cl_parse.c

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	const char		*s, *t;
	char			key[BIG_INFO_KEY];
	char			value[BIG_INFO_VALUE];
	qboolean		gameSet;

	systemInfo = cl.gameState.stringData + cl.gameState.stringOffsets[ CS_SYSTEMINFO ];
	// NOTE TTimo:
	// when the serverId changes, any further messages we send to the server will use this new serverId
	// https://zerowing.idsoftware.com/bugzilla/show_bug.cgi?id=475
	// in some cases, outdated cp commands might get sent with this news serverId
	cl.serverId = atoi( Info_ValueForKey( systemInfo, "sv_serverid" ) );

	// don't set any vars when playing a demo
	if ( clc.demoplaying ) {
		return;
	}

	s = Info_ValueForKey( systemInfo, "sv_cheats" );
	if ( atoi(s) == 0 ) {
		Cvar_SetCheatState();
	}

	// check pure server string
	s = Info_ValueForKey( systemInfo, "sv_paks" );
	t = Info_ValueForKey( systemInfo, "sv_pakNames" );
	FS_PureServerSetLoadedPaks( s, t );

	s = Info_ValueForKey( systemInfo, "sv_referencedPaks" );
	t = Info_ValueForKey( systemInfo, "sv_referencedPakNames" );
	FS_PureServerSetReferencedPaks( s, t );

	gameSet = qfalse;
	// scan through all the variables in the systeminfo and locally set cvars to match
	s = systemInfo;
	while ( s ) {
		Info_NextPair( &s, key, value );
		if ( !key[0] ) {
			break;
		}
		// ehw!
		if ( !Q_stricmp( key, "fs_game" ) ) {
			gameSet = qtrue;
		}

		Cvar_Set( key, value );
	}
	// if game folder should not be set and it is set at the client side
	if ( !gameSet && *Cvar_VariableString("fs_game") ) {
		Cvar_Set( "fs_game", "" );
	}
	cl_connectedToPureServer = Cvar_VariableValue( "sv_pure" );
}

/*
==================
CL_ParseGamestate
==================
*/
void CL_ParseGamestate( msg_t *msg ) {
	int				i;
	entityState_t	*es;
	int				newnum;
	entityState_t	nullstate;
	int				cmd;
	char			*s;

	Con_Close();

	clc.connectPacketCount = 0;

	// wipe local client state
	CL_ClearState();

	// a gamestate always marks a server command sequence
	clc.serverCommandSequence = MSG_ReadLong( msg );

	// parse all the configstrings and baselines
	cl.gameState.dataCount = 1;	// leave a 0 at the beginning for uninitialized configstrings
	while ( 1 ) {
		cmd = MSG_ReadByte( msg );

		if ( cmd == svc_EOF ) {
			break;
		}
		
		if ( cmd == svc_configstring ) {
			int		len;

			i = MSG_ReadShort( msg );
			if ( i < 0 || i >= MAX_CONFIGSTRINGS ) {
				Com_Error( ERR_DROP, "configstring > MAX_CONFIGSTRINGS" );
			}
			s = MSG_ReadBigString( msg );
			len = strlen( s );

			if ( len + 1 + cl.gameState.dataCount > MAX_GAMESTATE_CHARS ) {
				Com_Error( ERR_DROP, "MAX_GAMESTATE_CHARS exceeded" );
			}

			// append it to the gameState string buffer
			cl.gameState.stringOffsets[ i ] = cl.gameState.dataCount;
			Com_Memcpy( cl.gameState.stringData + cl.gameState.dataCount, s, len + 1 );
			cl.gameState.dataCount += len + 1;
		} else if ( cmd == svc_baseline ) {
			newnum = MSG_ReadBits( msg, GENTITYNUM_BITS );
			if ( newnum < 0 || newnum >= MAX_GENTITIES ) {
				Com_Error( ERR_DROP, "Baseline number out of range: %i", newnum );
			}
			Com_Memset (&nullstate, 0, sizeof(nullstate));
			es = &cl.entityBaselines[ newnum ];
			MSG_ReadDeltaEntity( msg, &nullstate, es, newnum );
		} else {
			Com_Error( ERR_DROP, "CL_ParseGamestate: bad command byte" );
		}
	}

	clc.clientNum = MSG_ReadLong(msg);
	// read the checksum feed
	clc.checksumFeed = MSG_ReadLong( msg );

	// parse serverId and other cvars
	CL_SystemInfoChanged();

	// reinitialize the filesystem if the game directory has changed
  FS_ConditionalRestart( clc.checksumFeed );

	// This used to call CL_StartHunkUsers, but now we enter the download state before loading the
	// cgame
	CL_InitDownloads();

	// make sure the game starts
	Cvar_Set( "cl_paused", "0" );
}


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

/*
=====================
CL_ParseDownload

A download message has been received from the server
=====================
*/
void CL_ParseDownload ( msg_t *msg ) {
	int		size;
	unsigned char data[MAX_MSGLEN];
	int block;

