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path: root/src/corelib/thread/qthread_unix.cpp
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/****************************************************************************
**
** Copyright (C) 2016 The Qt Company Ltd.
** Copyright (C) 2016 Intel Corporation.
** Contact: https://www.qt.io/licensing/
**
** This file is part of the QtCore module of the Qt Toolkit.
**
** $QT_BEGIN_LICENSE:LGPL$
** Commercial License Usage
** Licensees holding valid commercial Qt licenses may use this file in
** accordance with the commercial license agreement provided with the
** Software or, alternatively, in accordance with the terms contained in
** a written agreement between you and The Qt Company. For licensing terms
** and conditions see https://www.qt.io/terms-conditions. For further
** information use the contact form at https://www.qt.io/contact-us.
**
** GNU Lesser General Public License Usage
** Alternatively, this file may be used under the terms of the GNU Lesser
** General Public License version 3 as published by the Free Software
** Foundation and appearing in the file LICENSE.LGPL3 included in the
** packaging of this file. Please review the following information to
** ensure the GNU Lesser General Public License version 3 requirements
** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
**
** GNU General Public License Usage
** Alternatively, this file may be used under the terms of the GNU
** General Public License version 2.0 or (at your option) the GNU General
** Public license version 3 or any later version approved by the KDE Free
** Qt Foundation. The licenses are as published by the Free Software
** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
** included in the packaging of this file. Please review the following
** information to ensure the GNU General Public License requirements will
** be met: https://www.gnu.org/licenses/gpl-2.0.html and
** https://www.gnu.org/licenses/gpl-3.0.html.
**
** $QT_END_LICENSE$
**
****************************************************************************/

#include "qthread.h"

#include "qplatformdefs.h"

#include <private/qcoreapplication_p.h>
#include <private/qcore_unix_p.h>

#if defined(Q_OS_DARWIN)
#  include <private/qeventdispatcher_cf_p.h>
#else
#  if !defined(QT_NO_GLIB)
#    include "../kernel/qeventdispatcher_glib_p.h"
#  endif
#endif

#include <private/qeventdispatcher_unix_p.h>

#include "qthreadstorage.h"

#include "qthread_p.h"

#include "qdebug.h"

#ifdef __GLIBCXX__
#include <cxxabi.h>
#endif

#include <sched.h>
#include <errno.h>

#ifdef Q_OS_BSD4
#include <sys/sysctl.h>
#endif
#ifdef Q_OS_VXWORKS
#  if (_WRS_VXWORKS_MAJOR > 6) || ((_WRS_VXWORKS_MAJOR == 6) && (_WRS_VXWORKS_MINOR >= 6))
#    include <vxCpuLib.h>
#    include <cpuset.h>
#    define QT_VXWORKS_HAS_CPUSET
#  endif
#endif

#ifdef Q_OS_HPUX
#include <sys/pstat.h>
#endif

#if defined(Q_OS_LINUX) && !defined(QT_LINUXBASE)
#include <sys/prctl.h>
#endif

#if defined(Q_OS_LINUX) && !defined(SCHED_IDLE)
// from linux/sched.h
# define SCHED_IDLE    5
#endif

#if defined(Q_OS_DARWIN) || !defined(Q_OS_ANDROID) && !defined(Q_OS_OPENBSD) && defined(_POSIX_THREAD_PRIORITY_SCHEDULING) && (_POSIX_THREAD_PRIORITY_SCHEDULING-0 >= 0)
#define QT_HAS_THREAD_PRIORITY_SCHEDULING
#endif

#if defined(Q_OS_QNX)
#include <sys/neutrino.h>
#endif

QT_BEGIN_NAMESPACE

#if QT_CONFIG(thread)

