fpspreadsheet: Add unit fpsstreams containing a buffered stream for speed-up of writing in virtual mode.

git-svn-id: https://svn.code.sf.net/p/lazarus-ccr/svn@3331 8e941d3f-bd1b-0410-a28a-d453659cc2b4

components/fpspreadsheet/examples/other/test_virtualmode.lpr

@@ -21,6 +21,7 @@ var
   worksheet: TsWorksheet;
   dataprovider: TDataProvider;
   headerTemplate: PCell;
+  t: TTime;
 
   procedure TDataProvider.NeedCellData(Sender: TObject; ARow, ACol: Cardinal;
     var AData: variant; var AStyleCell: PCell);
@@ -33,7 +34,6 @@ var
   }
   var
     s: String;
-    n: Double;
   begin
     if ARow = 0 then begin
       AData := Format('Column %d', [ACol + 1]);
@@ -65,8 +65,8 @@ begin
 
       { These are the essential commands to activate virtual mode: }
 
-      workbook.WritingOptions := [woVirtualMode, woSaveMemory];
+//      workbook.WritingOptions := [woVirtualMode, woSaveMemory];
-//      workbook.WritingOptions := [woVirtualMode];
+      workbook.WritingOptions := [woVirtualMode];
       { woSaveMemory can be omitted, but is essential for large files: it causes
         writing temporaray data to a file stream instead of a memory stream.
         woSaveMemory, however, considerably slows down writing of biff files. }
@@ -74,7 +74,7 @@ begin
       { Next two numbers define the size of virtual spreadsheet.
         In case of a database, VirtualRowCount is the RecordCount, VirtualColCount
         the number of fields to be written to the spreadsheet file }
-      workbook.VirtualRowCount := 10000;
+      workbook.VirtualRowCount := 60000;
       workbook.VirtualColCount := 100;
 
       { The event handler for OnNeedCellData links the workbook to the method
@@ -93,13 +93,17 @@ begin
       worksheet.WriteRowHeight(0, 3);
       worksheet.WriteColWidth(0, 30);
       { In case of a database, you would open the dataset before calling this: }
-      //workbook.WriteToFile('test_virtual.xlsx', sfOOXML, true);
+
-      workbook.WriteToFile('test_virtual.xls', sfExcel8, true);
+      t := Now;
+      workbook.WriteToFile('test_virtual.xlsx', sfOOXML, true);
+      //workbook.WriteToFile('test_virtual.xls', sfExcel8, true);
+      t := Now - t;
 
     finally
       workbook.Free;
     end;
 
+    WriteLn(Format('Execution time: %.3f sec', [t*24*60*60]));
     WriteLn('Press [ENTER] to quit...');
     ReadLn;
   finally

