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<?php//============================================================+// File name : tcpdf_parser.php// Version : 1.0.003// Begin : 2011-05-23// Last Update : 2013-03-17// Author : Nicola Asuni - Tecnick.com LTD - www.tecnick.com - info@tecnick.com// License : GNU-LGPL v3 (http://www.gnu.org/copyleft/lesser.html)// -------------------------------------------------------------------// Copyright (C) 2011-2013 Nicola Asuni - Tecnick.com LTD//// This file is part of TCPDF software library.//// TCPDF is free software: you can redistribute it and/or modify it// under the terms of the GNU Lesser General Public License as// published by the Free Software Foundation, either version 3 of the// License, or (at your option) any later version.//// TCPDF 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 Lesser General Public License for more details.//// You should have received a copy of the License// along with TCPDF. If not, see// <http://www.tecnick.com/pagefiles/tcpdf/LICENSE.TXT>.//// See LICENSE.TXT file for more information.// -------------------------------------------------------------------//// Description : This is a PHP class for parsing PDF documents.////============================================================+/*** @file* This is a PHP class for parsing PDF documents.<br>* @package com.tecnick.tcpdf* @author Nicola Asuni* @version 1.0.003*/// include class for decoding filtersrequire_once(dirname(__FILE__).'/include/tcpdf_filters.php');/*** @class TCPDF_PARSER* This is a PHP class for parsing PDF documents.<br>* @package com.tecnick.tcpdf* @brief This is a PHP class for parsing PDF documents..* @version 1.0.003* @author Nicola Asuni - info@tecnick.com*/class TCPDF_PARSER {/*** Raw content of the PDF document.* @private*/private $pdfdata = '';/*** XREF data.* @protected*/protected $xref = array();/*** Array of PDF objects.* @protected*/protected $objects = array();/*** Class object for decoding filters.* @private*/private $FilterDecoders;// -----------------------------------------------------------------------------/*** Parse a PDF document an return an array of objects.* @param $data (string) PDF data to parse.* @public* @since 1.0.000 (2011-05-24)*/public function __construct($data) {if (empty($data)) {$this->Error('Empty PDF data.');}$this->pdfdata = $data;// get length$pdflen = strlen($this->pdfdata);// initialize class for decoding filters$this->FilterDecoders = new TCPDF_FILTERS();// get xref and trailer data$this->xref = $this->getXrefData();// parse all document objects$this->objects = array();foreach ($this->xref['xref'] as $obj => $offset) {if (!isset($this->objects[$obj]) AND ($offset > 0)) {// decode only objects with positive offset$this->objects[$obj] = $this->getIndirectObject($obj, $offset, true);}}// release some memoryunset($this->pdfdata);$this->pdfdata = '';}/*** Return an array of parsed PDF document objects.* @return (array) Array of parsed PDF document objects.* @public* @since 1.0.000 (2011-06-26)*/public function getParsedData() {return array($this->xref, $this->objects);}/*** Get Cross-Reference (xref) table and trailer data from PDF document data.* @param $offset (int) xref offset (if know).* @param $xref (array) previous xref array (if any).* @return Array containing xref and trailer data.