03831d35f7499c87d51205817c93e9a8d42c4baestevel/*
03831d35f7499c87d51205817c93e9a8d42c4baestevel * CDDL HEADER START
03831d35f7499c87d51205817c93e9a8d42c4baestevel *
03831d35f7499c87d51205817c93e9a8d42c4baestevel * The contents of this file are subject to the terms of the
03831d35f7499c87d51205817c93e9a8d42c4baestevel * Common Development and Distribution License, Version 1.0 only
03831d35f7499c87d51205817c93e9a8d42c4baestevel * (the "License"). You may not use this file except in compliance
03831d35f7499c87d51205817c93e9a8d42c4baestevel * with the License.
03831d35f7499c87d51205817c93e9a8d42c4baestevel *
03831d35f7499c87d51205817c93e9a8d42c4baestevel * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
03831d35f7499c87d51205817c93e9a8d42c4baestevel * or http://www.opensolaris.org/os/licensing.
03831d35f7499c87d51205817c93e9a8d42c4baestevel * See the License for the specific language governing permissions
03831d35f7499c87d51205817c93e9a8d42c4baestevel * and limitations under the License.
03831d35f7499c87d51205817c93e9a8d42c4baestevel *
03831d35f7499c87d51205817c93e9a8d42c4baestevel * When distributing Covered Code, include this CDDL HEADER in each
03831d35f7499c87d51205817c93e9a8d42c4baestevel * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
03831d35f7499c87d51205817c93e9a8d42c4baestevel * If applicable, add the following below this CDDL HEADER, with the
03831d35f7499c87d51205817c93e9a8d42c4baestevel * fields enclosed by brackets "[]" replaced with your own identifying
03831d35f7499c87d51205817c93e9a8d42c4baestevel * information: Portions Copyright [yyyy] [name of copyright owner]
03831d35f7499c87d51205817c93e9a8d42c4baestevel *
03831d35f7499c87d51205817c93e9a8d42c4baestevel * CDDL HEADER END
03831d35f7499c87d51205817c93e9a8d42c4baestevel */
03831d35f7499c87d51205817c93e9a8d42c4baestevel/*
03831d35f7499c87d51205817c93e9a8d42c4baestevel * Copyright 2002 Sun Microsystems, Inc. All rights reserved.
03831d35f7499c87d51205817c93e9a8d42c4baestevel * Use is subject to license terms.
03831d35f7499c87d51205817c93e9a8d42c4baestevel */
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevel#pragma ident "%Z%%M% %I% %E% SMI"
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevel/*
03831d35f7499c87d51205817c93e9a8d42c4baestevel * xsem.c: to provide a semaphore system (used by the smq routines)
03831d35f7499c87d51205817c93e9a8d42c4baestevel *
03831d35f7499c87d51205817c93e9a8d42c4baestevel * these routines come from the libxposix library.
03831d35f7499c87d51205817c93e9a8d42c4baestevel */
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevel#include <pthread.h>
03831d35f7499c87d51205817c93e9a8d42c4baestevel#include <time.h>
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevel#include "xsem.h"
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevelint
03831d35f7499c87d51205817c93e9a8d42c4baestevelxsem_init(xsem_t *sem, int pshared, unsigned int value)
03831d35f7499c87d51205817c93e9a8d42c4baestevel{
03831d35f7499c87d51205817c93e9a8d42c4baestevel if (pshared != 0)
03831d35f7499c87d51205817c93e9a8d42c4baestevel return (-1);
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevel pthread_mutex_init(&sem->semMutex, NULL);
03831d35f7499c87d51205817c93e9a8d42c4baestevel pthread_cond_init(&sem->semCV, NULL);
03831d35f7499c87d51205817c93e9a8d42c4baestevel sem->semaphore = value;
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevel return (0);
03831d35f7499c87d51205817c93e9a8d42c4baestevel}
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevelvoid
03831d35f7499c87d51205817c93e9a8d42c4baestevelxsem_destroy(xsem_t *sem)
