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ost::Socket Class Reference

The Socket is used as the base for all Internet protocol services under Common C++. More...

#include <socket.h>

Inheritance diagram for ost::Socket:
ost::DCCPSocket ost::SimpleTCPStream ost::SocketPort ost::TCPSocket ost::TCPStream ost::TCPV6Socket ost::UDPSocket ost::UnixSocket ost::UnixStream

List of all members.

Public Types

enum  Family { IPV6 = AF_INET6, IPV4 = AF_INET }
enum  Error {
  errSuccess = 0, errCreateFailed, errCopyFailed, errInput,
  errInputInterrupt, errResourceFailure, errOutput, errOutputInterrupt,
  errNotConnected, errConnectRefused, errConnectRejected, errConnectTimeout,
  errConnectFailed, errConnectInvalid, errConnectBusy, errConnectNoRoute,
  errBindingFailed, errBroadcastDenied, errRoutingDenied, errKeepaliveDenied,
  errServiceDenied, errServiceUnavailable, errMulticastDisabled, errTimeout,
  errNoDelay, errExtended, errLookupFail, errSearchErr,
  errInvalidValue
}
enum  Tos {
  tosLowDelay = 0, tosThroughput, tosReliability, tosMinCost,
  tosInvalid
}
enum  Pending { pendingInput, pendingOutput, pendingError }
typedef enum Family Family
typedef enum Error Error
typedef enum Tos Tos
typedef enum Pending Pending

Public Member Functions

virtual ~Socket ()
 The socket base class may be "thrown" as a result of an error, and the "catcher" may then choose to destroy the object.
Socketoperator= (const Socket &from)
 Sockets may also be duplicated by the assignment operator.
virtual IPV4Host getIPV4Sender (tpport_t *port=NULL) const
 May be used to examine the origin of data waiting in the socket receive queue.
IPV4Host getSender (tpport_t *port=NULL) const
virtual IPV6Host getIPV6Sender (tpport_t *port=NULL) const
IPV4Host getIPV4Peer (tpport_t *port=NULL) const
 Get the host address and port of the socket this socket is connected to.
IPV4Host getPeer (tpport_t *port=NULL) const
IPV6Host getIPV6Peer (tpport_t *port=NULL) const
IPV4Host getIPV4Local (tpport_t *port=NULL) const
 Get the local address and port number this socket is currently bound to.
IPV4Host getLocal (tpport_t *port=NULL) const
IPV6Host getIPV6Local (tpport_t *port=NULL) const
IPV4Host getIPV4NAT (tpport_t *port=NULL) const
 Perform NAT table lookup for this socket.
IPV4Host getNAT (tpport_t *port) const
IPV6Host getIPV6NAT (tpport_t *port=NULL) const
void setCompletion (bool immediate)
 Used to specify blocking mode for the socket.
Error setLinger (bool linger)
 Enable lingering sockets on close.
Error setKeepAlive (bool enable)
 Set the keep-alive status of this socket and if keep-alive messages will be sent.
Error setTypeOfService (Tos service)
 Set packet scheduling on platforms which support ip quality of service conventions.
bool isConnected (void) const
 Can test to see if this socket is "connected", and hence whether a "catch" can safely call getPeer().
bool isActive (void) const
 Test to see if the socket is at least operating or if it is mearly initialized.
bool operator! () const
 Operator based testing to see if a socket is currently active.
bool isBroadcast (void) const
 Return if broadcast has been enabled for the specified socket.
bool isRouted (void) const
 Return if socket routing is enabled.
Error getErrorNumber (void) const
 Often used by a "catch" to fetch the last error of a thrown socket.
const char * getErrorString (void) const
 Often used by a "catch" to fetch the user set error string of a thrown socket, but only if EXTENDED error codes are used.
long getSystemError (void) const
const char * getSystemErrorString (void) const
virtual bool isPending (Pending pend, timeout_t timeout=TIMEOUT_INF)
 Get the status of pending operations.

Static Public Member Functions

static bool check (Family fam)
 See if a specific protocol family is available in the current runtime environment.

