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Diffstat (limited to 'src/network/qsocket.cpp')
| -rw-r--r-- | src/network/qsocket.cpp | 1546 |
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diff --git a/src/network/qsocket.cpp b/src/network/qsocket.cpp new file mode 100644 index 0000000..492bc72 --- /dev/null +++ b/src/network/qsocket.cpp @@ -0,0 +1,1546 @@ +/**************************************************************************** +** +** Implementation of QSocket class. +** +** Created : 970521 +** +** Copyright (C) 1992-2008 Trolltech ASA. All rights reserved. +** +** This file is part of the network module of the Qt GUI Toolkit. +** +** This file may be used under the terms of the GNU General +** Public License versions 2.0 or 3.0 as published by the Free +** Software Foundation and appearing in the files LICENSE.GPL2 +** and LICENSE.GPL3 included in the packaging of this file. +** Alternatively you may (at your option) use any later version +** of the GNU General Public License if such license has been +** publicly approved by Trolltech ASA (or its successors, if any) +** and the KDE Free Qt Foundation. +** +** Please review the following information to ensure GNU General +** Public Licensing requirements will be met: +** http://trolltech.com/products/qt/licenses/licensing/opensource/. +** If you are unsure which license is appropriate for your use, please +** review the following information: +** http://trolltech.com/products/qt/licenses/licensing/licensingoverview +** or contact the sales department at sales@trolltech.com. +** +** This file may be used under the terms of the Q Public License as +** defined by Trolltech ASA and appearing in the file LICENSE.QPL +** included in the packaging of this file. Licensees holding valid Qt +** Commercial licenses may use this file in accordance with the Qt +** Commercial License Agreement provided with the Software. +** +** This file is provided "AS IS" with NO WARRANTY OF ANY KIND, +** INCLUDING THE WARRANTIES OF DESIGN, MERCHANTABILITY AND FITNESS FOR +** A PARTICULAR PURPOSE. Trolltech reserves all rights not granted +** herein. +** +**********************************************************************/ + +#include "qsocket.h" +#ifndef QT_NO_NETWORK +#include "qptrlist.h" +#include "qtimer.h" +#include "qsocketdevice.h" +#include "qdns.h" +#include "private/qinternal_p.h" + +#include <string.h> +#ifndef NO_ERRNO_H +#include <errno.h> +#endif + +//#define QSOCKET_DEBUG + +/* + Perhaps this private functionality needs to be refactored. + + Comment from Robert D Gatlin (Intel): + + It would be nice to have the functionality inherent in QSocket available + as a separate class as a standard part of the Qt library, something along + the line of: + + class QByteBuffer : public QIODevice { ... } + + The same class could/would be used within QSocket for the Read/Write + buffers. + + The above class could be used in the following way(s): + + buffer.open( IO_WriteOnly | IO_Append ); + buffer.writeBlock( a ); // a = QByteArray + buffer.close(); + + QByteArray b; + b.resize( buffer.size() ); + buffer.open( IO_ReadOnly ); + buffer.readBlock( b.data(), b.size() ); + buffer.close(); + + But would also be useable with QDataStream (via QIODevice) with: + + buffer.open( IO_WriteOnly | IO_Append ); + QDataStream is( &buffer ); + is << 100; + buffer.close(); + + buffer.open( IO_ReadOnly ); + QDataStream os( &buffer ); + Q_UINT32 x; + os >> x; + buffer.close(); + + The real usefulness is with any situations where data (QByteArray) arrives + incrementally (as in QSocket and filter case above). + + I tried using QBuffer, but QBuffer does not trim bytes from the front of + the buffer in cases like: + + QBuffer buf; + buf.open( IO_ReadOnly ); + QDataStream ds( &buf ); + Q_INT32 x; + ds >> x; + buf.close(); + + In the above case, buf.size() will be identical before and after the + operation with QDataStream. Based on the implementation of QBuffer, it + does not appear well suited for this kind of operation. +*/ + +// Private class for QSocket + +class QSocketPrivate { +public: + QSocketPrivate(); + ~QSocketPrivate(); + void closeSocket(); + void close(); + void connectionClosed(); + void setSocketDevice( QSocket *q, QSocketDevice *device ); + + QSocket::State state; // connection state + QString host; // host name + Q_UINT16 port; // host port + QSocketDevice *socket; // connection socket + QSocketNotifier *rsn, *wsn; // socket notifiers + QMembuf rba; // read buffer + Q_ULONG readBufferSize; // limit for the read buffer size + QPtrList<QByteArray> wba; // list of write bufs + QHostAddress addr; // connection address + QValueList<QHostAddress> addresses; // alternatives looked up + QIODevice::Offset wsize; // write total buf size + QIODevice::Offset windex; // write index +#ifndef QT_NO_DNS + QDns *dns4; + QDns *dns6; +#endif + static QPtrList<QSocket> sn_read_alreadyCalled; // used to avoid unwanted recursion + QValueList<QHostAddress> l4; + QValueList<QHostAddress> l6; +}; + +QPtrList<QSocket> QSocketPrivate::sn_read_alreadyCalled; + +QSocketPrivate::QSocketPrivate() + : state(QSocket::Idle), host(QString::fromLatin1("")), port(0), + socket(0), rsn(0), wsn(0), readBufferSize(0), wsize(0), windex(0) +{ +#ifndef QT_NO_DNS + dns4 = 0; + dns6 = 0; +#endif + wba.setAutoDelete( TRUE ); +} + +QSocketPrivate::~QSocketPrivate() +{ + close(); + delete socket; +#ifndef QT_NO_DNS + delete dns4; + delete dns6; +#endif +} + +void QSocketPrivate::closeSocket() +{ + // Order is important here - the socket notifiers must go away + // before the socket does, otherwise libc or the kernel will + // become unhappy. + delete rsn; + rsn = 0; + delete wsn; + wsn = 0; + if ( socket ) + socket->close(); +} + +void QSocketPrivate::close() +{ + closeSocket(); + wsize = 0; + rba.clear(); wba.clear(); + windex = 0; +} + +void QSocketPrivate::connectionClosed() +{ + // We keep the open state in case there's unread incoming data + state = QSocket::Idle; + closeSocket(); + wba.clear(); + windex = wsize = 0; +} + +void QSocketPrivate::setSocketDevice( QSocket *q, QSocketDevice *device ) +{ + delete socket; + delete rsn; + delete wsn; + + if ( device ) { + socket = device; + } else { + socket = new QSocketDevice( QSocketDevice::Stream, + ( addr.isIPv4Address() ? + QSocketDevice::IPv4 : + QSocketDevice::IPv6 ), 0 ); + socket->setBlocking( FALSE ); + socket->setAddressReusable( TRUE ); + } + + rsn = new QSocketNotifier( socket->socket(), + QSocketNotifier::Read, q, "read" ); + wsn = new QSocketNotifier( socket->socket(), + QSocketNotifier::Write, q, "write" ); + + QObject::connect( rsn, SIGNAL(activated(int)), q, SLOT(sn_read()) ); + rsn->setEnabled( FALSE ); + QObject::connect( wsn, SIGNAL(activated(int)), q, SLOT(sn_write()) ); + wsn->setEnabled( FALSE ); +} + +/*! + \class QSocket qsocket.h + \brief The QSocket class provides a buffered TCP connection. +\if defined(commercial) + It is part of the <a href="commercialeditions.html">Qt Enterprise Edition</a>. +\endif + + \ingroup io + \module network + + It provides a totally non-blocking QIODevice, and modifies and + extends the API of QIODevice with socket-specific code. + + Note that a QApplication must have been constructed before this + class can be used. + + The functions you're likely to call most are connectToHost(), + bytesAvailable(), canReadLine() and the ones it inherits from + QIODevice. + + connectToHost() is the most-used function. As its name implies, + it opens a connection to a named host. + + Most network protocols are either packet-oriented or + line-oriented. canReadLine() indicates whether a connection + contains an entire unread line or not, and bytesAvailable() + returns the number of bytes available for reading. + + The signals error(), connected(), readyRead() and + connectionClosed() inform you of the progress of the connection. + There are also some less commonly used signals. hostFound() is + emitted when connectToHost() has finished its DNS lookup and is + starting its TCP connection. delayedCloseFinished() is emitted + when close() succeeds. bytesWritten() is emitted when QSocket + moves data from its "to be written" queue into the TCP + implementation. + + There are several access functions for the socket: state() returns + whether the object is idle, is doing a DNS lookup, is connecting, + has an operational connection, etc. address() and port() return + the IP address and port used for the connection. The peerAddress() + and peerPort() functions return the IP address and port used by + the peer, and peerName() returns the name of the peer (normally + the name that was passed to connectToHost()). socketDevice() + returns a pointer to the QSocketDevice used for this socket. + + QSocket inherits QIODevice, and reimplements some functions. In + general, you can treat it as a QIODevice for writing, and mostly + also for reading. The match isn't perfect, since the QIODevice + API is designed for devices that are controlled by the same + machine, and an asynchronous peer-to-peer network connection isn't + quite like that. For example, there is nothing that matches + QIODevice::size() exactly. The documentation for open(), close(), + flush(), size(), at(), atEnd(), readBlock(), writeBlock(), + getch(), putch(), ungetch() and readLine() describes the + differences in detail. + + \warning QSocket is not suitable for use in threads. If you need + to uses sockets in threads use the lower-level QSocketDevice class. + + \warning Because Qt doesn't use the native socketstream + implementation on Mac OS X, QSocket has an implicit transfer + latency of 100ms. You can achieve lower latency on Mac OS X by + using QSocketDevice instead. + + \sa QSocketDevice, QHostAddress, QSocketNotifier +*/ + + +/*! + Creates a QSocket object in \c QSocket::Idle state. + + The \a parent and \a name arguments are passed on to the QObject + constructor. + + Note that a QApplication must have been constructed before sockets + can be used. +*/ + +QSocket::QSocket( QObject *parent, const char *name ) + : QObject( parent, name ) +{ + d = new QSocketPrivate; + setSocketDevice( 0 ); + setFlags( IO_Direct ); + resetStatus(); +} + + +/*! + Destroys the socket. Closes the connection if necessary. + + \sa close() +*/ + +QSocket::~QSocket() +{ +#if