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#include "q3socketdevice.h"

#ifndef QT_NO_NETWORK

#include "qwindowdefs.h"

#include <string.h>

QT_BEGIN_NAMESPACE

//#define Q3SOCKETDEVICE_DEBUG

class Q3SocketDevicePrivate

{

public:

    Q3SocketDevicePrivate( Q3SocketDevice::Protocol p )

	: protocol(p)

    { }

    Q3SocketDevice::Protocol protocol;

};

/*!

    \class Q3SocketDevice

    \brief The Q3SocketDevice class provides a platform-independent low-level socket API.

    \compat

    \reentrant

    This class provides a low level API for working with sockets.  Users of

    this class are assumed to have networking experience. For most users the

    Q3Socket class provides a much easier and high level alternative, but

    certain things (like UDP) can't be done with Q3Socket and if you need a

    platform-independent API for those, Q3SocketDevice is the right choice.

    The essential purpose of the class is to provide a QIODevice that

    works on sockets, wrapped in a platform-independent API.

    When calling connect() or bind(), Q3SocketDevice detects the

    protocol family (IPv4, IPv6) automatically. Passing the protocol

    family to Q3SocketDevice's constructor or to setSocket() forces

    creation of a socket device of a specific protocol. If not set, the

    protocol will be detected at the first call to connect() or bind().

    \sa Q3Socket, QSocketNotifier, QHostAddress

*/

/*!

    \enum Q3SocketDevice::Protocol

    This enum type describes the protocol family of the socket. Possible values

    are:

    \value IPv4 The socket is an IPv4 socket.

    \value IPv6 The socket is an IPv6 socket.

    \value Unknown The protocol family of the socket is not known. This can

	   happen if you use Q3SocketDevice with an already existing socket; it

	   tries to determine the protocol family, but this can fail if the

	   protocol family is not known to Q3SocketDevice.

    \sa protocol() setSocket()

*/

/*!

    \enum Q3SocketDevice::Error

    This enum type describes the error states of Q3SocketDevice.

    \value NoError  No error has occurred.

    \value AlreadyBound  The device is already bound, according to bind().

    \value Inaccessible  The operating system or firewall prohibited

			the action.

    \value NoResources  The operating system ran out of a resource.

    \value InternalError  An internal error occurred in Q3SocketDevice.

    \value Impossible  An attempt was made to do something which makes

    no sense. For example:

    \snippet doc/src/snippets/code/src_qt3support_network_q3socketdevice.cpp 0

    The libc ::close() closes the socket, but Q3SocketDevice is not aware

    of this. So when you call writeBlock(), the impossible happens.

    \value NoFiles  The operating system will not let Q3SocketDevice open

    another file.

    \value ConnectionRefused  A connection attempt was rejected by the

    peer.

    \value NetworkFailure  There is a network failure.

    \value UnknownError  The operating system did something

    unexpected.

    \omitvalue Bug

*/

/*!

    \enum Q3SocketDevice::Type

    This enum type describes the type of the socket:

    \value Stream  a stream socket (TCP, usually)

    \value Datagram  a datagram socket (UDP, usually)

*/

/*!

    Creates a Q3SocketDevice object for the existing socket \a socket.

    The \a type argument must match the actual socket type; use \c

    Q3SocketDevice::Stream for a reliable, connection-oriented TCP

    socket, or Q3SocketDevice::Datagram for an unreliable,

    connectionless UDP socket.

*/

Q3SocketDevice::Q3SocketDevice( int socket, Type type )

    : fd( socket ), t( type ), p( 0 ), pp( 0 ), e( NoError ),

      d(new Q3SocketDevicePrivate(Unknown))

{

#if defined(Q3SOCKETDEVICE_DEBUG)

    qDebug( "Q3SocketDevice: Created Q3SocketDevice %p (socket %x, type %d)",

	   this, socket, type );

#endif

    init();

    setSocket( socket, type );

}

/*!

    Creates a Q3SocketDevice object for a stream or datagram socket.

    The \a type argument must be either Q3SocketDevice::Stream for a

    reliable, connection-oriented TCP socket, or \c

    Q3SocketDevice::Datagram for an unreliable UDP socket.

    The socket is created as an IPv4 socket.