Protected Types

enum  State {
  INITIAL, AVAILABLE, BOUND, CONNECTED,
  CONNECTING, STREAM
}
typedef enum State State

Protected Member Functions

Error error (Error error, const char *err=NULL, long systemError=0) const
 This service is used to throw all socket errors which usually occur during the socket constructor.
void error (const char *err) const
 This service is used to throw application defined socket errors where the application specific error code is a string.
void setError (bool enable)
 This service is used to turn the error handler on or off for "throwing" exceptions by manipulating the thrown flag.
void endSocket (void)
 Used as the default destructor for ending a socket.
Error connectError (void)
 Used as a common handler for connection failure processing.
Error sendLimit (int limit=2048)
 Set the send limit.
Error receiveLimit (int limit=1)
 Set thr receive limit.
Error sendTimeout (timeout_t timer)
 Set the send timeout for sending raw network data.
Error receiveTimeout (timeout_t timer)
 Receive timeout for receiving raw network data.
Error sendBuffer (unsigned size)
 Set the protocol stack network kernel send buffer size associated with the socket.
Error receiveBuffer (unsigned size)
 Set the protocol stack network kernel receive buffer size associated with the socket.
Error bufferSize (unsigned size)
 Set the total protocol stack network kernel buffer size for both send and receive together.
Error setBroadcast (bool enable)
 Set the subnet broadcast flag for the socket.
Error setMulticastByFamily (bool enable, Family family=IPV4)
 Setting multicast binds the multicast interface used for the socket to the interface the socket itself has been implicitly bound to.
Error setLoopbackByFamily (bool enable, Family family=IPV4)
 Set the multicast loopback flag for the socket.
Error setTimeToLiveByFamily (unsigned char ttl, Family fam=IPV4)
 Set the multicast time to live for a multicast socket.
Error join (const IPV4Multicast &ia)
 Join a multicast group.
Error join (const IPV6Multicast &ia)
Error drop (const IPV4Multicast &ia)
 Drop membership from a multicast group.
Error drop (const IPV6Multicast &ia)
Error setRouting (bool enable)
 Set the socket routing to indicate if outgoing messages should bypass normal routing (set false).
Error setNoDelay (bool enable)
 Enable/disable delaying packets (Nagle algorithm)
 Socket (int domain, int type, int protocol=0)
 An unconnected socket may be created directly on the local machine.
 Socket (SOCKET fd)
 A socket object may be created from a file descriptor when that descriptor was created either through a socket() or accept() call.
 Socket ()
 Create an inactive socket object for base constructors.
 Socket (const Socket &source)
 A socket can also be constructed from an already existing Socket object.
ssize_t readLine (char *buf, size_t len, timeout_t timeout=0)
 Process a logical input line from a socket descriptor directly.
virtual ssize_t readData (void *buf, size_t len, char separator=0, timeout_t t=0)
 Read in a block of len bytes with specific separator.
virtual ssize_t writeData (const void *buf, size_t len, timeout_t t=0)
 Write a block of len bytes to socket.

Protected Attributes

struct {
   bool   thrown: 1
   bool   broadcast: 1
   bool   route: 1
   bool   keepalive: 1
   bool   loopback: 1
   bool   multicast: 1
   bool   completion: 1
   bool   linger: 1
   unsigned   ttl: 8
flags
SOCKET volatile so
 the actual socket descriptor, in Windows, unlike posix it *cannot* be used as an file descriptor that way madness lies -- jfc
State volatile state

Static Protected Attributes

static Mutex mutex

Friends

SOCKET dupSocket (SOCKET s, Socket::State state)

Detailed Description

The Socket is used as the base for all Internet protocol services under Common C++.

A socket is a system resource (or winsock descriptor) that occupies a specific port address (and may be bound to a specific network interface) on the local machine. The socket may also be directly connected to a specific socket on a remote internet host.

This base class is not directly used, but is provided to offer properties common to other Common C++ socket classes, including the socket exception model and the ability to set socket properties such as QoS, "sockopts" properties like Dont-Route and Keep-Alive, etc.

Author:
David Sugar <dyfet@ostel.com> base class of all sockets.
Examples:

tcpthread.cpp.


