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
13namespace antlr {
14#endif
15
16template<class T>
17class ANTLR_API RefCount {
18private:
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
32public:
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__
81