925 lines
26 KiB
PHP
925 lines
26 KiB
PHP
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<?php
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/**
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* This file is part of FPDI
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*
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* @package FPDI
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* @copyright Copyright (c) 2017 Setasign - Jan Slabon (https://www.setasign.com)
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* @license http://opensource.org/licenses/mit-license The MIT License
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* @version 1.6.2
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*/
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/**
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* Class pdf_parser
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*/
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class pdf_parser
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{
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/**
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* Type constant
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*
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* @var integer
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*/
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const TYPE_NULL = 0;
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/**
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* Type constant
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*
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* @var integer
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*/
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const TYPE_NUMERIC = 1;
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/**
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* Type constant
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*
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* @var integer
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*/
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const TYPE_TOKEN = 2;
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/**
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* Type constant
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*
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* @var integer
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*/
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const TYPE_HEX = 3;
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/**
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* Type constant
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*
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* @var integer
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*/
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const TYPE_STRING = 4;
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/**
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* Type constant
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*
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* @var integer
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*/
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const TYPE_DICTIONARY = 5;
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/**
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* Type constant
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*
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* @var integer
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*/
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const TYPE_ARRAY = 6;
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/**
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* Type constant
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*
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* @var integer
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*/
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const TYPE_OBJDEC = 7;
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/**
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* Type constant
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*
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* @var integer
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*/
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const TYPE_OBJREF = 8;
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/**
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* Type constant
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*
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* @var integer
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*/
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const TYPE_OBJECT = 9;
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/**
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* Type constant
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*
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* @var integer
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*/
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const TYPE_STREAM = 10;
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/**
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* Type constant
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*
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* @var integer
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*/
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const TYPE_BOOLEAN = 11;
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/**
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* Type constant
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*
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* @var integer
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*/
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const TYPE_REAL = 12;
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/**
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* Define the amount of byte in which the initial keyword of a PDF document should be searched.
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*
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* @var int
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*/
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static public $searchForStartxrefLength = 5500;
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/**
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* Filename
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*
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* @var string
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*/
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public $filename;
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/**
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* File resource
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*
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* @var resource
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*/
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protected $_f;
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/**
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* PDF Context
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*
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* @var pdf_context
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*/
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protected $_c;
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/**
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* xref-Data
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*
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* @var array
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*/
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protected $_xref;
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/**
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* Data of the Root object
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*
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* @var array
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*/
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protected $_root;
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/**
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* PDF version of the loaded document
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*
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* @var string
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*/
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protected $_pdfVersion;
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/**
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* For reading encrypted documents and xref/object streams are in use
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*
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* @var boolean
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*/
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protected $_readPlain = true;
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/**
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* The current read object
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*
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* @var array
