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** this package.

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** General Public License version 2.1 as published by the Free Software

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****************************************************************************/

#include "qthread.h"

#include "qthreadstorage.h"

#include "qmutex.h"

#include "qmutexpool_p.h"

#include "qreadwritelock.h"

#include "qabstracteventdispatcher.h"

#include <qeventloop.h>

#include <qhash.h>

#include "qthread_p.h"

#include "private/qcoreapplication_p.h"

/*

#ifdef Q_OS_WIN32

# include "qt_windows.h"

#else

# include <unistd.h>

# include <netinet/in.h>

# include <sys/utsname.h>

# include <sys/socket.h>

*/

/*

#  elif defined(Q_OS_HPUX)

#   include <sys/pstat.h>

#  elif defined(Q_OS_FREEBSD) || defined(Q_OS_OPENBSD) || defined(Q_OS_MAC)

#   include <sys/sysctl.h>

#  endif

#endif

*/

QT_BEGIN_NAMESPACE

/*

  QThreadData

*/

QThreadData::QThreadData(int initialRefCount)

    : _ref(initialRefCount), thread(0),

      quitNow(false), loopLevel(0), eventDispatcher(0), canWait(true)

{

    // fprintf(stderr, "QThreadData %p created\n", this);

}

QThreadData::~QThreadData()

{

    Q_ASSERT(_ref == 0);

    // In the odd case that Qt is running on a secondary thread, the main

    // thread instance will have been dereffed asunder because of the deref in

    // QThreadData::current() and the deref in the pthread_destroy. To avoid

    // crashing during QCoreApplicationData's global static cleanup we need to

    // safeguard the main thread here.. This fix is a bit crude, but it solves

    // the problem...

    if (this->thread == QCoreApplicationPrivate::theMainThread) {

       QCoreApplicationPrivate::theMainThread = 0;

    }

    QThread *t = thread;

    thread = 0;

    delete t;

    for (int i = 0; i < postEventList.size(); ++i) {

        const QPostEvent &pe = postEventList.at(i);

        if (pe.event) {

            --pe.receiver->d_func()->postedEvents;

            pe.event->posted = false;

            delete pe.event;

        }

    }

    // fprintf(stderr, "QThreadData %p destroyed\n", this);

}

void QThreadData::ref()

{

#ifndef QT_NO_THREAD

    (void) _ref.ref();

    Q_ASSERT(_ref != 0);

#endif

}

void QThreadData::deref()

{

#ifndef QT_NO_THREAD

    if (!_ref.deref())

        delete this;

#endif

}

/*

  QAdoptedThread

*/

QAdoptedThread::QAdoptedThread(QThreadData *data)

    : QThread(*new QThreadPrivate(data))

{

    // thread should be running and not finished for the lifetime

    // of the application (even if QCoreApplication goes away)

#ifndef QT_NO_THREAD

    d_func()->running = true;

    d_func()->finished = false;

    init();

#endif

    // fprintf(stderr, "new QAdoptedThread = %p\n", this);

}

QAdoptedThread::~QAdoptedThread()

{

#ifndef QT_NO_THREAD

    QThreadPrivate::finish(this);

#endif

    // fprintf(stderr, "~QAdoptedThread = %p\n", this);

}

QThread *QAdoptedThread::createThreadForAdoption()

{

    QScopedPointer<QThread> t(new QAdoptedThread(0));

    t->moveToThread(t.data());

    return t.take();

}

void QAdoptedThread::run()

{

    // this function should never be called

    qFatal("QAdoptedThread::run(): Internal error, this implementation should never be called.");

}

#ifndef QT_NO_THREAD

/*

  QThreadPrivate

*/

QThreadPrivate::QThreadPrivate(QThreadData *d)

    : QObjectPrivate(), running(false), finished(false), terminated(false),

      stackSize(0), priority(QThread::InheritPriority), data(d)

{

#if defined (Q_OS_UNIX)

    thread_id = 0;

#elif defined (Q_WS_WIN)

    handle = 0;

    id = 0;

    waiters = 0;

#endif

#if defined (Q_WS_WIN) || defined (Q_OS_SYMBIAN)

    terminationEnabled = true;

    terminatePending = false;

#endif

    if (!data)

        data = new QThreadData;

}

QThreadPrivate::~QThreadPrivate()

{

    data->deref();

}

/*!

    \class QThread

    \brief The QThread class provides platform-independent threads.

