hash_wrapper.module

<?php

/**
 * Implements hook_stream_wrappers().
 */
function hash_wrapper_stream_wrappers() {
  return array(
    'hash' => array(
      'name' => t('Hashed files'),
      'class' => 'HashStreamWrapper',
      'description' => t('Hashed local files served by the webserver.'),
      'type' => STREAM_WRAPPERS_LOCAL_NORMAL,
    ),
  );
}

class HashStreamWrapper extends DrupalPublicStreamWrapper {
  /**
   * Return the local filesystem path.
   *
   * Minimally modified DrupalPublicStreamWrapper::getLocalPath to call
   * $this->uriTarget() instead of file_uri_target().
   *
   * @param $uri
   *   Optional URI, supplied when doing a move or rename.
   */
  protected function getLocalPath($uri = NULL) {
    if (!isset($uri)) {
      $uri = $this->uri;
    }
    $basedir = $this->getDirectoryPath();
    $path = $basedir . '/' . $this->uriTarget($uri, $basedir);
    $realpath = realpath($path);
    if (!$realpath) {
      // This file does not yet exist.
      $realpath = realpath(dirname($path)) . '/' . basename($path);
    }
    $directory = realpath($basedir);
    if (!$realpath || !$directory || strpos($realpath, $directory) !== 0) {
      return FALSE;
    }
    return $realpath;
  }

  /**
   * Overrides getExternalUrl().
   *
   * Minimally modified DrupalPublicStreamWrapper::getExternalUrl() to call
   * $this->uriTarget() instead of file_uri_target().
   *
   * Return the HTML URI of a public file.
   */
  function getExternalUrl() {
    $basedir = self::getDirectoryPath();
    $path = str_replace('\\', '/', self::uriTarget($this->uri, $basedir));
    return $GLOBALS['base_url'] . "/$basedir/$path";
  }

  /**
   * Support for mkdir().
   *
   * Minimall modified DrupalPublicStreamWrapper::mkdir() to call
   * $this->uriTarget() instead of file_uri_target().
   *
   * @param $uri
   *   A string containing the URI to the directory to create.
   * @param $mode
   *   Permission flags - see mkdir().
   * @param $options
   *   A bit mask of STREAM_REPORT_ERRORS and STREAM_MKDIR_RECURSIVE.
   * @return
   *   TRUE if directory was successfully created.
   * @see http://php.net/manual/en/streamwrapper.mkdir.php
   */
  public function mkdir($uri, $mode, $options) {
    $this->uri = $uri;
    $recursive = (bool)($options & STREAM_MKDIR_RECURSIVE);
    if ($recursive) {
      // $this->getLocalPath() fails if $uri has multiple levels of directories
      // that do not yet exist.
      $basedir = $this->getDirectoryPath();
      $localpath = $basedir . '/' . $this->uriTarget($uri, $basedir);
    }
    else {
      $localpath = $this->getLocalPath($uri);
    }
    if ($options & STREAM_REPORT_ERRORS) {
      return mkdir($localpath, $mode, $recursive);
    }
    else {
      return @mkdir($localpath, $mode, $recursive);
    }
  }

  /**
   * Returns the target of a URI (e.g. a stream).
   *
   * @param $uri
   *   A stream, referenced as "scheme://target".
   * @return
   *   A string containing the target (path), or FALSE if none.
   *   For example, the URI "public://sample/test.txt" would return
   *   "sample/test.txt".
   */
  function uriTarget($uri, $basedir) {
    $filepath = file_uri_target($uri);
    // If all we got is hash://directory or even just hash:// then we can't
    // really continue.
    if (!$filepath || strpos($filepath, '.') === FALSE) {
      return $filepath;
    }
    $directory = dirname($filepath);
    $dir_parts = explode('/', $directory);
    if (count($dir_parts) >= 2 && strlen(array_pop($dir_parts)) == 2 && strlen(array_pop($dir_parts)) == 2) {
      return $filepath;
    }
    $file_parts = explode('.', $filepath);
    $count = count($file_parts);
    $extension = ($count > 1) ? '.' . array_pop($file_parts) : '';
    $basedir .= "/$directory";

    // Remove styles/$style/hash path before generating the hash.
    $filepath = preg_replace('/styles\/.+\/hash\//', '', $filepath);

    $target = md5($filepath) . $extension;
    $level1 = "$target[0]$target[1]";
    $level2 = "$target[2]$target[3]";
    if (!is_dir("$basedir/$level1/$level2")) {
      drupal_mkdir("$basedir/$level1/$level2", NULL, TRUE);
    }

    return "$directory/$level1/$level2/$target";
  }
}