#include "BaseUefiDecompressLibInternals.h"

Functions
VOID	FillBuf (IN SCRATCH_DATA *Sd, IN UINT16 NumOfBits)

UINT32	GetBits (IN SCRATCH_DATA *Sd, IN UINT16 NumOfBits)

UINT16	MakeTable (IN SCRATCH_DATA Sd, IN UINT16 NumOfChar, IN UINT8 BitLen, IN UINT16 TableBits, OUT UINT16 *Table)

UINT32	DecodeP (IN SCRATCH_DATA *Sd)

UINT16	ReadPTLen (IN SCRATCH_DATA *Sd, IN UINT16 nn, IN UINT16 nbit, IN UINT16 Special)

VOID	ReadCLen (SCRATCH_DATA *Sd)

UINT16	DecodeC (SCRATCH_DATA *Sd)

VOID	Decode (SCRATCH_DATA *Sd)

RETURN_STATUS EFIAPI	UefiDecompressGetInfo (IN CONST VOID Source, IN UINT32 SourceSize, OUT UINT32 DestinationSize, OUT UINT32 *ScratchSize)

RETURN_STATUS	UefiTianoDecompress (IN CONST VOID Source, IN OUT VOID Destination, IN OUT VOID *Scratch, IN UINT32 Version)

RETURN_STATUS EFIAPI	UefiDecompress (IN CONST VOID Source, IN OUT VOID Destination, IN OUT VOID *Scratch OPTIONAL)

Detailed Description

UEFI Decompress Library implementation refer to UEFI specification.

Copyright (c) 2006 - 2019, Intel Corporation. All rights reserved.
Portions copyright (c) 2008 - 2009, Apple Inc. All rights reserved.
SPDX-License-Identifier: BSD-2-Clause-Patent

Definition in file BaseUefiDecompressLib.c.

Function Documentation

◆ Decode()

VOID Decode ( SCRATCH_DATA * Sd )

Decode the source data and put the resulting data into the destination buffer.

Parameters

Sd	The global scratch data.

Definition at line 555 of file BaseUefiDecompressLib.c.

◆ DecodeC()

UINT16 DecodeC ( SCRATCH_DATA * Sd )

Decode a character/length value.

Read one value from mBitBuf, Get one code from mBitBuf. If it is at block boundary, generates Huffman code mapping table for Extra Set, Code&Len Set and Position Set.

Parameters

Sd	The global scratch data.

Returns: The value decoded.

Definition at line 481 of file BaseUefiDecompressLib.c.

◆ DecodeP()

UINT32 DecodeP ( IN SCRATCH_DATA * Sd )

Decodes a position value.

Get a position value according to Position Huffman Table.

Parameters

Sd	The global scratch data.

Returns: The position value decoded.

Definition at line 262 of file BaseUefiDecompressLib.c.

◆ FillBuf()

VOID FillBuf	(	IN SCRATCH_DATA *	Sd,
		IN UINT16	NumOfBits
	)

Read NumOfBit of bits from source into mBitBuf.

Shift mBitBuf NumOfBits left. Read in NumOfBits of bits from source.

Parameters

Sd	The global scratch data.
NumOfBits	The number of bits to shift and read.

Definition at line 22 of file BaseUefiDecompressLib.c.

◆ GetBits()

UINT32 GetBits	(	IN SCRATCH_DATA *	Sd,
		IN UINT16	NumOfBits
	)

Get NumOfBits of bits out from mBitBuf.

Get NumOfBits of bits out from mBitBuf. Fill mBitBuf with subsequent NumOfBits of bits from source. Returns NumOfBits of bits that are popped out.

Parameters

Sd	The global scratch data.
NumOfBits	The number of bits to pop and read.

Returns: The bits that are popped out.

Definition at line 80 of file BaseUefiDecompressLib.c.

◆ MakeTable()

UINT16 MakeTable	(	IN SCRATCH_DATA *	Sd,
		IN UINT16	NumOfChar,
		IN UINT8 *	BitLen,
		IN UINT16	TableBits,
		OUT UINT16 *	Table
	)

Creates Huffman Code mapping table according to code length array.

Creates Huffman Code mapping table for Extra Set, Char&Len Set and Position Set according to code length array. If TableBits > 16, then ASSERT ().

Parameters

Sd	The global scratch data.
NumOfChar	The number of symbols in the symbol set.
BitLen	Code length array.
TableBits	The width of the mapping table.
Table	The table to be created.

Return values

0	OK.
BAD_TABLE	The table is corrupted.

Definition at line 118 of file BaseUefiDecompressLib.c.

◆ ReadCLen()

VOID ReadCLen ( SCRATCH_DATA * Sd )

Reads code lengths for Char&Len Set.

Read in and decode the Char&Len Set Code Length Array, then generate the Huffman Code mapping table for the Char&Len Set.

Parameters

Sd	The global scratch data.

Definition at line 399 of file BaseUefiDecompressLib.c.

◆ ReadPTLen()

UINT16 ReadPTLen	(	IN SCRATCH_DATA *	Sd,
		IN UINT16	nn,
		IN UINT16	nbit,
		IN UINT16	Special
	)

Reads code lengths for the Extra Set or the Position Set.

Read in the Extra Set or Position Set Length Array, then generate the Huffman code mapping for them.

Parameters

Sd	The global scratch data.
nn	The number of symbols.
nbit	The number of bits needed to represent nn.
Special	The special symbol that needs to be taken care of.

