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libreoffice/sc/source/ui/unoobj/scdetect.cxx
Daniel Baumann 8e63e14cf6
Adding upstream version 4:25.2.3.
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
2025-06-22 16:20:04 +02:00

353 lines
10 KiB
C++

/* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
/*
* This file is part of the LibreOffice project.
*
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
* file, You can obtain one at http://mozilla.org/MPL/2.0/.
*
* This file incorporates work covered by the following license notice:
*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed
* with this work for additional information regarding copyright
* ownership. The ASF licenses this file to you under the Apache
* License, Version 2.0 (the "License"); you may not use this file
* except in compliance with the License. You may obtain a copy of
* the License at http://www.apache.org/licenses/LICENSE-2.0 .
*/
#include "scdetect.hxx"
#include <sal/macros.h>
#include <com/sun/star/beans/PropertyValue.hpp>
#include <com/sun/star/uno/XComponentContext.hpp>
#include <cppuhelper/supportsservice.hxx>
#include <com/sun/star/io/XInputStream.hpp>
#include <unotools/mediadescriptor.hxx>
#include <sfx2/docfile.hxx>
#include <sfx2/docfilt.hxx>
#include <sfx2/fcontnr.hxx>
using namespace ::com::sun::star;
using utl::MediaDescriptor;
namespace {
// table with search pattern
// meaning of the sequences
// 0x00??: the exact byte 0x?? must be at that place
// 0x0100: read over a byte (don't care)
// 0x02nn: a byte of 0xnn variations follows
// 0x8000: recognition finished
#define M_DC 0x0100
#define M_ALT(CNT) (0x0200+(CNT))
#define M_END 0x8000
const sal_uInt16 pLotus[] = // Lotus 1/1A/2
{ 0x0000, 0x0000, 0x0002, 0x0000,
M_ALT(2), 0x0004, 0x0006,
0x0004, M_END };
const sal_uInt16 pLotusNew[] = // Lotus >= 9.7
{ 0x0000, 0x0000, M_DC, 0x0000, // Rec# + Len (0x1a)
M_ALT(3), 0x0003, 0x0004, 0x0005, // File Revision Code 97->ME
0x0010, 0x0004, 0x0000, 0x0000,
M_END };
const sal_uInt16 pLotus2[] = // Lotus >3
{ 0x0000, 0x0000, 0x001A, 0x0000, // Rec# + Len (26)
M_ALT(2), 0x0000, 0x0002, // File Revision Code
0x0010,
0x0004, 0x0000, // File Revision Subcode
M_END };
const sal_uInt16 pQPro[] =
{ 0x0000, 0x0000, 0x0002, 0x0000,
M_ALT(4), 0x0001, 0x0002, // WB1, WB2
0x0006, 0x0007, // QPro 6/7 (?)
0x0010,
M_END };
const sal_uInt16 pDIF1[] = // DIF with CR-LF
{
'T', 'A', 'B', 'L', 'E',
M_DC, M_DC,
'0', ',', '1',
M_DC, M_DC,
'\"',
M_END };
const sal_uInt16 pDIF2[] = // DIF with CR or LF
{
'T', 'A', 'B', 'L', 'E',
M_DC,
'0', ',', '1',
M_DC,
'\"',
M_END };
const sal_uInt16 pSylk[] = // Sylk
{
'I', 'D', ';',
M_ALT(3), 'P', 'N', 'E', // 'P' plus undocumented Excel extensions 'N' and 'E'
M_END };
bool detectThisFormat(SvStream& rStr, const sal_uInt16* pSearch)
{
sal_uInt8 nByte;
rStr.Seek( 0 ); // in the beginning everything was bad...
