net_dgrm.c

quake1 dos源代码最新版本

		// find the search start location
		prevCvarName = MSG_ReadString();
		if (*prevCvarName)
		{
			var = Cvar_FindVar (prevCvarName);
			if (!var)
				return NULL;
			var = var->next;
		}
		else
			var = cvar_list;	// 2001-09-18 New cvar system by Maddes

		// search for the next server cvar
		while (var)
		{
			if (var->flags & CVAR_SERVERINFO)	// 2001-09-18 New cvar system by Maddes
				break;
			var = var->next;
		}

		// send the response

		SZ_Clear(&net_message);
		// save space for the header, filled in later
		MSG_WriteLong(&net_message, 0);
		MSG_WriteByte(&net_message, CCREP_RULE_INFO);
		if (var)
		{
			MSG_WriteString(&net_message, var->name);
			MSG_WriteString(&net_message, var->string);
		}
		*((int *)net_message.data) = BigLong(NETFLAG_CTL | (net_message.cursize & NETFLAG_LENGTH_MASK));
		dfunc.Write (acceptsock, net_message.data, net_message.cursize, &clientaddr);
		SZ_Clear(&net_message);

		return NULL;
	}

	if (command != CCREQ_CONNECT)
		return NULL;

	if (strcmp(MSG_ReadString(), "QUAKE") != 0)
		return NULL;

	if (MSG_ReadByte() != NET_PROTOCOL_VERSION)
	{
		SZ_Clear(&net_message);
		// save space for the header, filled in later
		MSG_WriteLong(&net_message, 0);
		MSG_WriteByte(&net_message, CCREP_REJECT);
		MSG_WriteString(&net_message, "Incompatible version.\n");
		*((int *)net_message.data) = BigLong(NETFLAG_CTL | (net_message.cursize & NETFLAG_LENGTH_MASK));
		dfunc.Write (acceptsock, net_message.data, net_message.cursize, &clientaddr);
		SZ_Clear(&net_message);
		return NULL;
	}

#ifdef BAN_TEST
	// check for a ban
	if (clientaddr.sa_family == AF_INET)
	{
		unsigned long testAddr;
		testAddr = ((struct sockaddr_in *)&clientaddr)->sin_addr.s_addr;
		if ((testAddr & banMask) == banAddr)
		{
			SZ_Clear(&net_message);
			// save space for the header, filled in later
			MSG_WriteLong(&net_message, 0);
			MSG_WriteByte(&net_message, CCREP_REJECT);
			MSG_WriteString(&net_message, "You have been banned.\n");
			*((int *)net_message.data) = BigLong(NETFLAG_CTL | (net_message.cursize & NETFLAG_LENGTH_MASK));
			dfunc.Write (acceptsock, net_message.data, net_message.cursize, &clientaddr);
			SZ_Clear(&net_message);
			return NULL;
		}
	}
#endif

	// see if this guy is already connected
	for (s = net_activeSockets; s; s = s->next)
	{
		if (s->driver != net_driverlevel)
			continue;
		ret = dfunc.AddrCompare(&clientaddr, &s->addr);
		if (ret >= 0)
		{
			// is this a duplicate connection reqeust?
			if (ret == 0 && net_time - s->connecttime < 2.0)
			{
				// yes, so send a duplicate reply
				SZ_Clear(&net_message);
				// save space for the header, filled in later
				MSG_WriteLong(&net_message, 0);
				MSG_WriteByte(&net_message, CCREP_ACCEPT);
				dfunc.GetSocketAddr(s->socket, &newaddr);
				MSG_WriteLong(&net_message, dfunc.GetSocketPort(&newaddr));
				*((int *)net_message.data) = BigLong(NETFLAG_CTL | (net_message.cursize & NETFLAG_LENGTH_MASK));
				dfunc.Write (acceptsock, net_message.data, net_message.cursize, &clientaddr);
				SZ_Clear(&net_message);
				return NULL;
			}
			// it's somebody coming back in from a crash/disconnect
			// so close the old qsocket and let their retry get them back in
			NET_Close(s);
			return NULL;
		}
	}

