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918 lines
28 KiB
918 lines
28 KiB
/*
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* Copyright (C) 2015-2022 Département de l'Instruction Publique (DIP-SEM)
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*
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* Copyright (C) 2013 Open Education Foundation
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*
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* Copyright (C) 2010-2013 Groupement d'Intérêt Public pour
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* l'Education Numérique en Afrique (GIP ENA)
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*
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* This file is part of OpenBoard.
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*
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* OpenBoard is free software: you can redistribute it and/or modify
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* it under the terms of the GNU General Public License as published by
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* the Free Software Foundation, version 3 of the License,
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* with a specific linking exception for the OpenSSL project's
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* "OpenSSL" library (or with modified versions of it that use the
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* same license as the "OpenSSL" library).
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*
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* OpenBoard is distributed in the hope that it will be useful,
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* but WITHOUT ANY WARRANTY; without even the implied warranty of
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* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
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* GNU General Public License for more details.
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*
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* You should have received a copy of the GNU General Public License
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* along with OpenBoard. If not, see <http://www.gnu.org/licenses/>.
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*/
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#include <QtGlobal>
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#include <fstream>
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#include <iostream>
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#include <vector>
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#include <map>
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#include <stack>
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#include <string.h>
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#include "Parser.h"
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#include "Object.h"
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#include "Exception.h"
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#include "Utils.h"
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#include "core/memcheck.h"
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using namespace merge_lib;
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using namespace std;
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const std::string Parser::WHITESPACES(" \t\f\v\n\r");
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const std::string Parser::DELIMETERS("()<>{}/%][");
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const std::string Parser::NUMBERS("0123456789");
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const std::string Parser::WHITESPACES_AND_DELIMETERS = Parser::WHITESPACES + Parser::DELIMETERS;
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Document * Parser::parseDocument(const char * fileName)
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{
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_document = new Document(fileName);
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try
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{
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_createObjectTree(fileName);
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_createDocument(fileName);
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}
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catch( std::exception &)
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{
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_clearParser();
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delete _document;
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_document = NULL;
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throw;
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}
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return _document;
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}
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void Parser::_retrieveAllPages(Object * objectWithKids)
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{
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std::string & objectContent = objectWithKids->getObjectContent();
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unsigned int startOfKids = objectContent.find("/Kids");
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unsigned int endOfKids = objectContent.find("]", startOfKids);
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if(
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((int)startOfKids == -1) &&
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((int)objectContent.find("/Page") != -1)
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)
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{
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unsigned int numberOfPages = _document->_pages.size() + 1;
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Page * newPage = new Page(numberOfPages);
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newPage->_root = objectWithKids;
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_document->_pages.insert(std::pair<unsigned int, Page *>(numberOfPages, newPage));
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return;
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}
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const std::vector<Object *> & kids = objectWithKids->getSortedByPositionChildren(startOfKids, endOfKids);
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for(size_t i(0); i < kids.size(); ++i)
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{
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_retrieveAllPages(kids[i]);
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}
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}
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void Parser::_createDocument(const char * docName)
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{
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Q_UNUSED(docName);
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_document->_root = _root;
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std::string & rootContent = _root->getObjectContent();
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unsigned int startOfPages = rootContent.find("/Pages");
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if((int)startOfPages == -1)
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throw Exception("Some document is wrong");
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unsigned int endOfPages = rootContent.find("R", startOfPages);
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std::vector<Object *> objectWithKids = _root->getChildrenByBounds(startOfPages, endOfPages);
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if(objectWithKids.size() != 1)
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throw Exception("Some document is wrong");
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_retrieveAllPages(objectWithKids[0]);
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_root->retrieveMaxObjectNumber(_document->_maxObjectNumber);
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_clearParser();
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}
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void Parser::_clearParser()
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{
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_root = 0;
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_fileContent.clear();
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_fileContent.reserve();
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_objects.clear();
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}
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void Parser::_getFileContent(const char * fileName)
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{
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ifstream pdfFile;
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pdfFile.open (fileName, ios::binary );
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if (pdfFile.fail())
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{
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stringstream errorMessage("File ");
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errorMessage << fileName << " is absent" << "\0";
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throw Exception(errorMessage);
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}
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// get length of file:
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pdfFile.seekg (0, ios::end);
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int length = pdfFile.tellg();
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pdfFile.seekg (0, ios::beg);
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_fileContent.resize(length);
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pdfFile.read(&_fileContent[0], length);
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// check version
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const char *header = "%PDF-1.";
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size_t verPos = _fileContent.find(header);
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if( verPos == 0 )
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{
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verPos += strlen(header);
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char ver = _fileContent[verPos];
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/* As every previous standard is contained in newer ones, a lot of documents that would not use
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* features > 1.4 are probably correctly exportable. Some optimizations and fixes have been added since 1.4, but after some tests I didn't encountered any issues.
