xref: /dragonfly/lib/libc/gen/getmntinfo.c (revision 0d27ae55)
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  * @(#)getmntinfo.c	8.1 (Berkeley) 6/4/93
30  */
31 
32 #include <sys/param.h>
33 #include <sys/ucred.h>
34 #include <sys/mount.h>
35 #include <stdlib.h>
36 
37 /*
38  * Return information about mounted filesystems.
39  */
40 int
41 getmntinfo(struct statfs **mntbufp, int flags)
42 {
43 	static struct statfs *mntbuf;
44 	static int mntsize;
45 	static int bufsize;
46 
47 	if (mntsize <= 0 && (mntsize = getfsstat(0, 0, MNT_NOWAIT)) < 0)
48 		return (0);
49 	if (bufsize > 0 && (mntsize = getfsstat(mntbuf, bufsize, flags)) < 0)
50 		return (0);
51 	while (bufsize <= mntsize * (int)sizeof(struct statfs)) {
52 		if (mntbuf)
53 			free(mntbuf);
54 		bufsize = (mntsize + 1) * sizeof(struct statfs);
55 		if ((mntbuf = (struct statfs *)malloc(bufsize)) == NULL)
56 			return (0);
57 		if ((mntsize = getfsstat(mntbuf, bufsize, flags)) < 0)
58 			return (0);
59 	}
60 	*mntbufp = mntbuf;
61 	return (mntsize);
62 }
63