1. 8.5.x core/includes/file.inc
  2. 8.0.x core/includes/file.inc
  3. 8.1.x core/includes/file.inc
  4. 8.2.x core/includes/file.inc
  5. 8.3.x core/includes/file.inc
  6. 8.4.x core/includes/file.inc
  7. 8.6.x core/includes/file.inc
  8. 4.6.x includes/file.inc
  9. 4.7.x includes/file.inc
  10. 5.x includes/file.inc
  11. 6.x includes/file.inc
  12. 7.x includes/file.inc

API for handling file uploads and server file management.

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includes/file.inc
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<?php

/**
 * @file
 * API for handling file uploads and server file management.
 */

/**
 * @defgroup file File interface
 * @{
 * Common file handling functions.
 */
define('FILE_DOWNLOADS_PUBLIC', 1);
define('FILE_DOWNLOADS_PRIVATE', 2);
define('FILE_CREATE_DIRECTORY', 1);
define('FILE_MODIFY_PERMISSIONS', 2);
define('FILE_EXISTS_RENAME', 0);
define('FILE_EXISTS_REPLACE', 1);
define('FILE_EXISTS_ERROR', 2);

/**
 * A files status can be one of two values: temporary or permanent. The status
 * for each file Drupal manages is stored in the {files} tables. If the status
 * is temporary Drupal's file garbage collection will delete the file and
 * remove it from the files table after a set period of time.
 *
 * If you wish to add custom statuses for use by contrib modules please expand as
 * binary flags and consider the first 8 bits reserved. (0,1,2,4,8,16,32,64,128)
 */
define('FILE_STATUS_TEMPORARY', 0);
define('FILE_STATUS_PERMANENT', 1);

/**
 * Create the download path to a file.
 *
 * @param $path A string containing the path of the file to generate URL for.
 * @return A string containing a URL that can be used to download the file.
 */
function file_create_url($path) {

  // Strip file_directory_path from $path. We only include relative paths in URLs.
  if (strpos($path, file_directory_path() . '/') === 0) {
    $path = trim(substr($path, strlen(file_directory_path())), '\\/');
  }
  switch (variable_get('file_downloads', FILE_DOWNLOADS_PUBLIC)) {
    case FILE_DOWNLOADS_PUBLIC:
      return $GLOBALS['base_url'] . '/' . file_directory_path() . '/' . str_replace('\\', '/', $path);
    case FILE_DOWNLOADS_PRIVATE:
      return url('system/files/' . $path, array(
        'absolute' => TRUE,
      ));
  }
}

/**
 * Make sure the destination is a complete path and resides in the file system
 * directory, if it is not prepend the file system directory.
 *
 * @param $dest A string containing the path to verify. If this value is
 *   omitted, Drupal's 'files' directory will be used.
 * @return A string containing the path to file, with file system directory
 *   appended if necessary, or FALSE if the path is invalid (i.e. outside the
 *   configured 'files' or temp directories).
 */
function file_create_path($dest = 0) {
  $file_path = file_directory_path();
  if (!$dest) {
    return $file_path;
  }

  // file_check_location() checks whether the destination is inside the Drupal files directory.
  if (file_check_location($dest, $file_path)) {
    return $dest;
  }
  else {
    if (file_check_location($dest, file_directory_temp())) {
      return $dest;
    }
    else {
      if (file_check_location($file_path . '/' . $dest, $file_path)) {
        return $file_path . '/' . $dest;
      }
    }
  }

  // File not found.
  return FALSE;
}

/**
 * Checks whether a directory exists and is writable.
 *
 * Furthermore, the directory can optionally be created if it does not exist,
 * and/or be set to writable if it is currently not. Directories need to have
 * execute permission to be considered a directory by FTP servers.
 *
 * @param $directory
 *   A string representing the directory path.
 * @param $mode
 *   An optional bitmask containing the actions, if any, to be carried out on
 *   the directory. Any combination of the actions FILE_CREATE_DIRECTORY and
 *   FILE_MODIFY_PERMISSIONS is allowed.
 * @param $form_item
 *   An optional string containing the name of a form item that any errors
 *   will be attached to. Useful when the function validates a directory path
 *   entered as a form value. An error will consequently prevent form submit
 *   handlers from running, and instead display the form along with the
 *   error messages.
 *
 * @return
 *   FALSE if the directory does not exist or is not writable, even after
 *   any optional actions have been carried out. Otherwise, TRUE is returned.
 */
function file_check_directory(&$directory, $mode = 0, $form_item = NULL) {
  $directory = rtrim($directory, '/\\');

  // Check if directory exists.
  if (!is_dir($directory)) {
    if ($mode & FILE_CREATE_DIRECTORY && @mkdir($directory)) {
      drupal_set_message(t('The directory %directory has been created.', array(
        '%directory' => $directory,
      )));
      @chmod($directory, 0775);

      // Necessary for non-webserver users.
    }
    else {
      if ($form_item) {
        form_set_error($form_item, t('The directory %directory does not exist.', array(
          '%directory' => $directory,
        )));
      }
      return FALSE;
    }
  }

  // Check to see if the directory is writable.
  if (!is_writable($directory)) {
    if ($mode & FILE_MODIFY_PERMISSIONS && @chmod($directory, 0775)) {
      drupal_set_message(t('The permissions of directory %directory have been changed to make it writable.', array(
        '%directory' => $directory,
      )));
    }
    else {
      form_set_error($form_item, t('The directory %directory is not writable', array(
        '%directory' => $directory,
      )));
      watchdog('file system', 'The directory %directory is not writable, because it does not have the correct permissions set.', array(
        '%directory' => $directory,
      ), WATCHDOG_ERROR);
      return FALSE;
    }
  }
  if (file_directory_path() == $directory || file_directory_temp() == $directory) {
    file_create_htaccess($directory, $form_item);
  }
  return TRUE;
}

/**
 * Creates a .htaccess file in the given directory.
 *
 * @param $directory
 *   The directory.
 * @param $form_item
 *   An optional string containing the name of a form item that any errors
 *   will be attached to. Useful when called from file_check_directory() to
 *   validate a directory path entered as a form value. An error will
 *   consequently prevent form submit handlers from running, and instead
 *   display the form along with the error messages.
 * @param $force_overwrite
 *   Set to TRUE to attempt to overwrite the existing .htaccess file if one is
 *   already present. Defaults to FALSE.
 */
function file_create_htaccess($directory, $form_item = NULL, $force_overwrite = FALSE) {
  if (!is_file("{$directory}/.htaccess") || $force_overwrite) {
    $htaccess_lines = file_htaccess_lines();
    if (($fp = fopen("{$directory}/.htaccess", 'w')) && fputs($fp, $htaccess_lines)) {
      fclose($fp);
      chmod($directory . '/.htaccess', 0664);
    }
    else {
      $variables = array(
        '%directory' => $directory,
        '!htaccess' => '<br />' . nl2br(check_plain($htaccess_lines)),
      );
      if ($form_item) {
        form_set_error($form_item, 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>", $variables));
      }
      watchdog('security', "Security warning: Couldn't write .htaccess file. Please create a .htaccess file in your %directory directory which contains the following lines: <code>!htaccess</code>", $variables, WATCHDOG_ERROR);
    }
  }
}

/**
 * Returns the standard .htaccess lines that Drupal writes to file directories.
 *
 * @return
 *   A string representing the desired contents of the .htaccess file.
 *
 * @see file_create_htaccess()
 */
function file_htaccess_lines() {
  $lines = <<<EOF
# Turn off all options we don't need.
Options None
Options +FollowSymLinks

# Set the catch-all handler to prevent scripts from being executed.
SetHandler Drupal_Security_Do_Not_Remove_See_SA_2006_006
<Files *>
  # Override the handler again if we're run later in the evaluation list.
  SetHandler Drupal_Security_Do_Not_Remove_See_SA_2013_003
</Files>

