net_chan.c

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			Com_Printf( "%s:Dropped %i packets at %i\n"
			, NET_AdrToString( chan->remoteAddress )
			, chan->dropped
			, sequence );
		}
	}
	

	//
	// if this is the final framgent of a reliable message,
	// bump incoming_reliable_sequence 
	//
	if ( fragmented ) {
		// TTimo
		// make sure we add the fragments in correct order
		// either a packet was dropped, or we received this one too soon
		// we don't reconstruct the fragments. we will wait till this fragment gets to us again
		// (NOTE: we could probably try to rebuild by out of order chunks if needed)
		if ( sequence != chan->fragmentSequence ) {
			chan->fragmentSequence = sequence;
			chan->fragmentLength = 0;
		}

		// if we missed a fragment, dump the message
		if ( fragmentStart != chan->fragmentLength ) {
			if ( showdrop->integer || showpackets->integer ) {
				Com_Printf( "%s:Dropped a message fragment\n"
				, NET_AdrToString( chan->remoteAddress )
				, sequence);
			}
			// we can still keep the part that we have so far,
			// so we don't need to clear chan->fragmentLength
			return qfalse;
		}

		// copy the fragment to the fragment buffer
		if ( fragmentLength < 0 || msg->readcount + fragmentLength > msg->cursize ||
			chan->fragmentLength + fragmentLength > sizeof( chan->fragmentBuffer ) ) {
			if ( showdrop->integer || showpackets->integer ) {
				Com_Printf ("%s:illegal fragment length\n"
				, NET_AdrToString (chan->remoteAddress ) );
			}
			return qfalse;
		}

		Com_Memcpy( chan->fragmentBuffer + chan->fragmentLength, 
			msg->data + msg->readcount, fragmentLength );

		chan->fragmentLength += fragmentLength;

		// if this wasn't the last fragment, don't process anything
		if ( fragmentLength == FRAGMENT_SIZE ) {
			return qfalse;
		}

		if ( chan->fragmentLength > msg->maxsize ) {
			Com_Printf( "%s:fragmentLength %i > msg->maxsize\n"
				, NET_AdrToString (chan->remoteAddress ),
				chan->fragmentLength );
			return qfalse;
		}

		// copy the full message over the partial fragment

		// make sure the sequence number is still there
		*(int *)msg->data = LittleLong( sequence );

		Com_Memcpy( msg->data + 4, chan->fragmentBuffer, chan->fragmentLength );
		msg->cursize = chan->fragmentLength + 4;
		chan->fragmentLength = 0;
		msg->readcount = 4;	// past the sequence number
		msg->bit = 32;	// past the sequence number

		// TTimo
		// clients were not acking fragmented messages
		chan->incomingSequence = sequence;
		
		return qtrue;
	}

	//
	// the message can now be read from the current message pointer
	//
	chan->incomingSequence = sequence;

	return qtrue;
}


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

/*
===================
NET_CompareBaseAdr

Compares without the port
===================
*/
qboolean	NET_CompareBaseAdr (netadr_t a, netadr_t b)
{
	if (a.type != b.type)
		return qfalse;

	if (a.type == NA_LOOPBACK)
		return qtrue;

	if (a.type == NA_IP)
	{
		if (a.ip[0] == b.ip[0] && a.ip[1] == b.ip[1] && a.ip[2] == b.ip[2] && a.ip[3] == b.ip[3])
			return qtrue;
		return qfalse;
	}

	if (a.type == NA_IPX)
	{
		if ((memcmp(a.ipx, b.ipx, 10) == 0))
			return qtrue;
		return qfalse;
	}


	Com_Printf ("NET_CompareBaseAdr: bad address type\n");
	return qfalse;
}

const char	*NET_AdrToString (netadr_t a)
{
	static	char	s[64];

	if (a.type == NA_LOOPBACK) {
		Com_sprintf (s, sizeof(s), "loopback");
	} else if (a.type == NA_BOT) {
		Com_sprintf (s, sizeof(s), "bot");
	} else if (a.type == NA_IP) {
		Com_sprintf (s, sizeof(s), "%i.%i.%i.%i:%hu",
			a.ip[0], a.ip[1], a.ip[2], a.ip[3], BigShort(a.port));
	} else {
		Com_sprintf (s, sizeof(s), "%02x%02x%02x%02x.%02x%02x%02x%02x%02x%02x:%hu",
		a.ipx[0], a.ipx[1], a.ipx[2], a.ipx[3], a.ipx[4], a.ipx[5], a.ipx[6], a.ipx[7], a.ipx[8], a.ipx[9], 
		BigShort(a.port));
	}

	return s;
}


qboolean	NET_CompareAdr (netadr_t a, netadr_t b)
{
	if (a.type != b.type)
		return qfalse;

	if (a.type == NA_LOOPBACK)
		return qtrue;

	if (a.type == NA_IP)
	{
		if (a.ip[0] == b.ip[0] && a.ip[1] == b.ip[1] && a.ip[2] == b.ip[2] && a.ip[3] == b.ip[3] && a.port == b.port)
			return qtrue;
		return qfalse;
	}

	if (a.type == NA_IPX)
	{
		if ((memcmp(a.ipx, b.ipx, 10) == 0) && a.port == b.port)
			return qtrue;
		return qfalse;
	}

