lockf.c revision a574db851cdc636fc3939b68e80d79fe7fbd57f2
/*
* CDDL HEADER START
*
* The contents of this file are subject to the terms of the
* Common Development and Distribution License (the "License").
* You may not use this file except in compliance with the License.
*
* You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
* or http://www.opensolaris.org/os/licensing.
* See the License for the specific language governing permissions
* and limitations under the License.
*
* When distributing Covered Code, include this CDDL HEADER in each
* file and include the License file at usr/src/OPENSOLARIS.LICENSE.
* If applicable, add the following below this CDDL HEADER, with the
* fields enclosed by brackets "[]" replaced with your own identifying
* information: Portions Copyright [yyyy] [name of copyright owner]
*
* CDDL HEADER END
*/
/*
* Copyright 2008 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms.
*/
#pragma ident "%Z%%M% %I% %E% SMI"
/* Copyright (c) 1988 AT&T */
/* All Rights Reserved */
#include <sys/feature_tests.h>
#if !defined(_LP64) && _FILE_OFFSET_BITS == 64
#define __lockf __lockf64
#endif
#include "synonyms.h"
#include <sys/types.h>
#include <unistd.h>
#include <errno.h>
#include <fcntl.h>
int
__lockf(int fildes, int function, off_t size)
{
struct flock l;
int rv;
l.l_whence = 1;
if (size < 0) {
l.l_start = size;
l.l_len = -size;
} else {
l.l_start = (off_t)0;
l.l_len = size;
}
switch (function) {
case F_ULOCK:
l.l_type = F_UNLCK;
rv = fcntl(fildes, F_SETLK, &l);
break;
case F_LOCK:
l.l_type = F_WRLCK;
rv = fcntl(fildes, F_SETLKW, &l);
break;
case F_TLOCK:
l.l_type = F_WRLCK;
rv = fcntl(fildes, F_SETLK, &l);
break;
case F_TEST:
l.l_type = F_WRLCK;
rv = fcntl(fildes, F_GETLK, &l);
if (rv != -1) {
if (l.l_type == F_UNLCK)
return (0);
else {
errno = EAGAIN;
return (-1);
}
}
break;
default:
errno = EINVAL;
return (-1);
}
if (rv < 0) {
switch (errno) {
case EMFILE:
case ENOSPC:
case ENOLCK:
/*
* A deadlock error is given if we run out of resources,
* in compliance with /usr/group standards.
*/
errno = EDEADLK;
break;
default:
break;
}
}
return (rv);
}