<?php
declare(strict_types=1);
/*
Copyright (c) 2003, 2005, 2006, 2009 Danilo Segan <danilo@kvota.net>.
Copyright (c) 2016 Michal Čihař <michal@cihar.com>
This file is part of MoTranslator.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License along
with this program; if not, write to the Free Software Foundation, Inc.,
51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/
namespace PhpMyAdmin\MoTranslator;
use function file_get_contents;
use function strlen;
use function substr;
use function unpack;
use const PHP_INT_MAX;
/**
* Simple wrapper around string buffer for
* random access and values parsing.
*/
class StringReader
{
/** @var string */
private $string;
/** @var int */
private $length;
/**
* @param string $filename Name of file to load
*/
public function __construct(string $filename)
{
$this->string = (string) file_get_contents($filename);
$this->length = strlen($this->string);
}
/**
* Read number of bytes from given offset.
*
* @param int $pos Offset
* @param int $bytes Number of bytes to read
*/
public function read(int $pos, int $bytes): string
{
if ($pos + $bytes > $this->length) {
throw new ReaderException('Not enough bytes!');
}
$data = substr($this->string, $pos, $bytes);
return $data === false ? '' : $data;
}
/**
* Reads a 32bit integer from the stream.
*
* @param string $unpack Unpack string
* @param int $pos Position
*
* @return int Integer from the stream
*/
public function readint(string $unpack, int $pos): int
{
$data = unpack($unpack, $this->read($pos, 4));
if ($data === false) {
return PHP_INT_MAX;
}
$result = $data[1];
/* We're reading unsigned int, but PHP will happily
* give us negative number on 32-bit platforms.
*
* See also documentation:
* https://secure.php.net/manual/en/function.unpack.php#refsect1-function.unpack-notes
*/
return $result < 0 ? PHP_INT_MAX : $result;
}
/**
* Reads an array of integers from the stream.
*
* @param string $unpack Unpack string
* @param int $pos Position
* @param int $count How many elements should be read
*
* @return int[] Array of Integers
*/
public function readintarray(string $unpack, int $pos, int $count): array
{
$data = unpack($unpack . $count, $this->read($pos, 4 * $count));
if ($data === false) {
return [];
}
return $data;
}
}