Jose\Component\Core\Util\Ecc\Util\NumberSize

Complexity

Total Complexity

3

Size/Duplication

Total Lines	27
Duplicated Lines	0 %

Coupling/Cohesion

Components	0
Dependencies	1

Importance

Changes

0

1 Method

Rating	Name	Duplication	Size	Complexity
A	bnNumBits()	0	15	3

<?php

namespace Jose\Component\Core\Util\Ecc\Util;

use Jose\Component\Core\Util\Ecc\Math\GmpMath;

final class NumberSize
{
    /**
     * Returns the number of bits used to store this number. Non-singicant upper bits are not counted.
     *
     * @param  GmpMath $adapter
     * @param  \GMP             $x
     * @return number
     *
     * @link https://www.openssl.org/docs/crypto/BN_num_bytes.html
     */
    public static function bnNumBits(GmpMath $adapter, \GMP $x)
    {
        $zero = gmp_init(0, 10);
        if ($adapter->equals($x, $zero)) {
            return 0;
        }

        $log2 = 0;
        while (false === $adapter->equals($x, $zero)) {
            $x = $adapter->rightShift($x, 1);
            $log2++;
        }

        return $log2 ;
    }
}