Interface to realizes ethernet based communications. More...

#include <Socket.hpp>

Public Types
typedef std::shared_ptr< Socket >	Ptr
	Contextual definition of pointer type.

Public Member Functions
	Socket (SocketType type, SocketDomain domain, SocketBlockingMode blockingMode)
	Constructs an Socket instance. More...

	Socket (const Socket &arg)=delete
	Copy contructor.

Socket &	operator= (const Socket &arg)=delete
	Assignment operator.

	~Socket (void)
	Destructs this instance and frees all resouces. More...

SocketType	GetSocketType (void) const
	Returns the type of the socket. More...

SocketDomain	GetSocketDomain (void) const
	Returns the utilized domain. More...

bool	IsBlocking (void) const
	Checks if the socket is in blocking mode. More...

bool	IsConnected (void) const
	Checks if this socket is connected with a remote peer. More...

IpAddress	GetRemoteIpAddress (void) const
	If this socket is connected this method returns the ip-address (v4). More...

int	GetRemotePort (void) const
	If this socket is connected this method returns the port of the connection. More...

Ptr	Accept (IpAddress &ip4address, int &port, SocketError &error)
	Accepts a pending connection request. More...

SocketError	Bind (const IpAddress &ip4Address, int port)
	Binds the socket to a specific address and port combination. More...

SocketError	Bind2 (const IpAddress &ip4Address, int &port)
	Binds the socket to a specific address and port combination. More...

SocketError	Connect (const IpAddress &ip4Address, int port)
	Tries to connect with a remote socket. More...

SocketError	Listen (size_t backlog)
	Marks this socket as a passive socket that accepts incoming connection requests. More...

SocketError	Shutdown (void)
	Shuts down a full-duplex connection. More...

SocketError	Shutdown (ShutdownMode mode)
	Shuts down a full-duplex connection. More...

SocketError	Close (void)
	Closes the socket. This ends all communication on the socket. More...

int	Send (const void *pBuffer, size_t length, SocketError &error)
	Transmit data over the socket that is in a connected state. More...

int	SendTo (const void *pBuffer, size_t length, IpAddress ip4Adress, int port, SocketError &error)
	Like Send but this method is to be used on sockets created with SocketType::Udp. More...

int	Receive (void *pBuffer, size_t length, SocketError &error)
	Reads data from connected socket. More...

int	ReceiveFrom (void *pBuffer, size_t length, IpAddress &ip4Adress, int &port, SocketError &error)
	Like Receive but this method is to be used on sockets created with SocketType::Udp. More...

bool	Select (SelectMode mode, Microseconds timeout, SocketError &error)
	Checks if an i/o operation can be performed without blocking the calling thread. More...

int	Poll (PollMode mode, Milliseconds timeout, SocketError &error)
	Checks if an i/o operation can be processed without blocking. More...

SocketError	SetSocketOption (SocketOptionName optionName, const void *optionValue, size_t optionLength)
	Sets a single option on the socket. More...

SocketError	GetSocketOption (SocketOptionName optionName, void optionValue, size_t optionLength) const
	Returns current value of queried socket option. More...

SocketError	SetOptionReuseAddress (bool enabled)
	Enables/Disables the reuse-address option for this socket. More...

SocketError	GetOptionReuseAddress (bool &enabled) const
	Checks if reuse-address is enabled. More...

SocketError	SetOptionKeepAlive (bool enabled)
	Enables/Disables the keep-alive option for this socket. More...

SocketError	GetOptionKeepAlive (bool &enabled) const
	Checks if keep-alive is enabled. More...

SocketError	SetOptionBroadcast (bool enabled)
	Enables/Disables broadcast for this socket. More...

SocketError	GetOptionBroadcast (bool &enabled) const
	Checks if broadcast is enabled. More...

SocketError	SetOptionNoDelay (bool enabled)
	Enables/Disables no-delay for this socket. More...

SocketError	GetOptionNoDelay (bool &enabled) const
	Checks if no-delay is enabled. More...