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*/
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protected $_currentObj;
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/**
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* Constructor
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*
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* @param string $filename Source filename
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* @throws InvalidArgumentException
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*/
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public function __construct($filename)
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{
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$this->filename = $filename;
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$this->_f = @fopen($this->filename, 'rb');
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if (!$this->_f) {
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throw new InvalidArgumentException(sprintf('Cannot open %s !', $filename));
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}
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$this->getPdfVersion();
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if (!class_exists('pdf_context')) {
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require_once('pdf_context.php');
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}
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$this->_c = new pdf_context($this->_f);
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// Read xref-Data
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$this->_xref = array();
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$this->_readXref($this->_xref, $this->_findXref());
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// Check for Encryption
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$this->getEncryption();
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// Read root
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$this->_readRoot();
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}
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/**
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* Destructor
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*/
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public function __destruct()
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{
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$this->closeFile();
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}
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/**
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* Close the opened file
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*/
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public function closeFile()
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{
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if (isset($this->_f) && is_resource($this->_f)) {
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fclose($this->_f);
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unset($this->_f);
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}
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}
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/**
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* Check Trailer for Encryption
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*
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* @throws Exception
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*/
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public function getEncryption()
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{
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if (isset($this->_xref['trailer'][1]['/Encrypt'])) {
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throw new Exception('File is encrypted!');
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}
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}
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/**
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* Get PDF-Version
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*
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* @return string
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*/
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public function getPdfVersion()
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{
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if ($this->_pdfVersion === null) {
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fseek($this->_f, 0);
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preg_match('/\d\.\d/', fread($this->_f, 16), $m);
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if (isset($m[0]))
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$this->_pdfVersion = $m[0];
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}
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return $this->_pdfVersion;
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}
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/**
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* Read the /Root dictionary
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*/
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protected function _readRoot()
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{
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if ($this->_xref['trailer'][1]['/Root'][0] != self::TYPE_OBJREF) {
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throw new Exception('Wrong Type of Root-Element! Must be an indirect reference');
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}
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$this->_root = $this->resolveObject($this->_xref['trailer'][1]['/Root']);
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}
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/**
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* Find the xref table
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*
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* @return integer
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* @throws Exception
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*/
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protected function _findXref()
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{
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$toRead = self::$searchForStartxrefLength;
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$stat = fseek($this->_f, -$toRead, SEEK_END);
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if ($stat === -1) {
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fseek($this->_f, 0);
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}
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$data = fread($this->_f, $toRead);
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$keywordPos = strpos(strrev($data), strrev('startxref'));
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if (false === $keywordPos) {
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$keywordPos = strpos(strrev($data), strrev('startref'));
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}
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if (false === $keywordPos) {
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throw new Exception('Unable to find "startxref" keyword.');
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}
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$pos = strlen($data) - $keywordPos;
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$data = substr($data, $pos);
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if (!preg_match('/\s*(\d+).*$/s', $data, $matches)) {
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throw new Exception('Unable to find pointer to xref table.');
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}
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return (int) $matches[1];
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}
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/**
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* Read the xref table
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*
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* @param array $result Array of xref table entries
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* @param integer $offset of xref table
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* @return boolean
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* @throws Exception
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*/
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protected function _readXref(&$result, $offset)
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{
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$tempPos = $offset - min(20, $offset);
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fseek($this->_f, $tempPos); // set some bytes backwards to fetch corrupted docs
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$data = fread($this->_f, 100);
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$xrefPos = strrpos($data, 'xref');
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if ($xrefPos === false) {
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$this->_c->reset($offset);
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$xrefStreamObjDec = $this->_readValue($this->_c);