* @protected* @since 1.0.000 (2011-05-24)*/protected function getXrefData($offset=0, $xref=array()) {if ($offset == 0) {// find last startxrefif (preg_match_all('/[\r\n]startxref[\s]*[\r\n]+([0-9]+)[\s]*[\r\n]+%%EOF/i', $this->pdfdata, $matches, PREG_SET_ORDER, $offset) == 0) {$this->Error('Unable to find startxref');}$matches = array_pop($matches);$startxref = $matches[1];} else {if (preg_match('/([0-9]+[\s][0-9]+[\s]obj)/i', $this->pdfdata, $matches, PREG_OFFSET_CAPTURE, $offset)) {// Cross-Reference Stream object$startxref = $offset;} elseif (preg_match('/[\r\n]startxref[\s]*[\r\n]+([0-9]+)[\s]*[\r\n]+%%EOF/i', $this->pdfdata, $matches, PREG_OFFSET_CAPTURE, $offset)) {// startxref found$startxref = $matches[1][0];} else {$this->Error('Unable to find startxref');}}// check xref positionif (strpos($this->pdfdata, 'xref', $startxref) == $startxref) {// Cross-Reference$xref = $this->decodeXref($startxref, $xref);} else {// Cross-Reference Stream$xref = $this->decodeXrefStream($startxref, $xref);}if (empty($xref)) {$this->Error('Unable to find xref');}return $xref;}/*** Decode the Cross-Reference section* @param $startxref (int) Offset at which the xref section starts.* @param $xref (array) Previous xref array (if any).* @return Array containing xref and trailer data.* @protected* @since 1.0.000 (2011-06-20)*/protected function decodeXref($startxref, $xref=array()) {// extract xref data (object indexes and offsets)$xoffset = $startxref + 5;// initialize object number$obj_num = 0;$offset = $xoffset;while (preg_match('/^([0-9]+)[\s]([0-9]+)[\s]?([nf]?)/im', $this->pdfdata, $matches, PREG_OFFSET_CAPTURE, $offset) > 0) {$offset = (strlen($matches[0][0]) + $matches[0][1]);if ($matches[3][0] == 'n') {// create unique object index: [object number]_[generation number]$index = $obj_num.'_'.intval($matches[2][0]);// check if object already existif (!isset($xref['xref'][$index])) {// store object offset position$xref['xref'][$index] = intval($matches[1][0]);}++$obj_num;$offset += 2;} elseif ($matches[3][0] == 'f') {++$obj_num;$offset += 2;} else {// object number (index)$obj_num = intval($matches[1][0]);}}// get trailer dataif (preg_match('/trailer[\s]*<<(.*)>>[\s]*[\r\n]+startxref[\s]*[\r\n]+/isU', $this->pdfdata, $matches, PREG_OFFSET_CAPTURE, $xoffset) > 0) {$trailer_data = $matches[1][0];if (!isset($xref['trailer']) OR empty($xref['trailer'])) {// get only the last updated version$xref['trailer'] = array();// parse trailer_dataif (preg_match('/Size[\s]+([0-9]+)/i', $trailer_data, $matches) > 0) {$xref['trailer']['size'] = intval($matches[1]);}if (preg_match('/Root[\s]+([0-9]+)[\s]+([0-9]+)[\s]+R/i', $trailer_data, $matches) > 0) {$xref['trailer']['root'] = intval($matches[1]).'_'.intval($matches[2]);}if (preg_match('/Encrypt[\s]+([0-9]+)[\s]+([0-9]+)[\s]+R/i', $trailer_data, $matches) > 0) {$xref['trailer']['encrypt'] = intval($matches[1]).'_'.intval($matches[2]);}if (preg_match('/Info[\s]+([0-9]+)[\s]+([0-9]+)[\s]+R/i', $trailer_data, $matches) > 0) {$xref['trailer']['info'] = intval($matches[1]).'_'.intval($matches[2]);}if (preg_match('/ID[\s]*[\[][\s]*[<]([^>]*)[>][\s]*[<]([^>]*)[>]/i', $trailer_data, $matches) > 0) {$xref['trailer']['id'] = array();$xref['trailer']['id'][0] = $matches[1];$xref['trailer']['id'][1] = $matches[2];}}if (preg_match('/Prev[\s]+([0-9]+)/i', $trailer_data, $matches) > 0) {// get previous xref$xref = $this->getXrefData(intval($matches[1]), $xref);}} else {$this->Error('Unable to find trailer');}return $xref;}/*** Decode the Cross-Reference Stream section* @param $startxref (int) Offset at which the xref section starts.* @param $xref (array) Previous xref array (if any).* @return Array containing xref and trailer data.