include/cryptopp/zlib.h

0001 // zlib.h - originally written and placed in the public domain by Wei Dai

0002
0003 /// \file zlib.h

0004 /// \brief ZLIB compression and decompression (RFC 1950)

0005
0006 #ifndef CRYPTOPP_ZLIB_H
0007 #define CRYPTOPP_ZLIB_H
0008
0009 #include "cryptlib.h"
0010 #include "adler32.h"
0011 #include "zdeflate.h"
0012 #include "zinflate.h"
0013
0014 NAMESPACE_BEGIN(CryptoPP)
0015
0016 /// ZLIB Compressor (RFC 1950)

0017 class ZlibCompressor : public Deflator
0018 {
0019 public:
0020     ZlibCompressor(BufferedTransformation *attachment=NULLPTR, unsigned int deflateLevel=DEFAULT_DEFLATE_LEVEL, unsigned int log2WindowSize=DEFAULT_LOG2_WINDOW_SIZE, bool detectUncompressible=true)
0021         : Deflator(attachment, deflateLevel, log2WindowSize, detectUncompressible) {}
0022     ZlibCompressor(const NameValuePairs &parameters, BufferedTransformation *attachment=NULLPTR)
0023         : Deflator(parameters, attachment) {}
0024
0025     unsigned int GetCompressionLevel() const;
0026
0027 protected:
0028     void WritePrestreamHeader();
0029     void ProcessUncompressedData(const byte *string, size_t length);
0030     void WritePoststreamTail();
0031
0032     Adler32 m_adler32;
0033 };
0034
0035 /// ZLIB Decompressor (RFC 1950)

0036 class ZlibDecompressor : public Inflator
0037 {
0038 public:
0039     typedef Inflator::Err Err;
0040     class HeaderErr : public Err {public: HeaderErr() : Err(INVALID_DATA_FORMAT, "ZlibDecompressor: header decoding error") {}};
0041     class Adler32Err : public Err {public: Adler32Err() : Err(DATA_INTEGRITY_CHECK_FAILED, "ZlibDecompressor: ADLER32 check error") {}};
0042     class UnsupportedAlgorithm : public Err {public: UnsupportedAlgorithm() : Err(INVALID_DATA_FORMAT, "ZlibDecompressor: unsupported algorithm") {}};
0043     class UnsupportedPresetDictionary : public Err {public: UnsupportedPresetDictionary() : Err(INVALID_DATA_FORMAT, "ZlibDecompressor: unsupported preset dictionary") {}};
0044
0045     /// \brief Construct a ZlibDecompressor

0046     /// \param attachment a \ BufferedTransformation to attach to this object

0047     /// \param repeat decompress multiple compressed streams in series

0048     /// \param autoSignalPropagation 0 to turn off MessageEnd signal

0049     ZlibDecompressor(BufferedTransformation *attachment = NULLPTR, bool repeat = false, int autoSignalPropagation = -1);
0050     unsigned int GetLog2WindowSize() const {return m_log2WindowSize;}
0051
0052 private:
0053     unsigned int MaxPrestreamHeaderSize() const {return 2;}
0054     void ProcessPrestreamHeader();
0055     void ProcessDecompressedData(const byte *string, size_t length);
0056     unsigned int MaxPoststreamTailSize() const {return 4;}
0057     void ProcessPoststreamTail();
0058
0059     unsigned int m_log2WindowSize;
0060     Adler32 m_adler32;
0061 };
0062
0063 NAMESPACE_END
0064
0065 #endif