# If we know how to do it safely, disable the PHP engine entirely.
<IfModule mod_php5.c>
  php_flag engine off
</IfModule>
# PHP 4, Apache 1.
<IfModule mod_php4.c>
  php_flag engine off
</IfModule>
# PHP 4, Apache 2.
<IfModule sapi_apache2.c>
  php_flag engine off
</IfModule>
EOF;
  return $lines;
}

/**
 * Checks path to see if it is a directory, or a dir/file.
 *
 * @param $path A string containing a file path. This will be set to the
 *   directory's path.
 * @return If the directory is not in a Drupal writable directory, FALSE is
 *   returned. Otherwise, the base name of the path is returned.
 */
function file_check_path(&$path) {

  // Check if path is a directory.
  if (file_check_directory($path)) {
    return '';
  }

  // Check if path is a possible dir/file.
  $filename = basename($path);
  $path = dirname($path);
  if (file_check_directory($path)) {
    return $filename;
  }
  return FALSE;
}

/**
 * Check if a file is really located inside $directory. Should be used to make
 * sure a file specified is really located within the directory to prevent
 * exploits.
 *
 * @code
 *   // Returns FALSE:
 *   file_check_location('/www/example.com/files/../../../etc/passwd', '/www/example.com/files');
 * @endcode
 *
 * @param $source A string set to the file to check.
 * @param $directory A string where the file should be located.
 * @return 0 for invalid path or the real path of the source.
 */
function file_check_location($source, $directory = '') {
  $check = realpath($source);
  if ($check) {
    $source = $check;
  }
  else {

    // This file does not yet exist
    $source = realpath(dirname($source)) . '/' . basename($source);
  }
  $directory = realpath($directory);
  if ($directory && strpos($source, $directory) !== 0) {
    return 0;
  }
  return $source;
}

/**
 * Copies a file to a new location.
 *
 * This is a powerful function that in many ways performs like an advanced
 * version of copy().
 * - Checks if $source and $dest are valid and readable/writable.
 * - Performs a file copy if $source is not equal to $dest.
 * - If file already exists in $dest either the call will error out, replace the
 *   file or rename the file based on the $replace parameter.
 *
 * @param $source
 *   Either a string specifying the file location of the original file or an
 *   object containing a 'filepath' property. This parameter is passed by
 *   reference and will contain the resulting destination filename in case of
 *   success.
 * @param $dest
 *   A string containing the directory $source should be copied to. If this
 *   value is omitted, Drupal's 'files' directory will be used.
 * @param $replace
 *   Replace behavior when the destination file already exists.
 *   - FILE_EXISTS_REPLACE: Replace the existing file.
 *   - FILE_EXISTS_RENAME: Append _{incrementing number} until the filename is
 *     unique.
 *   - FILE_EXISTS_ERROR: Do nothing and return FALSE.
 * @return
 *   TRUE for success, FALSE for failure.
 */
function file_copy(&$source, $dest = 0, $replace = FILE_EXISTS_RENAME) {
  $dest = file_create_path($dest);
  $directory = $dest;
  $basename = file_check_path($directory);

  // Make sure we at least have a valid directory.
  if ($basename === FALSE) {
    $source = is_object($source) ? $source->filepath : $source;
    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');
    watchdog('file system', '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);
    return 0;
  }

  // Process a file upload object.
  if (is_object($source)) {
    $file = $source;
    $source = $file->filepath;
    if (!$basename) {
      $basename = $file->filename;
    }
  }
  $source = realpath($source);
  if (!file_exists($source)) {
    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');
    return 0;
  }

  // If the destination file is not specified then use the filename of the source file.
  $basename = $basename ? $basename : basename($source);
  $dest = $directory . '/' . $basename;

  // Make sure source and destination filenames are not the same, makes no sense
  // to copy it if they are. In fact copying the file will most likely result in
  // a 0 byte file. Which is bad. Real bad.
  if ($source != realpath($dest)) {
    if (!($dest = file_destination($dest, $replace))) {
      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' => $source,
      )), 'error');
      return FALSE;
    }
    if (!@copy($source, $dest)) {
      drupal_set_message(t('The selected file %file could not be copied.', array(
        '%file' => $source,
      )), 'error');
      return 0;
    }

    // Give everyone read access so that FTP'd users or
    // non-webserver users can see/read these files,
    // and give group write permissions so group members
    // can alter files uploaded by the webserver.
    @chmod($dest, 0664);
  }
  if (isset($file) && is_object($file)) {
    $file->filename = $basename;
    $file->filepath = $dest;
    $source = $file;
  }
  else {
    $source = $dest;
  }
  return 1;

  // Everything went ok.
}

/**
 * Determines the destination path for a file depending on how replacement of
 * existing files should be handled.
 *
 * @param $destination A string specifying the desired path.
 * @param $replace Replace behavior when the destination file already exists.
 *   - FILE_EXISTS_REPLACE - Replace the existing file
 *   - FILE_EXISTS_RENAME - Append _{incrementing number} until the filename is
 *     unique
 *   - FILE_EXISTS_ERROR - Do nothing and return FALSE.
 * @return The destination file path or FALSE if the file already exists and
 *   FILE_EXISTS_ERROR was specified.
 */
function file_destination($destination, $replace) {
  if (file_exists($destination)) {
    switch ($replace) {
      case FILE_EXISTS_RENAME:
        $basename = basename($destination);
        $directory = dirname($destination);
        $destination = file_create_filename($basename, $directory);
        break;
      case FILE_EXISTS_ERROR:
        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' => $destination,
        )), 'error');
        return FALSE;
    }
  }
  return $destination;
}

/**
 * Moves a file to a new location.
 *
 * - Checks if $source and $dest are valid and readable/writable.
 * - Performs a file move if $source is not equal to $dest.
 * - If file already exists in $dest either the call will error out, replace the
 *   file or rename the file based on the $replace parameter.
 *
 * @param $source
 *   Either a string specifying the file location of the original file or an
 *   object containing a 'filepath' property. This parameter is passed by
 *   reference and will contain the resulting destination filename in case of
 *   success.
 * @param $dest
 *   A string containing the directory $source should be copied to. If this
 *   value is omitted, Drupal's 'files' directory will be used.
 * @param $replace
 *   Replace behavior when the destination file already exists.
 *   - FILE_EXISTS_REPLACE: Replace the existing file.
 *   - FILE_EXISTS_RENAME: Append _{incrementing number} until the filename is
 *     unique.
 *   - FILE_EXISTS_ERROR: Do nothing and return FALSE.
 * @return
 *   TRUE for success, FALSE for failure.
 */
function file_move(&$source, $dest = 0, $replace = FILE_EXISTS_RENAME) {
  $path_original = is_object($source) ? $source->filepath : $source;
  if (file_copy($source, $dest, $replace)) {
    $path_current = is_object($source) ? $source->filepath : $source;
    if ($path_original == $path_current || file_delete($path_original)) {
      return 1;
    }
    drupal_set_message(t('The removal of the original file %file has failed.', array(
      '%file' => $path_original,
    )), 'error');
  }
  return 0;
}

/**
 * Modify a filename as needed for security purposes.
 *
 * Munging a file name prevents unknown file extensions from masking exploit
 * files. When web servers such as Apache decide how to process a URL request,
 * they use the file extension. If the extension is not recognized, Apache
 * skips that extension and uses the previous file extension. For example, if
 * the file being requested is exploit.php.pps, and Apache does not recognize
 * the '.pps' extension, it treats the file as PHP and executes it. To make
 * this file name safe for Apache and prevent it from executing as PHP, the
 * .php extension is "munged" into .php_, making the safe file name
 * exploit.php_.pps.
 *
 * Specifically, this function adds an underscore to all extensions that are
 * between 2 and 5 characters in length, internal to the file name, and not
 * included in $extensions.
 *
 * Function behavior is also controlled by the Drupal variable
 * 'allow_insecure_uploads'. If 'allow_insecure_uploads' evaluates to TRUE, no
 * alterations will be made, if it evaluates to FALSE, the filename is 'munged'.
 *
 * @param $filename
 *   File name to modify.
 * @param $extensions
 *   A space-separated list of extensions that should not be altered.
 * @param $alerts
 *   If TRUE, drupal_set_message() will be called to display a message if the
 *   file name was changed.
 *
 * @return
 *   The potentially modified $filename.
 */
function file_munge_filename($filename, $extensions, $alerts = TRUE) {
  $original = $filename;

