Base class for a TCP/IP session. More...

#include <tsTCPConnection.h>

Inheritance diagram for ts::TCPConnection:

[legend]

Collaboration diagram for ts::TCPConnection:

[legend]

Public Types
using	SuperClass = TCPSocket
	Reference to the superclass.

Public Member Functions
	TCPConnection (Report *report=nullptr, bool non_blocking=false)
	Constructor.

	TCPConnection (ReporterBase *delegate, bool non_blocking=false)
	Constructor.

void	addSubscription (SocketHandlerInterface *handler)
	Add a subscriber to open/close events.

bool	bind (const IPSocketAddress &addr)
	Bind to a local address and port.

void	cancelSubscription (SocketHandlerInterface *handler)
	Remove a subscriber to open/close events.

virtual bool	close (bool silent=false) override
	Close the socket.

virtual bool	closeWriter (bool silent=false)
	Close the write direction of the connection.

virtual bool	connect (const IPSocketAddress &addr, IOSB *iosb=nullptr)
	Connect to a remote address and port.

virtual bool	disconnect (bool silent=false)
	Disconnect from remote partner.

IP	generation () const
	Get the IP generation with which the socket was open.

bool	getLocalAddress (IPSocketAddress &addr) const
	Get local socket address.

bool	getPeer (IPSocketAddress &addr)
	Get the connected remote peer.

SysSocketType	getSocket () const
	Get the underlying socket device handle (use with care).

bool	isConnected () const
	Check if the socket is connected.

bool	isNonBlocking () const
	Check if the device is in non-blocking mode.

bool	isOpen () const
	Check if socket is open.

bool	muteReport (bool mute)
	Temporarily mute the associated report.

virtual bool	open (IP gen) override
	Open the socket.

UString	peerName ()
	Get the connected remote peer as a string.

virtual bool	receive (void buffer, size_t max_size, size_t &ret_size, const AbortInterface abort=nullptr, IOSB *iosb=nullptr)
	Receive data.

virtual bool	receive (void buffer, size_t size, const AbortInterface abort=nullptr)
	Receive data until buffer is full.

Report &	report () const
	Access the Report which is associated with this object.

bool	reusePort (bool reuse_port)
	Set the "reuse port" option.

virtual bool	send (const void data, size_t size, IOSB iosb=nullptr)
	Send data.

bool	setKeepAlive (bool active)
	Set the "keep alive" option.

bool	setLingerTime (int seconds)
	Set the linger time option.

bool	setNoDelay (bool active)
	Set the "no delay" option.

bool	setNoLinger ()
	Remove the linger time option.

bool	setNonBlocking (bool non_blocking)
	Set the device in non-blocking mode.

bool	setReceiveBufferSize (size_t size)
	Set the receive buffer size.

bool	setReceiveTimeout (cn::milliseconds timeout)
	Set the receive timeout.

Report *	setReport (Report *report)
	Associate this object with another Report to log errors.

ReporterBase *	setReport (ReporterBase *delegate)
	Associate this object with another ReporterBase to log errors.

bool	setSendBufferSize (size_t size)
	Set the send buffer size.

bool	setTTL (int ttl)
	Set the Time To Live (TTL) option.

Static Public Member Functions
static int	SilentLevel (bool silent)
	Compute a log severity level from a "silent" parameter.

Protected Member Functions
virtual bool	allowSetNonBlocking () const override
	Check that the non-blocking mode can be set.

bool	checkNonBlocking (bool non_blocking, const UChar *opname)
	Check the blocking mode of a device.

bool	checkNonBlocking (IOSB iosb, const UChar opname)
	Check the blocking mode of a device.

bool	convert (IPAddress &addr) const
	Convert an IP address to make it compatible with the socket IP generation.

bool	createSocket (IP gen, int type, int protocol)
	Create the socket.

virtual void	declareOpened (SysSocketType sock) override
	Set an open socket descriptor from a subclass.

virtual void	handleClosed () override
	This virtual method can be overriden by subclasses to be notified of close.

virtual void	handleConnected ()
	This virtual method can be overriden by subclasses to be notified of connection.

virtual void	handleDisconnected ()
	This virtual method can be overriden by subclasses to be notified of disconnection.

virtual void	handleOpened ()
	This virtual method can be overriden by subclasses to be notified of open.

bool	setSystemNonBlocking (SysSocketType fd, bool non_blocking)
	Convenience method to set a system file descriptor or socket handle in non-blocking mode.

