80 lines
2.3 KiB
C
80 lines
2.3 KiB
C
/* $NetBSD: lockf.c,v 1.3 2008/04/28 20:22:59 martin Exp $ */
|
|
/*-
|
|
* Copyright (c) 1997 The NetBSD Foundation, Inc.
|
|
* All rights reserved.
|
|
*
|
|
* This code is derived from software contributed to The NetBSD Foundation
|
|
* by Klaus Klein.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
|
|
* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
|
|
* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
|
|
* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
|
|
* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
|
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
|
|
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
|
|
* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
|
|
* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
|
|
* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|
* POSSIBILITY OF SUCH DAMAGE.
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__FBSDID("$FreeBSD$");
|
|
|
|
#include "namespace.h"
|
|
#include <errno.h>
|
|
#include <fcntl.h>
|
|
#include <unistd.h>
|
|
#include "un-namespace.h"
|
|
|
|
int
|
|
lockf(int filedes, int function, off_t size)
|
|
{
|
|
struct flock fl;
|
|
int cmd;
|
|
|
|
fl.l_start = 0;
|
|
fl.l_len = size;
|
|
fl.l_whence = SEEK_CUR;
|
|
|
|
switch (function) {
|
|
case F_ULOCK:
|
|
cmd = F_SETLK;
|
|
fl.l_type = F_UNLCK;
|
|
break;
|
|
case F_LOCK:
|
|
cmd = F_SETLKW;
|
|
fl.l_type = F_WRLCK;
|
|
break;
|
|
case F_TLOCK:
|
|
cmd = F_SETLK;
|
|
fl.l_type = F_WRLCK;
|
|
break;
|
|
case F_TEST:
|
|
fl.l_type = F_WRLCK;
|
|
if (_fcntl(filedes, F_GETLK, &fl) == -1)
|
|
return (-1);
|
|
if (fl.l_type == F_UNLCK || (fl.l_sysid == 0 && fl.l_pid == getpid()))
|
|
return (0);
|
|
errno = EAGAIN;
|
|
return (-1);
|
|
/* NOTREACHED */
|
|
default:
|
|
errno = EINVAL;
|
|
return (-1);
|
|
/* NOTREACHED */
|
|
}
|
|
|
|
return (_fcntl(filedes, cmd, &fl));
|
|
}
|