GZIP

GZIP compression and decompression as per IETF RFC 1952. More...

Classes
class	sourcemeta::core::GZIPError
class	sourcemeta::core::GZIPStreamBuffer

Functions
auto SOURCEMETA_CORE_GZIP_EXPORT	sourcemeta::core::gzip (const std::uint8_t *input, std::size_t size, int level=1) -> std::string
auto SOURCEMETA_CORE_GZIP_EXPORT	sourcemeta::core::gunzip (const std::uint8_t *input, std::size_t size, std::size_t output_hint=0, std::size_t maximum_size=268435456) -> std::string

Detailed Description

GZIP compression and decompression as per IETF RFC 1952.

This functionality is included as follows:

#include <sourcemeta/core/gzip.h>

---

Class Documentation

sourcemeta::core::GZIPError

class sourcemeta::core::GZIPError

An error that represents a GZIP compression or decompression failure

Inheritance diagram for sourcemeta::core::GZIPError:

Public Member Functions
	GZIPError (const char *message)
	Construct an error with the given message.
	GZIPError (std::string message)=delete
	GZIPError (std::string &&message)=delete
	GZIPError (std::string_view message)=delete

sourcemeta::core::GZIPStreamBuffer

class sourcemeta::core::GZIPStreamBuffer

A stream buffer that performs streaming GZIP decompression (RFC 1952) over an input stream.

Inheritance diagram for sourcemeta::core::GZIPStreamBuffer:

Public Member Functions
	GZIPStreamBuffer (std::istream &compressed_stream)
	Construct a stream buffer over a compressed input stream.
	GZIPStreamBuffer (const GZIPStreamBuffer &)=delete
	GZIPStreamBuffer (GZIPStreamBuffer &&)=delete
Protected Member Functions
auto	underflow () -> int_type override
	Refill the buffer with more decompressed data.

Function Documentation

gunzip()

auto SOURCEMETA_CORE_GZIP_EXPORT sourcemeta::core::gunzip	(	const std::uint8_t *	input,
		std::size_t	size,
		std::size_t	output_hint = 0,
		std::size_t	maximum_size = 268435456 ) -> std::string

Decompress a GZIP compressed byte buffer (RFC 1952). An optional output size hint can be provided to avoid repeated buffer resizing. The output is bounded by a maximum size (256 MiB by default) so that a highly compressed input cannot exhaust memory, and decompressing beyond it throws. Every concatenated member is decoded and any trailing data that does not begin a new member is ignored, matching gzip(1). For example:

#include <sourcemeta/core/gzip.h>
 
const auto decompressed{sourcemeta::core::gunzip(
    reinterpret_cast<const std::uint8_t *>(compressed.data()),
    compressed.size())};

gzip()

auto SOURCEMETA_CORE_GZIP_EXPORT sourcemeta::core::gzip	(	const std::uint8_t *	input,
		std::size_t	size,
		int	level = 1 ) -> std::string

Compress a byte buffer using the GZIP format (RFC 1952). An optional compression level from 0 to 12 trades speed for ratio. For example:

#include <sourcemeta/core/gzip.h>
 
const std::string input{"hello world"};
const auto compressed{sourcemeta::core::gzip(
    reinterpret_cast<const std::uint8_t *>(input.data()), input.size())};