37 lines
1010 B
PHP
37 lines
1010 B
PHP
<?php
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declare(strict_types=1);
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namespace Plumrocket\GeoIPLookup\Library\Mmdb\Reader;
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class Util
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{
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/**
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* @param resource $stream
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* @param int $offset
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* @param int<0, max> $numberOfBytes
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* @return string
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* @throws \Plumrocket\GeoIPLookup\Library\Mmdb\Reader\InvalidDatabaseException
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*/
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public static function read($stream, int $offset, int $numberOfBytes): string
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{
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if ($numberOfBytes === 0) {
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return '';
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}
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if (fseek($stream, $offset) === 0) {
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$value = fread($stream, $numberOfBytes);
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// We check that the number of bytes read is equal to the number
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// asked for. We use ftell as getting the length of $value is
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// much slower.
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if ($value !== false && ftell($stream) - $offset === $numberOfBytes) {
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return $value;
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}
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}
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throw new InvalidDatabaseException(
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'The MaxMind DB file contains bad data'
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);
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}
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}
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