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39
40#ifndef QARRAYDATAPOINTER_H
41#define QARRAYDATAPOINTER_H
42
43#include <QtCore/qarraydataops.h>
44
45QT_BEGIN_NAMESPACE
46
47template <class T>
48struct QArrayDataPointer
49{
50private:
51 typedef QTypedArrayData<T> Data;
52 typedef QArrayDataOps<T> DataOps;
53
54public:
55 QArrayDataPointer() noexcept
56 : d(Data::sharedNull())
57 {
58 }
59
60 QArrayDataPointer(const QArrayDataPointer &other)
61 : d(other.d->ref.ref()
62 ? other.d
63 : other.clone(other.d->cloneFlags()))
64 {
65 }
66
67 explicit QArrayDataPointer(QTypedArrayData<T> *ptr)
68 : d(ptr)
69 {
70 Q_CHECK_PTR(ptr);
71 }
72
73 QArrayDataPointer(QArrayDataPointerRef<T> ref)
74 : d(ref.ptr)
75 {
76 }
77
78 QArrayDataPointer &operator=(const QArrayDataPointer &other)
79 {
80 QArrayDataPointer tmp(other);
81 this->swap(tmp);
82 return *this;
83 }
84
85 QArrayDataPointer(QArrayDataPointer &&other) noexcept
86 : d(other.d)
87 {
88 other.d = Data::sharedNull();
89 }
90
91 QArrayDataPointer &operator=(QArrayDataPointer &&other) noexcept
92 {
93 QArrayDataPointer moved(std::move(other));
94 this->swap(moved);
95 return *this;
96 }
97
98 DataOps &operator*() const
99 {
100 Q_ASSERT(d);
101 return *static_cast<DataOps *>(d);
102 }
103
104 DataOps *operator->() const
105 {
106 Q_ASSERT(d);
107 return static_cast<DataOps *>(d);
108 }
109
110 ~QArrayDataPointer()
111 {
112 if (!d->ref.deref()) {
113 if (d->isMutable())
114 (*this)->destroyAll();
115 Data::deallocate(d);
116 }
117 }
118
119 bool isNull() const
120 {
121 return d == Data::sharedNull();
122 }
123
124 Data *data() const
125 {
126 return d;
127 }
128
129 bool needsDetach() const
130 {
131 return (!d->isMutable() || d->ref.isShared());
132 }
133
134#if !defined(QT_NO_UNSHARABLE_CONTAINERS)
135 void setSharable(bool sharable)
136 {
137 if (needsDetach()) {
138 Data *detached = clone(sharable
139 ? d->detachFlags() & ~QArrayData::Unsharable
140 : d->detachFlags() | QArrayData::Unsharable);
141 QArrayDataPointer old(d);
142 d = detached;
143 } else {
144 d->ref.setSharable(sharable);
145 }
146 }
147
148 bool isSharable() const { return d->isSharable(); }
149#endif
150
151 void swap(QArrayDataPointer &other) noexcept
152 {
153 qSwap(d, other.d);
154 }
155
156 void clear()
157 {
158 QArrayDataPointer tmp(d);
159 d = Data::sharedNull();
160 }
161
162 bool detach()
163 {
164 if (needsDetach()) {
165 Data *copy = clone(d->detachFlags());
166 QArrayDataPointer old(d);
167 d = copy;
168 return true;
169 }
170
171 return false;
172 }
173
174private:
175 Q_REQUIRED_RESULT Data *clone(QArrayData::AllocationOptions options) const
176 {
177 Data *x = Data::allocate(d->detachCapacity(d->size), options);
178 Q_CHECK_PTR(x);
179 QArrayDataPointer copy(x);
180
181 if (d->size)
182 copy->copyAppend(d->begin(), d->end());
183
184 Data *result = copy.d;
185 copy.d = Data::sharedNull();
186 return result;
187 }
188
189 Data *d;
190};
191
192template <class T>
193inline bool operator==(const QArrayDataPointer<T> &lhs, const QArrayDataPointer<T> &rhs)
194{
195 return lhs.data() == rhs.data();
196}
197
198template <class T>
199inline bool operator!=(const QArrayDataPointer<T> &lhs, const QArrayDataPointer<T> &rhs)
200{
201 return lhs.data() != rhs.data();
202}
203
204template <class T>
205inline void swap(QArrayDataPointer<T> &p1, QArrayDataPointer<T> &p2)
206{
207 p1.swap(p2);
208}
209
210QT_END_NAMESPACE
211
212#endif // include guard
213