  // Allow potentially insecure uploads for very savvy users and admin
  if (!variable_get('allow_insecure_uploads', 0)) {

    // Remove any null bytes. See http://php.net/manual/en/security.filesystem.nullbytes.php
    $filename = str_replace(chr(0), '', $filename);
    $whitelist = array_unique(explode(' ', trim($extensions)));

    // Split the filename up by periods. The first part becomes the basename
    // the last part the final extension.
    $filename_parts = explode('.', $filename);
    $new_filename = array_shift($filename_parts);

    // Remove file basename.
    $final_extension = array_pop($filename_parts);

    // Remove final extension.
    // Loop through the middle parts of the name and add an underscore to the
    // end of each section that could be a file extension but isn't in the list
    // of allowed extensions.
    foreach ($filename_parts as $filename_part) {
      $new_filename .= '.' . $filename_part;
      if (!in_array($filename_part, $whitelist) && preg_match("/^[a-zA-Z]{2,5}\\d?\$/", $filename_part)) {
        $new_filename .= '_';
      }
    }
    $filename = $new_filename . '.' . $final_extension;
    if ($alerts && $original != $filename) {
      drupal_set_message(t('For security reasons, your upload has been renamed to %filename.', array(
        '%filename' => $filename,
      )));
    }
  }
  return $filename;
}

/**
 * Undo the effect of upload_munge_filename().
 *
 * @param $filename string filename
 * @return string
 */
function file_unmunge_filename($filename) {
  return str_replace('_.', '.', $filename);
}

/**
 * Create a full file path from a directory and filename. If a file with the
 * specified name already exists, an alternative will be used.
 *
 * @param $basename string filename
 * @param $directory string directory
 * @return
 */
function file_create_filename($basename, $directory) {
  $dest = $directory . '/' . $basename;
  if (file_exists($dest)) {

    // Destination file already exists, generate an alternative.
    if ($pos = strrpos($basename, '.')) {
      $name = substr($basename, 0, $pos);
      $ext = substr($basename, $pos);
    }
    else {
      $name = $basename;
      $ext = '';
    }
    $counter = 0;
    do {
      $dest = $directory . '/' . $name . '_' . $counter++ . $ext;
    } while (file_exists($dest));
  }
  return $dest;
}

/**
 * Delete a file.
 *
 * @param $path A string containing a file path.
 * @return TRUE for success, FALSE for failure.
 */
function file_delete($path) {
  if (is_file($path)) {
    return unlink($path);
  }
}

/**
 * Determine total disk space used by a single user or the whole filesystem.
 *
 * @param $uid
 *   An optional user id. A NULL value returns the total space used
 *   by all files.
 */
function file_space_used($uid = NULL) {
  if (isset($uid)) {
    return (int) db_result(db_query('SELECT SUM(filesize) FROM {files} WHERE uid = %d', $uid));
  }
  return (int) db_result(db_query('SELECT SUM(filesize) FROM {files}'));
}

/**
 * Saves a file upload to a new location.
 *
 * The source file is validated as a proper upload and handled as such.
 * The file will be added to the files table as a temporary file. Temporary
 * files are periodically cleaned. To make the file permanent file call
 * file_set_status() to change its status.
 *
 * @param $source
 *   A string specifying the name of the upload field to save.
 * @param $validators
 *   (optional) An associative array of callback functions used to validate the
 *   file. The keys are function names and the values arrays of callback
 *   parameters which will be passed in after the file object. The
 *   functions should return an array of error messages; an empty array
 *   indicates that the file passed validation. The functions will be called in
 *   the order specified.
 * @param $dest
 *   A string containing the directory $source should be copied to. If this is
 *   not provided or is not writable, the temporary directory will be used.
 * @param $replace
 *   Replace behavior when the destination file already exists:
 *   - FILE_EXISTS_REPLACE: Replace the existing file.
 *   - FILE_EXISTS_RENAME: Append _{incrementing number} until the filename
 *     is unique.
 *   - FILE_EXISTS_ERROR: Do nothing and return FALSE.
 *
 * @return
 *   An object containing the file information, or 0 in the event of an error.
 */
function file_save_upload($source, $validators = array(), $dest = FALSE, $replace = FILE_EXISTS_RENAME) {
  global $user;
  static $upload_cache;

  // Add our check of the file name length.
  $validators['file_validate_name_length'] = array();

  // Return cached objects without processing since the file will have
  // already been processed and the paths in _FILES will be invalid.
  if (isset($upload_cache[$source])) {
    return $upload_cache[$source];
  }

  // If a file was uploaded, process it.
  if (isset($_FILES['files']) && $_FILES['files']['name'][$source] && is_uploaded_file($_FILES['files']['tmp_name'][$source])) {

    // Check for file upload errors and return FALSE if a
    // lower level system error occurred.
    switch ($_FILES['files']['error'][$source]) {

      // @see http://php.net/manual/en/features.file-upload.errors.php
      case UPLOAD_ERR_OK:
        break;
      case UPLOAD_ERR_INI_SIZE:
      case UPLOAD_ERR_FORM_SIZE:
        drupal_set_message(t('The file %file could not be saved, because it exceeds %maxsize, the maximum allowed size for uploads.', array(
          '%file' => $source,
          '%maxsize' => format_size(file_upload_max_size()),
        )), 'error');
        return 0;
      case UPLOAD_ERR_PARTIAL:
      case UPLOAD_ERR_NO_FILE:
        drupal_set_message(t('The file %file could not be saved, because the upload did not complete.', array(
          '%file' => $source,
        )), 'error');
        return 0;

        // Unknown error

      // Unknown error
      default:
        drupal_set_message(t('The file %file could not be saved. An unknown error has occurred.', array(
          '%file' => $source,
        )), 'error');
        return 0;
    }

    // Build the list of non-munged extensions.
    // @todo: this should not be here. we need to figure out the right place.
    $extensions = '';
    foreach ($user->roles as $rid => $name) {
      $extensions .= ' ' . variable_get("upload_extensions_{$rid}", variable_get('upload_extensions_default', 'jpg jpeg gif png txt html doc xls pdf ppt pps odt ods odp'));
    }

    // Begin building file object.
    $file = new stdClass();
    $file->filename = file_munge_filename(trim(basename($_FILES['files']['name'][$source]), '.'), $extensions);
    $file->filepath = $_FILES['files']['tmp_name'][$source];
    $file->filemime = file_get_mimetype($file->filename);

    // If the destination is not provided, or is not writable, then use the
    // temporary directory.
    if (empty($dest) || file_check_path($dest) === FALSE) {
      $dest = file_directory_temp();
    }
    $file->source = $source;
    $file->destination = file_destination(file_create_path($dest . '/' . $file->filename), $replace);
    $file->filesize = $_FILES['files']['size'][$source];

    // Call the validation functions.
    $errors = array();
    foreach ($validators as $function => $args) {
      array_unshift($args, $file);

      // Make sure $file is passed around by reference.
      $args[0] =& $file;
      $errors = array_merge($errors, call_user_func_array($function, $args));
    }

    // Rename potentially executable files, to help prevent exploits.
    if (preg_match('/\\.(php|pl|py|cgi|asp|js)$/i', $file->filename) && substr($file->filename, -4) != '.txt') {
      $file->filemime = 'text/plain';
      $file->filepath .= '.txt';
      $file->filename .= '.txt';

      // As the file may be named example.php.txt, we need to munge again to
      // convert to example.php_.txt, then create the correct destination.
      $file->filename = file_munge_filename($file->filename, $extensions);
      $file->destination = file_destination(file_create_path($dest . '/' . $file->filename), $replace);
    }

    // Check for validation errors.
    if (!empty($errors)) {
      $message = t('The selected file %name could not be uploaded.', array(
        '%name' => $file->filename,
      ));
      if (count($errors) > 1) {
        $message .= '<ul><li>' . implode('</li><li>', $errors) . '</li></ul>';
      }
      else {
        $message .= ' ' . array_pop($errors);
      }
      form_set_error($source, $message);
      return 0;
    }

