<?php
declare(strict_types=1);
/*
* The MIT License (MIT)
*
* Copyright (c) 2018-2020 Spomky-Labs
*
* This software may be modified and distributed under the terms
* of the MIT license. See the LICENSE file for details.
*/
namespace CBOR;
use InvalidArgumentException;
use RuntimeException;
final class StringStream implements Stream
{
/**
* @var resource
*/
private $resource;
public function __construct(string $data)
{
$resource = fopen('php://memory', 'rb+');
if (false === $resource) {
throw new RuntimeException('Unable to open the memory');
}
$result = fwrite($resource, $data);
if (false === $result) {
throw new RuntimeException('Unable to write the memory');
}
$result = rewind($resource);
if (false === $result) {
throw new RuntimeException('Unable to rewind the memory');
}
$this->resource = $resource;
}
public function read(int $length): string
{
if (0 === $length) {
return '';
}
$data = fread($this->resource, $length);
if (false === $data) {
throw new RuntimeException('Unable to read the memory');
}
if (mb_strlen($data, '8bit') !== $length) {
throw new InvalidArgumentException(sprintf('Out of range. Expected: %d, read: %d.', $length, mb_strlen($data, '8bit')));
}
return $data;
}
}