91 lines
2.4 KiB
PHP
91 lines
2.4 KiB
PHP
<?php
|
|
|
|
/**
|
|
* This file is part of the ramsey/uuid library
|
|
*
|
|
* For the full copyright and license information, please view the LICENSE
|
|
* file that was distributed with this source code.
|
|
*
|
|
* @copyright Copyright (c) Ben Ramsey <ben@benramsey.com>
|
|
* @license http://opensource.org/licenses/MIT MIT
|
|
*/
|
|
|
|
declare(strict_types=1);
|
|
|
|
namespace Ramsey\Uuid\Rfc4122;
|
|
|
|
use Ramsey\Uuid\Exception\InvalidBytesException;
|
|
use Ramsey\Uuid\Uuid;
|
|
|
|
use function decbin;
|
|
use function str_pad;
|
|
use function strlen;
|
|
use function strpos;
|
|
use function substr;
|
|
use function unpack;
|
|
|
|
use const STR_PAD_LEFT;
|
|
|
|
/**
|
|
* Provides common functionality for handling the variant, as defined by RFC 4122
|
|
*
|
|
* @psalm-immutable
|
|
*/
|
|
trait VariantTrait
|
|
{
|
|
/**
|
|
* Returns the bytes that comprise the fields
|
|
*/
|
|
abstract public function getBytes(): string;
|
|
|
|
/**
|
|
* Returns the variant identifier, according to RFC 4122, for the given bytes
|
|
*
|
|
* The following values may be returned:
|
|
*
|
|
* - `0` -- Reserved, NCS backward compatibility.
|
|
* - `2` -- The variant specified in RFC 4122.
|
|
* - `6` -- Reserved, Microsoft Corporation backward compatibility.
|
|
* - `7` -- Reserved for future definition.
|
|
*
|
|
* @link https://tools.ietf.org/html/rfc4122#section-4.1.1 RFC 4122, § 4.1.1: Variant
|
|
*
|
|
* @return int The variant identifier, according to RFC 4122
|
|
*/
|
|
public function getVariant(): int
|
|
{
|
|
if (strlen($this->getBytes()) !== 16) {
|
|
throw new InvalidBytesException('Invalid number of bytes');
|
|
}
|
|
|
|
/** @var array $parts */
|
|
$parts = unpack('n*', $this->getBytes());
|
|
|
|
// $parts[5] is a 16-bit, unsigned integer containing the variant bits
|
|
// of the UUID. We convert this integer into a string containing a
|
|
// binary representation, padded to 16 characters. We analyze the first
|
|
// three characters (three most-significant bits) to determine the
|
|
// variant.
|
|
$binary = str_pad(
|
|
decbin((int) $parts[5]),
|
|
16,
|
|
'0',
|
|
STR_PAD_LEFT
|
|
);
|
|
|
|
$msb = substr($binary, 0, 3);
|
|
|
|
if ($msb === '111') {
|
|
$variant = Uuid::RESERVED_FUTURE;
|
|
} elseif ($msb === '110') {
|
|
$variant = Uuid::RESERVED_MICROSOFT;
|
|
} elseif (strpos($msb, '10') === 0) {
|
|
$variant = Uuid::RFC_4122;
|
|
} else {
|
|
$variant = Uuid::RESERVED_NCS;
|
|
}
|
|
|
|
return $variant;
|
|
}
|
|
}
|