    // Move uploaded files from PHP's upload_tmp_dir to Drupal's temporary directory.
    // This overcomes open_basedir restrictions for future file operations.
    $file->filepath = $file->destination;
    if (!move_uploaded_file($_FILES['files']['tmp_name'][$source], $file->filepath)) {
      form_set_error($source, t('File upload error. Could not move uploaded file.'));
      watchdog('file', 'Upload error. Could not move uploaded file %file to destination %destination.', array(
        '%file' => $file->filename,
        '%destination' => $file->filepath,
      ));
      return 0;
    }

    // If we made it this far it's safe to record this file in the database.
    $file->uid = $user->uid;
    $file->status = FILE_STATUS_TEMPORARY;
    $file->timestamp = time();
    drupal_write_record('files', $file);

    // Add file to the cache.
    $upload_cache[$source] = $file;
    return $file;
  }
  return 0;
}

/**
 * Check for files with names longer than we can store in the database.
 *
 * @param $file
 *   A Drupal file object.
 * @return
 *   An array. If the file name is too long, it will contain an error message.
 */
function file_validate_name_length($file) {
  $errors = array();
  if (strlen($file->filename) > 255) {
    $errors[] = t('Its name exceeds the 255 characters limit. Please rename the file and try again.');
  }
  return $errors;
}

/**
 * Check that the filename ends with an allowed extension. This check is not
 * enforced for the user #1.
 *
 * @param $file
 *   A Drupal file object.
 * @param $extensions
 *   A string with a space separated list of allowed file extensions, not
 *   including the period. For example, 'bmp jpg gif png'.
 *
 * @return
 *   An array. If the file extension is not allowed, it will contain an error
 *   message.
 */
function file_validate_extensions($file, $extensions) {
  global $user;
  $errors = array();

  // Bypass validation for uid  = 1.
  if ($user->uid != 1) {
    $regex = '/\\.(' . @ereg_replace(' +', '|', preg_quote($extensions)) . ')$/i';
    if (!preg_match($regex, $file->filename)) {
      $errors[] = t('Only files with the following extensions are allowed: %files-allowed.', array(
        '%files-allowed' => $extensions,
      ));
    }
  }
  return $errors;
}

/**
 * Check that the file's size is below certain limits. This check is not
 * enforced for the user #1.
 *
 * @param $file
 *   A Drupal file object.
 * @param $file_limit
 *   An integer specifying the maximum file size in bytes. Zero indicates that
 *   no limit should be enforced.
 * @param $user_limit
 *   An integer specifying the maximum number of bytes the user is allowed. Zero
 *   indicates that no limit should be enforced.
 * @return
 *   An array. If the file size exceeds limits, it will contain an error message.
 */
function file_validate_size($file, $file_limit = 0, $user_limit = 0) {
  global $user;
  $errors = array();

  // Bypass validation for uid  = 1.
  if ($user->uid != 1) {
    if ($file_limit && $file->filesize > $file_limit) {
      $errors[] = t('The file is %filesize exceeding the maximum file size of %maxsize.', array(
        '%filesize' => format_size($file->filesize),
        '%maxsize' => format_size($file_limit),
      ));
    }

    // Save a query by only calling file_space_used() when a limit is provided.
    if ($user_limit && file_space_used($user->uid) + $file->filesize > $user_limit) {
      $errors[] = t('The file is %filesize which would exceed your disk quota of %quota.', array(
        '%filesize' => format_size($file->filesize),
        '%quota' => format_size($user_limit),
      ));
    }
  }
  return $errors;
}

/**
 * Check that the file is recognized by image_get_info() as an image.
 *
 * @param $file
 *   A Drupal file object.
 * @return
 *   An array. If the file is not an image, it will contain an error message.
 */
function file_validate_is_image(&$file) {
  $errors = array();
  $info = image_get_info($file->filepath);
  if (!$info || empty($info['extension'])) {
    $errors[] = t('Only JPEG, PNG and GIF images are allowed.');
  }
  return $errors;
}

/**
 * If the file is an image verify that its dimensions are within the specified
 * maximum and minimum dimensions. Non-image files will be ignored.
 *
 * @param $file
 *   A Drupal file object. This function may resize the file affecting its size.
 * @param $maximum_dimensions
 *   An optional string in the form WIDTHxHEIGHT e.g. '640x480' or '85x85'. If
 *   an image toolkit is installed the image will be resized down to these
 *   dimensions. A value of 0 indicates no restriction on size, so resizing
 *   will be attempted.
 * @param $minimum_dimensions
 *   An optional string in the form WIDTHxHEIGHT. This will check that the image
 *   meets a minimum size. A value of 0 indicates no restriction.
 * @return
 *   An array. If the file is an image and did not meet the requirements, it
 *   will contain an error message.
 */
function file_validate_image_resolution(&$file, $maximum_dimensions = 0, $minimum_dimensions = 0) {
  $errors = array();

  // Check first that the file is an image.
  if ($info = image_get_info($file->filepath)) {
    if ($maximum_dimensions) {

      // Check that it is smaller than the given dimensions.
      list($width, $height) = explode('x', $maximum_dimensions);
      if ($info['width'] > $width || $info['height'] > $height) {

        // Try to resize the image to fit the dimensions.
        if (image_get_toolkit() && image_scale($file->filepath, $file->filepath, $width, $height)) {
          drupal_set_message(t('The image was resized to fit within the maximum allowed dimensions of %dimensions pixels.', array(
            '%dimensions' => $maximum_dimensions,
          )));

          // Clear the cached filesize and refresh the image information.
          clearstatcache();
          $info = image_get_info($file->filepath);
          $file->filesize = $info['file_size'];
        }
        else {
          $errors[] = t('The image is too large; the maximum dimensions are %dimensions pixels.', array(
            '%dimensions' => $maximum_dimensions,
          ));
        }
      }
    }
    if ($minimum_dimensions) {

      // Check that it is larger than the given dimensions.
      list($width, $height) = explode('x', $minimum_dimensions);
      if ($info['width'] < $width || $info['height'] < $height) {
        $errors[] = t('The image is too small; the minimum dimensions are %dimensions pixels.', array(
          '%dimensions' => $minimum_dimensions,
        ));
      }
    }
  }
  return $errors;
}

/**
 * Save a string to the specified destination.
 *
 * @param $data A string containing the contents of the file.
 * @param $dest A string containing the destination location.
 * @param $replace Replace behavior when the destination file already exists.
 *   - FILE_EXISTS_REPLACE - Replace the existing file
 *   - FILE_EXISTS_RENAME - Append _{incrementing number} until the filename is unique
 *   - FILE_EXISTS_ERROR - Do nothing and return FALSE.
 *
 * @return A string containing the resulting filename or 0 on error
 */
function file_save_data($data, $dest, $replace = FILE_EXISTS_RENAME) {
  $temp = file_directory_temp();

  // On Windows, tempnam() requires an absolute path, so we use realpath().
  $file = tempnam(realpath($temp), 'file');
  if (!($fp = fopen($file, 'wb'))) {
    drupal_set_message(t('The file could not be created.'), 'error');
    return 0;
  }
  fwrite($fp, $data);
  fclose($fp);
  if (!file_move($file, $dest, $replace)) {
    return 0;
  }
  return $file;
}

/**
 * Set the status of a file.
 *
 * @param $file 
 *   A Drupal file object.
 * @param $status
 *   A status value to set the file to. One of:
 *   - FILE_STATUS_PERMANENT
 *   - FILE_STATUS_TEMPORARY
 *
 * @return FALSE on failure, TRUE on success and $file->status will contain the
 *     status.
 */
function file_set_status(&$file, $status) {
  if (db_query('UPDATE {files} SET status = %d WHERE fid = %d', $status, $file->fid)) {
    $file->status = $status;
    return TRUE;
  }
  return FALSE;
}

