Fixes incorrect save NUMBER value to DBF (fdo#30504)

Open Office Calc save numeric value in numeric column as text
representation add null chars right for column with.
Bat other applications save value as text and space chars left for
column with.

For example:
Format: N, 3, 0
Value: 1
Calc saved value (hex): 31 00 00
Other Apps saved value (hex): 20 20 31

This inaccuracy does not affect the format of the readers implemented in
C or C++ but can break the implementation in other languages (Python,
Ruby, Haskell)

connectivity/source/drivers/dbase/DTable.cxx

@@ -1780,7 +1780,7 @@ BOOL ODbaseTable::UpdateBuffer(OValueRefVector& rRow, OValueRefRow pOrgRow,const
 
     for (i = 0; i < nColumnCount && nByteOffset <= m_nBufferSize ; ++i)
     {
-        // Laengen je nach Datentyp:
+        // Lengths for each data type:
         OSL_ENSURE(i < m_aPrecisions.size(),"Illegal index!");
         sal_Int32 nLen = 0;
         sal_Int32 nType = 0;
@@ -1817,7 +1817,7 @@ BOOL ODbaseTable::UpdateBuffer(OValueRefVector& rRow, OValueRefRow pOrgRow,const
                 break;
             case DataType::DECIMAL:
                 nLen = SvDbaseConverter::ConvertPrecisionToDbase(nLen,nScale);
-                break;  // das Vorzeichen und das Komma
+                break;  // The sign and the comma
             default:
                 break;
 
@@ -1846,10 +1846,10 @@ BOOL ODbaseTable::UpdateBuffer(OValueRefVector& rRow, OValueRefRow pOrgRow,const
 
 
         ++nPos; // the row values start at 1
-        // Ist die Variable ueberhaupt gebunden?
+        // If the variable is bound at all?
         if ( !rRow.get()[nPos]->isBound() )
         {
-            // Nein - naechstes Feld.
+            // No - the next field.
             nByteOffset += nLen;
             continue;
         }
@@ -1870,15 +1870,14 @@ BOOL ODbaseTable::UpdateBuffer(OValueRefVector& rRow, OValueRefRow pOrgRow,const
         if (rRow.get()[nPos]->getValue().isNull())
         {
             if ( bSetZero )
-                memset(pData,0,nLen);   // Zuruecksetzen auf NULL
+                memset(pData,0,nLen);   // Clear to NULL
             else
-                memset(pData,' ',nLen); // Zuruecksetzen auf NULL
+                memset(pData,' ',nLen); // Clear to NULL
             nByteOffset += nLen;
             OSL_ENSURE( nByteOffset <= m_nBufferSize ,"ByteOffset > m_nBufferSize!");
             continue;
         }
 
-        sal_Bool bHadError = sal_False;
         try
         {
             switch (nType)
@@ -1887,7 +1886,7 @@ BOOL ODbaseTable::UpdateBuffer(OValueRefVector& rRow, OValueRefRow pOrgRow,const
                     {
                         sal_Int32 nJulianDate = 0, nJulianTime = 0;
                         lcl_CalcJulDate(nJulianDate,nJulianTime,rRow.get()[nPos]->getValue());
-                        // Genau 8 Byte kopieren:
+                        // Exactly 8 bytes to copy:
                         memcpy(pData,&nJulianDate,4);
                         memcpy(pData+4,&nJulianTime,4);
                     }
@@ -1907,7 +1906,7 @@ BOOL ODbaseTable::UpdateBuffer(OValueRefVector& rRow, OValueRefRow pOrgRow,const
                         (int)aDate.Month,
                         (int)aDate.Day);
 
-                    // Genau 8 Byte kopieren:
+                    // Exactly 8 bytes to copy:
                     strncpy(pData,s,sizeof s - 1);
                 } break;
                 case DataType::INTEGER:
@@ -1936,18 +1935,18 @@ BOOL ODbaseTable::UpdateBuffer(OValueRefVector& rRow, OValueRefRow pOrgRow,const
                     break;
                 case DataType::DECIMAL:
                 {
-                    memset(pData,' ',nLen); // Zuruecksetzen auf NULL
+                    memset(pData,' ',nLen); // Clear to NULL
 
                     const double n = rRow.get()[nPos]->getValue();
 
