contrib/include/wx/fl/garbagec.h

   1 /////////////////////////////////////////////////////////////////////////////
   2 // Name:        garbagec.h
   3 // Purpose:     GarbageCollector class.
   4 // Author:      Aleksandras Gluchovas (@Lithuania)
   5 // Modified by:
   6 // Created:     ??/10/98
   7 // RCS-ID:      $Id$
   8 // Copyright:   (c) Aleksandras Gluchovas
   9 // Licence:     wxWindows licence
  10 /////////////////////////////////////////////////////////////////////////////
  11
  12 #ifndef __GARBAGEC_G__
  13 #define __GARBAGEC_G__
  14
  15 #include "wx/list.h"
  16 #include "wx/fl/fldefs.h"
  17
  18 struct GCItem
  19 {
  20     void*      mpObj;
  21     wxList    mRefs;   // references to other nodes
  22 };
  23
  24 inline void* gc_node_to_obj( wxObjectList::compatibility_iterator pGCNode )
  25 {
  26     return ( (GCItem*) (pGCNode->GetData()) )->mpObj;
  27 }
  28
  29 /*
  30 This class implements an extremely slow but simple garbage collection algorithm.
  31 */
  32
  33 class WXDLLIMPEXP_FL GarbageCollector
  34 {
  35 protected:
  36     wxList mAllNodes;
  37     wxList mRegularLst;
  38     wxList mCycledLst;
  39
  40         // Internal method for finding a node.
  41     wxNode* FindItemNode( void* pForObj );
  42
  43         // Internal method for resolving references.
  44     void    ResolveReferences();
  45
  46         // Internal method for findind and freeing a node.
  47     wxNode* FindReferenceFreeItemNode();
  48
  49         // Remove references to this node.
  50     void    RemoveReferencesToNode( wxNode* pItemNode );
  51
  52         // Destroys a list of items.
  53     void    DestroyItemList( wxList& lst );
  54
  55 public:
  56
  57         // Default constructor.
  58     GarbageCollector() {}
  59
  60         // Destructor.
  61     virtual ~GarbageCollector();
  62
  63         // Prepare data for garbage collection.
  64
  65     virtual void AddObject( void* pObj, int refCnt = 1 );
  66
  67         // Prepare data for garbage collection.
  68
  69     virtual void AddDependency( void* pObj, void* pDependsOnObj );
  70
  71         // Executes garbage collection algorithm.
  72
  73     virtual void ArrangeCollection();
  74
  75         // Accesses the results of the algorithm.
  76
  77     wxList& GetRegularObjects();
  78
  79         // Get cycled objects.
  80
  81     wxList& GetCycledObjects();
  82
  83         // Removes all data from the garbage collector.
  84
  85     void Reset();
  86 };
  87
  88 #endif /* __GARBAGEC_G__ */
  89