LXR busybox/libbb/make

   1/* vi: set sw=4 ts=4: */
   2/*
   3 * parse_mode implementation for busybox
   4 *
   5 * Copyright (C) 2003  Manuel Novoa III  <mjn3@codepoet.org>
   6 *
   7 * Licensed under GPLv2 or later, see file LICENSE in this source tree.
   8 */
   9
  10/* Mar 5, 2003    Manuel Novoa III
  11 *
  12 * This is the main work function for the 'mkdir' applet.  As such, it
  13 * strives to be SUSv3 compliant in it's behaviour when recursively
  14 * making missing parent dirs, and in it's mode setting of the final
  15 * directory 'path'.
  16 *
  17 * To recursively build all missing intermediate directories, make
  18 * sure that (flags & FILEUTILS_RECUR) is non-zero.  Newly created
  19 * intermediate directories will have at least u+wx perms.
  20 *
  21 * To set specific permissions on 'path', pass the appropriate 'mode'
  22 * val.  Otherwise, pass -1 to get default permissions.
  23 */
  24
  25#include "libbb.h"
  26
  27/* This function is used from NOFORK applets. It must not allocate anything */
  28
  29int FAST_FUNC bb_make_directory(char *path, long mode, int flags)
  30{
  31        mode_t cur_mask;
  32        mode_t org_mask;
  33        const char *fail_msg;
  34        char *s;
  35        char c;
  36        struct stat st;
  37
  38        /* "path" can be a result of dirname().
  39         * dirname("no_slashes") returns ".", possibly read-only.
  40         * musl dirname() can return read-only "/" too.
  41         * We need writable string. And for "/", "." (and ".."?)
  42         * nothing needs to be created anyway.
  43         */
  44        if (LONE_CHAR(path, '/'))
  45                return 0;
  46        if (path[0] == '.') {
  47                if (path[1] == '\0')
  48                        return 0; /* "." */
  49//              if (path[1] == '.' && path[2] == '\0')
  50//                      return 0; /* ".." */
  51        }
  52
  53        org_mask = cur_mask = (mode_t)-1L;
  54        s = path;
  55        while (1) {
  56                c = '\0';
  57
  58                if (flags & FILEUTILS_RECUR) {  /* Get the parent */
  59                        /* Bypass leading non-'/'s and then subsequent '/'s */
  60                        while (*s) {
  61                                if (*s == '/') {
  62                                        do {
  63                                                ++s;
  64                                        } while (*s == '/');
  65                                        c = *s; /* Save the current char */
  66                                        *s = '\0'; /* and replace it with nul */
  67                                        break;
  68                                }
  69                                ++s;
  70                        }
  71                }
  72
  73                if (c != '\0') {
  74                        /* Intermediate dirs: must have wx for user */
  75                        if (cur_mask == (mode_t)-1L) { /* wasn't done yet? */
  76                                mode_t new_mask;
  77                                org_mask = umask(0);
  78                                cur_mask = 0;
  79                                /* Clear u=wx in umask - this ensures
  80                                 * they won't be cleared on mkdir */
  81                                new_mask = (org_mask & ~(mode_t)0300);
  82                                //bb_error_msg("org_mask:%o cur_mask:%o", org_mask, new_mask);
  83                                if (new_mask != cur_mask) {
  84                                        cur_mask = new_mask;
  85                                        umask(new_mask);
  86                                }
  87                        }
  88                } else {
  89                        /* Last component: uses original umask */
  90                        //bb_error_msg("1 org_mask:%o", org_mask);
  91                        if (org_mask != cur_mask) {
  92                                cur_mask = org_mask;
  93                                umask(org_mask);
  94                        }
  95                }
  96
  97                if (mkdir(path, 0777) < 0) {
  98                        /* If we failed for any other reason than the directory
  99                         * already exists, output a diagnostic and return -1 */
 100                        if ((errno != EEXIST && errno != EISDIR)
 101                         || !(flags & FILEUTILS_RECUR)
 102                         || ((stat(path, &st) < 0) || !S_ISDIR(st.st_mode))
 103                        ) {
 104                                fail_msg = "create";
 105                                break;
 106                        }
 107                        /* Since the directory exists, don't attempt to change
 108                         * permissions if it was the full target.  Note that
 109                         * this is not an error condition. */
 110                        if (!c) {
 111                                goto ret0;
 112                        }
 113                } else {
 114                        if (flags & FILEUTILS_VERBOSE) {
 115                                printf("created directory: '%s'\n", path);
 116                        }
 117                }
 118
 119                if (!c) {
 120                        /* Done.  If necessary, update perms on the newly
 121                         * created directory.  Failure to update here _is_
 122                         * an error. */
 123                        if ((mode != -1) && (chmod(path, mode) < 0)) {
 124                                fail_msg = "set permissions of";
 125                                if (flags & FILEUTILS_IGNORE_CHMOD_ERR) {
 126                                        flags = 0;
 127                                        goto print_err;
 128                                }
 129                                break;
 130                        }
 131                        goto ret0;
 132                }
 133
 134                /* Remove any inserted nul from the path (recursive mode) */
 135                *s = c;
 136        } /* while (1) */
 137
 138        flags = -1;
 139 print_err:
 140        bb_perror_msg("can't %s directory '%s'", fail_msg, path);
 141        goto ret;
 142 ret0:
 143        flags = 0;
 144 ret:
 145        //bb_error_msg("2 org_mask:%o", org_mask);
 146        if (org_mask != cur_mask)
 147                umask(org_mask);
 148        return flags;
 149}
 150