Accepts and handles a single TCP connection. More...

#include <tcp_connection.h>

Inheritance diagram for isc::tcp::TcpConnection:

Public Member Functions
	TcpConnection (const asiolink::IOServicePtr &io_service, const TcpConnectionAcceptorPtr &acceptor, const asiolink::TlsContextPtr &tls_context, TcpConnectionPool &connection_pool, const TcpConnectionAcceptorCallback &acceptor_callback, const TcpConnectionFilterCallback &connection_filter, const long idle_timeout, const size_t read_max=32768)
	Constructor.

virtual	~TcpConnection ()
	Destructor.

void	asyncAccept ()
	Asynchronously accepts new connection.

virtual void	close ()
	Closes the socket.

virtual TcpRequestPtr	createRequest ()=0
	Creates a new, empty request.

void	doHandshake ()
	Asynchronously performs TLS handshake.

void	doRead (TcpRequestPtr request=TcpRequestPtr())
	Starts asynchronous read from the socket.

size_t	getReadMax () const
	Fetches the maximum number of bytes read during single socket read.

const boost::asio::ip::tcp::endpoint	getRemoteEndpoint () const
	Fetches the remote endpoint for the connection's socket.

TcpRequestPtr	postData (TcpRequestPtr request, WireData &input_data)
	Appends newly received raw data to the given request.

virtual void	requestReceived (TcpRequestPtr request)=0
	Processes a request once it has been completely received.

virtual bool	responseSent (TcpResponsePtr response)=0
	Determines behavior after a response has been sent.

void	setReadMax (const size_t read_max)
	Sets the maximum number of bytes read during single socket read.

virtual void	shutdown ()
	Shutdown the socket.

Static Public Member Functions
static const boost::asio::ip::tcp::endpoint &	NO_ENDPOINT ()
	Returns an empty end point.

Protected Member Functions
void	acceptorCallback (const boost::system::error_code &ec)
	Local callback invoked when new connection is accepted.

void	asyncSendResponse (TcpResponsePtr response)
	Sends TCP response asynchronously.

void	doWrite (TcpResponsePtr response)
	Starts asynchronous write to the socket.

unsigned char *	getInputBufData ()
	Returns pointer to the first byte of the input buffer.

size_t	getInputBufSize () const
	Returns input buffer size.

std::string	getRemoteEndpointAddressAsText () const
	returns remote address in textual form

void	handshakeCallback (const boost::system::error_code &ec)
	Local callback invoked when TLS handshake is performed.

void	idleTimeoutCallback ()
	Callback invoked when the client has been idle.

void	setupIdleTimer ()
	Reset timer for detecting idle timeout in connections.

void	shutdownCallback (const boost::system::error_code &ec)
	Callback invoked when TLS shutdown is performed.

virtual void	shutdownConnection ()
	Shuts down current connection.

void	socketReadCallback (TcpRequestPtr request, boost::system::error_code ec, size_t length)
	Callback invoked when new data is received over the socket.

virtual void	socketWriteCallback (TcpResponsePtr request, boost::system::error_code ec, size_t length)
	Callback invoked when data is sent over the socket.

virtual void	stopThisConnection ()
	Stops current connection.

Protected Attributes
TcpConnectionAcceptorPtr	acceptor_
	Pointer to the TCP acceptor used to accept new connections.

TcpConnectionAcceptorCallback	acceptor_callback_
	External TCP acceptor callback.

TcpConnectionFilterCallback	connection_filter_
	External callback for filtering connections by IP address.

TcpConnectionPool &	connection_pool_
	Connection pool holding this connection.

long	idle_timeout_
	Timeout after which the a TCP connection is shut down by the server.

asiolink::IntervalTimer	idle_timer_
	Timer used to detect idle Timeout.

WireData	input_buf_
	Buffer for a single socket read.

asiolink::IOServicePtr	io_service_
	The IO service used to handle events.

size_t	read_max_
	Maximum bytes to read in a single socket read.

boost::asio::ip::tcp::endpoint	remote_endpoint_
	Remote endpoint.

std::unique_ptr< asiolink::TCPSocket< SocketCallback > >	tcp_socket_
	TCP socket used by this connection.

asiolink::TlsContextPtr	tls_context_
	TLS context.

std::unique_ptr< asiolink::TLSSocket< SocketCallback > >	tls_socket_
	TLS socket used by this connection.

