From 90647f30f856040c218b3605791c2bd96636ca0c Mon Sep 17 00:00:00 2001
From: Dave Abrahams <dave@boostpro.com>
Date: Sat, 2 Feb 2002 20:54:06 +0000
Subject: [PATCH] Initial pointer adoption tests Have instances actually
 dispose of their held C++ objects!

[SVN r12653]
---
 include/boost/python/class.hpp                |  7 +-
 include/boost/python/class_fwd.hpp            | 30 ++++++
 include/boost/python/detail/cv_category.hpp   | 34 +++++++
 include/boost/python/detail/type_list.hpp     | 16 ++++
 include/boost/python/detail/unwind_type.hpp   | 51 ++++++++++
 include/boost/python/manage_new_object.hpp    | 42 +++++++++
 include/boost/python/module.hpp               |  3 +-
 include/boost/python/object/class_object.hpp  | 26 ++++++
 include/boost/python/object/class_wrapper.hpp |  8 +-
 include/boost/python/to_python_owner.hpp      | 93 +++++++++++++++++++
 10 files changed, 300 insertions(+), 10 deletions(-)
 create mode 100644 include/boost/python/class_fwd.hpp
 create mode 100644 include/boost/python/detail/cv_category.hpp
 create mode 100644 include/boost/python/detail/type_list.hpp
 create mode 100644 include/boost/python/detail/unwind_type.hpp
 create mode 100644 include/boost/python/manage_new_object.hpp
 create mode 100644 include/boost/python/object/class_object.hpp
 create mode 100644 include/boost/python/to_python_owner.hpp

diff --git a/include/boost/python/class.hpp b/include/boost/python/class.hpp
index 0f8d2a69..b63236c8 100644
--- a/include/boost/python/class.hpp
+++ b/include/boost/python/class.hpp
@@ -6,6 +6,7 @@
 #ifndef CLASS_DWA200216_HPP
 # define CLASS_DWA200216_HPP
 
+# include <boost/python/class_fwd.hpp>
 # include <boost/python/reference.hpp>
 # include <boost/python/object/class.hpp>
 # include <boost/python/converter/type_id.hpp>
@@ -14,7 +15,7 @@
 # include <boost/python/object/class_converters.hpp>
 # include <boost/mpl/size.hpp>
 # include <boost/mpl/for_each.hpp>
-# include <boost/mpl/type_list.hpp>
+# include <boost/python/detail/type_list.hpp>
 
