Long live Qt 4.5!

3 files changed, 845 insertions, 0 deletions

diff --git a/tests/auto/qthreadpool/.gitignore b/tests/auto/qthreadpool/.gitignore
new file mode 100644
index 0000000..1610582
--- /dev/null
+++ b/tests/auto/qthreadpool/.gitignore
@@ -0,0 +1 @@
+tst_qthreadpool
diff --git a/tests/auto/qthreadpool/qthreadpool.pro b/tests/auto/qthreadpool/qthreadpool.pro
new file mode 100644
index 0000000..3f6ea64
--- /dev/null
+++ b/tests/auto/qthreadpool/qthreadpool.pro
@@ -0,0 +1,3 @@
+load(qttest_p4)
+SOURCES += tst_qthreadpool.cpp
+QT = core
diff --git a/tests/auto/qthreadpool/tst_qthreadpool.cpp b/tests/auto/qthreadpool/tst_qthreadpool.cpp
new file mode 100644
index 0000000..9bb39d0
--- /dev/null
+++ b/tests/auto/qthreadpool/tst_qthreadpool.cpp
@@ -0,0 +1,841 @@
+/****************************************************************************
+**
+** Copyright (C) 2009 Nokia Corporation and/or its subsidiary(-ies).
+** Contact: Qt Software Information (qt-info@nokia.com)
+**
+** This file is part of the test suite 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 either Technology Preview License Agreement or the
+** Beta Release License Agreement.
+**
+** 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 1.0, included in the file LGPL_EXCEPTION.txt in this
+** package.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3.0 as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU General Public License version 3.0 requirements will be
+** met: http://www.gnu.org/copyleft/gpl.html.
+**
+** If you are unsure which license is appropriate for your use, please
+** contact the sales department at qt-sales@nokia.com.
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+#include <QtTest/QtTest>
+#include <qdatetime.h>
+#include <qthreadpool.h>
+#include <qstring.h>
+#include <qmutex.h>
+
+typedef void (*FunctionPointer)();
+
+class FunctionPointerTask : public QRunnable
+{
+public:
+    FunctionPointerTask(FunctionPointer function)
+    :function(function) {}
+    void run() { function(); }
+private:
+    FunctionPointer function;
+};
+
+QRunnable *createTask(FunctionPointer pointer)
+{
+    return new FunctionPointerTask(pointer);
+}
+
+class tst_QThreadPool : public QObject
+{
+    Q_OBJECT
+private slots:
+    void runFunction();
+    void createThreadRunFunction();
+    void runMultiple();
+    void waitcomplete();
+    void runTask();
+    void singleton();
+    void destruction();
+    void threadRecycling();
+    void expiryTimeout();
+    void exceptions();
+    void maxThreadCount();
+    void setMaxThreadCount_data();
+    void setMaxThreadCount();
+    void setMaxThreadCountStartsAndStopsThreads();
+    void activeThreadCount();
+    void reserveThread_data();
+    void reserveThread();
+    void releaseThread_data();
+    void releaseThread();
+    void start();
+    void tryStart();
+    void tryStartPeakThreadCount();
+    void tryStartCount();
+    void waitForDone();
+    void destroyingWaitsForTasksToFinish();
+    void stressTest();
+};
+
+int testFunctionCount;
+
+void sleepTestFunction()
+{
+    QTest::qSleep(1000);
+    ++testFunctionCount;
+}
+
+void emptyFunct()
+{
+
+}
+