Detailed Description

Accepts and handles a single TCP connection.

Definition at line 157 of file tcp_connection.h.

Constructor & Destructor Documentation

◆ TcpConnection()

isc::tcp::TcpConnection::TcpConnection	(	const asiolink::IOServicePtr &	io_service,
		const TcpConnectionAcceptorPtr &	acceptor,
		const asiolink::TlsContextPtr &	tls_context,
		TcpConnectionPool &	connection_pool,
		const TcpConnectionAcceptorCallback &	acceptor_callback,
		const TcpConnectionFilterCallback &	connection_filter,
		const long	idle_timeout,
		const size_t	read_max = `32768`
	)

Constructor.

Parameters

io_service	IO service to be used by the connection.
acceptor	Pointer to the TCP acceptor object used to listen for new TCP connections.
tls_context	TLS context.
connection_pool	Connection pool in which this connection is stored.
acceptor_callback	Callback invoked when new connection is accepted.
connection_filter	Callback invoked prior to handshake which can be used to qualify and reject connections
idle_timeout	Timeout after which a TCP connection is closed by the server.
read_max	maximum size of a single socket read. Defaults to 32K.

Definition at line 50 of file tcp_connection.cc.

References tcp_socket_, and tls_socket_.

◆ ~TcpConnection()

isc::tcp::TcpConnection::~TcpConnection ( )

virtual

Destructor.

Closes current connection.

Definition at line 78 of file tcp_connection.cc.

References close().

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Member Function Documentation

◆ acceptorCallback()

void isc::tcp::TcpConnection::acceptorCallback ( const boost::system::error_code & ec )

protected

Local callback invoked when new connection is accepted.

It invokes external (supplied via constructor) acceptor callback. If the acceptor is not opened it returns immediately. If the connection is accepted successfully the TcpConnection::doRead or TcpConnection::doHandshake is called.

Parameters

ec	Error code.

Definition at line 291 of file tcp_connection.cc.

References acceptor_, acceptor_callback_, connection_filter_, isc::log::DBGLVL_TRACE_DETAIL, doHandshake(), getRemoteEndpointAddressAsText(), idle_timeout_, LOG_DEBUG, NO_ENDPOINT(), isc::tcp::TcpConnectionPool::rejected_counter_, remote_endpoint_, stopThisConnection(), isc::tcp::TCP_CONNECTION_REJECTED_BY_FILTER, isc::tcp::tcp_logger, isc::tcp::TCP_REQUEST_RECEIVE_START, tcp_socket_, isc::tcp::TLS_CONNECTION_HANDSHAKE_START, tls_context_, and tls_socket_.

Referenced by asyncAccept().

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◆ asyncAccept()

void isc::tcp::TcpConnection::asyncAccept ( )

Asynchronously accepts new connection.

When the connection is established successfully, the timeout timer is setup and the asynchronous handshake with client is performed.

Definition at line 150 of file tcp_connection.cc.

References acceptor_, acceptorCallback(), isc_throw, tcp_socket_, tls_socket_, and isc::Exception::what().

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◆ asyncSendResponse()

void isc::tcp::TcpConnection::asyncSendResponse ( TcpResponsePtr response )

protected

Sends TCP response asynchronously.

Internally it calls TcpConnection::doWrite to send the data.

Parameters

response Pointer to the TCP response to be sent.

Definition at line 285 of file tcp_connection.cc.

References doWrite().

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◆ close()

void isc::tcp::TcpConnection::close ( )

virtual

Closes the socket.

Definition at line 109 of file tcp_connection.cc.

References isc::asiolink::IntervalTimer::cancel(), idle_timer_, isc_throw, tcp_socket_, and tls_socket_.

Referenced by ~TcpConnection().

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◆ createRequest()

virtual TcpRequestPtr isc::tcp::TcpConnection::createRequest ( )

pure virtual

Creates a new, empty request.

This function is called by postData(), following the completion of the current request, to create a new request for accepting the next data read.

Returns: Pointer to the new request.

