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khanat-opennel-code/code/ryzom/client/src/network_connection.h

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// Ryzom - MMORPG Framework <http://dev.ryzom.com/projects/ryzom/>
// Copyright (C) 2010 Winch Gate Property Limited
//
// This program is free software: you can redistribute it and/or modify
// it under the terms of the GNU Affero General Public License as
// published by the Free Software Foundation, either version 3 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 Affero General Public License for more details.
//
// You should have received a copy of the GNU Affero General Public License
// along with this program. If not, see <http://www.gnu.org/licenses/>.
#ifndef NL_NETWORK_CONNECTION_H
#define NL_NETWORK_CONNECTION_H
#include "nel/misc/types_nl.h"
#include "nel/misc/bit_set.h"
#include <string>
#include <vector>
#include <list>
#include <deque>
#include <set>
#include <nel/misc/bit_mem_stream.h>
#include <nel/net/inet_address.h>
#include <nel/net/login_cookie.h>
#include <nel/net/login_client.h>
#include <nel/net/udp_sim_sock.h>
#include <nel/misc/vectord.h>
#include <nel/misc/md5.h>
#include "time_client.h"
#include "game_share/entity_types.h"
#include "property_decoder.h"
#include "impulse_decoder.h"
#include "game_share/action.h"
#include "game_share/ryzom_entity_id.h"
#include "game_share/action_block.h"
#include "game_share/loot_harvest_state.h"
/*
* ENABLE_INCOMING_MSG_RECORDER for recording/replaying incoming network messages
*/
#undef ENABLE_INCOMING_MSG_RECORDER
#ifdef ENABLE_INCOMING_MSG_RECORDER
#include <nel/misc/file.h>
#endif
/*
// UNUSED
const uint PropertiesPerEntity = 16;
const uint EntitiesPerClient = 256;
*/
namespace NLMISC{
class CCDBNodeBranch;
}
namespace CLFECOMMON
{
class CActionGeneric;
class CActionGenericMultiPart;
}
// Hierarchical timer
H_AUTO_DECL ( RZ_Client_Network_Connection_Set_Reference_Position )
//#define MEASURE_FE_SENDING
extern const char * ConnectionStateCStr [9];
/**
* Exception thrown when the sending returns a "blocking operation interrupted".
*/
class EBlockedByFirewall : public NLNET::ESocket
{};
struct TNewEntityInfo
{
void reset()
{
DataSetIndex = CLFECOMMON::INVALID_CLIENT_DATASET_INDEX;
Alias = 0;
}
/// Compressed dataset row
CLFECOMMON::TClientDataSetIndex DataSetIndex;
/// Alias (only for mission giver NPCs)
uint32 Alias;
};
// ***************************************************************************
/**
* Abstracts the connection client towards front-end
* \author Benjamin Legros, Olivier Cado
* \author Nevrax France
* \date 2001-2002
*/
class CNetworkConnection
{
public:
enum
{
/*
* DO LEAVE ENOUGH ROOM FOR FUTURE PROPERTIES !
*/
AddNewEntity = 32,
RemoveOldEntity,
ConnectionReady,
LagDetected,
ProbeReceived
};
struct TVPNodeClient : public CLFECOMMON::TVPNodeBase
{
struct TSlotContext
{
CNetworkConnection *NetworkConnection;
CLFECOMMON::TCLEntityId Slot;
NLMISC::TGameCycle Timestamp;
};
// Static data
static TSlotContext SlotContext;
///
TVPNodeClient() : TVPNodeBase() {}
TVPNodeClient *a() { return (TVPNodeClient*)VPA; }
TVPNodeClient *b() { return (TVPNodeClient*)VPB; }
TVPNodeClient *parent() { return (TVPNodeClient*)VPParent; }
///
void decodeDiscreetProperties( NLMISC::CBitMemStream& msgin )
{
msgin.serialBitAndLog( BranchHasPayload );
if ( BranchHasPayload )
{
if ( isLeaf() )
{
SlotContext.NetworkConnection->decodeDiscreetProperty( msgin, PropIndex );
}
else
{
if ( a() ) a()->decodeDiscreetProperties( msgin );
if ( b() ) b()->decodeDiscreetProperties( msgin );
}
}
}
void makeChildren()
{
VPA = new TVPNodeClient();
VPA->VPParent = this;
VPB = new TVPNodeClient();
VPB->VPParent = this;
}
void makeDescendants( uint nbLevels )
{
makeChildren();
if ( nbLevels > 1 )
{
a()->makeDescendants( nbLevels-1 );
b()->makeDescendants( nbLevels-1 );
}
}
void deleteBranches()
{
if ( a() )
{ a()->deleteBranches();
delete a();
}
if ( b() )
{ b()->deleteBranches();
delete b();
}
}
void deleteA()
{
if ( a() )
{ a()->deleteBranches();
delete a();
}
}
void deleteB()
{
if ( b() )
{ b()->deleteBranches();
delete b();
}
}
};
/// Additional info for position updates
struct TPositionInfo
{
/**
* Only for positions (property index 0): interval, in game cycle unit, between the current
* position update and the next predicted one. In most cases the next real position update
* will occur just before the predicted interval elapses.