SocketError	SetOptionBlocking (bool enable)
	Enables/disables the blocking mode of this socket.. More...

SocketError	SetOptionLinger (bool enable, size_t timeout)
	Sets the amount of time a socket resides in TIME_WAIT state after active close. More...

SocketError	GetOptionLinger (bool &enable, size_t &timeout)
	Returns the current linger options. For more information see Arp::System::Commons::Net::Socket::SetOptionLinger More...

Friends
class	TlsSocket

class	TlsSocket2

Detailed Description

Interface to realizes ethernet based communications.

Instances of this class can be used to realize an ethernet based communication with remote peers. By now 2 different types of protocols are supported. Either UPD or TCP. A simple TCP echo server can be realized with the following code.

class TcpEchoServer
{
public:
 
    TcpEchoServer(void);
 
    void Process();
 
private:
 
    Socket listeningSocket;
};
 
inline TcpEchoServer::TcpEchoServer(void) : listeningSocket(SocketType::Tcp, SocketDomain::Ipv4, SocketBlockingMode::Blocking)
{}
 
void TcpEchoServer::Process()
{
    int port = 45451;
    // Bind the port to any local address.
    if (listeningSocket.Bind(0, port) != SocketError::None)
    {
        return;
    }
 
    // Make socket a passive listener that processes incoming connection requests.
    if (listeningSocket.Listen(10) != SocketError::None)
    {
        return;
    }
 
    uint32 remoteIp;
    int remotePort;
    SocketError error;
    // Wait for the first client that requests a connection and accept it.
    Socket::Ptr newSocket = listeningSocket.Accept(remoteIp, remotePort, error);
    if (newSocket != nullptr)
    {
        byte buffer[256];
        // No receive any message and reply it directly to the sender.
        while (true)
        {
            memset(buffer, 0, sizeof(buffer));
            int bytesReceived = newSocket->Receive(buffer, sizeof(buffer), error);
            int sendResult = newSocket->Send(buffer, bytesReceived, error);
        }
        (void) newSocket->Shutdown();
        (void) newSocket->Close();
    }
}

The server uses a single passive socket called listenigSocket that is used to wait for a single connection. Therefore the socket is created during instance creation of the TcpEchoServer-object as a blocking TCP socket that uses Ipv4 protocol. In the Process method the socket is then bound to all local network interfaces and port 45451. Note that from this time on, no other socket can be bound to any address and port 45451 since the socket has enable reusing of addresses. See Arp::System::Commons::Net::Socket::SetOptionReuseAddress for more information. Afterwards the socket is marked as passive socket listening for incoming connection request by invoking Arp::System::Commons::Net::Socket::Listen. Since the socket is a blocking socket the server will block at the accept call until a connection request reaches the socket. Afterwards it justs reads any data of up to 256 bytes and simply returns them to the sender.

A client on the same machine can then connect and communicate with the server using the following code

Socket socket(SocketType::Tcp, SocketDomain::Ipv4, SocketBlockingMode::Blocking);
int32 address = 127 + (0 << 8) + (0 << 16) + (1 << 24);
SocketError error = socket.Connect(address, 45451);
if (error == SocketError::None)
{
    char *pMessage = "test-message";
    int bytes = socket.Send(pMessage, strlen(pMessage), error);
 
    char message[256];
    bytes = socket.Receive(message, sizeof(message), error);
}

Constructor & Destructor Documentation

◆ Socket()

Arp::System::Commons::Net::Socket::Socket	(	SocketType	type,
		SocketDomain	domain,
		SocketBlockingMode	blockingMode
	)

Constructs an Socket instance.

Parameters

type	The type of socket to be created.
domain	The address domain for the socket. Currently only SocketDomain::Ipv4 is supported.
blockingMode	The blocking mode of the socket.

◆ ~Socket()

Arp::System::Commons::Net::Socket::~Socket ( void )

Destructs this instance and frees all resouces.

This will also close the socket if it is not yet closed.