Q_STATIC_ASSERT(sizeof(pthread_t) <= sizeof(Qt::HANDLE));

enum { ThreadPriorityResetFlag = 0x80000000 };


static thread_local QThreadData *currentThreadData = nullptr;

static pthread_once_t current_thread_data_once = PTHREAD_ONCE_INIT;
static pthread_key_t current_thread_data_key;

static void destroy_current_thread_data(void *p)
{
#if defined(Q_OS_VXWORKS)
    // Calling setspecific(..., 0) sets the value to 0 for ALL threads.
    // The 'set to 1' workaround adds a bit of an overhead though,
    // since this function is called twice now.
    if (p == (void *)1)
        return;
#endif
    // POSIX says the value in our key is set to zero before calling
    // this destructor function, so we need to set it back to the
    // right value...
    pthread_setspecific(current_thread_data_key, p);
    QThreadData *data = static_cast<QThreadData *>(p);
    if (data->isAdopted) {
        QThread *thread = data->thread.loadAcquire();
        Q_ASSERT(thread);
        QThreadPrivate *thread_p = static_cast<QThreadPrivate *>(QObjectPrivate::get(thread));
        Q_ASSERT(!thread_p->finished);
        thread_p->finish(thread);
    }
    data->deref();

    // ... but we must reset it to zero before returning so we aren't
    // called again (POSIX allows implementations to call destructor
    // functions repeatedly until all values are zero)
    pthread_setspecific(current_thread_data_key,
#if defined(Q_OS_VXWORKS)
                                                 (void *)1);
#else
                                                 nullptr);
#endif
}

static void create_current_thread_data_key()
{
    pthread_key_create(&current_thread_data_key, destroy_current_thread_data);
}

static void destroy_current_thread_data_key()
{
    pthread_once(&current_thread_data_once, create_current_thread_data_key);
    pthread_key_delete(current_thread_data_key);

    // Reset current_thread_data_once in case we end up recreating
    // the thread-data in the rare case of QObject construction
    // after destroying the QThreadData.
    pthread_once_t pthread_once_init = PTHREAD_ONCE_INIT;
    current_thread_data_once = pthread_once_init;
}
Q_DESTRUCTOR_FUNCTION(destroy_current_thread_data_key)


// Utility functions for getting, setting and clearing thread specific data.
static QThreadData *get_thread_data()
{
    return currentThreadData;
}

static void set_thread_data(QThreadData *data)
{
    currentThreadData = data;
    pthread_once(&current_thread_data_once, create_current_thread_data_key);
    pthread_setspecific(current_thread_data_key, data);
}

static void clear_thread_data()
{
    currentThreadData = nullptr;
    pthread_setspecific(current_thread_data_key, nullptr);
}

template <typename T>
static typename std::enable_if<QTypeInfo<T>::isIntegral, Qt::HANDLE>::type to_HANDLE(T id)
{
    return reinterpret_cast<Qt::HANDLE>(static_cast<intptr_t>(id));
}

template <typename T>
static typename std::enable_if<QTypeInfo<T>::isIntegral, T>::type from_HANDLE(Qt::HANDLE id)
{
    return static_cast<T>(reinterpret_cast<intptr_t>(id));
}

template <typename T>
static typename std::enable_if<QTypeInfo<T>::isPointer, Qt::HANDLE>::type to_HANDLE(T id)
{
    return id;
}

template <typename T>
static typename std::enable_if<QTypeInfo<T>::isPointer, T>::type from_HANDLE(Qt::HANDLE id)
{
    return static_cast<T>(id);
}

void QThreadData::clearCurrentThreadData()
{
    clear_thread_data();
}

QThreadData *QThreadData::current(bool createIfNecessary)
{
    QThreadData *data = get_thread_data();
    if (!data && createIfNecessary) {
        data = new QThreadData;
        QT_TRY {
            set_thread_data(data);
            data->thread = new QAdoptedThread(data);
        } QT_CATCH(...) {
            clear_thread_data();
            data->deref();
            data = nullptr;
            QT_RETHROW;
        }
        data->deref();
        data->isAdopted = true;
        data->threadId.storeRelaxed(to_HANDLE(pthread_self()));
        if (!QCoreApplicationPrivate::theMainThread.loadAcquire())
            QCoreApplicationPrivate::theMainThread.storeRelease(data->thread.loadRelaxed());
    }
    return data;
}


void QAdoptedThread::init()
{
}

/*
   QThreadPrivate
*/

extern "C" {
typedef void*(*QtThreadCallback)(void*);
}

#endif // QT_CONFIG(thread)

