<?php
/**
* Copyright 2019 Google LLC
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
namespace Google\CRC32;
use Google\CRC32\CRC32;
use Google\CRC32\CRCInterface;
/**
* A CRC32 implementation using hardware acceleration.
*
* This uses the C++ https://github.com/google/crc32c library, thus depends on
* the `crc32c` PHP extension.
*/
final class Google implements CRCInterface
{
public static function supports($algo)
{
return $algo === CRC32::CASTAGNOLI;
}
public function __construct()
{
if (!function_exists('crc32c')) {
throw new \InvalidArgumentException("crc32c function not found. Please load the 'crc32c' extension.");
}
$this->reset();
}
public function reset()
{
$this->crc = hex2bin('00000000');
}
public function update($data)
{
$this->crc = crc32c($data, $this->crc);
}
public function hash($raw_output = null)
{
if ($raw_output === true) {
return $this->crc;
}
return bin2hex($this->crc);
}
public function version()
{
return 'Hardware accelerated (https://github.com/google/crc32c)';
}
}