Quake/QW/client/net.h

/*
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.h -- quake's interface to the networking layer

#define	PORT_ANY	-1

typedef struct
{
	byte	ip[4];
	unsigned short	port;
	unsigned short	pad;
} netadr_t;

extern	netadr_t	net_local_adr;
extern	netadr_t	net_from;		// address of who sent the packet
extern	sizebuf_t	net_message;

extern	cvar_t	hostname;

extern	int		net_socket;

void		NET_Init (int port);
void		NET_Shutdown (void);
qboolean	NET_GetPacket (void);
void		NET_SendPacket (int length, void *data, netadr_t to);

qboolean	NET_CompareAdr (netadr_t a, netadr_t b);
qboolean	NET_CompareBaseAdr (netadr_t a, netadr_t b);
char		*NET_AdrToString (netadr_t a);
char		*NET_BaseAdrToString (netadr_t a);
qboolean	NET_StringToAdr (char *s, netadr_t *a);
qboolean NET_IsClientLegal(netadr_t *adr);

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

#define	OLD_AVG		0.99		// total = oldtotal*OLD_AVG + new*(1-OLD_AVG)

#define	MAX_LATENT	32

typedef struct
{
	qboolean	fatal_error;

	float		last_received;		// for timeouts

// the statistics are cleared at each client begin, because
// the server connecting process gives a bogus picture of the data
	float		frame_latency;		// rolling average
	float		frame_rate;

	int			drop_count;			// dropped packets, cleared each level
	int			good_count;			// cleared each level

	netadr_t	remote_address;
	int			qport;

// bandwidth estimator
	double		cleartime;			// if realtime > nc->cleartime, free to go
	double		rate;				// seconds / byte

// sequencing variables
	int			incoming_sequence;
	int			incoming_acknowledged;
	int			incoming_reliable_acknowledged;	// single bit

	int			incoming_reliable_sequence;		// single bit, maintained local

	int			outgoing_sequence;
	int			reliable_sequence;			// single bit
	int			last_reliable_sequence;		// sequence number of last send

// reliable staging and holding areas
	sizebuf_t	message;		// writing buffer to send to server
	byte		message_buf[MAX_MSGLEN];

	int			reliable_length;
	byte		reliable_buf[MAX_MSGLEN];	// unacked reliable message

// time and size data to calculate bandwidth
	int			outgoing_size[MAX_LATENT];
	double		outgoing_time[MAX_LATENT];
} netchan_t;

extern	int	net_drop;		// packets dropped before this one

void Netchan_Init (void);
void Netchan_Transmit (netchan_t *chan, int length, byte *data);
void Netchan_OutOfBand (netadr_t adr, int length, byte *data);
void Netchan_OutOfBandPrint (netadr_t adr, char *format, ...);
qboolean Netchan_Process (netchan_t *chan);
void Netchan_Setup (netchan_t *chan, netadr_t adr, int qport);

qboolean Netchan_CanPacket (netchan_t *chan);
qboolean Netchan_CanReliable (netchan_t *chan);