A class for handling exiting TCP connections. More...

#include <AsyncTcpConnection.h>

Inheritance diagram for Async::TcpConnection:

Classes
struct	if_all_true_acc
	A sigc return value accumulator for signals returning bool. More...

Public Types
enum	DisconnectReason { DR_HOST_NOT_FOUND , DR_REMOTE_DISCONNECTED , DR_SYSTEM_ERROR , DR_ORDERED_DISCONNECT , DR_PROTOCOL_ERROR , DR_SWITCH_PEER , DR_BAD_STATE }
	Reason code for disconnects. More...

Public Member Functions
	TcpConnection (size_t recv_buf_len=DEFAULT_RECV_BUF_LEN)
	Constructor.

	TcpConnection (int sock, const IpAddress &remote_addr, uint16_t remote_port, size_t recv_buf_len=DEFAULT_RECV_BUF_LEN)
	Constructor.

virtual	~TcpConnection (void)
	Destructor.

virtual TcpConnection &	operator= (TcpConnection &&other)
	Move assignmnt operator.

void	setRecvBufLen (size_t recv_buf_len)
	Set a new receive buffer size.

size_t	recvBufLen (void) const

virtual void	disconnect (void)
	Disconnect from the remote host.

virtual int	write (const void *buf, int count)
	Write data to the TCP connection.

IpAddress	localHost (void) const
	Get the local IP address associated with this connection.

uint16_t	localPort (void) const
	Get the local TCP port associated with this connection.

const IpAddress &	remoteHost (void) const
	Return the IP-address of the remote host.

uint16_t	remotePort (void) const
	Return the remote port used.

bool	isConnected (void) const
	Check if the connection is established or not.

bool	isIdle (void) const
	Check if the connection is idle.

void	enableSsl (bool enable)
	Enable or disable TLS for this connection.

SslX509	sslPeerCertificate (void)
	Get the peer certificate associated with this connection.

Async::SslX509	sslCertificate (void) const

long	sslVerifyResult (void) const
	Get the result of the certificate verification process.

void	setSslContext (SslContext &ctx, bool is_server)
	Set the OpenSSL context to use when setting up the connection.

SslContext *	sslContext (void)

bool	isServer (void) const

void	freeze (void)
	Stop all communication.

void	unfreeze (void)
	Reenable all communication.

Static Public Member Functions
static const char *	disconnectReasonStr (DisconnectReason reason)
	Translate disconnect reason to a string.

Public Attributes
sigc::signal< void, TcpConnection *, DisconnectReason >	disconnected
	Get common name for the SSL connection.

sigc::signal< int, TcpConnection , void , int >	dataReceived
	A signal that is emitted when data has been received on the connection.

sigc::signal< if_all_true_acc::result_type, TcpConnection , int, X509_STORE_CTX >::accumulated< if_all_true_acc >	verifyPeer
	A signal that is emitted on SSL/TLS certificate verification.

sigc::signal< void, TcpConnection * >	sslConnectionReady
	A signal that is emitted when the SSL connection is ready.

Static Public Attributes
static const int	DEFAULT_RECV_BUF_LEN = 1024
	The default size of the reception buffer.

Protected Member Functions
void	setSocket (int sock)
	Setup information about the connection.

void	setRemoteAddr (const IpAddress &remote_addr)
	Setup information about the connection.

void	setRemotePort (uint16_t remote_port)
	Setup information about the connection.

int	socket (void) const
	Return the socket file descriptor.

virtual void	closeConnection (void)
	Disconnect from the remote peer.

virtual void	onDisconnected (DisconnectReason reason)
	Called when a connection has been terminated.

virtual int	onDataReceived (void *buf, int count)
	Called when data has been received on the connection.

virtual void	emitDisconnected (DisconnectReason reason)
	Emit the disconnected signal.

virtual int	emitVerifyPeer (int preverify_ok, X509_STORE_CTX *store_ctx)
	Emit the verifyPeer signal.

Friends
class	TcpClientBase

Detailed Description

A class for handling exiting TCP connections.

