[apple/libc.git] / gen / FreeBSD / lockf.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: src/lib/libc/gen/lockf.c,v 1.10 2009/03/04 01:01:26 delphij Exp $");

#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));
}
Commit	Line	Data
1f2f436a	1	/* $NetBSD: lockf.c,v 1.3 2008/04/28 20:22:59 martin Exp $ */
5b2abdfb A	2	/*-
	3	* Copyright (c) 1997 The NetBSD Foundation, Inc.
	4	* All rights reserved.
	5	*
	6	* This code is derived from software contributed to The NetBSD Foundation
	7	* by Klaus Klein.
	8	*
	9	* Redistribution and use in source and binary forms, with or without
	10	* modification, are permitted provided that the following conditions
	11	* are met:
	12	* 1. Redistributions of source code must retain the above copyright
	13	* notice, this list of conditions and the following disclaimer.
	14	* 2. Redistributions in binary form must reproduce the above copyright
	15	* notice, this list of conditions and the following disclaimer in the
	16	* documentation and/or other materials provided with the distribution.
5b2abdfb A	17	*
	18	* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
	19	* ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
	20	* TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
	21	* PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
	22	* BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
	23	* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
	24	* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
	25	* INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
	26	* CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
	27	* ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
	28	* POSSIBILITY OF SUCH DAMAGE.
5b2abdfb A	29	*/
5b2abdfb A	30
9385eb3d	31	#include <sys/cdefs.h>
1f2f436a	32	__FBSDID("$FreeBSD: src/lib/libc/gen/lockf.c,v 1.10 2009/03/04 01:01:26 delphij Exp $");
5b2abdfb	33
9385eb3d	34	#include "namespace.h"
5b2abdfb A	35	#include <errno.h>
	36	#include <fcntl.h>
	37	#include <unistd.h>
9385eb3d	38	#include "un-namespace.h"
5b2abdfb A	39
5b2abdfb A	40	int
1f2f436a	41	lockf(int filedes, int function, off_t size)
5b2abdfb A	42	{
	43	struct flock fl;
	44	int cmd;
	45
	46	fl.l_start = 0;
	47	fl.l_len = size;
	48	fl.l_whence = SEEK_CUR;
	49
	50	switch (function) {
	51	case F_ULOCK:
	52	cmd = F_SETLK;
	53	fl.l_type = F_UNLCK;
	54	break;
	55	case F_LOCK:
	56	cmd = F_SETLKW;
	57	fl.l_type = F_WRLCK;
	58	break;
	59	case F_TLOCK:
	60	cmd = F_SETLK;
	61	fl.l_type = F_WRLCK;
	62	break;
	63	case F_TEST:
	64	fl.l_type = F_WRLCK;
9385eb3d	65	if (_fcntl(filedes, F_GETLK, &fl) == -1)
5b2abdfb	66	return (-1);
1f2f436a	67	if (fl.l_type == F_UNLCK \|\| (fl.l_sysid == 0 && fl.l_pid == getpid()))
5b2abdfb A	68	return (0);
	69	errno = EAGAIN;
	70	return (-1);
	71	/* NOTREACHED */
	72	default:
	73	errno = EINVAL;
	74	return (-1);
	75	/* NOTREACHED */
	76	}
	77
9385eb3d	78	return (_fcntl(filedes, cmd, &fl));
5b2abdfb	79	}