components/fpspreadsheet/fpsstreams.pas

@@ -0,0 +1,199 @@
+unit fpsStreams;
+
+interface
+
+uses
+  SysUtils, Classes;
+
+const
+  DEFAULT_STREAM_BUFFER_SIZE = 1024; // * 1024;
+
+type
+  { A buffered stream }
+  TBufStream = class(TStream)
+  private
+    FFileStream: TFileStream;
+    FMemoryStream: TMemoryStream;
+    FBufWritten: Boolean;
+    FBufSize: Int64;
+    FKeepTmpFile: Boolean;
+    FFileName: String;
+  protected
+    procedure CreateFileStream;
+    function GetPosition: Int64; override;
+    function GetSize: Int64; override;
+  public
+    constructor Create(ATempFile: String; AKeepFile: Boolean = false;
+      ABufSize: Cardinal = DEFAULT_STREAM_BUFFER_SIZE); overload;
+    constructor Create(ABufSize: Cardinal = DEFAULT_STREAM_BUFFER_SIZE); overload;
+    destructor Destroy; override;
+    procedure FlushBuffer;
+    function Read(var Buffer; Count: Longint): Longint; override;
+    function Seek(const Offset: Int64; Origin: TSeekOrigin): Int64; override;
+    function Write(const ABuffer; ACount: Longint): Longint; override;
+  end;
+
+procedure ResetStream(var AStream: TStream);
+
+implementation
+
+uses
+  Math;
+
+{ Resets the stream position to the beginning of the stream. }
+procedure ResetStream(var AStream: TStream);
+begin
+  AStream.Position := 0;
+end;
+
+
+constructor TBufStream.Create(ATempFile: String; AKeepFile: Boolean = false;
+  ABufSize: Cardinal = DEFAULT_STREAM_BUFFER_SIZE);
+begin
+  if ATempFile = '' then
+    ATempFile := ChangeFileExt(GetTempFileName, '.~abc');
+  // Change extension because of naming conflict if the name of the main file
+  // is determined by GetTempFileName also. Happens in internaltests suite.
+  FFileName := ATempFile;
+  FKeepTmpFile := AKeepFile;
+  FMemoryStream := TMemoryStream.Create;
+  // The file stream is only created when needed because of possible conflicts
+  // of random file names.
+  FBufSize := ABufSize;
+end;
+
+constructor TBufStream.Create(ABufSize: Cardinal = DEFAULT_STREAM_BUFFER_SIZE);
+begin
+  Create('', false, ABufSize);
+end;
+
+destructor TBufStream.Destroy;
+begin
+  // Write current buffer content to file
+  FlushBuffer;
+
+  // Free streams and delete temporary file, if requested
+  FreeAndNil(FMemoryStream);
+  FreeAndNil(FFileStream);
+  if not FKeepTmpFile and (FFileName <> '') then DeleteFile(FFileName);
+
+  inherited Destroy;
+end;
+
+{ Creation of the file stream is delayed because of naming conflicts of other
+  streams are needed with random file names as well (the files do not yet exist
+  when the streams are created and therefore get the same name by GetTempFileName! }
+procedure TBufStream.CreateFileStream;
+begin
+  if FFileStream = nil then begin
+    if FFileName = '' then FFileName := ChangeFileExt(GetTempFileName, '.~abc');
+    FFileStream := TFileStream.Create(FFileName, fmCreate + fmOpenRead);
+  end;
+end;
+
+{ Flushes the contents of the memory stream to file }
+procedure TBufStream.FlushBuffer;
+begin
+  if (FMemoryStream.Size > 0) and not FBufWritten then begin
+    FMemoryStream.Position := 0;
+    CreateFileStream;
+    FFileStream.CopyFrom(FMemoryStream, FMemoryStream.Size);
+    FMemoryStream.Clear;
+    FBufWritten := true;
+  end;
+end;
+
+{ Returns the buffer position. This is the buffer position of the bytes written
+  to file, plus the current position in the memory buffer }
+function TBufStream.GetPosition: Int64;
+begin
+  if FFileStream = nil then
+    Result := FMemoryStream.Position
+  else
+    Result := FFileStream.Position + FMemoryStream.Position;
+end;
+
+function TBufStream.GetSize: Int64;
+var
+  n: Int64;
+begin
+  if FFileStream <> nil then
+    n := FFileStream.Size
+  else
+    n := 0;
+  if n = 0 then n := FMemoryStream.Size;
+  Result := Max(n, GetPosition);
+end;
+
+function TBufStream.Read(var Buffer; Count: Longint): Longint;
+begin
+  // Case 1: All "Count" bytes are contained in memory stream
+  if FMemoryStream.Position + Count <= FMemoryStream.Size then begin
+    Result := FMemoryStream.Read(Buffer, Count);
+    exit;
+  end;
+
+  // Case 2: Memory stream is empty
+  if FMemoryStream.Size = 0 then begin
+    CreateFileStream;
+    Result := FFileStream.Read(Buffer, Count);
+    exit;
+  end;
+
+  // Case 3: Memory stream is not empty but contains only part of the bytes requested
+  FlushBuffer;
+  Result := FFileStream.Read(Buffer, Count);
+end;
+
+function TBufStream.Seek(const Offset: Int64; Origin: TSeekOrigin): Int64;
+var
+  oldPos: Int64;
+  newPos: Int64;
+begin
+  oldPos := GetPosition;
+  case Origin of
+    soBeginning : newPos := Offset;
+    soCurrent   : newPos := oldPos + Offset;
+    soEnd       : newPos := GetSize - Offset;
+  end;
+
+  // case #1: New position is within buffer, no file stream yet
+  if (FFileStream = nil) and (newPos < FMemoryStream.Size) then begin
+    FMemoryStream.Position := newPos;
+    exit;
+  end;
+
+  CreateFileStream;
+
+  // case #2: New position is within buffer, file stream exists
+  if (newPos >= FFileStream.Position) and (newPos < FFileStream.Position + FMemoryStream.Size)
+  then begin
+    FMemoryStream.Position := newPos - FFileStream.Position;
+    exit;
+  end;
+
+  // case #3: New position is outside buffer
+  FlushBuffer;
+  FFileStream.Position := newPos;
+end;
+
+function TBufStream.Write(const ABuffer; ACount: LongInt): LongInt;
+var
+  savedPos: Int64;
+begin
+  // Case #1: Bytes fit into buffer
+  if FMemoryStream.Position + ACount < FBufSize then begin
+    Result := FMemoryStream.Write(ABuffer, ACount);
+    FBufWritten := false;
+    exit;
+  end;
+
+  // Case #2: Buffer would overflow
+  savedPos := GetPosition;
+  FlushBuffer;
+  FFileStream.Position := savedPos;
+  Result := FFileStream.Write(ABuffer, ACount);
+end;
+
+
+end.

