1 // Copyright (C) 2001-2005 Open Source Telecom Corporation.
2 // Copyright (C) 2006-2014 David Sugar, Tycho Softworks.
3 // Copyright (C) 2015 Cherokees of Idaho.
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41 
42 /**
43  * @file commoncpp/pointer.h
44  * @short Template for creating reference count managed smart pointers.
45  **/
46 
47 #ifndef COMMONCPP_POINTER_H_
48 #define COMMONCPP_POINTER_H_
49 
50 #ifndef COMMONCPP_CONFIG_H_
51 #include <commoncpp/config.h>
52 #endif
53 
54 namespace ost {
55 
56 /**
57  * Used to create and manage referece counted pointers.
58  *
59  * @author David Sugar <dyfet@gnutelephony.org>
60  * @short reference counted pointer template.
61  */
62 template <class T>
63 class Pointer
64 {
65 protected:
66     unsigned *ptrCount;
67     T *ptrObject;
68 
ptrDetach(void)69     inline void ptrDetach(void) {
70         if(ptrCount && --(*ptrCount)==0) {
71             delete ptrObject;
72             delete ptrCount;
73         }
74         ptrObject = NULL;
75         ptrCount = NULL;
76     }
77 
78 public:
ptrObject(ptr)79     inline explicit Pointer(T* ptr = NULL) : ptrObject(ptr) {
80         ptrCount = new unsigned;
81         *ptrCount = 1;
82     }
83 
Pointer(const Pointer<T> & ref)84     inline Pointer(const Pointer<T> &ref) {
85         ptrObject = ref.ptrObject;
86         ptrCount = ref.ptrCount;
87         ++(*ptrCount);
88     }
89 
~Pointer()90     inline virtual ~Pointer() {
91         ptrDetach();
92     }
93 
94     inline Pointer& operator=(const Pointer<T> &ref) {
95         if(this != &ref) {
96             ptrDetach();
97             ptrObject = ref.ptrObject;
98             ptrCount = ref.ptrCount;
99             ++(*ptrCount);
100         }
101         return *this;
102     }
103 
104     inline T& operator*() const {
105         return *ptrObject;
106     }
107 
getObject()108     inline T* getObject() const {
109         return ptrObject;
110     }
111 
112     inline T* operator->() const {
113         return ptrObject;
114     }
115 
116     inline operator bool() const {
117         return (*ptrCount != 1);
118     }
119 
120     inline bool operator!() const {
121         return (*ptrCount == 1);
122     }
123 
124     inline int operator++() const {
125         return ++(*ptrCount);
126     }
127 
128     inline int operator--() const {
129         if(*ptrCount == 1) {
130             delete this;
131             return 0;
132         }
133         return --(*ptrCount);
134     }
135 };
136 
137 } // namespace ost
138 
139 #endif
140