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if (is_array($xrefStreamObjDec) && isset($xrefStreamObjDec[0]) && $xrefStreamObjDec[0] == self::TYPE_OBJDEC) {
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throw new Exception(
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sprintf(
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'This document (%s) probably uses a compression technique which is not supported by the ' .
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'free parser shipped with FPDI. (See https://www.setasign.com/fpdi-pdf-parser for more details)',
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$this->filename
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)
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);
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} else {
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throw new Exception('Unable to find xref table.');
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}
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}
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if (!isset($result['xrefLocation'])) {
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$result['xrefLocation'] = $tempPos + $xrefPos;
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$result['maxObject'] = 0;
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}
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$cycles = -1;
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$bytesPerCycle = 100;
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fseek($this->_f, $tempPos = $tempPos + $xrefPos + 4); // set the handle directly after the "xref"-keyword
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$data = fread($this->_f, $bytesPerCycle);
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while (($trailerPos = strpos($data, 'trailer', max($bytesPerCycle * $cycles++, 0))) === false && !feof($this->_f)) {
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$data .= fread($this->_f, $bytesPerCycle);
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}
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if ($trailerPos === false) {
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throw new Exception('Trailer keyword not found after xref table');
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}
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$data = ltrim(substr($data, 0, $trailerPos));
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// get Line-Ending
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$found = preg_match_all("/(\r\n|\n|\r)/", substr($data, 0, 100), $m); // check the first 100 bytes for line breaks
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if ($found === 0) {
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throw new Exception('Xref table seems to be corrupted.');
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}
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$differentLineEndings = count(array_unique($m[0]));
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if ($differentLineEndings > 1) {
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$lines = preg_split("/(\r\n|\n|\r)/", $data, -1, PREG_SPLIT_NO_EMPTY);
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} else {
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$lines = explode($m[0][0], $data);
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}
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$data = $differentLineEndings = $m = null;
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unset($data, $differentLineEndings, $m);
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$linesCount = count($lines);
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$start = 1;
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for ($i = 0; $i < $linesCount; $i++) {
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$line = trim($lines[$i]);
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if ($line) {
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$pieces = explode(' ', $line);
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$c = count($pieces);
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switch($c) {
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case 2:
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$start = (int)$pieces[0];
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$end = $start + (int)$pieces[1];
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if ($end > $result['maxObject'])
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$result['maxObject'] = $end;
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break;
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case 3:
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if (!isset($result['xref'][$start]))
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$result['xref'][$start] = array();
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if (!array_key_exists($gen = (int) $pieces[1], $result['xref'][$start])) {
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$result['xref'][$start][$gen] = $pieces[2] == 'n' ? (int) $pieces[0] : null;
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}
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$start++;
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break;
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default:
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throw new Exception('Unexpected data in xref table');
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}
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}
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}
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$lines = $pieces = $line = $start = $end = $gen = null;
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unset($lines, $pieces, $line, $start, $end, $gen);
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$this->_c->reset($tempPos + $trailerPos + 7);
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$trailer = $this->_readValue($this->_c);
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if (!isset($result['trailer'])) {
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$result['trailer'] = $trailer;
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}
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if (isset($trailer[1]['/Prev'])) {
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$this->_readXref($result, $trailer[1]['/Prev'][1]);
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}
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$trailer = null;
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unset($trailer);
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return true;
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}
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/**
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* Reads a PDF value
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*
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* @param pdf_context $c
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* @param string $token A token
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* @return mixed
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* @throws Exception
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*/
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protected function _readValue(&$c, $token = null)
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{
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|
if (is_null($token)) {
|
||
|
|
$token = $this->_readToken($c);
|
||
|
|
}
|
||
|
|
|
||
|
|
if ($token === false) {
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
|
||
|
|
switch ($token) {
|
||
|
|
case '<':
|
||
|
|
// This is a hex string.
|
||
|
|
// Read the value, then the terminator
|
||
|
|
|
||
|
|
$pos = $c->offset;
|
||
|
|
|
||
|
|
while(1) {
|
||
|
|
|
||
|
|
$match = strpos($c->buffer, '>', $pos);
|
||
|
|
|
||
|
|
// If you can't find it, try
|
||
|
|
// reading more data from the stream
|
||
|
|
|
||
|
|
if ($match === false) {
|
||
|
|
if (!$c->increaseLength()) {
|
||
|
|
return false;
|
||
|
|
} else {
|
||
|
|
continue;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
$result = substr($c->buffer, $c->offset, $match - $c->offset);
|
||
|
|
$c->offset = $match + 1;
|
||
|
|
|
||
|
|
return array (self::TYPE_HEX, $result);
|
||
|
|
}
|
||
|
|
break;
|
||
|
|
|
||
|
|
case '<<':
|
||
|
|
// This is a dictionary.
|
||
|
|
|
||
|
|
$result = array();
|
||
|
|
|
||
|
|
// Recurse into this function until we reach
|
||
|
|
// the end of the dictionary.
|
||
|
|
while (($key = $this->_readToken($c)) !== '>>') {
|
||
|
|
if ($key === false) {
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (($value = $this->_readValue($c)) === false) {
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
|
||
|
|
// Catch missing value
|
||
|
|
if ($value[0] == self::TYPE_TOKEN && $value[1] == '>>') {
|
||
|
|
$result[$key] = array(self::TYPE_NULL);
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
|
||
|
|
$result[$key] = $value;
|
||
|
|
}
|
||
|
|
|
||
|
|
return array (self::TYPE_DICTIONARY, $result);
|
||
|
|
|
||
|
|
case '[':
|
||
|
|
// This is an array.
|
||
|
|
|
||
|
|
$result = array();
|
||
|
|
|
||
|
|
// Recurse into this function until we reach
|
||
|
|
// the end of the array.