Referenced by doRead(), and postData().

◆ doHandshake()

void isc::tcp::TcpConnection::doHandshake ( )

Asynchronously performs TLS handshake.

When the handshake is performed successfully or skipped because TLS was not enabled, the asynchronous read from the socket is started.

Definition at line 178 of file tcp_connection.cc.

References doRead(), handshakeCallback(), isc_throw, setupIdleTimer(), tls_socket_, and isc::Exception::what().

Referenced by acceptorCallback().

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◆ doRead()

void isc::tcp::TcpConnection::doRead ( TcpRequestPtr request = TcpRequestPtr() )

Starts asynchronous read from the socket.

The data received over the socket are supplied to the TCP parser until the parser signals that the entire request has been received or until the parser signals an error. In the former case the server creates an TCP response using supplied response creator object.

In case of error the connection is stopped.

Parameters

request Pointer to the request for which the read operation should be performed. It defaults to null pointer which indicates that this function should create new request.

Definition at line 203 of file tcp_connection.cc.

References createRequest(), getInputBufData(), getInputBufSize(), setupIdleTimer(), socketReadCallback(), stopThisConnection(), tcp_socket_, and tls_socket_.

Referenced by doHandshake(), handshakeCallback(), and socketReadCallback().

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◆ doWrite()

void isc::tcp::TcpConnection::doWrite ( TcpResponsePtr response )

protected

Starts asynchronous write to the socket.

The output_buf_ must contain the data to be sent.

In case of error the connection is stopped.

Parameters

response Pointer to the response to write operation should be performed.

Definition at line 240 of file tcp_connection.cc.

References isc::log::DBGLVL_TRACE_BASIC, getRemoteEndpointAddressAsText(), LOG_DEBUG, responseSent(), setupIdleTimer(), socketWriteCallback(), stopThisConnection(), isc::tcp::tcp_logger, isc::tcp::TCP_SERVER_RESPONSE_SEND, tcp_socket_, isc::tcp::TLS_SERVER_RESPONSE_SEND, and tls_socket_.

Referenced by asyncSendResponse(), and socketWriteCallback().

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◆ getInputBufData()

unsigned char * isc::tcp::TcpConnection::getInputBufData ( )

inlineprotected

Returns pointer to the first byte of the input buffer.

Exceptions

InvalidOperation if called when the buffer is empty.

Definition at line 412 of file tcp_connection.h.

References input_buf_, and isc_throw.

Referenced by doRead().

◆ getInputBufSize()

size_t isc::tcp::TcpConnection::getInputBufSize ( ) const

inlineprotected

Returns input buffer size.

Definition at line 421 of file tcp_connection.h.

References input_buf_.

Referenced by doRead().

◆ getReadMax()

size_t isc::tcp::TcpConnection::getReadMax ( ) const

inline

Fetches the maximum number of bytes read during single socket read.

Returns: Maximum number of bytes to read.

Definition at line 290 of file tcp_connection.h.

References read_max_.

◆ getRemoteEndpoint()

const boost::asio::ip::tcp::endpoint isc::tcp::TcpConnection::getRemoteEndpoint ( ) const

inline

Fetches the remote endpoint for the connection's socket.

Returns: A reference to the endpoint if the socket is open, otherwise NO_ENDPOINT.

Definition at line 318 of file tcp_connection.h.

References remote_endpoint_.

◆ getRemoteEndpointAddressAsText()

std::string isc::tcp::TcpConnection::getRemoteEndpointAddressAsText ( ) const

protected

returns remote address in textual form

Definition at line 510 of file tcp_connection.cc.

References NO_ENDPOINT(), and remote_endpoint_.

Referenced by acceptorCallback(), doWrite(), handshakeCallback(), idleTimeoutCallback(), postData(), shutdownConnection(), socketReadCallback(), socketWriteCallback(), and stopThisConnection().

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◆ handshakeCallback()

void isc::tcp::TcpConnection::handshakeCallback ( const boost::system::error_code & ec )

protected

Local callback invoked when TLS handshake is performed.

If the handshake is performed successfully the TcpConnection::doRead is called.

Parameters

ec	Error code.

Definition at line 345 of file tcp_connection.cc.

