函数rt_timer_init是如何调用rt_object_init赋值参数的呢

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：

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：

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：

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：

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