fpspreadsheet: Fix crash when reading a BIFF5 file written by Excel97 (it has data (the directory) beyound the workbook stream which is not expected by the BIFF5/8 readers).

git-svn-id: https://svn.code.sf.net/p/lazarus-ccr/svn@3897 8e941d3f-bd1b-0410-a28a-d453659cc2b4

components/fpspreadsheet/examples/fpsctrls/demo_ctrls.lpi

@@ -67,7 +67,7 @@
       <Unit1>
         <Filename Value="main.pas"/>
         <IsPartOfProject Value="True"/>
-        <ComponentName Value="Form1"/>
+        <ComponentName Value="MainForm"/>
         <HasResources Value="True"/>
         <ResourceBaseClass Value="Form"/>
         <UnitName Value="main"/>

components/fpspreadsheet/examples/fpsctrls/demo_ctrls.lpr

@@ -15,7 +15,7 @@ uses
 begin
   RequireDerivedFormResource := True;
   Application.Initialize;
-  Application.CreateForm(TForm1, Form1);
+  Application.CreateForm(TMainForm, MainForm);
   Application.Run;
 end.
 

components/fpspreadsheet/examples/fpsctrls/main.lfm

@@ -1,9 +1,9 @@
-object Form1: TForm1
+object MainForm: TMainForm
   Left = 495
   Height = 600
   Top = 132
   Width = 929
-  Caption = 'Form1'
+  Caption = 'demo_ctrls'
   ClientHeight = 580
   ClientWidth = 929
   Menu = MainMenu

components/fpspreadsheet/examples/fpsctrls/main.pas

@@ -11,9 +11,9 @@ uses
 
 type
 
-  { TForm1 }
+  { TMainForm }
 
-  TForm1 = class(TForm)
+  TMainForm = class(TForm)
     AcRowDelete: TAction;
     AcColDelete: TAction;
     AcRowAdd: TAction;
@@ -286,21 +286,22 @@ type
     procedure InspectorTabControlChange(Sender: TObject);
   private
     { private declarations }
+    procedure UpdateCaption;
   public
     { public declarations }
   end;
 
 var
-  Form1: TForm1;
+  MainForm: TMainForm;
 
 implementation
 
 {$R *.lfm}
 
-{ TForm1 }
+{ TMainForm }
 
 { Loads the spreadsheet file selected by the AcFileOpen action }
-procedure TForm1.AcFileOpenAccept(Sender: TObject);
+procedure TMainForm.AcFileOpenAccept(Sender: TObject);
 begin
   WorkbookSource.AutodetectFormat := false;
   case AcFileOpen.Dialog.FilterIndex of
@@ -314,10 +315,11 @@ begin
     8: WorkbookSource.FileFormat := sfCSV;           // Text files
   end;
   WorkbookSource.FileName := AcFileOpen.Dialog.FileName;  // this loads the file
+  UpdateCaption;
 end;
 
 { Saves the spreadsheet to the file selected by the AcFileSaveAs action }
-procedure TForm1.AcFileSaveAsAccept(Sender: TObject);
+procedure TMainForm.AcFileSaveAsAccept(Sender: TObject);
 var
   fmt: TsSpreadsheetFormat;
 begin
@@ -333,20 +335,21 @@ begin
       7: fmt := sfWikiTable_WikiMedia;
     end;
     WorkbookSource.SaveToSpreadsheetFile(AcFileSaveAs.Dialog.FileName, fmt);
+    UpdateCaption;
   finally
     Screen.Cursor := crDefault;
   end;
 end;
 
 { Adds a column before the active cell }
-procedure TForm1.AcColAddExecute(Sender: TObject);
+procedure TMainForm.AcColAddExecute(Sender: TObject);
 begin
   WorksheetGrid.InsertCol(WorksheetGrid.Col);
   WorksheetGrid.Col := WorksheetGrid.Col + 1;
 end;
 
 { Deletes the column with the active cell }
-procedure TForm1.AcColDeleteExecute(Sender: TObject);
+procedure TMainForm.AcColDeleteExecute(Sender: TObject);
 var
   c: Integer;
 begin
@@ -356,14 +359,14 @@ begin
 end;
 
 { Adds a row before the active cell }
-procedure TForm1.AcRowAddExecute(Sender: TObject);
+procedure TMainForm.AcRowAddExecute(Sender: TObject);
 begin
   WorksheetGrid.InsertRow(WorksheetGrid.Row);
   WorksheetGrid.Row := WorksheetGrid.Row + 1;
 end;
 
 { Deletes the row with the active cell }
-procedure TForm1.AcRowDeleteExecute(Sender: TObject);
+procedure TMainForm.AcRowDeleteExecute(Sender: TObject);
 var
   r: Integer;
 begin
@@ -373,17 +376,28 @@ begin
 end;
 
 { Toggles the spreadsheet inspector on and off }
-procedure TForm1.AcViewInspectorExecute(Sender: TObject);
+procedure TMainForm.AcViewInspectorExecute(Sender: TObject);
 begin
   InspectorTabControl.Visible := AcViewInspector.Checked;
 end;
 
 { Event handler to synchronize the mode of the spreadsheet inspector with the
   selected tab of the TabControl }
-procedure TForm1.InspectorTabControlChange(Sender: TObject);
+procedure TMainForm.InspectorTabControlChange(Sender: TObject);
 begin
   Inspector.Mode := TsInspectorMode(InspectorTabControl.TabIndex);
 end;
 
+procedure TMainForm.UpdateCaption;
+begin
+  if WorkbookSource = nil then
+    Caption := 'demo_ctrls'
+  else
+    Caption := Format('demo_ctrls - "%s" [%s]', [
+      WorkbookSource.Filename,
+      GetFileFormatName(WorkbookSource.Workbook.FileFormat)
+    ]);
+end;
+
 end.
 

components/fpspreadsheet/fpspreadsheet.pas

@@ -6399,8 +6399,8 @@ class function TsWorkbook.GetFormatFromFileHeader(const AFileName: TFileName;
 const
   BIFF2_HEADER: array[0..15] of byte = (
     $09,$00, $04,$00, $00,$00, $10,$00, $31,$00, $0A,$00, $C8,$00, $00,$00);
-  BIFF58_HEADER: array[0..15] of byte = (
+  BIFF58_HEADER: array[0..7] of byte = (
-    $D0,$CF, $11,$E0, $A1,$B1, $1A,$E1, $00,$00, $00,$00, $00,$00, $00,$00);
+    $D0,$CF, $11,$E0, $A1,$B1, $1A,$E1);
   BIFF5_MARKER: array[0..7] of widechar = (
     'B', 'o', 'o', 'k', #0, #0, #0, #0);
   BIFF8_MARKER:array[0..7] of widechar = (
@@ -6419,7 +6419,7 @@ begin
     // Read first 16 bytes
     stream.ReadBuffer(buf, 16);
 
-    // Check for Excel 2#
+    // Check for Excel 2
     ok := true;
     for i:=0 to 15 do
       if buf[i] <> BIFF2_HEADER[i] then
@@ -6434,7 +6434,7 @@ begin
     end;
 
     // Check for Excel 5 or 8
-    for i:=0 to 15 do
+    for i:=0 to 7 do
       if buf[i] <> BIFF58_HEADER[i] then
         exit;
 

components/fpspreadsheet/xlsbiff5.pas

@@ -387,7 +387,6 @@ begin
     CurStreamPos := AStream.Position;
 
     case RecordType of
-
       INT_EXCEL_ID_BLANK         : ReadBlank(AStream);
       INT_EXCEL_ID_BOOLERROR     : ReadBool(AStream);
       INT_EXCEL_ID_MULBLANK      : ReadMulBlank(AStream);
@@ -720,6 +719,7 @@ end;
 procedure TsSpreadBIFF5Reader.ReadFromStream(AStream: TStream; AData: TsWorkbook);
 var
   BIFF5EOF: Boolean;
+  p,s: Int64;
 begin
   { Initializations }
 
@@ -742,10 +742,15 @@ begin
     ReadWorksheet(AStream, AData);
 
     // Check for the end of the file
+    p := AStream.Position;
+    s := AStream.Size;
     if AStream.Position >= AStream.Size then BIFF5EOF := True;
 
     // Final preparations
     Inc(FCurrentWorksheet);
+    if FCurrentWorksheet = FWorksheetNames.Count then BIFF5EOF := True;
+    // It can happen in files written by Office97 that the OLE directory is
+    // at the end of the file.
   end;
 
   if not FPaletteFound then

components/fpspreadsheet/xlsbiff8.pas

@@ -638,6 +638,9 @@ begin
 
     // Final preparations
     Inc(FCurrentWorksheet);
+    if FCurrentWorksheet = FWorksheetNames.Count then BIFF8EOF := True;
+    // It can happen in files written by Office97 that the OLE directory is
+    // at the end of the file.
   end;
 
   if not FPaletteFound then