xref: /dragonfly/lib/libc/gen/getmntvinfo.c (revision cae2835b)
1 /*
2  * Copyright (c) 1989, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  * Copyright (c) 2008 The DragonFly Project.  All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. Neither the name of the University nor the names of its contributors
15  *    may be used to endorse or promote products derived from this software
16  *    without specific prior written permission.
17  *
18  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
19  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
22  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28  * SUCH DAMAGE.
29  *
30  * @(#)getmntinfo.c	8.1 (Berkeley) 6/4/93
31  */
32 
33 #include <sys/param.h>
34 #include <sys/ucred.h>
35 #include <sys/mount.h>
36 #include <sys/statvfs.h>
37 #include <stdlib.h>
38 
39 /*
40  * Return information about mounted filesystems.
41  */
42 int
43 getmntvinfo(struct statfs **mntbufp, struct statvfs **mntvbufp, int flags)
44 {
45 	static struct statfs *mntsbuf;
46 	static struct statvfs *mntvbuf;
47 	static int mntsize;
48 	static int bufsize;
49 	static int vbufsize;
50 
51 	if (mntsize <= 0 && (mntsize = getvfsstat(NULL, NULL, 0, MNT_NOWAIT)) < 0)
52 		return (0);
53 	if (vbufsize > 0 && (mntsize = getvfsstat(mntsbuf, mntvbuf, vbufsize, flags)) < 0)
54 		return (0);
55 	while (vbufsize <= mntsize * (int)sizeof(struct statvfs)) {
56 		if (mntsbuf)
57 			free(mntsbuf);
58 		bufsize = (mntsize + 1) * sizeof(struct statfs);
59 		vbufsize = (mntsize + 1) * sizeof(struct statvfs);
60 		if ((mntsbuf = (struct statfs *)malloc(bufsize)) == NULL)
61 			return (0);
62 		if ((mntvbuf = (struct statvfs *)malloc(vbufsize)) == NULL)
63 			return (0);
64 		if ((mntsize = getvfsstat(mntsbuf, mntvbuf, vbufsize, flags)) < 0)
65 			return (0);
66 	}
67 	*mntbufp = mntsbuf;
68 	*mntvbufp = mntvbuf;
69 	return (mntsize);
70 }
71 
72