| /**************************************************************************** |
| ** |
| ** Copyright (C) 2016 The Qt Company Ltd. |
| ** Copyright (C) 2013 Olivier Goffart <ogoffart@woboq.com> |
| ** Contact: https://www.qt.io/licensing/ |
| ** |
| ** This file is part of the QtCore module of the Qt Toolkit. |
| ** |
| ** $QT_BEGIN_LICENSE:LGPL$ |
| ** Commercial License Usage |
| ** Licensees holding valid commercial Qt licenses may use this file in |
| ** accordance with the commercial license agreement provided with the |
| ** Software or, alternatively, in accordance with the terms contained in |
| ** a written agreement between you and The Qt Company. For licensing terms |
| ** and conditions see https://www.qt.io/terms-conditions. For further |
| ** information use the contact form at https://www.qt.io/contact-us. |
| ** |
| ** GNU Lesser General Public License Usage |
| ** Alternatively, this file may be used under the terms of the GNU Lesser |
| ** General Public License version 3 as published by the Free Software |
| ** Foundation and appearing in the file LICENSE.LGPL3 included in the |
| ** packaging of this file. Please review the following information to |
| ** ensure the GNU Lesser General Public License version 3 requirements |
| ** will be met: https://www.gnu.org/licenses/lgpl-3.0.html. |
| ** |
| ** GNU General Public License Usage |
| ** Alternatively, this file may be used under the terms of the GNU |
| ** General Public License version 2.0 or (at your option) the GNU General |
| ** Public license version 3 or any later version approved by the KDE Free |
| ** Qt Foundation. The licenses are as published by the Free Software |
| ** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3 |
| ** included in the packaging of this file. Please review the following |
| ** information to ensure the GNU General Public License requirements will |
| ** be met: https://www.gnu.org/licenses/gpl-2.0.html and |
| ** https://www.gnu.org/licenses/gpl-3.0.html. |
| ** |
| ** $QT_END_LICENSE$ |
| ** |
| ****************************************************************************/ |
| |
| #ifndef QOBJECTDEFS_H |
| #error Do not include qobjectdefs_impl.h directly |
| #include <QtCore/qnamespace.h> |
| #endif |
| |
| #if 0 |
| #pragma qt_sync_skip_header_check |
| #pragma qt_sync_stop_processing |
| #endif |
| |
| QT_BEGIN_NAMESPACE |
| class QObject; |
| |
| namespace QtPrivate { |
| template <typename T> struct RemoveRef { typedef T Type; }; |
| template <typename T> struct RemoveRef<T&> { typedef T Type; }; |
| template <typename T> struct RemoveConstRef { typedef T Type; }; |
| template <typename T> struct RemoveConstRef<const T&> { typedef T Type; }; |
| |
| /* |
| The following List classes are used to help to handle the list of arguments. |
| It follow the same principles as the lisp lists. |
| List_Left<L,N> take a list and a number as a parameter and returns (via the Value typedef, |
| the list composed of the first N element of the list |
| */ |
| // With variadic template, lists are represented using a variadic template argument instead of the lisp way |
| template <typename...> struct List {}; |
| template <typename Head, typename... Tail> struct List<Head, Tail...> { typedef Head Car; typedef List<Tail...> Cdr; }; |
| template <typename, typename> struct List_Append; |
| template <typename... L1, typename...L2> struct List_Append<List<L1...>, List<L2...>> { typedef List<L1..., L2...> Value; }; |
| template <typename L, int N> struct List_Left { |
| typedef typename List_Append<List<typename L::Car>,typename List_Left<typename L::Cdr, N - 1>::Value>::Value Value; |
