class Php

1. 8.x drupal/core/lib/Drupal/Component/Uuid/Php.php \Drupal\Component\Uuid\Php
2. 8.x drupal/core/modules/php/lib/Drupal/php/Plugin/Filter/Php.php \Drupal\php\Plugin\Filter\Php
3. 8.x drupal/core/modules/php/lib/Drupal/php/Plugin/Condition/Php.php \Drupal\php\Plugin\Condition\Php
4. 8.x drupal/core/modules/views/lib/Drupal/views/Plugin/views/argument_validator/Php.php \Drupal\views\Plugin\views\argument_validator\Php
5. 8.x drupal/core/modules/views/lib/Drupal/views/Plugin/views/argument_default/Php.php \Drupal\views\Plugin\views\argument_default\Php

class Php implements UuidInterface {

  /**
   * Implements Drupal\Component\Uuid\UuidInterface::generate().
   */
  public function generate() {
    $hex = substr(hash('sha256', Crypt::randomBytes(16)), 0, 32);

    // The field names refer to RFC 4122 section 4.1.2.
    $time_low = substr($hex, 0, 8);
    $time_mid = substr($hex, 8, 4);
    $time_hi_and_version = base_convert(substr($hex, 12, 4), 16, 10);
    $time_hi_and_version &= 0xfff;
    $time_hi_and_version |= 4 << 12;
    $clock_seq_hi_and_reserved = base_convert(substr($hex, 16, 4), 16, 10);
    $clock_seq_hi_and_reserved &= 0x3f;
    $clock_seq_hi_and_reserved |= 0x80;
    $clock_seq_low = substr($hex, 20, 2);
    $nodes = substr($hex, 20);
    $uuid = sprintf('%s-%s-%04x-%02x%02x-%s', $time_low, $time_mid, $time_hi_and_version, $clock_seq_hi_and_reserved, $clock_seq_low, $nodes);
    return $uuid;
  }

}