net_main.c

/*
Copyright (C) 1996-1997 Id Software, Inc.

This program 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; either version 2
of the License, or (at your option) any later version.

This program 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 this program; if not, write to the Free Software
Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.

*/
// net_main.c

#include "quakedef.h"

qsocket_t	*net_activeSockets = NULL;
qsocket_t	*net_freeSockets = NULL;
static int			net_numsockets = 0;

qboolean	tcpipAvailable = false;

int			net_hostport;
int			DEFAULTnet_hostport = 26900;

char		my_tcpip_address[NET_NAMELEN];

static qboolean	listening = false;

qboolean	slistInProgress = false;
qboolean	slistSilent = false;
qboolean	slistLocal = true;
#define IS_LOOP_DRIVER(p) ((p) == &net_drivers[0])
static double	slistStartTime;
static int		slistLastShown;

static void Slist_Send(void);
static void Slist_Poll(void);
static PollProcedure	slistSendProcedure = {NULL, 0.0, Slist_Send};
static PollProcedure	slistPollProcedure = {NULL, 0.0, Slist_Poll};


static sizebuf_t _net_message_message;
static qmsg_t _net_message = { 0, false, &_net_message_message };
qmsg_t *net_message = &_net_message;
int net_activeconnections = 0;

int messagesSent = 0;
int messagesReceived = 0;
int unreliableMessagesSent = 0;
int unreliableMessagesReceived = 0;

cvar_t	net_messagetimeout = {"net_messagetimeout","300"};
cvar_t	net_connecttimeout = {"net_connecttimeout","10"}; // qkick/qflood protection
cvar_t	hostname = {"hostname", "UNNAMED"};
cvar_t	pq_password = {"pq_password", ""}; // password protection for server
cvar_t	rcon_password = {"rcon_password", ""}; // rcon password
cvar_t	rcon_server = {"rcon_server", ""}; // rcon server
char	server_name[MAX_QPATH]; // use the current server if rcon_server is not set

// rcon
#define RCON_BUFF_SIZE	65536 // was 8192
char		rcon_buff[RCON_BUFF_SIZE];
sizebuf_t	rcon_message = {false, false, (byte *)rcon_buff, RCON_BUFF_SIZE, 0};
qboolean	rcon_active = false;

net_driver_t *net_driver;

double			net_time;

double SetNetTime(void)
{
	net_time = Sys_DoubleTime();
	return net_time;
}


/*
===================
NET_NewQSocket

Called by drivers when a new communications endpoint is required
The sequence and buffer fields will be filled in properly
===================
*/
qsocket_t *NET_NewQSocket (void)
{
	qsocket_t	*sock;

	if (!net_freeSockets)
		return NULL;

	if (net_activeconnections >= svs.maxclients)
		return NULL;

	// get one from free list
	sock = net_freeSockets;
	net_freeSockets = sock->next;

	// add it to active list
	sock->next = net_activeSockets;
	net_activeSockets = sock;

	sock->disconnected = false;
	sock->connecttime = net_time;
	strcpy(sock->address, "UNSET ADDRESS");
	sock->driver = net_driver;
	sock->socket = 0;
	sock->driverdata = NULL;
	sock->canSend = true;
	sock->sendNext = false;
	sock->lastMessageTime = net_time;
	sock->ackSequence = 0;
	sock->sendSequence = 0;
	sock->unreliableSendSequence = 0;
	sock->sendMessageLength = 0;
	sock->receiveSequence = 0;
	sock->unreliableReceiveSequence = 0;
	sock->receiveMessageLength = 0;

	return sock;
}


void NET_FreeQSocket(qsocket_t *sock)
{
	qsocket_t	*s;

	// remove it from active list
	if (sock == net_activeSockets)
		net_activeSockets = net_activeSockets->next;
	else
	{
		for (s = net_activeSockets; s; s = s->next)
			if (s->next == sock)
			{
				s->next = sock->next;
				break;
			}
		if (!s)
			Sys_Error ("NET_FreeQSocket: not active");
	}

