rpnx::compression::deflate_codec Namespace Reference

Internal implementation shared by raw DEFLATE, zlib, gzip, and ZIP. More...

Classes
class	huffman_decoder
	Canonical Huffman decoder for the bit-reversed codes used by DEFLATE. More...
class	iterator_bit_reader
	LSB-first bit reader that consumes a single-pass byte reader. More...
class	iterator_bit_writer
	LSB-first bit writer that emits bytes through an STL output iterator. More...

Functions
std::uint16_t	reverse_bits (std::uint16_t value, std::uint8_t bit_count) noexcept
	Reverses the selected low bits for DEFLATE wire order.
template<typename writer_type>
void	write_fixed_symbol (writer_type &writer, std::uint16_t symbol)
	Emits one fixed-Huffman literal or length symbol.
std::uint32_t	crc32 (std::span< std::byte const > input) noexcept
	Computes the reflected IEEE CRC-32 used by gzip and ZIP.
template<typename writer_type>
void	compress_fixed_block (writer_type &writer, std::span< std::byte const > input, bool final_block, std::int32_t level)
	Emits one fixed-Huffman DEFLATE block from a bounded search buffer.
template<std::input_iterator input_iterator, std::sentinel_for< input_iterator > sentinel, typename output_iterator>
output_iterator	compress (format stream_format, input_iterator first, sentinel last, output_iterator output, compression_options const &options)
	Compresses an iterator range as raw DEFLATE, zlib, or gzip.
template<std::input_iterator input_iterator, std::sentinel_for< input_iterator > sentinel, typename output_iterator>
output_iterator	decompress (format stream_format, input_iterator first, sentinel last, output_iterator output, decompression_options const &options)
	Decompresses raw DEFLATE, zlib, or gzip input.

Detailed Description

Internal implementation shared by raw DEFLATE, zlib, gzip, and ZIP.

Function Documentation

compress()

template<std::input_iterator input_iterator, std::sentinel_for< input_iterator > sentinel, typename output_iterator>

output_iterator rpnx::compression::deflate_codec::compress	(	format	stream_format,
		input_iterator	first,
		sentinel	last,
		output_iterator	output,
		compression_options const &	options )

Compresses an iterator range as raw DEFLATE, zlib, or gzip.

Template Parameters

input_iterator	Single-pass byte iterator.
sentinel	Sentinel for first.
output_iterator	Destination byte iterator.

Parameters

stream_format	One of format::deflate, format::zlib, or format::gzip.
first	First source byte.
last	Sentinel past the source.
output	Destination iterator.
options	Compression level from 0 through 9.

Returns

Destination advanced past the stream trailer.

Definition at line 408 of file deflate.hpp.

References compress_fixed_block(), rpnx::compression::deflate, rpnx::compression::deflate_codec::iterator_bit_writer< output_iterator >::finish(), rpnx::compression::gzip, rpnx::compression::invalid_option, rpnx::compression::compression_options::level, rpnx::compression::implementation::to_byte(), rpnx::compression::implementation::adler32_accumulator::update(), rpnx::compression::implementation::crc32_accumulator::update(), rpnx::compression::implementation::adler32_accumulator::value(), rpnx::compression::implementation::crc32_accumulator::value(), rpnx::compression::deflate_codec::iterator_bit_writer< output_iterator >::write_bits(), rpnx::compression::implementation::write_byte(), and rpnx::compression::zlib.

compress_fixed_block()

template<typename writer_type>

void rpnx::compression::deflate_codec::compress_fixed_block	(	writer_type &	writer,
		std::span< std::byte const >	input,
		bool	final_block,
		std::int32_t	level )

Emits one fixed-Huffman DEFLATE block from a bounded search buffer.

Template Parameters

writer_type

LSB-first writer providing write_bits().

Parameters

writer	Destination bit writer.
input	Uncompressed block.
final_block	Whether to set the DEFLATE final-block bit.
level	Compression level controlling match-search depth.

Definition at line 317 of file deflate.hpp.

References reverse_bits(), and write_fixed_symbol().

Referenced by compress().

crc32()

std::uint32_t rpnx::compression::deflate_codec::crc32 ( std::span< std::byte const > input )

inlinenodiscardnoexcept

Computes the reflected IEEE CRC-32 used by gzip and ZIP.

Parameters

input

Bytes to checksum.

Returns

Finalized CRC-32.

Definition at line 183 of file deflate.hpp.

Referenced by rpnx::compression::create_zip(), and rpnx::compression::zip_detail::extract_archive().

decompress()

template<std::input_iterator input_iterator, std::sentinel_for< input_iterator > sentinel, typename output_iterator>

output_iterator rpnx::compression::deflate_codec::decompress	(	format	stream_format,
		input_iterator	first,
		sentinel	last,
		output_iterator	output,
		decompression_options const &	options )

Decompresses raw DEFLATE, zlib, or gzip input.

Template Parameters

input_iterator	Single-pass byte iterator.
sentinel	Sentinel for first.
output_iterator	Destination byte iterator.

Parameters

stream_format	One of format::deflate, format::zlib, or format::gzip.
first	First compressed byte.
last	Sentinel past the compressed input.
output	Destination iterator.
options	Output limit and concatenated-member policy.

Returns

Destination advanced past the uncompressed data.

Definition at line 514 of file deflate.hpp.

References rpnx::compression::decompression_options::allow_concatenated_streams, rpnx::compression::deflate_codec::huffman_decoder::build(), rpnx::compression::deflate_codec::huffman_decoder::decode(), rpnx::compression::deflate, rpnx::compression::implementation::byte_reader< input_iterator, sentinel >::empty(), rpnx::compression::gzip, rpnx::compression::invalid_data, rpnx::compression::invalid_option, rpnx::compression::decompression_options::maximum_output_size, rpnx::compression::output_limit_exceeded, rpnx::compression::implementation::byte_reader< input_iterator, sentinel >::read(), rpnx::compression::trailing_data, rpnx::compression::implementation::adler32_accumulator::update(), rpnx::compression::implementation::crc32_accumulator::update(), rpnx::compression::implementation::adler32_accumulator::value(), rpnx::compression::implementation::crc32_accumulator::value(), rpnx::compression::implementation::write_byte(), and rpnx::compression::zlib.

reverse_bits()

std::uint16_t rpnx::compression::deflate_codec::reverse_bits ( std::uint16_t value, std::uint8_t bit_count )

inlinenodiscardnoexcept

Reverses the selected low bits for DEFLATE wire order.

Parameters

value	Value containing the bits to reverse.
bit_count	Number of low bits to reverse.

Returns

Reversed bits in the low part of the result.

Definition at line 140 of file deflate.hpp.

Referenced by compress_fixed_block(), and write_fixed_symbol().

write_fixed_symbol()

template<typename writer_type>

void rpnx::compression::deflate_codec::write_fixed_symbol	(	writer_type &	writer,
		std::uint16_t	symbol )

Emits one fixed-Huffman literal or length symbol.

Template Parameters

writer_type

LSB-first writer providing write_bits().

Parameters

writer	Destination bit writer.
symbol	DEFLATE literal, end-of-block, or length symbol.

Definition at line 158 of file deflate.hpp.

References reverse_bits().

Referenced by compress_fixed_block().