Class providing gzip compression. More...

#include <mdsGZipCompressor.h>

Inheritance diagram for mds::mod::CGZipCompressor:

[legend]

Public Types
enum	{ CLASS_OBJECT }
	Templates that require members of the CObject class can use this enum to check the existence. More...
enum	{ HEAP_OBJECT = 0x70616568 }
	Signature used to recognize objects on the heap. More...
typedef mds::base::CLibraryLockableObject < CChannel >::CLock	tLock
	Lock that have to be used to provide mutual access to write(), read() and etc.
Public Member Functions
	CGZipCompressor (CChannel *channel=NULL, unsigned int level=DEFAULT_COMPRESSION_LEVEL)
	Default constructor.
bool	checkMedium (int Medium) const
	Checks if channel medium is equal to a given value.
bool	checkType (int Type) const
	Checks if channel type corresponds to a given value.
virtual bool	connect (unsigned uTimeout=CH_CONNECTION_TIMEOUT)
	Connects to the opposite channel side.
virtual void	disconnect ()
	Disconnects from the opossite channel side.
virtual bool	flush ()
	Finalizes all writing operations (flushes internal buffers, etc.).
CChannel *	getChannel ()
	Returns pointer to the input/output channel.
int	getCompressionMethod () const
	Returns the compression method.
int	getMedium () const
	Returns the channel medium.
int	getReferencesCount () const
	Returns the number of references.
int	getType () const
	Method returns the channel type.
virtual bool	isConnected ()
	Method for testing channel errors such as:
bool	isOnHeap () const
	Returns true if the object is allocated on the heap.
virtual bool	listen (unsigned uTimeout=CH_CONNECTION_TIMEOUT)
	Listens for the opposite channel side.
void	lock ()
	Locks the object.
	MDS_SHAREDPTR (CGZipCompressor)
	Smart pointer type.
	MDS_SHAREDPTR (CChannelCompressor)
	Smart pointer type.
	MDS_SHAREDPTR (CChannel)
	Smart pointer type.
virtual int	read (char *data, int length)
	Reads and decompresses data from the input channel.
virtual void	setChannel (CChannel *pChannel)
	Sets the input/output channel.
virtual bool	skip (int iLength)
	Skips a given number of bytes.
void	unlock ()
	Locks the object.
virtual bool	wait (unsigned uTimeout=CH_WAIT_TIMEOUT)
	Waits for data.
virtual bool	write (const char *data, int length)
	Writes compressed data to the output channel.
virtual	~CGZipCompressor ()
	Virtual destructor.
Static Public Member Functions
static CChannelCompressor *	create (int CompressionMethod, CChannel *pChannel)
	Channel compressor creation function.
static CChannel *	create (EChannelType eType, const std::string &sDesc)
	Creation of a channel which is described by a textual string.
static void *	operator new (std::size_t Size)
	Allocates a new object on the heap.
static void	separate (const std::string &sDescs, std::vector< std::string > &Descs)
	Parses a given string and separates descriptions of several channels.
Static Public Attributes
static const unsigned int	DEFAULT_COMPRESSION_LEVEL = 6
	Default compression level.
Protected Types
enum	{ BUFFER_SIZE = 4 * 1024 }
	Internal buffer size. More...
typedef mds::base::CStaticData < char, BUFFER_SIZE >	tData
	Storage used by internal buffers.
Protected Member Functions
void	addReference () const
	Increase the reference counter.
bool	delReference () const
	Decrease the reference counter.
Protected Attributes
int	m_ChannelCompression
	Compression method.
tData	m_compressionBuffer
	Internal buffers.
z_stream	m_compressionStream
	ZLib streams.
tSize	m_decompressedTotal
tSize	m_decompressedUsed
tData	m_decompressionBuffer
z_stream	m_decompressionStream
int	m_iHeapObject
	Flag initialized if the object is on the heap.
int	m_iReferences
	The number of references to the object.
int	m_Medium
	Channel medium.
tData	m_readBuffer
CChannelPtr	m_spChannel
	Output/input channel.
int	m_Type
	Channel type.

Detailed Description

Class providing gzip compression.

Member Typedef Documentation

typedef mds::base::CStaticData<char, BUFFER_SIZE> mds::mod::CGZipCompressor::tData [protected]

Storage used by internal buffers.

typedef mds::base::CLibraryLockableObject<CChannel>::CLock mds::mod::CChannel::tLock [inherited]

Lock that have to be used to provide mutual access to write(), read() and etc.

functions.

Member Enumeration Documentation

anonymous enum [protected]

Internal buffer size.

Enumerator:

BUFFER_SIZE

anonymous enum [inherited]

Templates that require members of the CObject class can use this enum to check the existence.

Enumerator:

CLASS_OBJECT

anonymous enum [inherited]

Signature used to recognize objects on the heap.

Enumerator:

HEAP_OBJECT

Constructor & Destructor Documentation

mds::mod::CGZipCompressor::CGZipCompressor	(	CChannel *	channel = `NULL`,
		unsigned int	level = `DEFAULT_COMPRESSION_LEVEL`
	)

Default constructor.

mds::mod::CGZipCompressor::~CGZipCompressor ( ) [virtual]

Virtual destructor.