References isc::log::DBGLVL_TRACE_DETAIL, doRead(), getRemoteEndpointAddressAsText(), idle_timeout_, LOG_DEBUG, LOG_INFO, stopThisConnection(), isc::tcp::tcp_logger, isc::tcp::TLS_CONNECTION_HANDSHAKE_FAILED, and isc::tcp::TLS_REQUEST_RECEIVE_START.

Referenced by doHandshake().

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◆ idleTimeoutCallback()

void isc::tcp::TcpConnection::idleTimeoutCallback ( )

protected

Callback invoked when the client has been idle.

Definition at line 499 of file tcp_connection.cc.

References isc::log::DBGLVL_TRACE_DETAIL, getRemoteEndpointAddressAsText(), LOG_DEBUG, stopThisConnection(), isc::tcp::TCP_IDLE_CONNECTION_TIMEOUT_OCCURRED, and isc::tcp::tcp_logger.

Referenced by setupIdleTimer().

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◆ NO_ENDPOINT()

static const boost::asio::ip::tcp::endpoint & isc::tcp::TcpConnection::NO_ENDPOINT ( )

inlinestatic

Returns an empty end point.

Returns: an uninitialized endpoint.

Definition at line 309 of file tcp_connection.h.

Referenced by acceptorCallback(), getRemoteEndpointAddressAsText(), and isc::tcp::TcpConnectionPool::usedByRemoteIpInternal().

◆ postData()

TcpRequestPtr isc::tcp::TcpConnection::postData	(	TcpRequestPtr	request,
		WireData &	input_data
	)

Appends newly received raw data to the given request.

The input data is passed into the current request's postBuffer method. If the request is still incomplete, we return it and wait for more data to post. Otherwise, the request is complete and it is passed into TcpConnection::requestReceived() to be processed. Upon return from that, a new request is created and returned to be used for the next read cycle.

Parameters

request	request to which data should be posted.
input_data	raw data to post.

Returns: Pointer to the request to use for the next read.

Definition at line 403 of file tcp_connection.cc.

References isc::asiolink::IntervalTimer::cancel(), createRequest(), isc::log::DBGLVL_TRACE_BASIC, getRemoteEndpointAddressAsText(), idle_timer_, LOG_DEBUG, LOG_ERROR, postData(), requestReceived(), isc::tcp::TCP_CLIENT_REQUEST_RECEIVED, isc::tcp::tcp_logger, and isc::tcp::TCP_REQUEST_RECEIVED_FAILED.

Referenced by postData(), and socketReadCallback().

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◆ requestReceived()

virtual void isc::tcp::TcpConnection::requestReceived ( TcpRequestPtr request )

pure virtual

Processes a request once it has been completely received.

This function is called by postData() if the post results in a completion (i.e. request's needData() returns false).

Referenced by postData().

◆ responseSent()

virtual bool isc::tcp::TcpConnection::responseSent ( TcpResponsePtr response )

pure virtual

Determines behavior after a response has been sent.

Parameters

response Pointer to the response sent.

Returns: True if the idle timer should be started.

Referenced by doWrite().

◆ setReadMax()

void isc::tcp::TcpConnection::setReadMax ( const size_t read_max )

Sets the maximum number of bytes read during single socket read.

Parameters

read_max maximum number of bytes to read.

Exceptions

BadValue if the parameter is not greater than zero.

Definition at line 519 of file tcp_connection.cc.

References input_buf_, isc_throw, and read_max_.

◆ setupIdleTimer()

void isc::tcp::TcpConnection::setupIdleTimer ( )

protected

Reset timer for detecting idle timeout in connections.

Definition at line 493 of file tcp_connection.cc.

References idle_timeout_, idle_timer_, idleTimeoutCallback(), isc::asiolink::IntervalTimer::ONE_SHOT, and isc::asiolink::IntervalTimer::setup().

Referenced by doHandshake(), doRead(), doWrite(), and socketReadCallback().

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◆ shutdown()

void isc::tcp::TcpConnection::shutdown ( )

virtual

Shutdown the socket.

Definition at line 88 of file tcp_connection.cc.

References isc::asiolink::IntervalTimer::cancel(), idle_timer_, isc_throw, shutdownCallback(), tcp_socket_, and tls_socket_.