 namespace // put some convenience classes into the unnamed namespace for the user
 {
@@ -80,8 +81,8 @@ namespace detail
 //
 template <
     class T // class being wrapped
-    , class Bases = mpl::type_list<>::type
-    , class HolderGenerator = objects::value_holder_generator
+    , class Bases
+    , class HolderGenerator
     >
 class class_ : private objects::class_base
 {
diff --git a/include/boost/python/class_fwd.hpp b/include/boost/python/class_fwd.hpp
new file mode 100644
index 00000000..6faf7aae
--- /dev/null
+++ b/include/boost/python/class_fwd.hpp
@@ -0,0 +1,30 @@
+// Copyright David Abrahams 2002. Permission to copy, use,
+// modify, sell and distribute this software is granted provided this
+// copyright notice appears in all copies. This software is provided
+// "as is" without express or implied warranty, and with no claim as
+// to its suitability for any purpose.
+#ifndef CLASS_FWD_DWA200222_HPP
+# define CLASS_FWD_DWA200222_HPP
+
+namespace boost { namespace python { 
+
+namespace detail
+{
+  struct empty_list;
+}
+
+namespace objects
+{
+  struct value_holder_generator;
+}
+
+template <
+    class T // class being wrapped
+    , class Bases = detail::empty_list
+    , class HolderGenerator = objects::value_holder_generator
+    >
+class class_;
+
+}} // namespace boost::python
+
+#endif // CLASS_FWD_DWA200222_HPP
diff --git a/include/boost/python/detail/cv_category.hpp b/include/boost/python/detail/cv_category.hpp
new file mode 100644
index 00000000..f4ac4b92
--- /dev/null
+++ b/include/boost/python/detail/cv_category.hpp
@@ -0,0 +1,34 @@
+// Copyright David Abrahams 2002. Permission to copy, use,
+// modify, sell and distribute this software is granted provided this
+// copyright notice appears in all copies. This software is provided
+// "as is" without express or implied warranty, and with no claim as
+// to its suitability for any purpose.
+#ifndef CV_CATEGORY_DWA200222_HPP
+# define CV_CATEGORY_DWA200222_HPP
+# include <boost/type_traits/cv_traits.hpp>
+
+namespace boost { namespace python { namespace detail { 
+
+template <bool is_const_, bool is_volatile_>
+struct cv_tag
+{
+    BOOST_STATIC_CONSTANT(bool, is_const = is_const_);
+    BOOST_STATIC_CONSTANT(bool, is_volatile = is_const_);
+};
+
+typedef cv_tag<false,false> cv_unqualified;
+typedef cv_tag<true,false> const_;
+typedef cv_tag<false,true> volatile_;
+typedef cv_tag<true,true> const_volatile_;
+
+template <class T>
+struct cv_category
+{
+    BOOST_STATIC_CONSTANT(bool, c = is_const<T>::value);
+    BOOST_STATIC_CONSTANT(bool, v = is_volatile<T>::value);
+    typedef cv_tag<c,v> type;
+};
+
+}}} // namespace boost::python::detail
+
+#endif // CV_CATEGORY_DWA200222_HPP
diff --git a/include/boost/python/detail/type_list.hpp b/include/boost/python/detail/type_list.hpp
new file mode 100644
index 00000000..66ac3857
--- /dev/null
+++ b/include/boost/python/detail/type_list.hpp
@@ -0,0 +1,16 @@
+// Copyright David Abrahams 2002. Permission to copy, use,
+// modify, sell and distribute this software is granted provided this
+// copyright notice appears in all copies. This software is provided
+// "as is" without express or implied warranty, and with no claim as
+// to its suitability for any purpose.
+#ifndef TYPE_LIST_DWA200222_HPP
+# define TYPE_LIST_DWA200222_HPP
+# include <boost/mpl/type_list.hpp>
+
+namespace boost { namespace python { namespace detail { 
+
+struct empty_list : boost::mpl::type_list<>::type {};
+
+}}} // namespace boost::python::detail
+
+#endif // TYPE_LIST_DWA200222_HPP
diff --git a/include/boost/python/detail/unwind_type.hpp b/include/boost/python/detail/unwind_type.hpp
new file mode 100644
index 00000000..eb103be4
--- /dev/null
+++ b/include/boost/python/detail/unwind_type.hpp
@@ -0,0 +1,51 @@
+// Copyright David Abrahams 2002. Permission to copy, use,
+// modify, sell and distribute this software is granted provided this
+// copyright notice appears in all copies. This software is provided
+// "as is" without express or implied warranty, and with no claim as
+// to its suitability for any purpose.
+#ifndef UNWIND_TYPE_DWA200222_HPP
+# define UNWIND_TYPE_DWA200222_HPP
+
+# include <boost/python/detail/cv_category.hpp>
+
+namespace boost { namespace python { namespace detail { 
+
+template <class Generator, class U>
+inline typename Generator::result_type
+unwind_type_cv(U* p, cv_unqualified, Generator* = 0)
+{
+    return Generator::execute(p);
+}
+    
+template <class Generator, class U>
+inline typename Generator::result_type
+unwind_type_cv(U const* p, const_, Generator* = 0)
+{
+    return unwind_type(const_cast<U*>(p), (Generator*)0);
+}
+    
+template <class Generator, class U>
+inline typename Generator::result_type
+unwind_type_cv(U volatile* p, volatile_, Generator* = 0)
+{
+    return unwind_type(const_cast<U*>(p), (Generator*)0);
+}
+    
+template <class Generator, class U>
+inline typename Generator::result_type
+unwind_type_cv(U const volatile* p, const_volatile_, Generator* = 0)
+{
+    return unwind_type(const_cast<U*>(p), (Generator*)0);
+}
+    
+template <class Generator, class U>
+inline typename Generator::result_type
+unwind_type(U* p, Generator* = 0)
+{
+    typedef typename cv_category<U>::type tag;
+    return unwind_type_cv<Generator>(p, tag());
+}
+
+}}} // namespace boost::python::detail
+
+#endif // UNWIND_TYPE_DWA200222_HPP
diff --git a/include/boost/python/manage_new_object.hpp b/include/boost/python/manage_new_object.hpp
new file mode 100644
index 00000000..1c41a75d
--- /dev/null
+++ b/include/boost/python/manage_new_object.hpp
@@ -0,0 +1,42 @@
+// Copyright David Abrahams 2002. Permission to copy, use,
+// modify, sell and distribute this software is granted provided this
+// copyright notice appears in all copies. This software is provided
+// "as is" without express or implied warranty, and with no claim as
+// to its suitability for any purpose.
+#ifndef MANAGE_NEW_OBJECT_DWA200222_HPP
+# define MANAGE_NEW_OBJECT_DWA200222_HPP
+# include <boost/python/detail/indirect_traits.hpp>
+# include <boost/mpl/select_type.hpp>
+# include <boost/python/to_python_owner.hpp>
+# include <boost/type_traits/composite_traits.hpp>
+
+namespace boost { namespace python { 
+
+namespace detail
+{
+  template <class R>
+  struct manage_new_object_requires_a_pointer_return_type
+# if defined(__GNUC__) && __GNUC__ >= 3 || defined(__EDG__)
+  {}
+# endif
+  ;
+}
+
+template <class T> struct to_python_value;
+
+struct manage_new_object
+{
+    template <class T>
+    struct apply
+    {
+        typedef typename mpl::select_type<
+            boost::is_pointer<T>::value
+            , to_python_owner<T>
+            , detail::manage_new_object_requires_a_pointer_return_type<T>
+        >::type type;
+    };
+};
+
+}} // namespace boost::python
+
+#endif // MANAGE_NEW_OBJECT_DWA200222_HPP
diff --git a/include/boost/python/module.hpp b/include/boost/python/module.hpp
index 3a243b06..1d4fdd6d 100644
--- a/include/boost/python/module.hpp
+++ b/include/boost/python/module.hpp
@@ -12,11 +12,10 @@
 # include <boost/python/make_function.hpp>
 # include <boost/python/objects.hpp>
 # include <boost/python/detail/wrap_python.hpp>
+# include <boost/python/class_fwd.hpp>
 