|
||
|
|
while (($token = $this->_readToken($c)) !== ']') {
|
||
|
|
if ($token === false) {
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
|
||
|
|
if (($value = $this->_readValue($c, $token)) === false) {
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
|
||
|
|
$result[] = $value;
|
||
|
|
}
|
||
|
|
|
||
|
|
return array (self::TYPE_ARRAY, $result);
|
||
|
|
|
||
|
|
case '(':
|
||
|
|
// This is a string
|
||
|
|
$pos = $c->offset;
|
||
|
|
|
||
|
|
$openBrackets = 1;
|
||
|
|
do {
|
||
|
|
for (; $openBrackets != 0 && $pos < $c->length; $pos++) {
|
||
|
|
switch (ord($c->buffer[$pos])) {
|
||
|
|
case 0x28: // '('
|
||
|
|
$openBrackets++;
|
||
|
|
break;
|
||
|
|
case 0x29: // ')'
|
||
|
|
$openBrackets--;
|
||
|
|
break;
|
||
|
|
case 0x5C: // backslash
|
||
|
|
$pos++;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
} while($openBrackets != 0 && $c->increaseLength());
|
||
|
|
|
||
|
|
$result = substr($c->buffer, $c->offset, $pos - $c->offset - 1);
|
||
|
|
$c->offset = $pos;
|
||
|
|
|
||
|
|
return array (self::TYPE_STRING, $result);
|
||
|
|
|
||
|
|
case 'stream':
|
||
|
|
$tempPos = $c->getPos() - strlen($c->buffer);
|
||
|
|
$tempOffset = $c->offset;
|
||
|
|
|
||
|
|
$c->reset($startPos = $tempPos + $tempOffset);
|
||
|
|
|
||
|
|
// Find the first "newline"
|
||
|
|
while ($c->buffer[0] !== chr(10) && $c->buffer[0] !== chr(13)) {
|
||
|
|
$c->reset(++$startPos);
|
||
|
|
if ($c->ensureContent() === false) {
|
||
|
|
throw new Exception(
|
||
|
|
'Unable to parse stream data. No newline followed the stream keyword.'
|
||
|
|
);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
$e = 0; // ensure line breaks in front of the stream
|
||
|
|
if ($c->buffer[0] == chr(10) || $c->buffer[0] == chr(13))
|
||
|
|
$e++;
|
||
|
|
if ($c->buffer[1] == chr(10) && $c->buffer[0] != chr(10))
|
||
|
|
$e++;
|
||
|
|
|
||
|
|
if ($this->_currentObj[1][1]['/Length'][0] == self::TYPE_OBJREF) {
|
||
|
|
$tmpLength = $this->resolveObject($this->_currentObj[1][1]['/Length']);
|
||
|
|
$length = $tmpLength[1][1];
|
||
|
|
} else {
|
||
|
|
$length = $this->_currentObj[1][1]['/Length'][1];
|
||
|
|
}
|
||
|
|
|
||
|
|
if ($length > 0) {
|
||
|
|
$c->reset($startPos + $e, $length);
|
||
|
|
$v = $c->buffer;
|
||
|
|
} else {
|
||
|
|
$v = '';
|
||
|
|
}
|
||
|
|
|
||
|
|
$c->reset($startPos + $e + $length);
|
||
|
|
$endstream = $this->_readToken($c);
|
||
|
|
|
||
|
|
if ($endstream != 'endstream') {
|
||
|
|
$c->reset($startPos + $e + $length + 9); // 9 = strlen("endstream")
|
||
|
|
// We don't throw an error here because the next
|
||
|
|
// round trip will start at a new offset
|
||
|
|
}
|
||
|
|
|
||
|
|
return array(self::TYPE_STREAM, $v);
|
||
|
|
|
||
|
|
default:
|
||
|
|
if (is_numeric($token)) {
|
||
|
|
// A numeric token. Make sure that
|
||
|
|
// it is not part of something else.
|
||
|
|
if (($tok2 = $this->_readToken($c)) !== false) {
|
||
|
|
if (is_numeric($tok2)) {
|
||
|
|
|
||
|
|
// Two numeric tokens in a row.
|
||
|
|
// In this case, we're probably in
|
||
|
|
// front of either an object reference
|
||
|
|
// or an object specification.
|
||
|
|
// Determine the case and return the data
|
||
|
|
if (($tok3 = $this->_readToken($c)) !== false) {
|
||
|
|
switch ($tok3) {
|
||
|
|
case 'obj':
|
||
|
|
return array(self::TYPE_OBJDEC, (int)$token, (int)$tok2);
|
||
|
|
case 'R':
|
||
|
|
return array(self::TYPE_OBJREF, (int)$token, (int)$tok2);
|
||
|
|
}
|
||
|
|
// If we get to this point, that numeric value up
|
||
|
|
// there was just a numeric value. Push the extra
|
||
|
|
// tokens back into the stack and return the value.
