Failed Conditions
Push — master ( e3206a...8d8ce8 )
by Florent
02:45
created

BigInteger::toBytes()   A

Complexity

Conditions 3
Paths 3

Size

Total Lines 12
Code Lines 7

Duplication

Lines 0
Ratio 0 %

Importance

Changes 2
Bugs 0 Features 2
Metric Value
c 2
b 0
f 2
dl 0
loc 12
rs 9.4285
cc 3
eloc 7
nc 3
nop 0
1
<?php
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/*
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 * The MIT License (MIT)
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 *
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 * Copyright (c) 2014-2016 Spomky-Labs
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 *
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 * This software may be modified and distributed under the terms
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 * of the MIT license.  See the LICENSE file for details.
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 */
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namespace Jose\Util;
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use Assert\Assertion;
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final class BigInteger
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{
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    /**
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     * Holds the BigInteger's value.
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     *
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     * @var resource
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     */
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    private $value;
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    /**
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     * Converts base-10 and binary strings (base-256) to BigIntegers.
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     *
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     * @param \GMP|string $value
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     * @param int         $base
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     */
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    private function __construct($value, $base)
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    {
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        if ($value instanceof \GMP) {
0 ignored issues
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Bug introduced by
The class GMP does not exist. Did you forget a USE statement, or did you not list all dependencies?

This error could be the result of:

1. Missing dependencies

PHP Analyzer uses your composer.json file (if available) to determine the dependencies of your project and to determine all the available classes and functions. It expects the composer.json to be in the root folder of your repository.

Are you sure this class is defined by one of your dependencies, or did you maybe not list a dependency in either the require or require-dev section?

2. Missing use statement

PHP does not complain about undefined classes in ìnstanceof checks. For example, the following PHP code will work perfectly fine:

if ($x instanceof DoesNotExist) {
    // Do something.
}

If you have not tested against this specific condition, such errors might go unnoticed.

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34
            $this->value = $value;
0 ignored issues
show
Documentation Bug introduced by
It seems like $value of type object<GMP> is incompatible with the declared type resource of property $value.

Our type inference engine has found an assignment to a property that is incompatible with the declared type of that property.

Either this assignment is in error or the assigned type should be added to the documentation/type hint for that property..

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            return;
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        }
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        $this->value = gmp_init($value, $base);
0 ignored issues
show
Documentation Bug introduced by
It seems like gmp_init($value, $base) of type object<GMP> is incompatible with the declared type resource of property $value.

Our type inference engine has found an assignment to a property that is incompatible with the declared type of that property.

Either this assignment is in error or the assigned type should be added to the documentation/type hint for that property..

Loading history...
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    }
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    /**
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     * @param \GMP $value
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     *
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     * @return \Jose\Util\BigInteger
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     */
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    public static function createFromGMPResource($value)
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    {
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        Assertion::isInstanceOf($value, \GMP::class);
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        return new self($value, 0);
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    }
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    /**
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     * @param string $value
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     *
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     * @return \Jose\Util\BigInteger
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     */
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    public static function createFromBinaryString($value)
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    {
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        Assertion::string($value);
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        $value = '0x'.bin2hex($value);
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        return new self($value, 16);
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    }
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    /**
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     * @param string $value
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     *
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     * @return \Jose\Util\BigInteger
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     */
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    public static function createFromDecimalString($value)
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    {
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        Assertion::string($value);
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        return new self($value, 10);
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    }
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    /**
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     * @param string $value
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     *
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     * @return \Jose\Util\BigInteger
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     */
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    public static function createFromDecimal($value)
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    {
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        Assertion::integer($value);
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        return new self($value, 10);
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    }
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    /**
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     * Converts a BigInteger to a byte string (eg. base-256).
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     *
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     * @return string
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     */
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    public function toBytes()
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    {
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        if (gmp_cmp($this->value, gmp_init(0)) === 0) {
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            return '';
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        }
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        $temp = gmp_strval(gmp_abs($this->value), 16);
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        $temp = (strlen($temp) & 1) ? '0'.$temp : $temp;
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        $temp = hex2bin($temp);
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        return ltrim($temp, chr(0));
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    }
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    /**
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     * Adds two BigIntegers.
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     *
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     *  @param \Jose\Util\BigInteger $y
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     *
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     *  @return \Jose\Util\BigInteger
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     */
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    public function add(BigInteger $y)
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    {
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        $value = gmp_add($this->value, $y->value);
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        return self::createFromGMPResource($value);
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    }
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    /**
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     * Subtracts two BigIntegers.
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     *
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     *  @param \Jose\Util\BigInteger $y
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     *
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     *  @return \Jose\Util\BigInteger
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     */
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    public function subtract(BigInteger $y)
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    {
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        $value = gmp_sub($this->value, $y->value);
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        return self::createFromGMPResource($value);
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    }
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    /**
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     * Multiplies two BigIntegers.
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     *
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     * @param \Jose\Util\BigInteger $x
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     *
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     *  @return \Jose\Util\BigInteger
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     */
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    public function multiply(BigInteger $x)
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    {
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        $value = gmp_mul($this->value, $x->value);
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        return self::createFromGMPResource($value);
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    }
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    /**
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     * Performs modular exponentiation.
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     *
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     * @param \Jose\Util\BigInteger $e
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     * @param \Jose\Util\BigInteger $n
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     *
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     * @return \Jose\Util\BigInteger|bool
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     */
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    public function modPow(BigInteger $e, BigInteger $n)
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    {
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        $value = gmp_powm($this->value, $e->value, $n->value);
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        return self::createFromGMPResource($value);
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    }
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    /**
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     * Performs modular exponentiation.
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     *
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     * @param \Jose\Util\BigInteger $d
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     *
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     * @return \Jose\Util\BigInteger
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     */
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    public function mod(BigInteger $d)
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    {
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        $value = gmp_mod($this->value, $d->value);
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        return self::createFromGMPResource($value);
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    }
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    /**
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     * Calculates modular inverses.
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     *
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     * @param \Jose\Util\BigInteger $n
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     *
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     * @return \Jose\Util\BigInteger|bool
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     */
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    public function modInverse(BigInteger $n)
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    {
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        $value = gmp_invert($this->value, $n->value);
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        return false === $value ? false : self::createFromGMPResource($value);
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    }
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    /**
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     * Compares two numbers.
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     *
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     * @param \Jose\Util\BigInteger $y
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     *
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     * @return int < 0 if $this is less than $y; > 0 if $this is greater than $y, and 0 if they are equal.
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     */
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    public function compare(BigInteger $y)
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    {
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        return gmp_cmp($this->value, $y->value);
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    }
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}
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