Code Coverage for /workspace/src/extensions/Cognate/src/StringHasher.php

1	<?php
2
3	namespace Cognate;
4
5	use InvalidArgumentException;
6	use RuntimeException;
7	use UtfNormal\Validator;
8
9	/**
10	* BIG WARNING!!!!! L(・o・)」
11	* Any changes in this class that result in different hashes will require all tables to be rebuilt.
12	*
13	* @license GPL-2.0-or-later
14	* @author Addshore
15	*/
16	class StringHasher {
17
18	/**
19	* @param string $string
20	*
21	* @throws InvalidArgumentException
22	* @throws RuntimeException if not run on a 64 bit system
23	* @return int a 64 bit SIGNED decimal hash
24	*/
25	public function hash( $string ) {
26	if ( PHP_INT_SIZE !== 8 ) {
27	// 32 bit systems will result in poor hashes
28	throw new RuntimeException( 'Cognate must run on a 64bit system' );
29	}
30	if ( !is_string( $string ) ) {
31	throw new InvalidArgumentException(
32	'Tried to hash a non string value.'
33	);
34	}
35
36	$string = Validator::toNFC( $string );
37
38	return $this->hex2int(
39	substr(
40	hash( 'sha256', $string ),
41	0,
42	16
43	)
44	);
45	}
46
47	/**
48	* Replacement for the php hexdec function.
49	* hexdec( 'FFFFFFFFFFFFFFFF' ) === hexdec( 'FFFFFFFFFFFFFFF0' )
50	* There are gaps in high values that would increase the chance of collisions.
51	* So use this replacement instead.
52	*
53	* @param string $hex16
54	*
55	* @return int
56	*/
57	private function hex2int( $hex16 ) {
58	$hexhi = substr( $hex16, 0, 8 );
59	$hexlo = substr( $hex16, 8, 8 );
60
61	$int = hexdec( $hexlo ) \| ( hexdec( $hexhi ) << 32 );
62	return $int;
63	}
64
65	}