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◆ shutdownCallback()

void isc::tcp::TcpConnection::shutdownCallback ( const boost::system::error_code & ec )

protected

Callback invoked when TLS shutdown is performed.

The TLS socket is unconditionally closed but the callback is called only when the peer has answered so the connection should be explicitly closed in all cases, i.e. do not rely on this handler.

Parameters

ec	Error code (ignored).

Definition at line 83 of file tcp_connection.cc.

References tls_socket_.

Referenced by shutdown().

◆ shutdownConnection()

void isc::tcp::TcpConnection::shutdownConnection ( )

protectedvirtual

Shuts down current connection.

Copied from the next method stopThisConnection

Definition at line 126 of file tcp_connection.cc.

References connection_pool_, isc::log::DBGLVL_TRACE_BASIC, getRemoteEndpointAddressAsText(), LOG_DEBUG, LOG_ERROR, isc::tcp::TcpConnectionPool::shutdown(), isc::tcp::TCP_CONNECTION_SHUTDOWN, isc::tcp::TCP_CONNECTION_SHUTDOWN_FAILED, and isc::tcp::tcp_logger.

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◆ socketReadCallback()

void isc::tcp::TcpConnection::socketReadCallback	(	TcpRequestPtr	request,
		boost::system::error_code	ec,
		size_t	length
	)

protected

Callback invoked when new data is received over the socket.

This callback supplies the data to the TCP parser and continues parsing. When the parser signals end of the TCP request the callback prepares a response and starts asynchronous send over the socket.

Parameters

request	Pointer to the request for which the callback is invoked.
ec	Error code.
length	Length of the received data.

Definition at line 361 of file tcp_connection.cc.

References isc::log::DBGLVL_TRACE_DETAIL_DATA, doRead(), getRemoteEndpointAddressAsText(), input_buf_, LOG_DEBUG, postData(), setupIdleTimer(), stopThisConnection(), isc::tcp::TCP_DATA_RECEIVED, and isc::tcp::tcp_logger.

Referenced by doRead().

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◆ socketWriteCallback()

void isc::tcp::TcpConnection::socketWriteCallback	(	TcpResponsePtr	request,
		boost::system::error_code	ec,
		size_t	length
	)

protectedvirtual

Callback invoked when data is sent over the socket.

Parameters

request	Pointer to the request for which the callback is invoked.
ec	Error code.
length	Length of the data sent.

Definition at line 448 of file tcp_connection.cc.

References isc::log::DBGLVL_TRACE_DETAIL_DATA, doWrite(), getRemoteEndpointAddressAsText(), LOG_DEBUG, stopThisConnection(), isc::tcp::TCP_DATA_SENT, and isc::tcp::tcp_logger.

Referenced by doWrite().

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◆ stopThisConnection()

void isc::tcp::TcpConnection::stopThisConnection ( )

protectedvirtual

Stops current connection.

Definition at line 138 of file tcp_connection.cc.

References connection_pool_, isc::log::DBGLVL_TRACE_BASIC, getRemoteEndpointAddressAsText(), LOG_DEBUG, LOG_ERROR, isc::tcp::TcpConnectionPool::stop(), isc::tcp::TCP_CONNECTION_STOP, isc::tcp::TCP_CONNECTION_STOP_FAILED, and isc::tcp::tcp_logger.

Referenced by acceptorCallback(), doRead(), doWrite(), handshakeCallback(), idleTimeoutCallback(), socketReadCallback(), and socketWriteCallback().

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Member Data Documentation

◆ acceptor_

TcpConnectionAcceptorPtr isc::tcp::TcpConnection::acceptor_

protected

Pointer to the TCP acceptor used to accept new connections.

Definition at line 445 of file tcp_connection.h.

Referenced by acceptorCallback(), and asyncAccept().

◆ acceptor_callback_

TcpConnectionAcceptorCallback isc::tcp::TcpConnection::acceptor_callback_

protected

External TCP acceptor callback.

Definition at line 451 of file tcp_connection.h.

Referenced by acceptorCallback().

◆ connection_filter_

TcpConnectionFilterCallback isc::tcp::TcpConnection::connection_filter_

protected

External callback for filtering connections by IP address.

