xref: /freebsd/lib/libc/gen/getmntinfo.c (revision 193d9e768ba63fcfb187cfd17f461f7d41345048)
1 /*
2  * Copyright (c) 1989, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
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 the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 #if defined(LIBC_SCCS) && !defined(lint)
31 static char sccsid[] = "@(#)getmntinfo.c	8.1 (Berkeley) 6/4/93";
32 #endif /* LIBC_SCCS and not lint */
33 #include <sys/cdefs.h>
34 __FBSDID("$FreeBSD$");
35 
36 #include <sys/param.h>
37 #include <sys/ucred.h>
38 #include <sys/mount.h>
39 #include <stdlib.h>
40 
41 /*
42  * Return information about mounted filesystems.
43  */
44 int
45 getmntinfo(struct statfs **mntbufp, int mode)
46 {
47 	static struct statfs *mntbuf;
48 	static int mntsize;
49 	static long bufsize;
50 
51 	if (mntsize <= 0 && (mntsize = getfsstat(0, 0, MNT_NOWAIT)) < 0)
52 		return (0);
53 	if (bufsize > 0 && (mntsize = getfsstat(mntbuf, bufsize, mode)) < 0)
54 		return (0);
55 	while (bufsize <= mntsize * sizeof(struct statfs)) {
56 		if (mntbuf)
57 			free(mntbuf);
58 		bufsize = (mntsize + 1) * sizeof(struct statfs);
59 		if ((mntbuf = malloc(bufsize)) == NULL)
60 			return (0);
61 		if ((mntsize = getfsstat(mntbuf, bufsize, mode)) < 0)
62 			return (0);
63 	}
64 	*mntbufp = mntbuf;
65 	return (mntsize);
66 }
67