*
* If the interval cannot be predicted yet (e.g. before having received two updates
* for the same entity), PredictedInterval is set to ~0.
*/
NLMISC::TGameCycle PredictedInterval;
/// Is position interior (only for position)
bool IsInterior;
};
/**
* A property change
*/
class CChange
{
public:
/// Constructor
CChange( CLFECOMMON::TCLEntityId id = 0, uint8 prop = 255, NLMISC::TGameCycle gc = 0 ) :
ShortId(id), Property(prop), GameCycle(gc) {}
/// Slot
CLFECOMMON::TCLEntityId ShortId;
/// Property index
uint8 Property;
/// The tick when the property changed, in server time
NLMISC::TGameCycle GameCycle;
// These contextual additional properties must be set by hand (not by constructor)
union
{
/// Position additional information (prediction & interior)
TPositionInfo PositionInfo;
/// Additional information when creating an entitys
TNewEntityInfo NewEntityInfo;
};
};
/// The states of the connection to the server (if you change them, change ConnectionStateCStr)
enum TConnectionState
{
NotInitialised = 0, // nothing happened yet
NotConnected, // init() called
Authenticate, // connect() called, identified by the login server
Login, // connecting to the frontend, sending identification
Synchronize, // connection accepted by the frontend, synchronizing
Connected, // synchronized, connected, ready to work
Probe, // connection lost by frontend, probing for response
Stalled, // server is stalled
Disconnect, // disconnect() called, or timeout, or connection closed by frontend
Quit // quit() called
};
typedef void (*TImpulseCallback)(NLMISC::CBitMemStream &, CLFECOMMON::TPacketNumber packet, void *arg);
static bool LoggingMode;
public:
/// Constructor
CNetworkConnection();
/// Destructor
virtual ~CNetworkConnection();
/// @name Connection initialisation
//@{
/**
* Inits the client connection to the front-end.
* \param cookie it s the cookie in string format that was passed to the exe command line (given by the nel_launcher)
* \param addr it s the front end address in string format that was passed to the exe command line (given by the nel_launcher)
*/
void init(const std::string &cookie, const std::string &addr);
/**
* Sets the cookie and front-end address, resets the connection state.
*/
void initCookie(const std::string &cookie, const std::string &addr);
/**
* Connects to the front-end (using or not the login system, depending on what was specified at init())
* \param result the message returned in case of an error
* Returns true if no error occured.
*/
bool connect(std::string &result);
/**
* Sets the callback called when a generic impulse comes
*/
void setImpulseCallback(TImpulseCallback callback, void *argument = NULL);
//@}
/// @name Connection management
//@{
/**
* Tells if the client is yet connected or not
*/
bool isConnected();
/**
* Gets the connection state
*/
TConnectionState getConnectionState() const { return _ConnectionState; }
/**
* Updates the whole connection with the frontend.
*
* Behaviour in login state when a firewall does not grant the sending:
* - When a sending is refused (error "Blocking operation interrupted")
* the exception EBlockedByFirewall in thrown. The first time, a time-out is armed.
* - In a later attempt, if the time-out expired, the function sets state to
* Disconnect, then throws EBlockedByFirewall.
*
* \return bool 'true' if data were sent/received.
*/
bool update();
/**
* Disconnects the current connection
*/
void disconnect();
//@}
/**
* Quit the game till the connection is reset
*/
void quit();
/// @name Database management
//@{
/**
* Set database entry point
*/
void setDataBase(NLMISC::CCDBNodeBranch *database);
//@}
/// @name Push and Send
//@{
/**
* Buffers a bitmemstream, that will be converted into a generic action, to be sent later to the server (at next update).
*/
void push (NLMISC::CBitMemStream &msg);
/**
* Buffers an action to be sent at next update (or later updates if network overload occurs)
*/
void push(CLFECOMMON::CAction *action);
/**
* Buffers a target action (set targetOrPickup to true for target, false for pick-up
*/
void pushTarget(CLFECOMMON::TCLEntityId slot, LHSTATE::TLHState targetOrPickup);
/**
* Send
*/
void send(NLMISC::TGameCycle);
/**
* Send last information without changes (only acknowedges frontend)
*/
void send();
/**
* Clear not acknownledged actions in sending buffer
*/
void flushSendBuffer() { _Actions.clear(); }
/**
* Set player reference position
*/
// void setReferencePosition(const NLMISC::CVectorD &position) { _ImpulseDecoder.setReferencePosition(position); }
//@}
/// @name Temp methods
// @{
const std::vector<CChange> &getChanges() { return _Changes; }
void clearChanges() { _Changes.clear(); }
// @}
/// @name Client time hints
// @{
NLMISC::TTime getCurrentClientTime() { return _CurrentClientTime; } // the time currently played at this frame (in the past)
NLMISC::TGameCycle getCurrentClientTick() { return _CurrentClientTick; } // the tick for the current frame (also in the past)
NLMISC::TGameCycle getCurrentServerTick() { return _CurrentServerTick; } // the last tick sent by the server.
NLMISC::TTime getMachineTimeAtTick() { return _MachineTimeAtTick; } // the machine time at the beginning of the current tick
NLMISC::TTicks getMachineTicksAtTick() { return _MachineTicksAtTick; }
sint32 getMsPerTick() { return _MsPerTick; }
NLMISC::TGameCycle getSynchronize() { return _Synchronize; }
uint32 getBestPing() { return _BestPing; }
uint32 getPing() const { return _InstantPing; }
NLMISC::TTime getLCT() { return _LCT; } // Lag compensation time
NLMISC::TTime getUpdateTime() { return _UpdateTime; }
NLMISC::TTicks getUpdateTicks() { return _UpdateTicks; }
// Return an estimated smooth server tick. Increment only and accelerate/decelerate according to network
sint64 getCurrentSmoothServerTick() const { return _CurrentSmoothServerTick; }
// Convert a GameCycle to a SmoothServerTick
sint64 convertToSmoothServerTick(NLMISC::TGameCycle t) const;
// @}
/// Set the Lag Compensation Time in ms (default: 1000)
void setLCT( NLMISC::TTime lct ) { _LCT = lct; }
/// Allocation statistics
void displayAllocationStats();
/// Get Allocation statistics
std::string getAllocationStats();
/// @name Network Stats Methods
// @{
uint32 getSentBytes() { return _TotalSentBytes; }
uint32 getPartialSentBytes() { uint32 ret = _PartialSentBytes; _PartialSentBytes = 0; return ret; }
uint32 getReceivedBytes() { return _TotalReceivedBytes; }
uint32 getPartialReceivedBytes() { uint32 ret = _PartialReceivedBytes; _PartialReceivedBytes = 0; return ret; }
bool getConnectionQuality() { return _ConnectionQuality; }
NLMISC::TTime getTimeSinceLastReceivedPacket() { return NLMISC::CTime::getLocalTime()-_LastReceivedNormalTime; }
/// Return the average billed download rate in kbps, including all headers (UDP+IP+Ethernet)
float getMeanDownload() { return (_MeanDownload.mean(ryzomGetLocalTime ())+20+8+14)*0.008f; }
/// Return the average billed upload rate in kbps, including all headers (UDP+IP+Ethernet)
float getMeanUpload() { return (_MeanUpload.mean(ryzomGetLocalTime ())+20+8+14)*0.008f; }
/// Return the packet loss average
float getMeanPacketLoss()
{
NLMISC::TTime time = ryzomGetLocalTime ();
_MeanPackets.check(time);
_MeanLoss.check(time);