|
||
|
|
array_push($c->stack, $tok3);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
array_push($c->stack, $tok2);
|
||
|
|
}
|
||
|
|
|
||
|
|
if ($token === (string)((int)$token))
|
||
|
|
return array(self::TYPE_NUMERIC, (int)$token);
|
||
|
|
else
|
||
|
|
return array(self::TYPE_REAL, (float)$token);
|
||
|
|
} else if ($token == 'true' || $token == 'false') {
|
||
|
|
return array(self::TYPE_BOOLEAN, $token == 'true');
|
||
|
|
} else if ($token == 'null') {
|
||
|
|
return array(self::TYPE_NULL);
|
||
|
|
} else {
|
||
|
|
// Just a token. Return it.
|
||
|
|
return array(self::TYPE_TOKEN, $token);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Resolve an object
|
||
|
|
*
|
||
|
|
* @param array $objSpec The object-data
|
||
|
|
* @return array|boolean
|
||
|
|
* @throws Exception
|
||
|
|
*/
|
||
|
|
public function resolveObject($objSpec)
|
||
|
|
{
|
||
|
|
$c = $this->_c;
|
||
|
|
|
||
|
|
// Exit if we get invalid data
|
||
|
|
if (!is_array($objSpec)) {
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
|
||
|
|
if ($objSpec[0] == self::TYPE_OBJREF) {
|
||
|
|
|
||
|
|
// This is a reference, resolve it
|
||
|
|
if (isset($this->_xref['xref'][$objSpec[1]][$objSpec[2]])) {
|
||
|
|
|
||
|
|
// Save current file position
|
||
|
|
// This is needed if you want to resolve
|
||
|
|
// references while you're reading another object
|
||
|
|
// (e.g.: if you need to determine the length
|
||
|
|
// of a stream)
|
||
|
|
|
||
|
|
$oldPos = $c->getPos();
|
||
|
|
|
||
|
|
// Reposition the file pointer and
|
||
|
|
// load the object header.
|
||
|
|
|
||
|
|
$c->reset($this->_xref['xref'][$objSpec[1]][$objSpec[2]]);
|
||
|
|
|
||
|
|
$header = $this->_readValue($c);
|
||
|
|
|
||
|
|
if ($header[0] != self::TYPE_OBJDEC || $header[1] != $objSpec[1] || $header[2] != $objSpec[2]) {
|
||
|
|
$toSearchFor = $objSpec[1] . ' ' . $objSpec[2] . ' obj';
|
||
|
|
if (preg_match('/' . $toSearchFor . '/', $c->buffer)) {
|
||
|
|
$c->offset = strpos($c->buffer, $toSearchFor) + strlen($toSearchFor);
|
||
|
|
// reset stack
|
||
|
|
$c->stack = array();
|
||
|
|
} else {
|
||
|
|
throw new Exception(
|
||
|
|
sprintf("Unable to find object (%s, %s) at expected location.", $objSpec[1], $objSpec[2])
|
||
|
|
);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
// If we're being asked to store all the information
|
||
|
|
// about the object, we add the object ID and generation
|
||
|
|
// number for later use
|
||
|
|
$result = array (
|
||
|
|
self::TYPE_OBJECT,
|
||
|
|
'obj' => $objSpec[1],
|
||
|
|
'gen' => $objSpec[2]
|
||
|
|
);
|
||
|
|
|
||
|
|
$this->_currentObj =& $result;
|
||
|
|
|
||
|
|
// Now simply read the object data until
|
||
|
|
// we encounter an end-of-object marker
|
||
|
|
while (true) {
|
||
|
|
$value = $this->_readValue($c);
|
||
|
|
if ($value === false || count($result) > 4) {
|
||
|
|
// in this case the parser couldn't find an "endobj" so we break here
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
|
||
|
|
if ($value[0] == self::TYPE_TOKEN && $value[1] === 'endobj') {
|
||
|
|
break;
|
||
|
|
}
|
||
|
|
|
||
|
|
$result[] = $value;
|
||
|
|
}
|
||
|
|
|
||
|
|
$c->reset($oldPos);
|
||
|
|
|
||
|
|
if (isset($result[2][0]) && $result[2][0] == self::TYPE_STREAM) {
|
||
|
|
$result[0] = self::TYPE_STREAM;
|
||
|
|
}
|
||
|
|
|
||
|
|
} else {
|
||
|
|
throw new Exception(
|
||
|
|
sprintf("Unable to find object (%s, %s) at expected location.", $objSpec[1], $objSpec[2])
|
||
|
|
);
|
||
|
|
}
|
||
|
|
|
||
|
|
return $result;
|
||
|
|
} else {
|
||
|
|
return $objSpec;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Reads a token from the context
|
||
|
|
*
|
||
|
|
* @param pdf_context $c
|
||
|
|
* @return mixed
|
||
|
|
*/
|
||
|
|
protected function _readToken($c)
|
||
|
|
{
|
||
|
|
// If there is a token available
|
||
|
|
// on the stack, pop it out and
|
||
|
|
// return it.
