KNetwork::KSocketBase Class Reference

#include <k3socketbase.h>

Inheritance diagram for KNetwork::KSocketBase:

Public Types
enum	SocketError {   NoError = 0, LookupFailure, AddressInUse, AlreadyCreated,   AlreadyBound, AlreadyConnected, NotConnected, NotBound,   NotCreated, WouldBlock, ConnectionRefused, ConnectionTimedOut,   InProgress, NetFailure, NotSupported, Timeout,   UnknownError, RemotelyDisconnected }
enum	SocketOptions {   Blocking = 0x01, AddressReuseable = 0x02, IPv6Only = 0x04, Keepalive = 0x08,   Broadcast = 0x10, NoDelay = 0x20 }

Public Member Functions
	KSocketBase ()
virtual	~KSocketBase ()
bool	addressReuseable () const
bool	blocking () const
bool	broadcast () const
SocketError	error () const
QString	errorString () const
bool	isIPv6Only () const
QMutex *	mutex () const
bool	noDelay () const
virtual bool	setAddressReuseable (bool enable)
virtual bool	setBlocking (bool enable)
virtual bool	setBroadcast (bool enable)
virtual bool	setIPv6Only (bool enable)
virtual bool	setNoDelay (bool enable)
int	setRequestedCapabilities (int add, int remove=0)
virtual void	setSocketDevice (KSocketDevice *device)
KSocketDevice *	socketDevice () const

Static Public Member Functions
static QString	errorString (SocketError code)
static bool	isFatalError (int code)

Protected Member Functions
bool	hasDevice () const
void	resetError ()
void	setError (SocketError error)
virtual bool	setSocketOptions (int opts)
virtual int	socketOptions () const

Detailed Description

Basic socket functionality.

This class provides the basic socket functionlity for descended classes. Socket classes are thread-safe and provide a recursive mutex should it be needed.

Note

This class is abstract.

Author

Thiago Macieira thiag.nosp@m.o@kd.nosp@m.e.org

Deprecated:

Use KSocketFactory or KLocalSocket instead

Definition at line 85 of file k3socketbase.h.

Member Enumeration Documentation

enum KNetwork::KSocketBase::SocketError

Possible socket error codes.

This is a list of possible error conditions that socket classes may be expected to find.

• NoError: no error has been detected
• LookupFailure: if a name lookup has failed
• AddressInUse: address is already in use
• AlreadyBound: cannot bind again
• AlreadyCreated: cannot recreate the socket
• NotBound: operation required socket to be bound and it isn't
• NotCreated: operation required socket to exist and it doesn't
• WouldBlock: requested I/O operation would block
• ConnectionRefused: connection actively refused
• ConnectionTimedOut: connection timed out
• InProgress: operation (connection) is already in progress
• NetFailure: a network failure occurred (no route, host down, host unreachable or similar)
• NotSupported: requested operation is not supported
• Timeout: a timed operation timed out
• UnknownError: an unknown/unexpected error has happened
• RemotelyDisconnected: when a connection is disconnected by the other end (since 3.4)

See also

error, errorString

Enumerator
NoError
LookupFailure
AddressInUse
AlreadyCreated
AlreadyBound
AlreadyConnected
NotConnected
NotBound
NotCreated
WouldBlock
ConnectionRefused
ConnectionTimedOut
InProgress
NetFailure
NotSupported
Timeout
UnknownError
RemotelyDisconnected

Definition at line 143 of file k3socketbase.h.

enum KNetwork::KSocketBase::SocketOptions

Possible socket options.

These are the options that may be set on a socket:

• Blocking: whether the socket shall operate in blocking or non-blocking mode. This flag defaults to on. See setBlocking().
• AddressReusable: whether the address used by this socket will be available for reuse by other sockets. This flag defaults to off. See setAddressReuseable().
• IPv6Only: whether an IPv6 socket will accept IPv4 connections through a mapped address. This flag defaults to off. See setIPv6Only().
• KeepAlive: whether TCP should send keepalive probes when a connection has gone idle for far too long.
• Broadcast: whether this socket is allowed to send broadcast packets and will receive packets sent to broadcast.
• NoDelay: disable the Nagle algorithm for socket types that support it.

