1 /* mkdir-p.c -- Ensure that a directory and its parents exist.
3 Copyright (C) 1990, 1997-2000, 2002-2007, 2009-2010 Free Software
6 This program is free software: you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 3 of the License, or
9 (at your option) any later version.
11 This program is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with this program. If not, see <http://www.gnu.org/licenses/>. */
19 /* Written by Paul Eggert, David MacKenzie, and Jim Meyering. */
30 #define _(msgid) gettext (msgid)
32 #include "dirchownmod.h"
36 #include "mkancesdirs.h"
40 # define HAVE_FCHMOD false
43 /* Ensure that the directory DIR exists.
45 WD is the working directory, as in savewd.c.
47 If MAKE_ANCESTOR is not null, create any ancestor directories that
48 don't already exist, by invoking MAKE_ANCESTOR (DIR, ANCESTOR, OPTIONS).
49 This function should return zero if successful, -1 (setting errno)
50 otherwise. In this case, DIR may be modified by storing '\0' bytes
51 into it, to access the ancestor directories, and this modification
52 is retained on return if the ancestor directories could not be
55 Create DIR as a new directory with using mkdir with permissions
56 MODE. It is also OK if MAKE_ANCESTOR is not null and a
57 directory DIR already exists.
59 Call ANNOUNCE (DIR, OPTIONS) just after successfully making DIR,
60 even if some of the following actions fail.
62 Set DIR's owner to OWNER and group to GROUP, but leave the owner
63 alone if OWNER is (uid_t) -1, and similarly for GROUP.
65 Set DIR's mode bits to MODE, except preserve any of the bits that
66 correspond to zero bits in MODE_BITS. In other words, MODE_BITS is
67 a mask that specifies which of DIR's mode bits should be set or
68 cleared. MODE should be a subset of MODE_BITS, which in turn
69 should be a subset of CHMOD_MODE_BITS. Changing the mode in this
70 way is necessary if DIR already existed or if MODE and MODE_BITS
71 specify non-permissions bits like S_ISUID.
73 However, if PRESERVE_EXISTING is true and DIR already exists,
74 do not attempt to set DIR's ownership and file mode bits.
76 This implementation assumes the current umask is zero.
78 Return true if DIR exists as a directory with the proper ownership
79 and file mode bits when done, or if a child process has been
80 dispatched to do the real work (though the child process may not
81 have finished yet -- it is the caller's responsibility to handle
82 this). Report a diagnostic and return false on failure, storing
83 '\0' into *DIR if an ancestor directory had problems. */
86 make_dir_parents (char *dir,
88 int (*make_ancestor) (char const *, char const *, void *),
91 void (*announce) (char const *, void *),
95 bool preserve_existing)
97 int mkdir_errno = (IS_ABSOLUTE_FILE_NAME (dir) ? 0 : savewd_errno (wd));
101 ptrdiff_t prefix_len = 0;
102 int savewd_chdir_options = (HAVE_FCHMOD ? SAVEWD_CHDIR_SKIP_READABLE : 0);
106 prefix_len = mkancesdirs (dir, wd, make_ancestor, options);
117 /* If the ownership might change, or if the directory will be
118 writeable to other users and its special mode bits may
119 change after the directory is created, create it with
120 more restrictive permissions at first, so unauthorized
121 users cannot nip in before the directory is ready. */
122 bool keep_owner = owner == (uid_t) -1 && group == (gid_t) -1;
123 bool keep_special_mode_bits =
124 ((mode_bits & (S_ISUID | S_ISGID)) | (mode & S_ISVTX)) == 0;
125 mode_t mkdir_mode = mode;
127 mkdir_mode &= ~ (S_IRWXG | S_IRWXO);
128 else if (! keep_special_mode_bits)
129 mkdir_mode &= ~ (S_IWGRP | S_IWOTH);
131 if (mkdir (dir + prefix_len, mkdir_mode) == 0)
133 announce (dir, options);
134 preserve_existing = keep_owner & keep_special_mode_bits;
135 savewd_chdir_options |=
136 (SAVEWD_CHDIR_NOFOLLOW
137 | (mode & S_IRUSR ? SAVEWD_CHDIR_READABLE : 0));
145 if (preserve_existing)
149 || (mkdir_errno != ENOENT && make_ancestor
150 && stat (dir + prefix_len, &st) == 0
151 && S_ISDIR (st.st_mode)))
158 savewd_chdir (wd, dir + prefix_len,
159 savewd_chdir_options, open_result);
160 if (chdir_result < -1)
164 bool chdir_ok = (chdir_result == 0);
165 int chdir_errno = errno;
166 int fd = open_result[0];
167 bool chdir_failed_unexpectedly =
169 && ((! chdir_ok && (mode & S_IXUSR))
170 || (fd < 0 && (mode & S_IRUSR))));
172 if (chdir_failed_unexpectedly)
174 /* No need to save errno here; it's irrelevant. */
180 char const *subdir = (chdir_ok ? "." : dir + prefix_len);
181 if (dirchownmod (fd, subdir, mkdir_mode, owner, group,
188 || (mkdir_errno != ENOENT && make_ancestor
189 && errno != ENOTDIR))
192 (! chdir_failed_unexpectedly ? errno
193 : ! chdir_ok && (mode & S_IXUSR) ? chdir_errno
196 ? "cannot change permissions of %s"
197 : "cannot change owner and permissions of %s"),
206 error (0, mkdir_errno, _("cannot create directory %s"), quote (dir));