Fix void pointers

rice/Data_Object.ipp

@@ -190,6 +190,36 @@ namespace Rice::detail
     Return* returnInfo_ = nullptr;
   };
 
+  template <>
+  class To_Ruby<void*>
+  {
+  public:
+    To_Ruby() = default;
+
+    explicit To_Ruby(Return* returnInfo) : returnInfo_(returnInfo)
+    {
+    }
+
+    VALUE convert(void* data)
+    {
+      if (data)
+      {
+        // Note that T could be a pointer or reference to a base class while data is in fact a
+        // child class. Lookup the correct type so we return an instance of the correct Ruby class
+        std::pair<VALUE, rb_data_type_t*> rubyTypeInfo = detail::Registries::instance.types.figureType(data);
+        bool isOwner = this->returnInfo_ && this->returnInfo_->isOwner();
+        return detail::wrap(rubyTypeInfo.first, rubyTypeInfo.second, data, isOwner);
+      }
+      else
+      {
+        return Qnil;
+      }
+    }
+
+  private:
+    Return* returnInfo_ = nullptr;
+  };
+
   template <typename T>
   class To_Ruby<T*&>
   {
@@ -452,5 +482,47 @@ namespace Rice::detail
       return Data_Object<T>(value);
     }
   };
+
+  template<>
+  class From_Ruby<void*>
+  {
+  public:
+    Convertible is_convertible(VALUE value)
+    {
+      switch (rb_type(value))
+      {
+        case RUBY_T_DATA:
+          // Hope for the best!
+          return Convertible::Exact;
+          break;
+        case RUBY_T_NIL:
+          return Convertible::Exact;
+          break;
+        default:
+          return Convertible::None;
+      }
+    }
+
+    void* convert(VALUE value)
+    {
+      switch (rb_type(value))
+      {
+        case RUBY_T_DATA:
+        {
+          // Since C++ is not telling us type information, we need to extract it
+          // from the Ruby object.
+          const rb_data_type_t* rb_type = RTYPEDDATA_TYPE(value);
+          return detail::unwrap<void>(value, (rb_data_type_t*)rb_type);
+          break;
+        }
+        case RUBY_T_NIL:
+          return nullptr;
+          break;
+        default:
+          throw Exception(rb_eTypeError, "wrong argument type %s (expected % s)",
+            detail::protect(rb_obj_classname, value), "pointer");
+      }
+    }
+  };
 }
 #endif // Rice__Data_Object__ipp_

rice/Data_Type.ipp

@@ -19,7 +19,7 @@
 namespace Rice
 {
   template<typename T>
-  void ruby_mark_internal(detail::Wrapper* wrapper)
+  inline void ruby_mark_internal(detail::Wrapper* wrapper)
   {
     // Tell the wrapper to mark the objects its keeping alive
     wrapper->ruby_mark();
@@ -30,17 +30,23 @@ namespace Rice
   }
 
   template<typename T>
-  void ruby_free_internal(detail::Wrapper* wrapper)
+  inline void ruby_free_internal(detail::Wrapper* wrapper)
   {
     delete wrapper;
   }
 
   template<typename T>
-  size_t ruby_size_internal(const T* data)
+  inline size_t ruby_size_internal(const T* data)
   {
     return sizeof(T);
   }
 
+  template<>
+  inline size_t ruby_size_internal(const void* data)
+  {
+    return sizeof(void*);
+  }
+
   template<typename T>
   template <typename Base_T>
   inline Data_Type<T> Data_Type<T>::bind(const Module& klass)

rice/detail/InstanceRegistry.hpp

@@ -14,6 +14,7 @@ namespace Rice::detail
 
     template <typename T>
     VALUE lookup(T* cppInstance);
+    VALUE lookup(void* cppInstance);
 
     void add(void* cppInstance, VALUE rubyInstance);
     void remove(void* cppInstance);
@@ -23,7 +24,6 @@ namespace Rice::detail
     bool isEnabled = false;
 
   private:
-    VALUE lookup(void* cppInstance);
     std::map<void*, VALUE> objectMap_;
   };
 } // namespace Rice::detail

rice/detail/TypeRegistry.ipp

@@ -13,6 +13,22 @@ namespace Rice::detail
     registry_[key] = std::pair(klass, rbType);
   }
 
