Add Qt3 development HEAD version

1 files changed, 360 insertions, 0 deletions

diff --git a/src/kernel/qasyncio.cpp b/src/kernel/qasyncio.cpp
new file mode 100644
index 0000000..b29dfa6
--- /dev/null
+++ b/src/kernel/qasyncio.cpp
@@ -0,0 +1,360 @@
+/****************************************************************************
+**
+** Implementation of asynchronous I/O classes
+**
+** Created : 970617
+**
+** Copyright (C) 1992-2008 Trolltech ASA.  All rights reserved.
+**
+** This file is part of the kernel 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 [email protected].
+**
+** 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 "qasyncio.h"
+#include "qiodevice.h"
+#include <stdlib.h>
+
+#ifndef QT_NO_ASYNC_IO
+
+/*!
+  \class QAsyncIO qasyncio.h
+  \obsolete
+  \brief The QAsyncIO class encapsulates I/O asynchronicity.
+
+  The Qt classes for asynchronous input/output provide a simple
+  mechanism to allow large files or slow data sources to be processed
+  without using large amounts of memory or blocking the user interface.
+
+  This facility is used in Qt to drive animated images.  See QImageConsumer.
+*/
+
+
+/*!
+  Destroys the async IO object.
+*/
+QAsyncIO::~QAsyncIO()
+{
+}
+
+/*!
+  Ensures that only one object, \a obj and function, \a member, can
+  respond to changes in readiness.
+*/
+void QAsyncIO::connect(QObject* obj, const char *member)
+{
+    signal.disconnect(0, 0);
+    signal.connect(obj, member);
+}
+
+/*!
+  Derived classes should call this when they change from being
+  unready to ready.
+*/
+void QAsyncIO::ready()
+{
+    signal.activate();
+}
+
+
+
+/*!
+  \class QDataSink qasyncio.h
+  \obsolete
+  \brief The QDataSink class is an asynchronous consumer of data.
+
+  A data sink is an object which receives data from some source in an
+  asynchronous manner.  This means that at some time not determined by
+  the data sink, blocks of data are given to it from processing.  The
+  data sink is able to limit the maximum size of such blocks which it
+  is currently able to process.
+
+  \sa QAsyncIO, QDataSource, QDataPump
+*/
+
+/*!
+  \fn int QDataSink::readyToReceive()
+
+  The data sink should return a value indicating how much data it is ready
+  to consume.  This may be 0.
+*/
+
+/*!
+  This should be called whenever readyToReceive() might have become non-zero.
+  It is merely calls QAsyncIO::ready() if readyToReceive() is non-zero.
+*/
+void QDataSink::maybeReady()
+{
+    if (readyToReceive()) ready();
+}
+
+/*!
+  \fn void QDataSink::receive(const uchar*, int count)
+
+  This function is called to provide data for the data sink.  The \a count
+  will be no more than the amount indicated by the most recent call to
+  readyToReceive().  The sink must use all the provided data.
+*/
+
+/*!
+  \fn void QDataSink::eof()
+
+  This function will be called when no more data is available for
+  processing.
+*/
+
+
+/*!
+  \class QDataSource qasyncio.h
+  \obsolete
+  \brief The QDataSource class is an asynchronous producer of data.
+
+  A data source is an object which provides data from some source in an
+  asynchronous manner.  This means that at some time not determined by
+  the data source, blocks of data will be taken from it for processing.
+  The data source is able to limit the maximum size of such blocks which
+  it is currently able to provide.
+
+  \sa QAsyncIO, QDataSink, QDataPump
+*/
+
+/*!
+  \fn int QDataSource::readyToSend()
+
+  The data source should return a value indicating how much data it is ready
+  to provide.  This may be 0.  If the data source knows it will never be
+  able to provide any more data (until after a rewind()), it may return -1.
+*/
+
+/*!
+  This should be called whenever readyToSend() might have become non-zero.
+  It is merely calls QAsyncIO::ready() if readyToSend() is non-zero.
+*/
+void QDataSource::maybeReady()
+{
+    if (readyToSend()) ready();
+}
+
+/*!
+  \fn void QDataSource::sendTo(QDataSink*, int count)
+
+  This function is called to extract data from the source, by sending
+  it to the given data sink.  The \a count will be no more than the amount
+  indicated by the most recent call to readyToSend().  The source must
+  use all the provided data, and the sink will be prepared to accept at
+  least this much data.
+*/
+
+/*!
+  This function should return TRUE if the data source can be rewound.
+
+  The default returns FALSE.
+*/
+bool QDataSource::rewindable() const
+{
+    return FALSE;
+}
+
+/*!
+  If this function is called with \a on set to TRUE, and rewindable()
+  is TRUE, then the data source must take measures to allow the rewind()
+  function to subsequently operate as described.  If rewindable() is FALSE,
+  the function should call QDataSource::enableRewind(), which aborts with
+  a qFatal() error.