Protected Attributes
std::recursive_mutex	_mutex {}
	Mutex protecting this object.

Detailed Description

Base class for a TCP/IP session.

This class can be used directly by applications or can be derived to create specific sub-classes which handle application protocols.

This class is used in two contexts:

A TCP/IP client creates a TCPConnection instance and connects to a server.
A TCP/IP server creates a TCPServer instance and waits for clients. For each client session, a TCPConnection instance is created.

For a detailed scenario of the server side, see the class TCPServer.

The following lists the typical client-side scenario in the correct order. Many steps such as setting socket options are optional. The symbol [*] means mandatory. Depending on the platform, some options settings are sensitive to the order. The following order has proven to work on most platforms.

Invoking close() is optional since the destructor of the class will properly close the socket if not already done. Invoking disconnect() is also optional but is highly recommended. Closing a socket without prior disconnect is considered as a session abort by the remote peer. The peer may thus consider that something went wrong may take unexpected corrective or rollback actions.

Constructor & Destructor Documentation

◆ TCPConnection() [1/2]

ts::TCPConnection::TCPConnection	(	Report *	report = `nullptr`,
		bool	non_blocking = `false`
	)

inlineexplicit

Constructor.

Parameters

[in]	report	Where to report errors. The report object must remain valid as long as this object exists or setReport() is used with another Report object. If report is null, log messages are discarded.
[in]	non_blocking	It true, the device is initially set in non-blocking mode.

◆ TCPConnection() [2/2]

ts::TCPConnection::TCPConnection	(	ReporterBase *	delegate,
		bool	non_blocking = `false`
	)

inlineexplicit

Constructor.

Parameters

[in]	delegate	Use the report of another ReporterBase. If delegate is null, log messages are discarded.
[in]	non_blocking	It true, the device is initially set in non-blocking mode.

Member Function Documentation

◆ connect()

virtual bool ts::TCPConnection::connect	(	const IPSocketAddress &	addr,
		IOSB *	iosb = `nullptr`
	)

virtual

Connect to a remote address and port.

Use this method when acting as TCP client. Do not use on server side: the TCPConnection object is passed to TCPServer::accept() which establishes the connection.

Parameters

[in]	addr	IP address and port of the server to connect.
[in,out]	iosb	Address of an IOSB structure. If non-null, the socket must be in non-blocking mode. When null, the socket must be in blocking mode (the default). See the description of IOSB. Important: The parameter iosb should not be used by applications. It should be used only by "reactive classes", which work in combination with a Reactor.

Returns: True on success, false on error.

Reimplemented in ts::TLSConnection.

◆ isConnected()

bool ts::TCPConnection::isConnected ( ) const

inline

Check if the socket is connected.

Returns: True if the socket was successfully connected to the peer.

◆ getPeer()

bool ts::TCPConnection::getPeer ( IPSocketAddress & addr )

Get the connected remote peer.

Parameters

[out] addr IP address and port of the remote socket.

Returns: True on success, false on error.

◆ peerName()

UString ts::TCPConnection::peerName ( )

Get the connected remote peer as a string.

Returns: A string representation of the IP address and port of the remote socket.

◆ closeWriter()

virtual bool ts::TCPConnection::closeWriter ( bool silent = false )

virtual

Close the write direction of the connection.

The application shall call this routine after sending the last message but may still want to receive messages, waiting for the peer to voluntary disconnect.

Parameters

[in] silent If true, do not report errors through the logger. This is typically useful when the socket is in some error condition and closing it is necessary although it may generate additional meaningless errors.

Returns: True on success, false on error.

Reimplemented in ts::TLSConnection.

◆ disconnect()

virtual bool ts::TCPConnection::disconnect ( bool silent = false )

virtual

Disconnect from remote partner.

Parameters

[in] silent If true, do not report errors through the logger. This is typically useful when the socket is in some error condition and closing it is necessary although it may generate additional meaningless errors.

Returns: True on success, false on error.