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* As an attempt (until 1.5 to 1.7 version can be really supported)to measure what would be the impact of using this library as-is,
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* we allow document with version > 1.4 to be parsed by it.
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* The big advantage to using it is that exported PDFs are real PDFs (with searchable content), not heavy images.
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* If an exception is thrown, actual behavior (heavy images) is used.
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*/
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if( ver < '0' || ver > '7' )
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{
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stringstream errorMsg;
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errorMsg<<" File with verion 1."<<ver<<" is not currently supported by merge library\n";
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throw Exception(errorMsg);
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}
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}
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else
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{
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throw Exception("Unrecognized header of PDF file");
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}
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pdfFile.close();
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}
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void Parser::_createObjectTree(const char * fileName)
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{
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unsigned int rootObjectNumber = 0;
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try
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{
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_getFileContent(fileName);
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_readXRefAndCreateObjects();
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rootObjectNumber = _readTrailerAndReturnRoot();
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}
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catch (std::exception &)
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{
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std::map<unsigned int, Object *>::const_iterator it(_objects.begin());
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for(;it != _objects.end();it++)
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{
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delete (*it).second;
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}
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_objects.clear();
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throw;
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}
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std::map<unsigned int, Object *>::iterator objectsIterator;
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for ( objectsIterator = _objects.begin() ; objectsIterator != _objects.end(); objectsIterator++ )
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{
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Object * currentObject = (*objectsIterator).second;
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_document->_allObjects.push_back(currentObject);
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//key - object number : value - positions in object content of this reference
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const std::map<unsigned int, Object::ReferencePositionsInContent> & refs =
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_getReferences(currentObject->getObjectContent());
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std::map<unsigned int, Object::ReferencePositionsInContent>::const_iterator refsIterator = refs.begin();
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for(; refsIterator != refs.end(); ++refsIterator)
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{
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if(_objects.count((*refsIterator).first))
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currentObject->addChild(_objects[(*refsIterator).first], (*refsIterator).second);
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}
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}
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_root = _objects[rootObjectNumber];
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}
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const std::map<unsigned int, Object::ReferencePositionsInContent> & Parser::_getReferences(const std::string & objectContent)
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{
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unsigned int currentPosition(0), startOfNextSearch(0);
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static std::map<unsigned int, std::vector<unsigned int> > searchResult;
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searchResult.clear();
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unsigned int streamStart = objectContent.find("stream");
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if((int)streamStart == -1)
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streamStart = objectContent.size();
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while(startOfNextSearch < streamStart)
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{
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//try to find reference. reference example is 15 0 R
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startOfNextSearch = objectContent.find(" R", startOfNextSearch);
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currentPosition = startOfNextSearch;
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if((int)currentPosition != -1)
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{
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//check that next character of " R" is WHITESPACE.