	// add it to free list
	sock->next = net_freeSockets;
	net_freeSockets = sock;
	sock->disconnected = true;
}


static void NET_Listen_f (void)
{
	int i;

	if (Cmd_Argc () != 2)
	{
		Con_Printf ("\"listen\" is \"%u\"\n", listening ? 1 : 0);
		return;
	}

	listening = atoi(Cmd_Argv(1)) ? true : false;

	for (i = 0; i < net_numdrivers;i++) 
	{
		net_driver = &net_drivers[i];
		if (net_driver->initialized == false)
			continue;
		net_driver->Listen(listening);
	}
}


static void MaxPlayers_f (void)
{
	int 	n;

	if (Cmd_Argc () != 2)
	{
		Con_Printf ("\"maxplayers\" is \"%u\"\n", svs.maxclients);
		return;
	}

	if (sv.active)
	{
		Con_Printf ("maxplayers can not be changed while a server is running.\n");
		return;
	}

	n = atoi(Cmd_Argv(1));
	if (n < 1)
		n = 1;

	if (n > svs.maxclientslimit)
	{
		n = svs.maxclientslimit;
		Con_Printf ("\"maxplayers\" set to \"%u\"\n", n);
	}

	if ((n == 1) && listening)
		Cbuf_AddText ("listen 0\n");

	if ((n > 1) && (!listening))
		Cbuf_AddText ("listen 1\n");

	svs.maxclients = n;
	if (n == 1)
	{
		Cvar_Set("deathmatch", "0");
		Cvar_Set("coop", "0");
	}
	else 
	{
		if (coop.value)
			Cvar_Set("deathmatch", "0");
		else
			Cvar_Set("deathmatch", "1");
	}
}


static void NET_Port_f (void)
{
	int 	n;

	if (Cmd_Argc () != 2)
	{
		Con_Printf ("\"port\" is \"%u\"\n", net_hostport);
		return;
	}

	n = atoi(Cmd_Argv(1));
	if (n < 1 || n > 65534)
	{
		Con_Printf ("Bad value, must be between 1 and 65534\n");
		return;
	}

	DEFAULTnet_hostport = n;
	net_hostport = n;

	if (listening)
	{
		// force a change to the new port
		Cbuf_AddText ("listen 0\n");
		Cbuf_AddText ("listen 1\n");
	}
}


static void PrintSlistHeader(void)
{
	Con_Printf("Server          Map             Users\n");
	Con_Printf("--------------- --------------- -----\n");
	slistLastShown = 0;
}


static void PrintSlist(void)
{
	int n;

	for (n = slistLastShown; n < hostCacheCount; n++)
	{
		if (hostcache[n].maxusers)
			Con_Printf("%-15.15s %-15.15s %2u/%2u\n", hostcache[n].name, hostcache[n].map, hostcache[n].users, hostcache[n].maxusers);
		else
			Con_Printf("%-15.15s %-15.15s\n", hostcache[n].name, hostcache[n].map);
	}
	slistLastShown = n;
}


static void PrintSlistTrailer(void)
{
	if (hostCacheCount)
		Con_Printf("== end list ==\n\n");
	else
		Con_Printf("No Hexen II servers found.\n\n");
}


void NET_Slist_f (void)
{
	if (slistInProgress)
		return;

	if (!slistSilent)
	{
		Con_Printf("Looking for Hexen II servers...\n");
		PrintSlistHeader();
	}

	slistInProgress = true;
	slistStartTime = Sys_DoubleTime();

	SchedulePollProcedure(&slistSendProcedure, 0.0);
	SchedulePollProcedure(&slistPollProcedure, 0.1);

	hostCacheCount = 0;
}


static void Slist_Send(void)
{
	int i;

	for (i = 0; i < net_numdrivers; i++) 
	{
		net_driver = &net_drivers[i];

		// Only list the loop driver if slistLocal is true
		if (!slistLocal && IS_LOOP_DRIVER(net_driver))
			continue;
		if (net_driver->initialized == false)
			continue;
		net_driver->SearchForHosts(true);
	}

	if ((Sys_DoubleTime() - slistStartTime) < 0.5)
		SchedulePollProcedure(&slistSendProcedure, 0.75);
}


static void Slist_Poll(void)
{
	int i;

	for (i = 0; i < net_numdrivers; i++) 
	{
		net_driver = &net_drivers[i];

