sdext/source/pdfimport/inc/pdfparse.hxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
   4  *
   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  *
   9  * This file incorporates work covered by the following license notice:
  10  *
  11  *   Licensed to the Apache Software Foundation (ASF) under one or more
  12  *   contributor license agreements. See the NOTICE file distributed
  13  *   with this work for additional information regarding copyright
  14  *   ownership. The ASF licenses this file to you under the Apache
  15  *   License, Version 2.0 (the "License"); you may not use this file
  16  *   except in compliance with the License. You may obtain a copy of
  17  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  18  */
  19
  20 #ifndef INCLUDED_SDEXT_SOURCE_PDFIMPORT_INC_PDFPARSE_HXX
  21 #define INCLUDED_SDEXT_SOURCE_PDFIMPORT_INC_PDFPARSE_HXX
  22
  23 #include <sal/types.h>
  24 #include <rtl/ustring.hxx>
  25 #include <rtl/string.hxx>
  26
  27 #include <unordered_map>
  28 #include <vector>
  29 #include <memory>
  30
  31 namespace pdfparse
  32 {
  33
  34 struct EmitImplData;
  35 struct PDFContainer;
  36 class EmitContext
  37 {
  38 public:
  39     virtual bool write( const void* pBuf, unsigned int nLen ) = 0;
  40     virtual unsigned int getCurPos() = 0;
  41     virtual bool copyOrigBytes( unsigned int nOrigOffset, unsigned int nLen ) = 0;
  42     virtual unsigned int readOrigBytes( unsigned int nOrigOffset, unsigned int nLen, void* pBuf ) = 0;
  43
  44     explicit EmitContext( const PDFContainer* pTop = nullptr );
  45     virtual ~EmitContext();
  46
  47     // set this to deflate contained streams
  48     bool m_bDeflate;
  49     // set this to decrypt the PDF file
  50     bool m_bDecrypt;
  51
  52 private:
  53     friend struct PDFEntry;
  54     std::unique_ptr<EmitImplData> m_pImplData;
  55 };
  56
  57 struct PDFEntry
  58 {
  59     PDFEntry() {}
  60     virtual ~PDFEntry();
  61
  62     virtual bool emit( EmitContext& rWriteContext ) const = 0;
  63     virtual PDFEntry* clone() const = 0;
  64
  65 protected:
  66     static EmitImplData* getEmitData( EmitContext const & rContext );
  67     static void setEmitData( EmitContext& rContext, EmitImplData* pNewEmitData );
  68 };
  69
  70 struct PDFComment : public PDFEntry
  71 {
  72     OString  m_aComment;
  73
  74     explicit PDFComment( const OString& rComment )
  75     : PDFEntry(), m_aComment( rComment ) {}
  76     virtual ~PDFComment() override;
  77     virtual bool emit( EmitContext& rWriteContext ) const override;
  78     virtual PDFEntry* clone() const override;
  79 };
  80
  81 struct PDFValue : public PDFEntry
  82 {
  83     // abstract base class for simple values
  84     PDFValue() : PDFEntry() {}
  85     virtual ~PDFValue() override;
  86 };
  87
  88 struct PDFName : public PDFValue
  89 {
  90     OString  m_aName;
  91
  92     explicit PDFName( const OString& rName )
  93     : PDFValue(), m_aName( rName ) {}
  94     virtual ~PDFName() override;
  95     virtual bool emit( EmitContext& rWriteContext ) const override;
  96     virtual PDFEntry* clone() const override;
  97
  98     OUString getFilteredName() const;
  99 };
 100
 101 struct PDFString : public PDFValue
 102 {
 103     OString  m_aString;
 104
 105     explicit PDFString( const OString& rString )
 106     : PDFValue(), m_aString( rString ) {}
 107     virtual ~PDFString() override;
 108     virtual bool emit( EmitContext& rWriteContext ) const override;
 109     virtual PDFEntry* clone() const override;