	// allocate a QSocket
	sock = NET_NewQSocket ();
	if (sock == NULL)
	{
		// no room; try to let him know
		SZ_Clear(&net_message);
		// save space for the header, filled in later
		MSG_WriteLong(&net_message, 0);
		MSG_WriteByte(&net_message, CCREP_REJECT);
		MSG_WriteString(&net_message, "Server is full.\n");
		*((int *)net_message.data) = BigLong(NETFLAG_CTL | (net_message.cursize & NETFLAG_LENGTH_MASK));
		dfunc.Write (acceptsock, net_message.data, net_message.cursize, &clientaddr);
		SZ_Clear(&net_message);
		return NULL;
	}

	// allocate a network socket
	newsock = dfunc.OpenSocket(0);
	if (newsock == -1)
	{
		NET_FreeQSocket(sock);
		return NULL;
	}

	// connect to the client
	if (dfunc.Connect (newsock, &clientaddr) == -1)
	{
		dfunc.CloseSocket(newsock);
		NET_FreeQSocket(sock);
		return NULL;
	}

	// everything is allocated, just fill in the details
	sock->socket = newsock;
	sock->landriver = net_landriverlevel;
	sock->addr = clientaddr;
	strcpy(sock->address, dfunc.AddrToString(&clientaddr));

	// send him back the info about the server connection he has been allocated
	SZ_Clear(&net_message);
	// save space for the header, filled in later
	MSG_WriteLong(&net_message, 0);
	MSG_WriteByte(&net_message, CCREP_ACCEPT);
	dfunc.GetSocketAddr(newsock, &newaddr);
	MSG_WriteLong(&net_message, dfunc.GetSocketPort(&newaddr));
//	MSG_WriteString(&net_message, dfunc.AddrToString(&newaddr));
	*((int *)net_message.data) = BigLong(NETFLAG_CTL | (net_message.cursize & NETFLAG_LENGTH_MASK));
	dfunc.Write (acceptsock, net_message.data, net_message.cursize, &clientaddr);
	SZ_Clear(&net_message);

	return sock;
}

qsocket_t *Datagram_CheckNewConnections (void)
{
	qsocket_t *ret = NULL;

	for (net_landriverlevel = 0; net_landriverlevel < net_numlandrivers; net_landriverlevel++)
		if (net_landrivers[net_landriverlevel].initialized)
			if ((ret = _Datagram_CheckNewConnections ()) != NULL)
				break;
	return ret;
}


static void _Datagram_SearchForHosts (qboolean xmit)
{
	int		ret;
	int		n;
	int		i;
	struct qsockaddr readaddr;
	struct qsockaddr myaddr;
	int		control;

	dfunc.GetSocketAddr (dfunc.controlSock, &myaddr);
	if (xmit)
	{
		SZ_Clear(&net_message);
		// save space for the header, filled in later
		MSG_WriteLong(&net_message, 0);
		MSG_WriteByte(&net_message, CCREQ_SERVER_INFO);
		MSG_WriteString(&net_message, "QUAKE");
		MSG_WriteByte(&net_message, NET_PROTOCOL_VERSION);
		*((int *)net_message.data) = BigLong(NETFLAG_CTL | (net_message.cursize & NETFLAG_LENGTH_MASK));
		dfunc.Broadcast(dfunc.controlSock, net_message.data, net_message.cursize);
		SZ_Clear(&net_message);
	}

	while ((ret = dfunc.Read (dfunc.controlSock, net_message.data, net_message.maxsize, &readaddr)) > 0)
	{
		if (ret < sizeof(int))
			continue;
		net_message.cursize = ret;

		// don't answer our own query
		if (dfunc.AddrCompare(&readaddr, &myaddr) >= 0)
			continue;