| }; |
| template <typename L> struct List_Left<L, 0> { typedef List<> Value; }; |
| // List_Select<L,N> returns (via typedef Value) the Nth element of the list L |
| template <typename L, int N> struct List_Select { typedef typename List_Select<typename L::Cdr, N - 1>::Value Value; }; |
| template <typename L> struct List_Select<L,0> { typedef typename L::Car Value; }; |
| |
| /* |
| trick to set the return value of a slot that works even if the signal or the slot returns void |
| to be used like function(), ApplyReturnValue<ReturnType>(&return_value) |
| if function() returns a value, the operator,(T, ApplyReturnValue<ReturnType>) is called, but if it |
| returns void, the builtin one is used without an error. |
| */ |
| template <typename T> |
| struct ApplyReturnValue { |
| void *data; |
| explicit ApplyReturnValue(void *data_) : data(data_) {} |
| }; |
| template<typename T, typename U> |
| void operator,(T &&value, const ApplyReturnValue<U> &container) { |
| if (container.data) |
| *reinterpret_cast<U *>(container.data) = std::forward<T>(value); |
| } |
| template<typename T> |
| void operator,(T, const ApplyReturnValue<void> &) {} |
| |
| |
| /* |
| The FunctionPointer<Func> struct is a type trait for function pointer. |
| - ArgumentCount is the number of argument, or -1 if it is unknown |
| - the Object typedef is the Object of a pointer to member function |
| - the Arguments typedef is the list of argument (in a QtPrivate::List) |
| - the Function typedef is an alias to the template parameter Func |
| - the call<Args, R>(f,o,args) method is used to call that slot |
| Args is the list of argument of the signal |
| R is the return type of the signal |
| f is the function pointer |
| o is the receiver object |
| and args is the array of pointer to arguments, as used in qt_metacall |
| |
| The Functor<Func,N> struct is the helper to call a functor of N argument. |
| its call function is the same as the FunctionPointer::call function. |
| */ |
| template<class T> using InvokeGenSeq = typename T::Type; |
| |
| template<int...> struct IndexesList { using Type = IndexesList; }; |
| |
| template<int N, class S1, class S2> struct ConcatSeqImpl; |
| |
| template<int N, int... I1, int... I2> |
| struct ConcatSeqImpl<N, IndexesList<I1...>, IndexesList<I2...>> |
| : IndexesList<I1..., (N + I2)...>{}; |
| |
| template<int N, class S1, class S2> |
| using ConcatSeq = InvokeGenSeq<ConcatSeqImpl<N, S1, S2>>; |
| |
| template<int N> struct GenSeq; |
| template<int N> using makeIndexSequence = InvokeGenSeq<GenSeq<N>>; |
| |
| template<int N> |
| struct GenSeq : ConcatSeq<N/2, makeIndexSequence<N/2>, makeIndexSequence<N - N/2>>{}; |
| |
| template<> struct GenSeq<0> : IndexesList<>{}; |
| template<> struct GenSeq<1> : IndexesList<0>{}; |
| |
| template<int N> |
| struct Indexes { using Value = makeIndexSequence<N>; }; |
| |
| template<typename Func> struct FunctionPointer { enum {ArgumentCount = -1, IsPointerToMemberFunction = false}; }; |
| |
| template <typename, typename, typename, typename> struct FunctorCall; |
| template <int... II, typename... SignalArgs, typename R, typename Function> |
| struct FunctorCall<IndexesList<II...>, List<SignalArgs...>, R, Function> { |
| static void call(Function &f, void **arg) { |
| f((*reinterpret_cast<typename RemoveRef<SignalArgs>::Type *>(arg[II+1]))...), ApplyReturnValue<R>(arg[0]); |
| } |
| }; |
| template <int... II, typename... SignalArgs, typename R, typename... SlotArgs, typename SlotRet, class Obj> |
| struct FunctorCall<IndexesList<II...>, List<SignalArgs...>, R, SlotRet (Obj::*)(SlotArgs...)> { |