+void noSleepTestFunction()
+{
+    ++testFunctionCount;
+}
+
+void sleepTestFunctionMutex()
+{
+    static QMutex testMutex;
+    QTest::qSleep(1000);
+    testMutex.lock();
+    ++testFunctionCount;
+    testMutex.unlock();
+}
+
+void noSleepTestFunctionMutex()
+{
+    static QMutex testMutex;
+    testMutex.lock();
+    ++testFunctionCount;
+    testMutex.unlock();
+}
+
+void tst_QThreadPool::runFunction()
+{
+    {
+        QThreadPool manager;
+        testFunctionCount = 0;
+        manager.start(createTask(noSleepTestFunction));
+    }
+    QCOMPARE(testFunctionCount, 1);
+}
+
+void tst_QThreadPool::createThreadRunFunction()
+{
+    {
+        QThreadPool manager;
+        testFunctionCount = 0;
+        manager.start(createTask(noSleepTestFunction));
+    }
+
+    QCOMPARE(testFunctionCount, 1);
+}
+
+void tst_QThreadPool::runMultiple()
+{
+    const int runs = 10;
+
+    {
+        QThreadPool manager;
+        testFunctionCount = 0;
+        for (int i = 0; i < runs; ++i) {
+            manager.start(createTask(sleepTestFunctionMutex));
+        }
+    }
+    QCOMPARE(testFunctionCount, runs);
+
+    {
+        QThreadPool manager;
+        testFunctionCount = 0;
+        for (int i = 0; i < runs; ++i) {
+            manager.start(createTask(noSleepTestFunctionMutex));
+        }
+    }
+    QCOMPARE(testFunctionCount, runs);
+
+    {
+        QThreadPool manager;
+        for (int i = 0; i < 500; ++i)
+            manager.start(createTask(emptyFunct));
+    }
+}
+
+void tst_QThreadPool::waitcomplete()
+{
+    testFunctionCount = 0;
+    const int runs = 500;
+    for (int i = 0; i < 500; ++i) {
+        QThreadPool pool;
+        pool.start(createTask(noSleepTestFunction));
+    }
+    QCOMPARE(testFunctionCount, runs);
+}
+
+volatile bool ran;
+class TestTask : public QRunnable
+{
+public:
+    void run()
+    {
+        ran = true;
+    }
+};
+
+void tst_QThreadPool::runTask()
+{
+    QThreadPool manager;
+    ran = false;
+    manager.start(new TestTask());
+    // Hang if task is not runned.
+    while (ran == false);
+}
+
+/*
+    Test running via QThreadPool::globalInstance()
+*/
+void tst_QThreadPool::singleton()
+{
+    ran = false;
+    QThreadPool::globalInstance()->start(new TestTask());
+    while (ran == false);
+}
+
+int *value = 0;
+class IntAccessor : public QRunnable
+{
+public:
+    void run()
+    {
+        for (int i = 0; i < 100; ++i) {
+            ++(*value);
+            QTest::qSleep(1);
+        }
+    }
+};
+
+/*
+    Test that the ThreadManager destructor waits until
+    all threads have completed.
+*/
+void tst_QThreadPool::destruction()
+{
+    value = new int;
+    QThreadPool *threadManager = new QThreadPool();
+    threadManager->start(new IntAccessor());
+    threadManager->start(new IntAccessor());
+    delete threadManager;
+    delete value;
+    value = 0;
+}
+
+QSemaphore threadRecyclingSemaphore;
+QThread *recycledThread = 0;
+
+class ThreadRecorderTask : public QRunnable
+{
+public:
+    void run()
+    {
+        recycledThread = QThread::currentThread();
+        threadRecyclingSemaphore.release();
+    }
+};
+
+/*
+    Test that the thread pool really reuses threads.
