cpp_code_fragment/checked_ptr.h at master · gmmybu/cpp_code_fragment · GitHub

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
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
#pragma once
#include "trace.h"
#include <typeinfo>
#include <string.h>

namespace checked_ptr_deleter {

template<class T>
struct Default_Deleter
{
    void operator()(T* ptr) { delete ptr; }
};

template<class T>
struct Release_Deleter
{
    void operator()(T* ptr)
    {
        if (ptr != nullptr) {
            ptr->release();
        }
    }
};

template<class T>
struct DoNothing_Deleter
{
    void operator()(T* ptr) {}
};

}

template<class T, class Deleter>
class checked_ptr
{
protected:
    checked_ptr(T* ptr, const char* name) :
        _ptr(ptr), _name(name)
    {
        if (_name == nullptr) {
            _name = "noname";
        }

        if (strncmp(_name, "class ", 6) == 0) {
            _name += 6;
        }

        if (strncmp(_name, "struct ", 7) == 0) {
            _name += 7;
        }
    }

    ~checked_ptr()
    {
        destroy();
    }
public:
    void reset(T* ptr)
    {
        if (_ptr != ptr) {
            destroy();
            _ptr = ptr;
        }
    }

    void destroy()
    {
        Deleter deleter;
        deleter(_ptr);
        _ptr = nullptr;
    }

    T* release()
    {
        T* ptr = _ptr;
        _ptr = nullptr;
        return ptr;
    }

    T* get() const
    {
        return _ptr;
    }

    bool empty() const
    {
        return _ptr == nullptr;
    }
public:
    T* operator->() const
    {
        if (_ptr == nullptr) {
            logger_error_va("%s is nullptr when call member function", _name);
            abort();
        }

        return _ptr;
    }

    operator T*() const
    {
        return _ptr;
    }
protected:
    T* _ptr;
    const char* _name;
private:
    checked_ptr(const checked_ptr&);
    checked_ptr& operator=(const checked_ptr&);
};

template<class T, class D>
bool operator==(const checked_ptr<T, D>& left, std::nullptr_t)
{
    return left.empty();
}

template<class T, class D>
bool operator==(std::nullptr_t, const checked_ptr<T, D>& right)
{
    return right.empty();
}

template<class T, class D>
bool operator!=(const checked_ptr<T, D>& left, std::nullptr_t)
{
    return !left.empty();
}

template<class T, class D>
bool operator!=(std::nullptr_t, const checked_ptr<T, D>& right)
{
    return !right.empty();
}

template<class T>
class checked_release_ptr : public checked_ptr<T, checked_ptr_deleter::Release_Deleter<T>>
{
public:
    checked_release_ptr(T* ptr, const char* name = typeid(T).name()) :
        checked_ptr(ptr, name) {}
};

template<class T>
class checked_delete_ptr : public checked_ptr<T, checked_ptr_deleter::Default_Deleter<T>>
{
public:
    checked_delete_ptr(T* ptr, const char* name = typeid(T).name()) :
        checked_ptr(ptr, name) {}
};

template<class T>
class checked_useonly_ptr : public checked_ptr<T, checked_ptr_deleter::DoNothing_Deleter<T>>
{
public:
    checked_useonly_ptr(T* ptr, const char* name = typeid(T).name()) :
        checked_ptr(ptr, name) {}
};