Author: Tobias Blomberg

Date: 2003-12-07

This class is used to handle an existing TCP connection. It is not meant to be used directly but could be. It it mainly created to handle connections for Async::TcpClient and Async::TcpServer.

It can also handle SSL/TLS connections. A raw TCP connection can be switched to be encrypted using the setSslContext() and enableSsl() functions.

The reception buffer size given at construction time or using the setRecvBufLen() function is an initial value. If during the connection a larger buffer is needed the size will be automatically increased.

Examples: AsyncTcpClient_demo.cpp, AsyncTcpPrioClient_demo.cpp, and AsyncTcpServer_demo.cpp.

Definition at line 138 of file AsyncTcpConnection.h.

Member Enumeration Documentation

◆ DisconnectReason

enum Async::TcpConnection::DisconnectReason

Reason code for disconnects.

Enumerator
DR_HOST_NOT_FOUND	The specified host was not found in the DNS.
DR_REMOTE_DISCONNECTED	The remote host disconnected.
DR_SYSTEM_ERROR	A system error occured (check errno)
DR_ORDERED_DISCONNECT	Disconnect ordered locally.
DR_PROTOCOL_ERROR	Protocol error.
DR_SWITCH_PEER	A better peer was found so reconnecting.
DR_BAD_STATE	The connection ended up in a bad state.

Definition at line 144 of file AsyncTcpConnection.h.

Constructor & Destructor Documentation

◆ TcpConnection() [1/2]

Async::TcpConnection::TcpConnection ( size_t recv_buf_len = DEFAULT_RECV_BUF_LEN )

explicit

Constructor.

Parameters

recv_buf_len The initial size of the receive buffer

◆ TcpConnection() [2/2]

Async::TcpConnection::TcpConnection	(	int	sock,
		const IpAddress &	remote_addr,
		uint16_t	remote_port,
		size_t	recv_buf_len = DEFAULT_RECV_BUF_LEN )

Constructor.

Parameters

sock	The socket for the connection to handle
remote_addr	The remote IP-address of the connection
remote_port	The remote TCP-port of the connection
recv_buf_len	The initial size of the receive buffer

◆ ~TcpConnection()

virtual Async::TcpConnection::~TcpConnection ( void )

virtual

Destructor.

Member Function Documentation

◆ closeConnection()

virtual void Async::TcpConnection::closeConnection ( void )

protectedvirtual

Disconnect from the remote peer.

This function is used internally to close the connection to the remote peer.

Reimplemented in Async::FramedTcpConnection, Async::HttpServerConnection, Async::TcpClient< ConT >, and Async::TcpPrioClient< ConT >.

Referenced by disconnect().

◆ disconnect()

virtual void Async::TcpConnection::disconnect ( void )

inlinevirtual

Disconnect from the remote host.

Call this function to disconnect from the remote host. If already disconnected, nothing will be done. The disconnected signal is not emitted when this function is called

Reimplemented in Async::TcpClient< ConT >, and Async::TcpPrioClient< ConT >.

Definition at line 238 of file AsyncTcpConnection.h.

References closeConnection().

◆ disconnectReasonStr()

static const char * Async::TcpConnection::disconnectReasonStr ( DisconnectReason reason )

static

Translate disconnect reason to a string.

Examples: AsyncHttpServer_demo.cpp, and AsyncTcpPrioClient_demo.cpp.

◆ emitDisconnected()

virtual void Async::TcpConnection::emitDisconnected ( DisconnectReason reason )

inlineprotectedvirtual

Emit the disconnected signal.

Parameters

reason The reason for the disconnection

Reimplemented in Async::FramedTcpConnection, Async::HttpServerConnection, and Async::TcpPrioClient< ConT >.

Definition at line 478 of file AsyncTcpConnection.h.

References disconnected.

Referenced by Async::FramedTcpConnection::emitDisconnected(), Async::HttpServerConnection::emitDisconnected(), and onDisconnected().

