Base abstract class for all classes implementing channels. More...

#include <mdsChannel.h>

Inheritance diagram for mds::mod::CChannel:

[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
	CChannel ()
	Exception thrown from constructor, or the create() method, in case of some error.
	CChannel (int Medium, int Type)
	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)=0
	Connects to the opposite channel side.
virtual void	disconnect ()=0
	Disconnects from the opossite channel side.
virtual bool	flush ()=0
	Finalizes all writing/reading operations (flushes internal buffers, etc.).
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 ()=0
	Method for testing channel errors such as: disconnected or broken channel, reading after end of input, etc.
bool	isOnHeap () const
	Returns true if the object is allocated on the heap.
virtual bool	listen (unsigned uTimeout=CH_CONNECTION_TIMEOUT)=0
	Listens for and accepts an incoming connection.
void	lock ()
	Locks the object.
	MDS_SHAREDPTR (CChannel)
	Smart pointer type.
virtual int	read (char *pcData, int iLength)=0
	Reads bytes from the input 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)=0
	Waits for data.
virtual bool	write (const char *pcData, int iLength)=0
	Writes data to the output channel.
virtual	~CChannel ()
	Virtual destructor.
Static Public Member Functions
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.
Protected Member Functions
void	addReference () const
	Increase the reference counter.
bool	delReference () const
	Decrease the reference counter.
Protected Attributes
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.
int	m_Type
	Channel type.

Detailed Description

Base abstract class for all classes implementing channels.

Member Typedef Documentation

typedef mds::base::CLibraryLockableObject<CChannel>::CLock mds::mod::CChannel::tLock

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

functions.

Member Enumeration Documentation

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::CChannel::CChannel ( )

Exception thrown from constructor, or the create() method, in case of some error.

Default constructor.

It doesn't initialize the channel type and medium!
Use with care!

mds::mod::CChannel::CChannel	(	int	Medium,
		int	Type
	)

Constructor.

Initializes the channel type and medium.

virtual mds::mod::CChannel::~CChannel ( ) [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

Checks if channel medium is equal to a given value.

bool mds::mod::CChannel::checkType ( int Type ) const

Checks if channel type corresponds to a given value.

virtual bool mds::mod::CChannel::connect ( unsigned uTimeout = CH_CONNECTION_TIMEOUT ) [pure virtual]

Connects to the opposite channel side.

If the channel is connection oriented, this function must be called on the client side before any communication!
Returns false on failure or timeout elapsed.

Implemented in mds::mod::CSharedMemChannel, mds::mod::CPipeChannel, mds::mod::CFileChannelU, mds::mod::CFileChannel, mds::mod::CStdChannel, mds::mod::CNullChannel, mds::mod::CChannelCompressor, mds::mod::CPredictorChannel, mds::mod::CMemoryChannel, and mds::mod::CBlockChannel.

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

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::CChannel::disconnect ( ) [pure virtual]

Disconnects from the opossite channel side.

The function can be called on the server or client side.

Implemented in mds::mod::CSharedMemChannel, mds::mod::CPipeChannel, mds::mod::CFileChannelU, mds::mod::CFileChannel, mds::mod::CStdChannel, mds::mod::CNullChannel, mds::mod::CChannelCompressor, mds::mod::CPredictorChannel, mds::mod::CBlockChannel, and mds::mod::CMemoryChannel.

virtual bool mds::mod::CChannel::flush ( ) [pure virtual]

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

Implemented in mds::mod::CSharedMemChannel, mds::mod::CPipeChannel, mds::mod::CFileChannelU, mds::mod::CFileChannel, mds::mod::CStdChannel, mds::mod::CNullChannel, mds::mod::CChannelCompressor, mds::mod::CPredictorChannel, mds::mod::CBlockChannel, mds::mod::CMemoryChannel, and mds::mod::CGZipCompressor.

int mds::mod::CChannel::getMedium ( ) const

Returns the channel medium.

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

Returns the number of references.

int mds::mod::CChannel::getType ( ) const

Method returns the channel type.

virtual bool mds::mod::CChannel::isConnected ( ) [pure virtual]

Method for testing channel errors such as: disconnected or broken channel, reading after end of input, etc.

The function can be called on the server or client side.

Implemented in mds::mod::CSharedMemChannel, mds::mod::CPipeChannel, mds::mod::CFileChannelU, mds::mod::CFileChannel, mds::mod::CStdChannel, mds::mod::CNullChannel, mds::mod::CChannelCompressor, mds::mod::CPredictorChannel, mds::mod::CBlockChannel, and mds::mod::CMemoryChannel.

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

Returns true if the object is allocated on the heap.

virtual bool mds::mod::CChannel::listen ( unsigned uTimeout = CH_CONNECTION_TIMEOUT ) [pure virtual]

Listens for and accepts an incoming connection.

If the channel is connection oriented, this function must be called on the server side before any communication!
Returns false on failure or timeout elapsed.

Implemented in mds::mod::CSharedMemChannel, mds::mod::CPipeChannel, mds::mod::CFileChannelU, mds::mod::CFileChannel, mds::mod::CStdChannel, mds::mod::CNullChannel, mds::mod::CChannelCompressor, mds::mod::CPredictorChannel, mds::mod::CBlockChannel, and mds::mod::CMemoryChannel.

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

Locks the object.

mds::mod::CChannel::MDS_SHAREDPTR ( CChannel )

Smart pointer type.

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

Allocates a new object on the heap.

virtual int mds::mod::CChannel::read	(	char *	pcData,
		int	iLength
	)		`[pure virtual]`

Reads bytes from the input channel.

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

Implemented in mds::mod::CSharedMemChannel, mds::mod::CPipeChannel, mds::mod::CFileChannelU, mds::mod::CFileChannel, mds::mod::CStdChannel, mds::mod::CNullChannel, mds::mod::CDensityPredictor, mds::mod::CRawCompressor, mds::mod::CByteTranspose< T >, mds::mod::CChannelCompressor, mds::mod::CPredictorChannel, mds::mod::CBlockChannel, mds::mod::CRLE16Compressor, mds::mod::CMemoryChannel, mds::mod::CGZipCompressor, mds::mod::CDensityCompressor, and mds::mod::CRLE8Compressor.

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

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][::...]]".

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

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::CChannel::wait ( unsigned uTimeout = CH_WAIT_TIMEOUT ) [pure virtual]