Test project for media files management.
<?php
/*
* This file is part of the Symfony package.
*
* (c) Fabien Potencier <fabien@symfony.com>
*
* For the full copyright and license information, please view the LICENSE
* file that was distributed with this source code.
*/
namespace Symfony\Component\Uid;
/**
* A v4 UUID contains a 122-bit random number.
*
* @author Grégoire Pineau <lyrixx@lyrixx.info>
*/
class UuidV4 extends Uuid
{
protected const TYPE = 4;
public function __construct(?string $uuid = null)
{
if (null === $uuid) {
// Generate 36 random hex characters (144 bits)
// xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx
$uuid = bin2hex(random_bytes(18));
// Insert dashes to match the UUID format
// xxxxxxxx-xxxx-xxxx-xxxx-xxxxxxxxxxxx
$uuid[8] = $uuid[13] = $uuid[18] = $uuid[23] = '-';
// Set the UUID version to 4
// xxxxxxxx-xxxx-4xxx-xxxx-xxxxxxxxxxxx
$uuid[14] = '4';
// Set the UUID variant: the 19th char must be in [8, 9, a, b]
// xxxxxxxx-xxxx-4xxx-?xxx-xxxxxxxxxxxx
$uuid[19] = ['8', '9', 'a', 'b', '8', '9', 'a', 'b', 'c' => '8', 'd' => '9', 'e' => 'a', 'f' => 'b'][$uuid[19]] ?? $uuid[19];
$this->uid = $uuid;
} else {
parent::__construct($uuid, true);
}
}
}