meta/db-reader/src/MaxMind/Db/Reader/Util.php

33 lines
812 B
PHP

<?php
declare(strict_types=1);
namespace MaxMind\Db\Reader;
class Util
{
/**
* @param resource $stream
*/
public static function read($stream, int $offset, int $numberOfBytes): string
{
if ($numberOfBytes === 0) {
return '';
}
if (fseek($stream, $offset) === 0) {
$value = fread($stream, $numberOfBytes);
// We check that the number of bytes read is equal to the number
// asked for. We use ftell as getting the length of $value is
// much slower.
if ($value !== false && ftell($stream) - $offset === $numberOfBytes) {
return $value;
}
}
throw new InvalidDatabaseException(
'The MaxMind DB file contains bad data'
);
}
}