rStr.ReadUChar( nByte );
bool bSync = true;
while( !rStr.eof() && bSync )
{
sal_uInt16 nMuster = *pSearch;
if( nMuster < 0x0100 )
{ // compare bytes
if( static_cast<sal_uInt8>(nMuster) != nByte )
bSync = false;
}
else if( nMuster & M_DC )
{ // don't care
}
else if( nMuster & M_ALT(0) )
{ // alternative Bytes
sal_uInt8 nCntAlt = static_cast<sal_uInt8>(nMuster);
bSync = false; // first unsynchron
while( nCntAlt > 0 )
{
pSearch++;
if( static_cast<sal_uInt8>(*pSearch) == nByte )
bSync = true; // only now synchronization
nCntAlt--;
}
}
else if( nMuster & M_END )
{ // Format detected
return true;
}
pSearch++;
rStr.ReadUChar( nByte );
}
return false;
}
}
ScFilterDetect::ScFilterDetect()
{
}
ScFilterDetect::~ScFilterDetect()
{
}
#if 0
// This method is no longer used, but I do want to keep this for now to see
// if we could transfer this check to the now centralized ascii detection
// code in the filter module.
static sal_Bool lcl_MayBeAscii( SvStream& rStream )
{
// ASCII/CSV is considered possible if there are no null bytes, or a Byte
// Order Mark is present, or if, for Unicode UCS2/UTF-16, all null bytes
// are on either even or uneven byte positions.
rStream.Seek(STREAM_SEEK_TO_BEGIN);
const size_t nBufSize = 2048;
sal_uInt16 aBuffer[ nBufSize ];
sal_uInt8* pByte = reinterpret_cast<sal_uInt8*>(aBuffer);
sal_uLong nBytesRead = rStream.Read( pByte, nBufSize*2);
if ( nBytesRead >= 2 && (aBuffer[0] == 0xfffe || aBuffer[0] == 0xfeff) )
{
// Unicode BOM file may contain null bytes.
return sal_True;
}
const sal_uInt16* p = aBuffer;
sal_uInt16 nMask = 0xffff;
nBytesRead /= 2;
while( nBytesRead-- && nMask )
{
sal_uInt16 nVal = *p++ & nMask;
if (!(nVal & 0x00ff))
nMask &= 0xff00;
if (!(nVal & 0xff00))
nMask &= 0x00ff;
}
return nMask != 0;
}
#endif
static bool lcl_MayBeDBase( SvStream& rStream )
{
// Look for dbf marker, see connectivity/source/inc/dbase/DTable.hxx
// DBFType for values.
const sal_uInt8 nValidMarks[] = {
0x03, 0x04, 0x05, 0x30, 0x31, 0x43, 0xB3, 0x83, 0x8b, 0x8e, 0xf5 };
sal_uInt8 nMark;
rStream.Seek(STREAM_SEEK_TO_BEGIN);
rStream.ReadUChar( nMark );
bool bValidMark = false;
for (size_t i=0; i < SAL_N_ELEMENTS(nValidMarks) && !bValidMark; ++i)
{
if (nValidMarks[i] == nMark)
bValidMark = true;
}
if ( !bValidMark )
return false;
const size_t nHeaderBlockSize = 32;
// Empty dbf is >= 32*2+1 bytes in size.
const size_t nEmptyDbf = nHeaderBlockSize * 2 + 1;
sal_uInt64 nSize = rStream.TellEnd();
if ( nSize < nEmptyDbf )
return false;
// count of records at 4
rStream.Seek(4);
sal_uInt32 nRecords(0);
rStream.ReadUInt32(nRecords);
// length of header starts at 8
rStream.Seek(8);
sal_uInt16 nHeaderLen;
rStream.ReadUInt16( nHeaderLen );
// size of record at 10
sal_uInt16 nRecordSize(0);
rStream.ReadUInt16(nRecordSize);
if ( nHeaderLen < nEmptyDbf || nSize < nHeaderLen )
return false;
// see DTable.cxx ODbaseTable::readHeader()
if (0 == nRecordSize)
return false;
// see DTable.cxx ODbaseTable::construct() line 546
if (0 == nRecords)
{
nRecords = (nSize - nHeaderLen) / nRecordSize;
}
// tdf#84834 sanity check of size
// tdf#106423: a dbf file can have 0 record, so no need to check nRecords
if (nSize < nHeaderLen + nRecords * sal_uInt64(nRecordSize))
return false;
// Last byte of header must be 0x0d, this is how it's specified.