Definition at line 454 of file tcp_connection.h.

Referenced by acceptorCallback().

◆ connection_pool_

TcpConnectionPool& isc::tcp::TcpConnection::connection_pool_

protected

Connection pool holding this connection.

Definition at line 448 of file tcp_connection.h.

Referenced by shutdownConnection(), and stopThisConnection().

◆ idle_timeout_

long isc::tcp::TcpConnection::idle_timeout_

protected

Timeout after which the a TCP connection is shut down by the server.

Definition at line 433 of file tcp_connection.h.

Referenced by acceptorCallback(), handshakeCallback(), and setupIdleTimer().

◆ idle_timer_

asiolink::IntervalTimer isc::tcp::TcpConnection::idle_timer_

protected

Timer used to detect idle Timeout.

Definition at line 436 of file tcp_connection.h.

Referenced by close(), postData(), setupIdleTimer(), and shutdown().

◆ input_buf_

WireData isc::tcp::TcpConnection::input_buf_

protected

Buffer for a single socket read.

Definition at line 460 of file tcp_connection.h.

Referenced by getInputBufData(), getInputBufSize(), setReadMax(), and socketReadCallback().

◆ io_service_

asiolink::IOServicePtr isc::tcp::TcpConnection::io_service_

protected

The IO service used to handle events.

Definition at line 426 of file tcp_connection.h.

◆ read_max_

size_t isc::tcp::TcpConnection::read_max_

protected

Maximum bytes to read in a single socket read.

Definition at line 457 of file tcp_connection.h.

Referenced by getReadMax(), and setReadMax().

◆ remote_endpoint_

boost::asio::ip::tcp::endpoint isc::tcp::TcpConnection::remote_endpoint_

protected

Remote endpoint.

Definition at line 463 of file tcp_connection.h.

Referenced by acceptorCallback(), getRemoteEndpoint(), and getRemoteEndpointAddressAsText().

◆ tcp_socket_

std::unique_ptr<asiolink::TCPSocket<SocketCallback> > isc::tcp::TcpConnection::tcp_socket_

protected

TCP socket used by this connection.

Definition at line 439 of file tcp_connection.h.

Referenced by TcpConnection(), acceptorCallback(), asyncAccept(), close(), doRead(), doWrite(), and shutdown().

◆ tls_context_

asiolink::TlsContextPtr isc::tcp::TcpConnection::tls_context_

protected

TLS context.

Definition at line 429 of file tcp_connection.h.

Referenced by acceptorCallback().

◆ tls_socket_

std::unique_ptr<asiolink::TLSSocket<SocketCallback> > isc::tcp::TcpConnection::tls_socket_

protected

TLS socket used by this connection.

Definition at line 442 of file tcp_connection.h.

Referenced by TcpConnection(), acceptorCallback(), asyncAccept(), close(), doHandshake(), doRead(), doWrite(), shutdown(), and shutdownCallback().

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

Public Member Functions

Static Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ TcpConnection()

◆ ~TcpConnection()

Member Function Documentation

◆ acceptorCallback()

◆ asyncAccept()

◆ asyncSendResponse()

◆ close()

◆ createRequest()

◆ doHandshake()

◆ doRead()

◆ doWrite()

◆ getInputBufData()

◆ getInputBufSize()

◆ getReadMax()

◆ getRemoteEndpoint()

◆ getRemoteEndpointAddressAsText()

◆ handshakeCallback()

◆ idleTimeoutCallback()

◆ NO_ENDPOINT()

◆ postData()

◆ requestReceived()

◆ responseSent()

◆ setReadMax()

◆ setupIdleTimer()

◆ shutdown()

◆ shutdownCallback()

◆ shutdownConnection()

◆ socketReadCallback()

◆ socketWriteCallback()

◆ stopThisConnection()

Member Data Documentation

◆ acceptor_

◆ acceptor_callback_

◆ connection_filter_

◆ connection_pool_

◆ idle_timeout_

◆ idle_timer_

◆ input_buf_

◆ io_service_

◆ read_max_

◆ remote_endpoint_

◆ tcp_socket_

◆ tls_context_

◆ tls_socket_