 namespace boost { namespace python {
 
-template <class T, class Bases, class HolderGenerator> class class_;
-
 class BOOST_PYTHON_DECL module_base
 {
  public:
diff --git a/include/boost/python/object/class_object.hpp b/include/boost/python/object/class_object.hpp
new file mode 100644
index 00000000..76960762
--- /dev/null
+++ b/include/boost/python/object/class_object.hpp
@@ -0,0 +1,26 @@
+// Copyright David Abrahams 2002. Permission to copy, use,
+// modify, sell and distribute this software is granted provided this
+// copyright notice appears in all copies. This software is provided
+// "as is" without express or implied warranty, and with no claim as
+// to its suitability for any purpose.
+#ifndef CLASS_OBJECT_DWA200222_HPP
+# define CLASS_OBJECT_DWA200222_HPP
+
+# include <boost/python/converter/type_id.hpp>
+# include <boost/python/converter/registry.hpp>
+
+namespace boost { namespace python { namespace objects { 
+
+template <class T>
+struct class_object
+{
+    static PyTypeObject*& reference;
+};
+
+template <class T>
+PyTypeObject*& class_object<T>::reference = converter::registry::class_object(
+    converter::undecorated_type_id<T>());
+
+}}} // namespace boost::python::objects
+
+#endif // CLASS_OBJECT_DWA200222_HPP
diff --git a/include/boost/python/object/class_wrapper.hpp b/include/boost/python/object/class_wrapper.hpp
index 4a52f290..f8702205 100644
--- a/include/boost/python/object/class_wrapper.hpp
+++ b/include/boost/python/object/class_wrapper.hpp
@@ -25,9 +25,9 @@ struct class_wrapper
     