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if(((int)WHITESPACES.find(objectContent[currentPosition + 2]) == -1) &&
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((int)DELIMETERS.find(objectContent[currentPosition + 2]) == -1)
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)
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{
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//this is not reference. this is something looks like "0 0 0 RG"
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++startOfNextSearch;
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continue;
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}
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//get previos symbol and check that it is a number
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unsigned int numberSearchCounter = _skipNumber(objectContent, --currentPosition);
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//previos symbol is not a number
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if(numberSearchCounter == currentPosition)
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{
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++startOfNextSearch;
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continue;
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}
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else
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{
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currentPosition = numberSearchCounter;
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}
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bool isFound(false);
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//previos symbols should be whitespaces
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while((objectContent[currentPosition] == ' ') && --currentPosition)
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{
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isFound = true;
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}
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//previos symbol is not a whitespace
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if(!isFound)
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{
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++startOfNextSearch;
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continue;
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}
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//check that this and may be previos symbols are a numbers
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numberSearchCounter = _skipNumber(objectContent, currentPosition);
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if(numberSearchCounter == currentPosition)
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{
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++startOfNextSearch;
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continue;
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}
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unsigned int objectNumber = Utils::stringToInt(objectContent.substr(numberSearchCounter + 1, currentPosition - numberSearchCounter));
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searchResult[objectNumber].push_back(numberSearchCounter + 1);
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++startOfNextSearch;
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}
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else
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break;
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}
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return searchResult;
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}
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unsigned int Parser::_skipNumber(const std::string & str, unsigned int currentPosition)
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{
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unsigned int numberSearchCounter = currentPosition;
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while(((int)NUMBERS.find(str[numberSearchCounter]) != -1) && --numberSearchCounter)
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{}
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return numberSearchCounter;
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}
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void Parser::_readXRefAndCreateObjects()
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{
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unsigned int currentPostion = _getStartOfXrefWithRoot();
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do
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{
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const std::string & currentToken = _getNextToken(currentPostion);
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if(currentToken != "xref")
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{
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throw Exception("Wrong xref in some document");
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}
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unsigned int endOfLine = _getEndOfLineFromContent(currentPostion );
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if(_countTokens(currentPostion, endOfLine) != 2)
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{
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throw Exception("Wrong xref in some document");
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}
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//now we are reading the xref
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while(1)
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{
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Utils::stringToInt(_getNextToken(currentPostion));
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unsigned int objectCount = Utils::stringToInt(_getNextToken(currentPostion));
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for(unsigned int i(0); i < objectCount; i++)
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{
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unsigned long first;
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if(_countTokens(currentPostion, _getEndOfLineFromContent(currentPostion)) == 3)
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{
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first = Utils::stringToInt(_getNextToken(currentPostion));
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Utils::stringToInt(_getNextToken(currentPostion));
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const string & use = _getNextToken(currentPostion);
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if(!use.compare("n"))
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{
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unsigned int objectNumber;
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try
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{
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std::pair<unsigned int, unsigned int> streamBounds;
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bool hasObjectStream;
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unsigned int generationNumber;
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const std::string content = _getObjectContent(first, objectNumber, generationNumber, streamBounds, hasObjectStream);
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if(!_objects.count(objectNumber))
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{
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Object * newObject = new Object(objectNumber, generationNumber, content, _document->_documentName ,streamBounds, hasObjectStream);
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_objects[objectNumber] = newObject;
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}
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}
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catch(std::exception &)
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{
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}
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}
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}
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else
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{
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;
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}
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++currentPostion;
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}
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unsigned int previosPostion = currentPostion;
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const std::string & isTrailer = _getNextToken(currentPostion);
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std::string trailer("trailer");
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if(isTrailer == trailer)
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{
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currentPostion -= trailer.size();
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break;
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}
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else
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currentPostion = previosPostion;
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}
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}
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while(_readTrailerAndRterievePrev(currentPostion, currentPostion));
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}
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unsigned int Parser::_getStartOfXrefWithRoot()
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{
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unsigned int leftBoundOfStartOfXref = _fileContent.rfind("startxref");
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leftBoundOfStartOfXref = _fileContent.find_first_of(NUMBERS, leftBoundOfStartOfXref);