    \sa blocking() protocol()

*/

Q3SocketDevice::Q3SocketDevice( Type type )

    : fd( -1 ), t( type ), p( 0 ), pp( 0 ), e( NoError ),

      d(new Q3SocketDevicePrivate(IPv4))

{

#if defined(Q3SOCKETDEVICE_DEBUG)

    qDebug( "Q3SocketDevice: Created Q3SocketDevice object %p, type %d",

	    this, type );

#endif

    init();

    setSocket( createNewSocket(), type );

}

/*!

    Creates a Q3SocketDevice object for a stream or datagram socket.

    The \a type argument must be either Q3SocketDevice::Stream for a

    reliable, connection-oriented TCP socket, or \c

    Q3SocketDevice::Datagram for an unreliable UDP socket.

    The \a protocol indicates whether the socket should be of type IPv4

    or IPv6. Passing \c Unknown is not meaningful in this context and you

    should avoid using (it creates an IPv4 socket, but your code is not easily

    readable).

    The argument \a dummy is necessary for compatibility with some

    compilers.

    \sa blocking() protocol()

*/

Q3SocketDevice::Q3SocketDevice( Type type, Protocol protocol, int )

    : fd( -1 ), t( type ), p( 0 ), pp( 0 ), e( NoError ),

      d(new Q3SocketDevicePrivate(protocol))

{

#if defined(Q3SOCKETDEVICE_DEBUG)

    qDebug( "Q3SocketDevice: Created Q3SocketDevice object %p, type %d",

	    this, type );

#endif

    init();

    setSocket( createNewSocket(), type );

}

/*!

    Destroys the socket device and closes the socket if it is open.

*/

Q3SocketDevice::~Q3SocketDevice()

{

    close();

    delete d;

    d = 0;

#if defined(Q3SOCKETDEVICE_DEBUG)

    qDebug( "Q3SocketDevice: Destroyed Q3SocketDevice %p", this );

#endif

}

/*!

    Returns true if this is a valid socket; otherwise returns false.

    \sa socket()

*/

bool Q3SocketDevice::isValid() const

{

    return fd != -1;

}

/*!

    \fn Type Q3SocketDevice::type() const

    Returns the socket type which is either Q3SocketDevice::Stream

    or Q3SocketDevice::Datagram.

    \sa socket()

*/

Q3SocketDevice::Type Q3SocketDevice::type() const

{

    return t;

}

/*!

    Returns the socket's protocol family, which is one of \c Unknown, \c IPv4,

    or \c IPv6.

    Q3SocketDevice either creates a socket with a well known protocol family or

    it uses an already existing socket. In the first case, this function

    returns the protocol family it was constructed with. In the second case, it

    tries to determine the protocol family of the socket; if this fails, it

    returns \c Unknown.

    \sa Protocol setSocket()

*/

Q3SocketDevice::Protocol Q3SocketDevice::protocol() const

{

    if ( d->protocol == Unknown )

	d->protocol = getProtocol();

    return d->protocol;

}

/*!

    Returns the socket number, or -1 if it is an invalid socket.

    \sa isValid(), type()

*/

int Q3SocketDevice::socket() const

{

    return fd;

}

/*!

    Sets the socket device to operate on the existing socket \a

    socket.

    The \a type argument must match the actual socket type; use \c

    Q3SocketDevice::Stream for a reliable, connection-oriented TCP

    socket, or Q3SocketDevice::Datagram for an unreliable,

    connectionless UDP socket.

    Any existing socket is closed.

    \sa isValid(), close()

*/

void Q3SocketDevice::setSocket( int socket, Type type )

{

    if ( fd != -1 )			// close any open socket

	close();

#if defined(Q3SOCKETDEVICE_DEBUG)

    qDebug( "Q3SocketDevice::setSocket: socket %x, type %d", socket, type );

#endif

    t = type;

    fd = socket;

    d->protocol = Unknown;

    e = NoError;

    resetStatus();

    open( ReadWrite );

    fetchConnectionParameters();

}

/*!

    Opens the socket using the specified QIODevice file \a mode. This

    function is called from the Q3SocketDevice constructors and from

    the setSocket() function. You should not call it yourself.

