winamp/Src/external_dependencies/openmpt-trunk/unarchiver/ungzip.h
2024-09-24 14:54:57 +02:00

74 lines
1.7 KiB
C++

/*
* ungzip.h
* --------
* Purpose: Header file for .gz loader
* Notes : (currently none)
* Authors: OpenMPT Devs
* The OpenMPT source code is released under the BSD license. Read LICENSE for more details.
*/
#pragma once
#include "openmpt/all/BuildSettings.hpp"
#include "openmpt/base/Endian.hpp"
#include "archive.h"
OPENMPT_NAMESPACE_BEGIN
#if defined(MPT_WITH_ZLIB) || defined(MPT_WITH_MINIZ)
class CGzipArchive : public ArchiveBase
{
public:
struct GZheader
{
uint8le magic1; // 0x1F
uint8le magic2; // 0x8B
uint8le method; // 0-7 = reserved, 8 = deflate
uint8le flags; // See GZ_F* constants
uint32le mtime; // UNIX time
uint8le xflags; // Available for use by specific compression methods. We ignore this.
uint8le os; // Which OS was used to compress the file? We also ignore this.
};
struct GZtrailer
{
uint32le crc32_; // CRC32 of decompressed data
uint32le isize; // Size of decompressed data modulo 2^32
};
protected:
enum MagicBytes
{
GZ_HMAGIC1 = 0x1F,
GZ_HMAGIC2 = 0x8B,
GZ_HMDEFLATE = 0x08,
};
enum HeaderFlags
{
GZ_FTEXT = 0x01, // File is probably ASCII text (who cares)
GZ_FHCRC = 0x02, // CRC16 present
GZ_FEXTRA = 0x04, // Extra fields present
GZ_FNAME = 0x08, // Original filename present
GZ_FCOMMENT = 0x10, // Comment is present
GZ_FRESERVED = (~(GZ_FTEXT | GZ_FHCRC | GZ_FEXTRA | GZ_FNAME | GZ_FCOMMENT))
};
GZheader header;
public:
bool ExtractFile(std::size_t index) override;
CGzipArchive(const FileReader &file);
~CGzipArchive() override;
};
MPT_BINARY_STRUCT(CGzipArchive::GZheader, 10)
MPT_BINARY_STRUCT(CGzipArchive::GZtrailer, 8)
#endif // MPT_WITH_ZLIB || MPT_WITH_MINIZ
OPENMPT_NAMESPACE_END