components/fpspreadsheet/laz_fpspreadsheet.lpk

@@ -18,7 +18,6 @@
       </Parsing>
       <Other>
         <CustomOptions Value="$(IDEBuildOptions)"/>
-        <CompilerPath Value="$(CompPath)"/>
       </Other>
     </CompilerOptions>
     <Description Value="laz_fpspreadsheet is a non-visual component that allows you to use the fpspreadsheet package to read/write spreadsheet files in .xls (BIFF/Excel), .ods OpenDocument (LibreOffice/OpenOffice) and .xlsx Open XML (Excel) formats.
@@ -26,7 +25,7 @@
 This package is all you need if you don't want graphical components (like grids and charts)."/>
     <License Value="LGPL with static linking exception. This is the same license as is used in the LCL (Lazarus Component Library)."/>
     <Version Major="1" Minor="2"/>
-    <Files Count="21">
+    <Files Count="22">
       <Item1>
         <Filename Value="fpolestorage.pas"/>
         <UnitName Value="fpolestorage"/>
@@ -111,6 +110,10 @@ This package is all you need if you don't want graphical components (like grids
         <Filename Value="fpsfunc.pas"/>
         <UnitName Value="fpsfunc"/>
       </Item21>
+      <Item22>
+        <Filename Value="fpsstreams.pas"/>
+        <UnitName Value="fpsStreams"/>
+      </Item22>
     </Files>
     <RequiredPkgs Count="2">
       <Item1>

components/fpspreadsheet/laz_fpspreadsheet.pas

@@ -11,7 +11,7 @@ uses
   xlsbiff5, xlsbiff8, xlsxooxml, fpsutils, fpszipper, uvirtuallayer_types, 
   uvirtuallayer, uvirtuallayer_ole, uvirtuallayer_ole_helpers, 
   uvirtuallayer_ole_types, uvirtuallayer_stream, fpolebasic, xlscommon, 
-  wikitable, fpsNumFormatParser, fpsfunc;
+  wikitable, fpsNumFormatParser, fpsfunc, fpsStreams;
 
 implementation
 

components/fpspreadsheet/tests/internaltests.pas

@@ -17,7 +17,7 @@ uses
   // Instead, add .. to unit search path
   Classes, SysUtils, fpcunit, testutils, testregistry,
   fpsallformats, fpspreadsheet, xlsbiff8 {and a project requirement for lclbase for utf8 handling},
-  fpsutils, testsutility, md5;
+  fpsutils, fpsstreams, testsutility, md5;
 
 type
   { TSpreadReadInternalTests }
@@ -35,6 +35,7 @@ type
     procedure SetUp; override;
     procedure TearDown; override;
     procedure TestVirtualMode(AFormat: TsSpreadsheetFormat; SaveMemoryMode: Boolean);
+
   published
     // Tests getting Excel style A1 cell locations from row/column based locations.
     // Bug 26447
@@ -49,6 +50,8 @@ type
     procedure OverwriteExistingFile;
     // Write out date cell and try to read as UTF8; verify if contents the same
     procedure ReadDateAsUTF8;
+    // Test buffered stream
+    procedure TestBufStream;
 