+*/
+void tst_QThreadPool::threadRecycling()
+{
+    QThreadPool threadPool;
+
+    threadPool.start(new ThreadRecorderTask());
+    threadRecyclingSemaphore.acquire();
+    QThread *thread1 = recycledThread;
+
+    QTest::qSleep(100);
+
+    threadPool.start(new ThreadRecorderTask());
+    threadRecyclingSemaphore.acquire();
+    QThread *thread2 = recycledThread;
+    QCOMPARE(thread1, thread2);
+
+    QTest::qSleep(100);
+
+    threadPool.start(new ThreadRecorderTask());
+    threadRecyclingSemaphore.acquire();
+    QThread *thread3 = recycledThread;
+    QCOMPARE(thread2, thread3);
+}
+
+class ExpiryTimeoutTask : public QRunnable
+{
+public:
+    QThread *thread;
+    int runCount;
+    QSemaphore semaphore;
+
+    ExpiryTimeoutTask()
+        : thread(0), runCount(0)
+    {
+        setAutoDelete(false);
+    }
+
+    void run()
+    {
+        thread = QThread::currentThread();
+        ++runCount;
+        semaphore.release();
+    }
+};
+
+void tst_QThreadPool::expiryTimeout()
+{
+    ExpiryTimeoutTask task;
+
+    QThreadPool threadPool;
+    threadPool.setMaxThreadCount(1);
+
+    int expiryTimeout = threadPool.expiryTimeout();
+    threadPool.setExpiryTimeout(1000);
+    QCOMPARE(threadPool.expiryTimeout(), 1000);
+
+    // run the task
+    threadPool.start(&task);
+    QVERIFY(task.semaphore.tryAcquire(1, 10000));
+    QCOMPARE(task.runCount, 1);
+    QVERIFY(!task.thread->wait(100));
+    // thread should expire
+    QThread *firstThread = task.thread;
+    QVERIFY(task.thread->wait(10000));
+
+    // run task again, thread should be restarted
+    threadPool.start(&task);
+    QVERIFY(task.semaphore.tryAcquire(1, 10000));
+    QCOMPARE(task.runCount, 2);
+    QVERIFY(!task.thread->wait(100));
+    // thread should expire again
+    QVERIFY(task.thread->wait(10000));
+
+    // thread pool should have reused the expired thread (instead of
+    // starting a new one)
+    QCOMPARE(firstThread, task.thread);
+
+    threadPool.setExpiryTimeout(expiryTimeout);
+    QCOMPARE(threadPool.expiryTimeout(), expiryTimeout);
+}
+
+#ifndef QT_NO_EXCEPTIONS
+class ExceptionTask : public QRunnable
+{
+public:
+    void run()
+    {
+        throw new int;
+    }
+};
+#endif
+
+void tst_QThreadPool::exceptions()
+{
+#ifndef QT_NO_EXCEPTIONS
+    ExceptionTask task;
+    {
+        QThreadPool threadPool;
+//  Uncomment this for a nice crash.
+//        threadPool.start(&task);
+    }
+#else
+    QSKIP("No exception support", SkipAll);
+#endif
+}
+
+void tst_QThreadPool::maxThreadCount()
+{
+    DEPENDS_ON("setMaxThreadCount()");
+}
+
+void tst_QThreadPool::setMaxThreadCount_data()
+{
+    QTest::addColumn<int>("limit");
+
+    QTest::newRow("") << 1;
+    QTest::newRow("") << -1;
+    QTest::newRow("") << 2;
+    QTest::newRow("") << -2;
+    QTest::newRow("") << 4;
+    QTest::newRow("") << -4;
+    QTest::newRow("") << 0;
+    QTest::newRow("") << 12345;
+    QTest::newRow("") << -6789;
+    QTest::newRow("") << 42;
+    QTest::newRow("") << -666;
+}
+
+void tst_QThreadPool::setMaxThreadCount()
+{
+    QFETCH(int, limit);
+    QThreadPool *threadPool = QThreadPool::globalInstance();
+    int savedLimit = threadPool->maxThreadCount();
+
+    // maxThreadCount() should always return the previous argument to
+    // setMaxThreadCount(), regardless of input
+    threadPool->setMaxThreadCount(limit);
+    QCOMPARE(threadPool->maxThreadCount(), limit);
+
+    // the value returned from maxThreadCount() should always be valid input for setMaxThreadCount()
+    threadPool->setMaxThreadCount(savedLimit);
+    QCOMPARE(threadPool->maxThreadCount(), savedLimit);
+
+    // setting the limit on children should have no effect on the parent
+    {
+        QThreadPool threadPool2(threadPool);
+        savedLimit = threadPool2.maxThreadCount();
+
+        // maxThreadCount() should always return the previous argument to
+        // setMaxThreadCount(), regardless of input
