sc/source/ui/unoobj/scdetect.cxx

   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 #include "scdetect.hxx"
  21
  22 #include <sal/macros.h>
  23
  24 #include <com/sun/star/beans/PropertyValue.hpp>
  25 #include <com/sun/star/uno/XComponentContext.hpp>
  26 #include <cppuhelper/supportsservice.hxx>
  27 #include <com/sun/star/io/XInputStream.hpp>
  28 #include <unotools/mediadescriptor.hxx>
  29 #include <sfx2/docfile.hxx>
  30 #include <sfx2/docfilt.hxx>
  31 #include <sfx2/fcontnr.hxx>
  32
  33 using namespace ::com::sun::star;
  34 using utl::MediaDescriptor;
  35
  36 namespace {
  37
  38 // table with search pattern
  39 // meaning of the sequences
  40 // 0x00??: the exact byte 0x?? must be at that place
  41 // 0x0100: read over a byte (don't care)
  42 // 0x02nn: a byte of 0xnn variations follows
  43 // 0x8000: recognition finished
  44
  45 #define M_DC        0x0100
  46 #define M_ALT(CNT)  (0x0200+(CNT))
  47 #define M_END       0x8000
  48
  49 const sal_uInt16 pLotus[] =      // Lotus 1/1A/2
  50     { 0x0000, 0x0000, 0x0002, 0x0000,
  51     M_ALT(2), 0x0004, 0x0006,
  52     0x0004, M_END };
  53
  54 const sal_uInt16 pLotusNew[] =   // Lotus >= 9.7
  55     { 0x0000, 0x0000, M_DC, 0x0000,     // Rec# + Len (0x1a)
  56       M_ALT(3), 0x0003, 0x0004, 0x0005, // File Revision Code 97->ME
  57       0x0010, 0x0004, 0x0000, 0x0000,
  58       M_END };
  59
  60 const sal_uInt16 pLotus2[] =     // Lotus >3
  61     { 0x0000, 0x0000, 0x001A, 0x0000,   // Rec# + Len (26)
  62     M_ALT(2), 0x0000, 0x0002,         // File Revision Code
  63     0x0010,
  64     0x0004, 0x0000,                   // File Revision Subcode
  65     M_END };
  66
  67 const sal_uInt16 pQPro[] =
  68        { 0x0000, 0x0000, 0x0002, 0x0000,
  69          M_ALT(4), 0x0001, 0x0002, // WB1, WB2
  70          0x0006, 0x0007,           // QPro 6/7 (?)
  71          0x0010,
  72          M_END };
  73
  74 const sal_uInt16 pDIF1[] =       // DIF with CR-LF
  75     {
  76     'T', 'A', 'B', 'L', 'E',
  77     M_DC, M_DC,
  78     '0', ',', '1',
  79     M_DC, M_DC,
  80     '\"',
  81     M_END };
  82
  83 const sal_uInt16 pDIF2[] =       // DIF with CR or LF
  84     {
  85     'T', 'A', 'B', 'L', 'E',
  86     M_DC,
  87     '0', ',', '1',
  88     M_DC,
  89     '\"',
  90     M_END };
  91
  92 const sal_uInt16 pSylk[] =       // Sylk
  93     {
  94     'I', 'D', ';',
  95     M_ALT(3), 'P', 'N', 'E',        // 'P' plus undocumented Excel extensions 'N' and 'E'
  96     M_END };
  97
  98 bool detectThisFormat(SvStream& rStr, const sal_uInt16* pSearch)
  99 {
 100     sal_uInt8 nByte;
 101     rStr.Seek( 0 ); // in the beginning everything was bad...
 102     rStr.ReadUChar( nByte );
 103     bool bSync = true;
 104     while( !rStr.eof() && bSync )
 105     {
 106         sal_uInt16 nMuster = *pSearch;
 107
 108         if( nMuster < 0x0100 )
 109         { // compare bytes
 110             if( static_cast<sal_uInt8>(nMuster) != nByte )
 111                 bSync = false;
 112         }
 113         else if( nMuster & M_DC )
 114         { // don't care
 115         }
 116         else if( nMuster & M_ALT(0) )
 117         { // alternative Bytes
 118             sal_uInt8 nCntAlt = static_cast<sal_uInt8>(nMuster);
 119             bSync = false;          // first unsynchron
 120             while( nCntAlt > 0 )
 121             {
 122                 pSearch++;
 123                 if( static_cast<sal_uInt8>(*pSearch) == nByte )
 124                     bSync = true;   // only now synchronization
 125                 nCntAlt--;
 126             }
 127         }
 128         else if( nMuster & M_END )
 129         { // Format detected
 130             return true;
 131         }
 132
 133         pSearch++;
 134         rStr.ReadUChar( nByte );
 135     }
 136
 137     return false;
 138 }
 139
 140 }
 141
 142 ScFilterDetect::ScFilterDetect()
 143 {
 144 }
 145
 146 ScFilterDetect::~ScFilterDetect()
 147 {
 148 }
 149
 150 #if 0
 151 // This method is no longer used, but I do want to keep this for now to see
 152 // if we could transfer this check to the now centralized ascii detection
 153 // code in the filter module.