Member Function Documentation

◆ Accept()

Ptr Arp::System::Commons::Net::Socket::Accept	(	IpAddress &	ip4address,
		int &	port,
		SocketError &	error
	)

Accepts a pending connection request.

Before a socket can accept connection requests, it must be Bind with an address and must be set to Listen state.

If no connection request is pending and the socket is in

blocking mode, the call blocks until a remote peer sends a connection request
non-blocking mode, the call returns a nullptr and error is set to SocketError::WouldBlock

Currently only ip v4 addresses are supported. The address must be encoded in a single 32 bit value. For an example how to encode the address see the example in the class description.

Parameters

ip4address	holds the 32 bit encoded ip v4 address of the connected peer socket.
port	Holds the port number of the connected peer socket.
error	Holds error code in case the method returns nullptr.

Returns: Pointer to class instance representing accepted socket, nullptr otherwise.

◆ Bind()

SocketError Arp::System::Commons::Net::Socket::Bind	(	const IpAddress &	ip4Address,
		int	port
	)

Binds the socket to a specific address and port combination.

Currently only ip v4 addresses are supported. The address must be encoded in a single 32 bit value. For an example how to encode the address see the example in the class description.

To bind this socket to all local interfaces, 0 has to be assigned to parameter ip4Address.

Parameters

ip4Address	IP v4 based address to connect to.
port	Port number to connect with.

Returns: See SocketError for more information on possible return values.

◆ Bind2()

SocketError Arp::System::Commons::Net::Socket::Bind2	(	const IpAddress &	ip4Address,
		int &	port
	)

Binds the socket to a specific address and port combination.

bind2 returns the actual port used by this socket in the port parameter in contrast to bind i.e. use bind(ip, 0) to let the os choose the port to use, after the call port will contain the port choosed by the os.

Currently only ip v4 addresses are supported. The address must be encoded in a single 32 bit value. For an example how to encode the address see the example in the class description.

To bind this socket to all local interfaces, 0 has to be assigned to parameter ip4Address.

Parameters

ip4Address	IP v4 based address to connect to.
port	Port number to connect with.

Returns: See SocketError for more information on possible return values.

◆ Close()

SocketError Arp::System::Commons::Net::Socket::Close ( void )

Closes the socket. This ends all communication on the socket.

After Close() no further calls (i.e. a new connect()) on this socket are possible thus the socket instance must be destroyed.

Returns: See SocketError for more information on possible return values.

◆ Connect()

SocketError Arp::System::Commons::Net::Socket::Connect	(	const IpAddress &	ip4Address,
		int	port
	)

Tries to connect with a remote socket.

Currently only ip v4 addresses are supported. The address must be encoded in a single 32 bit value. For an example how to encode the address see the example in the class description.

Parameters

ip4Address	IP v4 based address to connect to.
port	Port number to connect with.

Returns: See SocketError for more information on possible return values.

◆ GetOptionBroadcast()

SocketError Arp::System::Commons::Net::Socket::GetOptionBroadcast ( bool & enabled ) const

Checks if broadcast is enabled.

See SetOptionBroadcast for more information.

Parameters

enabled Container for current option state.

Returns: See SocketError for more information on possible return values.

◆ GetOptionKeepAlive()

SocketError Arp::System::Commons::Net::Socket::GetOptionKeepAlive ( bool & enabled ) const

Checks if keep-alive is enabled.

See SetOptionKeepAlive for more information.

Parameters

enabled Container for current option state.

Returns: See SocketError for more information on possible return values.

◆ GetOptionLinger()

SocketError Arp::System::Commons::Net::Socket::GetOptionLinger	(	bool &	enable,
		size_t &	timeout
	)

Returns the current linger options. For more information see Arp::System::Commons::Net::Socket::SetOptionLinger

Parameters

enable	True if linger option is active, otherwise false.
timeout	Holds current timeout value in seconds if linger is activated on this socket.

Returns: See SocketError for more information on possible return values.

◆ GetOptionNoDelay()

SocketError Arp::System::Commons::Net::Socket::GetOptionNoDelay ( bool & enabled ) const

Checks if no-delay is enabled.