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unsigned int rightBoundOfStartOfXref = _fileContent.find_first_not_of(NUMBERS, leftBoundOfStartOfXref + 1);
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std::string startOfXref = _fileContent.substr(leftBoundOfStartOfXref, rightBoundOfStartOfXref - leftBoundOfStartOfXref);
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int integerStartOfXref = Utils::stringToInt(startOfXref);
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return integerStartOfXref;
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}
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unsigned int Parser::_getEndOfLineFromContent(unsigned int fromPosition)
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{
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fromPosition = _skipWhiteSpacesFromContent(fromPosition);
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unsigned int endOfLine = _fileContent.find_first_of("\n\r", fromPosition);
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endOfLine = _fileContent.find_last_of("\n\r", endOfLine);
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return endOfLine;
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}
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const std::pair<unsigned int, unsigned int> & Parser::_getLineBounds(const std::string & str, unsigned int fromPosition)
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{
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static std::pair<unsigned int, unsigned int> bounds;
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bounds.first = str.rfind('\n', fromPosition);
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if((int)bounds.first == -1)
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bounds.first = 0;
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bounds.second = str.find('\n', fromPosition);
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if((int)bounds.second == -1)
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bounds.second = str.size();
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return bounds;
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}
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const std::string & Parser::_getNextToken(unsigned int & fromPosition)
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{
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fromPosition = _skipWhiteSpacesFromContent(fromPosition);
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unsigned int position = _fileContent.find_first_of(WHITESPACES, fromPosition);
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static std::string token;
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if(position > fromPosition)
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{
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unsigned int tokenSize = position - fromPosition;
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token.resize(tokenSize);
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memcpy(&token[0], &_fileContent[fromPosition], tokenSize);
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fromPosition = position;
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return token;
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}
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else
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{
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//TODO throw exception
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}
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token = "";
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return token;
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}
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unsigned int Parser::_countTokens(unsigned int leftBound, unsigned int rightBount)
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{
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unsigned int position = _skipWhiteSpacesFromContent(leftBound);
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unsigned int tokensCount = 0;
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while (position < rightBount)
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{
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position = _fileContent.find_first_of(WHITESPACES, position);
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if ((int)position != -1)
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++tokensCount;
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//start search from next symbol
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++position;
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}
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return tokensCount;
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}
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unsigned int Parser::_skipWhiteSpaces(const std::string & str, unsigned int fromPosition)
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{
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unsigned int position = fromPosition;
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if((int)WHITESPACES.find(str[0]) != -1)
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position = str.find_first_not_of(WHITESPACES, position);
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return position;
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}
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unsigned int Parser::_skipWhiteSpacesFromContent(unsigned int fromPosition)
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{
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unsigned int position = fromPosition;
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if((int)WHITESPACES.find(_fileContent[position]) != -1)
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position = _fileContent.find_first_not_of(WHITESPACES, position);// + 1;
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return position;
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}
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const std::string & Parser::_getObjectContent(unsigned int objectPosition, unsigned int & objectNumber, unsigned int & generationNumber, std::pair<unsigned int, unsigned int> & streamBounds, bool & hasObjectStream)
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{
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hasObjectStream = false;
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unsigned int currentPosition = objectPosition;
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std::string token = _getNextToken(currentPosition); // number of object
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objectNumber = Utils::stringToInt(token);
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token = _getNextToken(currentPosition); // generation number - not interesting
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generationNumber = Utils::stringToInt(token);
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token = Parser::getNextToken(_fileContent,currentPosition);
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if( token != "obj" )
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{
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std::stringstream strOut;
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strOut<<"Wrong object in PDF, in position "<<currentPosition<<" cannot continue!\n";
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throw Exception(strOut.str());
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}
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static std::string objectContent;
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size_t contentStart = _fileContent.find_first_not_of(Parser::WHITESPACES,currentPosition);
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if((int) contentStart == -1 )
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{
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std::stringstream strOut;
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strOut<<"Wrong object "<< objectNumber<< "in PDF, cannot find content for it\n";
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throw Exception(strOut.str());
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}
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currentPosition = contentStart;
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unsigned int endOfContent = _fileContent.find("endobj", contentStart);
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if((int) endOfContent == -1 )
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{
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stringstream errorMessage("Corrupted PDF file, obj does not have matching endobj");
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throw Exception(errorMessage);
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}
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unsigned int endOfStream = _fileContent.find("endstream", currentPosition);
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if(((int)endOfStream != -1) && (endOfStream < endOfContent))
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{
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std::string stream("stream");
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unsigned int beginOfStream = _fileContent.find(stream, currentPosition) + stream.size();
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while(_fileContent[beginOfStream] == '\r')
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{
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++beginOfStream;
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}
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if( _fileContent[beginOfStream] == '\n')
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{
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++beginOfStream;
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}
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streamBounds.first = beginOfStream;
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// try to use Length field to determine end of stream.