    \ingroup thread

    A QThread represents a separate thread of control within the

    program; it shares data with all the other threads within the

    process but executes independently in the way that a separate

    program does on a multitasking operating system. Instead of

    starting in \c main(), QThreads begin executing in run().  By

    default, run() starts the event loop by calling exec() (see

    below). To create your own threads, subclass QThread and

    reimplement run(). For example:

    \snippet doc/src/snippets/code/src_corelib_thread_qthread.cpp 0

    This will create a QTcpSocket in the thread and then execute the

    thread's event loop. Use the start() method to begin execution.

    Execution ends when you return from run(), just as an application

    does when it leaves main(). QThread will notifiy you via a signal

    when the thread is started(), finished(), and terminated(), or

    you can use isFinished() and isRunning() to query the state of

    the thread. Use wait() to block until the thread has finished

    execution.

    Each thread gets its own stack from the operating system. The

    operating system also determines the default size of the stack.

    You can use setStackSize() to set a custom stack size.

    Each QThread can have its own event loop. You can start the event

    loop by calling exec(); you can stop it by calling exit() or

    quit(). Having an event loop in a thread makes it possible to

    connect signals from other threads to slots in this thread, using

    a mechanism called \l{Qt::QueuedConnection}{queued

    connections}. It also makes it possible to use classes that

    require the event loop, such as QTimer and QTcpSocket, in the

    thread. Note, however, that it is not possible to use any widget

    classes in the thread.

    In extreme cases, you may want to forcibly terminate() an

    executing thread. However, doing so is dangerous and discouraged.

    Please read the documentation for terminate() and

    setTerminationEnabled() for detailed information.

    The static functions currentThreadId() and currentThread() return

    identifiers for the currently executing thread. The former

    returns a platform specific ID for the thread; the latter returns

    a QThread pointer.

    QThread also provides platform independent sleep functions in

    varying resolutions. Use sleep() for full second resolution,

    msleep() for millisecond resolution, and usleep() for microsecond

    resolution.

    \sa {Thread Support in Qt}, QThreadStorage, QMutex, QSemaphore, QWaitCondition,

        {Mandelbrot Example}, {Semaphores Example}, {Wait Conditions Example}

*/

/*!

    \fn Qt::HANDLE QThread::currentThreadId()

    Returns the thread handle of the currently executing thread.

    \warning The handle returned by this function is used for internal

    purposes and should not be used in any application code.

    \warning On Windows, the returned value is a pseudo-handle for the

    current thread. It can't be used for numerical comparison. i.e.,

    this function returns the DWORD (Windows-Thread ID) returned by

    the Win32 function getCurrentThreadId(), not the HANDLE

    (Windows-Thread HANDLE) returned by the Win32 function

    getCurrentThread().

*/

/*!

    \fn int QThread::idealThreadCount()

    Returns the ideal number of threads that can be run on the system. This is done querying

    the number of processor cores, both real and logical, in the system. This function returns -1

    if the number of processor cores could not be detected.

*/

/*!

    \fn void QThread::yieldCurrentThread()

    Yields execution of the current thread to another runnable thread,

    if any. Note that the operating system decides to which thread to

    switch.

*/

/*!

    \fn void QThread::start(Priority priority)

    Begins execution of the thread by calling run(), which should be

    reimplemented in a QThread subclass to contain your code. The

    operating system will schedule the thread according to the \a

    priority parameter. If the thread is already running, this

    function does nothing.

    The effect of the \a priority parameter is dependent on the

    operating system's scheduling policy. In particular, the \a priority

    will be ignored on systems that do not support thread priorities

    (such as on Linux, see http://linux.die.net/man/2/sched_setscheduler

    for more details).

    \sa run(), terminate()

*/

/*!

    \fn void QThread::started()

    This signal is emitted when the thread starts executing.

    \sa finished(), terminated()

*/

/*!

    \fn void QThread::finished()

    This signal is emitted when the thread has finished executing.

    \sa started(), terminated()

*/

/*!

    \fn void QThread::terminated()

    This signal is emitted when the thread is terminated.

    \sa started(), finished()

*/

/*!

    \enum QThread::Priority

    This enum type indicates how the operating system should schedule

    newly created threads.

    \value IdlePriority scheduled only when no other threads are

           running.

    \value LowestPriority scheduled less often than LowPriority.

    \value LowPriority scheduled less often than NormalPriority.

    \value NormalPriority the default priority of the operating

           system.

    \value HighPriority scheduled more often than NormalPriority.

    \value HighestPriority scheduled more often than HighPriority.

    \value TimeCriticalPriority scheduled as often as possible.

