diff options
Diffstat (limited to 'src/FbTk/RefCount.hh')
-rw-r--r-- | src/FbTk/RefCount.hh | 129 |
1 files changed, 129 insertions, 0 deletions
diff --git a/src/FbTk/RefCount.hh b/src/FbTk/RefCount.hh new file mode 100644 index 0000000..737ee1b --- /dev/null +++ b/src/FbTk/RefCount.hh | |||
@@ -0,0 +1,129 @@ | |||
1 | // RefCount.hh for FbTk - Fluxbox Toolkit | ||
2 | // Copyright (c) 2002 Henrik Kinnunen (fluxgen at users.sourceforge.net) | ||
3 | // | ||
4 | // Permission is hereby granted, free of charge, to any person obtaining a | ||
5 | // copy of this software and associated documentation files (the "Software"), | ||
6 | // to deal in the Software without restriction, including without limitation | ||
7 | // the rights to use, copy, modify, merge, publish, distribute, sublicense, | ||
8 | // and/or sell copies of the Software, and to permit persons to whom the | ||
9 | // Software is furnished to do so, subject to the following conditions: | ||
10 | // | ||
11 | // The above copyright notice and this permission notice shall be included in | ||
12 | // all copies or substantial portions of the Software. | ||
13 | // | ||
14 | // THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR | ||
15 | // IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, | ||
16 | // FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL | ||
17 | // THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER | ||
18 | // LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING | ||
19 | // FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER | ||
20 | // DEALINGS IN THE SOFTWARE. | ||
21 | |||
22 | #ifndef FBTK_REFCOUNT_HH | ||
23 | #define FBTK_REFCOUNT_HH | ||
24 | |||
25 | namespace FbTk { | ||
26 | |||
27 | /// holds a pointer with reference counting, similar to std:auto_ptr | ||
28 | template <typename Pointer> | ||
29 | class RefCount { | ||
30 | public: | ||
31 | RefCount(); | ||
32 | explicit RefCount(Pointer *p); | ||
33 | explicit RefCount(RefCount<Pointer> ©); | ||
34 | RefCount(const RefCount<Pointer> ©); | ||
35 | ~RefCount(); | ||
36 | RefCount<Pointer> &operator = (const RefCount<Pointer> ©); | ||
37 | RefCount<Pointer> &operator = (Pointer *p); | ||
38 | Pointer *operator * () const { return get(); } | ||
39 | Pointer *operator -> () const { return get(); } | ||
40 | Pointer *get() const { return m_data; } | ||
41 | /// @return number of referenses | ||
42 | unsigned int usedBy() const { return (m_refcount != 0 ? *m_refcount : 0); } | ||
43 | private: | ||
44 | /// increase referense count | ||
45 | void incRefCount(); | ||
46 | /// decrease referense count | ||
47 | void decRefCount(); | ||
48 | Pointer *m_data; ///< data holder | ||
49 | mutable unsigned int *m_refcount; ///< holds reference counting | ||
50 | }; | ||
51 | |||
52 | // implementation | ||
53 | |||
54 | template <typename Pointer> | ||
55 | RefCount<Pointer>::RefCount():m_data(0), m_refcount(new unsigned int(0)) { | ||
56 | |||
57 | } | ||
58 | |||
59 | template <typename Pointer> | ||
60 | RefCount<Pointer>::RefCount(RefCount<Pointer> ©): | ||
61 | m_data(copy.m_data), | ||
62 | m_refcount(copy.m_refcount) { | ||
63 | incRefCount(); | ||
64 | } | ||
65 | |||
66 | template <typename Pointer> | ||
67 | RefCount<Pointer>::RefCount(Pointer *p):m_data(p), m_refcount(new unsigned int(0)) { | ||
68 | incRefCount(); | ||
69 | } | ||
70 | |||
71 | template <typename Pointer> | ||
72 | RefCount<Pointer>::RefCount(const RefCount<Pointer> ©): | ||
73 | m_data(copy.m_data), | ||
74 | m_refcount(copy.m_refcount) { | ||
75 | incRefCount(); | ||
76 | } | ||
77 | |||
78 | template <typename Pointer> | ||
79 | RefCount<Pointer>::~RefCount() { | ||
80 | decRefCount(); | ||
81 | } | ||
82 | |||
83 | template <typename Pointer> | ||
84 | RefCount<Pointer> &RefCount<Pointer>::operator = (const RefCount<Pointer> ©) { | ||
85 | decRefCount(); // dec current ref count | ||
86 | m_refcount = copy.m_refcount; // set new ref count | ||
87 | m_data = copy.m_data; // set new data pointer | ||
88 | incRefCount(); // inc new ref count | ||
89 | return *this; | ||
90 | } | ||
91 | |||
92 | template <typename Pointer> | ||
93 | RefCount<Pointer> &RefCount<Pointer>::operator = (Pointer *p) { | ||
94 | decRefCount(); | ||
95 | m_data = p; // set data pointer | ||
96 | m_refcount = new unsigned int(0); // create new counter | ||
97 | incRefCount(); | ||
98 | return *this; | ||
99 | } | ||
100 | |||
101 | template <typename Pointer> | ||
102 | void RefCount<Pointer>::decRefCount() { | ||
103 | if (m_refcount == 0) | ||
104 | return; | ||
105 | if (*m_refcount == 0) { // already zero, then delete refcount | ||
106 | delete m_refcount; | ||
107 | m_refcount = 0; | ||
108 | return; | ||
109 | } | ||
110 | (*m_refcount)--; | ||
111 | if (*m_refcount == 0) { // destroy m_data and m_refcount if nobody else is using this | ||
112 | if (m_data != 0) | ||
113 | delete m_data; | ||
114 | m_data = 0; | ||
115 | delete m_refcount; | ||
116 | m_refcount = 0; | ||
117 | } | ||
118 | } | ||
119 | |||
120 | template <typename Pointer> | ||
121 | void RefCount<Pointer>::incRefCount() { | ||
122 | if (m_refcount == 0) | ||
123 | return; | ||
124 | (*m_refcount)++; | ||
125 | } | ||
126 | |||
127 | }; // end namespace FbTk | ||
128 | |||
129 | #endif // FBTK_REFCOUNT_HH | ||