CreateFile + VirtualAlloc -> Datei kopieren (geht/nicht)

[himitsu]

Delphi-Quellcode:

if ( hDestFile = INVALID_HANDLE_VALUE ) then
begin
  CloseHandle( hSrcFile );
  DoNotifyError( SysErrorMessage( GetLastError ) );   
  Exit;
end;

PS: hSrcFile ist und bleibt bei einem Fehler hier ebenfalls geöffnet

Eine Lösung wäre zwar sowas, aber übersichtlich ist's nicht gerade.

Delphi-Quellcode:

hSrcFile := CreateFile( PAnsiChar(aSrcFile), GENERIC_READ, FILE_SHARE_READ, nil, OPEN_EXISTING, 0, 0 );
if ( hSrcFile = INVALID_HANDLE_VALUE ) then
begin
  DoNotifyError( SysErrorMessage( GetLastError ) );
  Exit;
end;

hDestFile := CreateFile( PAnsiChar(aDestFile), GENERIC_WRITE, FILE_SHARE_READ, nil, CREATE_ALWAYS, 0, 0 );
if ( hDestFile = INVALID_HANDLE_VALUE ) then
begin
  CloseHandle(hSrcFile);  // <<<<<<<<<<<<<<<<<<<<<
  CloseHandle( hSrcFile );
  DoNotifyError( SysErrorMessage( GetLastError ) );   
  Exit;
end;

Size := ( UpSize shl 16 or LoSize ); Cardinal ist 32 Bit.

if ( Size.QuadPart > 0 ) then Schau dir bitte dringend mal die Definition der Rückgabewerte an!
> GetFileSize


Mein Weg sähe wohl etwa so aus:

Delphi-Quellcode:

var
  Size     : LARGE_INTEGER;
  Read     ,
  Written  ,
  GLE      : Cardinal;
  IO       : Pointer;
  hSrcFile ,
  hDestFile: THandle;
begin
  Result       := False;
  hSrcFile     := CreateFile( PAnsiChar(aSrcFile), 
                    GENERIC_READ, FILE_SHARE_READ, nil, OPEN_EXISTING, 0, 0 );
  hDestFile    := CreateFile( PAnsiChar(aDestFile),
                    GENERIC_WRITE, FILE_SHARE_READ, nil, CREATE_ALWAYS, 0, 0 );
  Size.LowPart := GetFileSize( hSrcFile, @Size.HighPart);
  GLE          := GetLastError;
  IO           := VirtualAlloc( nil, 2048, MEM_COMMIT, PAGE_READWRITE );

  if ( hSrcFile <> INVALID_HANDLE_VALUE ) 
    and ( hDestFile <> INVALID_HANDLE_VALUE ) 
    and (( Size.QuadPart <> $ffffffff ) or (GLE = NO_ERROR))
    and Assigned( IO ) then
  begin
    Result  := True;
    Read    := 0;
    Written := 0;
   
    while ( Result and ( Read = Written ) and ( Size > 0 ) ) do
    begin
      Result := ReadFile( hSrcFile, IO^, 2048, Read, nil );
   
      if Result and ( Read > 0 ) then
      begin
        Result := WriteFile( hDestFile, IO^, Read, Written, nil );
        Size   := Size - Written;
      end;
    end;
   
    if not Result then DoNotifyError( SysErrorMessage( GetLastError ) );
  end else
  begin
    DoNotifyError( SysErrorMessage( GLE ) );
  end;
 
  VirtualFree( IO, 0, MEM_RELEASE );
  CloseHandle( hSrcFile );
  CloseHandle( hDestFile );
end;

Was macht eigentlich DoNotifyError?