/**
 * Transfer file using http to client. Pipes a file through Drupal to the
 * client.
 *
 * @param $source File to transfer.
 * @param $headers An array of http headers to send along with file.
 */
function file_transfer($source, $headers) {
  if (ob_get_level()) {
    ob_end_clean();
  }

  // IE cannot download private files because it cannot store files downloaded
  // over HTTPS in the browser cache. The problem can be solved by sending
  // custom headers to IE. See http://support.microsoft.com/kb/323308/en-us
  if (isset($_SERVER['HTTPS']) && $_SERVER['HTTPS'] == 'on') {
    drupal_set_header('Cache-Control: private');
    drupal_set_header('Pragma: private');
  }
  foreach ($headers as $header) {

    // To prevent HTTP header injection, we delete new lines that are
    // not followed by a space or a tab.
    // See http://www.w3.org/Protocols/rfc2616/rfc2616-sec4.html#sec4.2
    $header = preg_replace('/\\r?\\n(?!\\t| )/', '', $header);
    drupal_set_header($header);
  }
  $source = file_create_path($source);

  // Transfer file in 1024 byte chunks to save memory usage.
  if ($fd = fopen($source, 'rb')) {
    while (!feof($fd)) {
      print fread($fd, 1024);
    }
    fclose($fd);
  }
  else {
    drupal_not_found();
  }
  exit;
}

/**
 * Call modules that implement hook_file_download() to find out if a file is
 * accessible and what headers it should be transferred with. If a module
 * returns -1 drupal_access_denied() will be returned. If one or more modules
 * returned headers the download will start with the returned headers. If no
 * modules respond drupal_not_found() will be returned.
 */
function file_download() {

  // Merge remainder of arguments from GET['q'], into relative file path.
  $args = func_get_args();
  $filepath = implode('/', $args);

  // Maintain compatibility with old ?file=paths saved in node bodies.
  if (isset($_GET['file'])) {
    $filepath = $_GET['file'];
  }
  if (file_exists(file_create_path($filepath))) {
    $headers = file_download_headers($filepath);
    if (count($headers)) {
      file_transfer($filepath, $headers);
    }
    else {
      return drupal_access_denied();
    }
  }
  return drupal_not_found();
}

/**
 * Retrieves headers for a private file download.
 *
 * Calls all module implementations of hook_file_download() to retrieve headers
 * for files by the module that originally provided the file. The presence of
 * returned headers indicates the current user has access to the file.
 *
 * @param $filepath
 *   The path for the file whose headers should be retrieved.
 *
 * @return
 *   If access is allowed, headers for the file, suitable for passing to
 *   file_transfer(). If access is not allowed, an empty array will be returned.
 *
 * @see file_transfer()
 * @see file_download_access()
 * @see hook_file_downlaod()
 */
function file_download_headers($filepath) {
  $headers = module_invoke_all('file_download', $filepath);
  if (in_array(-1, $headers)) {

    // Throw away the headers received so far.
    $headers = array();
  }
  return $headers;
}

/**
 * Checks that the current user has access to a particular file.
 *
 * The return value of this function hinges on the return value from
 * file_download_headers(), which is the function responsible for collecting
 * access information through hook_file_download().
 *
 * If immediately transferring the file to the browser and the headers will
 * need to be retrieved, the return value of file_download_headers() should be
 * used to determine access directly, so that access checks will not be run
 * twice.
 *
 * @param $filepath
 *   The path for the file whose headers should be retrieved.
 *
 * @return
 *   Boolean TRUE if access is allowed. FALSE if access is not allowed.
 *
 * @see file_download_headers()
 * @see hook_file_download()
 */
function file_download_access($filepath) {
  return count(file_download_headers($filepath)) > 0;
}

/**
 * Finds all files that match a given mask in a given directory.
 *
 * Directories and files beginning with a period are excluded; this
 * prevents hidden files and directories (such as SVN working directories)
 * from being scanned.
 *
 * @param $dir
 *   The base directory for the scan, without trailing slash.
 * @param $mask
 *   The regular expression of the files to find.
 * @param $nomask
 *   An array of files/directories to ignore.
 * @param $callback
 *   The callback function to call for each match.
 * @param $recurse
 *   When TRUE, the directory scan will recurse the entire tree
 *   starting at the provided directory.
 * @param $key
 *   The key to be used for the returned associative array of files. Possible
 *   values are "filename", for the path starting with $dir; "basename", for
 *   the basename of the file; and "name" for the name of the file without the
 *   extension.
 * @param $min_depth
 *   Minimum depth of directories to return files from.
 * @param $depth
 *   Current depth of recursion. This parameter is only used internally and
 *   should not be passed in.
 *
 * @return
 *   An associative array (keyed on the provided key) of objects with
 *   "filename", "basename", and "name" members corresponding to the
 *   matching files.
 */
function file_scan_directory($dir, $mask, $nomask = array(
  '.',
  '..',
  'CVS',
), $callback = 0, $recurse = TRUE, $key = 'filename', $min_depth = 0, $depth = 0) {
  $key = in_array($key, array(
    'filename',
    'basename',
    'name',
  )) ? $key : 'filename';
  $files = array();
  if (is_dir($dir) && ($handle = opendir($dir))) {
    while (FALSE !== ($file = readdir($handle))) {
      if (!in_array($file, $nomask) && $file[0] != '.') {
        if (is_dir("{$dir}/{$file}") && $recurse) {

          // Give priority to files in this folder by merging them in after any subdirectory files.
          $files = array_merge(file_scan_directory("{$dir}/{$file}", $mask, $nomask, $callback, $recurse, $key, $min_depth, $depth + 1), $files);
        }
        elseif ($depth >= $min_depth && @ereg($mask, $file)) {

          // Always use this match over anything already set in $files with the same $$key.
          $filename = "{$dir}/{$file}";
          $basename = basename($file);
          $name = substr($basename, 0, strrpos($basename, '.'));
          $files[${$key}] = new stdClass();
          $files[${$key}]->filename = $filename;
          $files[${$key}]->basename = $basename;
          $files[${$key}]->name = $name;
          if ($callback) {
            $callback($filename);
          }
        }
      }
    }
    closedir($handle);
  }
  return $files;
}

/**
 * Determine the default temporary directory.
 *
 * @return A string containing a temp directory.
 */
function file_directory_temp() {
  $temporary_directory = variable_get('file_directory_temp', NULL);
  if (is_null($temporary_directory)) {
    $directories = array();

    // Has PHP been set with an upload_tmp_dir?
    if (ini_get('upload_tmp_dir')) {
      $directories[] = ini_get('upload_tmp_dir');
    }

    // Operating system specific dirs.
    if (substr(PHP_OS, 0, 3) == 'WIN') {
      $directories[] = 'c:\\windows\\temp';
      $directories[] = 'c:\\winnt\\temp';
      $path_delimiter = '\\';
    }
    else {
      $directories[] = '/tmp';
      $path_delimiter = '/';
    }
    foreach ($directories as $directory) {
      if (!$temporary_directory && is_dir($directory)) {
        $temporary_directory = $directory;
      }
    }

    // if a directory has been found, use it, otherwise default to 'files/tmp' or 'files\\tmp';
    $temporary_directory = $temporary_directory ? $temporary_directory : file_directory_path() . $path_delimiter . 'tmp';
    variable_set('file_directory_temp', $temporary_directory);
  }
  return $temporary_directory;
}

/**
 * Determine the default 'files' directory.
 *
 * @return A string containing the path to Drupal's 'files' directory.
 */
function file_directory_path() {
  return variable_get('file_directory_path', conf_path() . '/files');
}

/**
 * Determine the maximum file upload size by querying the PHP settings.
 *
 * @return
 *   A file size limit in bytes based on the PHP upload_max_filesize and post_max_size
 */
function file_upload_max_size() {
  static $max_size = -1;
  if ($max_size < 0) {
    $upload_max = parse_size(ini_get('upload_max_filesize'));
    $post_max = parse_size(ini_get('post_max_size'));
    $max_size = $upload_max < $post_max ? $upload_max : $post_max;
  }
  return $max_size;
}

