[Sommaire] [Imprimer]

   1  <?php
   2  // $Id: file.inc,v 1.90.2.1 2007/05/31 05:48:58 drumm Exp $
   3  
   4  /**
   5   * @file
   6   * API for handling file uploads and server file management.
   7   */
   8  
   9  /**
  10   * @defgroup file File interface
  11   * @{
  12   * Common file handling functions.
  13   */
  14  
  15  define('FILE_DOWNLOADS_PUBLIC', 1);
  16  define('FILE_DOWNLOADS_PRIVATE', 2);
  17  define('FILE_CREATE_DIRECTORY', 1);
  18  define('FILE_MODIFY_PERMISSIONS', 2);
  19  define('FILE_EXISTS_RENAME', 0);
  20  define('FILE_EXISTS_REPLACE', 1);
  21  define('FILE_EXISTS_ERROR', 2);
  22  
  23  /**
  24   * Create the download path to a file.
  25   *
  26   * @param $path A string containing the path of the file to generate URL for.
  27   * @return A string containing a URL that can be used to download the file.
  28   */
  29  function file_create_url($path) {
  30    // Strip file_directory_path from $path. We only include relative paths in urls.
  31    if (strpos($path, file_directory_path() . '/') === 0) {
  32      $path = trim(substr($path, strlen(file_directory_path())), '\\/');
  33    }
  34    switch (variable_get('file_downloads', FILE_DOWNLOADS_PUBLIC)) {
  35      case FILE_DOWNLOADS_PUBLIC:
  36        return $GLOBALS['base_url'] .'/'. file_directory_path() .'/'. str_replace('\\', '/', $path);
  37      case FILE_DOWNLOADS_PRIVATE:
  38        return url('system/files/'. $path, NULL, NULL, TRUE);
  39    }
  40  }
  41  
  42  /**
  43   * Make sure the destination is a complete path and resides in the file system
  44   * directory, if it is not prepend the file system directory.
  45   *
  46   * @param $dest A string containing the path to verify. If this value is
  47   *   omitted, Drupal's 'files' directory will be used.
  48   * @return A string containing the path to file, with file system directory
  49   *   appended if necessary, or FALSE if the path is invalid (i.e. outside the
  50   *   configured 'files' or temp directories).
  51   */
  52  function file_create_path($dest = 0) {
  53    $file_path = file_directory_path();
  54    if (!$dest) {
  55      return $file_path;
  56    }
  57    // file_check_location() checks whether the destination is inside the Drupal files directory.
  58    if (file_check_location($dest, $file_path)) {
  59      return $dest;
  60    }
  61    // check if the destination is instead inside the Drupal temporary files directory.
  62    else if (file_check_location($dest, file_directory_temp())) {
  63      return $dest;
  64    }
  65    // Not found, try again with prefixed directory path.
  66    else if (file_check_location($file_path . '/' . $dest, $file_path)) {
  67      return $file_path . '/' . $dest;
  68    }
  69    // File not found.
  70    return FALSE;
  71  }
  72  
  73  /**
  74   * Check that the directory exists and is writable. Directories need to
  75   * have execute permissions to be considered a directory by FTP servers, etc.
  76   *
  77   * @param $directory A string containing the name of a directory path.
  78   * @param $mode A Boolean value to indicate if the directory should be created
  79   *   if it does not exist or made writable if it is read-only.
  80   * @param $form_item An optional string containing the name of a form item that
  81   *   any errors will be attached to. This is useful for settings forms that
  82   *   require the user to specify a writable directory. If it can't be made to
  83   *   work, a form error will be set preventing them from saving the settings.
  84   * @return FALSE when directory not found, or TRUE when directory exists.
  85   */
  86  function file_check_directory(&$directory, $mode = 0, $form_item = NULL) {
  87    $directory = rtrim($directory, '/\\');
  88  
  89    // Check if directory exists.
  90    if (!is_dir($directory)) {
  91      if (($mode & FILE_CREATE_DIRECTORY) && @mkdir($directory)) {
  92        drupal_set_message(t('The directory %directory has been created.', array('%directory' => $directory)));
  93        @chmod($directory, 0775); // Necessary for non-webserver users.