Member Typedef Documentation

typedef enum Error ost::Socket::Error

Reimplemented in ost::URLStream.

typedef enum State ost::Socket::State [protected]
typedef enum Tos ost::Socket::Tos

Member Enumeration Documentation

Enumerator:
errSuccess 
errCreateFailed 
errCopyFailed 
errInput 
errInputInterrupt 
errResourceFailure 
errOutput 
errOutputInterrupt 
errNotConnected 
errConnectRefused 
errConnectRejected 
errConnectTimeout 
errConnectFailed 
errConnectInvalid 
errConnectBusy 
errConnectNoRoute 
errBindingFailed 
errBroadcastDenied 
errRoutingDenied 
errKeepaliveDenied 
errServiceDenied 
errServiceUnavailable 
errMulticastDisabled 
errTimeout 
errNoDelay 
errExtended 
errLookupFail 
errSearchErr 
errInvalidValue 

Reimplemented in ost::URLStream.

Enumerator:
IPV6 
IPV4 
Enumerator:
pendingInput 
pendingOutput 
pendingError 
enum ost::Socket::State [protected]
Enumerator:
INITIAL 
AVAILABLE 
BOUND 
CONNECTED 
CONNECTING 
STREAM 
Enumerator:
tosLowDelay 
tosThroughput 
tosReliability 
tosMinCost 
tosInvalid 

Constructor & Destructor Documentation

ost::Socket::Socket ( int  domain,
int  type,
int  protocol = 0 
) [protected]

An unconnected socket may be created directly on the local machine.

Sockets can occupy both the internet domain (AF_INET) and UNIX socket domain (AF_UNIX) under unix. The socket type (SOCK_STREAM, SOCK_DGRAM) and protocol may also be specified. If the socket cannot be created, an exception is thrown.

Parameters:
domainsocket domain to use.
typebase type and protocol family of the socket.
protocolspecific protocol to apply.
ost::Socket::Socket ( SOCKET  fd) [protected]

A socket object may be created from a file descriptor when that descriptor was created either through a socket() or accept() call.

This constructor is mostly for internal use.

Parameters:
fdfile descriptor of an already existing socket.
ost::Socket::Socket ( ) [protected]

Create an inactive socket object for base constructors.

ost::Socket::Socket ( const Socket source) [protected]

A socket can also be constructed from an already existing Socket object.

On POSIX systems, the socket file descriptor is dup()'d. On Win32, DuplicateHandle() is used.

Parameters:
sourceof existing socket to clone.
virtual ost::Socket::~Socket ( ) [virtual]

The socket base class may be "thrown" as a result of an error, and the "catcher" may then choose to destroy the object.

By assuring the socket base class is a virtual destructor, we can assure the full object is properly terminated.


Member Function Documentation

Error ost::Socket::bufferSize ( unsigned  size) [protected]

Set the total protocol stack network kernel buffer size for both send and receive together.

Returns:
errSuccess on success
Parameters:
sizeof buffer.
static bool ost::Socket::check ( Family  fam) [static]

See if a specific protocol family is available in the current runtime environment.

Returns:
true if family available.
Error ost::Socket::connectError ( void  ) [protected]

Used as a common handler for connection failure processing.

Returns:
correct failure code to apply.
Error ost::Socket::drop ( const IPV4Multicast ia) [protected]

Drop membership from a multicast group.

Returns:
0 (errSuccess) on success, else error code.
Parameters:
iaaddress of multicast group to drop.

Reimplemented in ost::UDPReceive.

Referenced by ost::UDPReceive::drop().

Error ost::Socket::drop ( const IPV6Multicast ia) [protected]

Reimplemented in ost::UDPReceive.

void ost::Socket::endSocket ( void  ) [protected]

Used as the default destructor for ending a socket.

This will cleanly terminate the socket connection. It is provided for use in derived virtual destructors.

Referenced by ost::UDPReceive::endReceiver(), and ost::UDPTransmit::endTransmitter().

void ost::Socket::error ( const char *  err) const [inline, protected]

This service is used to throw application defined socket errors where the application specific error code is a string.

Parameters:
errstring or message to pass.

References error().

Referenced by error().

Error ost::Socket::error ( Error  error,
const char *  err = NULL,
long  systemError = 0 
) const [protected]

This service is used to throw all socket errors which usually occur during the socket constructor.