     // Virtual mode tests for all file formats
     procedure TestVirtualMode_BIFF2;
@@ -172,6 +175,87 @@ begin
   MyWorkbook.Free;
 end;
 
+procedure TSpreadInternalTests.TestBufStream;
+const
+  BUFSIZE = 1024;
+var
+  stream: TBufStream;
+  readBuf, writeBuf1, writeBuf2: array of byte;
+  nRead, nWrite1, nWrite2: Integer;
+  i: Integer;
+begin
+  stream := TBufStream.Create(BUFSIZE);
+  try
+    // Write 100 random bytes. They fit into the BUFSIZE of the memory buffer
+    nWrite1 := 100;
+    SetLength(writeBuf1, nWrite1);
+    for i:=0 to nWrite1-1 do writeBuf1[i] := Random(255);
+    stream.WriteBuffer(writeBuf1[0], nWrite1);
+
+    // Check stream size - must be equal to nWrite
+    CheckEquals(nWrite1, stream.Size, 'Stream size mismatch (#1)');
+
+    // Check stream position must be equal to nWrite
+    CheckEquals(nWrite1, stream.Position, 'Stream position mismatch (#2)');
+
+    // Bring stream pointer back to start
+    stream.Position := 0;
+    CheckEquals(0, stream.Position, 'Stream position mismatch (#3)');
+
+    // Read the first 10 bytes just written and compare
+    nRead := 10;
+    SetLength(readBuf, nRead);
+    nRead := stream.Read(readBuf[0], nRead);
+    CheckEquals(10, nRead, 'Read/write size mismatch (#4)');
+    for i:=0 to 9 do
+      CheckEquals(writeBuf1[i], readBuf[i], Format('Read/write mismatch at position %d (#5)', [i]));
+
+    // Back to start, and read the entire stream
+    stream.Position := 0;
+    nRead := stream.Size;
+    Setlength(readBuf, nRead);
+    nRead := stream.Read(readBuf[0], stream.Size);
+    CheckEquals(nWrite1, nRead, 'Stream read size mismatch (#6)');
+    for i:=0 to nWrite1-1 do
+      CheckEquals(writeBuf1[i], readBuf[i], Format('Read/write mismatch at position %d (#7)', [i]));
+
+    // Now put stream pointer to end and write another 2000 bytes. This crosses
+    // the size of the memory buffer, and the stream must swap to file.
+    stream.Seek(0, soFromEnd);
+    CheckEquals(stream.Size, stream.Position, 'Stream position not at end (#8)');
+
+    nWrite2 := 2000;
+    SetLength(writeBuf2, nWrite2);
+    for i:=0 to nWrite2-1 do writeBuf2[i] := Random(255);
+    stream.WriteBuffer(writeBuf2[0], nWrite2);
+
+    // The stream pointer must be at 100+2000, same for the size
+    CheckEquals(nWrite1+nWrite2, stream.Position, 'Stream position mismatch (#9)');
+    CheckEquals(nWrite1+nWrite2, stream.Size, 'Stream size mismatch (#10)');
+
+    // Read the last 10 bytes and compare
+    Stream.Seek(10, soFromEnd);
+    SetLength(readBuf, 10);
+    Stream.ReadBuffer(readBuf[0], 10);
+    for i:=0 to 9 do
+      CheckEquals(writeBuf2[nWrite2-10+i], readBuf[i], Format('Read/write mismatch at position %d from end (#11)', [i]));
+
+    // Now read all from beginning
+    Stream.Position := 0;
+    SetLength(readBuf, stream.Size);
+    nRead := Stream.Read(readBuf[0], stream.Size);
+    CheckEquals(nWrite1+nWrite2, nRead, 'Read/write size mismatch (#4)');
+    for i:=0 to nRead-1 do
+      if i < nWrite1 then
+        CheckEquals(writeBuf1[i], readBuf[i], Format('Read/write mismatch at position %d (#11)', [i]))
+      else
+        CheckEquals(writeBuf2[i-nWrite1], readBuf[i], Format('Read/write mismatch at position %d (#11)', [i]));
+
+  finally
+    stream.Free;
+  end;
+end;
+
 procedure TSpreadInternalTests.TestCellString;
 var
   r,c: Cardinal;