03831d35f7499c87d51205817c93e9a8d42c4baestevel{
03831d35f7499c87d51205817c93e9a8d42c4baestevel pthread_mutex_destroy(&sem->semMutex);
03831d35f7499c87d51205817c93e9a8d42c4baestevel pthread_cond_destroy(&sem->semCV);
03831d35f7499c87d51205817c93e9a8d42c4baestevel sem->semaphore = 0;
03831d35f7499c87d51205817c93e9a8d42c4baestevel}
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevelint
03831d35f7499c87d51205817c93e9a8d42c4baestevelxsem_wait(xsem_t *sem)
03831d35f7499c87d51205817c93e9a8d42c4baestevel{
03831d35f7499c87d51205817c93e9a8d42c4baestevel pthread_mutex_lock(&sem->semMutex);
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevel if (sem->semaphore < 0) {
03831d35f7499c87d51205817c93e9a8d42c4baestevel sem->semaphore = 0;
03831d35f7499c87d51205817c93e9a8d42c4baestevel pthread_mutex_unlock(&sem->semMutex);
03831d35f7499c87d51205817c93e9a8d42c4baestevel return (XSEM_ERROR);
03831d35f7499c87d51205817c93e9a8d42c4baestevel }
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevel if (sem->semaphore > 0) {
03831d35f7499c87d51205817c93e9a8d42c4baestevel sem->semaphore--;
03831d35f7499c87d51205817c93e9a8d42c4baestevel } else {
03831d35f7499c87d51205817c93e9a8d42c4baestevel while (sem->semaphore == 0)
03831d35f7499c87d51205817c93e9a8d42c4baestevel pthread_cond_wait(&sem->semCV, &sem->semMutex);
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevel if (sem->semaphore != 0) {
03831d35f7499c87d51205817c93e9a8d42c4baestevel sem->semaphore--;
03831d35f7499c87d51205817c93e9a8d42c4baestevel } else {
03831d35f7499c87d51205817c93e9a8d42c4baestevel pthread_mutex_unlock(&sem->semMutex);
03831d35f7499c87d51205817c93e9a8d42c4baestevel return (XSEM_ERROR);
03831d35f7499c87d51205817c93e9a8d42c4baestevel }
03831d35f7499c87d51205817c93e9a8d42c4baestevel }
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevel pthread_mutex_unlock(&sem->semMutex);
03831d35f7499c87d51205817c93e9a8d42c4baestevel return (0);
03831d35f7499c87d51205817c93e9a8d42c4baestevel}
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevelint
03831d35f7499c87d51205817c93e9a8d42c4baestevelxsem_trywait(xsem_t *sem)
03831d35f7499c87d51205817c93e9a8d42c4baestevel{
03831d35f7499c87d51205817c93e9a8d42c4baestevel pthread_mutex_lock(&sem->semMutex);
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevel if (sem->semaphore < 0) {
03831d35f7499c87d51205817c93e9a8d42c4baestevel sem->semaphore = 0;
03831d35f7499c87d51205817c93e9a8d42c4baestevel pthread_mutex_unlock(&sem->semMutex);
03831d35f7499c87d51205817c93e9a8d42c4baestevel return (XSEM_ERROR);
03831d35f7499c87d51205817c93e9a8d42c4baestevel }
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevel if (sem->semaphore == 0) {
03831d35f7499c87d51205817c93e9a8d42c4baestevel pthread_mutex_unlock(&sem->semMutex);
03831d35f7499c87d51205817c93e9a8d42c4baestevel return (XSEM_EBUSY);
03831d35f7499c87d51205817c93e9a8d42c4baestevel } else {
03831d35f7499c87d51205817c93e9a8d42c4baestevel sem->semaphore--;
03831d35f7499c87d51205817c93e9a8d42c4baestevel }
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevel pthread_mutex_unlock(&sem->semMutex);
03831d35f7499c87d51205817c93e9a8d42c4baestevel return (0);
03831d35f7499c87d51205817c93e9a8d42c4baestevel}
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevelint
03831d35f7499c87d51205817c93e9a8d42c4baestevelxsem_post(xsem_t *sem)
03831d35f7499c87d51205817c93e9a8d42c4baestevel{
03831d35f7499c87d51205817c93e9a8d42c4baestevel pthread_mutex_lock(&sem->semMutex);
03831d35f7499c87d51205817c93e9a8d42c4baestevel sem->semaphore++;
