diff options
| -rw-r--r-- | src/corelib/tools/qsharedpointer.cpp | 31 | ||||
| -rw-r--r-- | src/corelib/tools/qsharedpointer.h | 3 | ||||
| -rw-r--r-- | src/corelib/tools/qsharedpointer_impl.h | 27 | ||||
| -rw-r--r-- | tests/auto/corelib/tools/qsharedpointer/tst_qsharedpointer.cpp | 120 |
4 files changed, 181 insertions, 0 deletions
diff --git a/src/corelib/tools/qsharedpointer.cpp b/src/corelib/tools/qsharedpointer.cpp index 167771027e..c9456c44c2 100644 --- a/src/corelib/tools/qsharedpointer.cpp +++ b/src/corelib/tools/qsharedpointer.cpp @@ -605,6 +605,37 @@ */ /*! + \fn QSharedPointer<T> QSharedPointer::create() + \since 4.6 + + Creates a QSharedPointer object and allocates a new item of type \tt T. The + QSharedPointer internals and the object are allocated in one single memory + allocation, which could help reduce memory fragmentation in a long-running + application. + + This function calls the default constructor for type \tt T. +*/ + +/*! + \fn QSharedPointer<T> QSharedPointer::create(...) + \overload + \since 5.1 + + Creates a QSharedPointer object and allocates a new item of type \tt T. The + QSharedPointer internals and the object are allocated in one single memory + allocation, which could help reduce memory fragmentation in a long-running + application. + + This function will attempt to call a constructor for type \tt T that can + accept all the arguments passed. Arguments will be perfectly-forwarded. + + \note This function is only available with a C++11 compiler that supports + perfect forwarding of an arbitrary number of arguments. If the compiler + does not support the necessary C++11 features, you must use the overload + that calls the default constructor. +*/ + +/*! \fn QWeakPointer<T> QSharedPointer::toWeakRef() const Returns a weak reference object that shares the pointer referenced diff --git a/src/corelib/tools/qsharedpointer.h b/src/corelib/tools/qsharedpointer.h index cfc5cadbb0..a430153bca 100644 --- a/src/corelib/tools/qsharedpointer.h +++ b/src/corelib/tools/qsharedpointer.h @@ -95,6 +95,9 @@ public: template <class X> QSharedPointer<X> dynamicCast() const; template <class X> QSharedPointer<X> constCast() const; template <class X> QSharedPointer<X> objectCast() const; + + static inline QSharedPointer<T> create(); + static inline QSharedPointer<T> create(...); }; template <class T> diff --git a/src/corelib/tools/qsharedpointer_impl.h b/src/corelib/tools/qsharedpointer_impl.h index 6f3e577e55..6393cc3970 100644 --- a/src/corelib/tools/qsharedpointer_impl.h +++ b/src/corelib/tools/qsharedpointer_impl.h @@ -62,6 +62,10 @@ QT_END_HEADER #include <QtCore/qobject.h> // for qobject_cast #include <QtCore/qhash.h> // for qHash +#if defined(Q_COMPILER_RVALUE_REFS) && defined(Q_COMPILER_VARIADIC_TEMPLATES) +# include <utility> // for std::forward +#endif + QT_BEGIN_HEADER QT_BEGIN_NAMESPACE @@ -389,6 +393,28 @@ public: QWeakPointer<T> toWeakRef() const; +#if defined(Q_COMPILER_RVALUE_REFS) && defined(Q_COMPILER_VARIADIC_TEMPLATES) + template <typename... Args> + static QSharedPointer<T> create(Args && ...arguments) + { + typedef QtSharedPointer::ExternalRefCountWithContiguousData<T> Private; +# ifdef QT_SHAREDPOINTER_TRACK_POINTERS + typename Private::DestroyerFn destroy = &Private::safetyCheckDeleter; +# else + typename Private::DestroyerFn destroy = &Private::deleter; +# endif + QSharedPointer<T> result(Qt::Uninitialized); + result.d = Private::create(&result.value, destroy); + + // now initialize the data + new (result.data()) T(std::forward<Args>(arguments)...); + result.d->setQObjectShared(result.value, true); +# ifdef QT_SHAREDPOINTER_TRACK_POINTERS + internalSafetyCheckAdd(result.d, result.value); +# endif + return result; + } +#else static inline QSharedPointer<T> create() { typedef QtSharedPointer::ExternalRefCountWithContiguousData<T> Private; @@ -408,6 +434,7 @@ public: result.d->setQObjectShared(result.value, true); return result; } +#endif private: explicit QSharedPointer(Qt::Initialization) {} diff --git a/tests/auto/corelib/tools/qsharedpointer/tst_qsharedpointer.cpp b/tests/auto/corelib/tools/qsharedpointer/tst_qsharedpointer.cpp index 9edcb8e787..8dfffebacd 100644 --- a/tests/auto/corelib/tools/qsharedpointer/tst_qsharedpointer.cpp +++ b/tests/auto/corelib/tools/qsharedpointer/tst_qsharedpointer.cpp @@ -95,6 +95,7 @@ private slots: void lambdaCustomDeleter(); #endif void creating(); + void creatingVariadic(); void creatingQObject(); void mixTrackingPointerCode(); void reentrancyWhileDestructing(); @@ -174,6 +175,49 @@ public: int Data::generationCounter = 0; int Data::destructorCounter = 0; +struct NoDefaultConstructor1 +{ + int i; + NoDefaultConstructor1(int i) : i(i) {} + NoDefaultConstructor1(uint j) : i(j + 42) {} +}; + +struct NoDefaultConstructorRef1 +{ + int &i; + NoDefaultConstructorRef1(int &i) : i(i) {} +}; + +struct NoDefaultConstructor2 +{ + void *ptr; + int i; + NoDefaultConstructor2(void *ptr, int i) : ptr(ptr), i(i) {} +}; + +struct NoDefaultConstructorRef2 +{ + QString str; + int i; + NoDefaultConstructorRef2(QString &str, int i) : str(str), i(i) {} +}; + +struct NoDefaultConstructorConstRef2 +{ + QString str; + int i; + NoDefaultConstructorConstRef2(const QString &str, int i) : str(str), i(i) {} + NoDefaultConstructorConstRef2(const QByteArray &ba, int i = 42) : str(QString::fromLatin1(ba)), i(i) {} +}; + +#ifdef Q_COMPILER_RVALUE_REFS +struct NoDefaultConstructorRRef1 +{ + int &i; + NoDefaultConstructorRRef1(int &&i) : i(i) {} +}; +#endif + void tst_QSharedPointer::basics_data() { QTest::addColumn<bool>("isNull"); @@ -1429,6 +1473,82 @@ void tst_QSharedPointer::creating() safetyCheck(); } +void tst_QSharedPointer::creatingVariadic() +{ +#if !defined(Q_COMPILER_RVALUE_REFS) || !defined(Q_COMPILER_VARIADIC_TEMPLATES) + QSKIP("This compiler is not in C++11 mode or it doesn't support rvalue refs and variadic templates"); +#else + int i = 42; + + { + NoDefaultConstructor1(1); // control check + QSharedPointer<NoDefaultConstructor1> ptr = QSharedPointer<NoDefaultConstructor1>::create(1); + QCOMPARE(ptr->i, 1); + + NoDefaultConstructor1(0u); // control check + ptr = QSharedPointer<NoDefaultConstructor1>::create(0u); + QCOMPARE(ptr->i, 42); + + NoDefaultConstructor1 x(i); // control check + ptr = QSharedPointer<NoDefaultConstructor1>::create(i); + QCOMPARE(ptr->i, i); + } + { + NoDefaultConstructor2((void*)0, 1); // control check + QSharedPointer<NoDefaultConstructor2> ptr = QSharedPointer<NoDefaultConstructor2>::create((void*)0, 1); + QCOMPARE(ptr->i, 1); + QCOMPARE(ptr->ptr, (void*)0); + + int *null = 0; + NoDefaultConstructor2(null, 2); // control check + ptr = QSharedPointer<NoDefaultConstructor2>::create(null, 2); + QCOMPARE(ptr->i, 2); + QCOMPARE(ptr->ptr, (void*)0); + +#ifdef Q_COMPILER_NULLPTR + NoDefaultConstructor2(nullptr, 3); // control check + ptr = QSharedPointer<NoDefaultConstructor2>::create(nullptr, 3); + QCOMPARE(ptr->i, 3); + QCOMPARE(ptr->ptr, (void*)nullptr); +#endif + } + { + NoDefaultConstructorRef1 x(i); // control check + QSharedPointer<NoDefaultConstructorRef1> ptr = QSharedPointer<NoDefaultConstructorRef1>::create(i); + QCOMPARE(ptr->i, i); + QCOMPARE(&ptr->i, &i); + } + { + NoDefaultConstructorRRef1(1); // control check + QSharedPointer<NoDefaultConstructorRRef1> ptr = QSharedPointer<NoDefaultConstructorRRef1>::create(1); + QCOMPARE(ptr->i, 1); + + NoDefaultConstructorRRef1(std::move(i)); // control check + ptr = QSharedPointer<NoDefaultConstructorRRef1>::create(std::move(i)); + QCOMPARE(ptr->i, i); + } + { + QString text("Hello, World"); + NoDefaultConstructorRef2(text, 1); // control check + QSharedPointer<NoDefaultConstructorRef2> ptr = QSharedPointer<NoDefaultConstructorRef2>::create(text, 1); + QCOMPARE(ptr->str, text); + QCOMPARE(ptr->i, 1); + } + { + QSharedPointer<NoDefaultConstructorConstRef2> ptr; + NoDefaultConstructorConstRef2(QLatin1String("string"), 1); // control check + ptr = QSharedPointer<NoDefaultConstructorConstRef2>::create(QLatin1String("string"), 1); + QCOMPARE(ptr->str, QString("string")); + QCOMPARE(ptr->i, 1); + + NoDefaultConstructorConstRef2(QByteArray("bytearray")); // control check + ptr = QSharedPointer<NoDefaultConstructorConstRef2>::create(QByteArray("bytearray")); + QCOMPARE(ptr->str, QString("bytearray")); + QCOMPARE(ptr->i, 42); + } +#endif +} + void tst_QSharedPointer::creatingQObject() { { |