FRollingHash Class Reference

#include <BuildPatchHash.h>

Public Member Functions
	FRollingHash (uint32 WindowSize)
void	ConsumeByte (const uint8 &NewByte)
void	ConsumeBytes (const uint8 *NewBytes, const uint32 &NumBytes)
void	RollForward (const uint8 &NewByte)
void	Clear ()
const uint64	GetWindowHash () const
const HashRingBuffer &	GetWindowData () const
const uint32	GetNumDataNeeded () const
const uint32	GetWindowSize () const

Static Public Member Functions
static uint64	GetHashForDataSet (const uint8 *DataSet, uint32 WindowSize)

Detailed Description

A class that performs a rolling hash

Constructor & Destructor Documentation

FRollingHash()

FRollingHash::FRollingHash

(

uint32

WindowSize

)

Constructor

Member Function Documentation

Clear()

void FRollingHash::Clear

(

)

Clears all data ready for a new entire data set

ConsumeByte()

void FRollingHash::ConsumeByte

(

const uint8 &

NewByte

)

Pass this function the initial data set to start the Rolling Hash with.

Parameters

NewByte

The byte to add to the hash state

ConsumeBytes()

void FRollingHash::ConsumeBytes	(	const uint8 *	NewBytes,
		const uint32 &	NumBytes
	)

Helper to consume from a byte array

Parameters

NewBytes	The byte array
NumBytes	The number of bytes to consume

GetHashForDataSet()

uint64 FRollingHash::GetHashForDataSet ( const uint8 *  DataSet, uint32  WindowSize  )

static

Static function to simply return the hash for a given data range.

Parameters

DataSet	The buffer to the data.
WindowSize	The buffer of length.

Returns

The hash state for the provided data

GetNumDataNeeded()

const uint32 FRollingHash::GetNumDataNeeded

(

)

const

Get how many DataValueType values we still need to consume until our window is full

Returns

The number of DataValueType we still need

GetWindowData()

const TRingBuffer< uint8 > & FRollingHash::GetWindowData

(

)

const

Get the Ring Buffer for the current window

Returns

The ring buffer

GetWindowHash()

const uint64 FRollingHash::GetWindowHash

(

)

const

Get the HashState for the current window

Returns

The hash state

GetWindowSize()

const uint32 FRollingHash::GetWindowSize

(

)

const

Returns

the size of our window

RollForward()

void FRollingHash::RollForward

(

const uint8 &

NewByte

)

Rolls the window by one byte forwards.

Parameters

NewByte

The byte that will be added to the front of the window

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

• Engine/Source/Runtime/Online/BuildPatchServices/Private/BuildPatchHash.h
• Engine/Source/Runtime/Online/BuildPatchServices/Private/BuildPatchHash.cpp