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/****************************************************************************
**
** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies).
** All rights reserved.
** Contact: Nokia Corporation (qt-info@nokia.com)
**
** This file is part of the QtNetwork module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:BSD$
** You may use this file under the terms of the BSD license as follows:
**
** "Redistribution and use in source and binary forms, with or without
** modification, are permitted provided that the following conditions are
** met:
** * Redistributions of source code must retain the above copyright
** notice, this list of conditions and the following disclaimer.
** * Redistributions in binary form must reproduce the above copyright
** notice, this list of conditions and the following disclaimer in
** the documentation and/or other materials provided with the
** distribution.
** * Neither the name of Nokia Corporation and its Subsidiary(-ies) nor
** the names of its contributors may be used to endorse or promote
** products derived from this software without specific prior written
** permission.
**
** THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
** "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
** LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
** A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
** OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
** SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
** LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
** DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
** THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
** (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
** OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE."
** $QT_END_LICENSE$
**
****************************************************************************/
#include <QtCore>
void slowOperation1()
{
static char buf[256];
for (int i = 0; i < (1<<20); ++i)
buf[i % sizeof buf] = i;
}
void slowOperation2(int) { slowOperation1(); }
void startExample()
{
//![0]
QElapsedTimer timer;
timer.start();
slowOperation1();
qDebug() << "The slow operation took" << timer.elapsed() << "milliseconds";
//![0]
}
//![1]
void executeSlowOperations(int timeout)
{
QElapsedTimer timer;
timer.start();
slowOperation1();
int remainingTime = timeout - timer.elapsed();
if (remainingTime > 0)
slowOperation2(remainingTime);
}
//![1]
//![2]
void executeOperationsForTime(int ms)
{
QElapsedTimer timer;
timer.start();
while (!timer.hasExpired(ms))
slowOperation1();
}
//![2]
int restartExample()
{
//![3]
QElapsedTimer timer;
int count = 1;
timer.start();
do {
count *= 2;
slowOperation2(count);
} while (timer.restart() < 250);
return count;
//![3]
}
int main(int argc, char **argv)
{
QCoreApplication app(argc, argv);
startExample();
restartExample();
executeSlowOperations(5);
executeOperationsForTime(5);
}
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