rpnx::compression::xz_codec::range_decoder Class Reference

One-shot LZMA range decoder. More...

#include <xz.hpp>

Public Member Functions
	range_decoder (std::span< std::byte const > input)
	Initializes a decoder from one complete LZMA chunk.
std::uint8_t	decode_bit (std::uint16_t &probability)
	Decodes one adaptive binary symbol.
std::uint32_t	decode_tree (std::span< std::uint16_t > probabilities, std::uint32_t leaf_base)
	Decodes a most-significant-bit-first probability tree.
std::uint32_t	decode_reverse_tree (std::span< std::uint16_t > probabilities, std::ptrdiff_t base, std::uint8_t bit_count)
	Decodes a least-significant-bit-first probability tree.
std::uint32_t	decode_direct (std::uint8_t bit_count)
	Decodes equiprobable direct bits.
void	finish ()
	Validate exact consumption and the LZMA terminal range state.

Detailed Description

One-shot LZMA range decoder.

Definition at line 167 of file xz.hpp.

Constructor & Destructor Documentation

range_decoder()

rpnx::compression::xz_codec::range_decoder::range_decoder ( std::span< std::byte const > input )

inlineexplicit

Initializes a decoder from one complete LZMA chunk.

Parameters

input

Complete range-coded chunk retained for this object's lifetime.

Definition at line 174 of file xz.hpp.

Member Function Documentation

decode_bit()

std::uint8_t rpnx::compression::xz_codec::range_decoder::decode_bit ( std::uint16_t & probability )

inlinenodiscard

Decodes one adaptive binary symbol.

Parameters

probability

Probability updated in place after the decision.

Returns

Zero or one.

Definition at line 191 of file xz.hpp.

References rpnx::compression::xz_codec::probability_move_bits, and rpnx::compression::xz_codec::probability_total.

Referenced by rpnx::compression::xz_codec::decode_length(), rpnx::compression::xz_codec::decode_lzma_chunk(), decode_reverse_tree(), and decode_tree().

decode_direct()

std::uint32_t rpnx::compression::xz_codec::range_decoder::decode_direct ( std::uint8_t bit_count )

inlinenodiscard

Decodes equiprobable direct bits.

Parameters

bit_count

Number of bits to decode.

Returns

Decoded most-significant-bit-first value.

Definition at line 257 of file xz.hpp.

Referenced by rpnx::compression::xz_codec::decode_lzma_chunk().

decode_reverse_tree()

std::uint32_t rpnx::compression::xz_codec::range_decoder::decode_reverse_tree ( std::span< std::uint16_t > probabilities, std::ptrdiff_t base, std::uint8_t bit_count )

inlinenodiscard

Decodes a least-significant-bit-first probability tree.

Parameters

probabilities	Backing probability table updated in place.
base	Offset immediately before the tree's root.
bit_count	Tree depth.

Returns

Reversed decoded value.

Definition at line 234 of file xz.hpp.

References decode_bit(), rpnx::compression::invalid_data, and rpnx::compression::xz.

Referenced by rpnx::compression::xz_codec::decode_lzma_chunk().

decode_tree()

std::uint32_t rpnx::compression::xz_codec::range_decoder::decode_tree ( std::span< std::uint16_t > probabilities, std::uint32_t leaf_base )

inlinenodiscard

Decodes a most-significant-bit-first probability tree.

Parameters

probabilities	Tree probabilities updated in place.
leaf_base	First leaf index, which must be a power of two.

Returns

Tree leaf index including leaf_base.

Definition at line 213 of file xz.hpp.

References decode_bit(), rpnx::compression::invalid_data, and rpnx::compression::xz.

Referenced by rpnx::compression::xz_codec::decode_length(), and rpnx::compression::xz_codec::decode_lzma_chunk().

finish()

void rpnx::compression::xz_codec::range_decoder::finish ( )

inline

Validate exact consumption and the LZMA terminal range state.

Definition at line 276 of file xz.hpp.

References rpnx::compression::invalid_data, and rpnx::compression::xz.

Referenced by rpnx::compression::xz_codec::decode_lzma_chunk().

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

• include/rpnx/compression/implementation/xz.hpp