sema.c revision b819cea2f73f98c5662230cc9affc8cc84f77fcf
/*
* This file and its contents are supplied under the terms of the
* Common Development and Distribution License ("CDDL"), version 1.0.
* You may only use this file in accordance with the terms of version
* 1.0 of the CDDL.
*
* A full copy of the text of the CDDL should have accompanied this
* source. A copy of the CDDL is also available via the Internet at
* http://www.illumos.org/license/CDDL.
*/
/*
* Copyright 2013 Nexenta Systems, Inc. All rights reserved.
*/
/*
* semaphore(9f)
*/
/* This is the API we're emulating */
#include <sys/semaphore.h>
#include <sys/errno.h>
#include <sys/debug.h>
/* <synch.h> */
int _lwp_sema_init(lwp_sema_t *, int);
int _lwp_sema_wait(lwp_sema_t *);
int _lwp_sema_trywait(lwp_sema_t *);
int _lwp_sema_post(lwp_sema_t *);
/* ARGSUSED */
void
ksema_init(ksema_t *sem, uint32_t val,
char *name, ksema_type_t st, void *arg)
{
(void) _lwp_sema_init(sem, val);
}
/* ARGSUSED */
void
ksema_destroy(ksema_t *sem)
{
}
void
sema_p(ksema_t *sem)
{
int rv;
do {
rv = _lwp_sema_wait(sem);
} while (rv == EINTR);
}
void
sema_v(ksema_t *sem)
{
(void) _lwp_sema_post(sem);
}
/*
* Return values:
* 1: interrupted
* 0: success
*/
int
sema_p_sig(ksema_t *sem)
{
int rv;
rv = _lwp_sema_wait(sem);
switch (rv) {
case 0:
/* rv = 0 ; success */
break;
case EINTR:
default:
rv = 1; /* interrrupted */
break;
}
return (rv);
}
/*
* Return values:
* 0: could not get semaphore
* 1: successful (backwards from sema_p_sig!)
*/
int
sema_tryp(ksema_t *sem)
{
int rv;
rv = _lwp_sema_trywait(sem);
switch (rv) {
case 0:
rv = 1; /* success */
break;
case EBUSY:
default:
rv = 0; /* failed */
break;
}
return (rv);
}