		// is the cache full?
		if (hostCacheCount == HOSTCACHESIZE)
			continue;

		MSG_BeginReading ();
		control = BigLong(*((int *)net_message.data));
		MSG_ReadLong();
		if (control == -1)
			continue;
		if ((control & (~NETFLAG_LENGTH_MASK)) !=  NETFLAG_CTL)
			continue;
		if ((control & NETFLAG_LENGTH_MASK) != ret)
			continue;

		if (MSG_ReadByte() != CCREP_SERVER_INFO)
			continue;

		dfunc.GetAddrFromName(MSG_ReadString(), &readaddr);
		// search the cache for this server
		for (n = 0; n < hostCacheCount; n++)
			if (dfunc.AddrCompare(&readaddr, &hostcache[n].addr) == 0)
				break;

		// is it already there?
		if (n < hostCacheCount)
			continue;

		// add it
		hostCacheCount++;
		strcpy(hostcache[n].name, MSG_ReadString());
		strcpy(hostcache[n].map, MSG_ReadString());
		hostcache[n].users = MSG_ReadByte();
		hostcache[n].maxusers = MSG_ReadByte();
		if (MSG_ReadByte() != NET_PROTOCOL_VERSION)
		{
			strcpy(hostcache[n].cname, hostcache[n].name);
			hostcache[n].cname[14] = 0;
			strcpy(hostcache[n].name, "*");
			strcat(hostcache[n].name, hostcache[n].cname);
		}
		Q_memcpy(&hostcache[n].addr, &readaddr, sizeof(struct qsockaddr));
		hostcache[n].driver = net_driverlevel;
		hostcache[n].ldriver = net_landriverlevel;
		strcpy(hostcache[n].cname, dfunc.AddrToString(&readaddr));

		// check for a name conflict
		for (i = 0; i < hostCacheCount; i++)
		{
			if (i == n)
				continue;
			if (Q_strcasecmp (hostcache[n].name, hostcache[i].name) == 0)
			{
				i = strlen(hostcache[n].name);
				if (i < 15 && hostcache[n].name[i-1] > '8')
				{
					hostcache[n].name[i] = '0';
					hostcache[n].name[i+1] = 0;
				}
				else
					hostcache[n].name[i-1]++;
				i = -1;
			}
		}
	}
}

void Datagram_SearchForHosts (qboolean xmit)
{
	for (net_landriverlevel = 0; net_landriverlevel < net_numlandrivers; net_landriverlevel++)
	{
		if (hostCacheCount == HOSTCACHESIZE)
			break;
		if (net_landrivers[net_landriverlevel].initialized)
			_Datagram_SearchForHosts (xmit);
	}
}


static qsocket_t *_Datagram_Connect (char *host)
{
	struct qsockaddr sendaddr;
	struct qsockaddr readaddr;
	qsocket_t	*sock;
	int			newsock;
	int			ret;
	int			reps;
	double		start_time;
	int			control;
	char		*reason;

	// see if we can resolve the host name
	if (dfunc.GetAddrFromName(host, &sendaddr) == -1)
		return NULL;

	newsock = dfunc.OpenSocket (0);
	if (newsock == -1)
		return NULL;

	sock = NET_NewQSocket ();
	if (sock == NULL)
		goto ErrorReturn2;
	sock->socket = newsock;
	sock->landriver = net_landriverlevel;

	// connect to the host
	if (dfunc.Connect (newsock, &sendaddr) == -1)
		goto ErrorReturn;

