From cc9c85ecd68c8dae28567dac630f894faaaf1acf Mon Sep 17 00:00:00 2001
From: Olivier Goffart <ogoffart@woboq.com>
Date: Tue, 8 Nov 2011 18:34:47 +0100
Subject: [PATCH] Support for up to 6 arguments in the new connection syntax

For compilations without variadic template support

Change-Id: I78af4f6022ad7a0923e5c5788a34eb7d834f50f3
Reviewed-by: Bradley T. Hughes <bradley.hughes@nokia.com>
---
 doc/src/core/objectmodel/signalsandslots.qdoc |   2 +-
 src/corelib/kernel/qobject_impl.h             | 139 ++++++++++++++++++
 .../corelib/kernel/qobject/tst_qobject.cpp    |   2 -
 3 files changed, 140 insertions(+), 3 deletions(-)

diff --git a/doc/src/core/objectmodel/signalsandslots.qdoc b/doc/src/core/objectmodel/signalsandslots.qdoc
index 175f7e1b07..821147fcfd 100644
--- a/doc/src/core/objectmodel/signalsandslots.qdoc
+++ b/doc/src/core/objectmodel/signalsandslots.qdoc
@@ -396,7 +396,7 @@
     \endcode
 
     Note that if your compiler does not support C++11 variadic templates,
-    this syntax only works if the signal and slot have 3 arguments or less.
+    this syntax only works if the signal and slot have 6 arguments or less.
 
     The other way to connect a signal to a slot is to use QObject::connect()
     and the \c{SIGNAL} and \c{SLOT} macros.
diff --git a/src/corelib/kernel/qobject_impl.h b/src/corelib/kernel/qobject_impl.h
index d34b81ceaf..3c7dacf527 100644
--- a/src/corelib/kernel/qobject_impl.h
+++ b/src/corelib/kernel/qobject_impl.h
@@ -177,6 +177,55 @@ namespace QtPrivate {
                      *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 2>::Value>::Type *>(arg[3])), ApplyReturnValue<R>(arg[0]);
         }
     };
+    template<class Obj, typename Ret, typename Arg1, typename Arg2, typename Arg3, typename Arg4> struct FunctionPointer<Ret (Obj::*) (Arg1, Arg2, Arg3, Arg4)>
+    {
+        typedef Obj Object;
+        typedef List<Arg1, List<Arg2, List<Arg3, List<Arg4, void> > > >  Arguments;
+        typedef Ret ReturnType;
+        typedef Ret (Obj::*Function) (Arg1, Arg2, Arg3, Arg4);
+        enum {ArgumentCount = 4};
+        template <typename Args, typename R>
+        static void call(Function f, Obj *o, void **arg) {
+            (o->*f)( *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 0>::Value>::Type *>(arg[1]),
+                     *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 1>::Value>::Type *>(arg[2]),
+                     *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 2>::Value>::Type *>(arg[3]),
+                     *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 3>::Value>::Type *>(arg[4])), ApplyReturnValue<R>(arg[0]);
+        }
+    };
+    template<class Obj, typename Ret, typename Arg1, typename Arg2, typename Arg3, typename Arg4, typename Arg5> struct FunctionPointer<Ret (Obj::*) (Arg1, Arg2, Arg3, Arg4, Arg5)>
+    {
+        typedef Obj Object;
+        typedef List<Arg1, List<Arg2, List<Arg3, List<Arg4, List<Arg5, void> > > > >  Arguments;
+        typedef Ret ReturnType;
+        typedef Ret (Obj::*Function) (Arg1, Arg2, Arg3, Arg4, Arg5);
+        enum {ArgumentCount = 5};
+        template <typename Args, typename R>
+        static void call(Function f, Obj *o, void **arg) {
+            (o->*f)( *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 0>::Value>::Type *>(arg[1]),
+                     *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 1>::Value>::Type *>(arg[2]),
+                     *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 2>::Value>::Type *>(arg[3]),
+                     *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 3>::Value>::Type *>(arg[4]),
+                     *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 4>::Value>::Type *>(arg[5])), ApplyReturnValue<R>(arg[0]);
+        }
+    };
+    template<class Obj, typename Ret, typename Arg1, typename Arg2, typename Arg3, typename Arg4, typename Arg5, typename Arg6>
+    struct FunctionPointer<Ret (Obj::*) (Arg1, Arg2, Arg3, Arg4, Arg5, Arg6)>
+    {
+        typedef Obj Object;
+        typedef List<Arg1, List<Arg2, List<Arg3, List<Arg4, List<Arg5, List<Arg6, void> > > > > >  Arguments;
+        typedef Ret ReturnType;
+        typedef Ret (Obj::*Function) (Arg1, Arg2, Arg3, Arg4, Arg5, Arg6);
+        enum {ArgumentCount = 6};
+        template <typename Args, typename R>
+        static void call(Function f, Obj *o, void **arg) {
+            (o->*f)( *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 0>::Value>::Type *>(arg[1]),
+                     *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 1>::Value>::Type *>(arg[2]),
+                     *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 2>::Value>::Type *>(arg[3]),
+                     *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 3>::Value>::Type *>(arg[4]),
+                     *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 4>::Value>::Type *>(arg[5]),
+                     *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 5>::Value>::Type *>(arg[6])), ApplyReturnValue<R>(arg[0]);
+        }
+    };
 
