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39
40#ifndef QSCOPEDPOINTER_H
41#define QSCOPEDPOINTER_H
42
43#include <QtCore/qglobal.h>
44
45#include <stdlib.h>
46
47QT_BEGIN_NAMESPACE
48
49template <typename T>
50struct QScopedPointerDeleter
51{
52 static inline void cleanup(T *pointer)
53 {
54 // Enforce a complete type.
55 // If you get a compile error here, read the section on forward declared
56 // classes in the QScopedPointer documentation.
57 typedef char IsIncompleteType[ sizeof(T) ? 1 : -1 ];
58 (void) sizeof(IsIncompleteType);
59
60 delete pointer;
61 }
62};
63
64template <typename T>
65struct QScopedPointerArrayDeleter
66{
67 static inline void cleanup(T *pointer)
68 {
69 // Enforce a complete type.
70 // If you get a compile error here, read the section on forward declared
71 // classes in the QScopedPointer documentation.
72 typedef char IsIncompleteType[ sizeof(T) ? 1 : -1 ];
73 (void) sizeof(IsIncompleteType);
74
75 delete[] pointer;
76 }
77};
78
79struct QScopedPointerPodDeleter
80{
81 static inline void cleanup(void *pointer) { if (pointer) free(pointer); }
82};
83
84#ifndef QT_NO_QOBJECT
85template <typename T>
86struct QScopedPointerObjectDeleteLater
87{
88 static inline void cleanup(T *pointer) { if (pointer) pointer->deleteLater(); }
89};
90
91class QObject;
92typedef QScopedPointerObjectDeleteLater<QObject> QScopedPointerDeleteLater;
93#endif
94
95template <typename T, typename Cleanup = QScopedPointerDeleter<T> >
96class QScopedPointer
97{
98public:
99 explicit QScopedPointer(T *p = nullptr) noexcept : d(p)
100 {
101 }
102
103 inline ~QScopedPointer()
104 {
105 T *oldD = this->d;
106 Cleanup::cleanup(oldD);
107 }
108
109 inline T &operator*() const
110 {
111 Q_ASSERT(d);
112 return *d;
113 }
114
115 T *operator->() const noexcept
116 {
117 return d;
118 }
119
120 bool operator!() const noexcept
121 {
122 return !d;
123 }
124
125 explicit operator bool() const
126 {
127 return !isNull();
128 }
129
130 T *data() const noexcept
131 {
132 return d;
133 }
134
135 T *get() const noexcept
136 {
137 return d;
138 }
139
140 bool isNull() const noexcept
141 {
142 return !d;
143 }
144
145 void reset(T *other = nullptr) noexcept(noexcept(Cleanup::cleanup(std::declval<T *>())))
146 {
147 if (d == other)
148 return;
149 T *oldD = d;
150 d = other;
151 Cleanup::cleanup(oldD);
152 }
153
154 T *take() noexcept
155 {
156 T *oldD = d;
157 d = nullptr;
158 return oldD;
159 }
160
161 void swap(QScopedPointer<T, Cleanup> &other) noexcept
162 {
163 qSwap(d, other.d);
164 }
165
166 typedef T *pointer;
167
168protected:
169 T *d;
170
171private:
172 Q_DISABLE_COPY(QScopedPointer)
173};
174
175template <class T, class Cleanup>
176inline bool operator==(const QScopedPointer<T, Cleanup> &lhs, const QScopedPointer<T, Cleanup> &rhs) noexcept
177{
178 return lhs.data() == rhs.data();
179}
180
181template <class T, class Cleanup>
182inline bool operator!=(const QScopedPointer<T, Cleanup> &lhs, const QScopedPointer<T, Cleanup> &rhs) noexcept
183{
184 return lhs.data() != rhs.data();
185}
186
187template <class T, class Cleanup>
188inline bool operator==(const QScopedPointer<T, Cleanup> &lhs, std::nullptr_t) noexcept
189{
190 return lhs.isNull();
191}
192
193template <class T, class Cleanup>
194inline bool operator==(std::nullptr_t, const QScopedPointer<T, Cleanup> &rhs) noexcept
195{
196 return rhs.isNull();
197}
198
199template <class T, class Cleanup>
200inline bool operator!=(const QScopedPointer<T, Cleanup> &lhs, std::nullptr_t) noexcept
201{
202 return !lhs.isNull();
203}
204
205template <class T, class Cleanup>
206inline bool operator!=(std::nullptr_t, const QScopedPointer<T, Cleanup> &rhs) noexcept
207{
208 return !rhs.isNull();
209}
210
211template <class T, class Cleanup>
212inline void swap(QScopedPointer<T, Cleanup> &p1, QScopedPointer<T, Cleanup> &p2) noexcept
213{ p1.swap(p2); }
214
215template <typename T, typename Cleanup = QScopedPointerArrayDeleter<T> >
216class QScopedArrayPointer : public QScopedPointer<T, Cleanup>
217{
218 template <typename Ptr>
219 using if_same_type = typename std::enable_if<std::is_same<typename std::remove_cv<T>::type, Ptr>::value, bool>::type;
220public:
221 inline QScopedArrayPointer() : QScopedPointer<T, Cleanup>(nullptr) {}
222
223 template <typename D, if_same_type<D> = true>
224 explicit QScopedArrayPointer(D *p)
225 : QScopedPointer<T, Cleanup>(p)
226 {
227 }
228
229 inline T &operator[](int i)
230 {
231 return this->d[i];
232 }
233
234 inline const T &operator[](int i) const
235 {
236 return this->d[i];
237 }
238
239 void swap(QScopedArrayPointer &other) noexcept // prevent QScopedPointer <->QScopedArrayPointer swaps
240 { QScopedPointer<T, Cleanup>::swap(other); }
241
242private:
243 explicit inline QScopedArrayPointer(void *)
244 {
245 // Enforce the same type.
246
247 // If you get a compile error here, make sure you declare
248 // QScopedArrayPointer with the same template type as you pass to the
249 // constructor. See also the QScopedPointer documentation.
250
251 // Storing a scalar array as a pointer to a different type is not
252 // allowed and results in undefined behavior.
253 }
254
255 Q_DISABLE_COPY(QScopedArrayPointer)
256};
257
258template <typename T, typename Cleanup>
259inline void swap(QScopedArrayPointer<T, Cleanup> &lhs, QScopedArrayPointer<T, Cleanup> &rhs) noexcept
260{ lhs.swap(rhs); }
261
262QT_END_NAMESPACE
263
264#endif // QSCOPEDPOINTER_H
265