--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/corelib/io/qbuffer.cpp	Mon Jan 11 14:00:40 2010 +0000
@@ -0,0 +1,475 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** All rights reserved.
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** This file is part of the QtCore module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** No Commercial Usage
+** This file contains pre-release code and may not be distributed.
+** You may use this file in accordance with the terms and conditions
+** contained in the Technology Preview License Agreement accompanying
+** this package.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, Nokia gives you certain additional
+** rights.  These rights are described in the Nokia Qt LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+** If you have questions regarding the use of this file, please contact
+** Nokia at qt-info@nokia.com.
+**
+**
+**
+**
+**
+**
+**
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include "qbuffer.h"
+#include "private/qiodevice_p.h"
+
+QT_BEGIN_NAMESPACE
+
+/** QBufferPrivate **/
+class QBufferPrivate : public QIODevicePrivate
+{
+    Q_DECLARE_PUBLIC(QBuffer)
+
+public:
+    QBufferPrivate()
+    : buf(0)
+#ifndef QT_NO_QOBJECT
+        , writtenSinceLastEmit(0), signalConnectionCount(0), signalsEmitted(false)
+#endif
+    { }
+    ~QBufferPrivate() { }
+
+    QByteArray *buf;
+    QByteArray defaultBuf;
+    int ioIndex;
+
+#ifndef QT_NO_QOBJECT
+    // private slots
+    void _q_emitSignals();
+
+    qint64 writtenSinceLastEmit;
+    int signalConnectionCount;
+    bool signalsEmitted;
+#endif
+};
+
+#ifndef QT_NO_QOBJECT
+void QBufferPrivate::_q_emitSignals()
+{
+    Q_Q(QBuffer);
+    emit q->bytesWritten(writtenSinceLastEmit);
+    writtenSinceLastEmit = 0;
+    emit q->readyRead();
+    signalsEmitted = false;
+}
+#endif
+
+/*!
+    \class QBuffer
+    \reentrant
+    \brief The QBuffer class provides a QIODevice interface for a QByteArray.
+
+    \ingroup io
+
+    QBuffer allows you to access a QByteArray using the QIODevice
+    interface. The QByteArray is treated just as a standard random-accessed
+    file. Example:
+
+    \snippet doc/src/snippets/buffer/buffer.cpp 0
+
+    By default, an internal QByteArray buffer is created for you when
+    you create a QBuffer. You can access this buffer directly by
+    calling buffer(). You can also use QBuffer with an existing
+    QByteArray by calling setBuffer(), or by passing your array to
+    QBuffer's constructor.
+
+    Call open() to open the buffer. Then call write() or
+    putChar() to write to the buffer, and read(), readLine(),
+    readAll(), or getChar() to read from it. size() returns the
+    current size of the buffer, and you can seek to arbitrary
+    positions in the buffer by calling seek(). When you are done with
+    accessing the buffer, call close().
+
+    The following code snippet shows how to write data to a
+    QByteArray using QDataStream and QBuffer:
+
+    \snippet doc/src/snippets/buffer/buffer.cpp 1
+
+    Effectively, we convert the application's QPalette into a byte
+    array. Here's how to read the data from the QByteArray:
+
+    \snippet doc/src/snippets/buffer/buffer.cpp 2
+
+    QTextStream and QDataStream also provide convenience constructors
+    that take a QByteArray and that create a QBuffer behind the
+    scenes.
+
+    QBuffer emits readyRead() when new data has arrived in the
+    buffer. By connecting to this signal, you can use QBuffer to
+    store temporary data before processing it. For example, you can
+    pass the buffer to QFtp when downloading a file from an FTP
+    server. Whenever a new payload of data has been downloaded,
+    readyRead() is emitted, and you can process the data that just
+    arrived. QBuffer also emits bytesWritten() every time new data
+    has been written to the buffer.
+
+    \sa QFile, QDataStream, QTextStream, QByteArray
+*/
+
+#ifdef QT_NO_QOBJECT
+QBuffer::QBuffer()
+    : QIODevice(*new QBufferPrivate)
+{
+    Q_D(QBuffer);
+    d->buf = &d->defaultBuf;
+    d->ioIndex = 0;
+}
+QBuffer::QBuffer(QByteArray *buf)
+    : QIODevice(*new QBufferPrivate)
+{
+    Q_D(QBuffer);
+    d->buf = buf ? buf : &d->defaultBuf;
+    d->ioIndex = 0;
+    d->defaultBuf.clear();
+}
+#else
+/*!