defined(QSOCKET_DEBUG) + qDebug( "QSocket (%s): Destroy", name() ); +#endif + if ( state() != Idle ) + close(); + Q_ASSERT( d != 0 ); + delete d; +} + + +/*! + Returns a pointer to the internal socket device. + + There is normally no need to manipulate the socket device directly + since this class does the necessary setup for most applications. +*/ + +QSocketDevice *QSocket::socketDevice() +{ + return d->socket; +} + +/*! + Sets the internal socket device to \a device. Passing a \a device + of 0 will cause the internal socket device to be used. Any + existing connection will be disconnected before using the new \a + device. + + The new device should not be connected before being associated + with a QSocket; after setting the socket call connectToHost() to + make the connection. + + This function is useful if you need to subclass QSocketDevice and + want to use the QSocket API, for example, to implement Unix domain + sockets. +*/ + +void QSocket::setSocketDevice( QSocketDevice *device ) +{ + if ( state() != Idle ) + close(); + d->setSocketDevice( this, device ); +} + +/*! + \enum QSocket::State + + This enum defines the connection states: + + \value Idle if there is no connection + \value HostLookup during a DNS lookup + \value Connecting during TCP connection establishment + \value Connected when there is an operational connection + \value Closing if the socket is closing down, but is not yet closed. +*/ + +/*! + Returns the current state of the socket connection. + + \sa QSocket::State +*/ + +QSocket::State QSocket::state() const +{ + return d->state; +} + + +#ifndef QT_NO_DNS + +/*! + Attempts to make a connection to \a host on the specified \a port + and return immediately. + + Any connection or pending connection is closed immediately, and + QSocket goes into the \c HostLookup state. When the lookup + succeeds, it emits hostFound(), starts a TCP connection and goes + into the \c Connecting state. Finally, when the connection + succeeds, it emits connected() and goes into the \c Connected + state. If there is an error at any point, it emits error(). + + \a host may be an IP address in string form, or it may be a DNS + name. QSocket will do a normal DNS lookup if required. Note that + \a port is in native byte order, unlike some other libraries. + + \sa state() +*/ + +void QSocket::connectToHost( const QString &host, Q_UINT16 port ) +{ +#if defined(QSOCKET_DEBUG) + qDebug( "QSocket (%s)::connectToHost: host %s, port %d", + name(), host.ascii(), port ); +#endif + setSocketIntern( -1 ); + d->state = HostLookup; + d->host = host; + d->port = port; + d->dns4 = new QDns( host, QDns::A ); + d->dns6 = new QDns( host, QDns::Aaaa ); + + // try if the address is already available (for faster connecting...) + tryConnecting(); + if ( d->state == HostLookup ) { + connect( d->dns4, SIGNAL(resultsReady()), + this, SLOT(tryConnecting()) ); + connect( d->dns6, SIGNAL(resultsReady()), + this, SLOT(tryConnecting()) ); + } +} + +#endif + + +/*! + This private slots continues the connection process where + connectToHost() leaves off. +*/ + +void QSocket::tryConnecting() +{ +#if defined(QSOCKET_DEBUG) + qDebug( "QSocket (%s)::tryConnecting()", name() ); +#endif + // ### this ifdef isn't correct - addresses() also does /etc/hosts and + // numeric-address-as-string handling. +#ifndef QT_NO_DNS + + if ( d->dns4 ) { + d->l4 = d->dns4->addresses(); + if ( !d->l4.isEmpty() || !d->dns4->isWorking() ) { +#if defined(QSOCKET_DEBUG) + qDebug( "QSocket (%s)::tryConnecting: host %s, port %d: " + "%d IPv4 addresses", + name(), d->host.ascii(), d->port, d->l4.count() ); +#endif + delete d->dns4; + d->dns4 = 0; + } + } + + if ( d->dns6 ) { + d->l6 = d->dns6->addresses(); + if ( !d->l6.isEmpty() || !d->dns6->isWorking() ) { +#if defined(QSOCKET_DEBUG) + qDebug( "QSocket (%s)::tryConnecting: host %s, port %d: " + "%d IPv6 addresses", + name(), d->host.ascii(), d->port, d->l6.count() ); +#endif + delete d->dns6; + d->dns6 = 0; + } + } + + if ( d->state == HostLookup ) { + if ( d->l4.isEmpty() && d->l6.isEmpty() && + !d->dns4 && !d->dns6 ) { + // no results and we're not still looking: give up + d->state = Idle; + emit error( ErrHostNotFound ); + return; + } + if ( d->l4.isEmpty() && d->l6.isEmpty() ) { + // no results (yet): try again later + return; + } + + // we've found something. press on with that. if we later find + // more, fine. + emit hostFound(); + d->state = Connecting; + } + + if ( d->state == Connecting ) { + d->addresses += d->l4; + d->addresses += d->l6; + d->l4.clear(); + d->l6.clear(); + + // try one address at a time, falling back to the next one if + // there is a connection failure. (should also support a timeout, + // or do multiple TCP-level connects at a time, with staggered + // starts to avoid bandwidth waste and cause fewer + // "connect-and-abort" errors. but that later.) + bool stuck = TRUE; + while( stuck ) { + stuck = FALSE; + if ( d->socket && + d->socket->connect( d->addr, d->port ) == FALSE ) { + if ( d->socket->error() == QSocketDevice::NoError ) { + if ( d->wsn ) + d->wsn->setEnabled( TRUE ); + return; // not serious, try again later + } + +#if defined(QSOCKET_DEBUG) + qDebug( "QSocket (%s)::tryConnecting: " + "Gave up on IP address %s", + name(), d->socket->peerAddress().toString().ascii() ); +#endif + delete d->wsn; + d->wsn = 0; + delete d->rsn; + d->rsn = 0; + delete d->socket; + d->socket = 0; + + if(d->addresses.isEmpty()) { + emit error( ErrConnectionRefused ); + return; + } + } + // if the host has more addresses, try another some. + if ( d->socket == 0 && !d->addresses.isEmpty() ) { + d->addr = *d->addresses.begin(); + d->addresses.remove( d->addresses.begin() ); + d->setSocketDevice( this, 0 ); + stuck = TRUE; +#if defined(QSOCKET_DEBUG) + qDebug( "QSocket (%s)::tryConnecting: Trying IP address %s", + name(), d->addr.toString().ascii() ); +#endif + } + }; + + // The socket write notifier will fire when the connection succeeds + if ( d->wsn ) + d->wsn->setEnabled( TRUE ); + } +#endif +} + +/*! + \enum QSocket::Error + + This enum specifies the possible errors: + \value ErrConnectionRefused if the connection was refused + \value ErrHostNotFound if the host was not found + \value ErrSocketRead if a read from the socket failed +*/ + +/*! + \fn void QSocket::error( int ) + + This signal is emitted after an error occurred. The parameter is + the \l Error value. +*/ + +/*! + \fn void QSocket::hostFound() + + This signal is emitted after connectToHost() has been called and + the host lookup has succeeded. + + \sa connected() +*/ + + +/*! + \fn void QSocket::connected() + + This signal is emitted after connectToHost() has been called and a + connection has been successfully established. + + \sa connectToHost(), connectionClosed() +*/ + + +/*! + \fn void QSocket::connectionClosed() + + This signal is emitted when the other end has closed the + connection. The read buffers may contain buffered input data which + you can read after the connection was closed. + + \sa connectToHost(), close() +*/ + + +/*! + \fn void QSocket::delayedCloseFinished() + + This signal is emitted when a delayed close is finished. + + If you call close() and there is buffered output data to be + written, QSocket goes into the \c QSocket::Closing state and + returns immediately. It will then keep writing to the socket until + all the data has been written. Then, the delayedCloseFinished() + signal is emitted. + + \sa close() +*/ + + +/*! + \fn void QSocket::readyRead() + + This signal is emitted every time there is new incoming data. + + Bear in mind that new incoming data is only reported once; if you do not + read all the data, this class buffers the data and you can read it later, + but no signal is emitted unless new data arrives. A good practice is to + read all data in the slot connected to this signal unless you are sure that + you need to receive more data to be able to process it. + + \sa readBlock(), readLine(), bytesAvailable() +*/ + + +/*! + \fn void QSocket::bytesWritten( int nbytes ) + + This signal is emitted when data has been written to the network. + The \a nbytes parameter specifies how many bytes were written. + + The bytesToWrite() function is often used in the same context; it + indicates how many buffered bytes there are left to write. + + \sa writeBlock(), bytesToWrite() +*/ + + +/*! + Opens the socket using the specified QIODevice file mode \a m. + This function is called automatically when needed and you should + not call it yourself. + + \sa close() +*/ + +bool QSocket::open( int m ) +{ + if ( isOpen() ) { +#if defined(QT_CHECK_STATE) + qWarning( "QSocket::open: Already open" ); +#endif + return FALSE; + } + QIODevice::setMode( m & IO_ReadWrite ); + setState( IO_Open ); + return TRUE; +} + + +/*! + Closes the socket. + + The read buffer is cleared. + + If the output buffer is empty, the state is set to \c + QSocket::Idle and the connection is terminated immediately. If the + output buffer still contains data to be written, QSocket goes into + the \c QSocket::Closing state and the rest of the data will be + written. When all of the outgoing data have been written, the + state is set to \c QSocket::Idle and the connection is terminated. + At this point, the delayedCloseFinished() signal is emitted. + + If you don't want that the data of the output buffer is written, call + clearPendingData() before you call close(). + + \sa state(), bytesToWrite() clearPendingData() +*/ + +void QSocket::close() +{ + if ( !isOpen() || d->state == Idle ) // already closed + return; + if ( d->state == Closing ) + return; + if ( !d->rsn || !d->wsn ) + return; +#if defined(QSOCKET_DEBUG) + qDebug( "QSocket (%s): close socket", name() ); +#endif + if ( d->socket && d->wsize ) { // there's data to be written + d->state = Closing; + if ( d->rsn ) + d->rsn->setEnabled( FALSE ); + if ( d->wsn ) + d->wsn->setEnabled( TRUE ); + d->rba.clear(); // clear incoming data + return; + } + setFlags( IO_Sequential ); + resetStatus(); + setState( 0 ); + d->close(); + d->state = Idle; +} + + +/*! + This function consumes \a nbytes bytes of data from the write + buffer. +*/ + +bool QSocket::consumeWriteBuf( Q_ULONG nbytes ) +{ + if ( nbytes <= 0 || nbytes > d->wsize ) + return FALSE; +#if defined(QSOCKET_DEBUG) + qDebug( "QSocket (%s): skipWriteBuf %d bytes", name(), (int)nbytes ); +#endif + d->wsize -= nbytes; + for ( ;; ) { + QByteArray *a = d->wba.first(); + if ( d->windex + nbytes >= a->size() ) { + nbytes -= a->size() - d->windex; + d->wba.remove(); + d->windex = 0; + if ( nbytes == 0 ) + break; + } else { + d->windex += nbytes; + break; + } + } + return TRUE; +} + + + +/*! + Implementation of the abstract virtual QIODevice::flush() function. +*/ + +void QSocket::flush() +{ + if ( !d->socket ) + return; + bool osBufferFull = FALSE; + int consumed = 0; + while ( !osBufferFull && d->state >= Connecting && d->wsize > 0 ) { +#if defined(QSOCKET_DEBUG) + qDebug( "QSocket (%s): flush: Write data to the socket", name() ); +#endif + QByteArray *a = d->wba.first(); + int nwritten; + int i = 0; + if ( (int)a->size() - d->windex < 1460 ) { + // Concatenate many smaller blocks. the first may be + // partial, but each subsequent block is copied entirely + // or not at all. the sizes here are picked so that we + // generally won't trigger nagle's algorithm in the tcp + // implementation: we concatenate if we'd otherwise send + // less than PMTU bytes (we assume PMTU is 1460 bytes), + // and concatenate up to the largest payload TCP/IP can + // carry. with these precautions, nagle's algorithm + // should apply only when really appropriate. + QByteArray out( 65536 ); + int j = d->windex; + int s = a->size() - j; + while ( a && i+s < (int)out.size() ) { + memcpy( out.data()+i, a->data()+j, s ); + j = 0; + i += s; + a = d->wba.next(); + s = a ? a->size() : 0; + } + nwritten = d->socket->writeBlock( out.data(), i ); + if ( d->wsn ) + d->wsn->setEnabled( FALSE ); // the QSocketNotifier documentation says so + } else { + // Big block, write it immediately + i = a->size() - d->windex; + nwritten = d->socket->writeBlock( a->data() + d->windex, i ); + if ( d->wsn ) + d->wsn->setEnabled( FALSE ); // the QSocketNotifier documentation says so + } + if ( nwritten > 0 ) { + if ( consumeWriteBuf( nwritten ) ) + consumed += nwritten; + } + if ( nwritten < i ) + osBufferFull = TRUE; + } + if ( consumed > 0 ) { +#if defined(QSOCKET_DEBUG) + qDebug( "QSocket (%s): flush: wrote %d bytes, %d left", + name(), consumed, (int)d->wsize ); +#endif + emit bytesWritten( consumed ); + } + if ( d->state == Closing && d->wsize == 0 ) { +#if defined(QSOCKET_DEBUG) + qDebug( "QSocket (%s): flush: Delayed close done. Terminating.", + name() ); +#endif + setFlags( IO_Sequential ); + resetStatus(); + setState( 0 ); + d->close(); + d->state = Idle; + emit delayedCloseFinished(); + return; + } + if ( !d->socket->isOpen() ) { + d->connectionClosed(); + emit connectionClosed(); + return; + } + if ( d->wsn ) + d->wsn->setEnabled( d->wsize > 0 ); // write if there's data +} + + +/*! + Returns the number of incoming bytes that can be read right now + (like bytesAvailable()). +*/ + +QIODevice::Offset QSocket::size() const +{ + return (Offset)bytesAvailable(); +} + + +/*! + Returns the current read index. Since QSocket is a sequential + device, the current read index is always zero. +*/ + +QIODevice::Offset QSocket::at() const +{ + return 0; +} + + +/*! + \overload + + Moves the read index forward to \a index and returns TRUE if the + operation was successful; otherwise returns FALSE. Moving the + index forward means skipping incoming data. +*/ + +bool QSocket::at( Offset index ) +{ + if ( index > d->rba.size() ) + return FALSE; + d->rba.consumeBytes( (Q_ULONG)index, 0 ); // throw away data 0..index-1 + // After we read data from our internal buffer, if we use the + // setReadBufferSize() to limit our buffer, we might now be able to + // read more data in our buffer. So enable the read socket notifier, + // but do this only if we are not in a slot connected to the + // readyRead() signal since this might cause a bad recursive behavior. + // We can test for this condition by looking at the + // sn_read_alreadyCalled flag. + if ( d->rsn && QSocketPrivate::sn_read_alreadyCalled.findRef(this) == -1 ) + d->rsn->setEnabled( TRUE ); + return TRUE; +} + + +/*! + Returns TRUE if there is no more data to read; otherwise returns FALSE. +*/ + +bool QSocket::atEnd() const +{ + if ( d->socket == 0 ) + return TRUE; + QSocket * that = (QSocket *)this; + if ( that->d->socket->bytesAvailable() ) // a little slow, perhaps... + that->sn_read(); + return that->d->rba.size() == 0; +} + + +/*! + Returns the number of incoming bytes that can be read, i.e. the + size of the input buffer. Equivalent to size(). + + This function can trigger the readyRead() signal, if more data has + arrived on the socket. + + \sa bytesToWrite() +*/ + +Q_ULONG QSocket::bytesAvailable() const +{ + if ( d->socket == 0 ) + return 0; + QSocket * that = (QSocket *)this; + if ( that->d->socket->bytesAvailable() ) // a little slow, perhaps... + (void)that->sn_read(); + return that->d->rba.size(); +} + + +/*! + Wait up to \a msecs milliseconds for more data to be available. + + If \a msecs is -1 the call will block indefinitely. + + Returns the number of bytes available. + + If \a timeout is non-null and no error occurred (i.e. it does not + return -1): this function sets \a *timeout to TRUE, if the reason + for returning