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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{
98 typedef T *QScopedPointer:: *RestrictedBool;
99public:
100 explicit QScopedPointer(T *p = nullptr) Q_DECL_NOTHROW : d(p)
101 {
102 }
103
104 inline ~QScopedPointer()
105 {
106 T *oldD = this->d;
107 Cleanup::cleanup(oldD);
108 }
109
110 inline T &operator*() const
111 {
112 Q_ASSERT(d);
113 return *d;
114 }
115
116 T *operator->() const Q_DECL_NOTHROW
117 {
118 return d;
119 }
120
121 bool operator!() const Q_DECL_NOTHROW
122 {
123 return !d;
124 }
125
126#if defined(Q_QDOC)
127 inline operator bool() const
128 {
129 return isNull() ? nullptr : &QScopedPointer::d;
130 }
131#else
132 operator RestrictedBool() const Q_DECL_NOTHROW
133 {
134 return isNull() ? nullptr : &QScopedPointer::d;
135 }
136#endif
137
138 T *data() const Q_DECL_NOTHROW
139 {
140 return d;
141 }
142
143 T *get() const Q_DECL_NOTHROW
144 {
145 return d;
146 }
147
148 bool isNull() const Q_DECL_NOTHROW
149 {
150 return !d;
151 }
152
153 void reset(T *other = nullptr) Q_DECL_NOEXCEPT_EXPR(noexcept(Cleanup::cleanup(std::declval<T *>())))
154 {
155 if (d == other)
156 return;
157 T *oldD = d;
158 d = other;
159 Cleanup::cleanup(oldD);
160 }
161
162 T *take() Q_DECL_NOTHROW
163 {
164 T *oldD = d;
165 d = nullptr;
166 return oldD;
167 }
168
169 void swap(QScopedPointer<T, Cleanup> &other) Q_DECL_NOTHROW
170 {
171 qSwap(d, other.d);
172 }
173
174 typedef T *pointer;
175
176protected:
177 T *d;
178
179private:
180 Q_DISABLE_COPY(QScopedPointer)
181};
182
183template <class T, class Cleanup>
184inline bool operator==(const QScopedPointer<T, Cleanup> &lhs, const QScopedPointer<T, Cleanup> &rhs) Q_DECL_NOTHROW
185{
186 return lhs.data() == rhs.data();
187}
188
189template <class T, class Cleanup>
190inline bool operator!=(const QScopedPointer<T, Cleanup> &lhs, const QScopedPointer<T, Cleanup> &rhs) Q_DECL_NOTHROW
191{
192 return lhs.data() != rhs.data();
193}
194
195template <class T, class Cleanup>
196inline bool operator==(const QScopedPointer<T, Cleanup> &lhs, std::nullptr_t) Q_DECL_NOTHROW
197{
198 return lhs.isNull();
199}
200
201template <class T, class Cleanup>
202inline bool operator==(std::nullptr_t, const QScopedPointer<T, Cleanup> &rhs) Q_DECL_NOTHROW
203{
204 return rhs.isNull();
205}
206
207template <class T, class Cleanup>
208inline bool operator!=(const QScopedPointer<T, Cleanup> &lhs, std::nullptr_t) Q_DECL_NOTHROW
209{
210 return !lhs.isNull();
211}
212
213template <class T, class Cleanup>
214inline bool operator!=(std::nullptr_t, const QScopedPointer<T, Cleanup> &rhs) Q_DECL_NOTHROW
215{
216 return !rhs.isNull();
217}
218
219template <class T, class Cleanup>
220inline void swap(QScopedPointer<T, Cleanup> &p1, QScopedPointer<T, Cleanup> &p2) Q_DECL_NOTHROW
221{ p1.swap(p2); }
222
223template <typename T, typename Cleanup = QScopedPointerArrayDeleter<T> >
224class QScopedArrayPointer : public QScopedPointer<T, Cleanup>
225{
226 template <typename Ptr>
227 using if_same_type = typename std::enable_if<std::is_same<typename std::remove_cv<T>::type, Ptr>::value, bool>::type;
228public:
229 inline QScopedArrayPointer() : QScopedPointer<T, Cleanup>(nullptr) {}
230
231 template <typename D, if_same_type<D> = true>
232 explicit QScopedArrayPointer(D *p)
233 : QScopedPointer<T, Cleanup>(p)
234 {
235 }
236
237 inline T &operator[](int i)
238 {
239 return this->d[i];
240 }
241
242 inline const T &operator[](int i) const
243 {
244 return this->d[i];
245 }
246
247 void swap(QScopedArrayPointer &other) Q_DECL_NOTHROW // prevent QScopedPointer <->QScopedArrayPointer swaps
248 { QScopedPointer<T, Cleanup>::swap(other); }
249
250private:
251 explicit inline QScopedArrayPointer(void *) {
252 // Enforce the same type.
253
254 // If you get a compile error here, make sure you declare
255 // QScopedArrayPointer with the same template type as you pass to the
256 // constructor. See also the QScopedPointer documentation.
257
258 // Storing a scalar array as a pointer to a different type is not
259 // allowed and results in undefined behavior.
260 }
261
262 Q_DISABLE_COPY(QScopedArrayPointer)
263};
264
265template <typename T, typename Cleanup>
266inline void swap(QScopedArrayPointer<T, Cleanup> &lhs, QScopedArrayPointer<T, Cleanup> &rhs) Q_DECL_NOTHROW
267{ lhs.swap(rhs); }
268
269QT_END_NAMESPACE
270
271#endif // QSCOPEDPOINTER_H
272