class Uuid

backdrop_class_list in core/includes/bootstrap.classes.inc

Lists all the classes used by Backdrop core.

Block::toArray in core/modules/layout/includes/block.class.inc

Convert the configuration of this block to an array for storage.

Block::__construct in core/modules/layout/includes/block.class.inc

Create a new Block object.

system_update_1025 in core/modules/system/system.install

Convert block positioning and configuration to the default layout.

class Uuid {

  /**
   * Holds the UUID implementation.
   */
  protected $plugin;

  /**
   * This constructor instantiates the correct UUID object.
   */
  public function __construct() {
    $class = $this->determinePlugin();
    $this->plugin = new $class();
  }

  /**
   * Generates an universally unique identifier.
   *
   * @see UuidInterface::generate()
   */
  public function generate() {
    return $this->plugin->generate();
  }

  /**
   * Check that a string appears to be in the format of a UUID.
   *
   * Plugins should not implement validation, since UUIDs should be in a
   * consistent format across all plugins.
   *
   * @param $uuid
   *   The string to test.
   *
   * @return
   *   TRUE if the string is well formed.
   */
  public function isValid($uuid) {
    return preg_match("/^[0-9a-f]{8}-([0-9a-f]{4}-){3}[0-9a-f]{12}$/", $uuid);
  }

  /**
   * Determines the optimal implementation to use for generating UUIDs.
   *
   * The selection is made based on the enabled PHP extensions with the
   * most performant available option chosen.
   *
   * @return
   *  The class name for the optimal UUID generator.
   */
  protected function determinePlugin() {
    static $plugin;
    if (!empty($plugin)) {
      return $plugin;
    }

    $plugin = 'UuidPhp';

    // Debian/Ubuntu uses the (broken) OSSP extension as their UUID
    // implementation. The OSSP implementation is not compatible with the
    // PECL functions.
    if (function_exists('uuid_create') && !function_exists('uuid_make')) {
      $plugin = 'UuidPecl';
    }
    // Try to use the COM implementation for Windows users.
    elseif (function_exists('com_create_guid')) {
      $plugin = 'UuidCom';
    }
    return $plugin;
  }
}