See SetOptionNoDelay for more information.

Parameters

enabled Container for current option state.

Returns: See SocketError for more information on possible return values.

◆ GetOptionReuseAddress()

SocketError Arp::System::Commons::Net::Socket::GetOptionReuseAddress ( bool & enabled ) const

Checks if reuse-address is enabled.

See SetOptionReuseAddress for more information

Parameters

enabled Container for current option state.

Returns: See SocketError for more information on possible return values.

◆ GetRemoteIpAddress()

IpAddress Arp::System::Commons::Net::Socket::GetRemoteIpAddress ( void ) const

inline

If this socket is connected this method returns the ip-address (v4).

This returned address is encoded in network byte order.

Returns: The ip-address (v4) of the remote peer if this socket is connected, otherwise 0 is returned.

◆ GetRemotePort()

int Arp::System::Commons::Net::Socket::GetRemotePort ( void ) const

inline

If this socket is connected this method returns the port of the connection.

The port number is returned in host byte order, not in network byte order.

Returns: The port of the connection if this port is connected, otherwise 0 is returned.

◆ GetSocketDomain()

SocketDomain Arp::System::Commons::Net::Socket::GetSocketDomain ( void ) const

inline

Returns the utilized domain.

Returns: The utilized domain.

◆ GetSocketOption()

SocketError Arp::System::Commons::Net::Socket::GetSocketOption	(	SocketOptionName	optionName,
		void *	optionValue,
		size_t *	optionLength
	)		const

Returns current value of queried socket option.

Parameters

optionName	Name of option where current value is queried.
optionValue	Pointer to buffer where current socket option value is to be stored.
optionLength	Value-Result argument. Must be initialized to byte size of buffer pointed to by optionValue. Holds amount of bytes set in buffer optionValue after call returned.

Returns: See SocketError for more information on possible return values.

◆ GetSocketType()

SocketType Arp::System::Commons::Net::Socket::GetSocketType ( void ) const

inline

Returns the type of the socket.

Returns: Type of socket.

◆ IsBlocking()

bool Arp::System::Commons::Net::Socket::IsBlocking ( void ) const

inline

Checks if the socket is in blocking mode.

Returns: True if socket is in blocking mode, otherwise false is returned.

◆ IsConnected()

bool Arp::System::Commons::Net::Socket::IsConnected ( void ) const

inline

Checks if this socket is connected with a remote peer.

Returns: True if this socket is connected, otherwise false is returned.

◆ Listen()

SocketError Arp::System::Commons::Net::Socket::Listen ( size_t backlog )

Marks this socket as a passive socket that accepts incoming connection requests.

A socket in listening state features an internal queue where incoming connection requests are stored until they are processed by an Accept invocation. The maximal capacity of this queue is determined by the parameter backlog. If a connection request arrives while the queue is filled, the client may receive an error telling that the connection is refused or, if the utilized protocol allows retransmissions, the request may be ignored so that a consecutive reattempt to connnect may succeed.

Parameters

backlog Defines the maximum number of pending connection requests.

Returns: See SocketError for more information on possible return values.

◆ Poll()

int Arp::System::Commons::Net::Socket::Poll	(	PollMode	mode,
		Milliseconds	timeout,
		SocketError &	error
	)

Checks if an i/o operation can be processed without blocking.

Parameters

mode	Specifies the i/o operation to be checked.
timeout	Specifies the timeout to wait for the socket to get ready for the i/o operation. If set to zero, the call will return immediately. `Milliseconds(-1)` determines infinite.
error	The resulting socket error, if any error occur.

Returns: 1 if the specified i/o operation might be processed without blocking. The error is <cref name="SocketError::ConnectionReset" >, if the socket was closed local or remote. 0 if this operation timed out. -1 if any error occurs. Check the error to get more infos about the error.

◆ Receive()

int Arp::System::Commons::Net::Socket::Receive	(	void *	pBuffer,
		size_t	length,
		SocketError &	error
	)

Reads data from connected socket.