◆ emitVerifyPeer()

virtual int Async::TcpConnection::emitVerifyPeer	(	int	preverify_ok,
		X509_STORE_CTX *	store_ctx )

inlineprotectedvirtual

Emit the verifyPeer signal.

Parameters

preverify_ok	The basic certificate verifications passed
store_ctx	The OpenSSL X509 store context

Returns: Returns 1 on success or 0 if verification fail

Definition at line 489 of file AsyncTcpConnection.h.

References verifyPeer.

◆ enableSsl()

void Async::TcpConnection::enableSsl ( bool enable )

Enable or disable TLS for this connection.

Parameters

enable Set to true to enable

Examples: AsyncHttpServer_demo.cpp.

◆ freeze()

void Async::TcpConnection::freeze ( void )

Stop all communication.

When a connection is freezed incoming data will be buffered but the dataReceived signal will not be emitted. Written data is also buffered.

◆ isConnected()

bool Async::TcpConnection::isConnected ( void ) const

inline

Check if the connection is established or not.

Returns: Returns true if the connection is established or false if the connection is not established

Definition at line 279 of file AsyncTcpConnection.h.

◆ isIdle()

bool Async::TcpConnection::isIdle ( void ) const

inline

Check if the connection is idle.

Returns: Returns true if the connection is idle

A connection being idle means that it is not connected

Definition at line 287 of file AsyncTcpConnection.h.

◆ isServer()

bool Async::TcpConnection::isServer ( void ) const

inline

Definition at line 328 of file AsyncTcpConnection.h.

◆ localHost()

IpAddress Async::TcpConnection::localHost ( void ) const

Get the local IP address associated with this connection.

Returns: Returns an IP address

◆ localPort()

uint16_t Async::TcpConnection::localPort ( void ) const

Get the local TCP port associated with this connection.

Returns: Returns a port number

◆ onDataReceived()

virtual int Async::TcpConnection::onDataReceived	(	void *	buf,
		int	count )

inlineprotectedvirtual

Called when data has been received on the connection.

Parameters

buf	A buffer containg the read data
count	The number of bytes in the buffer

Returns: Return the number of processed bytes

This function is called when data has been received on this connection. The buffer will contain the bytes read from the operating system. The function will return the number of bytes that has been processed. The bytes not processed will be stored in the receive buffer for this class and presented again to the slot when more data arrives. The new data will be appended to the old data. The default action for this function is to emit the dataReceived signal.

Reimplemented in Async::FramedTcpConnection, and Async::HttpServerConnection.

Definition at line 469 of file AsyncTcpConnection.h.

References dataReceived.

◆ onDisconnected()

virtual void Async::TcpConnection::onDisconnected ( DisconnectReason reason )

inlineprotectedvirtual

Called when a connection has been terminated.

Parameters

reason The reason for the disconnect

This function will be called when the connection has been terminated. The default action for this function is to emit the disconnected signal.

Reimplemented in Async::FramedTcpConnection, Async::HttpServerConnection, and Async::TcpPrioClient< ConT >.

Definition at line 450 of file AsyncTcpConnection.h.

References emitDisconnected().

◆ operator=()

virtual TcpConnection & Async::TcpConnection::operator= ( TcpConnection && other )

virtual

Move assignmnt operator.

Parameters

other The object to move from

Returns: Returns this object

The move operator move the state of a specified TcpConnection object into this object. After the move, the state of the other object will be the same as if it had just been default constructed.

Reimplemented in Async::FramedTcpConnection, and Async::HttpServerConnection.

◆ recvBufLen()

size_t Async::TcpConnection::recvBufLen ( void ) const

inline

Definition at line 229 of file AsyncTcpConnection.h.

◆ remoteHost()

const IpAddress & Async::TcpConnection::remoteHost ( void ) const

inline

Return the IP-address of the remote host.

Returns: Returns the IP-address of the remote host

This function returns the IP-address of the remote host.

