gras: revisit container storage after yesterdays learning

The mechanisms of connect are now resonsible for grabbing the container ref.
When the object is a shared ptr, the element contructor overload sets weakself.
When the object is in python, the python reference is held,
even if its shared ptr underneath that.

* removed the need for shared_from_this
* removed the ref stuff in python Block

3 files changed, 56 insertions, 46 deletions

diff --git a/python/gras/GRAS_Block.i b/python/gras/GRAS_Block.i
index 9cd96e2..f429e30 100644
--- a/python/gras/GRAS_Block.i
+++ b/python/gras/GRAS_Block.i
@@ -56,7 +56,6 @@
 %{
 #include <gras/block.hpp>
 #include <iostream>
-#include <boost/make_shared.hpp>
 %}
 
 %include <gras/element.i>
@@ -65,42 +64,6 @@
 %include "GRAS_Utils.i"
 
 ////////////////////////////////////////////////////////////////////////
-// Create a reference holder for python objects
-////////////////////////////////////////////////////////////////////////
-%inline %{
-
-struct PyObjectRefHolder
-{
-    PyObjectRefHolder(PyObject *o):
-        o(o)
-    {
-        Py_INCREF(o);
-    }
-    ~PyObjectRefHolder(void)
-    {
-        PyGILPhondler phil;
-        Py_DECREF(o);
-    }
-    PyObject *o;
-};
-
-struct WeakElementPyObject : gras::WeakElement
-{
-    WeakElementPyObject(PyObject *o):
-        o(o)
-    {
-        //NOP
-    }
-    boost::shared_ptr<void> lock(void)
-    {
-        return boost::make_shared<PyObjectRefHolder>(o);
-    }
-    PyObject *o;
-};
-
-%}
-
-////////////////////////////////////////////////////////////////////////
 // Make a special block with safe overloads
 ////////////////////////////////////////////////////////////////////////
 %inline %{
@@ -122,11 +85,6 @@ struct BlockPython : Block
         this->reset();
     }
 
-    void _Py_init_weak_ref__(PyObject *o)
-    {
-        this->weak_self.reset(new WeakElementPyObject(o));
-    }
-
     void notify_active(void)
     {
         PyGILPhondler phil;
@@ -241,7 +199,6 @@ def sig_to_dtype_sig(sig):
 class Block(BlockPython):
     def __init__(self, name='Block', in_sig=None, out_sig=None):
         BlockPython.__init__(self, name)
-        self._Py_init_weak_ref__(self)
         self.set_input_signature(in_sig)
         self.set_output_signature(out_sig)
         self.__prop_registry = dict()
diff --git a/python/gras/GRAS_HierBlock.i b/python/gras/GRAS_HierBlock.i
index 4afe8fe..2ffb349 100644
--- a/python/gras/GRAS_HierBlock.i
+++ b/python/gras/GRAS_HierBlock.i
@@ -20,6 +20,7 @@
 %{
 #include <gras/hier_block.hpp>
 #include <gras/top_block.hpp>
+#include <boost/make_shared.hpp>
 %}
 
 ////////////////////////////////////////////////////////////////////////
@@ -29,10 +30,37 @@
 %include <gras/hier_block.i>
 %include <gras/top_block.hpp>
 
+%include "GRAS_Utils.i"
+
+////////////////////////////////////////////////////////////////////////
+// weak element overload for python
+////////////////////////////////////////////////////////////////////////
+%inline %{
+
+struct WeakElementPyObject : gras::WeakElement
+{
+    WeakElementPyObject(PyObject *o):
+        o(o)
+    {
+        //NOP
+    }
+    boost::shared_ptr<const void> lock(void)
+    {
+        return boost::make_shared<PyObjectRefHolder>(o);
+    }
+    PyObject *o;
+};
+
+inline void set_weak_py_self(gras::Element &elem, PyObject *o)
+{
+    elem.weak_self.reset(new WeakElementPyObject(o));
+}
+
+%}
+
 ////////////////////////////////////////////////////////////////////////
 // Make a special top block with python safe unlocking wait
 ////////////////////////////////////////////////////////////////////////
-%include "GRAS_Utils.i"
 %inline %{
 
 namespace gras
@@ -109,13 +137,16 @@ struct HierBlockPython : HierBlock
 
 def to_element(obj):
     if isinstance(obj, Element): return obj
-    try: return obj.shared_to_element()
+    try:
+        elem = obj.to_element()
+        set_weak_py_self(elem, obj)
+        return elem
     except: raise Exception('cant coerce obj %s to element'%(obj))
 
 def internal_connect__(fcn, obj, *args):
 
     if len(args) == 1:
-        elem = (args[0])
+        elem = to_element(args[0])
         fcn(obj, elem)
         return
 
diff --git a/python/gras/GRAS_Utils.i b/python/gras/GRAS_Utils.i
index afe3314..1b23aca 100644
--- a/python/gras/GRAS_Utils.i
+++ b/python/gras/GRAS_Utils.i
@@ -41,3 +41,25 @@ struct PyTSPhondler
 };
 
 %}
+
+////////////////////////////////////////////////////////////////////////
+// Create a reference holder for python objects
+////////////////////////////////////////////////////////////////////////
+%inline %{
+
+struct PyObjectRefHolder
+{
+    PyObjectRefHolder(PyObject *o):
+        o(o)
+    {
+        Py_INCREF(o);
+    }
+    ~PyObjectRefHolder(void)
+    {
+        PyGILPhondler phil;
+        Py_DECREF(o);
+    }
+    PyObject *o;
+};
+
+%}