components/fpspreadsheet/xlsbiff8.pas

@@ -220,6 +220,9 @@ var
 
 implementation
 
+uses
+  fpsStreams;
+
 const
   { Excel record IDs }
   INT_EXCEL_ID_SST        = $00FC; //BIFF8 only
@@ -361,12 +364,9 @@ var
   Stream: TStream;
   OutputStorage: TOLEStorage;
   OLEDocument: TOLEDocument;
-  fn: String;
 begin
   if (woSaveMemory in Workbook.WritingOptions) then begin
-    fn := GetTempFileName('', 'fpsB8');
+    Stream := TBufStream.Create
-    if FileExists(fn) then DeleteFile(fn);
-    Stream := TFileStream.Create(fn, fmCreate + fmOpenRead)
   end else
     Stream := TMemoryStream.Create;
 
@@ -379,8 +379,6 @@ begin
 
     OutputStorage.WriteOLEFile(AFileName, OLEDocument, AOverwriteExisting, 'Workbook');
   finally
-    if (woSaveMemory in Workbook.WritingOptions) then
-      DeleteFile(fn);
     Stream.Free;
     OutputStorage.Free;
   end;

components/fpspreadsheet/xlscommon.pas

@@ -505,12 +505,12 @@ type
     procedure WriteSelections(AStream: TStream; ASheet: TsWorksheet);
     procedure WriteSheetPR(AStream: TStream);
     procedure WriteStringRecord(AStream: TStream; AString: String); virtual;
+    // Writes cell content received by workbook in OnNeedCellData event
+    procedure WriteVirtualCells(AStream: TStream);
     // Writes out a WINDOW1 record
     procedure WriteWindow1(AStream: TStream); virtual;
     // Writes the index of the XF record used in the given cell
     procedure WriteXFIndex(AStream: TStream; ACell: PCell);
-    // Writes cell content received by workbook in OnNeedCellData event
-    procedure WriteVirtualCells(AStream: TStream);
 
   public
     constructor Create(AWorkbook: TsWorkbook); override;
@@ -2568,6 +2568,49 @@ begin
   Unused(AStream, AString);
 end;
 
+procedure TsSpreadBIFFWriter.WriteVirtualCells(AStream: TStream);
+var
+  r,c: Cardinal;
+  lCell: TCell;
+  value: variant;
+  styleCell: PCell;
+begin
+  for r := 0 to Workbook.VirtualRowCount-1 do begin
+    for c := 0 to Workbook.VirtualColCount-1 do begin
+      FillChar(lCell, SizeOf(lCell), 0);
+      value := varNull;
+      styleCell := nil;
+      Workbook.OnNeedCellData(Workbook, r, c, value, styleCell);
+      if styleCell <> nil then lCell := styleCell^;
+      lCell.Row := r;
+      lCell.Col := c;
+      if VarIsNull(value) then
+        lCell.ContentType := cctEmpty
+      else
+      if VarIsNumeric(value) then begin
+        lCell.ContentType := cctNumber;
+        lCell.NumberValue := value;
+      end else
+      {
+      if VarIsDateTime(value) then begin
+        lCell.ContentType := cctNumber;
+        lCell.DateTimeValue := value;
+      end else
+      }
+      if VarIsStr(value) then begin
+        lCell.ContentType := cctUTF8String;
+        lCell.UTF8StringValue := VarToStrDef(value, '');
+      end else
+      if VarIsBool(value) then begin
+        lCell.ContentType := cctBool;
+        lCell.BoolValue := value <> 0;
+      end else
+        lCell.ContentType := cctEmpty;
+      WriteCellCallback(@lCell, AStream);
+    end;
+  end;
+end;
+
 { Writes an Excel 5/8 WINDOW1 record
   This record contains general settings for the document window and
   global workbook settings.
@@ -2642,48 +2685,5 @@ begin
   AStream.WriteWord(WordToLE(lXFIndex));
 end;
 