     static PyObject* convert(T const& x)
     {
-        // Don't call the type to do the construction, since that
-        // would require the registration of an __init__ copy
-        // constructor. Instead, just construct the object in place.
+        // Don't call the type directly to do the construction, since
+        // that would require the registration of an appropriate
+        // __init__ function.
         PyObject* raw_result = m_class_object->tp_alloc(m_class_object, 0);
 
         if (raw_result == 0)
@@ -37,8 +37,6 @@ struct class_wrapper
         // exceptions.
         ref result(raw_result, ref::allow_null());
 
-        ((instance*)raw_result)->objects = 0;
-        
         // Build a value_holder to contain the object using the copy
         // constructor
         value_holder<T>* p = new value_holder<T>(raw_result, cref(x));
diff --git a/include/boost/python/to_python_owner.hpp b/include/boost/python/to_python_owner.hpp
new file mode 100644
index 00000000..7d3ee5ae
--- /dev/null
+++ b/include/boost/python/to_python_owner.hpp
@@ -0,0 +1,93 @@
+// Copyright David Abrahams 2002. Permission to copy, use,
+// modify, sell and distribute this software is granted provided this
+// copyright notice appears in all copies. This software is provided
+// "as is" without express or implied warranty, and with no claim as
+// to its suitability for any purpose.
+#ifndef TO_PYTHON_OWNER_DWA200221_HPP
+# define TO_PYTHON_OWNER_DWA200221_HPP
+
+# include <boost/type_traits/object_traits.hpp>
+# include <boost/python/object/pointer_holder.hpp>
+# include <boost/python/object/class_object.hpp>
+# include <boost/python/detail/unwind_type.hpp>
+# include <memory>
+
+namespace boost { namespace python {
+
+template <class T>
+struct to_python_owner
+{
+    static bool convertible();
+    PyObject* operator()(T ptr) const;
+ private:
+    static PyTypeObject* type();
+};
+
+//
+// implementations
+//
+namespace detail
+{
+  struct make_owning_holder
+  {
+      typedef objects::instance_holder* result_type;
+      template <class T>
+      static result_type execute(T* p)
+      {
+          return new objects::pointer_holder<std::auto_ptr<T>, T>(
+              std::auto_ptr<T>(p));
+      }
+  };
+
+  struct get_pointer_class
+  {
+      typedef PyTypeObject* result_type;
+      template <class T>
+      static result_type execute(T* p)
+      {
+          BOOST_STATIC_ASSERT(is_class<T>::value);
+          return python::objects::class_object<T>::reference;
+      }
+  };
+}
+
+template <class T>
+inline bool to_python_owner<T>::convertible()
+{
+    BOOST_STATIC_ASSERT(is_pointer<T>::value);
+    return type() != 0;
+}
+
+template <class T>
+inline PyObject* to_python_owner<T>::operator()(T x) const
+{
+    PyObject* raw_result = type()->tp_alloc(type(), 0);
+
+    if (raw_result == 0)
+        return 0;
+
+    // Everything's OK; Bypass NULL checks but guard against
+    // exceptions.
+    ref result(raw_result, ref::allow_null());
+
+    // Build a value_holder to contain the object using the copy
+    // constructor
+    objects::instance_holder* p =
+        detail::unwind_type<detail::make_owning_holder>(x);
+
+    // Install it in the instance
+    p->install(raw_result);
+
+    // Return the new result
+    return result.release();
+}
+
+template <class T>
+inline PyTypeObject* to_python_owner<T>::type()
+{
+    return detail::unwind_type<detail::get_pointer_class>(T(0));
+}
+
+}} // namespace boost::python
+
+#endif // TO_PYTHON_OWNER_DWA200221_HPP