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std::string lengthToken = "/Length";
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size_t lengthBegin = Parser::findTokenName(_fileContent,lengthToken,contentStart);
|
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if ((int) lengthBegin != -1 )
|
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{
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std::string lengthStr;
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size_t lenPos = lengthBegin + lengthToken.size();
|
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bool useContentLength = false;
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if( Parser::getNextWord(lengthStr,_fileContent,lenPos) )
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{
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useContentLength = true;
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std::string refStr;
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if( Parser::getNextWord(refStr,_fileContent,lenPos))
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{
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if( Parser::getNextWord(refStr,_fileContent,lenPos))
|
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{
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if( refStr == "R" )
|
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{
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useContentLength = false;
|
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//it is reference
|
|
}
|
|
}
|
|
}
|
|
}
|
|
if( useContentLength )
|
|
{
|
|
std::stringstream strin(lengthStr);
|
|
unsigned int streamEnd = 0;
|
|
strin>>streamEnd;
|
|
streamEnd += beginOfStream;
|
|
unsigned int streamEndBegin = _fileContent.find("endstream",streamEnd);
|
|
if((int) streamEndBegin != -1 )
|
|
{
|
|
endOfStream = streamEndBegin;
|
|
}
|
|
}
|
|
}
|
|
streamBounds.second = endOfStream;
|
|
endOfContent = beginOfStream;
|
|
hasObjectStream = true;
|
|
|
|
}
|
|
unsigned int contentSize = endOfContent - currentPosition;
|
|
|
|
objectContent.resize(contentSize);
|
|
memcpy(&objectContent[0], &_fileContent[currentPosition], contentSize);
|
|
return objectContent;
|
|
|
|
}
|
|
|
|
unsigned int Parser::_readTrailerAndReturnRoot()
|
|
{
|
|
|
|
unsigned int startOfTrailer = Parser::findToken(_fileContent,"trailer", _getStartOfXrefWithRoot());
|
|
std::string rootStr("/Root");
|
|
unsigned int startOfRoot = Parser::findToken(_fileContent,rootStr.data(), startOfTrailer);
|
|
if((int) startOfRoot == -1)
|
|
{
|
|
throw Exception("Cannot find Root object !");
|
|
}
|
|
std::string encryptStr("/Encrypt");
|
|
