Definition of Drupal\Component\Uuid\Php.
<?php
/**
* @file
* Definition of Drupal\Component\Uuid\Php.
*/
namespace Drupal\Component\Uuid;
use Drupal\Component\Utility\Crypt;
/**
* Generates a UUID v4 using PHP code.
*
* Loosely based on Ruby's UUIDTools generate_random logic.
*
* @see http://uuidtools.rubyforge.org/api/classes/UUIDTools/UUID.html
*/
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;
}
}