  94      }
  95      else {
  96        if ($form_item) {
  97          form_set_error($form_item, t('The directory %directory does not exist.', array('%directory' => $directory)));
  98        }
  99        return FALSE;
 100      }
 101    }
 102  
 103    // Check to see if the directory is writable.
 104    if (!is_writable($directory)) {
 105      if (($mode & FILE_MODIFY_PERMISSIONS) && @chmod($directory, 0775)) {
 106        drupal_set_message(t('The permissions of directory %directory have been changed to make it writable.', array('%directory' => $directory)));
 107      }
 108      else {
 109        form_set_error($form_item, t('The directory %directory is not writable', array('%directory' => $directory)));
 110        watchdog('file system', t('The directory %directory is not writable, because it does not have the correct permissions set.', array('%directory' => $directory)), WATCHDOG_ERROR);
 111        return FALSE;
 112      }
 113    }
 114  
 115    if ((file_directory_path() == $directory || file_directory_temp() == $directory) && !is_file("$directory/.htaccess")) {
 116      $htaccess_lines = "SetHandler Drupal_Security_Do_Not_Remove_See_SA_2006_006\nOptions None\nOptions +FollowSymLinks";
 117      if (($fp = fopen("$directory/.htaccess", 'w')) && fputs($fp, $htaccess_lines)) {
 118        fclose($fp);
 119        chmod($directory .'/.htaccess', 0664);
 120      }
 121      else {
 122        $message = t("Security warning: Couldn't write .htaccess file. Please create a .htaccess file in your %directory directory which contains the following lines: <code>!htaccess</code>", array('%directory' => $directory, '!htaccess' => '<br />'. nl2br(check_plain($htaccess_lines))));
 123        form_set_error($form_item, $message);
 124        watchdog('security', $message, WATCHDOG_ERROR);
 125      }
 126    }
 127  
 128    return TRUE;
 129  }
 130  
 131  /**
 132   * Checks path to see if it is a directory, or a dir/file.
 133   *
 134   * @param $path A string containing a file path. This will be set to the
 135   *   directory's path.
 136   * @return If the directory is not in a Drupal writable directory, FALSE is
 137   *   returned. Otherwise, the base name of the path is returned.
 138   */
 139  function file_check_path(&$path) {
 140    // Check if path is a directory.
 141    if (file_check_directory($path)) {
 142      return '';
 143    }
 144  
 145    // Check if path is a possible dir/file.
 146    $filename = basename($path);
 147    $path = dirname($path);
 148    if (file_check_directory($path)) {
 149      return $filename;
 150    }
 151  
 152    return FALSE;
 153  }
 154  
 155  
 156  /**
 157   * Check if $source is a valid file upload. If so, move the file to Drupal's tmp dir
 158   * and return it as an object.
 159   *
 160   * The use of SESSION['file_uploads'] should probably be externalized to upload.module
 161   *
 162   * @todo Rename file_check_upload to file_prepare upload.
 163   * @todo Refactor or merge file_save_upload.
 164   * @todo Extenalize SESSION['file_uploads'] to modules.
 165   *
 166   * @param $source An upload source (the name of the upload form item), or a file
 167   * @return FALSE for an invalid file or upload. A file object for valid uploads/files.
 168   *
 169   */
 170  
 171  function file_check_upload($source = 'upload') {
 172    // Cache for uploaded files. Since the data in _FILES is modified
 173    // by this function, we cache the result.
 174    static $upload_cache;
 175  
 176    // Test source to see if it is an object.
 177    if (is_object($source)) {
 178  
 179      // Validate the file path if an object was passed in instead of
 180      // an upload key.
 181      if (is_file($source->filepath)) {
 182        return $source;
 183      }
 184      else {
 185        return FALSE;
 186      }
 187    }
 188  
 189    // Return cached objects without processing since the file will have
 190    // already been processed and the paths in _FILES will be invalid.
 191    if (isset($upload_cache[$source])) {
 192      return $upload_cache[$source];
 193    }
 194  
 195    // If a file was uploaded, process it.
 196    if ($_FILES["files"]["name"][$source] && is_uploaded_file($_FILES["files"]["tmp_name"][$source])) {
 197  
 198      // Check for file upload errors and return FALSE if a
 199      // lower level system error occurred.
