zlib.h

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// zlib.h - originally written and placed in the public domain by Wei Dai
 
/// \file zlib.h
/// \brief ZLIB compression and decompression (RFC 1950)
 
#ifndef CRYPTOPP_ZLIB_H
#define CRYPTOPP_ZLIB_H
 
#include "cryptlib.h"
#include "adler32.h"
#include "zdeflate.h"
#include "zinflate.h"
 
NAMESPACE_BEGIN(CryptoPP)
 
/// ZLIB Compressor (RFC 1950)
class ZlibCompressor : public Deflator
{
public:
    ZlibCompressor(BufferedTransformation *attachment=NULLPTR, unsigned int deflateLevel=DEFAULT_DEFLATE_LEVEL, unsigned int log2WindowSize=DEFAULT_LOG2_WINDOW_SIZE, bool detectUncompressible=true)
        : Deflator(attachment, deflateLevel, log2WindowSize, detectUncompressible) {}
    ZlibCompressor(const NameValuePairs &parameters, BufferedTransformation *attachment=NULLPTR)
        : Deflator(parameters, attachment) {}
 
    unsigned int GetCompressionLevel() const;
 
protected:
    void WritePrestreamHeader();
    void ProcessUncompressedData(const byte *string, size_t length);
    void WritePoststreamTail();
 
    Adler32 m_adler32;
};
 
/// ZLIB Decompressor (RFC 1950)
class ZlibDecompressor : public Inflator
{
public:
    typedef Inflator::Err Err;
    class HeaderErr : public Err {public: HeaderErr() : Err(INVALID_DATA_FORMAT, "ZlibDecompressor: header decoding error") {}};
    class Adler32Err : public Err {public: Adler32Err() : Err(DATA_INTEGRITY_CHECK_FAILED, "ZlibDecompressor: ADLER32 check error") {}};
    class UnsupportedAlgorithm : public Err {public: UnsupportedAlgorithm() : Err(INVALID_DATA_FORMAT, "ZlibDecompressor: unsupported algorithm") {}};
    class UnsupportedPresetDictionary : public Err {public: UnsupportedPresetDictionary() : Err(INVALID_DATA_FORMAT, "ZlibDecompressor: unsupported preset dictionary") {}};
 
    /// \brief Construct a ZlibDecompressor
    /// \param attachment a \ BufferedTransformation to attach to this object
    /// \param repeat decompress multiple compressed streams in series
    /// \param autoSignalPropagation 0 to turn off MessageEnd signal
    ZlibDecompressor(BufferedTransformation *attachment = NULLPTR, bool repeat = false, int autoSignalPropagation = -1);
    unsigned int GetLog2WindowSize() const {return m_log2WindowSize;}
 
private:
    unsigned int MaxPrestreamHeaderSize() const {return 2;}
    void ProcessPrestreamHeader();
    void ProcessDecompressedData(const byte *string, size_t length);
    unsigned int MaxPoststreamTailSize() const {return 4;}
    void ProcessPoststreamTail();
 
    unsigned int m_log2WindowSize;
    Adler32 m_adler32;
};
 
NAMESPACE_END
 
#endif