| static void call(SlotRet (Obj::*f)(SlotArgs...), Obj *o, void **arg) { |
| (o->*f)((*reinterpret_cast<typename RemoveRef<SignalArgs>::Type *>(arg[II+1]))...), ApplyReturnValue<R>(arg[0]); |
| } |
| }; |
| template <int... II, typename... SignalArgs, typename R, typename... SlotArgs, typename SlotRet, class Obj> |
| struct FunctorCall<IndexesList<II...>, List<SignalArgs...>, R, SlotRet (Obj::*)(SlotArgs...) const> { |
| static void call(SlotRet (Obj::*f)(SlotArgs...) const, Obj *o, void **arg) { |
| (o->*f)((*reinterpret_cast<typename RemoveRef<SignalArgs>::Type *>(arg[II+1]))...), ApplyReturnValue<R>(arg[0]); |
| } |
| }; |
| #if defined(__cpp_noexcept_function_type) && __cpp_noexcept_function_type >= 201510 |
| template <int... II, typename... SignalArgs, typename R, typename... SlotArgs, typename SlotRet, class Obj> |
| struct FunctorCall<IndexesList<II...>, List<SignalArgs...>, R, SlotRet (Obj::*)(SlotArgs...) noexcept> { |
| static void call(SlotRet (Obj::*f)(SlotArgs...) noexcept, Obj *o, void **arg) { |
| (o->*f)((*reinterpret_cast<typename RemoveRef<SignalArgs>::Type *>(arg[II+1]))...), ApplyReturnValue<R>(arg[0]); |
| } |
| }; |
| template <int... II, typename... SignalArgs, typename R, typename... SlotArgs, typename SlotRet, class Obj> |
| struct FunctorCall<IndexesList<II...>, List<SignalArgs...>, R, SlotRet (Obj::*)(SlotArgs...) const noexcept> { |
| static void call(SlotRet (Obj::*f)(SlotArgs...) const noexcept, Obj *o, void **arg) { |
| (o->*f)((*reinterpret_cast<typename RemoveRef<SignalArgs>::Type *>(arg[II+1]))...), ApplyReturnValue<R>(arg[0]); |
| } |
| }; |
| #endif |
| |
| template<class Obj, typename Ret, typename... Args> struct FunctionPointer<Ret (Obj::*) (Args...)> |
| { |
| typedef Obj Object; |
| typedef List<Args...> Arguments; |
| typedef Ret ReturnType; |
| typedef Ret (Obj::*Function) (Args...); |
| enum {ArgumentCount = sizeof...(Args), IsPointerToMemberFunction = true}; |
| template <typename SignalArgs, typename R> |
| static void call(Function f, Obj *o, void **arg) { |
| FunctorCall<typename Indexes<ArgumentCount>::Value, SignalArgs, R, Function>::call(f, o, arg); |
| } |
| }; |
| template<class Obj, typename Ret, typename... Args> struct FunctionPointer<Ret (Obj::*) (Args...) const> |
| { |
| typedef Obj Object; |
| typedef List<Args...> Arguments; |
| typedef Ret ReturnType; |
| typedef Ret (Obj::*Function) (Args...) const; |
| enum {ArgumentCount = sizeof...(Args), IsPointerToMemberFunction = true}; |
| template <typename SignalArgs, typename R> |
| static void call(Function f, Obj *o, void **arg) { |
| FunctorCall<typename Indexes<ArgumentCount>::Value, SignalArgs, R, Function>::call(f, o, arg); |
| } |
| }; |
| |
| template<typename Ret, typename... Args> struct FunctionPointer<Ret (*) (Args...)> |
| { |
| typedef List<Args...> Arguments; |
| typedef Ret ReturnType; |
| typedef Ret (*Function) (Args...); |
| enum {ArgumentCount = sizeof...(Args), IsPointerToMemberFunction = false}; |
| template <typename SignalArgs, typename R> |
| static void call(Function f, void *, void **arg) { |
| FunctorCall<typename Indexes<ArgumentCount>::Value, SignalArgs, R, Function>::call(f, arg); |
| } |
| }; |
| |
| #if defined(__cpp_noexcept_function_type) && __cpp_noexcept_function_type >= 201510 |
| template<class Obj, typename Ret, typename... Args> struct FunctionPointer<Ret (Obj::*) (Args...) noexcept> |
| { |
| typedef Obj Object; |
| typedef List<Args...> Arguments; |
| typedef Ret ReturnType; |
| typedef Ret (Obj::*Function) (Args...) noexcept; |
| enum {ArgumentCount = sizeof...(Args), IsPointerToMemberFunction = true}; |
