Stack programmieren / postfix

[taaktaak]

Bonjour Robespierre, comment ca va?

Wie wäre es mit folgendem Beispiel für einen universellen LiFo-Puffer...

Delphi-Quellcode:

type _Mem_Space       = Array[0..maxInt-1]of Byte;   
     _L_List          = ^_L_List_Node;                  
     _L_List_Node     = record                 
                         Size  : Integer;
                         Info  : ^_Mem_Space;
                         Next  : _L_List end;
     TLiFo            = _L_List;     

// ----------------------------------------------------- LiFo - LastIn/FirstOut

procedure InitLiFo(var L:TLiFo);
begin
  L:=nil;
end;

procedure FreeLiFo(var L:TLiFo);
var p : TLiFo;
begin
  while L<>nil do begin
    p:=L;
    with p^ do begin
      FreeMem(Info,Size);
      L:=Next;
      end;
    end;
end;

function IsEmpty(L:TLiFo):Boolean;
begin
  Result:=L=nil
end;

function LiFoCount(L:TLiFo):Integer;
var p : TLiFo;
begin
  Result:=0;
  while L<>nil do begin
    p:=L;
    L:=p^.Next;
    inc(Result);
    end;
end;

procedure Push(var L:TLiFo;var Value;Len:Integer);
var p : TLiFo;
begin
  new(p);
  with p^ do begin
    Size:=Len;
    Next:=L;
    GetMem(Info,Size);
    Move(Value,Info^,Size);
    end;
  L:=p;
end;

procedure Pop(var L:TLiFo;var Value;Len:Integer);
var p : TLiFo;
begin
  p:=L;
  with p^ do begin
    if Size<>Len then begin ShowMessage('Variablenlänge inkompatibel');
                            exit;
                            end;
    Move(Info^,Value,Size);
    FreeMem(Info,Size);
    L:=Next;
    end;
end;