5 懵逼了，rt_event_recv设置RT_WAITING_FOREVER却直接返回，recved居然是入参set值

发布于 2024-08-26 15:47:06 浏览：267 订阅该版

rt-thread版本4.1.1
在一个thread中使用rt_event_recv接收在中断中发出的event，

```c
if (rt_event_recv(&event, (FLAG(FB_OverCurrent) | FLAG(FB_ROverCurrent) | FLAG(FB_OverTemp) | FLAG(FB_Scram)),
					  RT_EVENT_FLAG_OR|RT_EVENT_FLAG_CLEAR,
					  RT_WAITING_FOREVER, &e) == RT_EOK)
```

收到一次正常`event（FLAG(FB_OverCurrent)）`后一直连续收到异常event，值为`（FLAG(FB_OverCurrent) | FLAG(FB_ROverCurrent) | FLAG(FB_OverTemp) | FLAG(FB_Scram)）`直到程序死掉，而此时`event->set`值其实际0，进入`rt_event_recv`调试发现走到了以下代码分支中：

```c
else
    {
        /* fill thread event info */
        thread->event_set  = set;
        thread->event_info = option;

/* put thread to suspended thread list */
        _ipc_list_suspend(&(event->parent.suspend_thread),
                            thread,
                            event->parent.parent.flag);

/* if there is a waiting timeout, active thread timer */
        if (timeout > 0)
        {
            /* reset the timeout of thread timer and start it */
            rt_timer_control(&(thread->thread_timer),
                             RT_TIMER_CTRL_SET_TIME,
                             &timeout);
            rt_timer_start(&(thread->thread_timer));
        }

/* enable interrupt */
        rt_hw_interrupt_enable(level);

/* do a schedule */
        rt_schedule();

if (thread->error != RT_EOK)
        {
            /* return error */
            return thread->error;
        }

/* received an event, disable interrupt to protect */
        level = rt_hw_interrupt_disable();

/* set received event */
        if (recved)
            *recved = thread->event_set;
    }
```
这里面开头`thread->event_set  = set`;
结尾`*recved = thread->event_set`;
等于是把入参`set`赋给`rt_event_recv`的接收值e了，为什么会有这样这样的操作？
想知道这段分支代码是在干嘛？
该如何debug我遇到的这问题？望大佬们赐教！

进一步到rt_schedule里发现
```c
    if (rt_thread_ready_priority_group != 0)
```
这个分支没进入就直接返回了，所以*recved直接就变成set的值了，仍需进一步排查。