1 /*
2 * Copyright (C) 2006, 2010 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_OwnArrayPtr_h
22 #define WTF_OwnArrayPtr_h
23
24 #include "Assertions.h"
25 #include "Noncopyable.h"
26 #include "NullPtr.h"
27 #include "PassOwnArrayPtr.h"
28 #include <algorithm>
29
30 namespace WTF {
31
32 template<typename T> class PassOwnArrayPtr;
33 template<typename T> PassOwnArrayPtr<T> adoptArrayPtr(T*);
34
35 template <typename T> class OwnArrayPtr {
36 public:
37 typedef T* PtrType;
38
OwnArrayPtr()39 OwnArrayPtr() : m_ptr(0) { }
40
41 // See comment in PassOwnArrayPtr.h for why this takes a const reference.
42 template<typename U> OwnArrayPtr(const PassOwnArrayPtr<U>& o);
43
44 // This copy constructor is used implicitly by gcc when it generates
45 // transients for assigning a PassOwnArrayPtr<T> object to a stack-allocated
46 // OwnArrayPtr<T> object. It should never be called explicitly and gcc
47 // should optimize away the constructor when generating code.
48 OwnArrayPtr(const OwnArrayPtr<T>&);
49
~OwnArrayPtr()50 ~OwnArrayPtr() { deleteOwnedArrayPtr(m_ptr); }
51
get()52 PtrType get() const { return m_ptr; }
53
54 void clear();
55 PassOwnArrayPtr<T> release();
56 PtrType leakPtr() WARN_UNUSED_RETURN;
57
58 T& operator*() const { ASSERT(m_ptr); return *m_ptr; }
59 PtrType operator->() const { ASSERT(m_ptr); return m_ptr; }
60
61 T& operator[](std::ptrdiff_t i) const { ASSERT(m_ptr); ASSERT(i >= 0); return m_ptr[i]; }
62
63 bool operator!() const { return !m_ptr; }
64
65 // This conversion operator allows implicit conversion to bool but not to other integer types.
66 #if COMPILER(WINSCW)
67 operator bool() const { return m_ptr; }
68 #else
69 typedef T* OwnArrayPtr::*UnspecifiedBoolType;
UnspecifiedBoolType()70 operator UnspecifiedBoolType() const { return m_ptr ? &OwnArrayPtr::m_ptr : 0; }
71 #endif
72
73 OwnArrayPtr& operator=(const PassOwnArrayPtr<T>&);
74 OwnArrayPtr& operator=(std::nullptr_t) { clear(); return *this; }
75 template<typename U> OwnArrayPtr& operator=(const PassOwnArrayPtr<U>&);
76
swap(OwnArrayPtr & o)77 void swap(OwnArrayPtr& o) { std::swap(m_ptr, o.m_ptr); }
78
79 #ifdef LOOSE_OWN_ARRAY_PTR
OwnArrayPtr(PtrType ptr)80 explicit OwnArrayPtr(PtrType ptr) : m_ptr(ptr) { }
81 void set(PtrType);
82 #endif
83
84 private:
85 PtrType m_ptr;
86 };
87
OwnArrayPtr(const PassOwnArrayPtr<U> & o)88 template<typename T> template<typename U> inline OwnArrayPtr<T>::OwnArrayPtr(const PassOwnArrayPtr<U>& o)
89 : m_ptr(o.leakPtr())
90 {
91 }
92
clear()93 template<typename T> inline void OwnArrayPtr<T>::clear()
94 {
95 PtrType ptr = m_ptr;
96 m_ptr = 0;
97 deleteOwnedArrayPtr(ptr);
98 }
99
release()100 template<typename T> inline PassOwnArrayPtr<T> OwnArrayPtr<T>::release()
101 {
102 PtrType ptr = m_ptr;
103 m_ptr = 0;
104 return adoptArrayPtr(ptr);
105 }
106
leakPtr()107 template<typename T> inline typename OwnArrayPtr<T>::PtrType OwnArrayPtr<T>::leakPtr()
108 {
109 PtrType ptr = m_ptr;
110 m_ptr = 0;
111 return ptr;
112 }
113
114 #ifdef LOOSE_OWN_ARRAY_PTR
set(PtrType ptr)115 template<typename T> inline void OwnArrayPtr<T>::set(PtrType ptr)
116 {
117 ASSERT(!ptr || m_ptr != ptr);
118 PtrType oldPtr = m_ptr;
119 m_ptr = ptr;
120 deleteOwnedArrayPtr(oldPtr);
121 }
122 #endif
123
124 template<typename T> inline OwnArrayPtr<T>& OwnArrayPtr<T>::operator=(const PassOwnArrayPtr<T>& o)
125 {
126 PtrType ptr = m_ptr;
127 m_ptr = o.leakPtr();
128 ASSERT(!ptr || m_ptr != ptr);
129 deleteOwnedArrayPtr(ptr);
130 return *this;
131 }
132
133 template<typename T> template<typename U> inline OwnArrayPtr<T>& OwnArrayPtr<T>::operator=(const PassOwnArrayPtr<U>& o)
134 {
135 PtrType ptr = m_ptr;
136 m_ptr = o.leakPtr();
137 ASSERT(!ptr || m_ptr != ptr);
138 deleteOwnedArrayPtr(ptr);
139 return *this;
140 }
141
swap(OwnArrayPtr<T> & a,OwnArrayPtr<T> & b)142 template <typename T> inline void swap(OwnArrayPtr<T>& a, OwnArrayPtr<T>& b)
143 {
144 a.swap(b);
145 }
146
147 template<typename T, typename U> inline bool operator==(const OwnArrayPtr<T>& a, U* b)
148 {
149 return a.get() == b;
150 }
151
152 template<typename T, typename U> inline bool operator==(T* a, const OwnArrayPtr<U>& b)
153 {
154 return a == b.get();
155 }
156
157 template<typename T, typename U> inline bool operator!=(const OwnArrayPtr<T>& a, U* b)
158 {
159 return a.get() != b;
160 }
161
162 template<typename T, typename U> inline bool operator!=(T* a, const OwnArrayPtr<U>& b)
163 {
164 return a != b.get();
165 }
166
getPtr(const OwnArrayPtr<T> & p)167 template <typename T> inline T* getPtr(const OwnArrayPtr<T>& p)
168 {
169 return p.get();
170 }
171
172 } // namespace WTF
173
174 using WTF::OwnArrayPtr;
175
176 #endif // WTF_OwnArrayPtr_h
177