Reimplemented in ts::TLSConnection.

◆ send()

virtual bool ts::TCPConnection::send	(	const void *	data,
		size_t	size,
		IOSB *	iosb = `nullptr`
	)

virtual

Send data.

Parameters

[in]	data	Address of the data to send.
[in]	size	Size in bytes of the data to send.
[in,out]	iosb	Address of an IOSB structure. If non-null, the socket must be in non-blocking mode. When null, the socket must be in blocking mode (the default). See the description of IOSB. Important: The parameter iosb should not be used by applications. It should be used only by "reactive classes", which work in combination with a Reactor.

Returns: True on success, false on error.

Reimplemented in ts::TLSConnection.

◆ receive() [1/2]

virtual bool ts::TCPConnection::receive	(	void *	buffer,
		size_t	max_size,
		size_t &	ret_size,
		const AbortInterface *	abort = `nullptr`,
		IOSB *	iosb = `nullptr`
	)

virtual

Receive data.

This version of receiveMessage() returns when "some" data are received into the user buffer. The actual received data may be shorter than the user buffer size.

The version is typically useful when the application cannot predict how much data will be received and must respond even if the user buffer is not full.

Parameters

[out]	buffer	Address of the buffer for the received data.
[in]	max_size	Size in bytes of the reception buffer.
[out]	ret_size	Size in bytes of the received data. Will never be larger than max_size.
[in]	abort	If non-zero, invoked when I/O is interrupted (in case of user-interrupt, return, otherwise retry).
[in,out]	iosb	Address of an IOSB structure. If non-null, the socket must be in non-blocking mode. When null, the socket must be in blocking mode (the default). See the description of IOSB. Important: The parameter iosb should not be used by applications. It should be used only by "reactive classes", which work in combination with a Reactor.

Returns: True on success, false on error.

Reimplemented in ts::TLSConnection.

◆ receive() [2/2]

virtual bool ts::TCPConnection::receive	(	void *	buffer,
		size_t	size,
		const AbortInterface *	abort = `nullptr`
	)

virtual

Receive data until buffer is full.

This version of receive() returns only when sufficient data are received to completely fill the user buffer. The size of the actual received data is identical to the user buffer size. If some data, but not all, were received before the connection was closed, these data are ignored and the method returns false. The version is typically useful when the application knows that a certain amount of data is expected and must wait for them.

This method is only allowed when the socket is in blocking-mode (the default) because this method is blocking by definition. Therefore, there is no iosb parameter.

This base implementation uses the variable-length version of receive(). Therefore, a subclass may only override the variable-length version and not this one.

Parameters

[out]	buffer	Address of the buffer for the received data.
[in]	size	Size in bytes of the buffer.
[in]	abort	If non-zero, invoked when I/O is interrupted (in case of user-interrupt, return, otherwise retry).

Returns: True on success, false on error.

Reimplemented in ts::TLSConnection.

◆ handleConnected()

virtual void ts::TCPConnection::handleConnected ( )

protectedvirtual

This virtual method can be overriden by subclasses to be notified of connection.

All subclasses should explicitly invoke their superclass' handlers.

Reimplemented in ts::tlv::Connection< SAFETY >, ts::tlv::Connection< ThreadSafety::Full >, and ts::tlv::Connection< ThreadSafety::None >.

◆ handleDisconnected()

virtual void ts::TCPConnection::handleDisconnected ( )

protectedvirtual

This virtual method can be overriden by subclasses to be notified of disconnection.

All subclasses should explicitly invoke their superclass' handlers.

◆ handleClosed()

virtual void ts::TCPConnection::handleClosed ( )

overrideprotectedvirtual

This virtual method can be overriden by subclasses to be notified of close.

All subclasses should explicitly invoke their superclass' handlers.

Reimplemented from ts::TCPSocket.

◆ setTTL()

bool ts::TCPSocket::setTTL ( int ttl )

inherited

Set the Time To Live (TTL) option.

Parameters

[in] ttl The TTL value, ie. the maximum number of "hops" between routers before an IP packet is dropped.

Returns: True on success, false on error.

◆ setNoLinger()

bool ts::TCPSocket::setNoLinger ( )

inherited

Remove the linger time option.