if((int) Parser::findToken(_fileContent,encryptStr,startOfTrailer) != -1 )
|
|
{
|
|
throw Exception("Encrypted PDF is not supported!");
|
|
}
|
|
startOfRoot += rootStr.size()+1; //"/Root + ' '
|
|
unsigned int endOfRoot = startOfRoot;
|
|
while((int)NUMBERS.find(_fileContent[endOfRoot++]) != -1)
|
|
{}
|
|
--endOfRoot;
|
|
return Utils::stringToInt(_fileContent.substr(startOfRoot, endOfRoot - startOfRoot));
|
|
}
|
|
|
|
unsigned int Parser::_readTrailerAndRterievePrev(const unsigned int startPositionForSearch, unsigned int & previosXref)
|
|
{
|
|
unsigned int startOfTrailer = Parser::findToken(_fileContent,"trailer", startPositionForSearch);
|
|
if((int) startOfTrailer == -1 )
|
|
{
|
|
throw Exception("Cannot find trailer!");
|
|
}
|
|
|
|
unsigned int startOfPrev = _fileContent.find("Prev ", startOfTrailer);
|
|
unsigned int startxref = _fileContent.find("startxref", startOfTrailer);
|
|
if((int)startOfPrev == -1 || (startOfPrev > startxref))
|
|
return false;
|
|
//"Prev "s length = 5
|
|
else
|
|
startOfPrev += 5;
|
|
|
|
unsigned int endOfPrev = startOfPrev;
|
|
while((int)NUMBERS.find(_fileContent[endOfPrev++]) != -1)
|
|
{}
|
|
--endOfPrev;
|
|
previosXref = Utils::stringToInt(_fileContent.substr(startOfPrev, endOfPrev - startOfPrev));
|
|
return true;
|
|
}
|
|
|
|
//Method finds the token from current position from string
|
|
// It uses PDF whitespaces and delimeters to recognize
|
|
// Returned string without begin/end spaces
|
|
std::string Parser::getNextToken(const std::string &str, unsigned int &position)
|
|
{
|
|
if( position >= str.size() )
|
|
{
|
|
return "";
|
|
}
|
|
//skip first spaces
|
|
size_t beg_pos = str.find_first_not_of(Parser::WHITESPACES,position);
|
|
if ((int) beg_pos == -1 )
|
|
{
|
|
// it is empty string!
|
|
return "";
|
|
}
|
|
size_t end_pos = str.find_first_of(Parser::WHITESPACES_AND_DELIMETERS,beg_pos);
|
|
if ((int) end_pos == -1 )
|
|
{
|
|
end_pos = str.size();
|
|
}
|
|
position = end_pos;
|
|
|
|
std::string out = str.substr(beg_pos,end_pos - beg_pos);
|
|
Parser::trim(out);
|
|
return out;
|
|
}
|
|
/** @brief getNextWord
|
|
*
|
|
* method finds and returns next word from the string
|
|
* For example: " 1 0 R \n" will return "1" , then "0" then "R"
|
|
*/
|
|
bool Parser::getNextWord(std::string &out, const std::string &str, size_t &nextPosition, size_t *found)
|
|
{
|
|
if( found )
|
|
{
|
|
*found = -1;
|
|
}
|
|
//trace("position = %d",position);
|
|
if( nextPosition >= str.size() )
|
|
{
|
|
return false;
|
|
}
|
|
//skip first spaces
|
|
size_t beg_pos = str.find_first_not_of(Parser::WHITESPACES,nextPosition);
|
|
if ((int) beg_pos == -1 )
|
|
{
|
|
// it is empty string!