QAbstractEventDispatcher *QThreadPrivate::createEventDispatcher(QThreadData *data)
{
    Q_UNUSED(data);
#if defined(Q_OS_DARWIN)
    bool ok = false;
    int value = qEnvironmentVariableIntValue("QT_EVENT_DISPATCHER_CORE_FOUNDATION", &ok);
    if (ok && value > 0)
        return new QEventDispatcherCoreFoundation;
    else
        return new QEventDispatcherUNIX;
#elif !defined(QT_NO_GLIB)
    const bool isQtMainThread = data->thread.loadAcquire() == QCoreApplicationPrivate::mainThread();
    if (qEnvironmentVariableIsEmpty("QT_NO_GLIB")
        && (isQtMainThread || qEnvironmentVariableIsEmpty("QT_NO_THREADED_GLIB"))
        && QEventDispatcherGlib::versionSupported())
        return new QEventDispatcherGlib;
    else
        return new QEventDispatcherUNIX;
#else
    return new QEventDispatcherUNIX;
#endif
}

#if QT_CONFIG(thread)

#if (defined(Q_OS_LINUX) || defined(Q_OS_MAC) || defined(Q_OS_QNX))
static void setCurrentThreadName(const char *name)
{
#  if defined(Q_OS_LINUX) && !defined(QT_LINUXBASE)
    prctl(PR_SET_NAME, (unsigned long)name, 0, 0, 0);
#  elif defined(Q_OS_MAC)
    pthread_setname_np(name);
#  elif defined(Q_OS_QNX)
    pthread_setname_np(pthread_self(), name);
#  endif
}
#endif

void *QThreadPrivate::start(void *arg)
{
#if !defined(Q_OS_ANDROID)
    pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, nullptr);
#endif
    pthread_cleanup_push(QThreadPrivate::finish, arg);

#ifndef QT_NO_EXCEPTIONS
    try
#endif
    {
        QThread *thr = reinterpret_cast<QThread *>(arg);
        QThreadData *data = QThreadData::get2(thr);

        {
            QMutexLocker locker(&thr->d_func()->mutex);

            // do we need to reset the thread priority?
            if (int(thr->d_func()->priority) & ThreadPriorityResetFlag) {
                thr->d_func()->setPriority(QThread::Priority(thr->d_func()->priority & ~ThreadPriorityResetFlag));
            }

            data->threadId.storeRelaxed(to_HANDLE(pthread_self()));
            set_thread_data(data);

            data->ref();
            data->quitNow = thr->d_func()->exited;
        }

        data->ensureEventDispatcher();

#if (defined(Q_OS_LINUX) || defined(Q_OS_MAC) || defined(Q_OS_QNX))
        {
            // Sets the name of the current thread. We can only do this
            // when the thread is starting, as we don't have a cross
            // platform way of setting the name of an arbitrary thread.
            if (Q_LIKELY(thr->objectName().isEmpty()))
                setCurrentThreadName(thr->metaObject()->className());
            else
                setCurrentThreadName(thr->objectName().toLocal8Bit());
        }
#endif

        emit thr->started(QThread::QPrivateSignal());
#if !defined(Q_OS_ANDROID)
        pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, nullptr);
        pthread_testcancel();
#endif
        thr->run();
    }
#ifndef QT_NO_EXCEPTIONS
#ifdef __GLIBCXX__
    // POSIX thread cancellation under glibc is implemented by throwing an exception
    // of this type. Do what libstdc++ is doing and handle it specially in order not to
    // abort the application if user's code calls a cancellation function.
    catch (const abi::__forced_unwind &) {
        throw;
    }
#endif // __GLIBCXX__
    catch (...) {
        qTerminate();
    }
#endif // QT_NO_EXCEPTIONS

