1/*
2 * Copyright (C) 2006, 2007, 2008, 2009 Apple Inc. All rights reserved.
3 *
4 * This library is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU Library General Public
6 * License as published by the Free Software Foundation; either
7 * version 2 of the License, or (at your option) any later version.
8 *
9 * This library is distributed in the hope that it will be useful,
10 * but WITHOUT ANY WARRANTY; without even the implied warranty of
11 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
12 * Library General Public License for more details.
13 *
14 * You should have received a copy of the GNU Library General Public License
15 * along with this library; see the file COPYING.LIB. If not, write to
16 * the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
17 * Boston, MA 02110-1301, USA.
18 *
19 */
20
21#ifndef WTF_OwnPtr_h
22#define WTF_OwnPtr_h
23
24#include "Assertions.h"
25#include "Noncopyable.h"
26#include "OwnPtrCommon.h"
27#include "TypeTraits.h"
28#include <algorithm>
29#include <memory>
30
31namespace WTF {
32
33 // Unlike most of our smart pointers, OwnPtr can take either the pointer type or the pointed-to type.
34
35 template <typename T> class PassOwnPtr;
36
37 template <typename T> class OwnPtr : public Noncopyable {
38 public:
39 typedef typename RemovePointer<T>::Type ValueType;
40 typedef ValueType* PtrType;
41
42 explicit OwnPtr(PtrType ptr = 0) : m_ptr(ptr) { }
43 OwnPtr(std::auto_ptr<ValueType> autoPtr) : m_ptr(autoPtr.release()) { }
44 // See comment in PassOwnPtr.h for why this takes a const reference.
45 template <typename U> OwnPtr(const PassOwnPtr<U>& o);
46
47 // This copy constructor is used implicitly by gcc when it generates
48 // transients for assigning a PassOwnPtr<T> object to a stack-allocated
49 // OwnPtr<T> object. It should never be called explicitly and gcc
50 // should optimize away the constructor when generating code.
51 OwnPtr(const OwnPtr<ValueType>& o);
52
53 ~OwnPtr() { deleteOwnedPtr(m_ptr); }
54
55 PtrType get() const { return m_ptr; }
56 PtrType release() { PtrType ptr = m_ptr; m_ptr = 0; return ptr; }
57
58 // FIXME: This should be renamed to adopt.
59 void set(PtrType ptr) { ASSERT(!ptr || m_ptr != ptr); deleteOwnedPtr(m_ptr); m_ptr = ptr; }
60
61 void adopt(std::auto_ptr<ValueType> autoPtr) { ASSERT(!autoPtr.get() || m_ptr != autoPtr.get()); deleteOwnedPtr(m_ptr); m_ptr = autoPtr.release(); }
62
63 void clear() { deleteOwnedPtr(m_ptr); m_ptr = 0; }
64
65 ValueType& operator*() const { ASSERT(m_ptr); return *m_ptr; }
66 PtrType operator->() const { ASSERT(m_ptr); return m_ptr; }
67
68 bool operator!() const { return !m_ptr; }
69
70 // This conversion operator allows implicit conversion to bool but not to other integer types.
71 typedef PtrType OwnPtr::*UnspecifiedBoolType;
72 operator UnspecifiedBoolType() const { return m_ptr ? &OwnPtr::m_ptr : 0; }
73
74 OwnPtr& operator=(const PassOwnPtr<T>&);
75 template <typename U> OwnPtr& operator=(const PassOwnPtr<U>&);
76
77 void swap(OwnPtr& o) { std::swap(m_ptr, o.m_ptr); }
78
79 private:
80 PtrType m_ptr;
81 };
82
83 template <typename T> template <typename U> inline OwnPtr<T>::OwnPtr(const PassOwnPtr<U>& o)
84 : m_ptr(o.release())
85 {
86 }
87
88 template <typename T> inline OwnPtr<T>& OwnPtr<T>::operator=(const PassOwnPtr<T>& o)
89 {
90 T* ptr = m_ptr;
91 m_ptr = o.release();
92 ASSERT(!ptr || m_ptr != ptr);
93 if (ptr)
94 deleteOwnedPtr(ptr);
95 return *this;
96 }
97
98 template <typename T> template <typename U> inline OwnPtr<T>& OwnPtr<T>::operator=(const PassOwnPtr<U>& o)
99 {
100 T* ptr = m_ptr;
101 m_ptr = o.release();
102 ASSERT(!ptr || m_ptr != ptr);
103 if (ptr)
104 deleteOwnedPtr(ptr);
105 return *this;
106 }
107
108 template <typename T> inline void swap(OwnPtr<T>& a, OwnPtr<T>& b)
109 {
110 a.swap(b);
111 }
112
113 template <typename T, typename U> inline bool operator==(const OwnPtr<T>& a, U* b)
114 {
115 return a.get() == b;
116 }
117
118 template <typename T, typename U> inline bool operator==(T* a, const OwnPtr<U>& b)
119 {
120 return a == b.get();
121 }
122
123 template <typename T, typename U> inline bool operator!=(const OwnPtr<T>& a, U* b)
124 {
125 return a.get() != b;
126 }
127
128 template <typename T, typename U> inline bool operator!=(T* a, const OwnPtr<U>& b)
129 {
130 return a != b.get();
131 }
132
133 template <typename T> inline typename OwnPtr<T>::PtrType getPtr(const OwnPtr<T>& p)
134 {
135 return p.get();
136 }
137
138} // namespace WTF
139
140using WTF::OwnPtr;
141
142#endif // WTF_OwnPtr_h
143

source code of qtscript/src/3rdparty/javascriptcore/JavaScriptCore/wtf/OwnPtr.h