GNU CommonC++
Public Member Functions | Protected Attributes

ost::UDPSocket Class Reference

UDP sockets implement the TCP SOCK_DGRAM UDP protocol. More...

#include <socket.h>

Inheritance diagram for ost::UDPSocket:
ost::Socket ost::UDPBroadcast ost::UDPReceive ost::UDPTransmit ost::UDPDuplex ost::UDPDuplex

List of all members.

Public Member Functions

 UDPSocket (Family family=IPV4)
 Create an unbound UDP socket, mostly for internal use.
 UDPSocket (const char *name, Family family=IPV4)
 Create a UDP socket bound by a service name.
 UDPSocket (const IPV4Address &bind, tpport_t port)
 Create a UDP socket and bind it to a specific interface and port address so that other UDP sockets on remote machines (or the same host) may find and send UDP messages to it.
 UDPSocket (const IPV6Address &bind, tpport_t port)
virtual ~UDPSocket ()
 Destroy a UDP socket as a socket.
Error setLoopback (bool enable)
 Set the loopback.
Error setMulticast (bool enable)
 Set the multicast.
Error setTimeToLive (char ttl)
 Set time to live.
void setPeer (const IPV4Host &host, tpport_t port)
 set the peer address to send message packets to.
void connect (const IPV4Host &host, tpport_t port)
void setPeer (const IPV6Host &host, tpport_t port)
void connect (const IPV6Host &host, tpport_t port)
Socket::Error getInterfaceIndex (const char *ethX, int &InterfaceIndex)
 get the interface index for a named network device
Socket::Error join (const IPV4Multicast &ia, int InterfaceIndex)
 join a multicast group on a particular interface
ssize_t send (const void *buf, size_t len)
 Send a message packet to a peer host.
ssize_t receive (void *buf, size_t len, bool reply=false)
 Receive a message from any host.
IPV4Host getIPV4Peer (tpport_t *port=NULL) const
 Examine address of sender of next waiting packet.
IPV4Host getPeer (tpport_t *port=NULL) const
IPV6Host getIPV6Peer (tpport_t *port=NULL) const
ssize_t peek (void *buf, size_t len)
 Examine contents of next waiting packet.
void setPeer (const char *service)
 Associate socket with a named connection.
void connect (const char *service)
Error disconnect (void)
 Disassociate this socket from any host connection.

Protected Attributes

union {
   struct sockaddr_in6   ipv6
   struct sockaddr_in   ipv4
peer
Family family

Detailed Description

UDP sockets implement the TCP SOCK_DGRAM UDP protocol.

They can be used to pass unverified messages between hosts, or to broadcast a specific message to an entire subnet. Please note that Streaming of realtime data commonly use UDPDuplex related classes rather than UDPSocket.

In addition to connected TCP sessions, Common C++ supports UDP sockets and these also cover a range of functionality. Like a TCPSocket, A UDPSocket can be created bound to a specific network interface and/or port address, though this is not required. UDP sockets also are usually either connected or otherwise "associated" with a specific "peer" UDP socket. Since UDP sockets operate through discreet packets, there are no streaming operators used with UDP sockets.

In addition to the UDP "socket" class, there is a "UDPBroadcast" class. The UDPBroadcast is a socket that is set to send messages to a subnet as a whole rather than to an individual peer socket that it may be associated with.

UDP sockets are often used for building "realtime" media streaming protocols and full duplex messaging services. When used in this manner, typically a pair of UDP sockets are used together; one socket is used to send and the other to receive data with an associated pair of UDP sockets on a "peer" host. This concept is represented through the Common C++ UDPDuplex object, which is a pair of sockets that communicate with another UDPDuplex pair.

Author:
David Sugar <dyfet@ostel.com> Unreliable Datagram Protocol sockets.

Constructor & Destructor Documentation

ost::UDPSocket::UDPSocket ( Family  family = IPV4)

Create an unbound UDP socket, mostly for internal use.

ost::UDPSocket::UDPSocket ( const char *  name,
Family  family = IPV4 
)

Create a UDP socket bound by a service name.

ost::UDPSocket::UDPSocket ( const IPV4Address bind,
tpport_t  port 
)

Create a UDP socket and bind it to a specific interface and port address so that other UDP sockets on remote machines (or the same host) may find and send UDP messages to it.

