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

1 files changed, 178 insertions, 0 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 */