	Com_Printf ("NET_CompareAdr: bad address type\n");
	return qfalse;
}


qboolean	NET_IsLocalAddress( netadr_t adr ) {
	return adr.type == NA_LOOPBACK;
}



/*
=============================================================================

LOOPBACK BUFFERS FOR LOCAL PLAYER

=============================================================================
*/

// there needs to be enough loopback messages to hold a complete
// gamestate of maximum size
#define	MAX_LOOPBACK	16

typedef struct {
	byte	data[MAX_PACKETLEN];
	int		datalen;
} loopmsg_t;

typedef struct {
	loopmsg_t	msgs[MAX_LOOPBACK];
	int			get, send;
} loopback_t;

loopback_t	loopbacks[2];


qboolean	NET_GetLoopPacket (netsrc_t sock, netadr_t *net_from, msg_t *net_message)
{
	int		i;
	loopback_t	*loop;

	loop = &loopbacks[sock];

	if (loop->send - loop->get > MAX_LOOPBACK)
		loop->get = loop->send - MAX_LOOPBACK;

	if (loop->get >= loop->send)
		return qfalse;

	i = loop->get & (MAX_LOOPBACK-1);
	loop->get++;

	Com_Memcpy (net_message->data, loop->msgs[i].data, loop->msgs[i].datalen);
	net_message->cursize = loop->msgs[i].datalen;
	Com_Memset (net_from, 0, sizeof(*net_from));
	net_from->type = NA_LOOPBACK;
	return qtrue;

}


void NET_SendLoopPacket (netsrc_t sock, int length, const void *data, netadr_t to)
{
	int		i;
	loopback_t	*loop;

	loop = &loopbacks[sock^1];

	i = loop->send & (MAX_LOOPBACK-1);
	loop->send++;

	Com_Memcpy (loop->msgs[i].data, data, length);
	loop->msgs[i].datalen = length;
}

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


void NET_SendPacket( netsrc_t sock, int length, const void *data, netadr_t to ) {

	// sequenced packets are shown in netchan, so just show oob
	if ( showpackets->integer && *(int *)data == -1 )	{
		Com_Printf ("send packet %4i\n", length);
	}

	if ( to.type == NA_LOOPBACK ) {
		NET_SendLoopPacket (sock, length, data, to);
		return;
	}
	if ( to.type == NA_BOT ) {
		return;
	}
	if ( to.type == NA_BAD ) {
		return;
	}

	Sys_SendPacket( length, data, to );
}

/*
===============
NET_OutOfBandPrint

Sends a text message in an out-of-band datagram
================
*/
void QDECL NET_OutOfBandPrint( netsrc_t sock, netadr_t adr, const char *format, ... ) {
	va_list		argptr;
	char		string[MAX_MSGLEN];


	// set the header
	string[0] = -1;
	string[1] = -1;
	string[2] = -1;
	string[3] = -1;

	va_start( argptr, format );
	vsprintf( string+4, format, argptr );
	va_end( argptr );

	// send the datagram
	NET_SendPacket( sock, strlen( string ), string, adr );
}

/*
===============
NET_OutOfBandPrint

Sends a data message in an out-of-band datagram (only used for "connect")
================
*/
void QDECL NET_OutOfBandData( netsrc_t sock, netadr_t adr, byte *format, int len ) {
	byte		string[MAX_MSGLEN*2];
	int			i;
	msg_t		mbuf;

	// set the header
	string[0] = 0xff;
	string[1] = 0xff;
	string[2] = 0xff;
	string[3] = 0xff;

	for(i=0;i<len;i++) {
		string[i+4] = format[i];
	}

	mbuf.data = string;
	mbuf.cursize = len+4;
	Huff_Compress( &mbuf, 12);
	// send the datagram
	NET_SendPacket( sock, mbuf.cursize, mbuf.data, adr );
}

/*
=============
NET_StringToAdr

Traps "localhost" for loopback, passes everything else to system
=============
*/
qboolean	NET_StringToAdr( const char *s, netadr_t *a ) {
	qboolean	r;
	char	base[MAX_STRING_CHARS];
	char	*port;

	if (!strcmp (s, "localhost")) {
		Com_Memset (a, 0, sizeof(*a));
		a->type = NA_LOOPBACK;
		return qtrue;
	}

	// look for a port number
	Q_strncpyz( base, s, sizeof( base ) );
	port = strstr( base, ":" );
	if ( port ) {
		*port = 0;
		port++;
	}

	r = Sys_StringToAdr( base, a );

	if ( !r ) {
		a->type = NA_BAD;
		return qfalse;
	}

	// inet_addr returns this if out of range
	if ( a->ip[0] == 255 && a->ip[1] == 255 && a->ip[2] == 255 && a->ip[3] == 255 ) {
		a->type = NA_BAD;
		return qfalse;
	}

	if ( port ) {
		a->port = BigShort( (short)atoi( port ) );
	} else {
		a->port = BigShort( PORT_SERVER );
	}

	return qtrue;
}