    \value InheritPriority use the same priority as the creating

           thread. This is the default.

*/

/*!

    Returns a pointer to a QThread which represents the currently

    executing thread.

*/

QThread *QThread::currentThread()

{

    QThreadData *data = QThreadData::current();

    Q_ASSERT(data != 0);

    return data->thread;

}

/*!

    Constructs a new thread with the given \a parent. The thread does

    not begin executing until start() is called.

    \sa start()

*/

QThread::QThread(QObject *parent)

    : QObject(*(new QThreadPrivate), parent)

{

    Q_D(QThread);

    // fprintf(stderr, "QThreadData %p created for thread %p\n", d->data, this);

    d->data->thread = this;

}

/*! \internal

 */

QThread::QThread(QThreadPrivate &dd, QObject *parent)

    : QObject(dd, parent)

{

    Q_D(QThread);

    // fprintf(stderr, "QThreadData %p taken from private data for thread %p\n", d->data, this);

    d->data->thread = this;

}

/*!

    Destroys the thread.

    Note that deleting a QThread object will not stop the execution

    of the thread it represents. Deleting a running QThread (i.e.

    isFinished() returns false) will probably result in a program

    crash. You can wait() on a thread to make sure that it has

    finished.

*/

QThread::~QThread()

{

    Q_D(QThread);

    {

        QMutexLocker locker(&d->mutex);

        if (d->running && !d->finished)

            qWarning("QThread: Destroyed while thread is still running");

        d->data->thread = 0;

    }

}

/*!

    Returns true if the thread is finished; otherwise returns false.

    \sa isRunning()

*/

bool QThread::isFinished() const

{

    Q_D(const QThread);

    QMutexLocker locker(&d->mutex);

    return d->finished;

}

/*!

    Returns true if the thread is running; otherwise returns false.

    \sa isFinished()

*/

bool QThread::isRunning() const

{

    Q_D(const QThread);

    QMutexLocker locker(&d->mutex);

    return d->running;

}

/*!

    Sets the maximum stack size for the thread to \a stackSize. If \a

    stackSize is greater than zero, the maximum stack size is set to

    \a stackSize bytes, otherwise the maximum stack size is

    automatically determined by the operating system.

    \warning Most operating systems place minimum and maximum limits

    on thread stack sizes. The thread will fail to start if the stack

    size is outside these limits.

    \sa stackSize()

*/

void QThread::setStackSize(uint stackSize)

{

    Q_D(QThread);

    QMutexLocker locker(&d->mutex);

    Q_ASSERT_X(!d->running, "QThread::setStackSize",

               "cannot change stack size while the thread is running");

    d->stackSize = stackSize;

}

/*!

    Returns the maximum stack size for the thread (if set with

    setStackSize()); otherwise returns zero.

    \sa setStackSize()

*/

uint QThread::stackSize() const

{

    Q_D(const QThread);

    QMutexLocker locker(&d->mutex);

    return d->stackSize;

}

/*!

    Enters the event loop and waits until exit() is called, returning the value

    that was passed to exit(). The value returned is 0 if exit() is called via

    quit().

    It is necessary to call this function to start event handling.

    \sa quit(), exit()

*/

int QThread::exec()

{

    Q_D(QThread);

    QMutexLocker locker(&d->mutex);

    d->data->quitNow = false;

    QEventLoop eventLoop;

    locker.unlock();

    int returnCode = eventLoop.exec();

    return returnCode;

}

/*!

    Tells the thread's event loop to exit with a return code.

    After calling this function, the thread leaves the event loop and

    returns from the call to QEventLoop::exec(). The

    QEventLoop::exec() function returns \a returnCode.

    By convention, a \a returnCode of 0 means success, any non-zero value

    indicates an error.

    Note that unlike the C library function of the same name, this

    function \e does return to the caller -- it is event processing

    that stops.

    This function does nothing if the thread does not have an event

    loop.

    \sa quit() QEventLoop

*/

void QThread::exit(int returnCode)

{

    Q_D(QThread);

    QMutexLocker locker(&d->mutex);

    d->data->quitNow = true;

    for (int i = 0; i < d->data->eventLoops.size(); ++i) {

        QEventLoop *eventLoop = d->data->eventLoops.at(i);

        eventLoop->exit(returnCode);

    }

}

/*!

    Tells the thread's event loop to exit with return code 0 (success).

    Equivalent to calling QThread::exit(0).

    This function does nothing if the thread does not have an event

    loop.

    \sa exit() QEventLoop