talloc: add _pytalloc_get_ptr/_pytalloc_get_mem_ctx helper functions

This allows us to check which type is involved, and dereference
that type correctly

Pair-Programmed-With: Stefan Metzmacher <metze@samba.org>

Signed-off-by: Andrew Bartlett <abartlet@samba.org>
Signed-off-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Garming Sam <garming@catalyst.net.nz>

lib/talloc/pytalloc.h

@@ -42,8 +42,10 @@ int pytalloc_Check(PyObject *);
  * when talloc_get_type() returns NULL. */
 #define pytalloc_get_type(py_obj, type) (talloc_get_type(pytalloc_get_ptr(py_obj), type))
 
-#define pytalloc_get_ptr(py_obj) (((pytalloc_Object *)py_obj)->ptr)
-#define pytalloc_get_mem_ctx(py_obj)  ((pytalloc_Object *)py_obj)->talloc_ctx
+void *_pytalloc_get_ptr(PyObject *py_obj);
+#define pytalloc_get_ptr(py_obj) _pytalloc_get_ptr((PyObject *)(py_obj))
+TALLOC_CTX *_pytalloc_get_mem_ctx(PyObject *py_obj);
+#define pytalloc_get_mem_ctx(py_obj) _pytalloc_get_mem_ctx((PyObject *)(py_obj))
 
 PyObject *pytalloc_steal_ex(PyTypeObject *py_type, TALLOC_CTX *mem_ctx, void *ptr);
 PyObject *pytalloc_steal(PyTypeObject *py_type, void *ptr);

lib/talloc/pytalloc_util.c

@@ -120,3 +120,13 @@ _PUBLIC_ int pytalloc_Check(PyObject *obj)
 
 	return PyObject_TypeCheck(obj, tp);
 }
+
+_PUBLIC_ void *_pytalloc_get_ptr(PyObject *py_obj)
+{
+	return ((pytalloc_Object *)py_obj)->ptr;
+}
+
+_PUBLIC_ TALLOC_CTX *_pytalloc_get_mem_ctx(PyObject *py_obj)
+{
+	return ((pytalloc_Object *)py_obj)->talloc_ctx;
+}

lib/talloc/test_pytalloc.c

@@ -43,13 +43,13 @@ static PyObject *testpytalloc_get_object_type(PyObject *mod) {
 }
 
 static PyObject *testpytalloc_reference(PyObject *mod, PyObject *args) {
-	pytalloc_Object *source = NULL;
+	PyObject *source = NULL;
 	void *ptr;
 
 	if (!PyArg_ParseTuple(args, "O!", pytalloc_GetObjectType(), &source))
 		return NULL;
 
-	ptr = source->ptr;
+	ptr = pytalloc_get_ptr(source);
 	return pytalloc_reference_ex(pytalloc_GetObjectType(), ptr, ptr);
 }
 

lib/talloc/wscript

@@ -133,7 +133,7 @@ def build(bld):
                 vnum=VERSION,
                 hide_symbols=True,
                 abi_directory='ABI',
-                abi_match='pytalloc_*',
+                abi_match='pytalloc_* _pytalloc_*',
                 private_library=private_library,
                 public_headers=('' if private_library else 'pytalloc.h'),
                 pc_files='pytalloc-util.pc'