sv_main.c

quakeIII源码这个不用我多说吧

Redirect all printfs
===============
*/
void SVC_RemoteCommand( netadr_t from, msg_t *msg ) {
	qboolean	valid;
	unsigned int time;
	char		remaining[1024];
	// TTimo - scaled down to accumulate, but not overflow anything network wise, print wise etc.
	// (OOB messages are the bottleneck here)
#define SV_OUTPUTBUF_LENGTH (1024 - 16)
	char		sv_outputbuf[SV_OUTPUTBUF_LENGTH];
	static unsigned int lasttime = 0;
	char *cmd_aux;

	// TTimo - https://zerowing.idsoftware.com/bugzilla/show_bug.cgi?id=534
	time = Com_Milliseconds();
	if (time<(lasttime+500)) {
		return;
	}
	lasttime = time;

	if ( !strlen( sv_rconPassword->string ) ||
		strcmp (Cmd_Argv(1), sv_rconPassword->string) ) {
		valid = qfalse;
		Com_Printf ("Bad rcon from %s:\n%s\n", NET_AdrToString (from), Cmd_Argv(2) );
	} else {
		valid = qtrue;
		Com_Printf ("Rcon from %s:\n%s\n", NET_AdrToString (from), Cmd_Argv(2) );
	}

	// start redirecting all print outputs to the packet
	svs.redirectAddress = from;
	Com_BeginRedirect (sv_outputbuf, SV_OUTPUTBUF_LENGTH, SV_FlushRedirect);

	if ( !strlen( sv_rconPassword->string ) ) {
		Com_Printf ("No rconpassword set on the server.\n");
	} else if ( !valid ) {
		Com_Printf ("Bad rconpassword.\n");
	} else {
		remaining[0] = 0;
		
		// https://zerowing.idsoftware.com/bugzilla/show_bug.cgi?id=543
		// get the command directly, "rcon <pass> <command>" to avoid quoting issues
		// extract the command by walking
		// since the cmd formatting can fuckup (amount of spaces), using a dumb step by step parsing
		cmd_aux = Cmd_Cmd();
		cmd_aux+=4;
		while(cmd_aux[0]==' ')
			cmd_aux++;
		while(cmd_aux[0] && cmd_aux[0]!=' ') // password
			cmd_aux++;
		while(cmd_aux[0]==' ')
			cmd_aux++;
		
		Q_strcat( remaining, sizeof(remaining), cmd_aux);
		
		Cmd_ExecuteString (remaining);

	}

	Com_EndRedirect ();
}

/*
=================
SV_ConnectionlessPacket

A connectionless packet has four leading 0xff
characters to distinguish it from a game channel.
Clients that are in the game can still send
connectionless packets.
=================
*/
void SV_ConnectionlessPacket( netadr_t from, msg_t *msg ) {
	char	*s;
	char	*c;

	MSG_BeginReadingOOB( msg );
	MSG_ReadLong( msg );		// skip the -1 marker

	if (!Q_strncmp("connect", &msg->data[4], 7)) {
		Huff_Decompress(msg, 12);
	}

	s = MSG_ReadStringLine( msg );
	Cmd_TokenizeString( s );

	c = Cmd_Argv(0);
	Com_DPrintf ("SV packet %s : %s\n", NET_AdrToString(from), c);

	if (!Q_stricmp(c, "getstatus")) {
		SVC_Status( from  );
  } else if (!Q_stricmp(c, "getinfo")) {
		SVC_Info( from );
	} else if (!Q_stricmp(c, "getchallenge")) {
		SV_GetChallenge( from );
	} else if (!Q_stricmp(c, "connect")) {
		SV_DirectConnect( from );
	} else if (!Q_stricmp(c, "ipAuthorize")) {
		SV_AuthorizeIpPacket( from );
	} else if (!Q_stricmp(c, "rcon")) {
		SVC_RemoteCommand( from, msg );
	} else if (!Q_stricmp(c, "disconnect")) {
		// if a client starts up a local server, we may see some spurious
		// server disconnect messages when their new server sees our final
		// sequenced messages to the old client
	} else {
		Com_DPrintf ("bad connectionless packet from %s:\n%s\n"
		, NET_AdrToString (from), s);
	}
}

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

/*
=================
SV_ReadPackets
=================
*/
void SV_PacketEvent( netadr_t from, msg_t *msg ) {
	int			i;
	client_t	*cl;
	int			qport;

	// check for connectionless packet (0xffffffff) first
	if ( msg->cursize >= 4 && *(int *)msg->data == -1) {
		SV_ConnectionlessPacket( from, msg );
		return;
	}