| template <typename SignalArgs, typename R> |
| static void call(Function f, Obj *o, void **arg) { |
| FunctorCall<typename Indexes<ArgumentCount>::Value, SignalArgs, R, Function>::call(f, o, arg); |
| } |
| }; |
| template<class Obj, typename Ret, typename... Args> struct FunctionPointer<Ret (Obj::*) (Args...) const noexcept> |
| { |
| typedef Obj Object; |
| typedef List<Args...> Arguments; |
| typedef Ret ReturnType; |
| typedef Ret (Obj::*Function) (Args...) const noexcept; |
| enum {ArgumentCount = sizeof...(Args), IsPointerToMemberFunction = true}; |
| template <typename SignalArgs, typename R> |
| static void call(Function f, Obj *o, void **arg) { |
| FunctorCall<typename Indexes<ArgumentCount>::Value, SignalArgs, R, Function>::call(f, o, arg); |
| } |
| }; |
| |
| template<typename Ret, typename... Args> struct FunctionPointer<Ret (*) (Args...) noexcept> |
| { |
| typedef List<Args...> Arguments; |
| typedef Ret ReturnType; |
| typedef Ret (*Function) (Args...) noexcept; |
| enum {ArgumentCount = sizeof...(Args), IsPointerToMemberFunction = false}; |
| template <typename SignalArgs, typename R> |
| static void call(Function f, void *, void **arg) { |
| FunctorCall<typename Indexes<ArgumentCount>::Value, SignalArgs, R, Function>::call(f, arg); |
| } |
| }; |
| #endif |
| |
| template<typename Function, int N> struct Functor |
| { |
| template <typename SignalArgs, typename R> |
| static void call(Function &f, void *, void **arg) { |
| FunctorCall<typename Indexes<N>::Value, SignalArgs, R, Function>::call(f, arg); |
| } |
| }; |
| |
| /* |
| Logic that checks if the underlying type of an enum is signed or not. |
| Needs an external, explicit check that E is indeed an enum. Works |
| around the fact that it's undefined behavior to instantiate |
| std::underlying_type on non-enums (cf. §20.13.7.6 [meta.trans.other]). |
| */ |
| template<typename E, typename Enable = void> |
| struct IsEnumUnderlyingTypeSigned : std::false_type |
| { |
| }; |
| |
| template<typename E> |
| struct IsEnumUnderlyingTypeSigned<E, typename std::enable_if<std::is_enum<E>::value>::type> |
| : std::integral_constant<bool, std::is_signed<typename std::underlying_type<E>::type>::value> |
| { |
| }; |
| |
| /* |
| Logic that checks if the argument of the slot does not narrow the |
| argument of the signal when used in list initialization. Cf. §8.5.4.7 |
| [dcl.init.list] for the definition of narrowing. |
| For incomplete From/To types, there's no narrowing. |
| */ |
| template<typename From, typename To, typename Enable = void> |
| struct AreArgumentsNarrowedBase : std::false_type |
| { |
| }; |
| |
| template<typename From, typename To> |
| struct AreArgumentsNarrowedBase<From, To, typename std::enable_if<sizeof(From) && sizeof(To)>::type> |
| : std::integral_constant<bool, |
| (std::is_floating_point<From>::value && std::is_integral<To>::value) || |
| (std::is_floating_point<From>::value && std::is_floating_point<To>::value && sizeof(From) > sizeof(To)) || |
| ((std::is_integral<From>::value || std::is_enum<From>::value) && std::is_floating_point<To>::value) || |
| (std::is_integral<From>::value && std::is_integral<To>::value |
| && (sizeof(From) > sizeof(To) |
| || (std::is_signed<From>::value ? !std::is_signed<To>::value |
| : (std::is_signed<To>::value && sizeof(From) == sizeof(To))))) || |
| (std::is_enum<From>::value && std::is_integral<To>::value |
| && (sizeof(From) > sizeof(To) |
| || (IsEnumUnderlyingTypeSigned<From>::value ? !std::is_signed<To>::value |
| : (std::is_signed<To>::value && sizeof(From) == sizeof(To))))) |
| > |
| { |
| }; |
| |
| /* |
