Search moodle.org's
Developer Documentation

See Release Notes
Long Term Support Release

  • Bug fixes for general core bugs in 4.1.x will end 13 November 2023 (12 months).
  • Bug fixes for security issues in 4.1.x will end 10 November 2025 (36 months).
  • PHP version: minimum PHP 7.4.0 Note: minimum PHP version has increased since Moodle 4.0. PHP 8.0.x is supported too.
   1  <?php
   2  /**
   3   * Class for generating RFC 4122 UUIDs. Usage:
   4   *
   5   * <code>
   6   * $uuid = (string)new Horde_Support_Uuid;
   7   * </code>
   8   *
   9   * Copyright 2008-2017 Horde LLC (http://www.horde.org/)
  10   *
  11   * @category   Horde
  12   * @package    Support
  13   * @license    http://www.horde.org/licenses/bsd
  14   */
  15  class Horde_Support_Uuid
  16  {
  17      /**
  18       * Generated UUID
  19       * @var string
  20       */
  21      private $_uuid;
  22  
  23      /**
  24       * New UUID.
  25       */
  26      public function __construct()
  27      {
  28          $this->generate();
  29      }
  30  
  31      /**
  32       * Generate a 36-character RFC 4122 UUID, without the urn:uuid: prefix.
  33       *
  34       * @see http://www.ietf.org/rfc/rfc4122.txt
  35       * @see http://labs.omniti.com/alexandria/trunk/OmniTI/Util/UUID.php
  36       */
  37      public function generate()
  38      {
  39          $this->_uuid = null;
  40          if (extension_loaded('uuid')) {
  41              if (function_exists('uuid_export')) {
  42                  // UUID extension from http://www.ossp.org/pkg/lib/uuid/
  43                  if (uuid_create($ctx) == UUID_RC_OK &&
  44                      uuid_make($ctx, UUID_MAKE_V4) == UUID_RC_OK &&
  45                      uuid_export($ctx, UUID_FMT_STR, $str) == UUID_RC_OK) {
  46                      $this->_uuid = $str;
  47                      uuid_destroy($ctx);
  48                  }
  49              } else {
  50                  // UUID extension from http://pecl.php.net/package/uuid
  51                  $this->_uuid = uuid_create();
  52              }
  53          }
  54          if (!$this->_uuid) {
  55              list($time_mid, $time_low) = explode(' ', microtime());
  56              $time_low = (int)$time_low;
  57              $time_mid = (int)substr($time_mid, 2) & 0xffff;
  58              $time_high = mt_rand(0, 0x0fff) | 0x4000;
  59  
  60              $clock = mt_rand(0, 0x3fff) | 0x8000;
  61  
  62              $node_low = function_exists('zend_thread_id')
  63                  ? zend_thread_id()
  64                  : getmypid();
  65              $node_high = isset($_SERVER['SERVER_ADDR'])
  66                  ? ip2long($_SERVER['SERVER_ADDR'])
  67                  : crc32(php_uname());
  68              $node = bin2hex(pack('nN', $node_low, $node_high));
  69  
  70              $this->_uuid = sprintf('%08x-%04x-%04x-%04x-%s',
  71                  $time_low, $time_mid, $time_high, $clock, $node);
  72          }
  73      }
  74  
  75      /**
  76       * Cooerce to string.
  77       *
  78       * @return string  UUID.
  79       */
  80      public function __toString()
  81      {
  82          return $this->_uuid;
  83      }
  84  
  85  }