 200      switch ($_FILES["files"]["error"][$source]) {
 201  
 202        // @see http://php.net/manual/en/features.file-upload.errors.php
 203        case UPLOAD_ERR_OK:
 204          break;
 205  
 206        case UPLOAD_ERR_INI_SIZE:
 207        case UPLOAD_ERR_FORM_SIZE:
 208          drupal_set_message(t('The file %file could not be saved, because it exceeds the maximum allowed size for uploads.', array('%file' => $source)), 'error');
 209          return 0;
 210  
 211        case UPLOAD_ERR_PARTIAL:
 212        case UPLOAD_ERR_NO_FILE:
 213          drupal_set_message(t('The file %file could not be saved, because the upload did not complete.', array('%file' => $source)), 'error');
 214          return 0;
 215  
 216        // Unknown error
 217        default:
 218          drupal_set_message(t('The file %file could not be saved. An unknown error has occurred.', array('%file' => $source)),'error');
 219          return 0;
 220      }
 221  
 222      // Begin building file object.
 223      $file = new stdClass();
 224      $file->filename = trim(basename($_FILES["files"]["name"][$source]), '.');
 225  
 226      // Create temporary name/path for newly uploaded files.
 227      $file->filepath = tempnam(file_directory_temp(), 'tmp_');
 228  
 229      $file->filemime = $_FILES["files"]["type"][$source];
 230  
 231      // Rename potentially executable files, to help prevent exploits.
 232      if (preg_match('/\.(php|pl|py|cgi|asp|js)$/i', $file->filename) && (substr($file->filename, -4) != '.txt')) {
 233        $file->filemime = 'text/plain';
 234        $file->filepath .= '.txt';
 235        $file->filename .= '.txt';
 236      }
 237  
 238      // Move uploaded files from php's upload_tmp_dir to Drupal's file temp.
 239      // This overcomes open_basedir restrictions for future file operations.
 240      if (!move_uploaded_file($_FILES["files"]["tmp_name"][$source], $file->filepath)) {
 241        drupal_set_message(t('File upload error. Could not move uploaded file.'));
 242        watchdog('file', t('Upload Error. Could not move uploaded file (%file) to destination (%destination).', array('%file' => $_FILES["files"]["tmp_name"][$source], '%destination' => $file->filepath)));
 243        return FALSE;
 244      }
 245  
 246      $file->filesize = $_FILES["files"]["size"][$source];
 247      $file->source = $source;
 248  
 249      // Add processed file to the cache.
 250      $upload_cache[$source] = $file;
 251      return $file;
 252    }
 253  
 254    else {
 255      // In case of previews return previous file object.
 256      if (file_exists($_SESSION['file_uploads'][$source]->filepath)) {
 257        return $_SESSION['file_uploads'][$source];
 258      }
 259    }
 260    // If nothing was done, return FALSE.
 261    return FALSE;
 262  }
 263  
 264  /**
 265   * Check if a file is really located inside $directory. Should be used to make
 266   * sure a file specified is really located within the directory to prevent
 267   * exploits.
 268   *
 269   * @code
 270   *   // Returns FALSE:
 271   *   file_check_location('/www/example.com/files/../../../etc/passwd', '/www/example.com/files');
 272   * @endcode
 273   *
 274   * @param $source A string set to the file to check.
 275   * @param $directory A string where the file should be located.
 276   * @return 0 for invalid path or the real path of the source.
 277   */
 278  function file_check_location($source, $directory = '') {
 279    $check = realpath($source);
 280    if ($check) {
 281      $source = $check;
 282    }
 283    else {
 284      // This file does not yet exist
 285      $source = realpath(dirname($source)) .'/'. basename($source);
 286    }
 287    $directory = realpath($directory);
 288    if ($directory && strpos($source, $directory) !== 0) {
 289      return 0;
 290    }
 291    return $source;
 292  }
 293  
 294  /**
 295   * Copies a file to a new location. This is a powerful function that in many ways
 296   * performs like an advanced version of copy().
 297   * - Checks if $source and $dest are valid and readable/writable.
 298   * - Performs a file copy if $source is not equal to $dest.
