qatomic_sh.cpp

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#include <QtCore/qglobal.h>

#include <unistd.h>
#ifdef _POSIX_PRIORITY_SCHEDULING
# include <sched.h>
#endif
#include <time.h>

QT_BEGIN_NAMESPACE

QT_USE_NAMESPACE

Q_CORE_EXPORT volatile char qt_atomic_lock = 0;

Q_CORE_EXPORT void qt_atomic_yield(int *count)
{
#ifdef _POSIX_PRIORITY_SCHEDULING
    if((*count)++ < 50) {
        sched_yield();
    } else
#endif
    {
        struct timespec tm;
        tm.tv_sec = 0;
        tm.tv_nsec = 2000001;
        nanosleep(&tm, NULL);
        *count = 0;
    }
}

QT_END_NAMESPACE