|
||
|
|
|
||
|
|
if (count($c->stack)) {
|
||
|
|
return array_pop($c->stack);
|
||
|
|
}
|
||
|
|
|
||
|
|
// Strip away any whitespace
|
||
|
|
|
||
|
|
do {
|
||
|
|
if (!$c->ensureContent()) {
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
$c->offset += strspn($c->buffer, "\x20\x0A\x0C\x0D\x09\x00", $c->offset);
|
||
|
|
} while ($c->offset >= $c->length - 1);
|
||
|
|
|
||
|
|
// Get the first character in the stream
|
||
|
|
|
||
|
|
$char = $c->buffer[$c->offset++];
|
||
|
|
|
||
|
|
switch ($char) {
|
||
|
|
|
||
|
|
case '[':
|
||
|
|
case ']':
|
||
|
|
case '(':
|
||
|
|
case ')':
|
||
|
|
|
||
|
|
// This is either an array or literal string
|
||
|
|
// delimiter, Return it
|
||
|
|
|
||
|
|
return $char;
|
||
|
|
|
||
|
|
case '<':
|
||
|
|
case '>':
|
||
|
|
|
||
|
|
// This could either be a hex string or
|
||
|
|
// dictionary delimiter. Determine the
|
||
|
|
// appropriate case and return the token
|
||
|
|
|
||
|
|
if ($c->buffer[$c->offset] == $char) {
|
||
|
|
if (!$c->ensureContent()) {
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
$c->offset++;
|
||
|
|
return $char . $char;
|
||
|
|
} else {
|
||
|
|
return $char;
|
||
|
|
}
|
||
|
|
|
||
|
|
case '%':
|
||
|
|
|
||
|
|
// This is a comment - jump over it!
|
||
|
|
|
||
|
|
$pos = $c->offset;
|
||
|
|
while(1) {
|
||
|
|
$match = preg_match("/(\r\n|\r|\n)/", $c->buffer, $m, PREG_OFFSET_CAPTURE, $pos);
|
||
|
|
if ($match === 0) {
|
||
|
|
if (!$c->increaseLength()) {
|
||
|
|
return false;
|
||
|
|
} else {
|
||
|
|
continue;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
$c->offset = $m[0][1] + strlen($m[0][0]);
|
||
|
|
|
||
|
|
return $this->_readToken($c);
|
||
|
|
}
|
||
|
|
|
||
|
|
default:
|
||
|
|
|
||
|
|
// This is "another" type of token (probably
|
||
|
|
// a dictionary entry or a numeric value)
|
||
|
|
// Find the end and return it.
|
||
|
|
|
||
|
|
if (!$c->ensureContent()) {
|
||
|
|
return false;
|
||
|
|
}
|
||
|
|
|
||
|
|
while(1) {
|
||
|
|
|
||
|
|
// Determine the length of the token
|
||
|
|
|
||
|
|
$pos = strcspn($c->buffer, "\x20%[]<>()/\x0A\x0C\x0D\x09\x00", $c->offset);
|
||
|
|
|
||
|
|
if ($c->offset + $pos <= $c->length - 1) {
|
||
|
|
break;
|
||
|
|
} else {
|
||
|
|
// If the script reaches this point,
|
||
|
|
// the token may span beyond the end
|
||
|
|
// of the current buffer. Therefore,
|
||
|
|
// we increase the size of the buffer
|
||
|
|
// and try again--just to be safe.
