src/sptr.h


1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144

#ifndef SPTR_H
#define SPTR_H

#include <stdint.h>
#include <stdio.h>

template<typename T> class SPtr;
template< typename Tb, typename Ta > SPtr<Tb> SPtrCast( SPtr<Ta> src );

template<typename T>
class SPtr
{
	template<typename Tb, typename Ta>
	friend SPtr<Tb> SPtrCast( SPtr<Ta> pt );
public:
	SPtr() :
		pRefCnt( NULL ),
		pData( NULL )
	{
	}

	~SPtr()
	{
		decCount();
	}

	SPtr( const SPtr<T> &src ) :
		pRefCnt( src.pRefCnt ),
		pData( src.pData )
	{
		if( pRefCnt )
			(*pRefCnt) += 1;
	}

	SPtr( T *pSrc ) :
		pRefCnt( NULL ),
		pData( pSrc )
	{
		if( pData )
		{
			pRefCnt = new int32_t;
			(*pRefCnt) = 1;
		}
	}

	int32_t count() const
	{
		return *pRefCnt;
	}

	const T *operator->() const
	{
		return pData;
	}

	const T &operator*() const
	{
		return *pData;
	}
	
	T *operator->()
	{
		return pData;
	}

	T &operator*()
	{
		return *pData;
	}

	SPtr<T> operator=( const SPtr<T> &src )
	{
		decCount();
		pRefCnt = src.pRefCnt;
		pData = src.pData;
		if( pRefCnt )
			(*pRefCnt) += 1;

		return *this;
	}

	const SPtr<T> operator=( const SPtr<T> &src ) const
	{
		decCount();
		pRefCnt = src.pRefCnt;
		pData = src.pData;
		if( pRefCnt )
			(*pRefCnt) += 1;

		return *this;
	}

	bool operator==( const SPtr<T> &src ) const
	{
		return pData == src.pData;
	}

	bool operator==( const T *src ) const
	{
		return pData == src;
	}

	operator bool() const
	{
		return pRefCnt != NULL;
	}

	bool isSet() const
	{
		return pRefCnt != NULL;
	}

private:
	void decCount() const
	{
		if( pRefCnt )
		{
			(*pRefCnt) -= 1;
			//printf("Decrementing ref-count to %d\n", *pRefCnt );
			if( (*pRefCnt) == 0 )
			{
				delete pRefCnt;
				delete pData;
				pRefCnt = NULL;
				pData = NULL;
			}
		}
	}

	mutable int32_t *pRefCnt;
	mutable T *pData;
};

template< typename Tb, typename Ta > SPtr<Tb> SPtrCast( SPtr<Ta> src )
{
	SPtr<Tb> ret;
	ret.pRefCnt = src.pRefCnt;
	ret.pData = dynamic_cast<Tb *>(src.pData);
	if( ret.pRefCnt )
		(*(ret.pRefCnt)) += 1;
	return ret;
}

#endif