FNetPacketNotify Class Reference

#include <NetPacketNotify.h>

Classes
struct	FNotificationHeader

Public Types
enum	{ SequenceNumberBits = 14 }
enum	{ MaxSequenceHistoryLength = 256 }
typedef TSequenceNumber< SequenceNumberBits, uint16 >	SequenceNumberT
typedef TSequenceHistory< MaxSequenceHistoryLength >	SequenceHistoryT

Public Member Functions
	FNetPacketNotify ()
void	Init (SequenceNumberT InitialInSeq, SequenceNumberT InitialOutSeq)
void	AckSeq (SequenceNumberT Seq)
void	NakSeq (SequenceNumberT Seq)
SequenceNumberT	CommitAndIncrementOutSeq ()
bool	WriteHeader (FBitWriter &Writer, bool bRefresh=false)
bool	ReadHeader (FNotificationHeader &Data, FBitReader &Reader) const
SequenceNumberT::DifferenceT	GetSequenceDelta (const FNotificationHeader &NotificationData)
template<class Functor >
SequenceNumberT::DifferenceT	Update (const FNotificationHeader &NotificationData, Functor &&InFunc)
const SequenceHistoryT &	GetInSeqHistory () const
SequenceNumberT	GetInSeq () const
SequenceNumberT	GetInAckSeq () const
SequenceNumberT	GetOutSeq () const
SequenceNumberT	GetOutAckSeq () const
bool	CanSend () const
bool	IsSequenceWindowFull (uint32 SafetyMargin=0U) const
SequenceNumberT::DifferenceT	GetCurrentSequenceHistoryLength () const
bool	IsWaitingForSequenceHistoryFlush () const

Detailed Description

FNetPacketNotify - Drives delivery of sequence numbers, acknowledgments and notifications of delivery sequence numbers

Member Typedef Documentation

SequenceHistoryT

typedef TSequenceHistory<MaxSequenceHistoryLength> FNetPacketNotify::SequenceHistoryT

SequenceNumberT

typedef TSequenceNumber<SequenceNumberBits, uint16> FNetPacketNotify::SequenceNumberT

Member Enumeration Documentation

anonymous enum

anonymous enum

Enumerator
SequenceNumberBits

anonymous enum

anonymous enum

Enumerator
MaxSequenceHistoryLength

Constructor & Destructor Documentation

FNetPacketNotify()

FNetPacketNotify::FNetPacketNotify

(

)

Constructor

Member Function Documentation

AckSeq()

void FNetPacketNotify::AckSeq ( SequenceNumberT  Seq )

inline

Mark Seq as received and update current InSeq, missing sequence numbers will be marked as lost

CanSend()

bool FNetPacketNotify::CanSend ( ) const

inline

If we do have more unacknowledged sequence numbers in-flight than our maximum sendwindow we should not send more as the receiving end will not be able to detect if the sequence number has wrapped around

CommitAndIncrementOutSeq()

FNetPacketNotify::SequenceNumberT FNetPacketNotify::CommitAndIncrementOutSeq

(

)

Increment outgoing seq number and commit data

GetCurrentSequenceHistoryLength()

FNetPacketNotify::SequenceNumberT::DifferenceT FNetPacketNotify::GetCurrentSequenceHistoryLength

(

)

const

Get the current sequenceHistory length in bits, clamped to the maximum history length

GetInAckSeq()

SequenceNumberT FNetPacketNotify::GetInAckSeq ( ) const

inline

Get the last received sequence number that we have accepted, InAckSeq cannot be larger than InSeq

GetInSeq()

SequenceNumberT FNetPacketNotify::GetInSeq ( ) const

inline

Get the last received in sequence number

GetInSeqHistory()

const SequenceHistoryT & FNetPacketNotify::GetInSeqHistory ( ) const

inline

Get the current SequenceHistory

GetOutAckSeq()

SequenceNumberT FNetPacketNotify::GetOutAckSeq ( ) const

inline

Get the last outgoing sequence number acknowledged by remote

GetOutSeq()

SequenceNumberT FNetPacketNotify::GetOutSeq ( ) const

inline

Get the current outgoing sequence number

GetSequenceDelta()

SequenceNumberT::DifferenceT FNetPacketNotify::GetSequenceDelta ( const FNotificationHeader &  NotificationData )

inline

Gets the delta between the present sequence, and the sequence inside the specified header - if the delta is positive

Init()

void FNetPacketNotify::Init	(	SequenceNumberT	InitialInSeq,
		SequenceNumberT	InitialOutSeq
	)

Init notification with expected initial sequence numbers

IsSequenceWindowFull()

bool FNetPacketNotify::IsSequenceWindowFull ( uint32  SafetyMargin = 0U ) const

inline

Return whether we can send packets without exhausting the packet sequence history window, as it could cause packets to be NAKed even when they've been received by the remote peer.

Parameters

SafetyMargin

A small number representing how many packets you would like to keep as a safety margin for heart beats or other important packets.

IsWaitingForSequenceHistoryFlush()

bool FNetPacketNotify::IsWaitingForSequenceHistoryFlush ( ) const

inline

Returns true if we are currently waiting for a flush of the sequence window

NakSeq()

void FNetPacketNotify::NakSeq ( SequenceNumberT  Seq )

inline

Explicitly mark Seq as not received and update current InSeq, additional missing sequence numbers will be marked as lost

ReadHeader()

bool FNetPacketNotify::ReadHeader	(	FNotificationHeader &	Data,
		FBitReader &	Reader
	)		const

Read header from stream

Update()

template<class Functor >

FNetPacketNotify::SequenceNumberT::DifferenceT FNetPacketNotify::Update	(	const FNotificationHeader &	NotificationData,
		Functor &&	InFunc
	)

Update state of PacketNotification based on received header and invoke packet notifications for received acks.

Parameters

NotificationData	The header to update from
InFunc	A function in the format (void)(FNetPacketNotify::SequenceNumberT AckedSequence, bool bDelivered) to handle packet notifications.

Returns

The > 0 delta of the incoming seq if within half the seq number space. 0 if the received seq is outside current window ,or the ack seq received is invalid.

WriteHeader()

bool FNetPacketNotify::WriteHeader	(	FBitWriter &	Writer,
		bool	bRefresh = false
	)

Write NotificationHeader, and update outgoing ack record if bRefresh is true we will attempt to refresh a previously written header if the resulting size will be the same as the already written header. returns true if data was written, and false if no data was written which might be the case if we try to rewrite an existing header but the required size differs.

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The documentation for this class was generated from the following files:

• Engine/Source/Runtime/Engine/Public/Net/NetPacketNotify.h
• Engine/Source/Runtime/Engine/Private/Net/NetPacketNotify.cpp