-procedure TsSpreadBIFFWriter.WriteVirtualCells(AStream: TStream);
-var
-  r,c: Cardinal;
-  lCell: TCell;
-  value: variant;
-  styleCell: PCell;
-begin
-  for r := 0 to Workbook.VirtualRowCount-1 do begin
-    for c := 0 to Workbook.VirtualColCount-1 do begin
-      FillChar(lCell, SizeOf(lCell), 0);
-      value := varNull;
-      styleCell := nil;
-      Workbook.OnNeedCellData(Workbook, r, c, value, styleCell);
-      if styleCell <> nil then lCell := styleCell^;
-      lCell.Row := r;
-      lCell.Col := c;
-      if VarIsNull(value) then
-        lCell.ContentType := cctEmpty
-      else
-      if VarIsNumeric(value) then begin
-        lCell.ContentType := cctNumber;
-        lCell.NumberValue := value;
-      end else
-      {
-      if VarIsDateTime(value) then begin
-        lCell.ContentType := cctNumber;
-        lCell.DateTimeValue := value;
-      end else
-      }
-      if VarIsStr(value) then begin
-        lCell.ContentType := cctUTF8String;
-        lCell.UTF8StringValue := VarToStrDef(value, '');
-      end else
-      if VarIsBool(value) then begin
-        lCell.ContentType := cctBool;
-        lCell.BoolValue := value <> 0;
-      end else
-        lCell.ContentType := cctEmpty;
-      WriteCellCallback(@lCell, AStream);
-    end;
-  end;
-end;
-
 end.
 

components/fpspreadsheet/xlsxooxml.pas

@@ -115,7 +115,7 @@ type
 implementation
 
 uses
-  variants, fpsNumFormatParser, xlscommon;
+  variants, fpsStreams, fpsNumFormatParser, xlscommon;
 
 const
   { OOXML general XML constants }
@@ -737,16 +737,16 @@ begin
 
   // Style records
   AppendToStream(FSStyles,
-      '<cellStyleXfs count="1">',
+      '<cellStyleXfs count="1">' +
-        '<xf numFmtId="0" fontId="0" fillId="0" borderId="0" />',
+        '<xf numFmtId="0" fontId="0" fillId="0" borderId="0" />' +
       '</cellStyleXfs>'
   );
   WriteStyleList(FSStyles, 'cellXfs');
 
   // Cell style records
   AppendToStream(FSStyles,
-      '<cellStyles count="1">',
+      '<cellStyles count="1">' +
-        '<cellStyle name="Normal" xfId="0" builtinId="0" />',
+        '<cellStyle name="Normal" xfId="0" builtinId="0" />' +
       '</cellStyles>');
 
   // Misc
@@ -779,7 +779,7 @@ begin
       '<Relationship Type="%s" Target="worksheets/sheet%d.xml" Id="rId%d" />',
         [SCHEMAS_WORKSHEET, i, i+2]));
 
-  AppendToStream(FSWOrkbookRels,
+  AppendToStream(FSWorkbookRels,
     '</Relationships>');
 
   { --- Workbook --- }
@@ -820,11 +820,10 @@ begin
     XML_HEADER, Format(
     '<sst xmlns="%s" count="%d" uniqueCount="%d">', [SCHEMAS_SPREADML, FSharedStringsCount, FSharedStringsCount]
   ));
-  FSSharedStrings.Position := 0;
+  ResetStream(FSSharedStrings);
   FSSharedStrings_complete.CopyFrom(FSSharedStrings, FSSharedStrings.Size);
   AppendToStream(FSSharedStrings_complete,
     '</sst>');
-  FSSharedStrings_complete.Position := 0;
 end;
 
 {
@@ -875,7 +874,6 @@ var
   CellPosText: string;
   value: Variant;
   styleCell: PCell;
-  fn: String;
   row: PRow;
   rh: String;
   h0: Single;
@@ -885,11 +883,9 @@ begin
   h0 := Workbook.GetDefaultFontSize;  // Point size of default font
 
   // Create the stream
-  if (woSaveMemory in Workbook.WritingOptions) then begin
+  if (woSaveMemory in Workbook.WritingOptions) then
-    fn := IncludeTrailingPathDelimiter(GetTempDir);
+    FSSheets[FCurSheetNum] := TBufStream.Create(GetTempFileName('', Format('fpsSH%d', [FCurSheetNum])))
-    fn := GetTempFileName(fn, Format('fpsSH%d-', [FCurSheetNum+1]));
+  else
-    FSSheets[FCurSheetNum] := TFileStream.Create(fn, fmCreate);
-  end else
     FSSheets[FCurSheetNum] := TMemoryStream.Create;
 