	// read the qport out of the message so we can fix up
	// stupid address translating routers
	MSG_BeginReadingOOB( msg );
	MSG_ReadLong( msg );				// sequence number
	qport = MSG_ReadShort( msg ) & 0xffff;

	// find which client the message is from
	for (i=0, cl=svs.clients ; i < sv_maxclients->integer ; i++,cl++) {
		if (cl->state == CS_FREE) {
			continue;
		}
		if ( !NET_CompareBaseAdr( from, cl->netchan.remoteAddress ) ) {
			continue;
		}
		// it is possible to have multiple clients from a single IP
		// address, so they are differentiated by the qport variable
		if (cl->netchan.qport != qport) {
			continue;
		}

		// the IP port can't be used to differentiate them, because
		// some address translating routers periodically change UDP
		// port assignments
		if (cl->netchan.remoteAddress.port != from.port) {
			Com_Printf( "SV_PacketEvent: fixing up a translated port\n" );
			cl->netchan.remoteAddress.port = from.port;
		}

		// make sure it is a valid, in sequence packet
		if (SV_Netchan_Process(cl, msg)) {
			// zombie clients still need to do the Netchan_Process
			// to make sure they don't need to retransmit the final
			// reliable message, but they don't do any other processing
			if (cl->state != CS_ZOMBIE) {
				cl->lastPacketTime = svs.time;	// don't timeout
				SV_ExecuteClientMessage( cl, msg );
			}
		}
		return;
	}
	
	// if we received a sequenced packet from an address we don't recognize,
	// send an out of band disconnect packet to it
	NET_OutOfBandPrint( NS_SERVER, from, "disconnect" );
}


/*
===================
SV_CalcPings

Updates the cl->ping variables
===================
*/
void SV_CalcPings( void ) {
	int			i, j;
	client_t	*cl;
	int			total, count;
	int			delta;
	playerState_t	*ps;

	for (i=0 ; i < sv_maxclients->integer ; i++) {
		cl = &svs.clients[i];
		if ( cl->state != CS_ACTIVE ) {
			cl->ping = 999;
			continue;
		}
		if ( !cl->gentity ) {
			cl->ping = 999;
			continue;
		}
		if ( cl->gentity->r.svFlags & SVF_BOT ) {
			cl->ping = 0;
			continue;
		}

		total = 0;
		count = 0;
		for ( j = 0 ; j < PACKET_BACKUP ; j++ ) {
			if ( cl->frames[j].messageAcked <= 0 ) {
				continue;
			}
			delta = cl->frames[j].messageAcked - cl->frames[j].messageSent;
			count++;
			total += delta;
		}
		if (!count) {
			cl->ping = 999;
		} else {
			cl->ping = total/count;
			if ( cl->ping > 999 ) {
				cl->ping = 999;
			}
		}

		// let the game dll know about the ping
		ps = SV_GameClientNum( i );
		ps->ping = cl->ping;
	}
}

/*
==================
SV_CheckTimeouts

If a packet has not been received from a client for timeout->integer 
seconds, drop the conneciton.  Server time is used instead of
realtime to avoid dropping the local client while debugging.

When a client is normally dropped, the client_t goes into a zombie state
for a few seconds to make sure any final reliable message gets resent
if necessary
==================
*/
void SV_CheckTimeouts( void ) {
	int		i;
	client_t	*cl;
	int			droppoint;
	int			zombiepoint;

	droppoint = svs.time - 1000 * sv_timeout->integer;
	zombiepoint = svs.time - 1000 * sv_zombietime->integer;

	for (i=0,cl=svs.clients ; i < sv_maxclients->integer ; i++,cl++) {
		// message times may be wrong across a changelevel
		if (cl->lastPacketTime > svs.time) {
			cl->lastPacketTime = svs.time;
		}

		if (cl->state == CS_ZOMBIE
		&& cl->lastPacketTime < zombiepoint) {
			// using the client id cause the cl->name is empty at this point
			Com_DPrintf( "Going from CS_ZOMBIE to CS_FREE for client %d\n", i );
			cl->state = CS_FREE;	// can now be reused
			continue;
		}
		if ( cl->state >= CS_CONNECTED && cl->lastPacketTime < droppoint) {
			// wait several frames so a debugger session doesn't
			// cause a timeout
			if ( ++cl->timeoutCount > 5 ) {
				SV_DropClient (cl, "timed out"); 
				cl->state = CS_FREE;	// don't bother with zombie state
			}
		} else {
			cl->timeoutCount = 0;
		}
	}
}


