utils/framelayout/src/garbagec.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        No names yet.
   3 // Purpose:     Contrib. demo
   4 // Author:      Aleksandras Gluchovas (@Lithuania)
   5 // Modified by:
   6 // Created:     ??/10/98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Aleksandras Gluchovas
   9 // Licence:     wxWindows license
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 #ifndef __GARBAGEC_G__
  13 #define __GARBAGEC_G__
  14
  15 #include "wx/list.h"
  16
  17 struct GCItem
  18 {
  19         void*     mpObj;
  20         wxList    mRefs;   // references to other nodes
  21 };
  22
  23 inline void* gc_node_to_obj( wxNode* pGCNode )
  24 {
  25         return ( (GCItem*) (pGCNode->Data()) )->mpObj;
  26 }
  27
  28 // class implements extreamly slow, but probably one of the most simple GC alogrithms
  29
  30 class GarbageCollector
  31 {
  32 protected:
  33         wxList mAllNodes;
  34         wxList mRegularLst;
  35         wxList mCycledLst;
  36
  37         wxNode* FindItemNode( void* pForObj );
  38         void    ResolveReferences();
  39
  40         wxNode* FindRefernceFreeItemNode();
  41         void    RemoveReferencesToNode( wxNode* pItemNode );
  42         void    DestroyItemList( wxList& lst );
  43
  44 public:
  45
  46         GarbageCollector() {}
  47
  48         virtual ~GarbageCollector();
  49
  50         // prepare data for GC alg.
  51
  52         virtual void AddObject( void* pObj, int refCnt = 1 );
  53         virtual void AddDependency( void* pObj, void* pDepnedsOnObj );
  54
  55         // executes GC alg.
  56
  57         virtual void ArrangeCollection();
  58
  59         // acces results of the alg.
  60
  61         wxList& GetRegularObjects();
  62         wxList& GetCycledObjects();
  63
  64         // removes all date form GC
  65
  66         void Reset();
  67 };
  68
  69 #endif