|
|
return false;
|
|
}
|
|
if( found )
|
|
{
|
|
*found = beg_pos;
|
|
}
|
|
size_t end_pos = str.find_first_of(Parser::WHITESPACES,beg_pos);
|
|
|
|
if ((int) end_pos == -1 )
|
|
{
|
|
end_pos = str.size();
|
|
}
|
|
nextPosition = end_pos;
|
|
out = str.substr(beg_pos,end_pos - beg_pos);
|
|
Parser::trim(out);
|
|
if( out.empty() )
|
|
{
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
/** @brief trim
|
|
*
|
|
* @todo: document this function
|
|
*/
|
|
void Parser::trim(std::string &str)
|
|
{
|
|
std::string::size_type pos1 = str.find_first_not_of(WHITESPACES);
|
|
std::string::size_type pos2 = str.find_last_not_of(WHITESPACES);
|
|
str = str.substr((int)pos1 == -1 ? 0 : pos1,
|
|
(int)pos2 == -1 ? str.length() - 1 : pos2 - pos1 + 1);
|
|
}
|
|
|
|
// Method tries to find the PDF token from the content
|
|
// The token is "/L 12 0R" or /Length 123
|
|
std::string Parser::findTokenStr(const std::string &content, const std::string &pattern, size_t start, size_t &foundStart, size_t &foundEnd)
|
|
{
|
|
size_t cur_pos = Parser::findToken(content,pattern,start);
|
|
if((int) cur_pos == -1 )
|
|
{
|
|
return "";
|
|
}
|
|
foundStart = cur_pos;
|
|
cur_pos += pattern.size();
|
|
// then lets parse the content of remaining part
|
|
size_t end_pos = content.find_first_of(Parser::DELIMETERS,cur_pos);
|
|
if((int) end_pos == -1 )
|
|
{
|
|
end_pos = content.size();
|
|
}
|
|
std::string token = content.substr(cur_pos,end_pos-cur_pos);
|
|
foundEnd = end_pos -1;
|
|
return token;
|
|
}
|
|
|
|
// Method tries to find token in the string from specified position,
|
|
// returns position of first occurent or npos if not found
|
|
// It properly handles cases when content contains strings which
|
|
// contains token but not euqal to it
|
|
// Example: content "/Transparency/ ..." pattern "/Trans
|
|
// will return npos.
|
|
size_t Parser::findToken(const std::string &content, const std::string &keyword,size_t start)
|
|
{
|
|
size_t cur_pos = start;
|
|
// lets find pattern first
|
|
size_t foundStart = -1;
|
|
size_t savedPos = 0;
|
|
while( 1 )
|
|
{
|
|
cur_pos = content.find(keyword,cur_pos);
|
|
if((int) cur_pos == -1 )
|
|
{
|
|
break;
|
|
}
|
|
savedPos = cur_pos;
|
|
cur_pos += keyword.size();
|
|
if( cur_pos < content.size() )
|
|
{
|
|
if((int) Parser::WHITESPACES.find(content[cur_pos]) != -1 ||
|
|
(int)Parser::DELIMETERS.find(content[cur_pos]) != -1 )
|
|
{
|
|
foundStart = savedPos;
|
|
break;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
foundStart = savedPos;
|
|
// end of line is reached
|
|
break;
|
|
}
|
|
}
|
|
return foundStart;
|
|
}
|
|
|
|
// Method checks if token at current position can be a Name or it is not name but value
|
|
// Example
|
|
// /H /P /P 12 0 R
|
|
// the tag /P can be a name (and a value also), while 12 cannot
|
|
// start defines the position of token content
|
|
bool Parser::tokenIsAName(const std::string &content, size_t start )
|
|
{
|
|
std::string openBraces = "<[({";
|
|
bool found = false;
|
|
while(1)
|
|
{
|
|
size_t foundNonWhite = content.find_first_not_of(Parser::WHITESPACES,start);
|
|
size_t foundDelim = content.find_first_of(Parser::DELIMETERS,start);
|
|
|
|
if( (int)foundNonWhite != -1 &&
|
|
(int)foundDelim != -1 )
|
|
{
|
|
if( (foundNonWhite < foundDelim ) || ( (int)openBraces.find(content[foundDelim]) != -1) )
|
|
{
|
|
if( found )
|
|
{
|
|
return false;
|
|
}
|
|
else
|
|
{
|
|
return true;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
if( found )
|
|
{
|
|
return true;
|
|
}
|
|
else
|
|
{
|
|
found = true;
|
|
start = content.find_first_of(Parser::WHITESPACES_AND_DELIMETERS,foundDelim+1);
|
|
}
|
|
}
|
|
}
|
|
else
|
|
{
|
|
return true;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Method tries to find token name in the string from specified position,
|
|
// For example, the string contains /H /P /P 12 0 R.
