38 lines
760 B
C
38 lines
760 B
C
|
/*
|
||
|
|
* Copyright (c) 2006-2023, RT-Thread Development Team
|
||
|
|
*
|
||
|
|
* SPDX-License-Identifier: Apache-2.0
|
||
|
|
*
|
||
|
|
* Change Logs:
|
||
|
|
* Date Author Notes
|
||
|
|
* 2023-03-24 WangXiaoyao Complete testcase for synchronization
|
||
|
|
*/
|
||
|
|
#ifndef __SEMAPHORE_H__
|
||
|
|
#define __SEMAPHORE_H__
|
||
|
|
|
||
|
|
#include <stdatomic.h>
|
||
|
|
|
||
|
|
typedef struct {
|
||
|
|
atomic_int count;
|
||
|
|
} semaphore_t;
|
||
|
|
|
||
|
|
void semaphore_init(semaphore_t *sem, int count)
|
||
|
|
{
|
||
|
|
atomic_init(&sem->count, count);
|
||
|
|
}
|
||
|
|
|
||
|
|
void semaphore_wait(semaphore_t *sem)
|
||
|
|
{
|
||
|
|
int count;
|
||
|
|
do {
|
||
|
|
count = atomic_load(&sem->count);
|
||
|
|
} while (count == 0 || !atomic_compare_exchange_weak(&sem->count, &count, count - 1));
|
||
|
|
}
|
||
|
|
|
||
|
|
void semaphore_signal(semaphore_t *sem)
|
||
|
|
{
|
||
|
|
atomic_fetch_add(&sem->count, 1);
|
||
|
|
}
|
||
|
|
|
||
|
|
#endif /* __SEMAPHORE_H__ */
|