/**
 * Determine an Internet Media Type, or MIME type from a filename.
 *
 * @param $filename
 *   Name of the file, including extension.
 * @param $mapping
 *   An optional array of extension to media type mappings in the form
 *   'extension1|extension2|...' => 'type'.
 *
 * @return
 *   The internet media type registered for the extension or application/octet-stream for unknown extensions.
 */
function file_get_mimetype($filename, $mapping = NULL) {
  if (!is_array($mapping)) {
    $mapping = variable_get('mime_extension_mapping', array(
      'ez' => 'application/andrew-inset',
      'atom' => 'application/atom',
      'atomcat' => 'application/atomcat+xml',
      'atomsrv' => 'application/atomserv+xml',
      'cap|pcap' => 'application/cap',
      'cu' => 'application/cu-seeme',
      'tsp' => 'application/dsptype',
      'spl' => 'application/x-futuresplash',
      'hta' => 'application/hta',
      'jar' => 'application/java-archive',
      'ser' => 'application/java-serialized-object',
      'class' => 'application/java-vm',
      'hqx' => 'application/mac-binhex40',
      'cpt' => 'image/x-corelphotopaint',
      'nb' => 'application/mathematica',
      'mdb' => 'application/msaccess',
      'doc|dot' => 'application/msword',
      'bin' => 'application/octet-stream',
      'oda' => 'application/oda',
      'ogg|ogx' => 'application/ogg',
      'pdf' => 'application/pdf',
      'key' => 'application/pgp-keys',
      'pgp' => 'application/pgp-signature',
      'prf' => 'application/pics-rules',
      'ps|ai|eps' => 'application/postscript',
      'rar' => 'application/rar',
      'rdf' => 'application/rdf+xml',
      'rss' => 'application/rss+xml',
      'rtf' => 'application/rtf',
      'smi|smil' => 'application/smil',
      'wpd' => 'application/wordperfect',
      'wp5' => 'application/wordperfect5.1',
      'xhtml|xht' => 'application/xhtml+xml',
      'xml|xsl' => 'application/xml',
      'zip' => 'application/zip',
      'cdy' => 'application/vnd.cinderella',
      'kml' => 'application/vnd.google-earth.kml+xml',
      'kmz' => 'application/vnd.google-earth.kmz',
      'xul' => 'application/vnd.mozilla.xul+xml',
      'xls|xlb|xlt' => 'application/vnd.ms-excel',
      'cat' => 'application/vnd.ms-pki.seccat',
      'stl' => 'application/vnd.ms-pki.stl',
      'ppt|pps' => 'application/vnd.ms-powerpoint',
      'odc' => 'application/vnd.oasis.opendocument.chart',
      'odb' => 'application/vnd.oasis.opendocument.database',
      'odf' => 'application/vnd.oasis.opendocument.formula',
      'odg' => 'application/vnd.oasis.opendocument.graphics',
      'otg' => 'application/vnd.oasis.opendocument.graphics-template',
      'odi' => 'application/vnd.oasis.opendocument.image',
      'odp' => 'application/vnd.oasis.opendocument.presentation',
      'otp' => 'application/vnd.oasis.opendocument.presentation-template',
      'ods' => 'application/vnd.oasis.opendocument.spreadsheet',
      'ots' => 'application/vnd.oasis.opendocument.spreadsheet-template',
      'odt' => 'application/vnd.oasis.opendocument.text',
      'odm' => 'application/vnd.oasis.opendocument.text-master',
      'ott' => 'application/vnd.oasis.opendocument.text-template',
      'oth' => 'application/vnd.oasis.opendocument.text-web',
      'docm' => 'application/vnd.ms-word.document.macroEnabled.12',
      'docx' => 'application/vnd.openxmlformats-officedocument.wordprocessingml.document',
      'dotm' => 'application/vnd.ms-word.template.macroEnabled.12',
      'dotx' => 'application/vnd.openxmlformats-officedocument.wordprocessingml.template',
      'potm' => 'application/vnd.ms-powerpoint.template.macroEnabled.12',
      'potx' => 'application/vnd.openxmlformats-officedocument.presentationml.template',
      'ppam' => 'application/vnd.ms-powerpoint.addin.macroEnabled.12',
      'ppsm' => 'application/vnd.ms-powerpoint.slideshow.macroEnabled.12',
      'ppsx' => 'application/vnd.openxmlformats-officedocument.presentationml.slideshow',
      'pptm' => 'application/vnd.ms-powerpoint.presentation.macroEnabled.12',
      'pptx' => 'application/vnd.openxmlformats-officedocument.presentationml.presentation',
      'xlam' => 'application/vnd.ms-excel.addin.macroEnabled.12',
      'xlsb' => 'application/vnd.ms-excel.sheet.binary.macroEnabled.12',
      'xlsm' => 'application/vnd.ms-excel.sheet.macroEnabled.12',
      'xlsx' => 'application/vnd.openxmlformats-officedocument.spreadsheetml.sheet',
      'xltm' => 'application/vnd.ms-excel.template.macroEnabled.12',
      'xltx' => 'application/vnd.openxmlformats-officedocument.spreadsheetml.template',
      'cod' => 'application/vnd.rim.cod',
      'mmf' => 'application/vnd.smaf',
      'sdc' => 'application/vnd.stardivision.calc',
      'sds' => 'application/vnd.stardivision.chart',
      'sda' => 'application/vnd.stardivision.draw',
      'sdd' => 'application/vnd.stardivision.impress',
      'sdf' => 'application/vnd.stardivision.math',
      'sdw' => 'application/vnd.stardivision.writer',
      'sgl' => 'application/vnd.stardivision.writer-global',
      'sxc' => 'application/vnd.sun.xml.calc',
      'stc' => 'application/vnd.sun.xml.calc.template',
      'sxd' => 'application/vnd.sun.xml.draw',
      'std' => 'application/vnd.sun.xml.draw.template',
      'sxi' => 'application/vnd.sun.xml.impress',
      'sti' => 'application/vnd.sun.xml.impress.template',
      'sxm' => 'application/vnd.sun.xml.math',
      'sxw' => 'application/vnd.sun.xml.writer',
      'sxg' => 'application/vnd.sun.xml.writer.global',
      'stw' => 'application/vnd.sun.xml.writer.template',
      'sis' => 'application/vnd.symbian.install',
      'vsd' => 'application/vnd.visio',
      'wbxml' => 'application/vnd.wap.wbxml',
      'wmlc' => 'application/vnd.wap.wmlc',
      'wmlsc' => 'application/vnd.wap.wmlscriptc',
      'wk' => 'application/x-123',
      '7z' => 'application/x-7z-compressed',
      'abw' => 'application/x-abiword',
      'dmg' => 'application/x-apple-diskimage',
      'bcpio' => 'application/x-bcpio',
      'torrent' => 'application/x-bittorrent',
      'cab' => 'application/x-cab',
      'cbr' => 'application/x-cbr',
      'cbz' => 'application/x-cbz',
      'cdf' => 'application/x-cdf',
      'vcd' => 'application/x-cdlink',
      'pgn' => 'application/x-chess-pgn',
      'cpio' => 'application/x-cpio',
      'csh' => 'text/x-csh',
      'deb|udeb' => 'application/x-debian-package',
      'dcr|dir|dxr' => 'application/x-director',
      'dms' => 'application/x-dms',
      'wad' => 'application/x-doom',
      'dvi' => 'application/x-dvi',
      'rhtml' => 'application/x-httpd-eruby',
      'flac' => 'application/x-flac',
      'pfa|pfb|gsf|pcf|pcf.Z' => 'application/x-font',
      'mm' => 'application/x-freemind',
      'gnumeric' => 'application/x-gnumeric',
      'sgf' => 'application/x-go-sgf',
      'gcf' => 'application/x-graphing-calculator',
      'gtar|tgz|taz' => 'application/x-gtar',
      'hdf' => 'application/x-hdf',
      'phtml|pht|php' => 'application/x-httpd-php',
      'phps' => 'application/x-httpd-php-source',
      'php3' => 'application/x-httpd-php3',
      'php3p' => 'application/x-httpd-php3-preprocessed',
      'php4' => 'application/x-httpd-php4',
      'ica' => 'application/x-ica',
      'ins|isp' => 'application/x-internet-signup',
      'iii' => 'application/x-iphone',
      'iso' => 'application/x-iso9660-image',
      'jnlp' => 'application/x-java-jnlp-file',
      'js' => 'application/x-javascript',
      'jmz' => 'application/x-jmol',
      'chrt' => 'application/x-kchart',
      'kil' => 'application/x-killustrator',
      'skp|skd|skt|skm' => 'application/x-koan',
      'kpr|kpt' => 'application/x-kpresenter',
      'ksp' => 'application/x-kspread',
      'kwd|kwt' => 'application/x-kword',
      'latex' => 'application/x-latex',
      'lha' => 'application/x-lha',