// #i9581#,#i26407# but some applications don't follow the specification
// and pad the header with one byte 0x00 to reach an
// even boundary. Some (#i88577# ) even pad more or pad using a 0x1a ^Z
// control character (#i8857#). This results in:
// Last byte of header must be 0x0d on 32 bytes boundary.
sal_uInt16 nBlocks = (nHeaderLen - 1) / nHeaderBlockSize;
sal_uInt8 nEndFlag = 0;
while ( nBlocks > 1 && nEndFlag != 0x0d ) {
rStream.Seek( nBlocks-- * nHeaderBlockSize );
rStream.ReadUChar( nEndFlag );
}
return ( 0x0d == nEndFlag );
}
OUString SAL_CALL ScFilterDetect::detect( uno::Sequence<beans::PropertyValue>& lDescriptor )
{
MediaDescriptor aMediaDesc( lDescriptor );
OUString aTypeName = aMediaDesc.getUnpackedValueOrDefault( MediaDescriptor::PROP_TYPENAME, OUString() );
uno::Reference< io::XInputStream > xStream ( aMediaDesc[MediaDescriptor::PROP_INPUTSTREAM], uno::UNO_QUERY );
if ( !xStream.is() )
return OUString();
SfxMedium aMedium;
aMedium.UseInteractionHandler( false );
aMedium.setStreamToLoadFrom( xStream, true );
SvStream* pStream = aMedium.GetInStream();
if ( !pStream || pStream->GetError() )
// No stream, no detection.
return OUString();
const char* pSearchFilterName = nullptr;
if (aTypeName == "calc_Lotus")
{
if (!detectThisFormat(*pStream, pLotus) && !detectThisFormat(*pStream, pLotusNew) && !detectThisFormat(*pStream, pLotus2))
return OUString();
pSearchFilterName = "Lotus";
}
else if (aTypeName == "calc_QPro")
{
if (!detectThisFormat(*pStream, pQPro))
return OUString();
pSearchFilterName = "Quattro Pro 6.0";
}
else if (aTypeName == "calc_SYLK")
{
if (!detectThisFormat(*pStream, pSylk))
return OUString();
pSearchFilterName = "SYLK";
}
else if (aTypeName == "calc_DIF")
{
if (!detectThisFormat(*pStream, pDIF1) && !detectThisFormat(*pStream, pDIF2))
return OUString();
pSearchFilterName = "DIF";
}
else if (aTypeName == "calc_dBase")
{
if (!lcl_MayBeDBase(*pStream))
return OUString();
pSearchFilterName = "dBase";
}
else
return OUString();
SfxFilterMatcher aMatcher(u"scalc"_ustr);
std::shared_ptr<const SfxFilter> pFilter = aMatcher.GetFilter4FilterName(OUString::createFromAscii(pSearchFilterName));
if (!pFilter)
return OUString();
aMediaDesc[MediaDescriptor::PROP_FILTERNAME] <<= pFilter->GetName();
aMediaDesc >> lDescriptor;
return aTypeName;
}
OUString SAL_CALL ScFilterDetect::getImplementationName()
{
return u"com.sun.star.comp.calc.FormatDetector"_ustr;
}
sal_Bool ScFilterDetect::supportsService( const OUString& sServiceName )
{
return cppu::supportsService(this, sServiceName);
}
css::uno::Sequence<OUString> ScFilterDetect::getSupportedServiceNames()
{
return { u"com.sun.star.frame.ExtendedTypeDetection"_ustr };
}
extern "C" SAL_DLLPUBLIC_EXPORT css::uno::XInterface*
com_sun_star_comp_calc_FormatDetector_get_implementation(css::uno::XComponentContext* /*context*/,
css::uno::Sequence<css::uno::Any> const &)
{
return cppu::acquire(new ScFilterDetect);
}
/* vim:set shiftwidth=4 softtabstop=4 expandtab: */