Returns: True on success, false on error.

◆ setLingerTime()

bool ts::TCPSocket::setLingerTime ( int seconds )

inherited

Set the linger time option.

Parameters

[in] seconds Number of seconds to wait after shuting down the socket.

Returns: True on success, false on error.

◆ setKeepAlive()

bool ts::TCPSocket::setKeepAlive ( bool active )

inherited

Set the "keep alive" option.

Parameters

[in] active If true, the socket periodically sends "keep alive" packets when the connection is idle.

Returns: True on success, false on error.

◆ setNoDelay()

bool ts::TCPSocket::setNoDelay ( bool active )

inherited

Set the "no delay" option.

Parameters

[in] active If true, the socket immediately sends outgoing packets. By default, a TCP socket waits a small amount of time after a send() operation to get a chance to group outgoing data from successive send() operations into one single packet.

Returns: True on success, false on error.

◆ open()

virtual bool ts::TCPSocket::open ( IP gen )

overridevirtualinherited

Open the socket.

Parameters

[in] gen IP generation, IPv4 or IPv6. If set to IP::Any, open an IPv6 socket (IPv4 connections allowed).

Returns: True on success, false on error.

Implements ts::Socket.

◆ close()

virtual bool ts::TCPSocket::close ( bool silent = false )

overridevirtualinherited

Close the socket.

If overridden by a subclass, the superclass must be called at the end of the overridden close().

Parameters

[in] silent If true, do not report errors through the logger. This is typically useful when the socket is in some error condition and closing it is necessary although it may generate additional meaningless errors.

Returns: True on success, false on error.

Reimplemented from ts::Socket.

Reimplemented in ts::TCPServer, and ts::TLSServer.

◆ handleOpened()

virtual void ts::TCPSocket::handleOpened ( )

protectedvirtualinherited

This virtual method can be overriden by subclasses to be notified of open.

All subclasses should explicitly invoke their superclass' handlers.

◆ declareOpened()

virtual void ts::TCPSocket::declareOpened ( SysSocketType sock )

overrideprotectedvirtualinherited

Set an open socket descriptor from a subclass.

This method is used by a server to declare that a client socket has just become opened.

Parameters

[in] sock New socket descriptor.

Reimplemented from ts::Socket.

◆ isOpen()

bool ts::Socket::isOpen ( ) const

inlineinherited

Check if socket is open.

Returns: True if socket is open.

◆ generation()

IP ts::Socket::generation ( ) const

inlineinherited

Get the IP generation with which the socket was open.

Returns: The IP generation used to open the socket. Never IP::Any.

◆ setSendBufferSize()

bool ts::Socket::setSendBufferSize ( size_t size )

inherited

Set the send buffer size.

Parameters

[in] size Send buffer size in bytes.

Returns: True on success, false on error.

◆ setReceiveBufferSize()

bool ts::Socket::setReceiveBufferSize ( size_t size )

inherited

Set the receive buffer size.

Parameters

[in] size Receive buffer size in bytes.

Returns: True on success, false on error.

◆ setReceiveTimeout()

bool ts::Socket::setReceiveTimeout ( cn::milliseconds timeout )

inherited

Set the receive timeout.

Parameters

[in] timeout Receive timeout in milliseconds. If negative or zero, receive timeout is not used, reception waits forever.

Returns: True on success, false on error.

◆ reusePort()

bool ts::Socket::reusePort ( bool reuse_port )

inherited

Set the "reuse port" option.

Parameters

[in] reuse_port If true, the socket is allowed to reuse a local UDP port which is already bound.

Returns: True on success, false on error.

◆ bind()

bool ts::Socket::bind ( const IPSocketAddress & addr )

inherited

Bind to a local address and port.

The IP address part of the socket address must one of:

IPAddress::AnyAddress4.
- UDP: Any local interface may be used to send or receive UDP datagrams. For each outgoing packet, the actual interface is selected by the kernel based on the routing rules. Incoming UDP packets for the selected port will be accepted from any local interface.
- TCP client: Any local interface may be used to connect to a server.
- TCP server: Any local interface may be used to receive incoming client connections.
The IP address of an interface of the local system.
- UDP: Outgoing packets will be unconditionally sent through this interface. Incoming UDP packets for the selected port will be accepted only when they arrive through the selected interface.
- TCP client: Outgoing connections will be only allowed through this interface.
- TCP server: Incoming client connections will be accepted only when they arrive through the selected interface.