 299   * - If file already exists in $dest either the call will error out, replace the
 300   *   file or rename the file based on the $replace parameter.
 301   *
 302   * @param $source A string specifying the file location of the original file.
 303   *   This parameter will contain the resulting destination filename in case of
 304   *   success.
 305   * @param $dest A string containing the directory $source should be copied to.
 306   *   If this value is omitted, Drupal's 'files' directory will be used.
 307   * @param $replace Replace behavior when the destination file already exists.
 308   *   - FILE_EXISTS_REPLACE - Replace the existing file
 309   *   - FILE_EXISTS_RENAME - Append _{incrementing number} until the filename is unique
 310   *   - FILE_EXISTS_ERROR - Do nothing and return FALSE.
 311   * @return True for success, FALSE for failure.
 312   */
 313  function file_copy(&$source, $dest = 0, $replace = FILE_EXISTS_RENAME) {
 314    $dest = file_create_path($dest);
 315  
 316    $directory = $dest;
 317    $basename = file_check_path($directory);
 318  
 319    // Make sure we at least have a valid directory.
 320    if ($basename === FALSE) {
 321      $source = is_object($source) ? $source->filepath : $source;
 322      drupal_set_message(t('The selected file %file could not be uploaded, because the destination %directory is not properly configured.', array('%file' => $source, '%directory' => $dest)), 'error');
 323      watchdog('file system', t('The selected file %file could not be uploaded, because the destination %directory could not be found, or because its permissions do not allow the file to be written.', array('%file' => $source, '%directory' => $dest)), WATCHDOG_ERROR);
 324      return 0;
 325    }
 326  
 327    // Process a file upload object.
 328    if (is_object($source)) {
 329      $file = $source;
 330      $source = $file->filepath;
 331      if (!$basename) {
 332        $basename = $file->filename;
 333      }
 334    }
 335  
 336    $source = realpath($source);
 337    if (!file_exists($source)) {
 338      drupal_set_message(t('The selected file %file could not be copied, because no file by that name exists. Please check that you supplied the correct filename.', array('%file' => $source)), 'error');
 339      return 0;
 340    }
 341  
 342    // If the destination file is not specified then use the filename of the source file.
 343    $basename = $basename ? $basename : basename($source);
 344    $dest = $directory .'/'. $basename;
 345  
 346    // Make sure source and destination filenames are not the same, makes no sense
 347    // to copy it if they are. In fact copying the file will most likely result in
 348    // a 0 byte file. Which is bad. Real bad.
 349    if ($source != realpath($dest)) {
 350      if (file_exists($dest)) {
 351        switch ($replace) {
 352          case FILE_EXISTS_RENAME:
 353            // Destination file already exists and we can't replace is so we try and
 354            // and find a new filename.
 355            if ($pos = strrpos($basename, '.')) {
 356              $name = substr($basename, 0, $pos);
 357              $ext = substr($basename, $pos);
 358            }
 359            else {
 360              $name = $basename;
 361            }
 362  
 363            $counter = 0;
 364            do {
 365              $dest = $directory .'/'. $name .'_'. $counter++ . $ext;
 366            } while (file_exists($dest));
 367            break;
 368  
 369          case FILE_EXISTS_ERROR:
 370            drupal_set_message(t('The selected file %file could not be copied, because a file by that name already exists in the destination.', array('%file' => $source)), 'error');
 371            return 0;
 372        }
 373      }
 374  
 375      if (!@copy($source, $dest)) {
 376        drupal_set_message(t('The selected file %file could not be copied.', array('%file' => $source)), 'error');
 377        return 0;
 378      }
 379  
 380      // Give everyone read access so that FTP'd users or
 381      // non-webserver users can see/read these files.
 382      @chmod($dest, 0664);
 383    }
 384  
 385    if (is_object($file)) {
 386      $file->filename = $basename;
 387      $file->filepath = $dest;
 388      $source = $file;
 389    }
 390    else {
 391      $source = $dest;
 392    }
 393  
 394    return 1; // Everything went ok.
 395  }
 396  
 397  /**
 398   * Moves a file to a new location.
 399   * - Checks if $source and $dest are valid and readable/writable.
 400   * - Performs a file move if $source is not equal to $dest.
