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ZlibCompressor Class Reference

#include <zlib.h>

Inheritance diagram for ZlibCompressor:

Deflator LowFirstBitWriter Filter BufferedTransformation Algorithm Waitable Clonable List of all members.

Detailed Description

ZLIB Compressor (RFC 1950).

Definition at line 11 of file zlib.h.


virtual bool IsolatedMessageSeriesEnd (bool blocking)
virtual void SetAutoSignalPropagation (int propagation)
 set propagation of automatically generated and transferred signals
virtual int GetAutoSignalPropagation () const

Public Types


Public Member Functions

 ZlibCompressor (BufferedTransformation *attachment=NULL, unsigned int deflateLevel=DEFAULT_DEFLATE_LEVEL, unsigned int log2WindowSize=DEFAULT_LOG2_WINDOW_SIZE, bool detectUncompressible=true)
 ZlibCompressor (const NameValuePairs &parameters, BufferedTransformation *attachment=NULL)
unsigned int GetCompressionLevel () const
void SetDeflateLevel (int deflateLevel)
 this function can be used to set the deflate level in the middle of compression
int GetDeflateLevel () const
int GetLog2WindowSize () const
void IsolatedInitialize (const NameValuePairs &parameters)
unsigned int Put2 (const byte *inString, unsigned int length, int messageEnd, bool blocking)
 input multiple bytes for blocking or non-blocking processing
bool IsolatedFlush (bool hardFlush, bool blocking)
void PutBits (unsigned long value, unsigned int length)
void FlushBitBuffer ()
void ClearBitBuffer ()
void StartCounting ()
unsigned long FinishCounting ()
bool Attachable ()
 returns whether this object allows attachment
BufferedTransformationAttachedTransformation ()
 returns the object immediately attached to this object or NULL for no attachment
const BufferedTransformationAttachedTransformation () const
void Detach (BufferedTransformation *newAttachment=NULL)
 delete the current attachment chain and replace it with newAttachment
unsigned int TransferTo2 (BufferedTransformation &target, unsigned long &transferBytes, const std::string &channel=NULL_CHANNEL, bool blocking=true)
unsigned int CopyRangeTo2 (BufferedTransformation &target, unsigned long &begin, unsigned long end=ULONG_MAX, const std::string &channel=NULL_CHANNEL, bool blocking=true) const
void Initialize (const NameValuePairs &parameters=g_nullNameValuePairs, int propagation=-1)
 initialize or reinitialize this object
bool Flush (bool hardFlush, int propagation=-1, bool blocking=true)
 flush buffered input and/or output
bool MessageSeriesEnd (int propagation=-1, bool blocking=true)
 mark end of a series of messages
BufferedTransformationRef ()
 return a reference to this object
virtual std::string AlgorithmName () const
 returns name of this algorithm, not universally implemented yet
virtual ClonableClone () const
 this is not implemented by most classes yet
bool Wait (unsigned long milliseconds)
 wait on this object

Static Public Attributes

const std::string NULL_CHANNEL

Protected Types

enum  { STORED = 0, STATIC = 1, DYNAMIC = 2 }
enum  { MIN_MATCH = 3, MAX_MATCH = 258 }

Protected Member Functions

void WritePrestreamHeader ()
void ProcessUncompressedData (const byte *string, unsigned int length)
void WritePoststreamTail ()
void InitializeStaticEncoders ()
void Reset (bool forceReset=false)
unsigned int FillWindow (const byte *str, unsigned int length)
unsigned int ComputeHash (const byte *str) const
unsigned int LongestMatch (unsigned int &bestMatch) const
void InsertString (unsigned int start)
void ProcessBuffer ()
void LiteralByte (byte b)
void MatchFound (unsigned int distance, unsigned int length)
void EncodeBlock (bool eof, unsigned int blockType)
void EndBlock (bool eof)
virtual BufferedTransformationNewDefaultAttachment () const
void Insert (Filter *nextFilter)
virtual bool ShouldPropagateMessageEnd () const
virtual bool ShouldPropagateMessageSeriesEnd () const
void PropagateInitialize (const NameValuePairs &parameters, int propagation)
unsigned int Output (int outputSite, const byte *inString, unsigned int length, int messageEnd, bool blocking, const std::string &channel=NULL_CHANNEL)
unsigned int OutputModifiable (int outputSite, byte *inString, unsigned int length, int messageEnd, bool blocking, const std::string &channel=NULL_CHANNEL)
bool OutputMessageEnd (int outputSite, int propagation, bool blocking, const std::string &channel=NULL_CHANNEL)
bool OutputFlush (int outputSite, bool hardFlush, int propagation, bool blocking, const std::string &channel=NULL_CHANNEL)
bool OutputMessageSeriesEnd (int outputSite, int propagation, bool blocking, const std::string &channel=NULL_CHANNEL)

Static Protected Member Functions

int DecrementPropagation (int propagation)

Protected Attributes

Adler32 m_adler32
int m_deflateLevel
int m_log2WindowSize
int m_compressibleDeflateLevel
unsigned int m_detectSkip
unsigned int m_detectCount
unsigned int DSIZE
unsigned int DMASK
unsigned int HSIZE
unsigned int HMASK
unsigned int GOOD_MATCH
unsigned int MAX_LAZYLENGTH
unsigned int MAX_CHAIN_LENGTH
bool m_headerWritten
bool m_matchAvailable
unsigned int m_dictionaryEnd
unsigned int m_stringStart
unsigned int m_lookahead
unsigned int m_minLookahead
unsigned int m_previousMatch
unsigned int m_previousLength
HuffmanEncoder m_staticLiteralEncoder
HuffmanEncoder m_staticDistanceEncoder
HuffmanEncoder m_dynamicLiteralEncoder
HuffmanEncoder m_dynamicDistanceEncoder
SecByteBlock m_byteBuffer
SecBlock< word16 > m_head
SecBlock< word16 > m_prev
FixedSizeSecBlock< unsigned
int, 286 > 
FixedSizeSecBlock< unsigned
int, 30 > 
SecBlock< EncodedMatch > m_matchBuffer
unsigned int m_matchBufferEnd
unsigned int m_blockStart
unsigned int m_blockLength
bool m_counting
unsigned long m_bitCount
unsigned long m_buffer
unsigned int m_bitsBuffered
unsigned int m_bytesBuffered
FixedSizeSecBlock< byte, 256 > m_outputBuffer
unsigned int m_inputPosition
int m_continueAt