* @protected* @since 1.0.003 (2013-03-16)*/protected function decodeXrefStream($startxref, $xref=array()) {// try to read Cross-Reference Stream$xrefobj = $this->getRawObject($startxref);$xrefcrs = $this->getIndirectObject($xrefobj[1], $startxref, true);if (!isset($xref['trailer']) OR empty($xref['trailer'])) {// get only the last updated version$xref['trailer'] = array();$filltrailer = true;} else {$filltrailer = false;}$valid_crs = false;$sarr = $xrefcrs[0][1];foreach ($sarr as $k => $v) {if (($v[0] == '/') AND ($v[1] == 'Type') AND (isset($sarr[($k +1)]) AND ($sarr[($k +1)][0] == '/') AND ($sarr[($k +1)][1] == 'XRef'))) {$valid_crs = true;} elseif (($v[0] == '/') AND ($v[1] == 'Index') AND (isset($sarr[($k +1)]))) {// first object number in the subsection$index_first = intval($sarr[($k +1)][1][0][1]);// number of entries in the subsection$index_entries = intval($sarr[($k +1)][1][1][1]);} elseif (($v[0] == '/') AND ($v[1] == 'Prev') AND (isset($sarr[($k +1)]) AND ($sarr[($k +1)][0] == 'numeric'))) {// get previous xref offset$prevxref = intval($sarr[($k +1)][1]);} elseif (($v[0] == '/') AND ($v[1] == 'W') AND (isset($sarr[($k +1)]))) {// number of bytes (in the decoded stream) of the corresponding field$wb = array();$wb[0] = intval($sarr[($k +1)][1][0][1]);$wb[1] = intval($sarr[($k +1)][1][1][1]);$wb[2] = intval($sarr[($k +1)][1][2][1]);} elseif (($v[0] == '/') AND ($v[1] == 'DecodeParms') AND (isset($sarr[($k +1)][1]))) {$decpar = $sarr[($k +1)][1];foreach ($decpar as $kdc => $vdc) {if (($vdc[0] == '/') AND ($vdc[1] == 'Columns') AND (isset($decpar[($kdc +1)]) AND ($decpar[($kdc +1)][0] == 'numeric'))) {$columns = intval($decpar[($kdc +1)][1]);} elseif (($vdc[0] == '/') AND ($vdc[1] == 'Predictor') AND (isset($decpar[($kdc +1)]) AND ($decpar[($kdc +1)][0] == 'numeric'))) {$predictor = intval($decpar[($kdc +1)][1]);}}} elseif ($filltrailer) {if (($v[0] == '/') AND ($v[1] == 'Size') AND (isset($sarr[($k +1)]) AND ($sarr[($k +1)][0] == 'numeric'))) {$xref['trailer']['size'] = $sarr[($k +1)][1];} elseif (($v[0] == '/') AND ($v[1] == 'Root') AND (isset($sarr[($k +1)]) AND ($sarr[($k +1)][0] == 'ojbref'))) {$xref['trailer']['root'] = $sarr[($k +1)][1];} elseif (($v[0] == '/') AND ($v[1] == 'Info') AND (isset($sarr[($k +1)]) AND ($sarr[($k +1)][0] == 'ojbref'))) {$xref['trailer']['info'] = $sarr[($k +1)][1];} elseif (($v[0] == '/') AND ($v[1] == 'ID') AND (isset($sarr[($k +1)]))) {$xref['trailer']['id'] = array();$xref['trailer']['id'][0] = $sarr[($k +1)][1][0][1];$xref['trailer']['id'][1] = $sarr[($k +1)][1][1][1];}}}// decode dataif ($valid_crs AND isset($xrefcrs[1][3][0])) {// number of bytes in a row$rowlen = ($columns + 1);// convert the stream into an array of integers$sdata = unpack('C*', $xrefcrs[1][3][0]);// split the rows$sdata = array_chunk($sdata, $rowlen);// initialize decoded array$ddata = array();// initialize first row with zeros$prev_row = array_fill (0, $rowlen, 0);// for each row apply PNG unpredictorforeach ($sdata as $k => $row) {// initialize new row$ddata[$k] = array();// get PNG predictor value$predictor = (10 + $row[0]);// for each byte on the rowfor ($i=1; $i<=$columns; ++$i) {// new index$j = ($i - 1);$row_up = $prev_row[$j];if ($i == 1) {$row_left = 0;$row_upleft = 0;} else {$row_left = $row[($i - 1)];$row_upleft = $prev_row[($j - 1)];}switch ($predictor) {case 10: { // PNG prediction (on encoding, PNG None on all rows)$ddata[$k][$j] = $row[$i];break;}case 11: { // PNG prediction (on encoding, PNG Sub on all rows)$ddata[$k][$j] = (($row[$i] + $row_left) & 0xff);break;}case 