Member Function Documentation

void mds::base::CObject::addReference ( ) const [protected, inherited]

Increase the reference counter.

bool mds::mod::CChannel::checkMedium ( int Medium ) const [inherited]

Checks if channel medium is equal to a given value.

bool mds::mod::CChannel::checkType ( int Type ) const [inherited]

Checks if channel type corresponds to a given value.

virtual bool mds::mod::CChannelCompressor::connect ( unsigned uTimeout = CH_CONNECTION_TIMEOUT ) [virtual, inherited]

Connects to the opposite channel side.

Returns false on failure and/or timeout elapsed.

Implements mds::mod::CChannel.

CChannelCompressor * mds::mod::CChannelCompressor::create	(	int	CompressionMethod,
		CChannel *	pChannel
	)		`[static, inherited]`

Channel compressor creation function.

Hides call to the CCompressorFactory.
Throws exception on failure!

CChannel * mds::mod::CChannel::create	(	EChannelType	eType,
		const std::string &	sDesc
	)		`[static, inherited]`

Creation of a channel which is described by a textual string.

String has the form: "chmedium[:chattrib1[:chattrib2[:...]]]".
Actually, the channel medium can be "stdio", "file", "pipe" and "shm".
Channel attributes depend on the medium.
"stdio" has empty attributes, "file" (:filename), "pipe" (:pipename) and "shm" (:shmname).
Throws CCannotCreate exception on failure!

bool mds::base::CObject::delReference ( ) const [protected, inherited]

Decrease the reference counter.

Returns true if the decremented number of references is lower or equal to zero and object must be deleted.

virtual void mds::mod::CChannelCompressor::disconnect ( ) [virtual, inherited]

Disconnects from the opossite channel side.

Implements mds::mod::CChannel.

bool mds::mod::CGZipCompressor::flush ( ) [virtual]

Finalizes all writing operations (flushes internal buffers, etc.).

Reimplemented from mds::mod::CChannelCompressor.

CChannel* mds::mod::CChannelCompressor::getChannel ( ) [inherited]

Returns pointer to the input/output channel.

int mds::mod::CChannelCompressor::getCompressionMethod ( ) const [inherited]

Returns the compression method.

int mds::mod::CChannel::getMedium ( ) const [inherited]

Returns the channel medium.

int mds::base::CObject::getReferencesCount ( ) const [inherited]

Returns the number of references.

int mds::mod::CChannel::getType ( ) const [inherited]

Method returns the channel type.

virtual bool mds::mod::CChannelCompressor::isConnected ( ) [virtual, inherited]

Method for testing channel errors such as:

Disconnected or broken channel.
Reading after end of input.

Implements mds::mod::CChannel.

bool mds::base::CObject::isOnHeap ( ) const [inherited]

Returns true if the object is allocated on the heap.

virtual bool mds::mod::CChannelCompressor::listen ( unsigned uTimeout = CH_CONNECTION_TIMEOUT ) [virtual, inherited]

Listens for the opposite channel side.

Returns false on failure and/or timeout elapsed.

Implements mds::mod::CChannel.

void mds::base::CLockableObject< CChannel >::lock ( ) [inherited]

Locks the object.

mds::mod::CGZipCompressor::MDS_SHAREDPTR ( CGZipCompressor )

Smart pointer type.

mds::mod::CChannelCompressor::MDS_SHAREDPTR ( CChannelCompressor ) [inherited]

Smart pointer type.

mds::mod::CChannel::MDS_SHAREDPTR ( CChannel ) [inherited]

Smart pointer type.

static void* mds::base::CObject::operator new ( std::size_t Size ) [static, inherited]

Allocates a new object on the heap.

int mds::mod::CGZipCompressor::read	(	char *	data,
		int	length
	)		`[virtual]`

Reads and decompresses data from the input channel.

In case of error or reading after end of input the number of successfully readed bytes is returned.

Implements mds::mod::CChannelCompressor.

void mds::mod::CChannel::separate	(	const std::string &	sDescs,
		std::vector< std::string > &	Descs
	)		`[static, inherited]`

Parses a given string and separates descriptions of several channels.

Channels are separated by two successive colons "::" in the string.
Example: "chmedium1[:chattribs1][::chmedium2[:chattribs2][::...]]".

virtual void mds::mod::CChannelCompressor::setChannel ( CChannel * pChannel ) [virtual, inherited]

Sets the input/output channel.

Reimplemented in mds::mod::CDensityCompressor.

bool mds::mod::CChannel::skip ( int iLength ) [virtual, inherited]

Skips a given number of bytes.

If the channel is open for readinpg, the data are discarded. Otherwise, zeros are written to the output channel.
This method cannot be used if the channel is opened for reading and writting simultaneously!

Reimplemented in mds::mod::CSharedMemChannel, and mds::mod::CMemoryChannel.

void mds::base::CLockableObject< CChannel >::unlock ( ) [inherited]

Locks the object.

virtual bool mds::mod::CChannelCompressor::wait ( unsigned uTimeout = CH_WAIT_TIMEOUT ) [virtual, inherited]