float dpk = _MeanPackets.Values.empty() ? 0.0f : _MeanPackets.Values.back().second-_MeanPackets.Values.front().second+1;
float tloss = _MeanLoss.Content;
return (dpk > 0.0f) ? std::min(100.0f, tloss*100.0f/dpk) : 0.0f;
}
/// Get total lost packets
uint32 getTotalLostPackets() const { return _TotalLostPackets; }
// @}
/// Get the NLMISC::CEntityId from the TCLEntityId
CLFECOMMON::TSheetId get(CLFECOMMON::TCLEntityId id) const { return _PropertyDecoder.sheet(id); }
/// Get the TCLEntityId from the NLMISC::CEntityId
sint get(CLFECOMMON::TSheetId id) const
{
TIdMap::const_iterator it = _IdMap.find(id);
return (it != _IdMap.end()) ? (*it).second : -1;
}
/// Set player's reference position
void setReferencePosition(const NLMISC::CVectorD &position)
{
H_AUTO_USE ( RZ_Client_Network_Connection_Set_Reference_Position )
_PropertyDecoder.setReferencePosition( position );
}
/// Get local IP address
const NLNET::CInetAddress& getAddress()
{
return _Connection.localAddr();
}
/// Get socket
NLNET::CUdpSock& getConnection()
{
return _Connection.UdpSock;
}
/// Get userId
uint32 getUserId()
{
if(_LoginCookie.isValid())
return _LoginCookie.getUserId();
else
return 0xFFFFFFFF;
}
/// Get connection state c_string
const char * getConnectionStateCStr()
{
return ConnectionStateCStr[_ConnectionState];
}
/// Return the login cookie
const NLNET::CLoginCookie& getLoginCookie() const
{
return _LoginCookie;
}
#ifdef ENABLE_INCOMING_MSG_RECORDER
/// Return 'true' if currently recording.
bool isRecording() const {return _RecordIncomingMessagesOn;}
/// Return 'true' if currently replaying.
bool isReplaying() const {return _ReplayIncomingMessagesOn;}
/// Start/stop recording the incoming messages (in online mode)
void setRecordingMode( bool onOff, const std::string& filename = "");
/// Start/stop replaying the incoming messages (in offline mode)
void setReplayingMode( bool onOff, const std::string& filename = "");
#endif
void decodeDiscreetProperty( NLMISC::CBitMemStream& msgin, CLFECOMMON::TPropIndex propIndex );
const std::string &getFrontendAddress() { return _FrontendAddress; }
protected:
/// The current state of the connection
TConnectionState _ConnectionState;
/// Connection Quality check
bool _ConnectionQuality;
/// The address of the frontend service
std::string _FrontendAddress;
/// The cookie for the login service
NLNET::CLoginCookie _LoginCookie;
/// The UDP connection to the frontend
NLNET::CUdpSimSock _Connection;
/// The receive buffer
uint32 _ReceiveBuffer[65536];
/// The impulse decoder
CImpulseDecoder _ImpulseDecoder;
/// The callback for generic actions
TImpulseCallback _ImpulseCallback;
/// The callback argument
void *_ImpulseArg;
/// Position update tick queues (used for statistical interval prediction), one per slot
std::deque<NLMISC::TGameCycle> _PosUpdateTicks[256];
/// Position update interval sorted sets (used for statistical interval prediction), one per slot
std::multiset<NLMISC::TGameCycle> _PosUpdateIntervals[256];
/// MD5 hash keys of msg.xml and database.xml
NLMISC::CHashKeyMD5 _MsgXmlMD5;
NLMISC::CHashKeyMD5 _DatabaseXmlMD5;
// if prec don't work, those may (if the server run on windows, prec won't work)
NLMISC::CHashKeyMD5 _AltMsgXmlMD5;
NLMISC::CHashKeyMD5 _AltDatabaseXmlMD5;
/// @name Network statistics
//@{
class CMeanComputer
{
public:
CMeanComputer() : MeanPeriod(2000), Content(0.0f) {}
std::deque< std::pair<NLMISC::TTime, float> > Values;
uint32 MeanPeriod; // in ms
float Content;
// checks all values have valid time (inside the mean period)
void check(NLMISC::TTime time)
{
while (!Values.empty() && Values.front().first < time-MeanPeriod)
{
Content -= Values.front().second;
Values.pop_front();
}
}
// updates the mean with a new value and time
void update(float value, NLMISC::TTime time)
{
if (!Values.empty() && Values.back().first > time)
return;
check(time);
Values.push_back(std::make_pair(time, value));