Parameters

pBuffer	Pointer to buffer where read data can be stored.
length	Capacity in bytes of buffer pBuffer.
error	Container variable holding error code after call returned.

Returns: Amount of bytes read from socket, -1 in case of failure.

◆ ReceiveFrom()

int Arp::System::Commons::Net::Socket::ReceiveFrom	(	void *	pBuffer,
		size_t	length,
		IpAddress &	ip4Adress,
		int &	port,
		SocketError &	error
	)

Like Receive but this method is to be used on sockets created with SocketType::Udp.

Parameters

pBuffer	Pointer to buffer where read data can be stored.
length	Capacity in bytes of buffer pBuffer.
ip4Adress	Source address (ip v4 only) of received data.
port	Source port number of received data.
error	Container variable holding error code after call returned.

Returns: Amount of bytes read from socket, -1 in case of failure.

◆ Select()

bool Arp::System::Commons::Net::Socket::Select	(	SelectMode	mode,
		Microseconds	timeout,
		SocketError &	error
	)

Checks if an i/o operation can be performed without blocking the calling thread.

Parameters

mode	Determines the i/o operation to be checked.
timeout	Specifies the time to wait for the socket to be ready for the i/o operation. If set to zero, the call will return immediately.
error	Container variable holding error code after call returned.

Returns: true if the specified i/o operation can be performed without blocking, otherwise false is returned. true is also returned, when the socket was closed local or remote (Linux socket API behaviour!). The only way to determine if the socket is still alive, is through a subsequent call of <cref name="Socket::Receive">.

This operation is a legacy operation, use <cref name="Socket::Poll"> instead.

◆ Send()

int Arp::System::Commons::Net::Socket::Send	(	const void *	pBuffer,
		size_t	length,
		SocketError &	error
	)

Transmit data over the socket that is in a connected state.

Parameters

pBuffer	Pointer to buffer containing serialized data to be send.
length	Amount of bytes to be send.
error	Container variable holding error code after call returned.

Returns: Amount of transmitted bytes, -1 in case of failure.

◆ SendTo()

int Arp::System::Commons::Net::Socket::SendTo	(	const void *	pBuffer,
		size_t	length,
		IpAddress	ip4Adress,
		int	port,
		SocketError &	error
	)

Like Send but this method is to be used on sockets created with SocketType::Udp.

Parameters

pBuffer	Pointer to buffer containing serialized data to be send.
length	Amount of bytes to be send.
ip4Adress	Destination address (ip v4 only) for data.
port	Destination port number for data.
error	Container variable holding error code after call returned.

Returns: Amount of transmitted bytes, -1 in case of failure.

◆ SetOptionBlocking()

SocketError Arp::System::Commons::Net::Socket::SetOptionBlocking ( bool enable )

Enables/disables the blocking mode of this socket..

Parameters

enable true if the blocking mode shall be enabled, otherwise false.

Returns: SocketError for more information on possible return values.

◆ SetOptionBroadcast()

SocketError Arp::System::Commons::Net::Socket::SetOptionBroadcast ( bool enabled )

Enables/Disables broadcast for this socket.

This option is only valid for datagram sockets and can be used to enable the sending of packets to broadcast addresses.

Parameters

enabled Set to tro true activate option, otherwise set to false.

Returns: See SocketError for more information on possible return values.

◆ SetOptionKeepAlive()

SocketError Arp::System::Commons::Net::Socket::SetOptionKeepAlive ( bool enabled )

Enables/Disables the keep-alive option for this socket.

Enables the sending of keep-alive probes to remote peers to check if a connection is still up if no data was transmitted for a while.

This option is only valid for connection-based sockets.

Parameters

enabled Set to true to activate option, otherwise set to false.

Returns: See SocketError for more information on possible return values.

◆ SetOptionLinger()

SocketError Arp::System::Commons::Net::Socket::SetOptionLinger	(	bool	enable,
		size_t	timeout
	)

Sets the amount of time a socket resides in TIME_WAIT state after active close.