	// send the connection request
	Con_Printf("trying...\n"); SCR_UpdateScreen ();
	start_time = net_time;

	for (reps = 0; reps < 3; reps++)
	{
		SZ_Clear(&net_message);
		// save space for the header, filled in later
		MSG_WriteLong(&net_message, 0);
		MSG_WriteByte(&net_message, CCREQ_CONNECT);
		MSG_WriteString(&net_message, "QUAKE");
		MSG_WriteByte(&net_message, NET_PROTOCOL_VERSION);
		*((int *)net_message.data) = BigLong(NETFLAG_CTL | (net_message.cursize & NETFLAG_LENGTH_MASK));
		dfunc.Write (newsock, net_message.data, net_message.cursize, &sendaddr);
		SZ_Clear(&net_message);
		do
		{
			ret = dfunc.Read (newsock, net_message.data, net_message.maxsize, &readaddr);
			// if we got something, validate it
			if (ret > 0)
			{
				// is it from the right place?
				if (sfunc.AddrCompare(&readaddr, &sendaddr) != 0)
				{
#ifdef DEBUG
					Con_Printf("wrong reply address\n");
					Con_Printf("Expected: %s\n", StrAddr (&sendaddr));
					Con_Printf("Received: %s\n", StrAddr (&readaddr));
					SCR_UpdateScreen ();
#endif
					ret = 0;
					continue;
				}

				if (ret < sizeof(int))
				{
					ret = 0;
					continue;
				}

				net_message.cursize = ret;
				MSG_BeginReading ();

				control = BigLong(*((int *)net_message.data));
				MSG_ReadLong();
				if (control == -1)
				{
					ret = 0;
					continue;
				}
				if ((control & (~NETFLAG_LENGTH_MASK)) !=  NETFLAG_CTL)
				{
					ret = 0;
					continue;
				}
				if ((control & NETFLAG_LENGTH_MASK) != ret)
				{
					ret = 0;
					continue;
				}
			}
		}
		while (ret == 0 && (SetNetTime() - start_time) < 2.5);
		if (ret)
			break;
		Con_Printf("still trying...\n"); SCR_UpdateScreen ();
		start_time = SetNetTime();
	}

	if (ret == 0)
	{
		reason = "No Response";
		Con_Printf("%s\n", reason);
		strcpy(m_return_reason, reason);
		goto ErrorReturn;
	}

	if (ret == -1)
	{
		reason = "Network Error";
		Con_Printf("%s\n", reason);
		strcpy(m_return_reason, reason);
		goto ErrorReturn;
	}

	ret = MSG_ReadByte();
	if (ret == CCREP_REJECT)
	{
		reason = MSG_ReadString();
		Con_Printf(reason);
		strncpy(m_return_reason, reason, 31);
		goto ErrorReturn;
	}

	if (ret == CCREP_ACCEPT)
	{
		Q_memcpy(&sock->addr, &sendaddr, sizeof(struct qsockaddr));
		dfunc.SetSocketPort (&sock->addr, MSG_ReadLong());
	}
	else
	{
		reason = "Bad Response";
		Con_Printf("%s\n", reason);
		strcpy(m_return_reason, reason);
		goto ErrorReturn;
	}

	dfunc.GetNameFromAddr (&sendaddr, sock->address);

	Con_Printf ("Connection accepted\n");
	sock->lastMessageTime = SetNetTime();

	// switch the connection to the specified address
	if (dfunc.Connect (newsock, &sock->addr) == -1)
	{
		reason = "Connect to Game failed";
		Con_Printf("%s\n", reason);
		strcpy(m_return_reason, reason);
		goto ErrorReturn;
	}

	m_return_onerror = false;
	return sock;

ErrorReturn:
	NET_FreeQSocket(sock);
ErrorReturn2:
	dfunc.CloseSocket(newsock);
	if (m_return_onerror)
	{
		key_dest = key_menu;
		m_state = m_return_state;
		m_return_onerror = false;
	}
	return NULL;
}

qsocket_t *Datagram_Connect (char *host)
{
	qsocket_t *ret = NULL;

	for (net_landriverlevel = 0; net_landriverlevel < net_numlandrivers; net_landriverlevel++)
		if (net_landrivers[net_landriverlevel].initialized)
			if ((ret = _Datagram_Connect (host)) != NULL)
				break;
	return ret;
}