler::HandleUDPPacket(Packet *p, const struct sockaddr_i
 		UDP_COMMAND(PACKET_UDP_SERVER_NEWGRFS);
 
 		default:
-			if (!this->cs.has_quit) {
+			if (this->HasClientQuit()) {
 				DEBUG(net, 0, "[udp] received invalid packet type %d from %s:%d", type,  inet_ntoa(client_addr->sin_addr), ntohs(client_addr->sin_port));
 			} else {
 				DEBUG(net, 0, "[udp] received illegal packet from %s:%d", inet_ntoa(client_addr->sin_addr), ntohs(client_addr->sin_port));
@@ -351,8 +349,8 @@ void NetworkUDPSocketHandler::HandleUDPPacket(Packet *p, const struct sockaddr_i
 #define DEFINE_UNAVAILABLE_UDP_RECEIVE_COMMAND(type) \
 void NetworkUDPSocketHandler::NetworkPacketReceive_## type ##_command(\
 		Packet *p, const struct sockaddr_in *client_addr) { \
-	DEBUG(net, 0, "[udp] received packet on wrong port from %s:%d", \
-			inet_ntoa(client_addr->sin_addr), ntohs(client_addr->sin_port)); \
+	DEBUG(net, 0, "[udp] received packet type %d on wrong port from %s:%d", \
+			type, inet_ntoa(client_addr->sin_addr), ntohs(client_addr->sin_port)); \
 }
 
 DEFINE_UNAVAILABLE_UDP_RECEIVE_COMMAND(PACKET_UDP_CLIENT_FIND_SERVER);
diff --git a/src/network/core/udp.h b/src/network/core/udp.h
index 755829600..9bb743841 100644
--- a/src/network/core/udp.h
+++ b/src/network/core/udp.h
@@ -6,11 +6,11 @@
 #ifdef ENABLE_NETWORK
 
 #include "os_abstraction.h"
+#include "core.h"
 #include "game.h"
 #include "packet.h"
 #include "../../newgrf_config.h"
 #include "../../debug.h"
-#include "../network_data.h"
 
 /**
  * @file udp.h Basic functions to receive and send UDP packets.
@@ -91,11 +91,11 @@ enum PacketUDPType {
 
 #define DECLARE_UDP_RECEIVE_COMMAND(type) virtual void NetworkPacketReceive_## type ##_command(Packet *p, const struct sockaddr_in *)
 
-class NetworkUDPSocketHandler {
-private:
-	SOCKET udp;
+/** Base socket handler for all UDP sockets */
+class NetworkUDPSocketHandler : public NetworkSocketHandler {
 protected:
-	NetworkClientState cs;
+	NetworkRecvStatus CloseConnection();
+
 	/* Declare all possible packets here. If it can be received by the
 	 * a specific handler, it has to be implemented. */
 	DECLARE_UDP_RECEIVE_COMMAND(PACKET_UDP_CLIENT_FIND_SERVER);
@@ -121,10 +121,8 @@ protected:
 	 */
 	virtual void HandleIncomingNetworkGameInfoGRFConfig(GRFConfig *config) { NOT_REACHED(); }
 public:
-	NetworkUDPSocketHandler();
 	virtual ~NetworkUDPSocketHandler() { this->Close(); }
 
-	bool IsListening() { return this->udp != INVALID_SOCKET; }
 	bool Listen(uint32 host, uint16 port, bool broadcast);
 	void Close();