On failure to bind, an exception is thrown.

Parameters:
bindaddress to bind this socket to.
portnumber to bind this socket to.
ost::UDPSocket::UDPSocket ( const IPV6Address bind,
tpport_t  port 
)
virtual ost::UDPSocket::~UDPSocket ( ) [virtual]

Destroy a UDP socket as a socket.


Member Function Documentation

void ost::UDPSocket::connect ( const IPV4Host host,
tpport_t  port 
)
void ost::UDPSocket::connect ( const char *  service)
void ost::UDPSocket::connect ( const IPV6Host host,
tpport_t  port 
)

Reimplemented in ost::UDPReceive, and ost::UDPDuplex.

Error ost::UDPSocket::disconnect ( void  )

Disassociate this socket from any host connection.

No data should be read or written until a connection is established.

Reimplemented in ost::UDPDuplex.

Socket::Error ost::UDPSocket::getInterfaceIndex ( const char *  ethX,
int &  InterfaceIndex 
)

get the interface index for a named network device

Parameters:
ethXis device name, like "eth0" or "eth1"
InterfaceIndexis the index value returned by os
IPV4Host ost::UDPSocket::getIPV4Peer ( tpport_t port = NULL) const

Examine address of sender of next waiting packet.

This also sets "peer" address to the sender so that the next "send" message acts as a "reply". This additional behavior overides the standard socket getSender behavior.

Parameters:
portpointer to hold port number.

Reimplemented from ost::Socket.

IPV6Host ost::UDPSocket::getIPV6Peer ( tpport_t port = NULL) const

Reimplemented from ost::Socket.

IPV4Host ost::UDPSocket::getPeer ( tpport_t port = NULL) const [inline]

Reimplemented from ost::Socket.

Socket::Error ost::UDPSocket::join ( const IPV4Multicast ia,
int  InterfaceIndex 
)

join a multicast group on a particular interface

Parameters:
iais the multicast address to use
InterfaceIndexis the index value returned by getInterfaceIndex
ssize_t ost::UDPSocket::peek ( void *  buf,
size_t  len 
) [inline]

Examine contents of next waiting packet.

Parameters:
bufpointer to packet buffer for contents.
lenof packet buffer.
Returns:
number of bytes examined.

References _IOLEN64.

ssize_t ost::UDPSocket::receive ( void *  buf,
size_t  len,
bool  reply = false 
)

Receive a message from any host.

Parameters:
bufpointer to packet buffer to receive.
lenof packet buffer to receive.
replysave sender address for reply if true.
Returns:
number of bytes received.
ssize_t ost::UDPSocket::send ( const void *  buf,
size_t  len 
)

Send a message packet to a peer host.

Parameters:
bufpointer to packet buffer to send.
lenof packet buffer to send.
Returns:
number of bytes sent.

Reimplemented in ost::UDPTransmit.

Error ost::UDPSocket::setLoopback ( bool  enable) [inline]

Set the loopback.

References ost::Socket::setLoopbackByFamily().

Error ost::UDPSocket::setMulticast ( bool  enable) [inline]

Set the multicast.

Reimplemented in ost::UDPTransmit, and ost::UDPReceive.

References ost::Socket::setMulticastByFamily().

void ost::UDPSocket::setPeer ( const IPV6Host host,
tpport_t  port 
)
void ost::UDPSocket::setPeer ( const char *  service)

Associate socket with a named connection.

void ost::UDPSocket::setPeer ( const IPV4Host host,
tpport_t  port 
)

set the peer address to send message packets to.

This can be set before every send() call if nessisary.

Parameters:
hostaddress to send packets to.
portnumber to deliver packets to.
Error ost::UDPSocket::setTimeToLive ( char  ttl) [inline]

Set time to live.

References ost::Socket::setTimeToLiveByFamily().


Member Data Documentation

struct sockaddr_in ost::UDPSocket::ipv4
struct sockaddr_in6 ost::UDPSocket::ipv6
union { ... } ost::UDPSocket::peer [protected]

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