1 /*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License, Version 1.0 only
6 * (the "License"). You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or https://opensource.org/licenses/CDDL-1.0.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22 /*
23 * Copyright 2005 Sun Microsystems, Inc. All rights reserved.
24 * Copyright 2006 Ricardo Correia. All rights reserved.
25 * Use is subject to license terms.
26 */
27
28 /* Copyright (c) 1988 AT&T */
29 /* All Rights Reserved */
30
31 #include <stdio.h>
32 #include <string.h>
33 #include <mntent.h>
34 #include <sys/errno.h>
35 #include <sys/mnttab.h>
36
37 #include <sys/types.h>
38 #include <sys/sysmacros.h>
39 #include <sys/stat.h>
40 #include <unistd.h>
41 #include <libzutil.h>
42
43 #define BUFSIZE (MNT_LINE_MAX + 2)
44
45 static __thread char buf[BUFSIZE];
46
47 #define DIFF(xx) ( \
48 (mrefp->xx != NULL) && \
49 (mgetp->xx == NULL || strcmp(mrefp->xx, mgetp->xx) != 0))
50
51 int
getmntany(FILE * fp,struct mnttab * mgetp,struct mnttab * mrefp)52 getmntany(FILE *fp, struct mnttab *mgetp, struct mnttab *mrefp)
53 {
54 int ret;
55
56 while (
57 ((ret = _sol_getmntent(fp, mgetp)) == 0) && (
58 DIFF(mnt_special) || DIFF(mnt_mountp) ||
59 DIFF(mnt_fstype) || DIFF(mnt_mntopts))) { }
60
61 return (ret);
62 }
63
64 int
_sol_getmntent(FILE * fp,struct mnttab * mgetp)65 _sol_getmntent(FILE *fp, struct mnttab *mgetp)
66 {
67 struct mntent mntbuf;
68 struct mntent *ret;
69
70 ret = getmntent_r(fp, &mntbuf, buf, BUFSIZE);
71
72 if (ret != NULL) {
73 mgetp->mnt_special = mntbuf.mnt_fsname;
74 mgetp->mnt_mountp = mntbuf.mnt_dir;
75 mgetp->mnt_fstype = mntbuf.mnt_type;
76 mgetp->mnt_mntopts = mntbuf.mnt_opts;
77 return (0);
78 }
79
80 if (feof(fp))
81 return (-1);
82
83 return (MNT_TOOLONG);
84 }
85
86 static int
getextmntent_impl(FILE * fp,struct extmnttab * mp)87 getextmntent_impl(FILE *fp, struct extmnttab *mp)
88 {
89 int ret;
90 struct stat64 st;
91
92 ret = _sol_getmntent(fp, (struct mnttab *)mp);
93 if (ret == 0) {
94 if (stat64(mp->mnt_mountp, &st) != 0) {
95 mp->mnt_major = 0;
96 mp->mnt_minor = 0;
97 return (ret);
98 }
99 mp->mnt_major = major(st.st_dev);
100 mp->mnt_minor = minor(st.st_dev);
101 }
102
103 return (ret);
104 }
105
106 int
getextmntent(const char * path,struct extmnttab * entry,struct stat64 * statbuf)107 getextmntent(const char *path, struct extmnttab *entry, struct stat64 *statbuf)
108 {
109 struct stat64 st;
110 FILE *fp;
111 int match;
112
113 if (strlen(path) >= MAXPATHLEN) {
114 (void) fprintf(stderr, "invalid object; pathname too long\n");
115 return (-1);
116 }
117
118 /*
119 * Search for the path in /proc/self/mounts. Rather than looking for the
120 * specific path, which can be fooled by non-standard paths (i.e. ".."
121 * or "//"), we stat() the path and search for the corresponding
122 * (major,minor) device pair.
123 */
124 if (stat64(path, statbuf) != 0) {
125 (void) fprintf(stderr, "cannot open '%s': %s\n",
126 path, zfs_strerror(errno));
127 return (-1);
128 }
129
130
131 if ((fp = fopen(MNTTAB, "re")) == NULL) {
132 (void) fprintf(stderr, "cannot open %s\n", MNTTAB);
133 return (-1);
134 }
135
136 /*
137 * Search for the given (major,minor) pair in the mount table.
138 */
139
140 match = 0;
141 while (getextmntent_impl(fp, entry) == 0) {
142 if (makedev(entry->mnt_major, entry->mnt_minor) ==
143 statbuf->st_dev) {
144 match = 1;
145 break;
146 }
147 }
148 (void) fclose(fp);
149
150 if (!match) {
151 (void) fprintf(stderr, "cannot find mountpoint for '%s'\n",
152 path);
153 return (-1);
154 }
155
156 if (stat64(entry->mnt_mountp, &st) != 0) {
157 entry->mnt_major = 0;
158 entry->mnt_minor = 0;
159 return (-1);
160 }
161
162 return (0);
163 }
164