+        threadPool2.setMaxThreadCount(limit);
+        QCOMPARE(threadPool2.maxThreadCount(), limit);
+
+        // the value returned from maxThreadCount() should always be valid input for setMaxThreadCount()
+        threadPool2.setMaxThreadCount(savedLimit);
+        QCOMPARE(threadPool2.maxThreadCount(), savedLimit);
+    }
+}
+
+void tst_QThreadPool::setMaxThreadCountStartsAndStopsThreads()
+{
+    class WaitingTask : public QRunnable
+    {
+    public:
+        QSemaphore waitForStarted, waitToFinish;
+
+        WaitingTask() { setAutoDelete(false); }
+
+        void run()
+        {
+            waitForStarted.release();
+            waitToFinish.acquire();
+        }
+    };
+
+    QThreadPool threadPool;
+    threadPool.setMaxThreadCount(1);
+
+    WaitingTask *task = new WaitingTask;
+    threadPool.start(task);
+    QVERIFY(task->waitForStarted.tryAcquire(1, 1000));
+
+    // thread limit is 1, cannot start more tasks
+    threadPool.start(task);
+    QVERIFY(!task->waitForStarted.tryAcquire(1, 1000));
+
+    // increasing the limit by 1 should start the task immediately
+    threadPool.setMaxThreadCount(2);
+    QVERIFY(task->waitForStarted.tryAcquire(1, 1000));
+
+    // ... but we still cannot start more tasks
+    threadPool.start(task);
+    QVERIFY(!task->waitForStarted.tryAcquire(1, 1000));
+
+    // increasing the limit should be able to start more than one at a time
+    threadPool.start(task);
+    threadPool.setMaxThreadCount(4);
+    QVERIFY(task->waitForStarted.tryAcquire(2, 1000));
+
+    // ... but we still cannot start more tasks
+    threadPool.start(task);
+    threadPool.start(task);
+    QVERIFY(!task->waitForStarted.tryAcquire(2, 1000));
+
+    // decreasing the thread limit should cause the active thread count to go down
+    threadPool.setMaxThreadCount(2);
+    QCOMPARE(threadPool.activeThreadCount(), 4);
+    task->waitToFinish.release(2);
+    QTest::qWait(1000);
+    QCOMPARE(threadPool.activeThreadCount(), 2);
+
+    // ... and we still cannot start more tasks
+    threadPool.start(task);
+    threadPool.start(task);
+    QVERIFY(!task->waitForStarted.tryAcquire(2, 1000));
+
+    // start all remaining tasks
+    threadPool.start(task);
+    threadPool.start(task);
+    threadPool.start(task);
+    threadPool.start(task);
+    threadPool.setMaxThreadCount(8);
+    QVERIFY(task->waitForStarted.tryAcquire(6, 1000));
+
+    task->waitToFinish.release(10);
+//    delete task;
+}
+
+
+void tst_QThreadPool::activeThreadCount()
+{
+    DEPENDS_ON("tryReserveThread()");
+    DEPENDS_ON("reserveThread()");
+    DEPENDS_ON("releaseThread()");
+}
+
+void tst_QThreadPool::reserveThread_data()
+{
+    setMaxThreadCount_data();
+}
+
+void tst_QThreadPool::reserveThread()
+{
+    QFETCH(int, limit);
+    QThreadPool *threadpool = QThreadPool::globalInstance();
+    int savedLimit = threadpool->maxThreadCount();
+    threadpool->setMaxThreadCount(limit);
+
+    // reserve up to the limit
+    for (int i = 0; i < limit; ++i)
+        threadpool->reserveThread();
+
+    // reserveThread() should always reserve a thread, regardless of
+    // how many have been previously reserved
+    threadpool->reserveThread();
+    QCOMPARE(threadpool->activeThreadCount(), (limit > 0 ? limit : 0) + 1);
+    threadpool->reserveThread();
+    QCOMPARE(threadpool->activeThreadCount(), (limit > 0 ? limit : 0) + 2);
+
+    // cleanup
+    threadpool->releaseThread();
+    threadpool->releaseThread();
+    for (int i = 0; i < limit; ++i)
+        threadpool->releaseThread();
+
+    // reserving threads in children should not effect the parent
+    {
+        QThreadPool threadpool2(threadpool);
+        threadpool2.setMaxThreadCount(limit);
+
+        // reserve up to the limit
+        for (int i = 0; i < limit; ++i)
+            threadpool2.reserveThread();
+
+        // reserveThread() should always reserve a thread, regardless
+        // of how many have been previously reserved