12: { // PNG prediction (on encoding, PNG Up on all rows)$ddata[$k][$j] = (($row[$i] + $row_up) & 0xff);break;}case 13: { // PNG prediction (on encoding, PNG Average on all rows)$ddata[$k][$j] = (($row[$i] + (($row_left + $row_up) / 2)) & 0xff);break;}case 14: { // PNG prediction (on encoding, PNG Paeth on all rows)// initial estimate$p = ($row_left + $row_up - $row_upleft);// distances$pa = abs($p - $row_left);$pb = abs($p - $row_up);$pc = abs($p - $row_upleft);$pmin = min($pa, $pb, $pc);// return minumum distanceswitch ($pmin) {case $pa: {$ddata[$k][$j] = (($row[$i] + $row_left) & 0xff);break;}case $pb: {$ddata[$k][$j] = (($row[$i] + $row_up) & 0xff);break;}case $pc: {$ddata[$k][$j] = (($row[$i] + $row_upleft) & 0xff);break;}}break;}default: { // PNG prediction (on encoding, PNG optimum)$this->Error('Unknown PNG predictor');break;}}}$prev_row = $ddata[$k];} // end for each row// complete decoding$sdata = array();// for every rowforeach ($ddata as $k => $row) {// initialize new row$sdata[$k] = array(0, 0, 0);if ($wb[0] == 0) {// default type field$sdata[$k][0] = 1;}$i = 0; // count bytes on the row// for every columnfor ($c = 0; $c < 3; ++$c) {// for every byte on the columnfor ($b = 0; $b < $wb[$c]; ++$b) {$sdata[$k][$c] += ($row[$i] << (($wb[$c] - 1 - $b) * 8));++$i;}}}$ddata = array();// fill xrefif (isset($index_first)) {$obj_num = $index_first;} else {$obj_num = 0;}foreach ($sdata as $k => $row) {switch ($row[0]) {case 0: { // (f) linked list of free objects++$obj_num;break;}case 1: { // (n) objects that are in use but are not compressed// create unique object index: [object number]_[generation number]$index = $obj_num.'_'.$row[2];// check if object already existif (!isset($xref['xref'][$index])) {// store object offset position$xref['xref'][$index] = $row[1];}++$obj_num;break;}case 2: { // compressed objects// $row[1] = object number of the object stream in which this object is stored// $row[2] = index of this object within the object stream$index = $row[1].'_0_'.$row[2];$xref['xref'][$index] = -1;break;}default: { // null objectsbreak;}}}} // end decoding dataif (isset($prevxref)) {// get previous xref$xref = $this->getXrefData($prevxref, $xref);}return $xref;}/*** Get object type, raw value and offset to next object* @param $offset (int) Object offset.* @return array containing object type, raw value and offset to next object* @protected* @since 1.0.000 (2011-06-20)*/protected function getRawObject($offset=0) {$objtype = ''; // object type to be returned$objval = ''; // object value to be returned// skip initial white space chars: \x00 null (NUL), \x09 horizontal tab (HT), \x0A line feed (LF), \x0C form feed (FF), \x0D carriage return (CR), \x20 space (SP)$offset += strspn($this->pdfdata, "\x00\x09\x0a\x0c\x0d\x20", $offset);// get first char$char = $this->pdfdata{$offset};// get object typeswitch ($char) {case '%': { // \x25 PERCENT SIGN// skip comment and search for next token$next = strcspn($this->pdfdata, "\r\n", $offset);if ($next > 0) {$offset += $next;return $this->getRawObject($this->pdfdata, $offset);}break;}case '/': { // \x2F SOLIDUS// name object$objtype = $char;++$offset;if (preg_match('/^([^\x00\x09\x0a\x0c\x0d\x20\s\x28\x29\x3c\x3e\x5b\x5d\x7b\x7d\x2f\x25]+)/', substr($this->pdfdata, $offset, 256), $matches) == 1) {$objval = $matches[1]; // unescaped value$offset += strlen($objval);}break;}case '(': // \x28 LEFT PARENTHESIScase ')': { // \x29 RIGHT PARENTHESIS// literal string object$objtype = $char;++$offset;$strpos = $offset;if ($char == '(') {$open_bracket = 1;while ($open_bracket > 0) {if (!isset($this->pdfdata{$strpos})) {break;}$ch = $this->pdfdata{$strpos};switch ($ch) {case '\\': { // REVERSE SOLIDUS (5Ch) (Backslash)// skip next character++$strpos;break;}case '(': { // LEFT PARENHESIS (28h)++$open_bracket;break;}case ')': { // RIGHT PARENTHESIS (29h)--$open_bracket;break;}}++$strpos;}$objval = substr($this->pdfdata, $offset, ($strpos - $offset - 1));$offset = $strpos;}break;}case '[': // \x5B LEFT SQUARE BRACKETcase ']': { // \x5D RIGHT SQUARE BRACKET// array object$objtype = $char;++$offset;if ($char == '[') {// get array content$objval = array();do {// get element$element = $this->getRawObject($offset);$offset = $element[2];$objval[] = $element;} while ($element[0] != ']');// remove closing delimiterarray_pop($objval);}break;}case '<': // \x3C LESS-THAN SIGNcase '>': { // \x3E GREATER-THAN SIGNif (isset($this->pdfdata{($offset + 1)}) AND ($this->pdfdata{($offset + 1)} == $char)) {// dictionary object$objtype = $char.$char;$offset += 2;if ($char == '<') {// get array content$objval = array();do {// get element$element = $this->getRawObject($offset);$offset = $element[2];$objval[] = $element;} while ($element[0] != '>>');// remove closing delimiterarray_pop($objval);}} else {// hexadecimal string object$objtype = $char;++$offset;if (($char == '<') AND (preg_match('/^([0-9A-Fa-f]+)[>]/iU', substr($this->pdfdata, $offset), $matches) == 1)) {$objval = $matches[1];$offset += strlen($matches[0]);}}break;}default: {if (substr($this->pdfdata, $offset, 6) == 'endobj') {// indirect object$objtype = 'endobj';$offset += 6;} elseif (substr($this->pdfdata, $offset, 4) == 'null') {// null object$objtype = 'null';$offset += 4;$objval = 'null';} elseif (substr($this->pdfdata, $offset, 4) == 'true') {// boolean true object$objtype = 'boolean';$offset += 4;$objval = 'true';} elseif (substr($this->pdfdata, $offset, 5) == 'false') {// boolean false object$objtype = 'boolean';$offset += 5;$objval = 'false';} elseif (substr($this->pdfdata, $offset, 6) == 'stream') {// start stream object$objtype = 'stream';$offset += 6;if (preg_match('/^([\r\n]+)/isU', substr($this->pdfdata, $offset), $matches) == 1) {$offset += strlen($matches[0]);}if (preg_match('/([\r\n]*endstream)/isU', substr($this->pdfdata, $offset), $matches, PREG_OFFSET_CAPTURE) == 1) {$objval = substr($this->pdfdata, $offset, $matches[0][1]);$offset += $matches[0][1];}} elseif (substr($this->pdfdata, $offset, 9) == 'endstream') {// end stream object$objtype = 'endstream';$offset += 9;} elseif (preg_match('/^([0-9]+)[\s]+([0-9]+)[\s]+R/iU', substr($this->pdfdata, $offset, 33), $matches) == 1) {// indirect object reference$objtype = 'ojbref';$offset += strlen($matches[0]);$objval = intval($matches[1]).'_'.intval($matches[2]);} elseif (preg_match('/^([0-9]+)[\s]+([0-9]+)[\s]+obj/iU', substr($this->pdfdata, $offset, 33), $matches) == 1) {// object start$objtype = 'ojb';$objval = intval($matches[1]).'_'.intval($matches[2]);$offset += strlen ($matches[0]);} elseif (($numlen = strspn($this->pdfdata, '+-.0123456789', $offset)) > 0) {// numeric object$objtype = 'numeric';$objval = substr($this->pdfdata, $offset, $numlen);$offset += $numlen;}break;}}return array($objtype, $objval, $offset);}/*** Get content of indirect object.* @param $obj_ref (string) Object number and generation number separated by underscore character.* @param $offset (int) Object offset.* @param $decoding (boolean) If true decode streams.* @return array containing object data.