Return values

0	OK.
BAD_TABLE	Table is corrupted.

Definition at line 315 of file BaseUefiDecompressLib.c.

◆ UefiDecompress()

RETURN_STATUS EFIAPI UefiDecompress	(	IN CONST VOID *	Source,
		IN OUT VOID *	Destination,
		IN OUT VOID *Scratch	OPTIONAL
	)

Decompresses a UEFI compressed source buffer.

Extracts decompressed data to its original form. This function is designed so that the decompression algorithm can be implemented without using any memory services. As a result, this function is not allowed to call any memory allocation services in its implementation. It is the caller's responsibility to allocate and free the Destination and Scratch buffers. If the compressed source data specified by Source is successfully decompressed into Destination, then RETURN_SUCCESS is returned. If the compressed source data specified by Source is not in a valid compressed data format, then RETURN_INVALID_PARAMETER is returned.

If Source is NULL, then ASSERT(). If Destination is NULL, then ASSERT(). If the required scratch buffer size > 0 and Scratch is NULL, then ASSERT().

Parameters

Source	The source buffer containing the compressed data.
Destination	The destination buffer to store the decompressed data
Scratch	A temporary scratch buffer that is used to perform the decompression. This is an optional parameter that may be NULL if the required scratch buffer size is 0.

Return values

RETURN_SUCCESS	Decompression completed successfully, and the uncompressed buffer is returned in Destination.
RETURN_INVALID_PARAMETER	The source buffer specified by Source is corrupted (not in a valid compressed format).

Definition at line 849 of file BaseUefiDecompressLib.c.

◆ UefiDecompressGetInfo()

RETURN_STATUS EFIAPI UefiDecompressGetInfo	(	IN CONST VOID *	Source,
		IN UINT32	SourceSize,
		OUT UINT32 *	DestinationSize,
		OUT UINT32 *	ScratchSize
	)

Given a compressed source buffer, this function retrieves the size of the uncompressed buffer and the size of the scratch buffer required to decompress the compressed source buffer.

Retrieves the size of the uncompressed buffer and the temporary scratch buffer required to decompress the buffer specified by Source and SourceSize. If the size of the uncompressed buffer or the size of the scratch buffer cannot be determined from the compressed data specified by Source and SourceData, then RETURN_INVALID_PARAMETER is returned. Otherwise, the size of the uncompressed buffer is returned in DestinationSize, the size of the scratch buffer is returned in ScratchSize, and RETURN_SUCCESS is returned. This function does not have scratch buffer available to perform a thorough checking of the validity of the source data. It just retrieves the "Original Size" field from the beginning bytes of the source data and output it as DestinationSize. And ScratchSize is specific to the decompression implementation.

If Source is NULL, then ASSERT(). If DestinationSize is NULL, then ASSERT(). If ScratchSize is NULL, then ASSERT().

Parameters

Source	The source buffer containing the compressed data.
SourceSize	The size, in bytes, of the source buffer.
DestinationSize	A pointer to the size, in bytes, of the uncompressed buffer that will be generated when the compressed buffer specified by Source and SourceSize is decompressed.
ScratchSize	A pointer to the size, in bytes, of the scratch buffer that is required to decompress the compressed buffer specified by Source and SourceSize.

Return values

RETURN_SUCCESS	The size of the uncompressed data was returned in DestinationSize, and the size of the scratch buffer was returned in ScratchSize.
RETURN_INVALID_PARAMETER	The size of the uncompressed data or the size of the scratch buffer cannot be determined from the compressed data specified by Source and SourceSize.

Definition at line 678 of file BaseUefiDecompressLib.c.

◆ UefiTianoDecompress()

RETURN_STATUS UefiTianoDecompress	(	IN CONST VOID *	Source,
		IN OUT VOID *	Destination,
		IN OUT VOID *	Scratch,
		IN UINT32	Version
	)

Decompresses a compressed source buffer.

Extracts decompressed data to its original form. This function is designed so that the decompression algorithm can be implemented without using any memory services. As a result, this function is not allowed to call any memory allocation services in its implementation. It is the caller's responsibility to allocate and free the Destination and Scratch buffers. If the compressed source data specified by Source is successfully decompressed into Destination, then RETURN_SUCCESS is returned. If the compressed source data specified by Source is not in a valid compressed data format, then RETURN_INVALID_PARAMETER is returned.

If Source is NULL, then ASSERT(). If Destination is NULL, then ASSERT(). If the required scratch buffer size > 0 and Scratch is NULL, then ASSERT(). If the Version is not 1 or 2, then ASSERT().

Parameters

Source	The source buffer containing the compressed data.
Destination	The destination buffer to store the decompressed data.
Scratch	A temporary scratch buffer that is used to perform the decompression. This is an optional parameter that may be NULL if the required scratch buffer size is 0.
Version	1 for UEFI Decompress algoruthm, 2 for Tiano Decompess algorithm.

Return values

RETURN_SUCCESS	Decompression completed successfully, and the uncompressed buffer is returned in Destination.
RETURN_INVALID_PARAMETER	The source buffer specified by Source is corrupted (not in a valid compressed format).

Definition at line 738 of file BaseUefiDecompressLib.c.

Functions

Detailed Description

Function Documentation

◆ Decode()

◆ DecodeC()

◆ DecodeP()

◆ FillBuf()

◆ GetBits()

◆ MakeTable()

◆ ReadCLen()

◆ ReadPTLen()

◆ UefiDecompress()

◆ UefiDecompressGetInfo()

◆ UefiTianoDecompress()