Special note for receiving multicast on most Unix systems (at least Linux and macOS): The IP address shall be either AnyAddress4 or the multicast group address. Do not specify a local address to receive multicast on Unix.

The port number part of the socket address must be one of:

IPSocketAddress::AnyPort. The socket is bound to an arbitrary unused local UDP or TCP port. This is the usual configuration for a TCP client.
A specific port number. If this UDP or TCP port is already bound by another local socket of the same type, the bind operation fails, unless the "reuse port" option has already been set.

Parameters

[in] addr Local socket address to bind to.

Returns: True on success, false on error.

◆ getLocalAddress()

bool ts::Socket::getLocalAddress ( IPSocketAddress & addr ) const

inherited

Get local socket address.

Parameters

[out] addr Local socket address of the connection.

Returns: True on success, false on error.

◆ getSocket()

SysSocketType ts::Socket::getSocket ( ) const

inlineinherited

Get the underlying socket device handle (use with care).

This method is reserved for low-level operations and should not be used by normal applications.

Returns: The underlying socket system device handle or file descriptor. Return SYS_SOCKET_INVALID if the socket is not open.

◆ addSubscription()

void ts::Socket::addSubscription ( SocketHandlerInterface * handler )

inherited

Add a subscriber to open/close events.

Parameters

[in] handler The object to call on open() and close().

◆ cancelSubscription()

void ts::Socket::cancelSubscription ( SocketHandlerInterface * handler )

inherited

Remove a subscriber to open/close events.

Parameters

[in] handler The object to no longer call on open() and close().

◆ createSocket()

bool ts::Socket::createSocket	(	IP	gen,
		int	type,
		int	protocol
	)

protectedinherited

Create the socket.

Parameters

[in]	gen	IP generation.
[in]	type	Socket type: SOCK_STREAM, SOCK_DGRAM
[in]	protocol	Socket protocol: IPPROTO_TCP, IPPROTO_UDP

Returns: True on success, false on error.

See also: open(ge, Report&)

◆ convert()

bool ts::Socket::convert ( IPAddress & addr ) const

protectedinherited

Convert an IP address to make it compatible with the socket IP generation.

Parameters

addr	[in,out] The address to convert.

Returns: True on success, false on error.

◆ allowSetNonBlocking()

virtual bool ts::Socket::allowSetNonBlocking ( ) const

overrideprotectedvirtualinherited

Check that the non-blocking mode can be set.

Must be implemented by subclasses which do not support setting the non-blocking in certain states, such as after being opened. The default implementation always allows setting the non-blocking mode.

Returns: True if setting the non-blocking mode is allowed, false otherwise.

Reimplemented from ts::NonBlockingDevice.

◆ setNonBlocking()

bool ts::NonBlockingDevice::setNonBlocking ( bool non_blocking )

inherited

Set the device in non-blocking mode.

Important: Usually, this method must be called before opening the device, whatever it means. Otherwise it is ignored and the device blocking mode is unchanged.

Parameters

[in] non_blocking It true, the device is set in non-blocking mode.

Returns: True on success, false if the device is already open and the non-blocking mode is unchanged.

◆ isNonBlocking()

bool ts::NonBlockingDevice::isNonBlocking ( ) const

inlineinherited

Check if the device is in non-blocking mode.

Returns: True if the device is in non-blocking mode, false otherwise.

See also: setNonBlocking()

◆ checkNonBlocking() [1/2]

bool ts::NonBlockingDevice::checkNonBlocking	(	bool	non_blocking,
		const UChar *	opname
	)

protectedinherited

Check the blocking mode of a device.

Called by subclass methods which are explicitly called in blocking or non-blocking mode.

Parameters

[in]	non_blocking	The required non-blocking mode.
[in]	opname	Name of the operation, for the error message.

Returns: True on success, false on error.

◆ checkNonBlocking() [2/2]

bool ts::NonBlockingDevice::checkNonBlocking	(	IOSB *	iosb,
		const UChar *	opname
	)

protectedinherited

Check the blocking mode of a device.

