rt-thread-official/examples/kernel/semaphore_dynamic.c

132 lines
2.9 KiB
C
Raw Blame History

This file contains ambiguous Unicode characters

This file contains Unicode characters that might be confused with other characters. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/*
* 程序清单:动态信号量
*
* 这个例子中将创建一个动态信号量初始值为0 )及一个动态线程,在这个动态线程中
* 将试图采用超时方式去持有信号量,应该超时返回。然后这个线程释放一次信号量,并
* 在后面继续采用永久等待方式去持有信号量, 成功获得信号量后返回。
*/
#include <rtthread.h>
#include "tc_comm.h"
/* 指向线程控制块的指针 */
static rt_thread_t tid = RT_NULL;
/* 指向信号量的指针 */
static rt_sem_t sem = RT_NULL;
/* 线程入口 */
static void thread_entry(void* parameter)
{
rt_err_t result;
rt_tick_t tick;
/* 获得当前的OS Tick */
tick = rt_tick_get();
/* 试图持有一个信号量如果10个OS Tick依然没拿到则超时返回 */
result = rt_sem_take(sem, 10);
if (result == -RT_ETIMEOUT)
{
/* 判断是否刚好过去10个OS Tick */
if (rt_tick_get() - tick != 10)
{
/* 如果失败,则测试失败 */
tc_done(TC_STAT_FAILED);
rt_sem_delete(sem);
return;
}
rt_kprintf("take semaphore timeout\n");
}
else
{
/* 因为并没释放信号量,应该是超时返回,否则测试失败 */
tc_done(TC_STAT_FAILED);
rt_sem_delete(sem);
return;
}
/* 释放一次信号量 */
rt_sem_release(sem);
/* 继续持有信号量,并永远等待直到持有到信号量 */
result = rt_sem_take(sem, RT_WAITING_FOREVER);
if (result != RT_EOK)
{
/* 返回不正确,测试失败 */
tc_done(TC_STAT_FAILED);
rt_sem_delete(sem);
return;
}
/* 测试成功 */
tc_done(TC_STAT_PASSED);
/* 删除信号量 */
rt_sem_delete(sem);
}
int semaphore_dynamic_init()
{
/* 创建一个信号量初始值是0 */
sem = rt_sem_create("sem", 0, RT_IPC_FLAG_FIFO);
if (sem == RT_NULL)
{
tc_stat(TC_STAT_END | TC_STAT_FAILED);
return 0;
}
/* 创建线程 */
tid = rt_thread_create("thread",
thread_entry, RT_NULL, /* 线程入口是thread_entry, 入口参数是RT_NULL */
THREAD_STACK_SIZE, THREAD_PRIORITY, THREAD_TIMESLICE);
if (tid != RT_NULL)
rt_thread_startup(tid);
else
tc_stat(TC_STAT_END | TC_STAT_FAILED);
return 0;
}
#ifdef RT_USING_TC
static void _tc_cleanup()
{
/* 调度器上锁,上锁后,将不再切换到其他线程,仅响应中断 */
rt_enter_critical();
if (sem)
{
rt_sem_delete(sem);
sem = RT_NULL;
}
/* 删除线程 */
if (tid != RT_NULL && tid->stat != RT_THREAD_CLOSE)
{
rt_thread_delete(tid);
}
/* 调度器解锁 */
rt_exit_critical();
/* 设置TestCase状态 */
tc_done(TC_STAT_PASSED);
}
int _tc_semaphore_dynamic()
{
/* 设置TestCase清理回调函数 */
tc_cleanup(_tc_cleanup);
semaphore_dynamic_init();
/* 返回TestCase运行的最长时间 */
return 100;
}
/* 输出函数命令到finsh shell中 */
FINSH_FUNCTION_EXPORT(_tc_semaphore_dynamic, a dynamic semaphore example);
#else
/* 用户应用入口 */
int rt_application_init()
{
semaphore_dynamic_init();
return 0;
}
#endif