+  /* Special case void. Rice defines classes using the class name not a pointer to the
+     class. Thus define_class<void> is more consistent with Rice then 
+     define_class<void*>. However, the types of void and void* are different so we need
+     this special case.
+
+     It is possible to support define_class<void*>, but it requires changing the static
+     assertions on Data_Type and Data_Object and thus seems less desirable (and less 
+     consistent as mentioned above).*/
+  template <>
+  inline void TypeRegistry::add<void>(VALUE klass, rb_data_type_t* rbType)
+  {
+    // The special case, use void*
+    std::type_index key(typeid(void*));
+    registry_[key] = std::pair(klass, rbType);
+  }
+
   template <typename T>
   inline void TypeRegistry::remove()
   {

test/test_Data_Type.cpp

@@ -450,6 +450,93 @@ TESTCASE(null_ptrs)
   ASSERT_EQUAL(Qnil, result.value());
 }
 
+namespace
+{
+  class Helper
+  {
+  public:
+
+    Helper(int value) : value_(value)
+    {
+    }
+
+    int value()
+    {
+      return this->value_;
+    }
+
+  private:
+    int value_;
+  };
+
+  class MyClass2
+  {
+  public:
+    Helper* passThrough(Helper* helper)
+    {
+      return helper;
+    }
+
+    Helper* passThrough(void* helper)
+    {
+      return static_cast<Helper*>(helper);
+    }
+
+    void* returnVoidHelper()
+    {
+      if (!this->helper_)
+        this->helper_ = new Helper(4);
+
+      return static_cast<void*>(this->helper_);
+    }
+
+    bool checkVoidHelper(void* helper)
+    {
+      return helper == this->helper_;
+    }
+
+  private:
+    Helper* helper_ = nullptr;
+  };
+} // namespace
+
+TESTCASE(pointers)
+{
+  Class voidClass = define_class<void>("Void");
+
+  Class helperClass = define_class<Helper>("Helper")
+    .define_constructor(Constructor<Helper, int>())
+    .define_method("value", &Helper::value);
+
+  Class myClass = define_class<MyClass2>("MyClass2")
+    .define_constructor(Constructor<MyClass2>())
+    .define_method<Helper*(MyClass2::*)(Helper*)>("pass_through", &MyClass2::passThrough)
+    .define_method<Helper*(MyClass2::*)(void*)>("pass_through_void", &MyClass2::passThrough)
+    .define_method<void*(MyClass2::*)()>("return_void_helper", &MyClass2::returnVoidHelper)
+    .define_method<bool(MyClass2::*)(void*)>("check_void_helper", &MyClass2::checkVoidHelper);
+
+  Object helper = helperClass.call("new", 5);
+  Object object = myClass.call("new");
+
+  Object result = object.call("pass_through", nullptr);
+  ASSERT_EQUAL(Qnil, result.value());
+
+  result = object.call("pass_through", helper);
+  Object value = result.call("value");
+  ASSERT_EQUAL(5, detail::From_Ruby<int>().convert(value));
+
+  result = object.call("pass_through_void", nullptr);
+  ASSERT_EQUAL(Qnil, result.value());
+
+  result = object.call("pass_through_void", helper);
+  value = result.call("value");
+  ASSERT_EQUAL(5, detail::From_Ruby<int>().convert(value));
+
+   helper = object.call("return_void_helper");
+   result = object.call("check_void_helper", helper);
+   ASSERT_EQUAL(Qtrue, result.value());
+}
+
 namespace
 {
   class SomeClass