+    Constructs an empty buffer with the given \a parent. You can call
+    setData() to fill the buffer with data, or you can open it in
+    write mode and use write().
+
+    \sa open()
+*/
+QBuffer::QBuffer(QObject *parent)
+    : QIODevice(*new QBufferPrivate, parent)
+{
+    Q_D(QBuffer);
+    d->buf = &d->defaultBuf;
+    d->ioIndex = 0;
+}
+
+/*!
+    Constructs a QBuffer that uses the QByteArray pointed to by \a
+    byteArray as its internal buffer, and with the given \a parent.
+    The caller is responsible for ensuring that \a byteArray remains
+    valid until the QBuffer is destroyed, or until setBuffer() is
+    called to change the buffer. QBuffer doesn't take ownership of
+    the QByteArray.
+
+    If you open the buffer in write-only mode or read-write mode and
+    write something into the QBuffer, \a byteArray will be modified.
+
+    Example:
+
+    \snippet doc/src/snippets/buffer/buffer.cpp 3
+
+    \sa open(), setBuffer(), setData()
+*/
+QBuffer::QBuffer(QByteArray *byteArray, QObject *parent)
+    : QIODevice(*new QBufferPrivate, parent)
+{
+    Q_D(QBuffer);
+    d->buf = byteArray ? byteArray : &d->defaultBuf;
+    d->defaultBuf.clear();
+    d->ioIndex = 0;
+}
+#endif
+
+/*!
+    Destroys the buffer.
+*/
+
+QBuffer::~QBuffer()
+{
+}
+
+/*!
+    Makes QBuffer uses the QByteArray pointed to by \a
+    byteArray as its internal buffer. The caller is responsible for
+    ensuring that \a byteArray remains valid until the QBuffer is
+    destroyed, or until setBuffer() is called to change the buffer.
+    QBuffer doesn't take ownership of the QByteArray.
+
+    Does nothing if isOpen() is true.
+
+    If you open the buffer in write-only mode or read-write mode and
+    write something into the QBuffer, \a byteArray will be modified.
+
+    Example:
+
+    \snippet doc/src/snippets/buffer/buffer.cpp 4
+
+    If \a byteArray is 0, the buffer creates its own internal
+    QByteArray to work on. This byte array is initially empty.
+
+    \sa buffer(), setData(), open()
+*/
+
+void QBuffer::setBuffer(QByteArray *byteArray)
+{
+    Q_D(QBuffer);
+    if (isOpen()) {
+        qWarning("QBuffer::setBuffer: Buffer is open");
+        return;
+    }
+    if (byteArray) {
+        d->buf = byteArray;
+    } else {
+        d->buf = &d->defaultBuf;
+    }
+    d->defaultBuf.clear();
+    d->ioIndex = 0;
+}
+
+/*!
+    Returns a reference to the QBuffer's internal buffer. You can use
+    it to modify the QByteArray behind the QBuffer's back.
+
+    \sa setBuffer(), data()
+*/
+
+QByteArray &QBuffer::buffer()
+{
+    Q_D(QBuffer);
+    return *d->buf;
+}
+
+/*!
+    \overload
+
+    This is the same as data().
+*/
+
+const QByteArray &QBuffer::buffer() const
+{
+    Q_D(const QBuffer);
+    return *d->buf;
+}
+
+
+/*!
+    Returns the data contained in the buffer.
+
+    This is the same as buffer().
+
+    \sa setData(), setBuffer()
+*/
+
+const QByteArray &QBuffer::data() const
+{
+    Q_D(const QBuffer);
+    return *d->buf;
+}
+
+/*!
+    Sets the contents of the internal buffer to be \a data. This is
+    the same as assigning \a data to buffer().
+
+    Does nothing if isOpen() is true.
+
+    \sa setBuffer()
+*/
+void QBuffer::setData(const QByteArray &data)
+{
+    Q_D(QBuffer);
+    if (isOpen()) {
+        qWarning("QBuffer::setData: Buffer is open");
+        return;
+    }
+    *d->buf = data;
+    d->ioIndex = 0;
+}
+
+/*!
+    \fn void QBuffer::setData(const char *data, int size)
+
+    \overload
+
+    Sets the contents of the internal buffer to be the first \a size
+    bytes of \a data.
+*/
+
+/*!
