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/* Mar 5, 2003    Manuel Novoa III
  10 *
  11 * This is the main work function for the 'mkdir' applet.  As such, it
  12 * strives to be SUSv3 compliant in it's behaviour when recursively
  13 * making missing parent dirs, and in it's mode setting of the final
  14 * directory 'path'.
  15 *
  16 * To recursively build all missing intermediate directories, make
  17 * sure that (flags & FILEUTILS_RECUR) is non-zero.  Newly created
  18 * intermediate directories will have at least u+wx perms.
  19 *
  20 * To set specific permissions on 'path', pass the appropriate 'mode'
  21 * val.  Otherwise, pass -1 to get default permissions.
  22 */
  23#include "libbb.h"
  24
  25/* This function is used from NOFORK applets. It must not allocate anything */
  26
  27int FAST_FUNC bb_make_directory(char *path, long mode, int flags)
  28{
  29        mode_t cur_mask;
  30        mode_t org_mask;
  31        const char *fail_msg;
  32        char *s;
  33        char c;
  34        struct stat st;
  35
  36        /* "path" can be a result of dirname().
  37         * dirname("no_slashes") returns ".", possibly read-only.
  38         * musl dirname() can return read-only "/" too.
  39         * We need writable string. And for "/", "." (and ".."?)
  40         * nothing needs to be created anyway.
  41         */
  42        if (LONE_CHAR(path, '/'))
  43                return 0;
  44        if (path[0] == '.') {
  45                if (path[1] == '\0')
  46                        return 0; /* "." */
  47//              if (path[1] == '.' && path[2] == '\0')
  48//                      return 0; /* ".." */
  49        }
  50
  51        org_mask = cur_mask = (mode_t)-1L;
  52        s = path;
  53        while (1) {
  54                c = '\0';
  55
  56                if (flags & FILEUTILS_RECUR) {  /* Get the parent */
  57                        /* Bypass leading non-'/'s and then subsequent '/'s */
  58                        while (*s) {
  59                                if (*s == '/') {
  60                                        do {
  61                                                ++s;
  62                                        } while (*s == '/');
  63                                        c = *s; /* Save the current char */
  64                                        *s = '\0'; /* and replace it with nul */
  65                                        break;
  66                                }
  67                                ++s;
  68                        }
  69                }
  70
  71                if (c != '\0') {
  72                        /* Intermediate dirs: must have wx for user */
  73                        if (cur_mask == (mode_t)-1L) { /* wasn't done yet? */
  74                                mode_t new_mask;
  75                                org_mask = umask(0);
  76                                cur_mask = 0;
  77                                /* Clear u=wx in umask - this ensures
  78                                 * they won't be cleared on mkdir */
  79                                new_mask = (org_mask & ~(mode_t)0300);
  80                                //bb_error_msg("org_mask:%o cur_mask:%o", org_mask, new_mask);
  81                                if (new_mask != cur_mask) {
  82                                        cur_mask = new_mask;
  83                                        umask(new_mask);
  84                                }
  85                        }
  86                } else {
  87                        /* Last component: uses original umask */
  88                        //bb_error_msg("1 org_mask:%o", org_mask);
  89                        if (org_mask != cur_mask) {
  90                                cur_mask = org_mask;
  91                                umask(org_mask);
  92                        }
  93                }
  94
  95                //bb_error_msg("mkdir '%s'", path);
  96                if (mkdir(path, 0777) < 0) {
  97                        /* If we failed for any other reason than the directory
  98                         * already exists, output a diagnostic and return -1 */
  99                        if ((errno != EEXIST && errno != EISDIR)
 100                         || !(flags & FILEUTILS_RECUR)
 101                         || ((stat(path, &st) < 0) || !S_ISDIR(st.st_mode))
 102                        ) {
 103                                fail_msg = "create";
 104                                break;
 105                        }
 106                        /* Since the directory exists, don't attempt to change
 107                         * permissions if it was the full target.  Note that
 108                         * this is not an error condition. */
 109                        if (!c) {
 110                                goto ret0;
 111                        }
 112                } else {
 113                        if (flags & FILEUTILS_VERBOSE) {
 114                                printf("created directory: '%s'\n", path);
 115                        }
 116                }
 117
 118                if (!c) {
 119                        /* Done.  If necessary, update perms on the newly
 120                         * created directory.  Failure to update here _is_
 121                         * an error. */
 122                        if (mode != -1) {
 123                                //bb_error_msg("chmod 0%03lo mkdir '%s'", mode, path);
 124                                if (chmod(path, mode) < 0) {
 125                                        fail_msg = "set permissions of";
 126                                        if (flags & FILEUTILS_IGNORE_CHMOD_ERR) {
 127                                                flags = 0;
 128                                                goto print_err;
 129                                        }
 130                                        break;
 131                                }
 132                        }
 133                        goto ret0;
 134                }
 135
 136                /* Remove any inserted nul from the path (recursive mode) */
 137                *s = c;
 138        } /* while (1) */
 139
 140        flags = -1;
 141 print_err:
 142        bb_perror_msg("can't %s directory '%s'", fail_msg, path);
 143        goto ret;
 144 ret0:
 145        flags = 0;
 146 ret:
 147        //bb_error_msg("2 org_mask:%o", org_mask);
 148        if (org_mask != cur_mask)
 149                umask(org_mask);
 150        return flags;
 151}
 152