03831d35f7499c87d51205817c93e9a8d42c4baestevel pthread_cond_signal(&sem->semCV);
03831d35f7499c87d51205817c93e9a8d42c4baestevel pthread_mutex_unlock(&sem->semMutex);
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevel return (0);
03831d35f7499c87d51205817c93e9a8d42c4baestevel}
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevelvoid
03831d35f7499c87d51205817c93e9a8d42c4baestevelxsem_getvalue(xsem_t *sem, int *sval)
03831d35f7499c87d51205817c93e9a8d42c4baestevel{
03831d35f7499c87d51205817c93e9a8d42c4baestevel *sval = sem->semaphore;
03831d35f7499c87d51205817c93e9a8d42c4baestevel}
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevelint
03831d35f7499c87d51205817c93e9a8d42c4baestevelxsem_xwait(xsem_t *sem, int timeout, timestruc_t *mytime)
03831d35f7499c87d51205817c93e9a8d42c4baestevel{
03831d35f7499c87d51205817c93e9a8d42c4baestevel int status;
03831d35f7499c87d51205817c93e9a8d42c4baestevel timestruc_t delay;
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevel if (timeout == 0)
03831d35f7499c87d51205817c93e9a8d42c4baestevel return (xsem_wait(sem));
03831d35f7499c87d51205817c93e9a8d42c4baestevel else {
03831d35f7499c87d51205817c93e9a8d42c4baestevel pthread_mutex_lock(&sem->semMutex);
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevel if (sem->semaphore < 0) {
03831d35f7499c87d51205817c93e9a8d42c4baestevel sem->semaphore = 0;
03831d35f7499c87d51205817c93e9a8d42c4baestevel pthread_mutex_unlock(&sem->semMutex);
03831d35f7499c87d51205817c93e9a8d42c4baestevel return (XSEM_ERROR);
03831d35f7499c87d51205817c93e9a8d42c4baestevel }
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevel if (sem->semaphore > 0) {
03831d35f7499c87d51205817c93e9a8d42c4baestevel sem->semaphore--;
03831d35f7499c87d51205817c93e9a8d42c4baestevel } else {
03831d35f7499c87d51205817c93e9a8d42c4baestevel status = 0;
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevel delay = *mytime;
03831d35f7499c87d51205817c93e9a8d42c4baestevel delay.tv_sec = delay.tv_sec + time(NULL);
03831d35f7499c87d51205817c93e9a8d42c4baestevel while ((sem->semaphore == 0) && (status == 0)) {
03831d35f7499c87d51205817c93e9a8d42c4baestevel status = pthread_cond_timedwait(&sem->semCV,
03831d35f7499c87d51205817c93e9a8d42c4baestevel &sem->semMutex, &delay);
03831d35f7499c87d51205817c93e9a8d42c4baestevel }
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevel /*
03831d35f7499c87d51205817c93e9a8d42c4baestevel * Check one more time in case thread didn't have a
03831d35f7499c87d51205817c93e9a8d42c4baestevel * chance to check before timeout ??? TBD
03831d35f7499c87d51205817c93e9a8d42c4baestevel */
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevel if (status != 0) {
03831d35f7499c87d51205817c93e9a8d42c4baestevel pthread_mutex_unlock(&sem->semMutex);
03831d35f7499c87d51205817c93e9a8d42c4baestevel return (XSEM_ETIME);
03831d35f7499c87d51205817c93e9a8d42c4baestevel } else if (sem->semaphore != 0) {
03831d35f7499c87d51205817c93e9a8d42c4baestevel sem->semaphore--;
03831d35f7499c87d51205817c93e9a8d42c4baestevel } else {
03831d35f7499c87d51205817c93e9a8d42c4baestevel pthread_mutex_unlock(&sem->semMutex);
03831d35f7499c87d51205817c93e9a8d42c4baestevel return (XSEM_ERROR);
03831d35f7499c87d51205817c93e9a8d42c4baestevel }
03831d35f7499c87d51205817c93e9a8d42c4baestevel }
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevel pthread_mutex_unlock(&sem->semMutex);
03831d35f7499c87d51205817c93e9a8d42c4baestevel }
03831d35f7499c87d51205817c93e9a8d42c4baestevel
03831d35f7499c87d51205817c93e9a8d42c4baestevel return (0);
03831d35f7499c87d51205817c93e9a8d42c4baestevel}