 154 static sal_Bool lcl_MayBeAscii( SvStream& rStream )
 155 {
 156     // ASCII/CSV is considered possible if there are no null bytes, or a Byte
 157     // Order Mark is present, or if, for Unicode UCS2/UTF-16, all null bytes
 158     // are on either even or uneven byte positions.
 159
 160     rStream.Seek(STREAM_SEEK_TO_BEGIN);
 161
 162     const size_t nBufSize = 2048;
 163     sal_uInt16 aBuffer[ nBufSize ];
 164     sal_uInt8* pByte = reinterpret_cast<sal_uInt8*>(aBuffer);
 165     sal_uLong nBytesRead = rStream.Read( pByte, nBufSize*2);
 166
 167     if ( nBytesRead >= 2 && (aBuffer[0] == 0xfffe || aBuffer[0] == 0xfeff) )
 168     {
 169         // Unicode BOM file may contain null bytes.
 170         return sal_True;
 171     }
 172
 173     const sal_uInt16* p = aBuffer;
 174     sal_uInt16 nMask = 0xffff;
 175     nBytesRead /= 2;
 176     while( nBytesRead-- && nMask )
 177     {
 178         sal_uInt16 nVal = *p++ & nMask;
 179         if (!(nVal & 0x00ff))
 180             nMask &= 0xff00;
 181         if (!(nVal & 0xff00))
 182             nMask &= 0x00ff;
 183     }
 184
 185     return nMask != 0;
 186 }
 187 #endif
 188
 189 static bool lcl_MayBeDBase( SvStream& rStream )
 190 {
 191     // Look for dbf marker, see connectivity/source/inc/dbase/DTable.hxx
 192     // DBFType for values.
 193     const sal_uInt8 nValidMarks[] = {
 194         0x03, 0x04, 0x05, 0x30, 0x31, 0x43, 0xB3, 0x83, 0x8b, 0x8e, 0xf5 };
 195     sal_uInt8 nMark;
 196     rStream.Seek(STREAM_SEEK_TO_BEGIN);
 197     rStream.ReadUChar( nMark );
 198     bool bValidMark = false;
 199     for (size_t i=0; i < SAL_N_ELEMENTS(nValidMarks) && !bValidMark; ++i)
 200     {
 201         if (nValidMarks[i] == nMark)
 202             bValidMark = true;
 203     }
 204     if ( !bValidMark )
 205         return false;
 206
 207     const size_t nHeaderBlockSize = 32;
 208     // Empty dbf is >= 32*2+1 bytes in size.
 209     const size_t nEmptyDbf = nHeaderBlockSize * 2 + 1;
 210
 211     sal_uInt64 nSize = rStream.TellEnd();
 212     if ( nSize < nEmptyDbf )
 213         return false;
 214
 215     // count of records at 4
 216     rStream.Seek(4);
 217     sal_uInt32 nRecords(0);
 218     rStream.ReadUInt32(nRecords);
 219
 220     // length of header starts at 8
 221     rStream.Seek(8);
 222     sal_uInt16 nHeaderLen;
 223     rStream.ReadUInt16( nHeaderLen );
 224
 225     // size of record at 10
 226     sal_uInt16 nRecordSize(0);
 227     rStream.ReadUInt16(nRecordSize);
 228
 229     if ( nHeaderLen < nEmptyDbf || nSize < nHeaderLen )
 230         return false;
 231
 232     // see DTable.cxx ODbaseTable::readHeader()
 233     if (0 == nRecordSize)
 234         return false;
 235
 236     // see DTable.cxx ODbaseTable::construct() line 546
 237     if (0 == nRecords)
 238     {
 239         nRecords = (nSize - nHeaderLen) / nRecordSize;
 240     }
 241
 242     // tdf#84834 sanity check of size
 243     // tdf#106423: a dbf file can have 0 record, so no need to check nRecords
 244     if (nSize < nHeaderLen + nRecords * sal_uInt64(nRecordSize))
 245         return false;
 246
 247     // Last byte of header must be 0x0d, this is how it's specified.
