[gstreamermm] Gst::BaseTransform: fix vfunc methods

[Marcin Kolny <mkolny src gnome org>]

commit 44b8d279ab1ac0d5f79cc30cb52d5b51a3b8bf76
Author: Marcin Kolny <marcin kolny gmail com>
Date:   Sun Aug 28 08:22:19 2016 +0200

    Gst::BaseTransform: fix vfunc methods

 gstreamer/src/basetransform.ccg |  120 ++++++++++++++++++++++++++++++++++++++-
 gstreamer/src/basetransform.hg  |    9 ++-
 2 files changed, 125 insertions(+), 4 deletions(-)
---
diff --git a/gstreamer/src/basetransform.ccg b/gstreamer/src/basetransform.ccg
index 1cd6a8a..570e4a4 100644
--- a/gstreamer/src/basetransform.ccg
+++ b/gstreamer/src/basetransform.ccg
@@ -214,7 +214,7 @@ FlowReturn Gst::BaseTransform::generate_output_vfunc(Glib::RefPtr<Gst::Buffer>&
 
   if(base && base->generate_output)
   {
-    GstBuffer* gst_buffer;
+    GstBuffer* gst_buffer = nullptr;
     const Gst::FlowReturn result =
       static_cast<Gst::FlowReturn>((*base->generate_output)(gobj(), &gst_buffer));
     outbuf = Glib::wrap(gst_buffer, false); // Don't take copy because callback returns a newly created copy.
@@ -287,5 +287,123 @@ bool Gst::BaseTransform::base_transform_query_vfunc(Gst::PadDirection direction,
   return RType();
 }
 
+bool BaseTransform::propose_allocation_vfunc(const Glib::RefPtr<Gst::Query>& decide_query, const 
Glib::RefPtr<Gst::Query>& query)
+{
+  const auto base = static_cast<BaseClassType*>(
+      g_type_class_peek_parent(G_OBJECT_GET_CLASS(gobject_)) // Get the parent class of the object class 
(The original underlying C class).
+  );
+
+  if(base && base->propose_allocation)
+  {
+    bool retval((*base->propose_allocation)(gobj(),Glib::unwrap(decide_query),Glib::unwrap(query)));
+    return retval;
+  }
+
+  typedef bool RType;
+  return RType();
+}
+
+gboolean BaseTransform_Class::propose_allocation_vfunc_callback(GstBaseTransform* self, GstQuery* 
decide_query, GstQuery* query)
+{
+  const auto obj_base = static_cast<Glib::ObjectBase*>(
+      Glib::ObjectBase::_get_current_wrapper((GObject*)self));
+
+  // Non-gtkmmproc-generated custom classes implicitly call the default
+  // Glib::ObjectBase constructor, which sets is_derived_. But gtkmmproc-
+  // generated classes can use this optimisation, which avoids the unnecessary
+  // parameter conversions if there is no possibility of the virtual function
+  // being overridden:
+  if(obj_base && obj_base->is_derived_())
+  {
+    const auto obj = dynamic_cast<CppObjectType* const>(obj_base);
+    if(obj) // This can be NULL during destruction.
+    {
+      try // Trap C++ exceptions which would normally be lost because this is a C callback.
+      {
+        // Call the virtual member method, which derived classes might override.
+        auto query_cpp = Glib::wrap(query, false);
+        auto decide_query_cpp = Glib::wrap(decide_query, false);
+        auto ret = static_cast<int>(obj->propose_allocation_vfunc(decide_query_cpp, query_cpp));
+        query_cpp.release();
+        decide_query_cpp.release();
+        return ret;
+      }
+      catch(...)
+      {
+        Glib::exception_handlers_invoke();
+      }
+    }
+  }
+
+  BaseClassType *const base = static_cast<BaseClassType*>(
+      g_type_class_peek_parent(G_OBJECT_GET_CLASS(self)) // Get the parent class of the object class (The 
original underlying C class).
+  );
+
+  // Call the original underlying C function:
+  if(base && base->propose_allocation)
+    return (*base->propose_allocation)(self, decide_query, query);
+
+  typedef gboolean RType;
+  return RType();
+}
+
+bool Gst::BaseTransform::decide_allocation_vfunc(const Glib::RefPtr<Gst::Query>& query)
+{
+  const auto base = static_cast<BaseClassType*>(
+      g_type_class_peek_parent(G_OBJECT_GET_CLASS(gobject_)) // Get the parent class of the object class 
(The original underlying C class).
+  );
+
+  if(base && base->decide_allocation)
+  {
+    bool retval((*base->decide_allocation)(gobj(),Glib::unwrap(query)));
+    return retval;
+  }
+
+  typedef bool RType;
+  return RType();
+}
+
+gboolean BaseTransform_Class::decide_allocation_vfunc_callback(GstBaseTransform* self, GstQuery* query)
+{
+  const auto obj_base = static_cast<Glib::ObjectBase*>(
+      Glib::ObjectBase::_get_current_wrapper((GObject*)self));
+
+  // Non-gtkmmproc-generated custom classes implicitly call the default
+  // Glib::ObjectBase constructor, which sets is_derived_. But gtkmmproc-
+  // generated classes can use this optimisation, which avoids the unnecessary
+  // parameter conversions if there is no possibility of the virtual function
+  // being overridden:
+  if(obj_base && obj_base->is_derived_())
+  {
+    const auto obj = dynamic_cast<CppObjectType* const>(obj_base);
+    if(obj) // This can be NULL during destruction.
+    {
+      try // Trap C++ exceptions which would normally be lost because this is a C callback.
+      {
+        // Call the virtual member method, which derived classes might override.
+          auto query_cpp = Glib::wrap(query, false);
+          auto ret = static_cast<int>(obj->decide_allocation_vfunc(query_cpp));
+          query_cpp.release();
+          return ret;
+      }
+      catch(...)
+      {
+        Glib::exception_handlers_invoke();
+      }
+    }
+  }
+
+  BaseClassType *const base = static_cast<BaseClassType*>(
+      g_type_class_peek_parent(G_OBJECT_GET_CLASS(self)) // Get the parent class of the object class (The 
original underlying C class).
+  );
+
+  // Call the original underlying C function:
+  if(base && base->decide_allocation)
+    return (*base->decide_allocation)(self, query);
+
+  typedef gboolean RType;
+  return RType();
+}
+
 