	// read the data
	block = MSG_ReadShort ( msg );

	if ( !block )
	{
		// block zero is special, contains file size
		clc.downloadSize = MSG_ReadLong ( msg );

		Cvar_SetValue( "cl_downloadSize", clc.downloadSize );

		if (clc.downloadSize < 0)
		{
			Com_Error(ERR_DROP, MSG_ReadString( msg ) );
			return;
		}
	}

	size = MSG_ReadShort ( msg );
	if (size > 0)
		MSG_ReadData( msg, data, size );

	if (clc.downloadBlock != block) {
		Com_DPrintf( "CL_ParseDownload: Expected block %d, got %d\n", clc.downloadBlock, block);
		return;
	}

	// open the file if not opened yet
	if (!clc.download)
	{
		if (!*clc.downloadTempName) {
			Com_Printf("Server sending download, but no download was requested\n");
			CL_AddReliableCommand( "stopdl" );
			return;
		}

		clc.download = FS_SV_FOpenFileWrite( clc.downloadTempName );

		if (!clc.download) {
			Com_Printf( "Could not create %s\n", clc.downloadTempName );
			CL_AddReliableCommand( "stopdl" );
			CL_NextDownload();
			return;
		}
	}

	if (size)
		FS_Write( data, size, clc.download );

	CL_AddReliableCommand( va("nextdl %d", clc.downloadBlock) );
	clc.downloadBlock++;

	clc.downloadCount += size;

	// So UI gets access to it
	Cvar_SetValue( "cl_downloadCount", clc.downloadCount );

	if (!size) { // A zero length block means EOF
		if (clc.download) {
			FS_FCloseFile( clc.download );
			clc.download = 0;

			// rename the file
			FS_SV_Rename ( clc.downloadTempName, clc.downloadName );
		}
		*clc.downloadTempName = *clc.downloadName = 0;
		Cvar_Set( "cl_downloadName", "" );

		// send intentions now
		// We need this because without it, we would hold the last nextdl and then start
		// loading right away.  If we take a while to load, the server is happily trying
		// to send us that last block over and over.
		// Write it twice to help make sure we acknowledge the download
		CL_WritePacket();
		CL_WritePacket();

		// get another file if needed
		CL_NextDownload ();
	}
}

/*
=====================
CL_ParseCommandString

Command strings are just saved off until cgame asks for them
when it transitions a snapshot
=====================
*/
void CL_ParseCommandString( msg_t *msg ) {
	char	*s;
	int		seq;
	int		index;

	seq = MSG_ReadLong( msg );
	s = MSG_ReadString( msg );

	// see if we have already executed stored it off
	if ( clc.serverCommandSequence >= seq ) {
		return;
	}
	clc.serverCommandSequence = seq;

	index = seq & (MAX_RELIABLE_COMMANDS-1);
	Q_strncpyz( clc.serverCommands[ index ], s, sizeof( clc.serverCommands[ index ] ) );
}


/*
=====================
CL_ParseServerMessage
=====================
*/
void CL_ParseServerMessage( msg_t *msg ) {
	int			cmd;

	if ( cl_shownet->integer == 1 ) {
		Com_Printf ("%i ",msg->cursize);
	} else if ( cl_shownet->integer >= 2 ) {
		Com_Printf ("------------------\n");
	}

	MSG_Bitstream(msg);

	// get the reliable sequence acknowledge number
	clc.reliableAcknowledge = MSG_ReadLong( msg );
	// 
	if ( clc.reliableAcknowledge < clc.reliableSequence - MAX_RELIABLE_COMMANDS ) {
		clc.reliableAcknowledge = clc.reliableSequence;
	}

	//
	// parse the message
	//
	while ( 1 ) {
		if ( msg->readcount > msg->cursize ) {
			Com_Error (ERR_DROP,"CL_ParseServerMessage: read past end of server message");
			break;
		}

		cmd = MSG_ReadByte( msg );

		if ( cmd == svc_EOF) {
			SHOWNET( msg, "END OF MESSAGE" );
			break;
		}

		if ( cl_shownet->integer >= 2 ) {
			if ( !svc_strings[cmd] ) {
				Com_Printf( "%3i:BAD CMD %i\n", msg->readcount-1, cmd );
			} else {
				SHOWNET( msg, svc_strings[cmd] );
			}
		}
	
	// other commands
		switch ( cmd ) {
		default:
			Com_Error (ERR_DROP,"CL_ParseServerMessage: Illegible server message\n");
			break;			
		case svc_nop:
			break;
		case svc_serverCommand:
			CL_ParseCommandString( msg );
			break;
		case svc_gamestate:
			CL_ParseGamestate( msg );
			break;
		case svc_snapshot:
			CL_ParseSnapshot( msg );
			break;
		case svc_download:
			CL_ParseDownload( msg );
			break;
		}
	}
}