    // This pop runs finish() below. It's outside the try/catch (and has its
    // own try/catch) to prevent finish() to be run in case an exception is
    // thrown.
    pthread_cleanup_pop(1);

    return nullptr;
}

void QThreadPrivate::finish(void *arg)
{
#ifndef QT_NO_EXCEPTIONS
    try
#endif
    {
        QThread *thr = reinterpret_cast<QThread *>(arg);
        QThreadPrivate *d = thr->d_func();

        QMutexLocker locker(&d->mutex);

        d->isInFinish = true;
        d->priority = QThread::InheritPriority;
        void *data = &d->data->tls;
        locker.unlock();
        emit thr->finished(QThread::QPrivateSignal());
        QCoreApplication::sendPostedEvents(nullptr, QEvent::DeferredDelete);
        QThreadStorageData::finish((void **)data);
        locker.relock();

        QAbstractEventDispatcher *eventDispatcher = d->data->eventDispatcher.loadRelaxed();
        if (eventDispatcher) {
            d->data->eventDispatcher = nullptr;
            locker.unlock();
            eventDispatcher->closingDown();
            delete eventDispatcher;
            locker.relock();
        }

        d->running = false;
        d->finished = true;
        d->interruptionRequested = false;

        d->isInFinish = false;
        d->thread_done.wakeAll();
    }
#ifndef QT_NO_EXCEPTIONS
#ifdef __GLIBCXX__
    // POSIX thread cancellation under glibc is implemented by throwing an exception
    // of this type. Do what libstdc++ is doing and handle it specially in order not to
    // abort the application if user's code calls a cancellation function.
    catch (const abi::__forced_unwind &) {
        throw;
    }
#endif // __GLIBCXX__
    catch (...) {
        qTerminate();
    }
#endif // QT_NO_EXCEPTIONS
}


/**************************************************************************
 ** QThread
 *************************************************************************/

/*
    Since each thread is guaranteed to have its own copy of
    currenThreadData, the address is guaranteed to be unique for each
    running thread (but likely to be reused for newly started threads).

    CI tests fails on ARM architectures if we try to use the assembler,
    or the address of the thread_local (even with a recent gcc version), so
    stick to the pthread version there. The assembler would be

    // http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0344k/Babeihid.html
    asm volatile ("mrc p15, 0, %0, c13, c0, 3" : "=r" (tid));

    and

    // see glibc/sysdeps/aarch64/nptl/tls.h
    asm volatile ("mrs %0, tpidr_el0" : "=r" (tid));

    for 32 and 64bit versions, respectively.
*/
Qt::HANDLE QThread::currentThreadIdImpl() noexcept
{
#if defined(Q_PROCESSOR_ARM)
    return to_HANDLE(pthread_self());
#else
    return &currentThreadData;
#endif
}

#if defined(QT_LINUXBASE) && !defined(_SC_NPROCESSORS_ONLN)
// LSB doesn't define _SC_NPROCESSORS_ONLN.
#  define _SC_NPROCESSORS_ONLN 84
#endif

#ifdef Q_OS_WASM
int QThreadPrivate::idealThreadCount = 1;
#endif

int QThread::idealThreadCount() noexcept
{
    int cores = 1;

#if defined(Q_OS_HPUX)
    // HP-UX
    struct pst_dynamic psd;
    if (pstat_getdynamic(&psd, sizeof(psd), 1, 0) == -1) {
        perror("pstat_getdynamic");
    } else {
        cores = (int)psd.psd_proc_cnt;
    }
#elif defined(Q_OS_BSD4)
    // FreeBSD, OpenBSD, NetBSD, BSD/OS, OS X, iOS
    size_t len = sizeof(cores);
    int mib[2];
    mib[0] = CTL_HW;
    mib[1] = HW_NCPU;
    if (sysctl(mib, 2, &cores, &len, NULL, 0) != 0) {
        perror("sysctl");
    }
#elif defined(Q_OS_INTEGRITY)
#if (__INTEGRITY_MAJOR_VERSION >= 10)
    // Integrity V10+ does support multicore CPUs
    Value processorCount;
    if (GetProcessorCount(CurrentTask(), &processorCount) == 0)
        cores = processorCount;
    else
#endif
    // as of aug 2008 Integrity only supports one single core CPU
    cores = 1;
#elif defined(Q_OS_VXWORKS)
    // VxWorks
#  if defined(QT_VXWORKS_HAS_CPUSET)
    cpuset_t cpus = vxCpuEnabledGet();
    cores = 0;