+   \reimp
+*/
+bool QBuffer::open(OpenMode flags)
+{
+    Q_D(QBuffer);
+
+    if ((flags & Append) == Append)
+        flags |= WriteOnly;
+    setOpenMode(flags);
+    if (!(isReadable() || isWritable())) {
+        qWarning("QFile::open: File access not specified");
+        return false;
+    }
+
+    if ((flags & QIODevice::Truncate) == QIODevice::Truncate) {
+        d->buf->resize(0);
+    }
+    if ((flags & QIODevice::Append) == QIODevice::Append) // append to end of buffer
+        seek(d->buf->size());
+    else
+        seek(0);
+
+    return true;
+}
+
+/*!
+    \reimp
+*/
+void QBuffer::close()
+{
+    QIODevice::close();
+}
+
+/*!
+    \reimp
+*/
+qint64 QBuffer::pos() const
+{
+    return QIODevice::pos();
+}
+
+/*!
+    \reimp
+*/
+qint64 QBuffer::size() const
+{
+    Q_D(const QBuffer);
+    return qint64(d->buf->size());
+}
+
+/*!
+    \reimp
+*/
+bool QBuffer::seek(qint64 pos)
+{
+    Q_D(QBuffer);
+    if (pos > d->buf->size() && isWritable()) {
+        if (seek(d->buf->size())) {
+            const qint64 gapSize = pos - d->buf->size();
+            if (write(QByteArray(gapSize, 0)) != gapSize) {
+                qWarning("QBuffer::seek: Unable to fill gap");
+                return false;
+            }
+        } else {
+            return false;
+        }
+    } else if (pos > d->buf->size() || pos < 0) {
+        qWarning("QBuffer::seek: Invalid pos: %d", int(pos));
+        return false;
+    }
+    d->ioIndex = int(pos);
+    return QIODevice::seek(pos);
+}
+
+/*!
+    \reimp
+*/
+bool QBuffer::atEnd() const
+{
+    return QIODevice::atEnd();
+}
+
+/*!
+   \reimp
+*/
+bool QBuffer::canReadLine() const
+{
+    Q_D(const QBuffer);
+    if (!isOpen())
+        return false;
+
+    return d->buf->indexOf('\n', int(pos())) != -1 || QIODevice::canReadLine();
+}
+
+/*!
+    \reimp
+*/
+qint64 QBuffer::readData(char *data, qint64 len)
+{
+    Q_D(QBuffer);
+    if ((len = qMin(len, qint64(d->buf->size()) - d->ioIndex)) <= 0)
+        return qint64(0);
+    memcpy(data, d->buf->constData() + d->ioIndex, len);
+    d->ioIndex += int(len);
+    return len;
+}
+
+/*!
+    \reimp
+*/
+qint64 QBuffer::writeData(const char *data, qint64 len)
+{
+    Q_D(QBuffer);
+    int extraBytes = d->ioIndex + len - d->buf->size();
+    if (extraBytes > 0) { // overflow
+        int newSize = d->buf->size() + extraBytes;
+        d->buf->resize(newSize);
+        if (d->buf->size() != newSize) { // could not resize
+            qWarning("QBuffer::writeData: Memory allocation error");
+            return -1;
+        }
+    }
+
+    memcpy(d->buf->data() + d->ioIndex, (uchar *)data, int(len));
+    d->ioIndex += int(len);
+
+#ifndef QT_NO_QOBJECT
+    d->writtenSinceLastEmit += len;
+    if (d->signalConnectionCount && !d->signalsEmitted && !signalsBlocked()) {
+        d->signalsEmitted = true;
+        QMetaObject::invokeMethod(this, "_q_emitSignals", Qt::QueuedConnection);
+    }
+#endif
+    return len;
+}
+
+#ifndef QT_NO_QOBJECT
+/*!
+    \reimp
+    \internal
+*/
+void QBuffer::connectNotify(const char *signal)
+{
+    if (strcmp(signal + 1, "readyRead()") == 0 || strcmp(signal + 1, "bytesWritten(qint64)") == 0)
+        d_func()->signalConnectionCount++;
+}
+
+/*!
+    \reimp
+    \internal
+*/
+void QBuffer::disconnectNotify(const char *signal)
+{
+    if (!signal || strcmp(signal + 1, "readyRead()") == 0 || strcmp(signal + 1, "bytesWritten(qint64)") == 0)
+        d_func()->signalConnectionCount--;
+}
+#endif
+
+QT_END_NAMESPACE
+
+#ifndef QT_NO_QOBJECT
+# include "moc_qbuffer.cpp"
+#endif
+