| Logic that check if the arguments of the slot matches the argument of the signal. |
| To be used like this: |
| Q_STATIC_ASSERT(CheckCompatibleArguments<FunctionPointer<Signal>::Arguments, FunctionPointer<Slot>::Arguments>::value) |
| */ |
| template<typename A1, typename A2> struct AreArgumentsCompatible { |
| static int test(const typename RemoveRef<A2>::Type&); |
| static char test(...); |
| static const typename RemoveRef<A1>::Type &dummy(); |
| enum { value = sizeof(test(dummy())) == sizeof(int) }; |
| #ifdef QT_NO_NARROWING_CONVERSIONS_IN_CONNECT |
| using AreArgumentsNarrowed = AreArgumentsNarrowedBase<typename RemoveRef<A1>::Type, typename RemoveRef<A2>::Type>; |
| Q_STATIC_ASSERT_X(!AreArgumentsNarrowed::value, "Signal and slot arguments are not compatible (narrowing)"); |
| #endif |
| }; |
| template<typename A1, typename A2> struct AreArgumentsCompatible<A1, A2&> { enum { value = false }; }; |
| template<typename A> struct AreArgumentsCompatible<A&, A&> { enum { value = true }; }; |
| // void as a return value |
| template<typename A> struct AreArgumentsCompatible<void, A> { enum { value = true }; }; |
| template<typename A> struct AreArgumentsCompatible<A, void> { enum { value = true }; }; |
| template<> struct AreArgumentsCompatible<void, void> { enum { value = true }; }; |
| |
| template <typename List1, typename List2> struct CheckCompatibleArguments { enum { value = false }; }; |
| template <> struct CheckCompatibleArguments<List<>, List<>> { enum { value = true }; }; |
| template <typename List1> struct CheckCompatibleArguments<List1, List<>> { enum { value = true }; }; |
| template <typename Arg1, typename Arg2, typename... Tail1, typename... Tail2> |
| struct CheckCompatibleArguments<List<Arg1, Tail1...>, List<Arg2, Tail2...>> |
| { |
| enum { value = AreArgumentsCompatible<typename RemoveConstRef<Arg1>::Type, typename RemoveConstRef<Arg2>::Type>::value |
| && CheckCompatibleArguments<List<Tail1...>, List<Tail2...>>::value }; |
| }; |
| |
| /* |
| Find the maximum number of arguments a functor object can take and be still compatible with |
| the arguments from the signal. |
| Value is the number of arguments, or -1 if nothing matches. |
| */ |
| template <typename Functor, typename ArgList> struct ComputeFunctorArgumentCount; |
| |
| template <typename Functor, typename ArgList, bool Done> struct ComputeFunctorArgumentCountHelper |
| { enum { Value = -1 }; }; |
| template <typename Functor, typename First, typename... ArgList> |
| struct ComputeFunctorArgumentCountHelper<Functor, List<First, ArgList...>, false> |
| : ComputeFunctorArgumentCount<Functor, |
| typename List_Left<List<First, ArgList...>, sizeof...(ArgList)>::Value> {}; |
| |
| template <typename Functor, typename... ArgList> struct ComputeFunctorArgumentCount<Functor, List<ArgList...>> |
| { |
| template <typename D> static D dummy(); |
| template <typename F> static auto test(F f) -> decltype(((f.operator()((dummy<ArgList>())...)), int())); |
| static char test(...); |
| enum { |
| Ok = sizeof(test(dummy<Functor>())) == sizeof(int), |
| Value = Ok ? int(sizeof...(ArgList)) : int(ComputeFunctorArgumentCountHelper<Functor, List<ArgList...>, Ok>::Value) |
| }; |
| }; |
| |
| /* get the return type of a functor, given the signal argument list */ |
| template <typename Functor, typename ArgList> struct FunctorReturnType; |
| template <typename Functor, typename ... ArgList> struct FunctorReturnType<Functor, List<ArgList...>> { |
| template <typename D> static D dummy(); |
| typedef decltype(dummy<Functor>().operator()((dummy<ArgList>())...)) Value; |
| }; |
| |