    // 128 cores should be enough for everyone ;)
    for (int i = 0; i < 128 && !CPUSET_ISZERO(cpus); ++i) {
        if (CPUSET_ISSET(cpus, i)) {
            CPUSET_CLR(cpus, i);
            cores++;
        }
    }
#  else
    // as of aug 2008 VxWorks < 6.6 only supports one single core CPU
    cores = 1;
#  endif
#elif defined(Q_OS_WASM)
    cores = QThreadPrivate::idealThreadCount;
#else
    // the rest: Linux, Solaris, AIX, Tru64
    cores = (int)sysconf(_SC_NPROCESSORS_ONLN);
    if (cores == -1)
        return 1;
#endif
    return cores;
}

void QThread::yieldCurrentThread()
{
    sched_yield();
}

#endif // QT_CONFIG(thread)

static timespec makeTimespec(time_t secs, long nsecs)
{
    struct timespec ts;
    ts.tv_sec = secs;
    ts.tv_nsec = nsecs;
    return ts;
}

void QThread::sleep(unsigned long secs)
{
    qt_nanosleep(makeTimespec(secs, 0));
}

void QThread::msleep(unsigned long msecs)
{
    qt_nanosleep(makeTimespec(msecs / 1000, msecs % 1000 * 1000 * 1000));
}

void QThread::usleep(unsigned long usecs)
{
    qt_nanosleep(makeTimespec(usecs / 1000 / 1000, usecs % (1000*1000) * 1000));
}

#if QT_CONFIG(thread)

#ifdef QT_HAS_THREAD_PRIORITY_SCHEDULING
#if defined(Q_OS_QNX)
static bool calculateUnixPriority(int priority, int *sched_policy, int *sched_priority)
{
    // On QNX, NormalPriority is mapped to 10.  A QNX system could use a value different
    // than 10 for the "normal" priority but it's difficult to achieve this so we'll
    // assume that no one has ever created such a system.  This makes the mapping from
    // Qt priorities to QNX priorities lopsided.   There's usually more space available
    // to map into above the "normal" priority than below it.  QNX also has a privileged
    // priority range (for threads that assist the kernel).  We'll assume that no Qt
    // thread needs to use priorities in that range.
    int priority_norm = 10;
    // _sched_info::priority_priv isn't documented.  You'd think that it's the start of the
    // privileged priority range but it's actually the end of the unpriviledged range.
    struct _sched_info info;
    if (SchedInfo_r(0, *sched_policy, &info) != EOK)
        return false;

    if (priority == QThread::IdlePriority) {
        *sched_priority = info.priority_min;
        return true;
    }

    if (priority_norm < info.priority_min)
        priority_norm = info.priority_min;
    if (priority_norm > info.priority_priv)
        priority_norm = info.priority_priv;

    int to_min, to_max;
    int from_min, from_max;
    int prio;
    if (priority < QThread::NormalPriority) {
        to_min = info.priority_min;
        to_max = priority_norm;
        from_min = QThread::LowestPriority;
        from_max = QThread::NormalPriority;
    } else {
        to_min = priority_norm;
        to_max = info.priority_priv;
        from_min = QThread::NormalPriority;
        from_max = QThread::TimeCriticalPriority;
    }

    prio = ((priority - from_min) * (to_max - to_min)) / (from_max - from_min) + to_min;
    prio = qBound(to_min, prio, to_max);