-                    // ein const_cast, da GetFormatPrecision am SvNumberFormat nicht const ist, obwohl es das eigentlich
-                    // sein koennte und muesste
-
+                    // one, because const_cast GetFormatPrecision on SvNumberFormat is not constant,
+                    // even though it really could and should be
                     const ByteString aDefaultValue( ::rtl::math::doubleToString( n, rtl_math_StringFormat_F, nScale, '.', NULL, 0));
-                    BOOL bValidLength  = aDefaultValue.Len() <= nLen;
-                    if ( bValidLength )
+                    const sal_Int32 nValueLen = aDefaultValue.Len();
+                    if ( nValueLen <= nLen )
                     {
-                        strncpy(pData,aDefaultValue.GetBuffer(),nLen);
+                        // Write value right-justified, padded with blanks to the left.
+                        memcpy(pData+nLen-nValueLen,aDefaultValue.GetBuffer(),nValueLen);
                         // write the resulting double back
                         *rRow.get()[nPos] = toDouble(aDefaultValue);
                     }
@@ -1975,12 +1974,12 @@ BOOL ODbaseTable::UpdateBuffer(OValueRefVector& rRow, OValueRefRow pOrgRow,const
                 case DataType::LONGVARBINARY:
                 case DataType::LONGVARCHAR:
                 {
-                    char cNext = pData[nLen]; // merken und temporaer durch 0 ersetzen
-                    pData[nLen] = '\0';       // das geht, da der Puffer immer ein Zeichen groesser ist ...
+                    char cNext = pData[nLen]; // Mark's scratch and replaced by 0
+                    pData[nLen] = '\0';       // This is because the buffer is always a sign of greater ...
 
-                    ULONG nBlockNo = strtol((const char *)pData,NULL,10);   // Blocknummer lesen
+                    ULONG nBlockNo = strtol((const char *)pData,NULL,10);   // Block number read
 
-                    // Naechstes Anfangszeichen wieder restaurieren:
+                    // Next initial character restore again:
                     pData[nLen] = cNext;
                     if (!m_pMemoStream || !WriteMemo(rRow.get()[nPos]->get(), nBlockNo))
                         break;
@@ -1989,13 +1988,13 @@ BOOL ODbaseTable::UpdateBuffer(OValueRefVector& rRow, OValueRefRow pOrgRow,const
                     ByteString aBlock(ByteString::CreateFromInt32(nBlockNo));
                     aStr.Expand(static_cast<sal_uInt16>(nLen - aBlock.Len()), '0' );
                     aStr += aBlock;
-                    // Zeichen kopieren:
-                    memset(pData,' ',nLen); // Zuruecksetzen auf NULL
+                    // Copy characters:
+                    memset(pData,' ',nLen); // Clear to NULL
                     memcpy(pData, aStr.GetBuffer(), nLen);
                 }   break;
                 default:
                 {
-                    memset(pData,' ',nLen); // Zuruecksetzen auf NULL
+                    memset(pData,' ',nLen); // Clear to NULL
 
                     ::rtl::OUString sStringToWrite( rRow.get()[nPos]->getValue().getString() );
 
@@ -2013,9 +2012,7 @@ BOOL ODbaseTable::UpdateBuffer(OValueRefVector& rRow, OValueRefRow pOrgRow,const
         {
             throw;
         }
-        catch ( Exception& ) { bHadError = sal_True; }
-
-        if ( bHadError )
+        catch ( Exception& )
         {
             m_pColumns->getByIndex(i) >>= xCol;
             OSL_ENSURE( xCol.is(), "ODbaseTable::UpdateBuffer column is null!" );
@@ -2028,7 +2025,7 @@ BOOL ODbaseTable::UpdateBuffer(OValueRefVector& rRow, OValueRefRow pOrgRow,const
                  ) );
             ::dbtools::throwGenericSQLException( sError, *this );
         }
-        // Und weiter ...
+        // And more ...
         nByteOffset += nLen;
         OSL_ENSURE( nByteOffset <= m_nBufferSize ,"ByteOffset > m_nBufferSize!");
     }