 401   * - If file already exists in $dest either the call will error out, replace the
 402   *   file or rename the file based on the $replace parameter.
 403   *
 404   * @param $source A string specifying the file location of the original file.
 405   *   This parameter will contain the resulting destination filename in case of
 406   *   success.
 407   * @param $dest A string containing the directory $source should be copied to.
 408   *   If this value is omitted, Drupal's 'files' directory will be used.
 409   * @param $replace Replace behavior when the destination file already exists.
 410   *   - FILE_EXISTS_REPLACE - Replace the existing file
 411   *   - FILE_EXISTS_RENAME - Append _{incrementing number} until the filename is unique
 412   *   - FILE_EXISTS_ERROR - Do nothing and return FALSE.
 413   * @return True for success, FALSE for failure.
 414   */
 415  function file_move(&$source, $dest = 0, $replace = FILE_EXISTS_RENAME) {
 416  
 417    $path_original = is_object($source) ? $source->filepath : $source;
 418  
 419    if (file_copy($source, $dest, $replace)) {
 420      $path_current = is_object($source) ? $source->filepath : $source;
 421  
 422      if ($path_original == $path_current || file_delete($path_original)) {
 423        return 1;
 424      }
 425      drupal_set_message(t('The removal of the original file %file has failed.', array('%file' => $path_original)), 'error');
 426    }
 427    return 0;
 428  }
 429  
 430  /**
 431   * Create a full file path from a directory and filename. If a file with the
 432   * specified name already exists, an alternative will be used.
 433   *
 434   * @param $basename string filename
 435   * @param $directory string directory
 436   * @return
 437   */
 438  function file_create_filename($basename, $directory) {
 439    $dest = $directory .'/'. $basename;
 440  
 441    if (file_exists($dest)) {
 442      // Destination file already exists, generate an alternative.
 443      if ($pos = strrpos($basename, '.')) {
 444        $name = substr($basename, 0, $pos);
 445        $ext = substr($basename, $pos);
 446      }
 447      else {
 448        $name = $basename;
 449      }
 450  
 451      $counter = 0;
 452      do {
 453        $dest = $directory .'/'. $name .'_'. $counter++ . $ext;
 454      } while (file_exists($dest));
 455    }
 456  
 457    return $dest;
 458  }
 459  
 460  /**
 461   * Delete a file.
 462   *
 463   * @param $path A string containing a file path.
 464   * @return True for success, FALSE for failure.
 465   */
 466  function file_delete($path) {
 467    if (is_file($path)) {
 468      return unlink($path);
 469    }
 470  }
 471  
 472  /**
 473   * Saves a file upload to a new location. The source file is validated as a
 474   * proper upload and handled as such.
 475   *
 476   * @param $source A string specifying the name of the upload field to save.
 477   *   This parameter will contain the resulting destination filename in case of
 478   *   success.
 479   * @param $dest A string containing the directory $source should be copied to,
 480   *   will use the temporary directory in case no other value is set.
 481   * @param $replace A boolean, set to TRUE if the destination should be replaced
 482   *   when in use, but when FALSE append a _X to the filename.
 483   * @return An object containing file info or 0 in case of error.
 484   */
 485  function file_save_upload($source, $dest = FALSE, $replace = FILE_EXISTS_RENAME) {
 486    // Make sure $source exists && is valid.
 487    if ($file = file_check_upload($source)) {
 488  
 489      // This should be refactored, file_check_upload has already
 490      // moved the file to the temporary folder.
 491      if (!$dest) {
 492        $dest = file_directory_temp();
 493        $temporary = 1;
 494        if (is_file($file->filepath)) {
 495          // If this file was uploaded by this user before replace the temporary copy.
 496          $replace = FILE_EXISTS_REPLACE;
 497        }
 498      }
 499  
 500      unset($_SESSION['file_uploads'][is_object($source) ? $source->source : $source]);
 501      if (file_move($file, $dest, $replace)) {
 502        if ($temporary) {
 503          $_SESSION['file_uploads'][is_object($source) ? $source->source : $source] = $file;
 504        }
 505        return $file;
 506      }
 507      return 0;
 508    }
 509    return 0;
 510  }
 511  
 512  /**
 513   * Save a string to the specified destination.