    \sa close()

*/

bool Q3SocketDevice::open( OpenMode mode )

{

    if ( isOpen() || !isValid() )

	return false;

#if defined(Q3SOCKETDEVICE_DEBUG)

    qDebug( "Q3SocketDevice::open: mode %x", mode );

#endif

    setOpenMode( (mode & ReadWrite) | Unbuffered );

    return true;

}

/*!

    \fn bool Q3SocketDevice::open(int mode)

    \overload

*/

/*!

    The current Q3SocketDevice implementation does not buffer at all,

    so this is a no-op. This function always returns true.

*/

bool Q3SocketDevice::flush()

{

    return true;

}

/*!

    \reimp

    The size is meaningless for a socket, therefore this function returns 0.

*/

QIODevice::Offset Q3SocketDevice::size() const

{

    return 0;

}

/*!

    The read/write index is meaningless for a socket, therefore this

    function returns 0.

*/

QIODevice::Offset Q3SocketDevice::at() const

{

    return 0;

}

/*!

    The read/write index is meaningless for a socket, therefore this

    function does nothing and returns true.

    The \a offset parameter is ignored.

*/

bool Q3SocketDevice::at( Offset /* offset */ )

{

    return true;

}

/*!

    \reimp

    Returns true if no data is currently available at the socket;

    otherwise returns false.

*/

bool Q3SocketDevice::atEnd() const

{

    return bytesAvailable() <= 0;

}

/*!

    Returns true if the address of this socket can be used by other

    sockets at the same time, and false if this socket claims

    exclusive ownership.

    \sa setAddressReusable()

*/

bool Q3SocketDevice::addressReusable() const

{

    return option( ReuseAddress );

}

/*!

    Sets the address of this socket to be usable by other sockets too

    if \a enable is true, and to be used exclusively by this socket if

    \a enable is false.

    When a socket is reusable, other sockets can use the same port

    number (and IP address), which is generally useful. Of course

    other sockets cannot use the same

    (address,port,peer-address,peer-port) 4-tuple as this socket, so

    there is no risk of confusing the two TCP connections.

    \sa addressReusable()

*/

void Q3SocketDevice::setAddressReusable( bool enable )

{

    setOption( ReuseAddress, enable );

}

/*!

    Returns the size of the operating system receive buffer.

    \sa setReceiveBufferSize()

*/

int Q3SocketDevice::receiveBufferSize() const

{

    return option( ReceiveBuffer );

}

/*!

    Sets the size of the operating system receive buffer to \a size.

    The operating system receive buffer size effectively limits two

    things: how much data can be in transit at any one moment, and how

    much data can be received in one iteration of the main event loop.

    The default is operating system-dependent. A socket that receives

    large amounts of data is probably best with a buffer size of

    49152.

*/

void Q3SocketDevice::setReceiveBufferSize( uint size )

{

    setOption( ReceiveBuffer, size );

}

/*!

    Returns the size of the operating system send buffer.

    \sa setSendBufferSize()

*/

int Q3SocketDevice::sendBufferSize() const

{

    return option( SendBuffer );

}

/*!

    Sets the size of the operating system send buffer to \a size.

    The operating system send buffer size effectively limits how much

    data can be in transit at any one moment.

    The default is operating system-dependent. A socket that sends

    large amounts of data is probably best with a buffer size of

    49152.

*/

void Q3SocketDevice::setSendBufferSize( uint size )

{

    setOption( SendBuffer, size );

}

/*!

    Returns the port number of this socket device. This may be 0 for a

    while, but is set to something sensible as soon as a sensible

    value is available.

    Note that Qt always uses native byte order, i.e. 67 is 67 in Qt;

    there is no need to call htons().

*/

quint16 Q3SocketDevice::port() const

{

    return p;

}

/*!

    Returns the address of this socket device. This may be 0.0.0.0 for

    a while, but is set to something sensible as soon as a sensible

    value is available.

*/

QHostAddress Q3SocketDevice::address() const

{

    return a;

}

/*!

    Returns the first error seen.

*/

Q3SocketDevice::Error Q3SocketDevice::error() const

{

    return e;

}

/*!

    Allows subclasses to set the error state to \a err.

*/

void Q3SocketDevice::setError( Error err )

{

    e = err;

}

/*! \fn Q3SocketDevice::readBlock(char *data, Q_ULONG maxlen)

    Reads \a maxlen bytes from the socket into \a data and returns the