lib/libspl/mkdirp.c

   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 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 vlaue, 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                 return (NULL);
 151
 152         /*
 153          *  Get a copy of the argument.
 154          */
 155
 156         if ((mbPath = strdup(str)) == NULL) {
 157                 return (NULL);
 158         }
 159
 160         /*
 161          *  convert the multi-byte version of the path to a
 162          *  wide-character rendering, for doing our figuring.
 163          */
 164
 165         mbPathlen = strlen(mbPath);
 166
 167         if ((wcPath = calloc(sizeof (wchar_t), mbPathlen+1)) == NULL) {
 168                 free(mbPath);
 169                 return (NULL);
 170         }
 171
 172         if ((wcPathlen = mbstowcs(wcPath, mbPath, mbPathlen)) == (size_t)-1) {
 173                 free(mbPath);
 174                 free(wcPath);
 175                 return (NULL);
 176         }
 177
 178         /*
 179          *  remove duplicate slashes first ("//../" -> "/")
 180          */
 181
 182         for (wptr = wcPath, i = 0; i < wcPathlen; i++) {
 183                 *wptr++ = wcPath[i];
 184
 185                 if (wcPath[i] == '/') {
 186                         i++;
 187
 188                         while (wcPath[i] == '/') {
 189                                 i++;
 190                         }
 191
 192                         i--;
 193                 }
 194         }
 195
 196         *wptr = '\0';
 197
 198         /*
 199          *  now convert back to the multi-byte format.
 200          */
 201
 202         if (wcstombs(mbPath, wcPath, mbPathlen) == (size_t)-1) {
 203                 free(mbPath);
 204                 free(wcPath);
 205                 return (NULL);
 206         }
 207
 208         free(wcPath);
 209         return (mbPath);
 210 }