xref: /dragonfly/lib/libc/stdlib/posix_fadvise.c (revision 7d2302ac)
1 /*-
2  * Copyright (c) 2019 The DragonFly Project.  All rights reserved.
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  *
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in
12  *    the documentation and/or other materials provided with the
13  *    distribution.
14  * 3. Neither the name of The DragonFly Project nor the names of its
15  *    contributors may be used to endorse or promote products derived
16  *   from this software without specific, prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
19  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
20  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
21  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
22  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
23  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
24  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
25  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
26  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
27  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
28  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29  * SUCH DAMAGE.
30  */
31 
32 #include "namespace.h"
33 #include <errno.h>
34 #include <fcntl.h>
35 #include <sys/stat.h>
36 #include <machine/limits.h>
37 #include "un-namespace.h"
38 
39 int
40 posix_fadvise(int fd, off_t offset, off_t len, int advice)
41 {
42 	struct stat buf;
43 	int ret;
44 
45 	if (offset < 0 || len < 0 || offset > OFF_MAX - len ||
46 	    advice < POSIX_FADV_NORMAL || advice > POSIX_FADV_NOREUSE)
47 		return (EINVAL);
48 	if ((ret = _fstat(fd, &buf)) != 0)
49 		return (ret);
50 	if (S_ISFIFO(buf.st_mode))
51 		return (ESPIPE);
52 	/* do nothing */
53 	return (0);
54 }
55