Content += value;
}
// gets the mean
float mean(NLMISC::TTime time)
{
check(time);
return Content*1000.0f/(float)MeanPeriod;
}
};
/// The total received length (from the beginning)
uint32 _TotalReceivedBytes;
/// The partial received length (since last read)
uint32 _PartialReceivedBytes;
/// The total sent length
uint32 _TotalSentBytes;
/// Partial sent length
uint32 _PartialSentBytes;
/// Total lost packets
uint32 _TotalLostPackets;
/// Mean download (payload bytes)
CMeanComputer _MeanDownload;
/// Mean upload (payload bytes)
CMeanComputer _MeanUpload;
/// Mean packets
CMeanComputer _MeanPackets;
/// Mean lost
CMeanComputer _MeanLoss;
//@}
/// The property decoder
CPropertyDecoder _PropertyDecoder;
/// The database entry
NLMISC::CCDBNodeBranch *_DataBase;
/// @name Header message decoding
//@{
/// Was the header decoded for the last received message?
bool _DecodedHeader;
/// The received number lastly decoded
CLFECOMMON::TPacketNumber _CurrentReceivedNumber;
/// The message is in system mode
bool _SystemMode;
/// Did we received a probe since last update
bool _ReceivedSync;
uint _TotalMessages;
//@}
/// @name Client and Server packet numbering management
//@{
CLFECOMMON::TPacketNumber _CurrentSendNumber; // number that will be used to send the next packet
CLFECOMMON::TPacketNumber _LastReceivedNumber; // number of the last packet receive from the server
uint32 _AckBitMask; // this mask contains ack of old messages received by the server
uint32 _LastAckBit; // a remember of the status of the previous received packet
NLMISC::TTime _LastReceivedTime; // last time the client received something from the server
NLMISC::CBitSet _LongAckBitField;
CLFECOMMON::TPacketNumber _LastAckInLongAck;
NLMISC::TGameCycle _LastSentCycle;
CLFECOMMON::TPacketNumber _LastReceivedPacketInBothModes;
NLMISC::TTime _LastReceivedNormalTime; // last time the client received valid normal message from the server
uint8 _ImpulseMultiPartNumber;
//@}
/// @name Client and Server time management
//@{
/// The stamps queues
typedef std::deque<std::pair<sint32, NLMISC::TTime> > TStampQueue;
// used for lag compensation
NLMISC::TTime _CurrentClientTime; // the time currently played at this frame (in the past)
NLMISC::TGameCycle _CurrentClientTick; // the tick for the current frame (also in the past)
NLMISC::TGameCycle _CurrentServerTick; // the last tick sent by the server.
NLMISC::TTime _MachineTimeAtTick; // the machine time at the beginning of the current tick
NLMISC::TTicks _MachineTicksAtTick;
sint32 _MsPerTick;
NLMISC::TGameCycle _Synchronize;
uint32 _BestPing;
uint32 _InstantPing;
NLMISC::TTime _LCT; // Lag compensation time
TStampQueue _PacketStamps;
NLMISC::TTime _UpdateTime;
NLMISC::TTicks _UpdateTicks;
NLMISC::TTime _LastSentSync;
NLMISC::TTime _LastSendTime;
//@}
std::list<CLFECOMMON::CActionBlock> _Actions;
/// Changes since
std::vector<CChange> _Changes;
// TEMP
uint32 _DummySend;
static bool _Registered;
/// @name Generic action multipart handling structures
//@{
struct CGenericMultiPartTemp
{
CGenericMultiPartTemp () : NbBlock(0xFFFFFFFF) { }
uint32 NbBlock;
uint32 NbCurrentBlock;
uint32 TempSize;
std::vector<std::vector<uint8> > Temp;
std::vector<bool> BlockReceived;
void set (CLFECOMMON::CActionGenericMultiPart *agmp, CNetworkConnection *parent);
};
std::vector<CGenericMultiPartTemp> _GenericMultiPartTemp;
//@}
/// @name NLMISC::CEntityId handling (for gamedev)
//@{
struct CHash
{
enum { bucket_size = 4, min_buckets = 8, };
size_t operator () (const CLFECOMMON::TSheetId &id) const { return id; }
inline bool operator() (const CLFECOMMON::TSheetId &id1, const CLFECOMMON::TSheetId &id2) const { return (size_t)id1 < (size_t)id2; }
};
typedef CHashMap<CLFECOMMON::TSheetId, CLFECOMMON::TCLEntityId, CHash> TIdMap;
TIdMap _IdMap;
//@}
TVPNodeClient *_VisualPropertyTreeRoot;
/// \name Smooth ServerTick mgt.