+        threadpool2.reserveThread();
+        QCOMPARE(threadpool2.activeThreadCount(), (limit > 0 ? limit : 0) + 1);
+        threadpool2.reserveThread();
+        QCOMPARE(threadpool2.activeThreadCount(), (limit > 0 ? limit : 0) + 2);
+
+        threadpool->reserveThread();
+        QCOMPARE(threadpool->activeThreadCount(), 1);
+        threadpool->reserveThread();
+        QCOMPARE(threadpool->activeThreadCount(), 2);
+
+        // cleanup
+        threadpool2.releaseThread();
+        threadpool2.releaseThread();
+        threadpool->releaseThread();
+        threadpool->releaseThread();
+        while (threadpool2.activeThreadCount() > 0)
+            threadpool2.releaseThread();
+    }
+
+    // reset limit on global QThreadPool
+    threadpool->setMaxThreadCount(savedLimit);
+}
+
+void tst_QThreadPool::releaseThread_data()
+{
+    setMaxThreadCount_data();
+}
+
+void tst_QThreadPool::releaseThread()
+{
+    QFETCH(int, limit);
+    QThreadPool *threadpool = QThreadPool::globalInstance();
+    int savedLimit = threadpool->maxThreadCount();
+    threadpool->setMaxThreadCount(limit);
+
+    // reserve up to the limit
+    for (int i = 0; i < limit; ++i)
+        threadpool->reserveThread();
+
+    // release should decrease the number of reserved threads
+    int reserved = threadpool->activeThreadCount();
+    while (reserved-- > 0) {
+        threadpool->releaseThread();
+        QCOMPARE(threadpool->activeThreadCount(), reserved);
+    }
+    QCOMPARE(threadpool->activeThreadCount(), 0);
+
+    // releaseThread() can release more than have been reserved
+    threadpool->releaseThread();
+    QCOMPARE(threadpool->activeThreadCount(), -1);
+    threadpool->reserveThread();
+    QCOMPARE(threadpool->activeThreadCount(), 0);
+
+    // releasing threads in children should not effect the parent
+    {
+        QThreadPool threadpool2(threadpool);
+        threadpool2.setMaxThreadCount(limit);
+
+        // reserve up to the limit
+        for (int i = 0; i < limit; ++i)
+            threadpool2.reserveThread();
+
+        // release should decrease the number of reserved threads
+        int reserved = threadpool2.activeThreadCount();
+        while (reserved-- > 0) {
+            threadpool2.releaseThread();
+            QCOMPARE(threadpool2.activeThreadCount(), reserved);
+            QCOMPARE(threadpool->activeThreadCount(), 0);
+        }
+        QCOMPARE(threadpool2.activeThreadCount(), 0);
+        QCOMPARE(threadpool->activeThreadCount(), 0);
+
+        // releaseThread() can release more than have been reserved
+        threadpool2.releaseThread();
+        QCOMPARE(threadpool2.activeThreadCount(), -1);
+        QCOMPARE(threadpool->activeThreadCount(), 0);
+        threadpool2.reserveThread();
+        QCOMPARE(threadpool2.activeThreadCount(), 0);
+        QCOMPARE(threadpool->activeThreadCount(), 0);
+    }
+
+    // reset limit on global QThreadPool
+    threadpool->setMaxThreadCount(savedLimit);
+}
+
+QAtomicInt count;
+class CountingRunnable : public QRunnable
+{
+    public: void run()
+    {
+        count.ref();
+    }
+};
+
+void tst_QThreadPool::start()
+{
+    const int runs = 1000;
+    count = 0;
+    {
+        QThreadPool threadPool;
+        for (int i = 0; i< runs; ++i) {
+            threadPool.start(new CountingRunnable());
+        }
+    }
+    QCOMPARE(int(count), runs);
+}
+
+void tst_QThreadPool::tryStart()
+{
+    class WaitingTask : public QRunnable
+    {
+    public:
+        QSemaphore semaphore;
+
+        WaitingTask() { setAutoDelete(false); }
+
+        void run()
+        {
+            semaphore.acquire();
+            count.ref();
+        }
+    };
+
+    count = 0;
+
+    WaitingTask task;
+    QThreadPool threadPool;
+    for (int i = 0; i < threadPool.maxThreadCount(); ++i) {
+        threadPool.start(&task);
+    }
+    QVERIFY(!threadPool.tryStart(&task));
+    task.semaphore.release(threadPool.maxThreadCount());