was that the timeout was reached; otherwise it sets + \a *timeout to FALSE. This is useful to find out if the peer + closed the connection. + + \warning This is a blocking call and should be avoided in event + driven applications. + + \sa bytesAvailable() +*/ + +Q_ULONG QSocket::waitForMore( int msecs, bool *timeout ) const +{ + if ( d->socket == 0 ) + return 0; + QSocket * that = (QSocket *)this; + if ( that->d->socket->waitForMore( msecs, timeout ) > 0 ) + (void)that->sn_read( TRUE ); + return that->d->rba.size(); +} + +/*! \overload +*/ + +Q_ULONG QSocket::waitForMore( int msecs ) const +{ + return waitForMore( msecs, 0 ); +} + +/*! + Returns the number of bytes that are waiting to be written, i.e. + the size of the output buffer. + + \sa bytesAvailable() clearPendingData() +*/ + +Q_ULONG QSocket::bytesToWrite() const +{ + return d->wsize; +} + +/*! + Deletes the data that is waiting to be written. This is useful if you want + to close the socket without waiting for all the data to be written. + + \sa bytesToWrite() close() delayedCloseFinished() +*/ + +void QSocket::clearPendingData() +{ + d->wba.clear(); + d->windex = d->wsize = 0; +} + +/*! + Reads \a maxlen bytes from the socket into \a data and returns the + number of bytes read. Returns -1 if an error occurred. +*/ + +Q_LONG QSocket::readBlock( char *data, Q_ULONG maxlen ) +{ + if ( data == 0 && maxlen != 0 ) { +#if defined(QT_CHECK_NULL) + qWarning( "QSocket::readBlock: Null pointer error" ); +#endif + return -1; + } + if ( !isOpen() ) { +#if defined(QT_CHECK_STATE) + qWarning( "QSocket::readBlock: Socket is not open" ); +#endif + return -1; + } + if ( maxlen >= d->rba.size() ) + maxlen = d->rba.size(); +#if defined(QSOCKET_DEBUG) + qDebug( "QSocket (%s): readBlock %d bytes", name(), (int)maxlen ); +#endif + d->rba.consumeBytes( maxlen, data ); + // After we read data from our internal buffer, if we use the + // setReadBufferSize() to limit our buffer, we might now be able to + // read more data in our buffer. So enable the read socket notifier, + // but do this only if we are not in a slot connected to the + // readyRead() signal since this might cause a bad recursive behavior. + // We can test for this condition by looking at the + // sn_read_alreadyCalled flag. + if ( d->rsn && QSocketPrivate::sn_read_alreadyCalled.findRef(this) == -1 ) + d->rsn->setEnabled( TRUE ); + return maxlen; +} + + +/*! + Writes \a len bytes to the socket from \a data and returns the + number of bytes written. Returns -1 if an error occurred. +*/ + +Q_LONG QSocket::writeBlock( const char *data, Q_ULONG len ) +{ +#if defined(QT_CHECK_NULL) + if ( data == 0 && len != 0 ) { + qWarning( "QSocket::writeBlock: Null pointer error" ); + } +#endif +#if defined(QT_CHECK_STATE) + if ( !isOpen() ) { + qWarning( "QSocket::writeBlock: Socket is not open" ); + return -1; + } +#endif +#if defined(QT_CHECK_STATE) + if ( d->state == Closing ) { + qWarning( "QSocket::writeBlock: Cannot write, socket is closing" ); + } +#endif + if ( len == 0 || d->state == Closing || d->state == Idle ) + return 0; + QByteArray *a = d->wba.last(); + + // next bit is sensitive. if we're writing really small chunks, + // try to buffer up since system calls are expensive, and nagle's + // algorithm is even more expensive. but if anything even + // remotely large is being written, try to issue a write at once. + + bool writeNow = ( d->wsize + len >= 1400 || len > 512 ); + + if ( a && a->size() + len < 128 ) { + // small buffer, resize + int i = a->size(); + a->resize( i+len ); + memcpy( a->data()+i, data, len ); + } else { + // append new buffer + a = new QByteArray( len ); + memcpy( a->data(), data, len ); + d->wba.append( a ); + } + d->wsize += len; + if ( writeNow ) + flush(); + else if ( d->wsn ) + d->wsn->setEnabled( TRUE ); +#if defined(QSOCKET_DEBUG) + qDebug( "QSocket (%s): writeBlock %d bytes", name(), (int)len ); +#endif + return len; +} + + +/*! + Reads a single byte/character from the internal read buffer. + Returns the byte/character read, or -1 if there is nothing to be + read. + + \sa bytesAvailable(), putch() +*/ + +int QSocket::getch() +{ + if ( isOpen() && d->rba.size() > 0 ) { + uchar c; + d->rba.consumeBytes( 1, (char*)&c ); + // After we read data from our internal buffer, if we use the + // setReadBufferSize() to limit our buffer, we might now be able to + // read more data in our buffer. So enable the read socket notifier, + // but do this only if we are not in a slot connected to the + // readyRead() signal since this might cause a bad recursive behavior. + // We can test for this condition by looking at the + // sn_read_alreadyCalled flag. + if ( d->rsn && QSocketPrivate::sn_read_alreadyCalled.findRef(this) == -1 ) + d->rsn->setEnabled( TRUE ); + return c; + } + return -1; +} + + +/*! + Writes the character \a ch to the output buffer. + + Returns \a ch, or -1 if an error occurred. + + \sa getch() +*/ + +int QSocket::putch( int ch ) +{ + char buf[2]; + buf[0] = ch; + return writeBlock(buf, 1) == 1 ? ch : -1; +} + + +/*! + This implementation of the virtual function QIODevice::ungetch() + prepends the character \a ch to the read buffer