1 /*
2 * Copyright (C) 2006, 2007 Apple Inc. All rights reserved.
3 * Copyright (C) 2008 Collabora Ltd.
4 *
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Library General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
9 *
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Library General Public License for more details.
14 *
15 * You should have received a copy of the GNU Library General Public License
16 * along with this library; see the file COPYING.LIB. If not, write to
17 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
18 * Boston, MA 02110-1301, USA.
19 *
20 */
21
22 #ifndef GOwnPtr_h
23 #define GOwnPtr_h
24
25 #include <algorithm>
26 #include <wtf/Assertions.h>
27 #include <wtf/Noncopyable.h>
28
29 // Forward delcarations at this point avoid the need to include GLib includes
30 // in WTF headers.
31 typedef struct _GError GError;
32 typedef struct _GList GList;
33 typedef struct _GCond GCond;
34 typedef struct _GMutex GMutex;
35 typedef struct _GPatternSpec GPatternSpec;
36 typedef struct _GDir GDir;
37 typedef struct _GHashTable GHashTable;
38 extern "C" void g_free(void*);
39
40 namespace WTF {
41
42 template <typename T> inline void freeOwnedGPtr(T* ptr);
43 template<> void freeOwnedGPtr<GError>(GError*);
44 template<> void freeOwnedGPtr<GList>(GList*);
45 template<> void freeOwnedGPtr<GCond>(GCond*);
46 template<> void freeOwnedGPtr<GMutex>(GMutex*);
47 template<> void freeOwnedGPtr<GPatternSpec>(GPatternSpec*);
48 template<> void freeOwnedGPtr<GDir>(GDir*);
49 template<> void freeOwnedGPtr<GHashTable>(GHashTable*);
50
51 template <typename T> class GOwnPtr : public Noncopyable {
52 public:
m_ptr(ptr)53 explicit GOwnPtr(T* ptr = 0) : m_ptr(ptr) { }
~GOwnPtr()54 ~GOwnPtr() { freeOwnedGPtr(m_ptr); }
55
get()56 T* get() const { return m_ptr; }
release()57 T* release()
58 {
59 T* ptr = m_ptr;
60 m_ptr = 0;
61 return ptr;
62 }
63
outPtr()64 T*& outPtr()
65 {
66 ASSERT(!m_ptr);
67 return m_ptr;
68 }
69
set(T * ptr)70 void set(T* ptr)
71 {
72 ASSERT(!ptr || m_ptr != ptr);
73 freeOwnedGPtr(m_ptr);
74 m_ptr = ptr;
75 }
76
clear()77 void clear()
78 {
79 freeOwnedGPtr(m_ptr);
80 m_ptr = 0;
81 }
82
83 T& operator*() const
84 {
85 ASSERT(m_ptr);
86 return *m_ptr;
87 }
88
89 T* operator->() const
90 {
91 ASSERT(m_ptr);
92 return m_ptr;
93 }
94
95 bool operator!() const { return !m_ptr; }
96
97 // This conversion operator allows implicit conversion to bool but not to other integer types.
98 typedef T* GOwnPtr::*UnspecifiedBoolType;
UnspecifiedBoolType()99 operator UnspecifiedBoolType() const { return m_ptr ? &GOwnPtr::m_ptr : 0; }
100
swap(GOwnPtr & o)101 void swap(GOwnPtr& o) { std::swap(m_ptr, o.m_ptr); }
102
103 private:
104 T* m_ptr;
105 };
106
swap(GOwnPtr<T> & a,GOwnPtr<T> & b)107 template <typename T> inline void swap(GOwnPtr<T>& a, GOwnPtr<T>& b)
108 {
109 a.swap(b);
110 }
111
112 template <typename T, typename U> inline bool operator==(const GOwnPtr<T>& a, U* b)
113 {
114 return a.get() == b;
115 }
116
117 template <typename T, typename U> inline bool operator==(T* a, const GOwnPtr<U>& b)
118 {
119 return a == b.get();
120 }
121
122 template <typename T, typename U> inline bool operator!=(const GOwnPtr<T>& a, U* b)
123 {
124 return a.get() != b;
125 }
126
127 template <typename T, typename U> inline bool operator!=(T* a, const GOwnPtr<U>& b)
128 {
129 return a != b.get();
130 }
131
getPtr(const GOwnPtr<T> & p)132 template <typename T> inline typename GOwnPtr<T>::PtrType getPtr(const GOwnPtr<T>& p)
133 {
134 return p.get();
135 }
136
freeOwnedGPtr(T * ptr)137 template <typename T> inline void freeOwnedGPtr(T* ptr)
138 {
139 g_free(ptr);
140 }
141
142 } // namespace WTF
143
144 using WTF::GOwnPtr;
145
146 #endif // GOwnPtr_h
147