 248     // #i9581#,#i26407# but some applications don't follow the specification
 249     // and pad the header with one byte 0x00 to reach an
 250     // even boundary. Some (#i88577# ) even pad more or pad using a 0x1a ^Z
 251     // control character (#i8857#). This results in:
 252     // Last byte of header must be 0x0d on 32 bytes boundary.
 253     sal_uInt16 nBlocks = (nHeaderLen - 1) / nHeaderBlockSize;
 254     sal_uInt8 nEndFlag = 0;
 255     while ( nBlocks > 1 && nEndFlag != 0x0d ) {
 256         rStream.Seek( nBlocks-- * nHeaderBlockSize );
 257         rStream.ReadUChar( nEndFlag );
 258     }
 259
 260     return ( 0x0d == nEndFlag );
 261 }
 262
 263 OUString SAL_CALL ScFilterDetect::detect( uno::Sequence<beans::PropertyValue>& lDescriptor )
 264 {
 265     MediaDescriptor aMediaDesc( lDescriptor );
 266     OUString aTypeName = aMediaDesc.getUnpackedValueOrDefault( MediaDescriptor::PROP_TYPENAME, OUString() );
 267     uno::Reference< io::XInputStream > xStream ( aMediaDesc[MediaDescriptor::PROP_INPUTSTREAM], uno::UNO_QUERY );
 268     if ( !xStream.is() )
 269         return OUString();
 270
 271     SfxMedium aMedium;
 272     aMedium.UseInteractionHandler( false );
 273     aMedium.setStreamToLoadFrom( xStream, true );
 274
 275     SvStream* pStream = aMedium.GetInStream();
 276     if ( !pStream || pStream->GetError() )
 277         // No stream, no detection.
 278         return OUString();
 279
 280     const char* pSearchFilterName = nullptr;
 281     if (aTypeName == "calc_Lotus")
 282     {
 283         if (!detectThisFormat(*pStream, pLotus) && !detectThisFormat(*pStream, pLotusNew) && !detectThisFormat(*pStream, pLotus2))
 284             return OUString();
 285
 286         pSearchFilterName = "Lotus";
 287     }
 288     else if (aTypeName == "calc_QPro")
 289     {
 290         if (!detectThisFormat(*pStream, pQPro))
 291             return OUString();
 292
 293         pSearchFilterName = "Quattro Pro 6.0";
 294     }
 295     else if (aTypeName == "calc_SYLK")
 296     {
 297         if (!detectThisFormat(*pStream, pSylk))
 298             return OUString();
 299
 300         pSearchFilterName = "SYLK";
 301     }
 302     else if (aTypeName == "calc_DIF")
 303     {
 304         if (!detectThisFormat(*pStream, pDIF1) && !detectThisFormat(*pStream, pDIF2))
 305             return OUString();
 306
 307         pSearchFilterName = "DIF";
 308     }
 309     else if (aTypeName == "calc_dBase")
 310     {
 311         if (!lcl_MayBeDBase(*pStream))
 312             return OUString();
 313
 314         pSearchFilterName = "dBase";
 315     }
 316     else
 317         return OUString();
 318
 319     SfxFilterMatcher aMatcher(u"scalc"_ustr);
 320     std::shared_ptr<const SfxFilter> pFilter = aMatcher.GetFilter4FilterName(OUString::createFromAscii(pSearchFilterName));
 321
 322     if (!pFilter)
 323         return OUString();
 324
 325     aMediaDesc[MediaDescriptor::PROP_FILTERNAME] <<= pFilter->GetName();
 326     aMediaDesc >> lDescriptor;
 327     return aTypeName;
 328 }
 329
 330 OUString SAL_CALL ScFilterDetect::getImplementationName()
 331 {
 332     return u"com.sun.star.comp.calc.FormatDetector"_ustr;
 333 }
 334
 335 sal_Bool ScFilterDetect::supportsService( const OUString& sServiceName )
 336 {
 337     return cppu::supportsService(this, sServiceName);
 338 }
 339
 340 css::uno::Sequence<OUString> ScFilterDetect::getSupportedServiceNames()
 341 {
 342     return { u"com.sun.star.frame.ExtendedTypeDetection"_ustr };
 343 }
 344
 345 extern "C" SAL_DLLPUBLIC_EXPORT css::uno::XInterface*
 346 com_sun_star_comp_calc_FormatDetector_get_implementation(css::uno::XComponentContext* /*context*/,
 347                                                          css::uno::Sequence<css::uno::Any> const &)
 348 {
 349     return cppu::acquire(new ScFilterDetect);
 350 }
 351
 352
 353 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */