semaphore.h

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/*
 * Copyright (C) 2017 TriaGnoSys GmbH
 *               2013 Freie Universität Berlin
 *
 * This file is subject to the terms and conditions of the GNU Lesser
 * General Public License v2.1. See the file LICENSE in the top level
 * directory for more details.
 */
 
#ifndef SEMAPHORE_H
#define SEMAPHORE_H
 
#include <errno.h>
#include <time.h>
 
#include "sema.h"
 
#ifdef __cplusplus
extern "C" {
#endif
 
typedef sema_t sem_t;
 
#define SEM_FAILED      ((sem_t *) 0)
 
static inline int sem_init(sem_t *sem, int pshared, unsigned value)
{
    sema_create((sema_t *)sem, value);
    (void)pshared;
    return 0;
}
 
static inline int sem_destroy(sem_t *sem)
{
    sema_destroy((sema_t *)sem);
    return 0;
}
 
static inline int sem_post(sem_t *sem)
{
    int res = sema_post((sema_t *)sem);
 
    if (res < 0) {
        errno = -res;
        return -1;
    }
    return 0;
}
 
static inline int sem_wait(sem_t *sem)
{
    int res = sema_wait((sema_t *)sem);
 
    if (res < 0) {
        errno = -res;
        return -1;
    }
    return 0;
}
 
static inline sem_t *sem_open(const char *name, int oflag, ...)
{
    (void)name;
    (void)oflag;
    errno = ENOMEM;
    return SEM_FAILED;
}
 
static inline int sem_close(sem_t *sem)
{
    (void)sem;
    errno = EINVAL;
    return -1;
}
 
static inline int sem_unlink(const char *name)
{
    (void)name;
    errno = ENOENT;
    return -1;
}
 
int sem_timedwait(sem_t *sem, const struct timespec *abstime);
 
static inline int sem_trywait(sem_t *sem)
{
    int res = sema_try_wait((sema_t *)sem);
 
    if (res < 0) {
        errno = -res;
        return -1;
    }
    return 0;
}
 
static inline int sem_getvalue(sem_t *sem, int *sval)
{
    if (sem != NULL) {
        *sval = (int)sem->value;
        return 0;
    }
    errno = EINVAL;
    return -1;
}
 
#ifdef __cplusplus
}
#endif
 
#endif /* SEMAPHORE_H */