 514   *
 515   * @param $data A string containing the contents of the file.
 516   * @param $dest A string containing the destination location.
 517   * @param $replace Replace behavior when the destination file already exists.
 518   *   - FILE_EXISTS_REPLACE - Replace the existing file
 519   *   - FILE_EXISTS_RENAME - Append _{incrementing number} until the filename is unique
 520   *   - FILE_EXISTS_ERROR - Do nothing and return FALSE.
 521   *
 522   * @return A string containing the resulting filename or 0 on error
 523   */
 524  function file_save_data($data, $dest, $replace = FILE_EXISTS_RENAME) {
 525    $temp = file_directory_temp();
 526    $file = tempnam($temp, 'file');
 527    if (!$fp = fopen($file, 'wb')) {
 528      drupal_set_message(t('The file could not be created.'), 'error');
 529      return 0;
 530    }
 531    fwrite($fp, $data);
 532    fclose($fp);
 533  
 534    if (!file_move($file, $dest, $replace)) {
 535      return 0;
 536    }
 537  
 538    return $file;
 539  }
 540  
 541  /**
 542   * Transfer file using http to client. Pipes a file through Drupal to the
 543   * client.
 544   *
 545   * @param $source File to transfer.
 546   * @param $headers An array of http headers to send along with file.
 547   */
 548  function file_transfer($source, $headers) {
 549    ob_end_clean();
 550  
 551    foreach ($headers as $header) {
 552      // To prevent HTTP header injection, we delete new lines that are
 553      // not followed by a space or a tab.
 554      // See http://www.w3.org/Protocols/rfc2616/rfc2616-sec4.html#sec4.2
 555      $header = preg_replace('/\r?\n(?!\t| )/', '', $header);
 556      drupal_set_header($header);
 557    }
 558  
 559    $source = file_create_path($source);
 560  
 561    // Transfer file in 1024 byte chunks to save memory usage.
 562    if ($fd = fopen($source, 'rb')) {
 563      while (!feof($fd)) {
 564        print fread($fd, 1024);
 565      }
 566      fclose($fd);
 567    }
 568    else {
 569      drupal_not_found();
 570    }
 571    exit();
 572  }
 573  
 574  /**
 575   * Call modules that implement hook_file_download() to find out if a file is
 576   * accessible and what headers it should be transferred with. If a module
 577   * returns -1 drupal_access_denied() will be returned. If one or more modules
 578   * returned headers the download will start with the returned headers. If no
 579   * modules respond drupal_not_found() will be returned.
 580   */
 581  
 582  function file_download() {
 583    // Merge remainder of arguments from GET['q'], into relative file path.
 584    $args = func_get_args();
 585    $filepath = implode('/', $args);
 586  
 587    // Maintain compatibility with old ?file=paths saved in node bodies.
 588    if (isset($_GET['file'])) {
 589      $filepath =  $_GET['file'];
 590    }
 591  
 592    if (file_exists(file_create_path($filepath))) {
 593      $headers = module_invoke_all('file_download', $filepath);
 594      if (in_array(-1, $headers)) {
 595          return drupal_access_denied();
 596      }
 597      if (count($headers)) {
 598          file_transfer($filepath, $headers);
 599      }
 600    }
 601    return drupal_not_found();
 602  }
 603  
 604  
 605  /**
 606   * Finds all files that match a given mask in a given directory.
 607   * Directories and files beginning with a period are excluded; this
 608   * prevents hidden files and directories (such as SVN working directories)
 609   * from being scanned.
 610   *
 611   * @param $dir
 612   *   The base directory for the scan.
 613   * @param $mask
 614   *   The regular expression of the files to find.
 615   * @param $nomask
 616   *   An array of files/directories to ignore.
 617   * @param $callback
 618   *   The callback function to call for each match.
 619   * @param $recurse
 620   *   When TRUE, the directory scan will recurse the entire tree
 621   *   starting at the provided directory.
 622   * @param $key
 623   *   The key to be used for the returned array of files. Possible
 624   *   values are "filename", for the path starting with $dir,
 625   *   "basename", for the basename of the file, and "name" for the name
 626   *   of the file without an extension.
