FIoChunkEncoding Class Reference

#include <IoChunkEncoding.h>

Classes
struct	FHeader

Static Public Member Functions
static CORE_API bool	Encode (const FIoChunkEncodingParams &Params, FMemoryView RawData, FIoBuffer &OutEncodedData)
static CORE_API bool	Encode (const FIoChunkEncodingParams &Params, FMemoryView RawData, FIoBuffer &OutHeader, FIoBuffer &OutEncodedBlocks)
static CORE_API bool	Decode (const FIoChunkDecodingParams &Params, FMemoryView EncodedBlocks, FMutableMemoryView OutRawData, EIoDecodeFlags Flags=EIoDecodeFlags::None)
static CORE_API bool	Decode (FMemoryView EncodedData, FName CompressionFormat, FMemoryView EncryptionKey, FMutableMemoryView OutRawData, uint64 Offset=0)
static CORE_API FIoChunkBlockDecodeResult	DecodeBlock (const FIoChunkBlockDecodingParams Params, FMutableMemoryView EncodedBlock, FMutableMemoryView OutDecodedBlock)
static CORE_API TIoStatusOr< FIoOffsetAndLength >	GetChunkRange (uint64 TotalRawSize, uint32 RawBlockSize, TConstArrayView< uint32 > EncodedBlockSize, uint64 RawOffset, uint64 RawSize)
static CORE_API TIoStatusOr< FIoOffsetAndLength >	GetChunkRange (const FIoChunkDecodingParams &Params, uint64 RawSize)
static CORE_API uint64	GetTotalEncodedSize (TConstArrayView< uint32 > EncodedBlockSize)
static CORE_API FIoBlockHash	HashBlock (FMemoryView Block)

Static Public Attributes
static constexpr uint32	ExpectedMagic = 0x2e696f
static constexpr uint32	DefaultBlockSize = (64 << 10)
static constexpr uint32	MaxBlockCount = (1 << 24)
static constexpr uint64	MaxSize = (uint64(1) << 40)

Detailed Description

Encodes data into a set of encrypted and compressed blocks. The chunk encoding information is enocoded into a 16 byte header followed by N block sizes.

Member Function Documentation

Decode() [1/2]

bool FIoChunkEncoding::Decode ( const FIoChunkDecodingParams &  Params, FMemoryView  EncodedBlocks, FMutableMemoryView  OutRawData, EIoDecodeFlags  Flags = EIoDecodeFlags::None  )

static

Decode() [2/2]

bool FIoChunkEncoding::Decode ( FMemoryView  EncodedData, FName  CompressionFormat, FMemoryView  EncryptionKey, FMutableMemoryView  OutRawData, uint64  Offset = 0  )

static

DecodeBlock()

FIoChunkBlockDecodeResult FIoChunkEncoding::DecodeBlock ( const FIoChunkBlockDecodingParams  Params, FMutableMemoryView  EncodedBlock, FMutableMemoryView  OutDecodedBlock  )

static

Decode a single I/O store chunk block.

Parameters

Params	Controls whether this function: computes and verifys the block signature using the provided block hash decrypts the block using the provided encryption key decompress the source buffer to the destinatino buffer
EncodedBlock	Memory view of the encoded source buffer. Assumes the underlying size is aligned to AES block size.
OutDecodedBlock	Memory view of the destination buffer.

Note

This function does not copy the bytes from the encoded block unless it is compressed.

Encode() [1/2]

bool FIoChunkEncoding::Encode ( const FIoChunkEncodingParams &  Params, FMemoryView  RawData, FIoBuffer &  OutEncodedData  )

static

Encode() [2/2]

bool FIoChunkEncoding::Encode ( const FIoChunkEncodingParams &  Params, FMemoryView  RawData, FIoBuffer &  OutHeader, FIoBuffer &  OutEncodedBlocks  )

static

GetChunkRange() [1/2]

TIoStatusOr< FIoOffsetAndLength > FIoChunkEncoding::GetChunkRange ( const FIoChunkDecodingParams &  Params, uint64  RawSize  )

static

GetChunkRange() [2/2]

TIoStatusOr< FIoOffsetAndLength > FIoChunkEncoding::GetChunkRange ( uint64  TotalRawSize, uint32  RawBlockSize, TConstArrayView< uint32 >  EncodedBlockSize, uint64  RawOffset, uint64  RawSize  )

static

GetTotalEncodedSize()

uint64 FIoChunkEncoding::GetTotalEncodedSize ( TConstArrayView< uint32 >  EncodedBlockSize )

static

HashBlock()

FIoBlockHash FIoChunkEncoding::HashBlock ( FMemoryView  Block )

static

Member Data Documentation

DefaultBlockSize

constexpr uint32 FIoChunkEncoding::DefaultBlockSize = (64 << 10)

staticconstexpr

ExpectedMagic

constexpr uint32 FIoChunkEncoding::ExpectedMagic = 0x2e696f

staticconstexpr

MaxBlockCount

constexpr uint32 FIoChunkEncoding::MaxBlockCount = (1 << 24)

staticconstexpr

MaxSize

constexpr uint64 FIoChunkEncoding::MaxSize = (uint64(1) << 40)

staticconstexpr

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

• Engine/Source/Runtime/Core/Public/IO/IoChunkEncoding.h
• Engine/Source/Runtime/Core/Private/IO/IoChunkEncoding.cpp