xref: /freebsd/sys/contrib/openzfs/lib/libzutil/zutil_device_path.c (revision 4ab5c88da28780334f48eae56db52d8e77c871cf)
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 (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright (c) 2005, 2010, Oracle and/or its affiliates. All rights reserved.
24  */
25 
26 #include <errno.h>
27 #include <stdio.h>
28 #include <stdlib.h>
29 #include <string.h>
30 #include <unistd.h>
31 
32 #include <libzutil.h>
33 
34 /*
35  * Given a shorthand device name check if a file by that name exists in any
36  * of the 'zpool_default_import_path' or ZPOOL_IMPORT_PATH directories.  If
37  * one is found, store its fully qualified path in the 'path' buffer passed
38  * by the caller and return 0, otherwise return an error.
39  */
40 int
41 zfs_resolve_shortname(const char *name, char *path, size_t len)
42 {
43 	int i, error = -1;
44 	char *dir, *env, *envdup, *tmp = NULL;
45 
46 	env = getenv("ZPOOL_IMPORT_PATH");
47 	errno = ENOENT;
48 
49 	if (env) {
50 		envdup = strdup(env);
51 		for (dir = strtok_r(envdup, ":", &tmp);
52 		    dir != NULL && error != 0;
53 		    dir = strtok_r(NULL, ":", &tmp)) {
54 			(void) snprintf(path, len, "%s/%s", dir, name);
55 			error = access(path, F_OK);
56 		}
57 		free(envdup);
58 	} else {
59 		const char * const *zpool_default_import_path;
60 		size_t count;
61 
62 		zpool_default_import_path = zpool_default_search_paths(&count);
63 
64 		for (i = 0; i < count && error < 0; i++) {
65 			(void) snprintf(path, len, "%s/%s",
66 			    zpool_default_import_path[i], name);
67 			error = access(path, F_OK);
68 		}
69 	}
70 
71 	return (error ? ENOENT : 0);
72 }
73 
74 /*
75  * Given a shorthand device name look for a match against 'cmp_name'.  This
76  * is done by checking all prefix expansions using either the default
77  * 'zpool_default_import_paths' or the ZPOOL_IMPORT_PATH environment
78  * variable.  Proper partition suffixes will be appended if this is a
79  * whole disk.  When a match is found 0 is returned otherwise ENOENT.
80  */
81 static int
82 zfs_strcmp_shortname(const char *name, const char *cmp_name, int wholedisk)
83 {
84 	int path_len, cmp_len, i = 0, error = ENOENT;
85 	char *dir, *env, *envdup = NULL, *tmp = NULL;
86 	char path_name[MAXPATHLEN];
87 	const char * const *zpool_default_import_path = NULL;
88 	size_t count;
89 
90 	cmp_len = strlen(cmp_name);
91 	env = getenv("ZPOOL_IMPORT_PATH");
92 
93 	if (env) {
94 		envdup = strdup(env);
95 		dir = strtok_r(envdup, ":", &tmp);
96 	} else {
97 		zpool_default_import_path = zpool_default_search_paths(&count);
98 		dir = (char *)zpool_default_import_path[i];
99 	}
100 
101 	while (dir) {
102 		/* Trim trailing directory slashes from ZPOOL_IMPORT_PATH */
103 		if (env) {
104 			while (dir[strlen(dir)-1] == '/')
105 				dir[strlen(dir)-1] = '\0';
106 		}
107 
108 		path_len = snprintf(path_name, MAXPATHLEN, "%s/%s", dir, name);
109 		if (wholedisk)
110 			path_len = zfs_append_partition(path_name, MAXPATHLEN);
111 
112 		if ((path_len == cmp_len) && strcmp(path_name, cmp_name) == 0) {
113 			error = 0;
114 			break;
115 		}
116 
117 		if (env) {
118 			dir = strtok_r(NULL, ":", &tmp);
119 		} else if (++i < count) {
120 			dir = (char *)zpool_default_import_path[i];
121 		} else {
122 			dir = NULL;
123 		}
124 	}
125 
126 	if (env)
127 		free(envdup);
128 
129 	return (error);
130 }
131 
132 /*
133  * Given either a shorthand or fully qualified path name look for a match
134  * against 'cmp'.  The passed name will be expanded as needed for comparison
135  * purposes and redundant slashes stripped to ensure an accurate match.
136  */
137 int
138 zfs_strcmp_pathname(const char *name, const char *cmp, int wholedisk)
139 {
140 	int path_len, cmp_len;
141 	char path_name[MAXPATHLEN];
142 	char cmp_name[MAXPATHLEN];
143 	char *dir, *tmp = NULL;
144 
145 	/* Strip redundant slashes if they exist due to ZPOOL_IMPORT_PATH */
146 	cmp_name[0] = '\0';
147 	(void) strlcpy(path_name, cmp, sizeof (path_name));
148 	for (dir = strtok_r(path_name, "/", &tmp);
149 	    dir != NULL;
150 	    dir = strtok_r(NULL, "/", &tmp)) {
151 		strlcat(cmp_name, "/", sizeof (cmp_name));
152 		strlcat(cmp_name, dir, sizeof (cmp_name));
153 	}
154 
155 	if (name[0] != '/')
156 		return (zfs_strcmp_shortname(name, cmp_name, wholedisk));
157 
158 	(void) strlcpy(path_name, name, MAXPATHLEN);
159 	path_len = strlen(path_name);
160 	cmp_len = strlen(cmp_name);
161 
162 	if (wholedisk) {
163 		path_len = zfs_append_partition(path_name, MAXPATHLEN);
164 		if (path_len == -1)
165 			return (ENOMEM);
166 	}
167 
168 	if ((path_len != cmp_len) || strcmp(path_name, cmp_name))
169 		return (ENOENT);
170 
171 	return (0);
172 }
173