include/library/gc.hpp

   1 #ifndef _library__gc__hpp__included__
   2 #define _library__gc__hpp__included__
   3
   4 #include <cstdlib>
   5
   6 namespace GC
   7 {
   8 class item
   9 {
  10 public:
  11         item();
  12         virtual ~item();
  13         void mark_root();
  14         void unmark_root();
  15         static void do_gc();
  16 protected:
  17         virtual void trace() = 0;
  18         void mark();
  19 private:
  20         size_t root_count;
  21         bool reachable;
  22 };
  23
  24 struct obj_tag {};
  25 template<class T> class pointer
  26 {
  27 public:
  28         pointer()
  29         {
  30                 ptr = NULL;
  31         }
  32         pointer(T* obj)
  33         {
  34                 ptr = obj;
  35         }
  36         template<typename... U> pointer(obj_tag tag, U... args)
  37         {
  38                 ptr = new T(args...);
  39         }
  40         pointer(const pointer& p)
  41         {
  42                 if(p.ptr) p.ptr->mark_root();
  43                 ptr = p.ptr;
  44         }
  45         pointer& operator=(const pointer& p)
  46         {
  47                 if(ptr == p.ptr) return *this;
  48                 if(ptr) ptr->unmark_root();
  49                 if(p.ptr) p.ptr->mark_root();
  50                 ptr = p.ptr;
  51                 return *this;
  52         }
  53         ~pointer()
  54         {
  55                 if(ptr) ptr->unmark_root();
  56         }
  57         operator bool()
  58         {
  59                 return (ptr != NULL);
  60         }
  61         T* operator->() { return ptr; }
  62         T& operator*() { return *ptr; }
  63         T* as_pointer() { return ptr; }
  64 private:
  65         T* ptr;
  66 };
  67 }
  68
  69 #endif