Qt源码分析--QThread(5)

最新推荐文章于 2025-10-09 12:07:33 发布

原创

最新推荐文章于 2025-10-09 12:07:33 发布 · 2k 阅读

1 ·

CC 4.0 BY-SA版权

文章标签：

#qt #c++ #开发语言

本文详细介绍了QThread类的几个关键函数，包括设置线程优先级、堆栈大小、启用/禁用终止以及线程等待等。这些函数在多线程编程中用于管理和同步线程，确保线程安全和高效运行。同时，代码展示了如何处理错误情况，如尝试在未运行的线程上设置优先级或改变堆栈大小。

1.void setPriority(Priority priority);

void QThread::setPriority(Priority priority)
{
    Q_D(QThread);
    QMutexLocker locker(&d->mutex);
    if (!d->running) {
        qWarning("QThread::setPriority: Cannot set priority, thread is not running");
        return;
    }
    d->setPriority(priority);
}

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 faile