 } //namespace Gst
diff --git a/gstreamer/src/basetransform.hg b/gstreamer/src/basetransform.hg
index aa694dc..f845414 100644
--- a/gstreamer/src/basetransform.hg
+++ b/gstreamer/src/basetransform.hg
@@ -267,7 +267,7 @@ public:
    * implementation, it will be called for all metadata API in the downstream query,
    * otherwise the metadata API is removed.
    */
-  _WRAP_VFUNC(bool decide_allocation(const Glib::RefPtr<Gst::Query>& query), "decide_allocation")
+  virtual bool decide_allocation_vfunc(const Glib::RefPtr<Gst::Query>& query);
 
   /** Return TRUE if the metadata API should be proposed in the upstream allocation query.
    * The default implementation is NULL and will cause all metadata to be removed.
@@ -281,7 +281,7 @@ public:
    * query downstream when in passthrough mode and will copy all the filtered metadata API
    * in non-passthrough mode.
    */
-  _WRAP_VFUNC(bool propose_allocation(const Glib::RefPtr<Gst::Query>& decide_query, const 
Glib::RefPtr<Gst::Query>& query), "propose_allocation")
+  virtual bool propose_allocation_vfunc(const Glib::RefPtr<Gst::Query>& decide_query, const 
Glib::RefPtr<Gst::Query>& query);
 
   #m4 _CONVERSION(`GstBuffer*', `const Glib::RefPtr<Gst::Buffer>&', `Glib::wrap($3, true)')
 
@@ -322,13 +322,16 @@ protected:
   klass->prepare_output_buffer = &prepare_output_buffer_vfunc_callback;
   klass->transform = &transform_vfunc_callback;
   klass->generate_output = &generate_output_vfunc_callback;
-  klass->generate_output = &generate_output_vfunc_callback;
   klass->query = &query_vfunc_callback;
+  klass->propose_allocation = &propose_allocation_vfunc_callback;
+  klass->decide_allocation = &decide_allocation_vfunc_callback;
   _SECTION(SECTION_PH_VFUNCS)
   static GstFlowReturn prepare_output_buffer_vfunc_callback(GstBaseTransform* self, GstBuffer* input, 
GstBuffer** buf);
   static GstFlowReturn transform_vfunc_callback(GstBaseTransform* self, GstBuffer* inbuf, GstBuffer* outbuf);
   static GstFlowReturn generate_output_vfunc_callback(GstBaseTransform* self, GstBuffer** outbuf);
   static gboolean query_vfunc_callback(GstBaseTransform* self, GstPadDirection direction, GstQuery* query);
+  static gboolean propose_allocation_vfunc_callback(GstBaseTransform* self, GstQuery* decide_query, 
GstQuery* query);
+  static gboolean decide_allocation_vfunc_callback(GstBaseTransform* self, GstQuery* query);
   _POP()
 #m4end
 };