Simone
d074cc7c07
Plugin: ns7zip v2.0.0 Architectures: x86-ansi, x86-unicode, amd64-unicode License: LGPL-2.1-or-later
79 lines
1.9 KiB
C++
79 lines
1.9 KiB
C++
// ZlibDecoder.h
|
|
|
|
#ifndef ZIP7_INC_ZLIB_DECODER_H
|
|
#define ZIP7_INC_ZLIB_DECODER_H
|
|
|
|
#include "DeflateDecoder.h"
|
|
|
|
namespace NCompress {
|
|
namespace NZlib {
|
|
|
|
const UInt32 ADLER_INIT_VAL = 1;
|
|
|
|
Z7_CLASS_IMP_NOQIB_1(
|
|
COutStreamWithAdler
|
|
, ISequentialOutStream
|
|
)
|
|
UInt32 _adler;
|
|
CMyComPtr<ISequentialOutStream> _stream;
|
|
UInt64 _size;
|
|
public:
|
|
void SetStream(ISequentialOutStream *stream) { _stream = stream; }
|
|
void ReleaseStream() { _stream.Release(); }
|
|
void Init() { _adler = ADLER_INIT_VAL; _size = 0; }
|
|
UInt32 GetAdler() const { return _adler; }
|
|
UInt64 GetSize() const { return _size; }
|
|
};
|
|
|
|
Z7_CLASS_IMP_NOQIB_1(
|
|
CDecoder
|
|
, ICompressCoder
|
|
)
|
|
CMyComPtr2<ISequentialOutStream, COutStreamWithAdler> AdlerStream;
|
|
CMyComPtr2<ICompressCoder, NDeflate::NDecoder::CCOMCoder> DeflateDecoder;
|
|
Int32 _inputProcessedSize_Additional;
|
|
public:
|
|
bool IsAdlerOptional;
|
|
|
|
CDecoder(): IsAdlerOptional(false) {}
|
|
UInt64 GetInputProcessedSize() const
|
|
{
|
|
return (UInt64)(
|
|
(Int64)DeflateDecoder->GetInputProcessedSize() +
|
|
(Int64)_inputProcessedSize_Additional);
|
|
}
|
|
UInt64 GetOutputProcessedSize() const { return AdlerStream->GetSize(); }
|
|
};
|
|
|
|
static bool inline IsZlib(const Byte *p)
|
|
{
|
|
if ((p[0] & 0xF) != 8) // method
|
|
return false;
|
|
if (((unsigned)p[0] >> 4) > 7) // logar_window_size minus 8.
|
|
return false;
|
|
if ((p[1] & 0x20) != 0) // dictPresent
|
|
return false;
|
|
if ((((UInt32)p[0] << 8) + p[1]) % 31 != 0)
|
|
return false;
|
|
return true;
|
|
}
|
|
|
|
// IsZlib_3bytes checks 2 bytes of zlib header and starting byte of Deflate stream
|
|
|
|
static bool inline IsZlib_3bytes(const Byte *p)
|
|
{
|
|
if (!IsZlib(p))
|
|
return false;
|
|
const unsigned val = p[2];
|
|
const unsigned blockType = (val >> 1) & 0x3;
|
|
if (blockType == 3) // unsupported block type for deflate
|
|
return false;
|
|
if (blockType == NCompress::NDeflate::NBlockType::kStored && (val >> 3) != 0)
|
|
return false;
|
|
return true;
|
|
}
|
|
|
|
}}
|
|
|
|
#endif
|