    *sched_priority = prio;
    return true;
}
#else
// Does some magic and calculate the Unix scheduler priorities
// sched_policy is IN/OUT: it must be set to a valid policy before calling this function
// sched_priority is OUT only
static bool calculateUnixPriority(int priority, int *sched_policy, int *sched_priority)
{
#ifdef SCHED_IDLE
    if (priority == QThread::IdlePriority) {
        *sched_policy = SCHED_IDLE;
        *sched_priority = 0;
        return true;
    }
    const int lowestPriority = QThread::LowestPriority;
#else
    const int lowestPriority = QThread::IdlePriority;
#endif
    const int highestPriority = QThread::TimeCriticalPriority;

    int prio_min;
    int prio_max;
#if defined(Q_OS_VXWORKS) && defined(VXWORKS_DKM)
    // for other scheduling policies than SCHED_RR or SCHED_FIFO
    prio_min = SCHED_FIFO_LOW_PRI;
    prio_max = SCHED_FIFO_HIGH_PRI;

    if ((*sched_policy == SCHED_RR) || (*sched_policy == SCHED_FIFO))
#endif
    {
    prio_min = sched_get_priority_min(*sched_policy);
    prio_max = sched_get_priority_max(*sched_policy);
    }

    if (prio_min == -1 || prio_max == -1)
        return false;

    int prio;
    // crudely scale our priority enum values to the prio_min/prio_max
    prio = ((priority - lowestPriority) * (prio_max - prio_min) / highestPriority) + prio_min;
    prio = qMax(prio_min, qMin(prio_max, prio));

    *sched_priority = prio;
    return true;
}
#endif
#endif

void QThread::start(Priority priority)
{
    Q_D(QThread);
    QMutexLocker locker(&d->mutex);

    if (d->isInFinish)
        d->thread_done.wait(locker.mutex());

    if (d->running)
        return;

    d->running = true;
    d->finished = false;
    d->returnCode = 0;
    d->exited = false;
    d->interruptionRequested = false;

    pthread_attr_t attr;
    pthread_attr_init(&attr);
    pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED);

    d->priority = priority;

#if defined(QT_HAS_THREAD_PRIORITY_SCHEDULING)
    switch (priority) {
    case InheritPriority:
        {
            pthread_attr_setinheritsched(&attr, PTHREAD_INHERIT_SCHED);
            break;
        }

    default:
        {
            int sched_policy;
            if (pthread_attr_getschedpolicy(&attr, &sched_policy) != 0) {
                // failed to get the scheduling policy, don't bother
                // setting the priority
                qWarning("QThread::start: Cannot determine default scheduler policy");
                break;
            }

            int prio;
            if (!calculateUnixPriority(priority, &sched_policy, &prio)) {
                // failed to get the scheduling parameters, don't
                // bother setting the priority
                qWarning("QThread::start: Cannot determine scheduler priority range");
                break;
            }

            sched_param sp;
            sp.sched_priority = prio;

            if (pthread_attr_setinheritsched(&attr, PTHREAD_EXPLICIT_SCHED) != 0
                || pthread_attr_setschedpolicy(&attr, sched_policy) != 0
                || pthread_attr_setschedparam(&attr, &sp) != 0) {
                // could not set scheduling hints, fallback to inheriting them
                // we'll try again from inside the thread
                pthread_attr_setinheritsched(&attr, PTHREAD_INHERIT_SCHED);
                d->priority = Priority(priority | ThreadPriorityResetFlag);
            }
            break;
        }
    }
#endif // QT_HAS_THREAD_PRIORITY_SCHEDULING


    if (d->stackSize > 0) {
#if defined(_POSIX_THREAD_ATTR_STACKSIZE) && (_POSIX_THREAD_ATTR_STACKSIZE-0 > 0)
        int code = pthread_attr_setstacksize(&attr, d->stackSize);
#else
        int code = ENOSYS; // stack size not supported, automatically fail
#endif // _POSIX_THREAD_ATTR_STACKSIZE

        if (code) {
            qErrnoWarning(code, "QThread::start: Thread stack size error");

            // we failed to set the stacksize, and as the documentation states,
            // the thread will fail to run...
            d->running = false;
            d->finished = false;
            return;
        }
    }