The port of a connection that is activly closed, i.e. first calls Arp::System::Commons::Net::Socket::Close will reside in a state called TIME_WAIT for a specific amount of time. This prevents subsequently delivered packages to be considered to belong to a potential new established connection using the same port.

The time a port is in TIME_WAIT state can be adjusted using this method. A smaller timeout can be of interest if the system has to manage a lot of connections that only are active for a small amount of time. In this case a small timeout will prevent a lot of socket residing in TIME_WAIT and are therefore unavailable for creation of new connections.

Parameters

enable	Set to true to activate new linger timeout, false otherwise.
timeout	The new linger timeout in seconds.

Returns: See SocketError for more information on possible return values.

◆ SetOptionNoDelay()

SocketError Arp::System::Commons::Net::Socket::SetOptionNoDelay ( bool enabled )

Enables/Disables no-delay for this socket.

If this option is enabled packets are not buffered by the TCP stack stack to optimize the network usage by only sending sufficiently large amount of data. Instead even small packets are send immediately over the network.

Parameters

enabled Set to tro true activate option, otherwise set to false.

Returns: See SocketError for more information on possible return values.

◆ SetOptionReuseAddress()

SocketError Arp::System::Commons::Net::Socket::SetOptionReuseAddress ( bool enabled )

Enables/Disables the reuse-address option for this socket.

Activating this option changes the validation process for socket bindings. If the option is disabled and one port is for example bound to 0.0.0.0:21 (any local address and port 21) another port can not be bound to 192.168.0.4:21 because the wildcard IP address 0.0.0.0 conflicts with the other address. If the option is enabled, bounding the second socket will succeed.

Parameters

enabled Set to true to enable the option, otherwise set to false.

Returns: See SocketError for more information on possible return values.

◆ SetSocketOption()

SocketError Arp::System::Commons::Net::Socket::SetSocketOption	(	SocketOptionName	optionName,
		const void *	optionValue,
		size_t	optionLength
	)

Sets a single option on the socket.

Parameters

optionName	Name of option ot be set.
optionValue	Pointer to additional data for socket option.
optionLength	Byte size of buffer pointed to by optionValue.

Returns: See SocketError for more information on possible return values.

◆ Shutdown() [1/2]

SocketError Arp::System::Commons::Net::Socket::Shutdown ( ShutdownMode mode )

Shuts down a full-duplex connection.

After the shutdown has been called, further reception and transmission on the socket is disallowed.

Parameters

mode	Specifies if read or write operations should be shutdown.

Returns: See SocketError for more information on possible return values.

◆ Shutdown() [2/2]

SocketError Arp::System::Commons::Net::Socket::Shutdown ( void )

Shuts down a full-duplex connection.

After the shutdown has been called, further reception and transmission on the socket is disallowed.

Returns: See SocketError for more information on possible return values.

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

Arp/System/Commons/Net/Socket.hpp

Public Types

Public Member Functions

Friends

Detailed Description

Constructor & Destructor Documentation

◆ Socket()

◆ ~Socket()

Member Function Documentation

◆ Accept()

◆ Bind()

◆ Bind2()

◆ Close()

◆ Connect()

◆ GetOptionBroadcast()

◆ GetOptionKeepAlive()

◆ GetOptionLinger()

◆ GetOptionNoDelay()

◆ GetOptionReuseAddress()

◆ GetRemoteIpAddress()

◆ GetRemotePort()

◆ GetSocketDomain()

◆ GetSocketOption()

◆ GetSocketType()

◆ IsBlocking()

◆ IsConnected()

◆ Listen()

◆ Poll()

◆ Receive()

◆ ReceiveFrom()

◆ Select()

◆ Send()

◆ SendTo()

◆ SetOptionBlocking()

◆ SetOptionBroadcast()

◆ SetOptionKeepAlive()

◆ SetOptionLinger()

◆ SetOptionNoDelay()

◆ SetOptionReuseAddress()

◆ SetSocketOption()

◆ Shutdown() [1/2]

◆ Shutdown() [2/2]