src/basic/mkdir.c

   1 /***
   2   This file is part of systemd.
   3
   4   Copyright 2010 Lennart Poettering
   5
   6   systemd is free software; you can redistribute it and/or modify it
   7   under the terms of the GNU Lesser General Public License as published by
   8   the Free Software Foundation; either version 2.1 of the License, or
   9   (at your option) any later version.
  10
  11   systemd is distributed in the hope that it will be useful, but
  12   WITHOUT ANY WARRANTY; without even the implied warranty of
  13   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
  14   Lesser General Public License for more details.
  15
  16   You should have received a copy of the GNU Lesser General Public License
  17   along with systemd; If not, see <http://www.gnu.org/licenses/>.
  18 ***/
  19
  20 #include <errno.h>
  21 #include <stdbool.h>
  22 #include <string.h>
  23 #include <sys/stat.h>
  24
  25 #include "alloc-util.h"
  26 #include "fs-util.h"
  27 #include "macro.h"
  28 #include "mkdir.h"
  29 #include "path-util.h"
  30 #include "stat-util.h"
  31 #include "user-util.h"
  32
  33 int mkdir_safe_internal(const char *path, mode_t mode, uid_t uid, gid_t gid, bool follow_symlink, mkdir_func_t _mkdir) {
  34         struct stat st;
  35         int r;
  36
  37         if (_mkdir(path, mode) >= 0) {
  38                 r = chmod_and_chown(path, mode, uid, gid);
  39                 if (r < 0)
  40                         return r;
  41         }
  42
  43         if (lstat(path, &st) < 0)
  44                 return -errno;
  45
  46         if (follow_symlink && S_ISLNK(st.st_mode)) {
  47                 _cleanup_free_ char *p = NULL;
  48
  49                 r = chase_symlinks(path, NULL, CHASE_NONEXISTENT, &p);
  50                 if (r < 0)
  51                         return r;
  52                 if (r == 0)
  53                         return mkdir_safe_internal(p, mode, uid, gid, false, _mkdir);
  54
  55                 if (lstat(p, &st) < 0)
  56                         return -errno;
  57         }
  58
  59         if ((st.st_mode & 0007) > (mode & 0007) ||
  60             (st.st_mode & 0070) > (mode & 0070) ||
  61             (st.st_mode & 0700) > (mode & 0700) ||
  62             (uid != UID_INVALID && st.st_uid != uid) ||
  63             (gid != GID_INVALID && st.st_gid != gid) ||
  64             !S_ISDIR(st.st_mode))
  65                 return -EEXIST;
  66
  67         return 0;
  68 }
  69
  70 int mkdir_safe(const char *path, mode_t mode, uid_t uid, gid_t gid, bool follow_symlink) {
  71         return mkdir_safe_internal(path, mode, uid, gid, follow_symlink, mkdir);
  72 }
  73
  74 int mkdir_parents_internal(const char *prefix, const char *path, mode_t mode, mkdir_func_t _mkdir) {
  75         const char *p, *e;
  76         int r;
  77
  78         assert(path);
  79
  80         if (prefix && !path_startswith(path, prefix))
  81                 return -ENOTDIR;
  82
  83         /* return immediately if directory exists */
  84         e = strrchr(path, '/');
  85         if (!e)
  86                 return -EINVAL;
  87
  88         if (e == path)
  89                 return 0;
  90
  91         p = strndupa(path, e - path);
  92         r = is_dir(p, true);
  93         if (r > 0)
  94                 return 0;
  95         if (r == 0)
  96                 return -ENOTDIR;
  97
  98         /* create every parent directory in the path, except the last component */
  99         p = path + strspn(path, "/");
 100         for (;;) {
 101                 char t[strlen(path) + 1];
 102
 103                 e = p + strcspn(p, "/");
 104                 p = e + strspn(e, "/");
 105
 106                 /* Is this the last component? If so, then we're
 107                  * done */
 108                 if (*p == 0)
 109                         return 0;
 110
 111                 memcpy(t, path, e - path);
 112                 t[e-path] = 0;
 113
 114                 if (prefix && path_startswith(prefix, t))
 115                         continue;
 116
 117                 r = _mkdir(t, mode);
 118                 if (r < 0 && errno != EEXIST)
 119                         return -errno;
 120         }
 121 }
 122
 123 int mkdir_parents(const char *path, mode_t mode) {
 124         return mkdir_parents_internal(NULL, path, mode, mkdir);
 125 }
 126
 127 int mkdir_p_internal(const char *prefix, const char *path, mode_t mode, mkdir_func_t _mkdir) {
 128         int r;
 129
 130         /* Like mkdir -p */
 131
 132         r = mkdir_parents_internal(prefix, path, mode, _mkdir);
 133         if (r < 0)
 134                 return r;
 135
 136         r = _mkdir(path, mode);
 137         if (r < 0 && (errno != EEXIST || is_dir(path, true) <= 0))
 138                 return -errno;
 139
 140         return 0;
 141 }
 142
 143 int mkdir_p(const char *path, mode_t mode) {
 144         return mkdir_p_internal(NULL, path, mode, mkdir);
 145 }