| // internal base class (interface) containing functions required to call a slot managed by a pointer to function. |
| class QSlotObjectBase { |
| QAtomicInt m_ref; |
| // don't use virtual functions here; we don't want the |
| // compiler to create tons of per-polymorphic-class stuff that |
| // we'll never need. We just use one function pointer. |
| typedef void (*ImplFn)(int which, QSlotObjectBase* this_, QObject *receiver, void **args, bool *ret); |
| const ImplFn m_impl; |
| protected: |
| enum Operation { |
| Destroy, |
| Call, |
| Compare, |
| |
| NumOperations |
| }; |
| public: |
| explicit QSlotObjectBase(ImplFn fn) : m_ref(1), m_impl(fn) {} |
| |
| inline int ref() noexcept { return m_ref.ref(); } |
| inline void destroyIfLastRef() noexcept |
| { if (!m_ref.deref()) m_impl(Destroy, this, nullptr, nullptr, nullptr); } |
| |
| inline bool compare(void **a) { bool ret = false; m_impl(Compare, this, nullptr, a, &ret); return ret; } |
| inline void call(QObject *r, void **a) { m_impl(Call, this, r, a, nullptr); } |
| protected: |
| ~QSlotObjectBase() {} |
| private: |
| Q_DISABLE_COPY_MOVE(QSlotObjectBase) |
| }; |
| |
| // implementation of QSlotObjectBase for which the slot is a pointer to member function of a QObject |
| // Args and R are the List of arguments and the returntype of the signal to which the slot is connected. |
| template<typename Func, typename Args, typename R> class QSlotObject : public QSlotObjectBase |
| { |
| typedef QtPrivate::FunctionPointer<Func> FuncType; |
| Func function; |
| static void impl(int which, QSlotObjectBase *this_, QObject *r, void **a, bool *ret) |
| { |
| switch (which) { |
| case Destroy: |
| delete static_cast<QSlotObject*>(this_); |
| break; |
| case Call: |
| FuncType::template call<Args, R>(static_cast<QSlotObject*>(this_)->function, static_cast<typename FuncType::Object *>(r), a); |
| break; |
| case Compare: |
| *ret = *reinterpret_cast<Func *>(a) == static_cast<QSlotObject*>(this_)->function; |
| break; |
| case NumOperations: ; |
| } |
| } |
| public: |
| explicit QSlotObject(Func f) : QSlotObjectBase(&impl), function(f) {} |
| }; |
| // implementation of QSlotObjectBase for which the slot is a functor (or lambda) |
| // N is the number of arguments |
| // Args and R are the List of arguments and the returntype of the signal to which the slot is connected. |
| template<typename Func, int N, typename Args, typename R> class QFunctorSlotObject : public QSlotObjectBase |
| { |
| typedef QtPrivate::Functor<Func, N> FuncType; |
| Func function; |
| static void impl(int which, QSlotObjectBase *this_, QObject *r, void **a, bool *ret) |
| { |
| switch (which) { |
| case Destroy: |
| delete static_cast<QFunctorSlotObject*>(this_); |
| break; |
| case Call: |
| FuncType::template call<Args, R>(static_cast<QFunctorSlotObject*>(this_)->function, r, a); |
| break; |
| case Compare: // not implemented |
| case NumOperations: |
| Q_UNUSED(ret); |
| } |
| } |
| public: |
| explicit QFunctorSlotObject(Func f) : QSlotObjectBase(&impl), function(std::move(f)) {} |
| }; |
| |
| // typedefs for readability for when there are no parameters |
| template <typename Func> |
| using QSlotObjectWithNoArgs = QSlotObject<Func, |
| QtPrivate::List<>, |
| typename QtPrivate::FunctionPointer<Func>::ReturnType>; |
| |
| template <typename Func, typename R> |
| using QFunctorSlotObjectWithNoArgs = QFunctorSlotObject<Func, 0, QtPrivate::List<>, R>; |
| |
| template <typename Func> |
| using QFunctorSlotObjectWithNoArgsImplicitReturn = QFunctorSlotObjectWithNoArgs<Func, typename QtPrivate::FunctionPointer<Func>::ReturnType>; |
| } |
| |
| QT_END_NAMESPACE |
| |