      'lyx' => 'application/x-lyx',
      'lzh' => 'application/x-lzh',
      'lzx' => 'application/x-lzx',
      'frm|maker|frame|fm|fb|book|fbdoc' => 'application/x-maker',
      'mif' => 'application/x-mif',
      'wmd' => 'application/x-ms-wmd',
      'wmz' => 'application/x-ms-wmz',
      'com|exe|bat|dll' => 'application/x-msdos-program',
      'msi' => 'application/x-msi',
      'nc' => 'application/x-netcdf',
      'pac' => 'application/x-ns-proxy-autoconfig',
      'nwc' => 'application/x-nwc',
      'o' => 'application/x-object',
      'oza' => 'application/x-oz-application',
      'p7r' => 'application/x-pkcs7-certreqresp',
      'crl' => 'application/x-pkcs7-crl',
      'pyc|pyo' => 'application/x-python-code',
      'qtl' => 'application/x-quicktimeplayer',
      'rpm' => 'application/x-redhat-package-manager',
      'sh' => 'text/x-sh',
      'shar' => 'application/x-shar',
      'swf|swfl' => 'application/x-shockwave-flash',
      'sit|sitx' => 'application/x-stuffit',
      'sv4cpio' => 'application/x-sv4cpio',
      'sv4crc' => 'application/x-sv4crc',
      'tar' => 'application/x-tar',
      'tcl' => 'application/x-tcl',
      'gf' => 'application/x-tex-gf',
      'pk' => 'application/x-tex-pk',
      'texinfo|texi' => 'application/x-texinfo',
      '~|%|bak|old|sik' => 'application/x-trash',
      't|tr|roff' => 'application/x-troff',
      'man' => 'application/x-troff-man',
      'me' => 'application/x-troff-me',
      'ms' => 'application/x-troff-ms',
      'ustar' => 'application/x-ustar',
      'src' => 'application/x-wais-source',
      'wz' => 'application/x-wingz',
      'crt' => 'application/x-x509-ca-cert',
      'xcf' => 'application/x-xcf',
      'fig' => 'application/x-xfig',
      'xpi' => 'application/x-xpinstall',
      'au|snd' => 'audio/basic',
      'mid|midi|kar' => 'audio/midi',
      'mpga|mpega|mp2|mp3|m4a' => 'audio/mpeg',
      'f4a|f4b' => 'audio/mp4',
      'm3u' => 'audio/x-mpegurl',
      'oga|spx' => 'audio/ogg',
      'sid' => 'audio/prs.sid',
      'aif|aiff|aifc' => 'audio/x-aiff',
      'gsm' => 'audio/x-gsm',
      'wma' => 'audio/x-ms-wma',
      'wax' => 'audio/x-ms-wax',
      'ra|rm|ram' => 'audio/x-pn-realaudio',
      'ra' => 'audio/x-realaudio',
      'pls' => 'audio/x-scpls',
      'sd2' => 'audio/x-sd2',
      'wav' => 'audio/x-wav',
      'alc' => 'chemical/x-alchemy',
      'cac|cache' => 'chemical/x-cache',
      'csf' => 'chemical/x-cache-csf',
      'cbin|cascii|ctab' => 'chemical/x-cactvs-binary',
      'cdx' => 'chemical/x-cdx',
      'cer' => 'chemical/x-cerius',
      'c3d' => 'chemical/x-chem3d',
      'chm' => 'chemical/x-chemdraw',
      'cif' => 'chemical/x-cif',
      'cmdf' => 'chemical/x-cmdf',
      'cml' => 'chemical/x-cml',
      'cpa' => 'chemical/x-compass',
      'bsd' => 'chemical/x-crossfire',
      'csml|csm' => 'chemical/x-csml',
      'ctx' => 'chemical/x-ctx',
      'cxf|cef' => 'chemical/x-cxf',
      'emb|embl' => 'chemical/x-embl-dl-nucleotide',
      'spc' => 'chemical/x-galactic-spc',
      'inp|gam|gamin' => 'chemical/x-gamess-input',
      'fch|fchk' => 'chemical/x-gaussian-checkpoint',
      'cub' => 'chemical/x-gaussian-cube',
      'gau|gjc|gjf' => 'chemical/x-gaussian-input',
      'gal' => 'chemical/x-gaussian-log',
      'gcg' => 'chemical/x-gcg8-sequence',
      'gen' => 'chemical/x-genbank',
      'hin' => 'chemical/x-hin',
      'istr|ist' => 'chemical/x-isostar',
      'jdx|dx' => 'chemical/x-jcamp-dx',
      'kin' => 'chemical/x-kinemage',
      'mcm' => 'chemical/x-macmolecule',
      'mmd|mmod' => 'chemical/x-macromodel-input',
      'mol' => 'chemical/x-mdl-molfile',
      'rd' => 'chemical/x-mdl-rdfile',
      'rxn' => 'chemical/x-mdl-rxnfile',
      'sd|sdf' => 'chemical/x-mdl-sdfile',
      'tgf' => 'chemical/x-mdl-tgf',
      'mcif' => 'chemical/x-mmcif',
      'mol2' => 'chemical/x-mol2',
      'b' => 'chemical/x-molconn-Z',
      'gpt' => 'chemical/x-mopac-graph',
      'mop|mopcrt|mpc|dat|zmt' => 'chemical/x-mopac-input',
      'moo' => 'chemical/x-mopac-out',
      'mvb' => 'chemical/x-mopac-vib',
      'asn' => 'chemical/x-ncbi-asn1-spec',
      'prt|ent' => 'chemical/x-ncbi-asn1-ascii',
      'val|aso' => 'chemical/x-ncbi-asn1-binary',
      'pdb|ent' => 'chemical/x-pdb',
      'ros' => 'chemical/x-rosdal',
      'sw' => 'chemical/x-swissprot',
      'vms' => 'chemical/x-vamas-iso14976',
      'vmd' => 'chemical/x-vmd',
      'xtel' => 'chemical/x-xtel',
      'xyz' => 'chemical/x-xyz',
      'gif' => 'image/gif',
      'ief' => 'image/ief',
      'jpeg|jpg|jpe' => 'image/jpeg',
      'pcx' => 'image/pcx',
      'png' => 'image/png',
      'svg|svgz' => 'image/svg+xml',
      'tiff|tif' => 'image/tiff',
      'djvu|djv' => 'image/vnd.djvu',
      'wbmp' => 'image/vnd.wap.wbmp',
      'ras' => 'image/x-cmu-raster',
      'cdr' => 'image/x-coreldraw',
      'pat' => 'image/x-coreldrawpattern',
      'cdt' => 'image/x-coreldrawtemplate',
      'ico' => 'image/x-icon',
      'art' => 'image/x-jg',
      'jng' => 'image/x-jng',
      'bmp' => 'image/x-ms-bmp',
      'psd' => 'image/x-photoshop',
      'pnm' => 'image/x-portable-anymap',
      'pbm' => 'image/x-portable-bitmap',
      'pgm' => 'image/x-portable-graymap',
      'ppm' => 'image/x-portable-pixmap',
      'rgb' => 'image/x-rgb',
      'xbm' => 'image/x-xbitmap',
      'xpm' => 'image/x-xpixmap',
      'xwd' => 'image/x-xwindowdump',
      'eml' => 'message/rfc822',
      'igs|iges' => 'model/iges',
      'msh|mesh|silo' => 'model/mesh',
      'wrl|vrml' => 'model/vrml',
      'ics|icz' => 'text/calendar',
      'css' => 'text/css',
      'csv' => 'text/csv',
      '323' => 'text/h323',
      'html|htm|shtml' => 'text/html',
      'uls' => 'text/iuls',
      'mml' => 'text/mathml',
      'asc|txt|text|pot' => 'text/plain',
      'rtx' => 'text/richtext',
      'sct|wsc' => 'text/scriptlet',
      'tm|ts' => 'text/texmacs',
      'tsv' => 'text/tab-separated-values',
      'jad' => 'text/vnd.sun.j2me.app-descriptor',
      'wml' => 'text/vnd.wap.wml',
      'wmls' => 'text/vnd.wap.wmlscript',
      'bib' => 'text/x-bibtex',
      'boo' => 'text/x-boo',
      'h++|hpp|hxx|hh' => 'text/x-c++hdr',
      'c++|cpp|cxx|cc' => 'text/x-c++src',
      'h' => 'text/x-chdr',
      'htc' => 'text/x-component',
      'c' => 'text/x-csrc',
      'd' => 'text/x-dsrc',
      'diff|patch' => 'text/x-diff',
      'hs' => 'text/x-haskell',
      'java' => 'text/x-java',
      'lhs' => 'text/x-literate-haskell',
      'moc' => 'text/x-moc',
      'p|pas' => 'text/x-pascal',
      'gcd' => 'text/x-pcs-gcd',
      'pl|pm' => 'text/x-perl',
      'py' => 'text/x-python',
      'etx' => 'text/x-setext',
      'tcl|tk' => 'text/x-tcl',
      'tex|ltx|sty|cls' => 'text/x-tex',
      'vcs' => 'text/x-vcalendar',
      'vcf' => 'text/x-vcard',
      '3gp' => 'video/3gpp',
      'dl' => 'video/dl',
      'dif|dv' => 'video/dv',
      'fli' => 'video/fli',
      'gl' => 'video/gl',
      'mpeg|mpg|mpe' => 'video/mpeg',
      'mp4|f4v|f4p' => 'video/mp4',
      'flv' => 'video/x-flv',
      'ogv' => 'video/ogg',
      'qt|mov' => 'video/quicktime',
      'mxu' => 'video/vnd.mpegurl',
      'lsf|lsx' => 'video/x-la-asf',
      'mng' => 'video/x-mng',
      'asf|asx' => 'video/x-ms-asf',
      'wm' => 'video/x-ms-wm',
      'wmv' => 'video/x-ms-wmv',
      'wmx' => 'video/x-ms-wmx',
      'wvx' => 'video/x-ms-wvx',
      'avi' => 'video/x-msvideo',
      'movie' => 'video/x-sgi-movie',
      'ice' => 'x-conference/x-cooltalk',
      'sisx' => 'x-epoc/x-sisx-app',
      'vrm|vrml|wrl' => 'x-world/x-vrml',
      'xps' => 'application/vnd.ms-xpsdocument',
    ));
  }
  foreach ($mapping as $ext_preg => $mime_match) {
    if (preg_match('!\\.(' . $ext_preg . ')$!i', $filename)) {
      return $mime_match;
    }
  }
  return 'application/octet-stream';
}