|
||
|
|
|
||
|
|
$c->increaseLength();
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
$result = substr($c->buffer, $c->offset - 1, $pos + 1);
|
||
|
|
|
||
|
|
$c->offset += $pos;
|
||
|
|
|
||
|
|
return $result;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
/**
|
||
|
|
* Un-filter a stream object
|
||
|
|
*
|
||
|
|
* @param array $obj
|
||
|
|
* @return string
|
||
|
|
* @throws Exception
|
||
|
|
*/
|
||
|
|
protected function _unFilterStream($obj)
|
||
|
|
{
|
||
|
|
$filters = array();
|
||
|
|
|
||
|
|
if (isset($obj[1][1]['/Filter'])) {
|
||
|
|
$filter = $obj[1][1]['/Filter'];
|
||
|
|
|
||
|
|
if ($filter[0] == pdf_parser::TYPE_OBJREF) {
|
||
|
|
$tmpFilter = $this->resolveObject($filter);
|
||
|
|
$filter = $tmpFilter[1];
|
||
|
|
}
|
||
|
|
|
||
|
|
if ($filter[0] == pdf_parser::TYPE_TOKEN) {
|
||
|
|
$filters[] = $filter;
|
||
|
|
} else if ($filter[0] == pdf_parser::TYPE_ARRAY) {
|
||
|
|
$filters = $filter[1];
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
$stream = $obj[2][1];
|
||
|
|
|
||
|
|
foreach ($filters AS $filter) {
|
||
|
|
switch ($filter[1]) {
|
||
|
|
case '/FlateDecode':
|
||
|
|
case '/Fl':
|
||
|
|
if (function_exists('gzuncompress')) {
|
||
|
|
$oStream = $stream;
|
||
|
|
$stream = (strlen($stream) > 0) ? @gzuncompress($stream) : '';
|
||
|
|
} else {
|
||
|
|
throw new Exception(
|
||
|
|
sprintf('To handle %s filter, please compile php with zlib support.', $filter[1])
|
||
|
|
);
|
||
|
|
}
|
||
|
|
|
||
|
|
if ($stream === false) {
|
||
|
|
$tries = 0;
|
||
|
|
while ($tries < 8 && ($stream === false || strlen($stream) < strlen($oStream))) {
|
||
|
|
$oStream = substr($oStream, 1);
|
||
|
|
$stream = @gzinflate($oStream);
|
||
|
|
$tries++;
|
||
|
|
}
|
||
|
|
|
||
|
|
if ($stream === false) {
|
||
|
|
throw new Exception('Error while decompressing stream.');
|
||
|
|
}
|
||
|
|
}
|
||
|
|
break;
|
||
|
|
case '/LZWDecode':
|
||
|
|
if (!class_exists('FilterLZW')) {
|
||
|
|
require_once('filters/FilterLZW.php');
|
||
|
|
}
|
||
|
|
$decoder = new FilterLZW();
|
||
|
|
$stream = $decoder->decode($stream);
|
||
|
|
break;
|
||
|
|
case '/ASCII85Decode':
|
||
|
|
if (!class_exists('FilterASCII85')) {
|
||
|
|
require_once('filters/FilterASCII85.php');
|
||
|
|
}
|
||
|
|
$decoder = new FilterASCII85();
|
||
|
|
$stream = $decoder->decode($stream);
|
||
|
|
break;
|
||
|
|
case '/ASCIIHexDecode':
|
||
|
|
if (!class_exists('FilterASCIIHexDecode')) {
|
||
|
|
require_once('filters/FilterASCIIHexDecode.php');
|
||
|
|
}
|
||
|
|
$decoder = new FilterASCIIHexDecode();
|
||
|
|
$stream = $decoder->decode($stream);
|
||
|
|
break;
|
||
|
|
case null:
|
||
|
|
break;
|
||
|
|
default:
|
||
|
|
throw new Exception(sprintf('Unsupported Filter: %s', $filter[1]));
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
return $stream;
|
||
|
|
}
|
||
|
|
}
|