函数rt_timer_init 调用rt_object_init函数赋值参数问题

发布于 2022-11-15 16:10:56 浏览：400 订阅该版

RT-Thread Nano版 Version 3.1.5
一、在tiimer.c里的timer初始化通过函数 rt_timer_init 函数实现，代码如下：

```c
void rt_timer_init(rt_timer_t  timer,
                   const char *name,
                   void (*timeout)(void *parameter),
                   void       *parameter,
                   rt_tick_t   time,
                   rt_uint8_t  flag)
{
    /* timer check */
    RT_ASSERT(timer != RT_NULL);

/* timer object initialization */
    rt_object_init((rt_object_t)timer, RT_Object_Class_Timer, name);

_rt_timer_init(timer, timeout, parameter, time, flag);
}
```
**在函数里调用了对象初始化函数 rt_object_init ，赋予的第一个参数为(rt_object_t)timer 存在问题。**
首先，rt_object_t的定义如下：

```c
struct rt_object
{
    char       name[RT_NAME_MAX];                       /**< name of kernel object */
    rt_uint8_t type;                                    /**< type of kernel object */
    rt_uint8_t flag;                                    /**< flag of kernel object */

rt_list_t  list;                                    /**< list node of kernel object */
};
typedef struct rt_object *rt_object_t;                  /**< Type for kernel objects. */
```
其次，timer通过rt_timer_t定义，而rt_timer_t的定义如下：

```c
struct rt_timer
{
    struct rt_object parent;                            /**< inherit from rt_object */

rt_list_t        row[RT_TIMER_SKIP_LIST_LEVEL];

void (*timeout_func)(void *parameter);              /**< timeout function */
    void            *parameter;                         /**< timeout function's parameter */

rt_tick_t        init_tick;                         /**< timer timeout tick */
    rt_tick_t        timeout_tick;                      /**< timeout tick */
};
typedef struct rt_timer *rt_timer_t;
```
因此，调用 rt_object_init 函数的正确赋值如下：

```c
    /* timer object initialization */
    rt_object_init(&(timer->parent), RT_Object_Class_Timer, name);
```