Member Function Documentation

unsigned int Deflator::Put2 const byte *  inString,
unsigned int  length,
int  messageEnd,
bool  blocking
[virtual, inherited]

input multiple bytes for blocking or non-blocking processing

messageEnd means how many filters to signal MessageEnd to, including this one

Implements BufferedTransformation.

Definition at line 477 of file zdeflate.cpp.

bool Filter::Attachable  )  [inline, virtual, inherited]

returns whether this object allows attachment

Some BufferedTransformation objects (e.g. Filter objects) allow other BufferedTransformation objects to be attached. When this is done, the first object instead of buffering its output, sents that output to the attached object as input. The entire attachment chain is deleted when the anchor object is destructed.

Reimplemented from BufferedTransformation.

Definition at line 19 of file filters.h.

bool Filter::Flush bool  hardFlush,
int  propagation = -1,
bool  blocking = true
[virtual, inherited]

flush buffered input and/or output

hardFlush is used to indicate whether all data should be flushed
Hard flushes must be used with care. It means try to process and output everything, even if there may not be enough data to complete the action. For example, hard flushing a HexDecoder would cause an error if you do it after inputing an odd number of hex encoded characters. For some types of filters, for example ZlibDecompressor, hard flushes can only be done at "synchronization points". These synchronization points are positions in the data stream that are created by hard flushes on the corresponding reverse filters, in this example ZlibCompressor. This is useful when zlib compressed data is moved across a network in packets and compression state is preserved across packets, as in the ssh2 protocol.

Reimplemented from BufferedTransformation.

Reimplemented in SecretSharing, and InformationDispersal.

Definition at line 68 of file filters.cpp.

bool Filter::MessageSeriesEnd int  propagation = -1,
bool  blocking = true
[virtual, inherited]

mark end of a series of messages

There should be a MessageEnd immediately before MessageSeriesEnd.

Reimplemented from BufferedTransformation.

Definition at line 82 of file filters.cpp.

BufferedTransformation& BufferedTransformation::Ref  )  [inline, inherited]

return a reference to this object

This function is useful for passing a temporary BufferedTransformation object to a function that takes a non-const reference. Definition at line 711 of file cryptlib.h.

virtual byte* BufferedTransformation::CreatePutSpace unsigned int &  size  )  [inline, virtual, inherited]

request space which can be written into by the caller, and then used as input to Put()

The purpose of this method is to help avoid doing extra memory allocations.

Reimplemented in MeterFilter, HashFilter, Redirector, ArraySink, ArrayXorSink, and ByteQueue.

Definition at line 730 of file cryptlib.h.

Referenced by ArrayXorSink::CreatePutSpace().

virtual unsigned int BufferedTransformation::PutModifiable2 byte *  inString,
unsigned int  length,
int  messageEnd,
bool  blocking
[inline, virtual, inherited]

input multiple bytes that may be modified by callee for blocking or non-blocking processing

messageEnd means how many filters to signal MessageEnd to, including this one

Reimplemented in MeterFilter, and FilterWithBufferedInput.

Definition at line 748 of file cryptlib.h.

virtual void BufferedTransformation::SetAutoSignalPropagation int  propagation  )  [inline, virtual, inherited]

set propagation of automatically generated and transferred signals

propagation == 0 means do not automaticly generate signals

Reimplemented in SourceTemplate< T >, SourceTemplate< FileStore >, SourceTemplate< RandomNumberStore >, and SourceTemplate< StringStore >.

Definition at line 788 of file cryptlib.h.

unsigned long BufferedTransformation::MaxRetrievable  )  const [virtual, inherited]

returns number of bytes that is currently ready for retrieval

All retrieval functions return the actual number of bytes retrieved, which is the lesser of the request number and MaxRetrievable().

Reimplemented in FileStore, RandomNumberStore, NullStore, MessageQueue, ByteQueue, and RandomPool.

Definition at line 247 of file cryptlib.cpp.

References BufferedTransformation::AttachedTransformation(), and BufferedTransformation::CopyTo().

Referenced by RandomNumberStore::AnyRetrievable(), and Integer::BERDecode().

bool BufferedTransformation::GetNextMessage  )  [virtual, inherited]

start retrieving the next message

Returns false if no more messages exist or this message is not completely retrieved.

Reimplemented in MessageQueue, and Store.

Definition at line 336 of file cryptlib.cpp.

References BufferedTransformation::AnyMessages(), and BufferedTransformation::AttachedTransformation().

bool Waitable::Wait unsigned long  milliseconds  )  [inherited]

wait on this object

same as creating an empty container, calling GetWaitObjects(), and calling Wait() on the container Definition at line 321 of file wait.cpp.

References Waitable::GetWaitObjects(), and WaitObjectContainer::Wait().

Referenced by NetworkSource::GeneralPump2(), and NetworkSink::TimedFlush().

The documentation for this class was generated from the following files:
Generated on Wed Jul 21 19:16:18 2004 for Crypto++ by doxygen 1.3.7-20040704