+    threadPool.waitForDone();
+    QCOMPARE(int(count), threadPool.maxThreadCount());
+}
+
+QMutex mutex;
+int activeThreads = 0;
+int peakActiveThreads = 0;
+void tst_QThreadPool::tryStartPeakThreadCount()
+{
+    class CounterTask : public QRunnable
+    {
+    public:
+        CounterTask() { setAutoDelete(false); }
+
+        void run()
+        {
+            {
+                QMutexLocker lock(&mutex);
+                ++activeThreads;
+                peakActiveThreads = qMax(peakActiveThreads, activeThreads);
+            }
+
+            QTest::qWait(100);
+            {
+                QMutexLocker lock(&mutex);
+                --activeThreads;
+            }
+        }
+    };
+
+    CounterTask task;
+    QThreadPool threadPool;
+
+    for (int i = 0; i < 20; ++i) {
+        if (threadPool.tryStart(&task) == false)
+            QTest::qWait(10);
+    }
+    QCOMPARE(peakActiveThreads, QThread::idealThreadCount());
+
+    for (int i = 0; i < 20; ++i) {
+        if (threadPool.tryStart(&task) == false)
+            QTest::qWait(10);
+    }
+    QCOMPARE(peakActiveThreads, QThread::idealThreadCount());
+}
+
+void tst_QThreadPool::tryStartCount()
+{
+    class SleeperTask : public QRunnable
+    {
+    public:
+        SleeperTask() { setAutoDelete(false); }
+
+        void run()
+        {
+            QTest::qWait(50);
+        }
+    };
+
+    SleeperTask task;
+    QThreadPool threadPool;
+    const int runs = 5;
+
+    for (int i = 0; i < runs; ++i) {
+//        qDebug() << "iteration" << i;
+        int count = 0;
+        while (threadPool.tryStart(&task))
+            ++count;
+        QCOMPARE(count, QThread::idealThreadCount());
+
+        QTest::qWait(100);
+    }
+}
+
+void tst_QThreadPool::waitForDone()
+{
+    QTime total, pass;
+    total.start();
+
+    QThreadPool threadPool;
+    while (total.elapsed() < 10000) {
+        int runs;
+        runs = count = 0;
+        pass.restart();
+        while (pass.elapsed() < 100) {
+            threadPool.start(new CountingRunnable());
+            ++runs;
+        }
+        threadPool.waitForDone();
+        QCOMPARE(int(count), runs);
+
+        runs = count = 0;
+        pass.restart();
+        while (pass.elapsed() < 100) {
+            threadPool.start(new CountingRunnable());
+            threadPool.start(new CountingRunnable());
+            runs += 2;
+        }
+        threadPool.waitForDone();
+        QCOMPARE(int(count), runs);
+    }
+}
+
+void tst_QThreadPool::destroyingWaitsForTasksToFinish()
+{
+    QTime total, pass;
+    total.start();
+
+    while (total.elapsed() < 10000) {
+        int runs;
+        runs = count = 0;
+        {
+            QThreadPool threadPool;
+            pass.restart();
+            while (pass.elapsed() < 100) {
+                threadPool.start(new CountingRunnable());
+                ++runs;
+            }
+        }
+        QCOMPARE(int(count), runs);
+
+        runs = count = 0;
+        {
+            QThreadPool threadPool;
+            pass.restart();
+            while (pass.elapsed() < 100) {
+                threadPool.start(new CountingRunnable());
+                threadPool.start(new CountingRunnable());
+                runs += 2;
+            }
+        }
+        QCOMPARE(int(count), runs);
+    }
+}
+
+void tst_QThreadPool::stressTest()
+{
+    class Task : public QRunnable
+    {
+        QSemaphore semaphore;
+    public:
+        Task() { setAutoDelete(false); }
+
+        void start()
+        {
+            QThreadPool::globalInstance()->start(this);
+        }
+
+        void wait()
+        {
+            semaphore.acquire();
+        }
+
+        void run()
+        {
+            semaphore.release();
+        }
+    };
+
+    QTime total;
+    total.start();
+    while (total.elapsed() < 30000) {
+        Task t;
+        t.start();
+        t.wait();
+    }
+}
+
+QTEST_MAIN(tst_QThreadPool);
+#include "tst_qthreadpool.moc"