Parameters:
errordefined socket error id.
errstring or message to pass.
systemErrorthe system error# that caused the error
Error ost::Socket::getErrorNumber ( void  ) const [inline]

Often used by a "catch" to fetch the last error of a thrown socket.

Returns:
error number of Error error.
Examples:
tcpthread.cpp.
const char* ost::Socket::getErrorString ( void  ) const [inline]

Often used by a "catch" to fetch the user set error string of a thrown socket, but only if EXTENDED error codes are used.

Returns:
string for error message.
IPV4Host ost::Socket::getIPV4Local ( tpport_t port = NULL) const

Get the local address and port number this socket is currently bound to.

Parameters:
portptr to port number on local host.
Returns:
host address of interface this socket is bound to.

Referenced by ost::TCPSocket::getLocal().

IPV4Host ost::Socket::getIPV4NAT ( tpport_t port = NULL) const

Perform NAT table lookup for this socket.

Used to allow an application to know the original ip:port pair the the client "thinks" it is connecting to. Used mostly to transparently impersonate a remote server/service.

On error, 0.0.0.0:0 is returned and one of the following error codes is set: errServiceUnavailable - if nat is not supported on the current platform or if it was not compiled; errLookupFail - if the nat syscall failed for some reason (extended error code); errSearchErr - if the socket does not have nat information (i.e. is not nated).

NAT lookup is supported on NetFilter for ipv4 and ipv6 (Linux), IPFilter for ipv4 (Solaris, *BSD except OpenBSD, HP-UX, etc.) and Packet Filter for ipv4 and ipv6 (OpenBSD). When using IPFilter or Packet Filter, the first NAT lookup must be performed as root (the NAT device is read only for root and is opened once, unless an error occurs). Permissions on the nat device may be changed to solve this.

Warning:
When using IPFilter and Packet Filter, application data model must be the same as the running kernel (32/64 bits).
Parameters:
portptr to NATed port number on local host.
Returns:
NATed host address that this socket is related to.
IPV4Host ost::Socket::getIPV4Peer ( tpport_t port = NULL) const

Get the host address and port of the socket this socket is connected to.

If the socket is currently not in a connected state, then a host address of 0.0.0.0 is returned.

Parameters:
portptr to port number of remote socket.
Returns:
host address of remote socket.

Reimplemented in ost::UDPSocket.

virtual IPV4Host ost::Socket::getIPV4Sender ( tpport_t port = NULL) const [virtual]

May be used to examine the origin of data waiting in the socket receive queue.

This can tell a TCP server where pending "connect" requests are coming from, or a UDP socket where it's next packet arrived from.

Parameters:
portptr to port number of sender.
Returns:
host address, test with "isInetAddress()".

Reimplemented in ost::DCCPSocket.

Referenced by ost::TCPSocket::getRequest().

IPV6Host ost::Socket::getIPV6Local ( tpport_t port = NULL) const
IPV6Host ost::Socket::getIPV6NAT ( tpport_t port = NULL) const
IPV6Host ost::Socket::getIPV6Peer ( tpport_t port = NULL) const

Reimplemented in ost::UDPSocket.

virtual IPV6Host ost::Socket::getIPV6Sender ( tpport_t port = NULL) const [virtual]

Reimplemented in ost::DCCPSocket.

Referenced by ost::TCPV6Socket::getRequest().

IPV4Host ost::Socket::getLocal ( tpport_t port = NULL) const [inline]

Reimplemented in ost::TCPSocket, and ost::TCPV6Socket.

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

Reimplemented in ost::UDPSocket.

Examples:
tcp.cpp, and tcpthread.cpp.
IPV4Host ost::Socket::getSender ( tpport_t port = NULL) const [inline]
long ost::Socket::getSystemError ( void  ) const [inline]
const char* ost::Socket::getSystemErrorString ( void  ) const
bool ost::Socket::isActive ( void  ) const

Test to see if the socket is at least operating or if it is mearly initialized.

"initialized" sockets may be the result of failed constructors.

Returns:
true if not in initial state.
bool ost::Socket::isBroadcast ( void  ) const [inline]

Return if broadcast has been enabled for the specified socket.