 110
 111     OString getFilteredString() const;
 112 };
 113
 114 struct PDFNumber : public PDFValue
 115 {
 116     double m_fValue;
 117
 118     explicit PDFNumber( double fVal )
 119     : PDFValue(), m_fValue( fVal ) {}
 120     virtual ~PDFNumber() override;
 121     virtual bool emit( EmitContext& rWriteContext ) const override;
 122     virtual PDFEntry* clone() const override;
 123 };
 124
 125 struct PDFBool : public PDFValue
 126 {
 127     bool m_bValue;
 128
 129     explicit PDFBool( bool bVal )
 130     : PDFValue(), m_bValue( bVal ) {}
 131     virtual ~PDFBool() override;
 132     virtual bool emit( EmitContext& rWriteContext ) const override;
 133     virtual PDFEntry* clone() const override;
 134 };
 135
 136 struct PDFObjectRef : public PDFValue
 137 {
 138     unsigned int    m_nNumber;
 139     unsigned int    m_nGeneration;
 140
 141     PDFObjectRef( unsigned int nNr, unsigned int nGen )
 142     : PDFValue(), m_nNumber( nNr ), m_nGeneration( nGen ) {}
 143     virtual ~PDFObjectRef() override;
 144     virtual bool emit( EmitContext& rWriteContext ) const override;
 145     virtual PDFEntry* clone() const override;
 146 };
 147
 148 struct PDFNull : public PDFValue
 149 {
 150     PDFNull() {}
 151     virtual ~PDFNull() override;
 152     virtual bool emit( EmitContext& rWriteContext ) const override;
 153     virtual PDFEntry* clone() const override;
 154 };
 155
 156 struct PDFObject;
 157 struct PDFContainer : public PDFEntry
 158 {
 159     sal_Int32              m_nOffset;
 160     std::vector<std::unique_ptr<PDFEntry>> m_aSubElements;
 161
 162     // this is an abstract base class for identifying
 163     // entries that can contain sub elements besides comments
 164     PDFContainer() : PDFEntry(), m_nOffset( 0 ) {}
 165     virtual ~PDFContainer() override;
 166     bool emitSubElements( EmitContext& rWriteContext ) const;
 167     void cloneSubElements( std::vector<std::unique_ptr<PDFEntry>>& rNewSubElements ) const;
 168
 169     PDFObject* findObject( unsigned int nNumber, unsigned int nGeneration ) const;
 170     PDFObject* findObject( PDFObjectRef const * pRef ) const
 171     { return findObject( pRef->m_nNumber, pRef->m_nGeneration ); }
 172 };
 173
 174 struct PDFArray : public PDFContainer
 175 {
 176     PDFArray() {}
 177     virtual ~PDFArray() override;
 178     virtual bool emit( EmitContext& rWriteContext ) const override;
 179     virtual PDFEntry* clone() const override;
 180 };
 181
 182 struct PDFDict : public PDFContainer
 183 {
 184     typedef std::unordered_map<OString,PDFEntry*> Map;
 185     Map m_aMap;
 186
 187     PDFDict() {}
 188     virtual ~PDFDict() override;
 189     virtual bool emit( EmitContext& rWriteContext ) const override;
 190     virtual PDFEntry* clone() const override;
 191
 192     // inserting a value of NULL will remove rName and the previous value
 193     // from the dictionary
 194     void insertValue( const OString& rName, PDFEntry* pValue );
 195     // removes a name/value pair from the dict
 196     void eraseValue( const OString& rName );
 197     // builds new map as of sub elements
 198     // returns NULL if successful, else the first offending element
 199     PDFEntry* buildMap();
 200 };
 201
 202 struct PDFStream : public PDFEntry
 203 {
 204     unsigned int    m_nBeginOffset;
 205     unsigned int    m_nEndOffset; // offset of the byte after the stream
 206     PDFDict*        m_pDict;
 207
 208     PDFStream( unsigned int nBegin, unsigned int nEnd, PDFDict* pStreamDict )