// @{
sint64 _CurrentSmoothServerTick;
NLMISC::TTime _SSTLastLocalTime;
void updateSmoothServerTick();
// @}
void reinit();
private:
/// Set MsPerTick value
void setMsPerTick(sint32 msPerTick);
/// Builds the CBitMemStream from the next incoming packet
bool buildStream(NLMISC::CBitMemStream &msgin);
/// @name Client automaton states and actions
//@{
//
void sendSystemLogin();
bool stateLogin();
NLMISC::TTime _LatestLoginTime;
//
void receiveSystemSync(NLMISC::CBitMemStream &msgin);
void sendSystemAckSync();
bool stateSynchronize();
NLMISC::TTime _LatestSyncTime;
uint32 _LatestSync;
//
void receiveNormalMessage(NLMISC::CBitMemStream &msgin);
void sendNormalMessage();
bool stateConnected();
CLFECOMMON::TPacketNumber _LastReceivedAck;
uint _NormalPacketsReceived;
//
void receiveSystemProbe(NLMISC::CBitMemStream &msgin);
void sendSystemAckProbe();
bool stateProbe();
std::vector<CLFECOMMON::TPacketNumber> _LatestProbes;
CLFECOMMON::TPacketNumber _LatestProbe;
NLMISC::TTime _LatestProbeTime;
//
void receiveSystemStalled(NLMISC::CBitMemStream &msgin);
bool stateStalled();
//
void sendSystemDisconnection();
//
bool stateQuit();
void receiveSystemAckQuit(NLMISC::CBitMemStream &msgin);
void sendSystemQuit();
uint32 _QuitId;
bool _ReceivedAckQuit;
NLMISC::TTime _LatestQuitTime;
//
void reset();
void initTicks();
//@}
//
bool decodeHeader(NLMISC::CBitMemStream &msgin, bool checkMessageNumber = true);
//
void buildSystemHeader(NLMISC::CBitMemStream &msgout);
//
void genericAction (CLFECOMMON::CActionGeneric *ag);
void genericAction (CLFECOMMON::CActionGenericMultiPart *agmp);
//
void statsSend(uint32 bytes);
void statsReceive(uint32 bytes);
bool associationBitsHaveChanged( CLFECOMMON::TCLEntityId slot, uint32 associationBits )
{
bool res = ((uint16)associationBits != _PropertyDecoder.associationBits( slot ));
_PropertyDecoder.associationBits( slot ) = (uint16)associationBits;
return res;
}
void decodeVisualProperties( NLMISC::CBitMemStream& msgin );
/// Return true if there is some messages to replay (in replay mode)
bool dataToReplayAvailable();
uint32 _AssociationBits;
#ifdef ENABLE_INCOMING_MSG_RECORDER
NLMISC::COFile _RecordedMessagesOut;
NLMISC::CIFile _RecordedMessagesIn;
NLMISC::TGameCycle _NextClientTickToReplay; // ~0 when no more message
NLMISC::CBitMemStream _NextMessageToReplay; // loaded at beginning of update(), read in buildStream()
bool _RecordIncomingMessagesOn;
bool _ReplayIncomingMessagesOn;
#endif
//
friend struct CGenericMultiPartTemp;
};
#endif // NL_NETWORK_CONNECTION_H
/* End of network_connection.h */
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