|
|
// If search for /P then it will return position of /P 12 0 R, not value of
|
|
// /H /P
|
|
size_t Parser::findTokenName(const std::string &content, const std::string &keyword,size_t start)
|
|
{
|
|
size_t cur_pos = start;
|
|
// lets find pattern first
|
|
size_t foundStart = -1;
|
|
size_t savedPos = 0;
|
|
std::string braces = "<[({";
|
|
while( 1 )
|
|
{
|
|
cur_pos = content.find(keyword,cur_pos);
|
|
if((int) cur_pos == -1 )
|
|
{
|
|
break;
|
|
}
|
|
savedPos = cur_pos;
|
|
cur_pos += keyword.size();
|
|
if( cur_pos < content.size() )
|
|
{
|
|
if((int) Parser::WHITESPACES_AND_DELIMETERS.find(content[cur_pos]) != -1 )
|
|
{
|
|
if( tokenIsAName(content,cur_pos ) )
|
|
{
|
|
foundStart = savedPos;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
else
|
|
{
|
|
foundStart = savedPos;
|
|
// end of line is reached
|
|
break;
|
|
}
|
|
}
|
|
return foundStart;
|
|
}
|
|
|
|
unsigned int Parser::findEndOfElementContent(const std::string &content,unsigned int startOfPageElement)
|
|
{
|
|
unsigned int foundEnd = -1;
|
|
std::stack<std::string> delimStack;
|
|
std::string endDelim = "/]>)}";
|
|
unsigned int curPos = startOfPageElement;
|
|
std::string openDict("<");
|
|
std::string openArray("[");
|
|
std::string delimeter = endDelim;
|
|
|
|
delimStack.push(delimeter); //initial delimeter
|
|
|
|
bool compensation = true;
|
|
while(1)
|
|
{
|
|
unsigned int nonWhiteSpace = content.find_first_not_of(Parser::WHITESPACES,curPos);
|
|
|
|
unsigned int foundDelimeter = content.find_first_of(delimeter,curPos);
|
|
unsigned int foundOpenBrace = content.find("[",curPos);
|
|
unsigned int foundOpenDict = content.find("<",curPos);
|
|
|
|
if((int) foundDelimeter == -1 && (int)foundOpenBrace == -1 && (int)foundOpenDict == -1 )
|
|
{
|
|
if( !delimStack.empty() )
|
|
{
|
|
delimStack.pop();
|
|
}
|
|
}
|
|
else if( (foundDelimeter <= foundOpenBrace && foundDelimeter <= foundOpenDict ) )
|
|
{
|
|
if( !delimStack.empty() )
|
|
{
|
|
delimStack.pop();
|
|
}
|
|
if( nonWhiteSpace == foundDelimeter && delimeter == endDelim )
|
|
{
|
|
curPos = foundDelimeter;
|
|
if(content[foundDelimeter] == '/' && compensation )
|
|
{
|
|
curPos ++;
|
|
compensation = false;
|
|
}
|
|
}
|
|
else
|
|
{
|
|
compensation = false;
|
|
if( delimeter == endDelim )
|
|
{
|
|
curPos = foundDelimeter;
|
|
}
|
|
else
|
|
{
|
|
curPos = foundDelimeter + delimeter.size();
|
|
}
|
|
}
|
|
}
|
|
else if( foundOpenBrace <= foundDelimeter && foundOpenBrace <= foundOpenDict )
|
|
{
|
|
compensation = false;
|
|
delimStack.push("]");
|
|
curPos = foundOpenBrace + openArray.size();
|
|
}
|
|
else if( foundOpenDict <= foundDelimeter && foundOpenDict <= foundOpenBrace )
|
|
{
|
|
compensation = false;
|
|
delimStack.push(">");
|
|
curPos = foundOpenDict + openDict.size();
|
|
}
|
|
if( delimStack.empty() )
|
|
{
|
|
foundEnd = content.find_first_of(delimeter,curPos);
|
|
if((int) foundEnd == -1 )
|
|
{
|
|
foundEnd = curPos;
|
|
}
|
|
break;
|
|
}
|
|
delimeter = delimStack.top();
|
|
|
|
}
|
|
return foundEnd;
|
|
}
|
|
|
|
|