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39 
40 #ifndef QTCONCURRENT_RUNBASE_H
41 #define QTCONCURRENT_RUNBASE_H
42 
43 #include <QtConcurrent/qtconcurrent_global.h>
44 
45 #ifndef QT_NO_CONCURRENT
46 
47 #include <QtCore/qfuture.h>
48 #include <QtCore/qrunnable.h>
49 #include <QtCore/qthreadpool.h>
50 
51 QT_BEGIN_NAMESPACE
52 
53 
54 #ifndef Q_QDOC
55 
56 namespace QtConcurrent {
57 
58 template <typename T>
59 struct SelectSpecialization
60 {
61     template <class Normal, class Void>
62     struct Type { typedef Normal type; };
63 };
64 
65 template <>
66 struct SelectSpecialization<void>
67 {
68     template <class Normal, class Void>
69     struct Type { typedef Void type; };
70 };
71 
72 template <typename T>
73 class RunFunctionTaskBase : public QFutureInterface<T> , public QRunnable
74 {
75 public:
76     QFuture<T> start()
77     {
78         return start(QThreadPool::globalInstance());
79     }
80 
81     QFuture<T> start(QThreadPool *pool)
82     {
83         this->setThreadPool(pool);
84         this->setRunnable(this);
85         this->reportStarted();
86         QFuture<T> theFuture = this->future();
87         pool->start(this, /*m_priority*/ 0);
88         return theFuture;
89     }
90 
91     void run() override {}
92     virtual void runFunctor() = 0;
93 };
94 
95 template <typename T>
96 class RunFunctionTask : public RunFunctionTaskBase<T>
97 {
98 public:
99     void run() override
100     {
101         if (this->isCanceled()) {
102             this->reportFinished();
103             return;
104         }
105 #ifndef QT_NO_EXCEPTIONS
106         try {
107 #endif
108             this->runFunctor();
109 #ifndef QT_NO_EXCEPTIONS
110         } catch (QException &e) {
111             QFutureInterface<T>::reportException(e);
112         } catch (...) {
113             QFutureInterface<T>::reportException(QUnhandledException());
114         }
115 #endif
116 
117         this->reportResult(result);
118         this->reportFinished();
119     }
120     T result;
121 };
122 
123 template <>
124 class RunFunctionTask<void> : public RunFunctionTaskBase<void>
125 {
126 public:
127     void run() override
128     {
129         if (this->isCanceled()) {
130             this->reportFinished();
131             return;
132         }
133 #ifndef QT_NO_EXCEPTIONS
134         try {
135 #endif
136             this->runFunctor();
137 #ifndef QT_NO_EXCEPTIONS
138         } catch (QException &e) {
139             QFutureInterface<void>::reportException(e);
140         } catch (...) {
141             QFutureInterface<void>::reportException(QUnhandledException());
142         }
143 #endif
144         this->reportFinished();
145     }
146 };
147 
148 } //namespace QtConcurrent
149 
150 #endif //Q_QDOC
151 
152 QT_END_NAMESPACE
153 
154 #endif // QT_NO_CONCURRENT
155 
156 #endif
157