so that the next + read returns this character as the first character of the output. +*/ + +int QSocket::ungetch( int ch ) +{ +#if defined(QT_CHECK_STATE) + if ( !isOpen() ) { + qWarning( "QSocket::ungetch: Socket not open" ); + return -1; + } +#endif + return d->rba.ungetch( ch ); +} + + +/*! + Returns TRUE if it's possible to read an entire line of text from + this socket at this time; otherwise returns FALSE. + + Note that if the peer closes the connection unexpectedly, this + function returns FALSE. This means that loops such as this won't + work: + + \code + while( !socket->canReadLine() ) // WRONG + ; + \endcode + + \sa readLine() +*/ + +bool QSocket::canReadLine() const +{ + if ( ((QSocket*)this)->d->rba.scanNewline( 0 ) ) + return TRUE; + return ( bytesAvailable() > 0 && + ((QSocket*)this)->d->rba.scanNewline( 0 ) ); +} + +/*! + \reimp + \internal + So that it's not hidden by our other readLine(). +*/ +Q_LONG QSocket::readLine( char *data, Q_ULONG maxlen ) +{ + return QIODevice::readLine(data,maxlen); +} + +/*! + Returns a line of text including a terminating newline character + (\n). Returns "" if canReadLine() returns FALSE. + + \sa canReadLine() +*/ + +QString QSocket::readLine() +{ + QByteArray a(256); + bool nl = d->rba.scanNewline( &a ); + QString s; + if ( nl ) { + at( a.size() ); // skips the data read + s = QString( a ); + } + return s; +} + +/*! + \internal + Internal slot for handling socket read notifications. + + This function has can usually only be entered once (i.e. no + recursive calls). If the argument \a force is TRUE, the function + is executed, but no readyRead() signals are emitted. This + behaviour is useful for the waitForMore() function, so that it is + possible to call waitForMore() in a slot connected to the + readyRead() signal. +*/ + +void QSocket::sn_read( bool force ) +{ + Q_LONG maxToRead = 0; + if ( d->readBufferSize > 0 ) { + maxToRead = d->readBufferSize - d->rba.size(); + if ( maxToRead <= 0 ) { + if ( d->rsn ) + d->rsn->setEnabled( FALSE ); + return; + } + } + + // Use QSocketPrivate::sn_read_alreadyCalled to avoid recursive calls of + // sn_read() (and as a result avoid emitting the readyRead() signal in a + // slot for readyRead(), if you use bytesAvailable()). + if ( !force && QSocketPrivate::sn_read_alreadyCalled.findRef(this) != -1 ) + return; + QSocketPrivate::sn_read_alreadyCalled.append( this ); + + char buf[4096]; + Q_LONG nbytes = d->socket->bytesAvailable(); + Q_LONG nread; + QByteArray *a = 0; + + if ( state() == Connecting ) { + if ( nbytes > 0 ) { + tryConnection(); + } else { + // nothing to do, nothing to care about + QSocketPrivate::sn_read_alreadyCalled.removeRef( this ); + return; + } + } + if ( state() == Idle ) { + QSocketPrivate::sn_read_alreadyCalled.removeRef( this ); + return; + } + + if ( nbytes <= 0 ) { // connection closed? + // On Windows this may happen when the connection is still open. + // This happens when the system is heavily loaded and we have + // read all the data on the socket before a new WSAAsyncSelect + // event is processed. A new read operation would then block. + // This code is also useful when QSocket is used without an + // event loop. + nread = d->socket->readBlock( buf, maxToRead ? QMIN((Q_LONG)sizeof(buf),maxToRead) : sizeof(buf) ); + if ( nread == 0 ) { // really closed + if ( !d->socket->isOpen() ) { +#if defined(QSOCKET_DEBUG) + qDebug( "QSocket (%s): sn_read: Connection closed", name() ); +#endif + d->connectionClosed(); + emit connectionClosed(); + } + QSocketPrivate::sn_read_alreadyCalled.removeRef( this ); + return; + } else { + if ( nread < 0 ) { + if ( d->socket->error() == QSocketDevice::NoError ) { + // all is fine + QSocketPrivate::sn_read_alreadyCalled.removeRef( this ); + return; + } +#if defined(QSOCKET_DEBUG) + qWarning( "QSocket::sn_read (%s): Close error", name() ); +#endif + if ( d->rsn ) + d->rsn->setEnabled( FALSE ); + emit error( ErrSocketRead ); + QSocketPrivate::sn_read_alreadyCalled.removeRef( this ); + return; + } + a = new QByteArray( nread ); + memcpy( a->data(), buf, nread ); + } + + } else { // data to be read +#if defined(QSOCKET_DEBUG) + qDebug( "QSocket (%s): sn_read: %ld incoming bytes", name(), nbytes ); +#endif + if ( nbytes > (int)sizeof(buf) ) { + // big + a = new QByteArray( nbytes ); + nread = d->socket->readBlock( a->data(), maxToRead ? QMIN(nbytes,maxToRead) : nbytes ); + } else { + a = 0; + nread = d->socket->readBlock( buf, maxToRead ? QMIN((Q_LONG)sizeof(buf),maxToRead) : sizeof(buf) ); + if ( nread > 0 ) { + // ##### could setRawData + a = new QByteArray( nread ); + memcpy( a->data(), buf, nread ); + } + } + if ( nread == 0 ) { +#if defined(QSOCKET_DEBUG) + qDebug( "QSocket (%s): sn_read: Connection closed", name() ); +#endif + // ### we should rather ask the socket device if it is closed + d->connectionClosed(); + emit connectionClosed(); + QSocketPrivate::sn_read_alreadyCalled.removeRef( this ); + delete a; + return; + } else if ( nread < 0 ) { + delete a; + + if ( d->socket->error() == QSocketDevice::NoError ) { + // all is fine + QSocketPrivate::sn_read_alreadyCalled.removeRef( this ); + return; + } +#if