		// Only list the loop driver if slistLocal is true
		if (!slistLocal && IS_LOOP_DRIVER(net_driver))
			continue;
		if (net_driver->initialized == false)
			continue;
		net_driver->SearchForHosts(false);
	}

	if (! slistSilent)
		PrintSlist();

	if ((Sys_DoubleTime() - slistStartTime) < 1.5)
	{
		SchedulePollProcedure(&slistPollProcedure, 0.1);
		return;
	}

	if (! slistSilent)
		PrintSlistTrailer();

	slistInProgress = false;
	slistSilent = false;
	slistLocal = true;
}


/*
===================
NET_Connect
===================
*/

int hostCacheCount = 0;
hostcache_t hostcache[HOSTCACHESIZE];

qsocket_t *NET_Connect (char *host)
{
	qsocket_t		*ret;
	int i, n;
	int				numdrivers = net_numdrivers;

	SetNetTime();

	if (host && *host == 0)
		host = NULL;

	if (host)
	{
		if (strcasecmp (host, "local") == 0)
		{
			numdrivers = 1;
			goto JustDoIt;
		}

		if (hostCacheCount)
		{
			for (n = 0; n < hostCacheCount; n++)
				if (strcasecmp (host, hostcache[n].name) == 0)
				{
					host = hostcache[n].cname;
					break;
				}

			if (n < hostCacheCount)
				goto JustDoIt;
		}
	}

	slistSilent = host ? true : false;
	NET_Slist_f ();

	while(slistInProgress)
		NET_Poll();

	if (host == NULL)
	{
		if (hostCacheCount != 1)
			return NULL;
		host = hostcache[0].cname;
		Con_Printf("Connecting to...\n%s @ %s\n\n", hostcache[0].name, host);
	}

	if (hostCacheCount)
		for (n = 0; n < hostCacheCount; n++)
			if (strcasecmp (host, hostcache[n].name) == 0)
			{
				host = hostcache[n].cname;
				break;
			}

JustDoIt:
	for (i = 0; i < numdrivers; i++) 
	{
		net_driver = &net_drivers[i];
		if (net_driver->initialized == false)
			continue;

		ret = net_driver->Connect(host);
		if (ret)
			return ret;
	}

	/* ProQuake - this has always annoyed me so I commented it out
	if (host)
	{
		Con_Printf("\n");
		PrintSlistHeader();
		PrintSlist();
		PrintSlistTrailer();
	}
	*/
	
	return NULL;
}


/*
===================
NET_CheckNewConnections
===================
*/
qsocket_t *NET_CheckNewConnections (void)
{
	int i;
	qsocket_t *ret = NULL;

	SetNetTime();

	for (i = 0; i < net_numdrivers; i++) 
	{
		net_driver = &net_drivers[i];
		if (net_driver->initialized == false)
			continue;
		if (!IS_LOOP_DRIVER(net_driver) && listening == false)
			continue;

		ret = net_driver->CheckNewConnections();
		if (ret)
			break;
	}

	return ret;
}

/*
===================
NET_Close
===================
*/
void NET_Close (qsocket_t *sock)
{
	if (!sock)
		return;

	if (sock->disconnected)
		return;

	SetNetTime();

	// call the driver_Close function
	sock->driver->Close(sock);

	NET_FreeQSocket(sock);
}


/*
=================
NET_GetMessage

If there is a complete message, return it in net_message

returns 0 if no data is waiting
returns 1 if a message was received
returns -1 if connection is invalid
=================
*/
int	NET_GetMessage (qsocket_t *sock)
{
	int ret;

	if (!sock)
		return -1;

	if (sock->disconnected)
	{
		Con_Printf("NET_GetMessage: disconnected socket\n");
		return -1;
	}

	SetNetTime();

	ret = sock->driver->QGetMessage(sock);

	// see if this connection has timed out (not for loop)
	if (ret == 0 && (!IS_LOOP_DRIVER(sock->driver)))
	{
		if (net_time - sock->lastMessageTime > net_messagetimeout.value)
		{
			NET_Close(sock);
			return -1;
		}