Examples: AsyncFramedTcpClient_demo.cpp, AsyncFramedTcpServer_demo.cpp, AsyncHttpServer_demo.cpp, AsyncTcpClient_demo.cpp, AsyncTcpPrioClient_demo.cpp, and AsyncTcpServer_demo.cpp.

Definition at line 266 of file AsyncTcpConnection.h.

Referenced by Async::TcpClientBase::remoteHostName().

◆ remotePort()

uint16_t Async::TcpConnection::remotePort ( void ) const

inline

Return the remote port used.

Returns: Returns the remote port

Examples: AsyncFramedTcpServer_demo.cpp, AsyncHttpServer_demo.cpp, AsyncTcpPrioClient_demo.cpp, and AsyncTcpServer_demo.cpp.

Definition at line 272 of file AsyncTcpConnection.h.

◆ setRecvBufLen()

void Async::TcpConnection::setRecvBufLen ( size_t recv_buf_len )

Set a new receive buffer size.

Parameters

recv_buf_len The new receive buffer size in bytes

This function will resize the receive buffer to the specified size. If the buffer size is reduced and there are more bytes in the current buffer than can be fitted into the new buffer, the buffer resize request vill be silently ignored.

◆ setRemoteAddr()

void Async::TcpConnection::setRemoteAddr ( const IpAddress & remote_addr )

protected

Setup information about the connection.

Parameters

remote_addr The remote IP-address of the connection

Use this function to set up the remote IP-address for the connection.

◆ setRemotePort()

void Async::TcpConnection::setRemotePort ( uint16_t remote_port )

protected

Setup information about the connection.

Parameters

remote_port The remote TCP-port of the connection

Use this function to set up the remote port for the connection.

◆ setSocket()

void Async::TcpConnection::setSocket ( int sock )

protected

Setup information about the connection.

Parameters

sock	The socket for the connection to handle

Use this function to set up the socket for the connection.

◆ setSslContext()

void Async::TcpConnection::setSslContext	(	SslContext &	ctx,
		bool	is_server )

Set the OpenSSL context to use when setting up the connection.

Parameters

ctx	The context object to use
is_server	Set to true if this is a server side connection

This function should be called prior to calling enableSsl in order to set up a TLS context to use when setting up the connection.

◆ socket()

int Async::TcpConnection::socket ( void ) const

inlineprotected

Return the socket file descriptor.

Returns: Returns the currently used socket file descriptor

Use this function to get the socket file descriptor that is currently in use. If it is -1 it has not been set.

Definition at line 433 of file AsyncTcpConnection.h.

◆ sslCertificate()

Async::SslX509 Async::TcpConnection::sslCertificate ( void ) const

◆ sslContext()

SslContext * Async::TcpConnection::sslContext ( void )

inline

Definition at line 326 of file AsyncTcpConnection.h.

◆ sslPeerCertificate()

SslX509 Async::TcpConnection::sslPeerCertificate ( void )

Get the peer certificate associated with this connection.

Returns: Returns the X509 certificate associated with the peer

This function is used to retrieve the peer certificate that the peer has sent to us during the setup phase. If no certificate was sent this function will return a null object so checking for that condition can be done by comparing the returned object with nullptr.

◆ sslVerifyResult()

long Async::TcpConnection::sslVerifyResult ( void ) const

Get the result of the certificate verification process.

Returns: Returns the verification result (e.g. X509_V_OK for ok)

◆ unfreeze()

void Async::TcpConnection::unfreeze ( void )

Reenable all communication.

When a frozen connection is unfreezed the dataReceived signal will be emitted for any received and buffered data. If there are any written data that has been buffered it will be transmitted.

◆ write()

virtual int Async::TcpConnection::write	(	const void *	buf,
		int	count )

virtual

Write data to the TCP connection.

Parameters

buf	The buffer containing the data to send
count	The number of bytes to send from the buffer

Returns: Returns the number of bytes written or -1 on failure

Reimplemented in Async::FramedTcpConnection.

Examples: AsyncFramedTcpClient_demo.cpp, AsyncTcpClient_demo.cpp, and AsyncTcpServer_demo.cpp.