/**
 * @} End of "defgroup file".
 */

Functions

Namesort descending Description
file_check_directory Checks whether a directory exists and is writable.
file_check_location Check if a file is really located inside $directory. Should be used to make sure a file specified is really located within the directory to prevent exploits.
file_check_path Checks path to see if it is a directory, or a dir/file.
file_copy Copies a file to a new location.
file_create_filename Create a full file path from a directory and filename. If a file with the specified name already exists, an alternative will be used.
file_create_htaccess Creates a .htaccess file in the given directory.
file_create_path Make sure the destination is a complete path and resides in the file system directory, if it is not prepend the file system directory.
file_create_url Create the download path to a file.
file_delete Delete a file.
file_destination Determines the destination path for a file depending on how replacement of existing files should be handled.
file_directory_path Determine the default 'files' directory.
file_directory_temp Determine the default temporary directory.
file_download Call modules that implement hook_file_download() to find out if a file is accessible and what headers it should be transferred with. If a module returns -1 drupal_access_denied() will be returned. If one or more modules returned headers the download…
file_download_access Checks that the current user has access to a particular file.
file_download_headers Retrieves headers for a private file download.
file_get_mimetype Determine an Internet Media Type, or MIME type from a filename.
file_htaccess_lines Returns the standard .htaccess lines that Drupal writes to file directories.
file_move Moves a file to a new location.
file_munge_filename Modify a filename as needed for security purposes.
file_save_data Save a string to the specified destination.
file_save_upload Saves a file upload to a new location.
file_scan_directory Finds all files that match a given mask in a given directory.
file_set_status Set the status of a file.
file_space_used Determine total disk space used by a single user or the whole filesystem.
file_transfer Transfer file using http to client. Pipes a file through Drupal to the client.
file_unmunge_filename Undo the effect of upload_munge_filename().
file_upload_max_size Determine the maximum file upload size by querying the PHP settings.
file_validate_extensions Check that the filename ends with an allowed extension. This check is not enforced for the user #1.
file_validate_image_resolution If the file is an image verify that its dimensions are within the specified maximum and minimum dimensions. Non-image files will be ignored.
file_validate_is_image Check that the file is recognized by image_get_info() as an image.
file_validate_name_length Check for files with names longer than we can store in the database.
file_validate_size Check that the file's size is below certain limits. This check is not enforced for the user #1.

Constants

Namesort descending Description
FILE_CREATE_DIRECTORY
FILE_DOWNLOADS_PRIVATE
FILE_DOWNLOADS_PUBLIC
FILE_EXISTS_ERROR
FILE_EXISTS_RENAME
FILE_EXISTS_REPLACE
FILE_MODIFY_PERMISSIONS
FILE_STATUS_PERMANENT
FILE_STATUS_TEMPORARY A files status can be one of two values: temporary or permanent. The status for each file Drupal manages is stored in the {files} tables. If the status is temporary Drupal's file garbage collection will delete the file and remove it from the…

Comments

dimsh’s picture

Many functions in this file uses pass by reference for (from my point of view) no particular reasons, the question is why?

- to save the caller a few lines of code ??, not a pro. style.
- to ease the development ??, it does not.

see the file_copy(&$source); function, apparently, the passed source object (or string) &$source is blown up completely in that function, you prepare a $file object, pass it to file_copy() and you will never see it again, unless you have previously saved it.

Professionally, there is no point from passing by reference here, I know all objects are passed by ref by default, but here (in file_copy(&$source);), destructing the passed object is intended for no particular reason.

- it does not save memory.
- nor it makes the code smarter.

Also, file.inc, does not define or create any hooks for files operations (maybe there is just one), the most hook_lack functionality in Drupal.

Function names also are not descriptive, you see names like:

file_check_path(); // its name is not even related to its task.
file_check_directory(); // the same, it also modify, create, chmod, and set form & status messages!,, looks like the awaiting function all developers dreamed of.

Writing a new functions instead of those in file.inc however never help, since I need to modify all contributed modules code to adapt.

aidanlis’s picture

Variables are passed by reference because they are modified by the called function, and that modification needs to be passed back to the caller.

For example, $dir = "hello/"; file_check_directory($dir); echo $dir; will result in "sites/default/hello".

I don't disagree that some of the API is a little convoluted, the function naming especially, but you seem to have a fundamental misunderstanding of why references are used in this API.

charlie-s’s picture

The object is not "destructed" as I see it. Where are you finding that the function is unsetting the object that it is passed?

It's very useful that I can assign a new file upload to $file, and then do stuff like "file_set_status(&$file)" and have my $file object automatically have the status updated.

BTW objects are only passed as references by default in PHP5, in PHP4 you must use the ampersand thusly: my_function(&$my_var)