		// qflood/qkick protection
		if (net_time - sock->lastMessageTime > net_connecttimeout.value && sv.active && 
			host_client && sock == host_client->netconnection && !strcmp(host_client->name, "unconnected"))
		{
			NET_Close(sock);
			return -1;
		}
	}


	if (ret > 0)
	{
		if (!IS_LOOP_DRIVER(sock->driver))
		{
			sock->lastMessageTime = net_time;
			if (ret == 1)
				messagesReceived++;
			else if (ret == 2)
				unreliableMessagesReceived++;
		}
	}

	return ret;
}


/*
==================
NET_SendMessage

Try to send a complete length+message unit over the reliable stream.
returns 0 if the message cannot be delivered reliably, but the connection
		is still considered valid
returns 1 if the message was sent properly
returns -1 if the connection died
==================
*/
int NET_SendMessage (qsocket_t *sock, sizebuf_t *data)
{
	int		r;
	
	if (!sock)
		return -1;

	if (sock->disconnected)
	{
		Con_Printf("NET_SendMessage: disconnected socket\n");
		return -1;
	}

	SetNetTime();

	r = sock->driver->QSendMessage(sock, data);

	if (r == 1 && !IS_LOOP_DRIVER(sock->driver))
		messagesSent++;

	return r;
}


int NET_SendUnreliableMessage (qsocket_t *sock, sizebuf_t *data)
{
	int		r;
	
	if (!sock)
		return -1;

	if (sock->disconnected)
	{
		Con_Printf("NET_SendMessage: disconnected socket\n");
		return -1;
	}

	SetNetTime();

	r = sock->driver->SendUnreliableMessage(sock, data);

	if (r == 1 && !IS_LOOP_DRIVER(sock->driver))
		unreliableMessagesSent++;

	return r;
}


/*
==================
NET_CanSendMessage

Returns true or false if the given qsocket can currently accept a
message to be transmitted.
==================
*/
qboolean NET_CanSendMessage (qsocket_t *sock)
{
	int		r;
	
	if (!sock)
		return false;

	if (sock->disconnected)
		return false;

	SetNetTime();

	r = sock->driver->CanSendMessage(sock);

	return r;
}


int NET_SendToAll(sizebuf_t *data, int blocktime)
{
	return NET_SendToAll2 (data, blocktime, false);
}

int NET_SendToAll2 (sizebuf_t *data, int blocktime, qboolean nolocals)
{
	double		start;
	int			i;
	int			count = 0;
	qboolean msg_init[MAX_SCOREBOARD]; /* data written */
	qboolean msg_sent[MAX_SCOREBOARD]; /* send completed */

	for (i = 0, host_client = svs.clients ; i < svs.maxclients ; i++, host_client++)
	{
		if (host_client->netconnection && host_client->active) 
		{

			// Loopback driver guarantees delivery, skip checks
			if (IS_LOOP_DRIVER(host_client->netconnection->driver))
			{
				if (!nolocals)
					NET_SendMessage(host_client->netconnection, data);

				msg_init[i] = true;
				msg_sent[i] = true;
				continue;
			}
			count++;
			msg_init[i] = false;
			msg_sent[i] = false;
		}
		else
		{
			msg_init[i] = true;
			msg_sent[i] = true;
		}
	}

	start = Sys_DoubleTime();
	while (count)
	{
		count = 0;
		for (i = 0, host_client = svs.clients ; i < svs.maxclients ; i++, host_client++)
		{
			if (!msg_init[i])
			{
				if (NET_CanSendMessage (host_client->netconnection))
				{
					msg_init[i] = true;
					NET_SendMessage(host_client->netconnection, data);
				}
				else
				{
					NET_GetMessage (host_client->netconnection);
				}
				count++;
				continue;
			}

			if (!msg_sent[i])
			{
				if (NET_CanSendMessage (host_client->netconnection))
				{
					msg_sent[i] = true;
				}
				else
				{
					NET_GetMessage (host_client->netconnection);
				}
				count++;
				continue;
			}
		}
		if ((Sys_DoubleTime() - start) > blocktime)
			break;
	}
	return count;
}


