OSX/libsecurity_codesigning/antlr2/antlr/RefCount.hpp

   1 #ifndef INC_RefCount_hpp__
   2 #define INC_RefCount_hpp__
   3 /* ANTLR Translator Generator
   4  * Project led by Terence Parr at http://www.jGuru.com
   5  * Software rights: http://www.antlr.org/license.html
   6  *
   7  * $Id: //depot/code/org.antlr/release/antlr-2.7.7/lib/cpp/antlr/RefCount.hpp#2 $
   8  */
   9
  10 #include <antlr/config.hpp>
  11
  12 #ifdef ANTLR_CXX_SUPPORTS_NAMESPACE
  13 namespace antlr {
  14 #endif
  15
  16 template<class T>
  17 class ANTLR_API RefCount {
  18 private:
  19         struct Ref {
  20                 T* const ptr;
  21                 unsigned int count;
  22
  23                 Ref(T* p) : ptr(p), count(1) {}
  24                 ~Ref() {delete ptr;}
  25                 Ref* increment() {++count;return this;}
  26                 bool decrement() {return (--count==0);}
  27         private:
  28                 Ref(const Ref&);
  29                 Ref& operator=(const Ref&);
  30         }* ref;
  31
  32 public:
  33         explicit RefCount(T* p = 0)
  34         : ref(p ? new Ref(p) : 0)
  35         {
  36         }
  37         RefCount(const RefCount<T>& other)
  38         : ref(other.ref ? other.ref->increment() : 0)
  39         {
  40         }
  41         ~RefCount()
  42         {
  43                 if (ref && ref->decrement())
  44                         delete ref;
  45         }
  46         RefCount<T>& operator=(const RefCount<T>& other)
  47         {
  48                 Ref* tmp = other.ref ? other.ref->increment() : 0;
  49                 if (ref && ref->decrement())
  50                         delete ref;
  51                 ref = tmp;
  52                 return *this;
  53         }
  54
  55         operator T* () const
  56         {
  57                 return ref ? ref->ptr : 0;
  58         }
  59
  60         T* operator->() const
  61         {
  62                 return ref ? ref->ptr : 0;
  63         }
  64
  65         T* get() const
  66         {
  67                 return ref ? ref->ptr : 0;
  68         }
  69
  70         template<class newType> operator RefCount<newType>()
  71         {
  72                 return RefCount<newType>(ref);
  73         }
  74 };
  75
  76 #ifdef ANTLR_CXX_SUPPORTS_NAMESPACE
  77 }
  78 #endif
  79
  80 #endif //INC_RefCount_hpp__