1 files changed, 47 insertions, 28 deletions

diff --git a/src/corelib/thread/qthread_unix.cpp b/src/corelib/thread/qthread_unix.cpp
index 563c032db4..44487a2cc2 100644
--- a/src/corelib/thread/qthread_unix.cpp
+++ b/src/corelib/thread/qthread_unix.cpp
@@ -8,6 +8,7 @@
 
 #include <private/qcoreapplication_p.h>
 #include <private/qcore_unix_p.h>
+#include <private/qtools_p.h>
 
 #if defined(Q_OS_DARWIN)
 #  include <private/qeventdispatcher_cf_p.h>
@@ -19,7 +20,9 @@
 #  endif
 #endif
 
-#include <private/qeventdispatcher_unix_p.h>
+#if !defined(Q_OS_WASM)
+#  include <private/qeventdispatcher_unix_p.h>
+#endif
 
 #include "qthreadstorage.h"
 
@@ -70,6 +73,8 @@
 
 QT_BEGIN_NAMESPACE
 
+using namespace QtMiscUtils;
+
 #if QT_CONFIG(thread)
 
 static_assert(sizeof(pthread_t) <= sizeof(Qt::HANDLE));
@@ -186,8 +191,10 @@ QThreadData *QThreadData::current(bool createIfNecessary)
         data->deref();
         data->isAdopted = true;
         data->threadId.storeRelaxed(to_HANDLE(pthread_self()));
-        if (!QCoreApplicationPrivate::theMainThread.loadAcquire())
+        if (!QCoreApplicationPrivate::theMainThreadId.loadAcquire()) {
             QCoreApplicationPrivate::theMainThread.storeRelease(data->thread.loadRelaxed());
+            QCoreApplicationPrivate::theMainThreadId.storeRelaxed(data->threadId.loadRelaxed());
+        }
     }
     return data;
 }
@@ -234,12 +241,12 @@ QAbstractEventDispatcher *QThreadPrivate::createEventDispatcher(QThreadData *dat
 
 #if QT_CONFIG(thread)
 
-#if (defined(Q_OS_LINUX) || defined(Q_OS_MAC) || defined(Q_OS_QNX))
+#if (defined(Q_OS_LINUX) || defined(Q_OS_DARWIN) || 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)
+#  elif defined(Q_OS_DARWIN)
     pthread_setname_np(name);
 #  elif defined(Q_OS_QNX)
     pthread_setname_np(pthread_self(), name);
@@ -272,11 +279,19 @@ void terminate_on_exception(T &&t)
 
 void *QThreadPrivate::start(void *arg)
 {
-#if !defined(Q_OS_ANDROID)
+#ifdef PTHREAD_CANCEL_DISABLE
     pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, nullptr);
 #endif
-    pthread_cleanup_push(QThreadPrivate::finish, arg);
-
+#if !defined(Q_OS_QNX) && !defined(Q_OS_VXWORKS)
+    // On QNX, calling finish() from a thread_local destructor causes the C
+    // library to hang.
+    // On VxWorks, its pthread implementation fails on call to `pthead_setspecific` which is made
+    // by first QObject constructor during `finish()`. This causes call to QThread::current, since
+    // QObject doesn't have parent, and since the pthread is already removed, it tries to set
+    // QThreadData for current pthread key, which crashes.
+    static thread_local
+#endif
+            auto cleanup = qScopeGuard([=] { finish(arg); });
     terminate_on_exception([&] {
         QThread *thr = reinterpret_cast<QThread *>(arg);
         QThreadData *data = QThreadData::get2(thr);
@@ -301,7 +316,7 @@ void *QThreadPrivate::start(void *arg)
         data->ensureEventDispatcher();
         data->eventDispatcher.loadRelaxed()->startingUp();
 
-#if (defined(Q_OS_LINUX) || defined(Q_OS_MAC) || defined(Q_OS_QNX))
+#if (defined(Q_OS_LINUX) || defined(Q_OS_DARWIN) || 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
@@ -314,18 +329,14 @@ void *QThreadPrivate::start(void *arg)
 #endif
 
         emit thr->started(QThread::QPrivateSignal());
-#if !defined(Q_OS_ANDROID)
+#ifdef PTHREAD_CANCEL_DISABLE
         pthread_setcancelstate(PTHREAD_CANCEL_ENABLE, nullptr);
         pthread_testcancel();
 #endif
         thr->run();
     });
 
-    // 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);
-
+    // The qScopeGuard above call runs finish() below.
     return nullptr;
 }
 
@@ -342,6 +353,7 @@ void QThreadPrivate::finish(void *arg)
         void *data = &d->data->tls;
         locker.unlock();
         emit thr->finished(QThread::QPrivateSignal());
+        qCDebug(lcDeleteLater) << "Sending deferred delete events as part of finishing thread" << thr;
         QCoreApplication::sendPostedEvents(nullptr, QEvent::DeferredDelete);
         QThreadStorageData::finish((void **)data);
         locker.relock();
@@ -357,7 +369,7 @@ void QThreadPrivate::finish(void *arg)
 
         d->running = false;
         d->finished = true;
-        d->interruptionRequested = false;
+        d->interruptionRequested.store(false, std::memory_order_relaxed);
 
         d->isInFinish = false;
         d->data->threadId.storeRelaxed(nullptr);
@@ -488,31 +500,38 @@ void QThread::yieldCurrentThread()
 
 #endif // QT_CONFIG(thread)
 
-static timespec makeTimespec(std::chrono::nanoseconds nsecs)
+static void qt_nanosleep(timespec amount)
 {
-    using namespace std::chrono;
-    const seconds secs = duration_cast<seconds>(nsecs);
-    const nanoseconds frac = nsecs - secs;
-    struct timespec ts;
-    ts.tv_sec = secs.count();
-    ts.tv_nsec = frac.count();
-    return ts;
-}
+    // We'd like to use clock_nanosleep.
+    //
+    // But clock_nanosleep is from POSIX.1-2001 and both are *not*
+    // affected by clock changes when using relative sleeps, even for
+    // CLOCK_REALTIME.
+    //
+    // nanosleep is POSIX.1-1993
 
+    int r;
+    QT_EINTR_LOOP(r, nanosleep(&amount, &amount));
+}
 
 void QThread::sleep(unsigned long secs)
 {
-    qt_nanosleep(makeTimespec(std::chrono::seconds{secs}));
+    sleep(std::chrono::seconds{secs});
 }
 
 void QThread::msleep(unsigned long msecs)
 {
-    qt_nanosleep(makeTimespec(std::chrono::milliseconds{msecs}));
+    sleep(std::chrono::milliseconds{msecs});
 }
 
 void QThread::usleep(unsigned long usecs)
 {
-    qt_nanosleep(makeTimespec(std::chrono::microseconds{usecs}));
+    sleep(std::chrono::microseconds{usecs});
+}
+
+void QThread::sleep(std::chrono::nanoseconds nsec)
+{
+    qt_nanosleep(durationToTimespec(nsec));
 }
 
 #if QT_CONFIG(thread)
@@ -627,7 +646,7 @@ void QThread::start(Priority priority)
     d->finished = false;
     d->returnCode = 0;
     d->exited = false;
-    d->interruptionRequested = false;
+    d->interruptionRequested.store(false, std::memory_order_relaxed);
 
     pthread_attr_t attr;
     pthread_attr_init(&attr);