     template<typename Ret> struct FunctionPointer<Ret (*) ()>
     {
@@ -221,6 +270,52 @@ namespace QtPrivate {
                      *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 2>::Value>::Type *>(arg[3])), ApplyReturnValue<R>(arg[0]);
         }
     };
+    template<typename Ret, typename Arg1, typename Arg2, typename Arg3, typename Arg4> struct FunctionPointer<Ret (*) (Arg1, Arg2, Arg3, Arg4)>
+    {
+        typedef List<Arg1, List<Arg2, List<Arg3, List<Arg4, void> > > >  Arguments;
+        typedef Ret ReturnType;
+        typedef Ret (*Function) (Arg1, Arg2, Arg3, Arg4);
+        enum {ArgumentCount = 4};
+        template <typename Args, typename R>
+        static void call(Function f, void *, void **arg) {
+            f(       *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 0>::Value>::Type *>(arg[1]),
+                     *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 1>::Value>::Type *>(arg[2]),
+                     *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 2>::Value>::Type *>(arg[3]),
+                     *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 3>::Value>::Type *>(arg[4])), ApplyReturnValue<R>(arg[0]);
+        }
+    };
+    template<typename Ret, typename Arg1, typename Arg2, typename Arg3, typename Arg4, typename Arg5> struct FunctionPointer<Ret (*) (Arg1, Arg2, Arg3, Arg4, Arg5)>
+    {
+        typedef List<Arg1, List<Arg2, List<Arg3,
+        List<Arg4, List<Arg5, void > > > > >  Arguments;
+        typedef Ret ReturnType;
+        typedef Ret (*Function) (Arg1, Arg2, Arg3, Arg4, Arg5);
+        enum {ArgumentCount = 5};
+        template <typename Args, typename R>
+        static void call(Function f, void *, void **arg) {
+            f(       *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 0>::Value>::Type *>(arg[1]),
+                     *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 1>::Value>::Type *>(arg[2]),
+                     *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 2>::Value>::Type *>(arg[3]),
+                     *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 3>::Value>::Type *>(arg[4]),
+                     *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 4>::Value>::Type *>(arg[5])), ApplyReturnValue<R>(arg[0]);
+        }
+    };
+    template<typename Ret, typename Arg1, typename Arg2, typename Arg3, typename Arg4, typename Arg5, typename Arg6> struct FunctionPointer<Ret (*) (Arg1, Arg2, Arg3, Arg4, Arg5, Arg6)>
+    {
+        typedef List<Arg1, List<Arg2, List<Arg3, List<Arg4, List<Arg5, List<Arg6, void> > > > > >  Arguments;
+        typedef Ret ReturnType;
+        typedef Ret (*Function) (Arg1, Arg2, Arg3, Arg4, Arg5, Arg6);
+        enum {ArgumentCount = 6};
+        template <typename Args, typename R>
+        static void call(Function f, void *, void **arg) {
+            f(       *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 0>::Value>::Type *>(arg[1]),
+                     *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 1>::Value>::Type *>(arg[2]),
+                     *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 2>::Value>::Type *>(arg[3]),
+                     *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 3>::Value>::Type *>(arg[4]),
+                     *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 4>::Value>::Type *>(arg[5]),
+                     *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 5>::Value>::Type *>(arg[6])), ApplyReturnValue<R>(arg[0]);
+        }
+    };
 