//=============================================================================

/*
====================
NET_Init
====================
*/

void NET_Init (void)
{
	int i, num_inited;
	int			controlSocket;
	qsocket_t	*s;

	i = COM_CheckParm ("-port");
	if (!i)
		i = COM_CheckParm ("-udpport");

	if (i)
	{
		if (i < com_argc - 1)
			DEFAULTnet_hostport = atoi (com_argv[i + 1]);
		else
			Sys_Error ("NET_Init: you must specify a number after -port");
	}
	net_hostport = DEFAULTnet_hostport;

	if (COM_CheckParm("-listen") || cls.state == ca_dedicated)
		listening = true;
	net_numsockets = svs.maxclientslimit;
	if (cls.state != ca_dedicated)
		net_numsockets++;

	SetNetTime();

	for (i = 0; i < net_numsockets; i++)
	{
		s = (qsocket_t *)Hunk_AllocName(sizeof(qsocket_t), "qsocket");
		s->next = net_freeSockets;
		net_freeSockets = s;
		s->disconnected = true;
	}

	// allocate space for network message buffer
	SZ_Alloc (&_net_message_message, NET_MAXMESSAGE);

	Cvar_RegisterVariable (&net_messagetimeout, NULL);
	Cvar_RegisterVariable (&net_connecttimeout, NULL); // qkick/qflood protection
	Cvar_RegisterVariable (&hostname, NULL);
	Cvar_RegisterVariable (&pq_password, NULL); // password protection for server
	Cvar_RegisterVariable (&rcon_password, NULL); // rcon password
	Cvar_RegisterVariable (&rcon_server, NULL); // rcon server

	Cmd_AddCommand ("slist", NET_Slist_f);
	Cmd_AddCommand ("listen", NET_Listen_f);
	Cmd_AddCommand ("maxplayers", MaxPlayers_f);
	Cmd_AddCommand ("port", NET_Port_f);

	// initialize all the drivers
	num_inited = 0;
	for (i = 0; i < net_numdrivers; i++) 
	{
		net_driver = &net_drivers[i];
		controlSocket = net_driver->Init();
		if (controlSocket == -1)
			continue;

		num_inited++;
		net_driver->initialized = true;
		net_driver->controlSock = controlSocket;

		if (listening)
			net_driver->Listen(true);
	}

	if (num_inited == 0 && cls.state == ca_dedicated)
		Sys_Error("Network not available!");

	if (*my_tcpip_address)
		Con_DPrintf("TCP/IP address %s\n", my_tcpip_address);
}

/*
====================
NET_Shutdown
====================
*/

void		NET_Shutdown (void)
{
	int i;
	qsocket_t	*sock;

	SetNetTime();

	for (sock = net_activeSockets; sock; sock = sock->next)
		NET_Close(sock);


	// shutdown the drivers
	for (i = 0; i < net_numdrivers; i++) 
	{
		net_driver = &net_drivers[i];
		if (net_driver->initialized == true)
		{
			net_driver->Shutdown();
			net_driver->initialized = false;
		}
	}
}


static PollProcedure *pollProcedureList = NULL;

void NET_Poll(void)
{
	PollProcedure *pp;

	SetNetTime();

// FIXME - A procedure could schedule itself to the head of the list, but
// wouldn't be executed until next frame/tic; problem?
	for (pp = pollProcedureList; pp; pp = pp->next)
	{
		if (pp->nextTime > net_time)
			break;
		pollProcedureList = pp->next;
		pp->procedure(pp->arg);
	}
}


void SchedulePollProcedure(PollProcedure *proc, double timeOffset)
{
	PollProcedure *pp, *prev;

	proc->nextTime = Sys_DoubleTime() + timeOffset;
	for (pp = pollProcedureList, prev = NULL; pp; pp = pp->next)
	{
		if (pp->nextTime >= proc->nextTime)
			break;
		prev = pp;
	}

	if (prev == NULL)
	{
		proc->next = pollProcedureList;
		pollProcedureList = proc;
		return;
	}

	proc->next = pp;
	prev->next = proc;
}