Enumerator
Blocking
AddressReuseable
IPv6Only
Keepalive
Broadcast
NoDelay

Definition at line 108 of file k3socketbase.h.

Constructor & Destructor Documentation

KSocketBase::KSocketBase

(

)

Default constructor.

Definition at line 68 of file k3socketbase.cpp.

KSocketBase::~KSocketBase ( )

virtual

Destructor.

Definition at line 80 of file k3socketbase.cpp.

Member Function Documentation

bool KSocketBase::addressReuseable

(

)

const

Retrieves this socket's address reuseability flag.

Returns

true if this socket's address can be reused, false if it can't.

Definition at line 112 of file k3socketbase.cpp.

bool KSocketBase::blocking

(

)

const

Retrieves this socket's blocking mode.

Returns

true if this socket is/will be operated in blocking mode, false if non-blocking.

Definition at line 102 of file k3socketbase.cpp.

bool KSocketBase::broadcast

(

)

const

Retrieves this socket's Broadcast flag.

Returns

true if this socket can send and receive broadcast packets, false if it can't.

Definition at line 132 of file k3socketbase.cpp.

KSocketBase::SocketError KSocketBase::error

(

)

const

Retrieves the socket error code.

See also

errorString

Definition at line 197 of file k3socketbase.cpp.

QString KSocketBase::errorString

(

)

const

Returns the error string corresponding to this error condition.

Definition at line 202 of file k3socketbase.cpp.

QString KSocketBase::errorString ( KSocketBase::SocketError  code )

static

Returns the string describing the given error code, i18n'ed.

Parameters

code	the error code

Definition at line 208 of file k3socketbase.cpp.

bool KSocketBase::hasDevice ( ) const

protected

Returns true if the socket device has been initialised in this object, either by calling socketDevice() or setSocketDevice()

Definition at line 182 of file k3socketbase.cpp.

bool KSocketBase::isFatalError ( int  code )

static

Returns true if the given error code is a fatal one, false otherwise.

The parameter here is of type int so that casting isn't necessary when using the parameter to signal QClientSocketBase::gotError.

Parameters

code	the code to test

Definition at line 301 of file k3socketbase.cpp.

bool KSocketBase::isIPv6Only

(

)

const

Retrieves this socket's IPv6 Only flag.

Returns

true if this socket will ignore IPv4-compatible and IPv4-mapped addresses, false if it will accept them.

Definition at line 122 of file k3socketbase.cpp.

QMutex * KSocketBase::mutex

(

)

const

Returns the internal mutex for this class.

Note on multithreaded use of sockets: the socket classes are thread-safe by design, but you should be aware of problems regarding socket creation, connection and destruction in multi-threaded programs. The classes are guaranteed to work while the socket exists, but it's not wise to call connect in multiple threads.

Also, this mutex must be unlocked before the object is destroyed, which means you cannot use it to guard against other threads accessing the object while destroying it. You must ensure there are no further references to this object when deleting it.

Definition at line 320 of file k3socketbase.cpp.

bool KSocketBase::noDelay

(

)

const

Retrieves this socket's NoDelay flag.

Returns

true if this socket's Nagle algorithm is disabled.

Definition at line 142 of file k3socketbase.cpp.

void KSocketBase::resetError ( )

protected

Resets the socket error code and the I/O Device's status.

Definition at line 192 of file k3socketbase.cpp.

bool KSocketBase::setAddressReuseable ( bool  enable )

virtual

Sets this socket's address reuseable flag.

When the address reuseable flag is active, the address used by this socket is left reuseable for other sockets to bind. If the flag is not active, no other sockets may reuse the same address.

The default implementation toggles the AddressReuseable flag with the current socket options and calls setSocketOptions().

Parameters

enable

whether to set the flag on or off

Returns

true if setting this flag was successful

Definition at line 107 of file k3socketbase.cpp.

bool KSocketBase::setBlocking ( bool  enable )

virtual

Sets this socket's blocking mode.

In blocking operation, all I/O functions are susceptible to blocking – i.e., will not return unless the I/O can be satisfied. In non-blocking operation, if the I/O would block, the function will return an error and set the corresponding error code.

The default implementation toggles the Blocking flag with the current socket options and calls setSocketOptions().

Parameters

enable

whether to set this socket to blocking mode

Returns

whether setting this value was successful; it is NOT the final blocking mode.