Returns:
true if broadcast socket.
bool ost::Socket::isConnected ( void  ) const

Can test to see if this socket is "connected", and hence whether a "catch" can safely call getPeer().

Of course, an unconnected socket will return a 0.0.0.0 address from getPeer() as well.

Returns:
true when socket is connected to a peer.
virtual bool ost::Socket::isPending ( Pending  pend,
timeout_t  timeout = TIMEOUT_INF 
) [virtual]

Get the status of pending operations.

This can be used to examine if input or output is waiting, or if an error has occured on the descriptor.

Returns:
true if ready, false on timeout.
Parameters:
pendready check to perform.
timeoutin milliseconds, inf. if not specified.

Reimplemented in ost::TCPStream, ost::SimpleTCPStream, and ost::UnixStream.

Referenced by ost::UDPReceive::isInputReady(), ost::UDPTransmit::isOutputReady(), ost::UnixSocket::isPendingConnection(), ost::TCPV6Socket::isPendingConnection(), ost::TCPSocket::isPendingConnection(), ost::DCCPSocket::isPendingConnection(), and ost::UDPReceive::isPendingReceive().

bool ost::Socket::isRouted ( void  ) const [inline]

Return if socket routing is enabled.

Returns:
true if routing enabled.
Error ost::Socket::join ( const IPV4Multicast ia) [protected]

Join a multicast group.

Returns:
0 (errSuccess) on success, else error code.
Parameters:
iaaddress of multicast group to join.

Reimplemented in ost::UDPReceive.

Referenced by ost::UDPReceive::join().

Error ost::Socket::join ( const IPV6Multicast ia) [protected]

Reimplemented in ost::UDPReceive.

bool ost::Socket::operator! ( ) const

Operator based testing to see if a socket is currently active.

Reimplemented in ost::unixstream.

Socket& ost::Socket::operator= ( const Socket from)

Sockets may also be duplicated by the assignment operator.

virtual ssize_t ost::Socket::readData ( void *  buf,
size_t  len,
char  separator = 0,
timeout_t  t = 0 
) [protected, virtual]

Read in a block of len bytes with specific separator.

Can be zero, or any other char. If \n or \r, it's treated just like a readLine(). Otherwise it looks for the separator.

Parameters:
bufpointer to byte allocation.
lenmaximum length to read.
separatorseparator for a particular ASCII character
ttimeout for pending data in milliseconds.
Returns:
number of bytes actually read.

Reimplemented in ost::SSLStream.

ssize_t ost::Socket::readLine ( char *  buf,
size_t  len,
timeout_t  timeout = 0 
) [protected]

Process a logical input line from a socket descriptor directly.

Parameters:
bufpointer to string.
lenmaximum length to read.
timeoutfor pending data in milliseconds.
Returns:
number of bytes actually read.

Reimplemented in ost::SSLStream.

Error ost::Socket::receiveBuffer ( unsigned  size) [protected]

Set the protocol stack network kernel receive buffer size associated with the socket.

Returns:
errSuccess on success, or error.
Parameters:
sizeof buffer in bytes.
Error ost::Socket::receiveLimit ( int  limit = 1) [protected]

Set thr receive limit.

Error ost::Socket::receiveTimeout ( timeout_t  timer) [protected]

Receive timeout for receiving raw network data.

Returns:
errSuccess if set.
Parameters:
timervalue in milliseconds.
Error ost::Socket::sendBuffer ( unsigned  size) [protected]

Set the protocol stack network kernel send buffer size associated with the socket.

Returns:
errSuccess on success, or error.
Parameters:
sizeof buffer in bytes.
Error ost::Socket::sendLimit ( int  limit = 2048) [protected]

Set the send limit.

Error ost::Socket::sendTimeout ( timeout_t  timer) [protected]

Set the send timeout for sending raw network data.

Returns:
errSuccess if set.
Parameters:
timervalue in millisec.
Error ost::Socket::setBroadcast ( bool  enable) [protected]

Set the subnet broadcast flag for the socket.

This enables sending to a subnet and may require special image privileges depending on the operating system.

Returns:
0 (errSuccess) on success, else error code.
Parameters:
enablewhen set to true.