#ifdef Q_OS_INTEGRITY
    if (Q_LIKELY(objectName().isEmpty()))
        pthread_attr_setthreadname(&attr, metaObject()->className());
    else
        pthread_attr_setthreadname(&attr, objectName().toLocal8Bit());
#endif
    pthread_t threadId;
    int code = pthread_create(&threadId, &attr, QThreadPrivate::start, this);
    if (code == EPERM) {
        // caller does not have permission to set the scheduling
        // parameters/policy
#if defined(QT_HAS_THREAD_PRIORITY_SCHEDULING)
        pthread_attr_setinheritsched(&attr, PTHREAD_INHERIT_SCHED);
#endif
        code = pthread_create(&threadId, &attr, QThreadPrivate::start, this);
    }
    d->data->threadId.storeRelaxed(to_HANDLE(threadId));

    pthread_attr_destroy(&attr);

    if (code) {
        qErrnoWarning(code, "QThread::start: Thread creation error");

        d->running = false;
        d->finished = false;
        d->data->threadId.storeRelaxed(nullptr);
    }
}

void QThread::terminate()
{
#if !defined(Q_OS_ANDROID)
    Q_D(QThread);
    QMutexLocker locker(&d->mutex);

    if (!d->data->threadId.loadRelaxed())
        return;

    int code = pthread_cancel(from_HANDLE<pthread_t>(d->data->threadId.loadRelaxed()));
    if (code) {
        qErrnoWarning(code, "QThread::start: Thread termination error");
    }
#endif
}

bool QThread::wait(QDeadlineTimer deadline)
{
    Q_D(QThread);
    QMutexLocker locker(&d->mutex);

    if (from_HANDLE<pthread_t>(d->data->threadId.loadRelaxed()) == pthread_self()) {
        qWarning("QThread::wait: Thread tried to wait on itself");
        return false;
    }

    if (d->finished || !d->running)
        return true;

    while (d->running) {
        if (!d->thread_done.wait(locker.mutex(), deadline))
            return false;
    }
    return true;
}

void QThread::setTerminationEnabled(bool enabled)
{
    QThread *thr = currentThread();
    Q_ASSERT_X(thr != nullptr, "QThread::setTerminationEnabled()",
               "Current thread was not started with QThread.");

    Q_UNUSED(thr)
#if defined(Q_OS_ANDROID)
    Q_UNUSED(enabled);
#else
    pthread_setcancelstate(enabled ? PTHREAD_CANCEL_ENABLE : PTHREAD_CANCEL_DISABLE, nullptr);
    if (enabled)
        pthread_testcancel();
#endif
}

// Caller must lock the mutex
void QThreadPrivate::setPriority(QThread::Priority threadPriority)
{
    priority = threadPriority;

    // copied from start() with a few modifications:

#ifdef QT_HAS_THREAD_PRIORITY_SCHEDULING
    int sched_policy;
    sched_param param;

    if (pthread_getschedparam(from_HANDLE<pthread_t>(data->threadId.loadRelaxed()), &sched_policy, &param) != 0) {
        // failed to get the scheduling policy, don't bother setting
        // the priority
        qWarning("QThread::setPriority: Cannot get scheduler parameters");
        return;
    }

    int prio;
    if (!calculateUnixPriority(priority, &sched_policy, &prio)) {
        // failed to get the scheduling parameters, don't
        // bother setting the priority
        qWarning("QThread::setPriority: Cannot determine scheduler priority range");
        return;
    }

    param.sched_priority = prio;
    int status = pthread_setschedparam(from_HANDLE<pthread_t>(data->threadId.loadRelaxed()), sched_policy, &param);

# ifdef SCHED_IDLE
    // were we trying to set to idle priority and failed?
    if (status == -1 && sched_policy == SCHED_IDLE && errno == EINVAL) {
        // reset to lowest priority possible
        pthread_getschedparam(from_HANDLE<pthread_t>(data->threadId.loadRelaxed()), &sched_policy, &param);
        param.sched_priority = sched_get_priority_min(sched_policy);
        pthread_setschedparam(from_HANDLE<pthread_t>(data->threadId.loadRelaxed()), sched_policy, &param);
    }
# else
    Q_UNUSED(status);
# endif // SCHED_IDLE
#endif
}

#endif // QT_CONFIG(thread)

QT_END_NAMESPACE