/*
==================
SV_CheckPaused
==================
*/
qboolean SV_CheckPaused( void ) {
	int		count;
	client_t	*cl;
	int		i;

	if ( !cl_paused->integer ) {
		return qfalse;
	}

	// only pause if there is just a single client connected
	count = 0;
	for (i=0,cl=svs.clients ; i < sv_maxclients->integer ; i++,cl++) {
		if ( cl->state >= CS_CONNECTED && cl->netchan.remoteAddress.type != NA_BOT ) {
			count++;
		}
	}

	if ( count > 1 ) {
		// don't pause
		if (sv_paused->integer)
			Cvar_Set("sv_paused", "0");
		return qfalse;
	}

	if (!sv_paused->integer)
		Cvar_Set("sv_paused", "1");
	return qtrue;
}

/*
==================
SV_Frame

Player movement occurs as a result of packet events, which
happen before SV_Frame is called
==================
*/
void SV_Frame( int msec ) {
	int		frameMsec;
	int		startTime;

	// the menu kills the server with this cvar
	if ( sv_killserver->integer ) {
		SV_Shutdown ("Server was killed.\n");
		Cvar_Set( "sv_killserver", "0" );
		return;
	}

	if ( !com_sv_running->integer ) {
		return;
	}

	// allow pause if only the local client is connected
	if ( SV_CheckPaused() ) {
		return;
	}

	// if it isn't time for the next frame, do nothing
	if ( sv_fps->integer < 1 ) {
		Cvar_Set( "sv_fps", "10" );
	}
	frameMsec = 1000 / sv_fps->integer ;

	sv.timeResidual += msec;

	if (!com_dedicated->integer) SV_BotFrame( svs.time + sv.timeResidual );

	if ( com_dedicated->integer && sv.timeResidual < frameMsec ) {
		// NET_Sleep will give the OS time slices until either get a packet
		// or time enough for a server frame has gone by
		NET_Sleep(frameMsec - sv.timeResidual);
		return;
	}

	// if time is about to hit the 32nd bit, kick all clients
	// and clear sv.time, rather
	// than checking for negative time wraparound everywhere.
	// 2giga-milliseconds = 23 days, so it won't be too often
	if ( svs.time > 0x70000000 ) {
		SV_Shutdown( "Restarting server due to time wrapping" );
		Cbuf_AddText( "vstr nextmap\n" );
		return;
	}
	// this can happen considerably earlier when lots of clients play and the map doesn't change
	if ( svs.nextSnapshotEntities >= 0x7FFFFFFE - svs.numSnapshotEntities ) {
		SV_Shutdown( "Restarting server due to numSnapshotEntities wrapping" );
		Cbuf_AddText( "vstr nextmap\n" );
		return;
	}

	if( sv.restartTime && svs.time >= sv.restartTime ) {
		sv.restartTime = 0;
		Cbuf_AddText( "map_restart 0\n" );
		return;
	}

	// update infostrings if anything has been changed
	if ( cvar_modifiedFlags & CVAR_SERVERINFO ) {
		SV_SetConfigstring( CS_SERVERINFO, Cvar_InfoString( CVAR_SERVERINFO ) );
		cvar_modifiedFlags &= ~CVAR_SERVERINFO;
	}
	if ( cvar_modifiedFlags & CVAR_SYSTEMINFO ) {
		SV_SetConfigstring( CS_SYSTEMINFO, Cvar_InfoString_Big( CVAR_SYSTEMINFO ) );
		cvar_modifiedFlags &= ~CVAR_SYSTEMINFO;
	}

	if ( com_speeds->integer ) {
		startTime = Sys_Milliseconds ();
	} else {
		startTime = 0;	// quite a compiler warning
	}

	// update ping based on the all received frames
	SV_CalcPings();

	if (com_dedicated->integer) SV_BotFrame( svs.time );

	// run the game simulation in chunks
	while ( sv.timeResidual >= frameMsec ) {
		sv.timeResidual -= frameMsec;
		svs.time += frameMsec;

		// let everything in the world think and move
		VM_Call( gvm, GAME_RUN_FRAME, svs.time );
	}

	if ( com_speeds->integer ) {
		time_game = Sys_Milliseconds () - startTime;
	}

	// check timeouts
	SV_CheckTimeouts();

	// send messages back to the clients
	SV_SendClientMessages();

	// send a heartbeat to the master if needed
	SV_MasterHeartbeat();
}

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