 627   * @param $min_depth
 628   *   Minimum depth of directories to return files from.
 629   * @param $depth
 630   *   Current depth of recursion. This parameter is only used internally and should not be passed.
 631   *
 632   * @return
 633   *   An associative array (keyed on the provided key) of objects with
 634   *   "path", "basename", and "name" members corresponding to the
 635   *   matching files.
 636   */
 637  function file_scan_directory($dir, $mask, $nomask = array('.', '..', 'CVS'), $callback = 0, $recurse = TRUE, $key = 'filename', $min_depth = 0, $depth = 0) {
 638    $key = (in_array($key, array('filename', 'basename', 'name')) ? $key : 'filename');
 639    $files = array();
 640  
 641    if (is_dir($dir) && $handle = opendir($dir)) {
 642      while ($file = readdir($handle)) {
 643        if (!in_array($file, $nomask) && $file[0] != '.') {
 644          if (is_dir("$dir/$file") && $recurse) {
 645            $files = array_merge($files, file_scan_directory("$dir/$file", $mask, $nomask, $callback, $recurse, $key, $min_depth, $depth + 1));
 646          }
 647          elseif ($depth >= $min_depth && ereg($mask, $file)) {
 648            $filename = "$dir/$file";
 649            $basename = basename($file);
 650            $name = substr($basename, 0, strrpos($basename, '.'));
 651            $files[$$key] = new stdClass();
 652            $files[$$key]->filename = $filename;
 653            $files[$$key]->basename = $basename;
 654            $files[$$key]->name = $name;
 655            if ($callback) {
 656              $callback($filename);
 657            }
 658          }
 659        }
 660      }
 661  
 662      closedir($handle);
 663    }
 664  
 665    return $files;
 666  }
 667  
 668  /**
 669   * Determine the default temporary directory.
 670   *
 671   * @return A string containing a temp directory.
 672   */
 673  function file_directory_temp() {
 674    $temporary_directory = variable_get('file_directory_temp', NULL);
 675  
 676    if (is_null($temporary_directory)) {
 677      $directories = array();
 678  
 679      // Has PHP been set with an upload_tmp_dir?
 680      if (ini_get('upload_tmp_dir')) {
 681        $directories[] = ini_get('upload_tmp_dir');
 682      }
 683  
 684      // Operating system specific dirs.
 685      if (substr(PHP_OS, 0, 3) == 'WIN') {
 686        $directories[] = 'c:\\windows\\temp';
 687        $directories[] = 'c:\\winnt\\temp';
 688        $path_delimiter = '\\';
 689      }
 690      else {
 691        $directories[] = '/tmp';
 692        $path_delimiter = '/';
 693      }
 694  
 695      foreach ($directories as $directory) {
 696        if (!$temporary_directory && is_dir($directory)) {
 697          $temporary_directory = $directory;
 698        }
 699      }
 700  
 701      // if a directory has been found, use it, otherwise default to 'files/tmp' or 'files\\tmp';
 702      $temporary_directory = $temporary_directory ? $temporary_directory : file_directory_path() . $path_delimiter . 'tmp';
 703      variable_set('file_directory_temp', $temporary_directory);
 704    }
 705  
 706    return $temporary_directory;
 707  }
 708  
 709  /**
 710   * Determine the default 'files' directory.
 711   *
 712   * @return A string containing the path to Drupal's 'files' directory.
 713   */
 714  function file_directory_path() {
 715    return variable_get('file_directory_path', 'files');
 716  }
 717  
 718  /**
 719   * Determine the maximum file upload size by querying the PHP settings.
 720   *
 721   * @return
 722   *   A file size limit in MB based on the PHP upload_max_filesize and post_max_size
 723   */
 724  function file_upload_max_size() {
 725    static $max_size = -1;
 726  
 727    if ($max_size < 0) {
 728      $upload_max = parse_size(ini_get('upload_max_filesize'));
 729      // sanity check- a single upload should not be more than 50% the size limit of the total post
 730      $post_max = parse_size(ini_get('post_max_size')) / 2;
 731      $max_size = ($upload_max < $post_max) ? $upload_max : $post_max;
 732    }
 733    return $max_size;
 734  }