     template<typename F, int N> struct Functor;
     template<typename Function> struct Functor<Function, 0>
@@ -252,6 +347,39 @@ namespace QtPrivate {
                *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 2>::Value>::Type *>(arg[4])), ApplyReturnValue<R>(arg[0]);
         }
     };
+    template<typename Function> struct Functor<Function, 4>
+    {
+        template <typename Args, typename R>
+        static void call(Function &f, void *, void **arg) {
+            f( *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 0>::Value>::Type *>(arg[1]),
+               *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 1>::Value>::Type *>(arg[2]),
+               *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 2>::Value>::Type *>(arg[3]),
+               *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 3>::Value>::Type *>(arg[4])), ApplyReturnValue<R>(arg[0]);
+        }
+    };
+    template<typename Function> struct Functor<Function, 5>
+    {
+        template <typename Args, typename R>
+        static void call(Function &f, void *, void **arg) {
+            f( *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 0>::Value>::Type *>(arg[1]),
+               *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 1>::Value>::Type *>(arg[2]),
+               *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 2>::Value>::Type *>(arg[3]),
+               *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 3>::Value>::Type *>(arg[4]),
+               *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 4>::Value>::Type *>(arg[5])), ApplyReturnValue<R>(arg[0]);
+        }
+    };
+    template<typename Function> struct Functor<Function, 6>
+    {
+        template <typename Args, typename R>
+        static void call(Function &f, void *, void **arg) {
+            f( *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 0>::Value>::Type *>(arg[1]),
+               *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 1>::Value>::Type *>(arg[2]),
+               *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 2>::Value>::Type *>(arg[3]),
+               *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 3>::Value>::Type *>(arg[4]),
+               *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 4>::Value>::Type *>(arg[5]),
+               *reinterpret_cast<typename RemoveRef<typename List_Select<Args, 5>::Value>::Type *>(arg[6])), ApplyReturnValue<R>(arg[0]);
+        }
+    };
 #else
     template <int...> struct IndexesList {};
     template <typename IndexList, int Right> struct IndexesAppend;
@@ -372,6 +500,17 @@ namespace QtPrivate {
     template <typename Arg1, typename Arg2, typename Arg3> struct ConnectionTypes<List<Arg1, List<Arg2,  List<Arg3, void> > >, true>
     { static const int *types() { static const int t[4] = { QtPrivate::QMetaTypeIdHelper<Arg1>::qt_metatype_id(), QtPrivate::QMetaTypeIdHelper<Arg2>::qt_metatype_id(),
                                                             QtPrivate::QMetaTypeIdHelper<Arg3>::qt_metatype_id(), 0 }; return t; } };
+    template <typename Arg1, typename Arg2, typename Arg3, typename Arg4> struct ConnectionTypes<List<Arg1, List<Arg2,  List<Arg3, List<Arg4, void> > > >, true>
+    { static const int *types() { static const int t[4] = { QtPrivate::QMetaTypeIdHelper<Arg1>::qt_metatype_id(), QtPrivate::QMetaTypeIdHelper<Arg2>::qt_metatype_id(),
+                QtPrivate::QMetaTypeIdHelper<Arg3>::qt_metatype_id(), QtPrivate::QMetaTypeIdHelper<Arg4>::qt_metatype_id(), 0 }; return t; } };
+    template <typename Arg1, typename Arg2, typename Arg3, typename Arg4, typename Arg5> struct ConnectionTypes<List<Arg1, List<Arg2,  List<Arg3, List<Arg4, List<Arg5, void> > > > >, true>
+    { static const int *types() { static const int t[4] = { QtPrivate::QMetaTypeIdHelper<Arg1>::qt_metatype_id(), QtPrivate::QMetaTypeIdHelper<Arg2>::qt_metatype_id(),
+                QtPrivate::QMetaTypeIdHelper<Arg3>::qt_metatype_id(), QtPrivate::QMetaTypeIdHelper<Arg4>::qt_metatype_id(), QtPrivate::QMetaTypeIdHelper<Arg5>::qt_metatype_id(), 0 }; return t; } };
+    template <typename Arg1, typename Arg2, typename Arg3, typename Arg4, typename Arg5, typename Arg6>
+    struct ConnectionTypes<List<Arg1, List<Arg2,  List<Arg3, List<Arg4, List<Arg5, List<Arg6, void> > > > > >, true>
+    { static const int *types() { static const int t[4] = { QtPrivate::QMetaTypeIdHelper<Arg1>::qt_metatype_id(), QtPrivate::QMetaTypeIdHelper<Arg2>::qt_metatype_id(),
+            QtPrivate::QMetaTypeIdHelper<Arg3>::qt_metatype_id(), QtPrivate::QMetaTypeIdHelper<Arg4>::qt_metatype_id(), QtPrivate::QMetaTypeIdHelper<Arg5>::qt_metatype_id(),
+            QtPrivate::QMetaTypeIdHelper<Arg6>::qt_metatype_id(), 0 }; return t; } };
 #else
     template <typename ArgList> struct TypesAreDeclaredMetaType { enum { Value = false }; };
     template <> struct TypesAreDeclaredMetaType<List<>> { enum { Value = true }; };
diff --git a/tests/auto/corelib/kernel/qobject/tst_qobject.cpp b/tests/auto/corelib/kernel/qobject/tst_qobject.cpp
index f5a079fae5..1b5e3bd79e 100644
--- a/tests/auto/corelib/kernel/qobject/tst_qobject.cpp
+++ b/tests/auto/corelib/kernel/qobject/tst_qobject.cpp
@@ -4793,7 +4793,6 @@ namespace ManyArgumentNamespace {
 
 void tst_QObject::connectManyArguments()
 {
-#ifdef Q_COMPILER_VARIADIC_TEMPLATES
     ManyArgumentObject ob;
     ob.count = 0;
     ManyArgumentNamespace::count = 0;
@@ -4841,7 +4840,6 @@ void tst_QObject::connectManyArguments()
     emit ob2.signal6("a", "b", "c", "d", "e", "f");
     QCOMPARE(ob2.count, 6);
     QCOMPARE(ManyArgumentNamespace::count, 6);
-#endif
 }
 
 class ReturnValue : public QObject {