 209     : PDFEntry(), m_nBeginOffset( nBegin ), m_nEndOffset( nEnd ), m_pDict( pStreamDict ) {}
 210     virtual ~PDFStream() override;
 211     virtual bool emit( EmitContext& rWriteContext ) const override;
 212     virtual PDFEntry* clone() const override;
 213
 214     unsigned int getDictLength( const PDFContainer* pObjectContainer ) const; // get contents of the "Length" entry of the dict
 215 };
 216
 217 struct PDFTrailer : public PDFContainer
 218 {
 219     PDFDict*        m_pDict;
 220
 221     PDFTrailer() : PDFContainer(), m_pDict( nullptr ) {}
 222     virtual ~PDFTrailer() override;
 223     virtual bool emit( EmitContext& rWriteContext ) const override;
 224     virtual PDFEntry* clone() const override;
 225 };
 226
 227 struct PDFFileImplData;
 228 struct PDFFile : public PDFContainer
 229 {
 230 private:
 231     mutable std::unique_ptr<PDFFileImplData> m_pData;
 232     PDFFileImplData*            impl_getData() const;
 233 public:
 234     unsigned int        m_nMajor;           // PDF major
 235     unsigned int        m_nMinor;           // PDF minor
 236
 237     PDFFile();
 238     virtual ~PDFFile() override;
 239
 240     virtual bool emit( EmitContext& rWriteContext ) const override;
 241     virtual PDFEntry* clone() const override;
 242
 243     bool isEncrypted() const;
 244
 245     bool usesSupportedEncryptionFormat() const;
 246
 247     // this method checks whether rPwd is compatible with
 248     // either user or owner password and sets up decrypt data in that case
 249     // returns true if decryption can be done
 250     bool setupDecryptionData( const OString& rPwd ) const;
 251
 252     bool decrypt( const sal_uInt8* pInBuffer, sal_uInt32 nLen,
 253                   sal_uInt8* pOutBuffer,
 254                   unsigned int nObject, unsigned int nGeneration ) const;
 255 };
 256
 257 struct PDFObject : public PDFContainer
 258 {
 259     PDFEntry*       m_pObject;
 260     PDFStream*      m_pStream;
 261     unsigned int    m_nNumber;
 262     unsigned int    m_nGeneration;
 263
 264     PDFObject( unsigned int nNr, unsigned int nGen )
 265     : m_pObject( nullptr ), m_pStream( nullptr ), m_nNumber( nNr ), m_nGeneration( nGen ) {}
 266     virtual ~PDFObject() override;
 267     virtual bool emit( EmitContext& rWriteContext ) const override;
 268     virtual PDFEntry* clone() const override;
 269
 270     // writes only the contained stream, deflated if necessary
 271     void writeStream( EmitContext& rContext, const PDFFile* pPDFFile ) const;
 272
 273 private:
 274     // returns true if stream is deflated
 275     // fills *ppStream and *pBytes with start of stream and count of bytes
 276     // memory returned in *ppStream must be freed with rtl_freeMemory afterwards
 277     // fills in NULL and 0 in case of error
 278     bool getDeflatedStream( char** ppStream, unsigned int* pBytes, const PDFContainer* pObjectContainer, EmitContext& rContext ) const;
 279 };
 280
 281 struct PDFPart : public PDFContainer
 282 {
 283     PDFPart() : PDFContainer() {}
 284     virtual ~PDFPart() override;
 285     virtual bool emit( EmitContext& rWriteContext ) const override;
 286     virtual PDFEntry* clone() const override;
 287 };
 288
 289 class PDFReader
 290 {
 291 public:
 292     PDFReader() {}
 293
 294     static PDFEntry* read( const char* pFileName );
 295 #ifdef _WIN32
 296     static PDFEntry* read( const char* pBuffer, unsigned int nLen );
 297 #endif
 298 };
 299
 300 } // namespace
 301
 302 #endif
 303
 304 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */