fpspreadsheet: Write unzipped xml files of xlsx and ods to a unique temp directory.

git-svn-id: https://svn.code.sf.net/p/lazarus-ccr/svn@4310 8e941d3f-bd1b-0410-a28a-d453659cc2b4

components/fpspreadsheet/fpsopendocument.pas

@@ -2054,7 +2054,7 @@ var
   sheet: TsWorksheet;
 begin
   //unzip files into AFileName path
-  FilePath := GetTempDir(false);
+  FilePath := GetUniqueTempDir(false);
   UnZip := TUnZipper.Create;
   FileList := TStringList.Create;
   try
@@ -2155,6 +2155,7 @@ begin
     FWorkbook.SelectWorksheet(sheet);
 
   finally
+    RemoveDir(FilePath);
     if Assigned(Doc) then Doc.Free;
   end;
 end;

components/fpspreadsheet/fpsutils.pas

@@ -150,6 +150,8 @@ function HasFormula(ACell: PCell): Boolean;
 function SameCellBorders(AFormat1, AFormat2: PsCellFormat): Boolean;
 function SameFont(AFont1, AFont2: TsFont): Boolean;
 
+function GetUniqueTempDir(Global: Boolean): String;
+
 procedure AppendToStream(AStream: TStream; const AString: String); inline; overload;
 procedure AppendToStream(AStream: TStream; const AString1, AString2: String); inline; overload;
 procedure AppendToStream(AStream: TStream; const AString1, AString2, AString3: String); inline; overload;
@@ -170,7 +172,7 @@ var
 implementation
 
 uses
-  Math, lazutf8, fpsStrings;
+  Math, lazutf8, lazfileutils, fpsStrings;
 
 {******************************************************************************}
 {                       Endianess helper functions                             }
@@ -1934,6 +1936,29 @@ begin
     Result := true;
 end;
 
+{@@ ----------------------------------------------------------------------------
+  Constructs a string of length "Len" containing random uppercase characters
+-------------------------------------------------------------------------------}
+function GetRandomString(Len: Integer): String;
+begin
+  Result := '';
+  While Length(Result) < Len do
+    Result := Result + char(ord('A') + random(26));
+end;
+
+{@@ ----------------------------------------------------------------------------
+  Constructs a unique folder name in the temp directory of the OS
+-------------------------------------------------------------------------------}
+function GetUniqueTempDir(Global: Boolean): String;
+var
+  tempdir: String;
+begin
+  tempdir := AppendPathDelim(GetTempDir(Global));
+  repeat
+    Result := tempdir + AppendPathDelim(GetRandomString(8));
+  until not DirectoryExists(Result);
+end;
+
 {@@ ----------------------------------------------------------------------------
   Appends a string to a stream
 

components/fpspreadsheet/xlsxooxml.pas

@@ -1902,7 +1902,7 @@ var
   actSheetIndex: Integer;
 begin
   //unzip "content.xml" of "AFileName" to folder "FilePath"
-  FilePath := GetTempDir(false);
+  FilePath := GetUniqueTempDir(false);
   UnZip := TUnZipper.Create;
   FileList := TStringList.Create;
   try
@@ -2029,6 +2029,7 @@ begin
     end;  // for
 
   finally
+    RemoveDir(FilePath);
     SheetList.Free;
     FreeAndNil(Doc);
   end;