Reimplemented in ost::UDPTransmit.

Referenced by ost::UDPTransmit::setBroadcast().

void ost::Socket::setCompletion ( bool  immediate)

Used to specify blocking mode for the socket.

A socket can be made non-blocking by setting setCompletion(false) or set to block on all access with setCompletion(true). I do not believe this form of non-blocking socket I/O is supported in winsock, though it provides an alternate asynchronous set of socket services.

Parameters:
immediatemode specify socket I/O call blocking mode.
void ost::Socket::setError ( bool  enable) [inline, protected]

This service is used to turn the error handler on or off for "throwing" exceptions by manipulating the thrown flag.

Parameters:
enabletrue to enable handler.
Error ost::Socket::setKeepAlive ( bool  enable)

Set the keep-alive status of this socket and if keep-alive messages will be sent.

Returns:
0 on success.
Parameters:
enablekeep alive messages.
Error ost::Socket::setLinger ( bool  linger)

Enable lingering sockets on close.

Parameters:
lingerspecify linger enable.
Error ost::Socket::setLoopbackByFamily ( bool  enable,
Family  family = IPV4 
) [protected]

Set the multicast loopback flag for the socket.

Loopback enables a socket to hear what it is sending.

Returns:
0 (errSuccess) on success, else error code.
Parameters:
enablewhen set to true.
familyof protocol.

Referenced by ost::UDPSocket::setLoopback().

Error ost::Socket::setMulticastByFamily ( bool  enable,
Family  family = IPV4 
) [protected]

Setting multicast binds the multicast interface used for the socket to the interface the socket itself has been implicitly bound to.

It is also used as a check flag to make sure multicast is enabled before multicast operations are used.

Returns:
0 (errSuccess) on success, else error code.
Parameters:
enablewhen set to true.
familyof protocol.

Referenced by ost::UDPReceive::setMulticast(), ost::UDPTransmit::setMulticast(), and ost::UDPSocket::setMulticast().

Error ost::Socket::setNoDelay ( bool  enable) [protected]

Enable/disable delaying packets (Nagle algorithm)

Returns:
0 on success.
Parameters:
enabledisable Nagle algorithm when set to true.
Error ost::Socket::setRouting ( bool  enable) [protected]

Set the socket routing to indicate if outgoing messages should bypass normal routing (set false).

Returns:
0 on success.
Parameters:
enablenormal routing when set to true.

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

Referenced by ost::UDPReceive::setRouting(), and ost::UDPTransmit::setRouting().

Error ost::Socket::setTimeToLiveByFamily ( unsigned char  ttl,
Family  fam = IPV4 
) [protected]

Set the multicast time to live for a multicast socket.

Returns:
0 (errSuccess) on success, else error code.
Parameters:
ttltime to live.
famfamily of protocol.

Referenced by ost::UDPTransmit::setTimeToLive(), and ost::UDPSocket::setTimeToLive().

Error ost::Socket::setTypeOfService ( Tos  service)

Set packet scheduling on platforms which support ip quality of service conventions.

This effects how packets in the queue are scheduled through the interface.

Returns:
0 on success, error code on failure.
Parameters:
servicetype of service enumerated type.

Reimplemented in ost::UDPTransmit.

Referenced by ost::UDPTransmit::setTypeOfService().

virtual ssize_t ost::Socket::writeData ( const void *  buf,
size_t  len,
timeout_t  t = 0 
) [protected, virtual]

Write a block of len bytes to socket.

Parameters:
bufpointer to byte allocation.
lenmaximum length to write.
ttimeout for pending data in milliseconds.
Returns:
number of bytes actually written.

Friends And Related Function Documentation

SOCKET dupSocket ( SOCKET  s,
Socket::State  state 
) [friend]

Member Data Documentation

struct { ... } ost::Socket::flags [protected]
Mutex ost::Socket::mutex [static, protected]
Examples:
tcpthread.cpp.
SOCKET volatile ost::Socket::so [protected]

the actual socket descriptor, in Windows, unlike posix it *cannot* be used as an file descriptor that way madness lies -- jfc

State volatile ost::Socket::state [protected]
unsigned ost::Socket::ttl

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