xref: /freebsd/sys/contrib/openzfs/lib/libspl/mkdirp.c (revision 5f4c09dd85bff675e0ca63c55ea3c517e0fddfcc)
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 https://opensource.org/licenses/CDDL-1.0.
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 2008 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*	Copyright (c) 1988 AT&T	*/
28 /*	  All Rights Reserved  	*/
29 
30 /*
31  * Creates directory and it's parents if the parents do not
32  * exist yet.
33  *
34  * Returns -1 if fails for reasons other than non-existing
35  * parents.
36  * Does NOT simplify pathnames with . or .. in them.
37  */
38 
39 #include <sys/types.h>
40 #include <libgen.h>
41 #include <stdlib.h>
42 #include <unistd.h>
43 #include <errno.h>
44 #include <string.h>
45 #include <sys/stat.h>
46 
47 static char *simplify(const char *str);
48 
49 int
50 mkdirp(const char *d, mode_t mode)
51 {
52 	char  *endptr, *ptr, *slash, *str;
53 
54 	str = simplify(d);
55 
56 	/* If space couldn't be allocated for the simplified names, return. */
57 
58 	if (str == NULL)
59 		return (-1);
60 
61 		/* Try to make the directory */
62 
63 	if (mkdir(str, mode) == 0) {
64 		free(str);
65 		return (0);
66 	}
67 	if (errno != ENOENT) {
68 		free(str);
69 		return (-1);
70 	}
71 	endptr = strrchr(str, '\0');
72 	slash = strrchr(str, '/');
73 
74 		/* Search upward for the non-existing parent */
75 
76 	while (slash != NULL) {
77 
78 		ptr = slash;
79 		*ptr = '\0';
80 
81 			/* If reached an existing parent, break */
82 
83 		if (access(str, F_OK) == 0)
84 			break;
85 
86 			/* If non-existing parent */
87 
88 		else {
89 			slash = strrchr(str, '/');
90 
91 				/* If under / or current directory, make it. */
92 
93 			if (slash == NULL || slash == str) {
94 				if (mkdir(str, mode) != 0 && errno != EEXIST) {
95 					free(str);
96 					return (-1);
97 				}
98 				break;
99 			}
100 		}
101 	}
102 
103 	/* Create directories starting from upmost non-existing parent */
104 
105 	while ((ptr = strchr(str, '\0')) != endptr) {
106 		*ptr = '/';
107 		if (mkdir(str, mode) != 0 && errno != EEXIST) {
108 			/*
109 			 *  If the mkdir fails because str already
110 			 *  exists (EEXIST), then str has the form
111 			 *  "existing-dir/..", and this is really
112 			 *  ok. (Remember, this loop is creating the
113 			 *  portion of the path that didn't exist)
114 			 */
115 			free(str);
116 			return (-1);
117 		}
118 	}
119 	free(str);
120 	return (0);
121 }
122 
123 /*
124  *	simplify - given a pathname, simplify that path by removing
125  *		   duplicate contiguous slashes.
126  *
127  *		   A simplified copy of the argument is returned to the
128  *		   caller, or NULL is returned on error.
129  *
130  *		   The caller should handle error reporting based upon the
131  *		   returned value, and should free the returned value,
132  *		   when appropriate.
133  */
134 
135 static char *
136 simplify(const char *str)
137 {
138 	int i;
139 	size_t mbPathlen;	/* length of multi-byte path */
140 	size_t wcPathlen;	/* length of wide-character path */
141 	wchar_t *wptr;		/* scratch pointer */
142 	wchar_t *wcPath;	/* wide-character version of the path */
143 	char *mbPath;		/* The copy fo the path to be returned */
144 
145 	/*
146 	 *  bail out if there is nothing there.
147 	 */
148 
149 	if (!str) {
150 		errno = ENOENT;
151 		return (NULL);
152 	}
153 
154 	/*
155 	 *  Get a copy of the argument.
156 	 */
157 
158 	if ((mbPath = strdup(str)) == NULL) {
159 		return (NULL);
160 	}
161 
162 	/*
163 	 *  convert the multi-byte version of the path to a
164 	 *  wide-character rendering, for doing our figuring.
165 	 */
166 
167 	mbPathlen = strlen(mbPath);
168 
169 	if ((wcPath = calloc(mbPathlen+1, sizeof (wchar_t))) == NULL) {
170 		free(mbPath);
171 		return (NULL);
172 	}
173 
174 	if ((wcPathlen = mbstowcs(wcPath, mbPath, mbPathlen)) == (size_t)-1) {
175 		free(mbPath);
176 		free(wcPath);
177 		return (NULL);
178 	}
179 
180 	/*
181 	 *  remove duplicate slashes first ("//../" -> "/")
182 	 */
183 
184 	for (wptr = wcPath, i = 0; i < wcPathlen; i++) {
185 		*wptr++ = wcPath[i];
186 
187 		if (wcPath[i] == '/') {
188 			i++;
189 
190 			while (wcPath[i] == '/') {
191 				i++;
192 			}
193 
194 			i--;
195 		}
196 	}
197 
198 	*wptr = '\0';
199 
200 	/*
201 	 *  now convert back to the multi-byte format.
202 	 */
203 
204 	if (wcstombs(mbPath, wcPath, mbPathlen) == (size_t)-1) {
205 		free(mbPath);
206 		free(wcPath);
207 		return (NULL);
208 	}
209 
210 	free(wcPath);
211 	return (mbPath);
212 }
213