Called by subclass methods which are explicitly called in blocking or non-blocking mode.

Parameters

[in,out]	iosb	Address of an IOSB structure. If non-null, we are in non-blocking mode. When null, we are in blocking mode. When non-null, pending is reset to false and overlap is zeroed.
[in]	opname	Name of the operation, for the error message.

Returns: True on success, false on error.

◆ setSystemNonBlocking()

bool ts::NonBlockingDevice::setSystemNonBlocking	(	SysSocketType	fd,
		bool	non_blocking
	)

protectedinherited

Convenience method to set a system file descriptor or socket handle in non-blocking mode.

Parameters

[in]	fd	System file descriptor (UNIX) or socket handle (Windows). On Windows, non-socket devices shall be opened with flag FILE_FLAG_OVERLAPPED instead of using this method.
[in]	non_blocking	It true, the device is set in non-blocking mode.

Returns: True on success, false on error.

◆ report()

Report & ts::ReporterBase::report ( ) const

inherited

Access the Report which is associated with this object.

Can be called from another thread only if the Report object is thread-safe.

Returns: A reference to the associated report.

◆ setReport() [1/2]

Report * ts::ReporterBase::setReport ( Report * report )

inherited

Associate this object with another Report to log errors.

Parameters

[in] report Where to report errors. The report object must remain valid as long as this object exists or setReport() is used with another Report object. If report is null, log messages are discarded.

Returns: The address of the previous Report object or a null pointer if there was none.

◆ setReport() [2/2]

ReporterBase * ts::ReporterBase::setReport ( ReporterBase * delegate )

inherited

Associate this object with another ReporterBase to log errors.

Parameters

[in] delegate Use the report of another ReporterBase. If delegate is null, the previous explicit Report is used..

Returns: The address of the previous ReporterBase object or a null pointer if there was none.

◆ muteReport()

bool ts::ReporterBase::muteReport ( bool mute )

inherited

Temporarily mute the associated report.

Parameters

[in] mute It true, report() will return a null report (log messages are discarded), until muteReport() is invoked again with mute set to false.

Returns: Previous state of the mute field.

◆ SilentLevel()

static int ts::ReporterBase::SilentLevel ( bool silent )

inlinestaticinherited

Compute a log severity level from a "silent" parameter.

Some subclass methods have a "silent" parameter to avoid reporting errors which may be insignificant, typically when closing a device after an error, in which case the close operation may produce other errors if the previous error left the device in an inconsistent state. While those errors should not be displayed as errors, we still display them at debug level.

Parameters

[in] silent If true, do not report errors, report debug messages instead.

Returns: Error when silent is false, Debug otherwise.

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

tsTCPConnection.h

Public Types

Public Member Functions

Static Public Member Functions

Protected Member Functions

Protected Attributes

Detailed Description

Constructor & Destructor Documentation

◆ TCPConnection() [1/2]

◆ TCPConnection() [2/2]

Member Function Documentation

◆ connect()

◆ isConnected()

◆ getPeer()

◆ peerName()

◆ closeWriter()

◆ disconnect()

◆ send()

◆ receive() [1/2]

◆ receive() [2/2]

◆ handleConnected()

◆ handleDisconnected()

◆ handleClosed()

◆ setTTL()

◆ setNoLinger()

◆ setLingerTime()

◆ setKeepAlive()

◆ setNoDelay()

◆ open()

◆ close()

◆ handleOpened()

◆ declareOpened()

◆ isOpen()

◆ generation()

◆ setSendBufferSize()

◆ setReceiveBufferSize()

◆ setReceiveTimeout()

◆ reusePort()

◆ bind()

◆ getLocalAddress()

◆ getSocket()

◆ addSubscription()

◆ cancelSubscription()

◆ createSocket()

◆ convert()

◆ allowSetNonBlocking()

◆ setNonBlocking()

◆ isNonBlocking()

◆ checkNonBlocking() [1/2]

◆ checkNonBlocking() [2/2]

◆ setSystemNonBlocking()

◆ report()

◆ setReport() [1/2]

◆ setReport() [2/2]

◆ muteReport()

◆ SilentLevel()