   // Header
@@ -1016,18 +1012,15 @@ end;
 { Creates the streams for the individual data files. Will be zipped into a
   single xlsx file. }
 procedure TsSpreadOOXMLWriter.CreateStreams;
-var
-  dir: String;
 begin
   if (woSaveMemory in Workbook.WritingOptions) then begin
-    dir := IncludeTrailingPathDelimiter(GetTempDir);
+    FSContentTypes := TBufStream.Create(GetTempFileName('', 'fpsCT'));
-    FSContentTypes := TFileStream.Create(GetTempFileName(dir, 'fpsCT'), fmCreate+fmOpenRead);
+    FSRelsRels := TBufStream.Create(GetTempFileName('', 'fpsRR'));
-    FSRelsRels := TFileStream.Create(GetTempFileName(dir, 'fpsRR'), fmCreate+fmOpenRead);
+    FSWorkbookRels := TBufStream.Create(GetTempFileName('', 'fpsWBR'));
-    FSWorkbookRels := TFileStream.Create(GetTempFileName(dir, 'fpsWBR'), fmCreate+fmOpenRead);
+    FSWorkbook := TBufStream.Create(GetTempFileName('', 'fpsWB'));
-    FSWorkbook := TFileStream.Create(GetTempFileName(dir, 'fpsWB'), fmCreate+fmOpenRead);
+    FSStyles := TBufStream.Create(GetTempFileName('', 'fpsSTY'));
-    FSStyles := TFileStream.Create(GetTempFileName(dir, 'fpsSTY'), fmCreate+fmOpenRead);
+    FSSharedStrings := TBufStream.Create(GetTempFileName('', 'fpsSS'));
-    FSSharedStrings := TFileStream.Create(GetTempFileName(dir, 'fpsSST'), fmCreate+fmOpenRead);
+    FSSharedStrings_complete := TBufStream.Create(GetTempFileName('', 'fpsSSC'));
-    FSSharedStrings_complete := TFileStream.Create(GetTempFileName(dir, 'fpsSSTc'), fmCreate+fmOpenRead);
   end else begin;
     FSContentTypes := TMemoryStream.Create;
     FSRelsRels := TMemoryStream.Create;
@@ -1072,7 +1065,17 @@ end;
 procedure TsSpreadOOXMLWriter.ResetStreams;
 var
   stream: TStream;
+  i: Integer;
 begin
+  ResetStream(FSContentTypes);
+  ResetStream(FSRelsRels);
+  ResetStream(FSWorkbookRels);
+  ResetStream(FSWorkbook);
+  ResetStream(FSStyles);
+  ResetStream(FSSharedStrings_complete);
+  for i := 0 to High(FSSheets) do
+    ResetStream(FSSheets[i]);
+    {
   FSContentTypes.Position := 0;
   FSRelsRels.Position := 0;
   FSWorkbookRels.Position := 0;
@@ -1080,6 +1083,7 @@ begin
   FSStyles.Position := 0;
   FSSharedStrings_complete.Position := 0;
   for stream in FSSheets do stream.Position := 0;
+  }
 end;
 
 {
@@ -1135,9 +1139,13 @@ begin
   WriteGlobalFiles;
   WriteContent;
 
+  // Stream position must be at beginning, it was moved to end during adding of xml strings.
+  ResetStreams;
+
   { Now compress the files }
   FZip := TZipper.Create;
   try
+    FZip.FileName := '__temp__.tmp';
     FZip.Entries.AddFileEntry(FSContentTypes, OOXML_PATH_TYPES);
     FZip.Entries.AddFileEntry(FSRelsRels, OOXML_PATH_RELS_RELS);
     FZip.Entries.AddFileEntry(FSWorkbookRels, OOXML_PATH_XL_RELS_RELS);
@@ -1150,9 +1158,6 @@ begin
       FZip.Entries.AddFileEntry(FSSheets[i], OOXML_PATH_XL_WORKSHEETS + 'sheet' + IntToStr(i + 1) + '.xml');
     end;
 
-    // Stream position must be at beginning, it was moved to end during adding of xml strings.
-    ResetStreams;
-
     FZip.SaveToStream(AStream);
 
   finally