+
+  For example, a network connection may choose to use a disk cache
+  of input only if rewinding is enabled before the first buffer-full of
+  data is discarded, returning FALSE in rewindable() if that first buffer
+  is discarded.
+*/
+void QDataSource::enableRewind( bool /* on */ )
+{
+    qFatal( "Attempted to make unrewindable QDataSource rewindable" );
+}
+
+/*!
+  This function rewinds the data source.  This may only be called if
+  enableRewind(TRUE) has been previously called.
+*/
+void QDataSource::rewind()
+{
+    qFatal("Attempted to rewind unrewindable QDataSource");
+}
+
+/*!
+  \class QIODeviceSource qasyncio.h
+  \obsolete
+  \brief The QIODeviceSource class is a QDataSource that draws data from a QIODevice.
+
+  This class encapsulates retrieving data from a QIODevice (such as a QFile).
+*/
+
+/*!
+  Constructs a QIODeviceSource from the QIODevice \a device.  The QIODevice
+  \e must be dynamically allocated, becomes owned by the QIODeviceSource,
+  and will be deleted when the QIODeviceSource is destroyed. \a buffer_size
+  determines the size of buffering to use between asynchronous operations.
+  The higher the \a buffer_size, the more efficient, but the less interleaved
+  the operation will be with other processing.
+*/
+QIODeviceSource::QIODeviceSource(QIODevice* device, int buffer_size) :
+    buf_size(buffer_size),
+    buffer(new uchar[buf_size]),
+    iod(device),
+    rew(FALSE)
+{
+}
+
+/*!
+  Destroys the QIODeviceSource, deleting the QIODevice from which it was
+  constructed.
+*/
+QIODeviceSource::~QIODeviceSource()
+{
+    delete iod;
+    delete [] buffer;
+}
+
+/*!
+  Ready until end-of-file.
+*/
+int QIODeviceSource::readyToSend()
+{
+    if ( iod->status() != IO_Ok || !(iod->state() & IO_Open) )
+	return -1;
+
+    int n = QMIN((uint)buf_size, iod->size()-iod->at()); // ### not 64-bit safe
+                                                         // ### not large file safe
+    return n ? n : -1;
+}
+
+/*!
+  Reads a block of data and sends up to \a n bytes to the \a sink.
+*/
+void QIODeviceSource::sendTo(QDataSink* sink, int n)
+{
+    iod->readBlock((char*)buffer, n);
+    sink->receive(buffer, n);
+}
+
+/*!
+  All QIODeviceSource's are rewindable.
+*/
+bool QIODeviceSource::rewindable() const
+{
+    return TRUE;
+}
+
+/*!
+  If \a on is set to TRUE then rewinding is enabled.  
+  No special action is taken.  If \a on is set to 
+  FALSE then rewinding is disabled.
+*/
+void QIODeviceSource::enableRewind(bool on)
+{
+    rew = on;
+}
+
+/*!
+  Calls reset() on the QIODevice.
+*/
+void QIODeviceSource::rewind()
+{
+    if (!rew) {
+	QDataSource::rewind();
+    } else {
+	iod->reset();
+	ready();
+    }
+}
+
+
+/*!
+  \class QDataPump qasyncio.h
+  \obsolete
+  \brief The QDataPump class moves data from a QDataSource to a QDataSink during event processing.
+
+  For a QDataSource to provide data to a QDataSink, a controller must exist
+  to examine the QDataSource::readyToSend() and QDataSink::readyToReceive()
+  methods and respond to the QASyncIO::activate() signal of the source and
+  sink.  One very useful way to do this is interleaved with other event
+  processing.  QDataPump provides this - create a pipe between a source
+  and a sink, and data will be moved during subsequent event processing.
+
+  Note that each source can only provide data to one sink and each sink
+  can only receive data from one source (although it is quite possible
+  to write a multiplexing sink that is multiple sources).
+*/
+
+/*!
+  Constructs a QDataPump to move data from a given \a data_source
+  to a given \a data_sink.
+*/
+QDataPump::QDataPump(QDataSource* data_source, QDataSink* data_sink) :
+    source(data_source), sink(data_sink)
+{
+    source->connect(this, SLOT(kickStart()));
+    sink->connect(this, SLOT(kickStart()));
+    connect(&timer, SIGNAL(timeout()), this, SLOT(tryToPump()));
+    timer.start(0, TRUE);
+}
+
+void QDataPump::kickStart()
+{
+    if (!timer.isActive()) {
+	interval = 0;
+	timer.start(0, TRUE);
+    }
+}
+
+void QDataPump::tryToPump()
+{
+    int supply, demand;
+
+    supply = source->readyToSend();
+    demand = sink->readyToReceive();
+    if (demand <= 0) {
+	return;
+    }
+    interval = 0;
+    if (supply < 0) {
+	// All done (until source signals change in readiness)
+	sink->eof();
+	return;
+    }
+    if (!supply)
+	return;
+    source->sendTo(sink, QMIN(supply, demand));
+
+    timer.start(0, TRUE);
+}
+
+#endif // QT_NO_ASYNC_IO
+