diff options
Diffstat (limited to '')
-rw-r--r-- | vendor/setasign/fpdi/src/PdfParser/Filter/Flate.php | 86 |
1 files changed, 86 insertions, 0 deletions
diff --git a/vendor/setasign/fpdi/src/PdfParser/Filter/Flate.php b/vendor/setasign/fpdi/src/PdfParser/Filter/Flate.php new file mode 100644 index 0000000..b8f79d1 --- /dev/null +++ b/vendor/setasign/fpdi/src/PdfParser/Filter/Flate.php @@ -0,0 +1,86 @@ +<?php + +/** + * This file is part of FPDI + * + * @package setasign\Fpdi + * @copyright Copyright (c) 2020 Setasign GmbH & Co. KG (https://www.setasign.com) + * @license http://opensource.org/licenses/mit-license The MIT License + */ + +namespace setasign\Fpdi\PdfParser\Filter; + +/** + * Class for handling zlib/deflate encoded data + */ +class Flate implements FilterInterface +{ + /** + * Checks whether the zlib extension is loaded. + * + * Used for testing purpose. + * + * @return boolean + * @internal + */ + protected function extensionLoaded() + { + return \extension_loaded('zlib'); + } + + /** + * Decodes a flate compressed string. + * + * @param string|false $data The input string + * @return string + * @throws FlateException + */ + public function decode($data) + { + if ($this->extensionLoaded()) { + $oData = $data; + $data = (($data !== '') ? @\gzuncompress($data) : ''); + if ($data === false) { + // let's try if the checksum is CRC32 + $fh = fopen('php://temp', 'w+b'); + fwrite($fh, "\x1f\x8b\x08\x00\x00\x00\x00\x00" . $oData); + stream_filter_append($fh, 'zlib.inflate', STREAM_FILTER_READ, ['window' => 30]); + fseek($fh, 0); + $data = @stream_get_contents($fh); + fclose($fh); + + if ($data) { + return $data; + } + + // Try this fallback + $tries = 0; + + $oDataLen = strlen($oData); + while ($tries < 6 && ($data === false || (strlen($data) < ($oDataLen - $tries - 1)))) { + $data = @(gzinflate(substr($oData, $tries))); + $tries++; + } + + // let's use this fallback only if the $data is longer than the original data + if (strlen($data) > ($oDataLen - $tries - 1)) { + return $data; + } + + if (!$data) { + throw new FlateException( + 'Error while decompressing stream.', + FlateException::DECOMPRESS_ERROR + ); + } + } + } else { + throw new FlateException( + 'To handle FlateDecode filter, enable zlib support in PHP.', + FlateException::NO_ZLIB + ); + } + + return $data; + } +} |