Definition at line 97 of file k3socketbase.cpp.

bool KSocketBase::setBroadcast ( bool  enable )

virtual

Sets this socket Broadcast flag.

Datagram-oriented sockets cannot normally send packets to broadcast addresses, nor will they receive packets that were sent to a broadcast address. To do so, you need to enable the Broadcast flag.

This option has no effect on stream-oriented sockets.

Returns

true if setting this flag was successful.

Definition at line 127 of file k3socketbase.cpp.

void KSocketBase::setError ( SocketError  error )

protected

Sets the socket's error code.

Parameters

error

the error code

Definition at line 187 of file k3socketbase.cpp.

bool KSocketBase::setIPv6Only ( bool  enable )

virtual

Sets this socket's IPv6 Only flag.

When this flag is on, an IPv6 socket will only accept, connect, send to or receive from IPv6 addresses. When it is off, it will also talk to IPv4 addresses through v4-mapped addresses.

This option has no effect on non-IPv6 sockets.

The default implementation toggles the IPv6Only flag with the current socket options and calls setSocketOptions().

Parameters

enable

whether to set the flag on or off

Returns

true if setting this flag was successful

Definition at line 117 of file k3socketbase.cpp.

bool KSocketBase::setNoDelay ( bool  enable )

virtual

Sets this socket's NoDelay flag.

Stream-oriented protocols, like TCP, have an internal algorithm (called Nagle's algorithm) that collects data in a buffer so that the transmission doesn't occur after every single write operation. The side-effect is that the transmission of short messages is delayed.

Setting NoDelay to 'true' will disable this algorithm.

Returns

true if setting this flag was successful.

Definition at line 137 of file k3socketbase.cpp.

int KSocketBase::setRequestedCapabilities	(	int	add,
		int	remove = 0
	)

Sets the internally requested capabilities for a socket device.

Most socket classes can use any back-end implementation. However, a few may require specific capabilities not provided in the default implementation. By using this function, derived classes can request that a backend with those capabilities be created when necessary.

For the possible flags, see KSocketDevice::Capabilities. However, note that only the Can* flags make sense in this context.

Note

Since socketDevice must always return a valid backend object, it is is possible that the created device does not conform to all requirements requested. Implementations sensitive to this fact should test the object returned by socketDevice() (through KSocketDevice::capabilities(), for instance) the availability.

Parameters

add	mask of KSocketDevice::Capabilities to add
remove	mask of bits to remove from the requirements

Returns

the current mask of requested capabilities

Definition at line 175 of file k3socketbase.cpp.

void KSocketBase::setSocketDevice ( KSocketDevice *  device )

virtual

Sets the socket implementation to be used on this socket.

Note: it is an error to set this if the socket device has already been set once.

This function is provided virtual so that derived classes can catch the setting of a device and properly set their own states and internal variables. The parent class must be called.

This function is called by socketDevice() above when the socket is first created.

Reimplemented in KNetwork::KActiveSocketBase, and KNetwork::KBufferedSocket.

Definition at line 168 of file k3socketbase.cpp.

bool KSocketBase::setSocketOptions ( int  opts )

protectedvirtual

Set the given socket options.

The default implementation does nothing but store the mask internally. Descended classes must override this function to achieve functionality and must also call this implementation.

Parameters

opts	a mask of SocketOptions or-ed bits of options to set or unset

Returns

true on success

Note

this function sets the options corresponding to the bits enabled in opts but will also unset the optiosn corresponding to the bits not set.

Reimplemented in KNetwork::KServerSocket, KNetwork::KSocketDevice, KNetwork::KClientSocketBase, and KNetwork::KBufferedSocket.

Definition at line 86 of file k3socketbase.cpp.

KSocketDevice * KSocketBase::socketDevice

(

)

const

Retrieves the socket implementation used on this socket.

This function creates the device if none has been set using the default factory.

Definition at line 148 of file k3socketbase.cpp.

int KSocketBase::socketOptions ( ) const

protectedvirtual

Retrieves the socket options that have been set.

The default implementation just retrieves the mask from an internal variable. Descended classes may choose to override this function to read the values from the operating system.

Returns

the mask of the options set

Definition at line 92 of file k3socketbase.cpp.

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

• k3socketbase.h
• k3socketbase.cpp