* @protected* @since 1.0.000 (2011-05-24)*/protected function getIndirectObject($obj_ref, $offset=0, $decoding=true) {$obj = explode('_', $obj_ref);if (($obj === false) OR (count($obj) != 2)) {$this->Error('Invalid object reference: '.$obj);return;}$objref = $obj[0].' '.$obj[1].' obj';if (strpos($this->pdfdata, $objref, $offset) != $offset) {// an indirect reference to an undefined object shall be considered a reference to the null objectreturn array('null', 'null', $offset);}// starting position of object content$offset += strlen($objref);// get array of object content$objdata = array();$i = 0; // object main indexdo {// get element$element = $this->getRawObject($offset);$offset = $element[2];// decode stream using stream's dictionary informationif ($decoding AND ($element[0] == 'stream') AND (isset($objdata[($i - 1)][0])) AND ($objdata[($i - 1)][0] == '<<')) {$element[3] = $this->decodeStream($objdata[($i - 1)][1], substr($element[1], 1));}$objdata[$i] = $element;++$i;} while ($element[0] != 'endobj');// remove closing delimiterarray_pop($objdata);// return raw object contentreturn $objdata;}/*** Get the content of object, resolving indect object reference if necessary.* @param $obj (string) Object value.* @return array containing object data.* @protected* @since 1.0.000 (2011-06-26)*/protected function getObjectVal($obj) {if ($obj[0] == 'objref') {// reference to indirect objectif (isset($this->objects[$obj[1]])) {// this object has been already parsedreturn $this->objects[$obj[1]];} elseif (isset($this->xref[$obj[1]])) {// parse new object$this->objects[$obj[1]] = $this->getIndirectObject($obj[1], $this->xref[$obj[1]], false);return $this->objects[$obj[1]];}}return $obj;}/*** Decode the specified stream.* @param $sdic (array) Stream's dictionary array.* @param $stream (string) Stream to decode.* @return array containing decoded stream data and remaining filters.* @protected* @since 1.0.000 (2011-06-22)*/protected function decodeStream($sdic, $stream) {// get stream lenght and filters$slength = strlen($stream);if ($slength <= 0) {return array('', array());}$filters = array();foreach ($sdic as $k => $v) {if ($v[0] == '/') {if (($v[1] == 'Length') AND (isset($sdic[($k + 1)])) AND ($sdic[($k + 1)][0] == 'numeric')) {// get declared stream lenght$declength = intval($sdic[($k + 1)][1]);if ($declength < $slength) {$stream = substr($stream, 0, $declength);$slength = $declength;}} elseif (($v[1] == 'Filter') AND (isset($sdic[($k + 1)]))) {// resolve indirect object$objval = $this->getObjectVal($sdic[($k + 1)]);if ($objval[0] == '/') {// single filter$filters[] = $objval[1];} elseif ($objval[0] == '[') {// array of filtersforeach ($objval[1] as $flt) {if ($flt[0] == '/') {$filters[] = $flt[1];}}}}}}// decode the stream$remaining_filters = array();foreach ($filters as $filter) {if (in_array($filter, $this->FilterDecoders->getAvailableFilters())) {$stream = $this->FilterDecoders->decodeFilter($filter, $stream);} else {// add missing filter to array$remaining_filters[] = $filter;}}return array($stream, $remaining_filters);}/*** This method is automatically called in case of fatal error; it simply outputs the message and halts the execution.* @param $msg (string) The error message* @public* @since 1.0.000 (2011-05-23)*/public function Error($msg) {// exit program and print errordie('<strong>TCPDF_PARSER ERROR: </strong>'.$msg);}} // END OF TCPDF_PARSER CLASS//============================================================+// END OF FILE//============================================================+