Friends And Related Symbol Documentation

◆ TcpClientBase

friend class TcpClientBase

friend

Definition at line 499 of file AsyncTcpConnection.h.

Member Data Documentation

◆ dataReceived

sigc::signal<int, TcpConnection *, void *, int> Async::TcpConnection::dataReceived

A signal that is emitted when data has been received on the connection.

Parameters

buf	A buffer containg the read data
count	The number of bytes in the buffer

Returns: Return the number of processed bytes

This signal is emitted when data has been received on this connection. The buffer will contain the bytes read from the operating system. The slot must return the number of bytes that has been processed. The bytes not processed will be stored in the receive buffer for this class and presented again to the slot when more data arrives. The new data will be appended to the old data.

Examples: AsyncTcpServer_demo.cpp.

Definition at line 374 of file AsyncTcpConnection.h.

Referenced by onDataReceived().

◆ DEFAULT_RECV_BUF_LEN

const int Async::TcpConnection::DEFAULT_RECV_BUF_LEN = 1024

static

The default size of the reception buffer.

Definition at line 178 of file AsyncTcpConnection.h.

◆ disconnected

sigc::signal<void, TcpConnection *, DisconnectReason> Async::TcpConnection::disconnected

Get common name for the SSL connection.

Returns: Returns the common name for the associated X509 certificate

A signal that is emitted when a connection has been terminated

Parameters

con	The connection object
reason	The reason for the disconnect

Definition at line 358 of file AsyncTcpConnection.h.

Referenced by emitDisconnected().

◆ sslConnectionReady

sigc::signal<void, TcpConnection*> Async::TcpConnection::sslConnectionReady

A signal that is emitted when the SSL connection is ready.

Parameters

con	The connection object

This signal is emitted when the SSL initialization and handshake has finished after the application has called the enableSsl() function.

Definition at line 399 of file AsyncTcpConnection.h.

◆ verifyPeer

sigc::signal<if_all_true_acc::result_type, TcpConnection*, int, X509_STORE_CTX*>::accumulated<if_all_true_acc> Async::TcpConnection::verifyPeer

A signal that is emitted on SSL/TLS certificate verification.

Parameters

con	The connection object
preverify_ok	Is true if the OpenSSL verification is ok
x509_store_ctx	The X509 store context

Connect to this signal to be able to tap in to the certificate verification process. All slots that connect to this signal must return true for the verification process to succeed.

For more information on the function arguments have a look at the manual page for the OpenSSL function SSL_set_verify().

Definition at line 390 of file AsyncTcpConnection.h.

Referenced by emitVerifyPeer().

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

AsyncTcpConnection.h

Classes

Public Types

Public Member Functions

Static Public Member Functions

Public Attributes

Static Public Attributes

Protected Member Functions

Friends

Detailed Description

Member Enumeration Documentation

◆ DisconnectReason

Constructor & Destructor Documentation

◆ TcpConnection() [1/2]

◆ TcpConnection() [2/2]

◆ ~TcpConnection()

Member Function Documentation

◆ closeConnection()

◆ disconnect()

◆ disconnectReasonStr()

◆ emitDisconnected()

◆ emitVerifyPeer()

◆ enableSsl()

◆ freeze()

◆ isConnected()

◆ isIdle()

◆ isServer()

◆ localHost()

◆ localPort()

◆ onDataReceived()

◆ onDisconnected()

◆ operator=()

◆ recvBufLen()

◆ remoteHost()

◆ remotePort()

◆ setRecvBufLen()

◆ setRemoteAddr()

◆ setRemotePort()

◆ setSocket()

◆ setSslContext()

◆ socket()

◆ sslCertificate()

◆ sslContext()

◆ sslPeerCertificate()

◆ sslVerifyResult()

◆ unfreeze()

◆ write()

Friends And Related Symbol Documentation

◆ TcpClientBase

Member Data Documentation

◆ dataReceived

◆ DEFAULT_RECV_BUF_LEN

◆ disconnected

◆ sslConnectionReady

◆ verifyPeer