defined(QT_CHECK_RANGE) + qWarning( "QSocket::sn_read: Read error" ); +#endif + if ( d->rsn ) + d->rsn->setEnabled( FALSE ); + emit error( ErrSocketRead ); + QSocketPrivate::sn_read_alreadyCalled.removeRef( this ); + return; + } + if ( nread != (int)a->size() ) { // unexpected +#if defined(CHECK_RANGE) && !defined(Q_OS_WIN32) + qWarning( "QSocket::sn_read: Unexpected short read" ); +#endif + a->resize( nread ); + } + } + d->rba.append( a ); + if ( !force ) { + if ( d->rsn ) + d->rsn->setEnabled( FALSE ); + emit readyRead(); + if ( d->rsn ) + d->rsn->setEnabled( TRUE ); + } + + QSocketPrivate::sn_read_alreadyCalled.removeRef( this ); +} + + +/*! + \internal + Internal slot for handling socket write notifications. +*/ + +void QSocket::sn_write() +{ + if ( d->state == Connecting ) // connection established? + tryConnection(); + flush(); +} + +void QSocket::emitErrorConnectionRefused() +{ + emit error( ErrConnectionRefused ); +} + +void QSocket::tryConnection() +{ + if ( d->socket->connect( d->addr, d->port ) ) { + d->state = Connected; +#if defined(QSOCKET_DEBUG) + qDebug( "QSocket (%s): sn_write: Got connection to %s", + name(), peerName().ascii() ); +#endif + if ( d->rsn ) + d->rsn->setEnabled( TRUE ); + emit connected(); + } else { + d->state = Idle; + QTimer::singleShot( 0, this, SLOT(emitErrorConnectionRefused()) ); + return; + } +} + + +/*! + Returns the socket number, or -1 if there is no socket at the moment. +*/ + +int QSocket::socket() const +{ + if ( d->socket == 0 ) + return -1; + return d->socket->socket(); +} + +/*! + Sets the socket to use \a socket and the state() to \c Connected. + The socket must already be connected. + + This allows us to use the QSocket class as a wrapper for other + socket types (e.g. Unix Domain Sockets). +*/ + +void QSocket::setSocket( int socket ) +{ + setSocketIntern( socket ); + d->state = Connection; + d->rsn->setEnabled( TRUE ); +} + + +/*! + Sets the socket to \a socket. This is used by both setSocket() and + connectToHost() and can also be used on unconnected sockets. +*/ + +void QSocket::setSocketIntern( int socket ) +{ + if ( state() != Idle ) { + clearPendingData(); + close(); + } + Q_ULONG oldBufferSize = d ? d->readBufferSize : 0; + delete d; + + d = new QSocketPrivate; + if (oldBufferSize) + d->readBufferSize = oldBufferSize; + if ( socket >= 0 ) { + QSocketDevice *sd = new QSocketDevice( socket, QSocketDevice::Stream ); + sd->setBlocking( FALSE ); + sd->setAddressReusable( TRUE ); + d->setSocketDevice( this, sd ); + } + d->state = Idle; + + // Initialize the IO device flags + setFlags( IO_Direct ); + resetStatus(); + open( IO_ReadWrite ); + + // hm... this is not very nice. + d->host = QString::null; + d->port = 0; +#ifndef QT_NO_DNS + delete d->dns4; + d->dns4 = 0; + delete d->dns6; + d->dns6 = 0; +#endif +} + + +/*! + Returns the host port number of this socket, in native byte order. +*/ + +Q_UINT16 QSocket::port() const +{ + if ( d->socket == 0 ) + return 0; + return d->socket->port(); +} + + +/*! + Returns the peer's host port number, normally as specified to the + connectToHost() function. If none has been set, this function + returns 0. + + Note that Qt always uses native byte order, i.e. 67 is 67 in Qt; + there is no need to call htons(). +*/ + +Q_UINT16 QSocket::peerPort() const +{ + if ( d->socket == 0 ) + return 0; + return d->socket->peerPort(); +} + + +/*! + Returns the host address of this socket. (This is normally the + main IP address of the host, but can be e.g. 127.0.0.1 for + connections to localhost.) +*/ + +QHostAddress QSocket::address() const +{ + if ( d->socket == 0 ) { + QHostAddress tmp; + return tmp; + } + return d->socket->address(); +} + + +/*! + Returns the address of the connected peer if the socket is in + Connected state; otherwise an empty QHostAddress is returned. +*/ + +QHostAddress QSocket::peerAddress() const +{ + if ( d->socket == 0 ) { + QHostAddress tmp; + return tmp; + } + return d->socket->peerAddress(); +} + + +/*! + Returns the host name as specified to the connectToHost() + function. An empty string is returned if none has been set. +*/ + +QString QSocket::peerName() const +{ + return d->host; +} + +/*! + Sets the size of the QSocket's internal read buffer to \a bufSize. + + Usually QSocket reads all data that is available from the operating + system's socket. If the buffer size is limited to a certain size, this + means that the QSocket class doesn't buffer more than this size of data. + + If the size of the read buffer is 0, the read buffer is unlimited and all + incoming data is buffered. This is the default. + + If you read the data in the readyRead() signal, you shouldn't use this + option since it might slow down your program unnecessary. This option is + useful if you only need to read the data at certain points in time, like in + a realtime streaming application. + + \sa readBufferSize() +*/ + +void QSocket::setReadBufferSize( Q_ULONG bufSize ) +{ + d->readBufferSize = bufSize; +} + +/*! + Returns the size of the read buffer. + + \sa setReadBufferSize() +*/ + +Q_ULONG QSocket::readBufferSize() const +{ + return d->readBufferSize; +} + +#endif //QT_NO_NETWORK |