Abstract class for all connection types. More...

#include <connection.h>

Inheritance diagram for Connection:

Classes
class	ConnectionClosed
	This exception is thrown when trying to read or send a message while the connection is closed. More...

class	ConnectionError
	This exception is thrown in case of a connection related problem. More...

Public Member Functions
	Connection (const Config &config, time_t timeout)
	Constructor. More...

virtual	~Connection ()
	Destructor. More...

virtual void	close ()=0
	Closes an established TCP connection. More...

std::string	tryReceiveMessage ()
	Tries to receive a message from a client. More...

size_t	trySendMessage (const std::string &message)
	Tries to send a message to the client. More...

Private Member Functions
virtual std::string	doReceiveMessage (Config::LengthFieldMessageLength messageLength)=0
	Receives a message. More...

virtual size_t	doSendMessage (const std::string &message)=0
	Sends the selected message. More...

std::string	tryReceiveMessageViaBuffer ()
	Tries to receive a message via fixed-length buffer. More...

std::string	tryReceiveMessageViaLengthField ()
	Tries to receive a message via length field. More...

std::string	receiveFixedLengthMessage (Config::LengthFieldMessageLength messageLength)
	Receives a message of the selected length. More...

size_t	trySendMessageViaLengthField (const std::string &message)
	Tries to send a message via length field. More...

void	sendMessageAtOnce (const std::string &message)
	Sends the selected message at once. More...

	Connection (const Connection &)

Connection &	operator= (const Connection &)

Private Attributes
const Config	_config
	Configuration. More...

time_t	_timeout
	Connection timeout. More...

Detailed Description

Abstract class for all connection types.

Each connection class should derive from this class.

It provides reference semantics (objects copying and comparison is NOT allowed).

Constructor & Destructor Documentation

Connection::Connection	(	const Config &	config,
		time_t	timeout
	)

Constructor.

Parameters

config	Connection configuration.
timeout	Connection timeout (in seconds, if 0 then the timeout is disabled).

virtual Connection::~Connection ( )

virtual

Destructor.

Connection::Connection ( const Connection & )

private

Member Function Documentation

virtual void Connection::close ( )

pure virtual

Closes an established TCP connection.

If the connection is not established, nothing will happen.

Implemented in TCPIPConnection, and SerialConnection.

virtual std::string Connection::doReceiveMessage ( Config::LengthFieldMessageLength messageLength )

privatepure virtual

Receives a message.

Parameters

messageLength Length of the message.

Returns: Received message.

This operation should be nonblocking.

If there is some error, ConnectionError will be thrown. If the connection is closed, ConnectionClosed will be thrown.

Implemented in TCPIPConnection, and SerialConnection.

virtual size_t Connection::doSendMessage ( const std::string & message )

privatepure virtual

Sends the selected message.

Parameters

message Message to be sent.

Returns: Number of sent bytes.

This operation should be nonblocking.

If there is some error, ConnectionError will be thrown. If the connection is closed, ConnectionClosed will be thrown.

Implemented in TCPIPConnection, and SerialConnection.

Connection& Connection::operator= ( const Connection & )

private

std::string Connection::receiveFixedLengthMessage ( Config::LengthFieldMessageLength messageLength )

private

Receives a message of the selected length.

Parameters

messageLength Requested message length.

Returns: Received message.

If there is some error, ConnectionError will be thrown. If the connection is closed, ConnectionClosed will be thrown.

void Connection::sendMessageAtOnce ( const std::string & message )

private

Sends the selected message at once.

Parameters

message Message to be sent.

This method checks timeout and if it expires, it throws ConnectionClosed.

If there is some error, ConnectionError will be thrown. If the connection is closed, ConnectionClosed will be thrown.

std::string Connection::tryReceiveMessage ( )

Tries to receive a message from a client.

Returns: Received message or an empty string if there was no message to be received.

If there is some error, ConnectionError will be thrown. If the connection is closed, ConnectionClosed will be thrown.

std::string Connection::tryReceiveMessageViaBuffer ( )

private

Tries to receive a message via fixed-length buffer.

Returns: Received message or an empty string if there was no message to be received.

If there is some error, ConnectionError will be thrown. If the connection is closed, ConnectionClosed will be thrown.

std::string Connection::tryReceiveMessageViaLengthField ( )

private

Tries to receive a message via length field.

Returns: Received message or an empty string if there was no message to be received.

If there is some error, ConnectionError will be thrown. If the connection is closed, ConnectionClosed will be thrown.

size_t Connection::trySendMessage ( const std::string & message )

Tries to send a message to the client.

Parameters

message Message to be sent.

Returns: Number of bytes that were actually sent (if < message.size(), then the message did not fit into the sending buffer, so try again later - you have to send only the part that wan't sent yet!).

If there is some error, ConnectionError will be thrown. If the connection is closed, ConnectionClosed will be thrown.

size_t Connection::trySendMessageViaLengthField ( const std::string & message )

private

Tries to send a message via length field.

Parameters

message Message to be sent.

Returns: Number of sent bytes.

If the whole message length does not fit into the length field, only the part of the message that can be send will be sent.

This method checks timeout and if it expires, it throws ConnectionClosed.

If there is some error, ConnectionError will be thrown. If the connection is closed, ConnectionClosed will be thrown.

Member Data Documentation

const Config Connection::_config

private

Configuration.

time_t Connection::_timeout

private

Connection timeout.

The documentation for this class was generated from the following file:

/home/s3rvac/tmp/my_projects/src/connection.h

Classes

Public Member Functions

Private Member Functions

Private Attributes

Detailed Description

Constructor & Destructor Documentation

Member Function Documentation

Member Data Documentation