Add expression accessor for RPNIterExpr

python_if.c

@@ -40,6 +40,8 @@ and the stack state."},
 };
 
 PyMemberDef RPNIterExpr_members[] = {
+	{"expressions", T_OBJECT, offsetof(PyRPNIterExpr_t, expr), READONLY,
+		"The tuple of expressions"},
 	{NULL}
 };
 
@@ -279,6 +281,19 @@ with given arguments");
 	// Creating rif with a new memory map
 	expr_self->rif = rpn_if_new(rif_params, NULL);
 
+	// Creating the tuple holding RPNExpr instances of expressions
+	expr_self->expr = PyTuple_New(expr_self->rif->params->rpn_sz);
+	for(size_t i=0; i<expr_self->rif->params->rpn_sz;i++)
+	{
+		rpn_expr_t *expr = &expr_self->rif->rpn[i];
+		PyObject *instance = rpnexpr_init_borrowing(expr);
+		if(!instance)
+		{
+			return -1;
+		}
+		PyTuple_SET_ITEM(expr_self->expr, i, instance);
+	}
+
 	return 0;
 }
 

python_if.h

@@ -75,6 +75,9 @@ typedef struct
 	/**@brief Pointer on @ref rpn_if_s */
 	rpn_if_t *rif;
 
+	/**@brief Python tuple with instances of RPNExpr */
+	PyObject *expr;
+
 } PyRPNIterExpr_t;
 
 /**@brief RpnIterExpr __new__ method
@@ -100,12 +103,17 @@ int rpnif_init(PyObject *self, PyObject *args, PyObject *kwds);
  */
 void rpnif_del(PyObject *self);
 
-
+/**@brief Buffer protocol request handler method */
 int rpnif_getbuffer(PyObject *self, Py_buffer *view, int flags);
+/**@brief Buffer protocol request release method */
 void rpnif_releasebuffer(PyObject *self, Py_buffer *view);
 
+/**@brief Return a named tuple of custom rif data */
 PyObject *rpnif_get_params(PyObject *self);
 
+/**@brief Return the list of expressions */
+PyObject *rpnif_get_expr(PyObject *self);
+
 /**@brief RPNIterExpr __getstate__ method for pickling
  * @param cls RPNIterExpr type object
  * @param noargs Not an argument...

python_rpnexpr.c

@@ -93,6 +93,7 @@ PyObject* rpnexpr_new(PyTypeObject *subtype, PyObject *args, PyObject* kwds)
 	expr = (PyRPNExpr_t*)ret;
 	expr->rpn = NULL;
 	expr->args = NULL;
+	expr->borrowed_expr = 0;
 	return ret;
 }
 
@@ -115,13 +116,6 @@ int rpnexpr_init(PyObject *self, PyObject *args, PyObject *kwds)
 		return -1;
 	}
 
-	if(strlen(expr) == 0)
-	{
-		PyErr_SetString(PyExc_ValueError,
-			"RpnExpr.__init__() expect expression argument to be not empty");
-		return -1;
-	}
-
 	if(args_count < 0 || args_count > 255)
 	{
 		snprintf(err_str, 128,
@@ -176,12 +170,44 @@ int rpnexpr_init(PyObject *self, PyObject *args, PyObject *kwds)
 	return 0;
 }
 
+PyObject* rpnexpr_init_borrowing(rpn_expr_t *borrowed)
+{
+	PyObject *args, *ret;
+	PyRPNExpr_t *instance;
+
+	args  = Py_BuildValue("sLL", "", borrowed->args_count,
+			borrowed->stack_sz);
+	if(!args || PyErr_Occurred())
+	{
+		return NULL;
+	}
+
+	ret = PyObject_CallObject(&RPNExprType, args);
+	if(!ret || PyErr_Occurred())
+	{
+		Py_DECREF(args);
+		return NULL;
+	}
+
+	Py_DECREF(args);
+
+	instance = (PyRPNExpr_t*)ret;
+
+	rpn_expr_close(instance->rpn);
+	free(instance->rpn);
+
+	instance->borrowed_expr = 1;
+	instance->rpn = borrowed;
+	
+	return ret;
+}
+
 void rpnexpr_del(PyObject *self)
 {
 	PyRPNExpr_t *expr_self;
 
 	expr_self = (PyRPNExpr_t*)self;
-	if(expr_self->rpn)
+	if(expr_self->rpn && !expr_self->borrowed_expr)
 	{
 		rpn_expr_close(expr_self->rpn);
 		free(expr_self->rpn);
@@ -506,7 +532,6 @@ PyObject* rpnexpr_eval(PyObject* self, PyObject** argv, Py_ssize_t argc)
 	}
 
 	res = rpn_expr_eval(expr_self->rpn, expr_self->args);
-//dprintf(2, "[RES=%lu]\n", res);
 
 	return PyLong_FromUnsignedLong(res);
 }

python_rpnexpr.h

@@ -63,6 +63,10 @@ typedef struct
 	/**@brief Array storing expression argument
 	 * @note As attribute of rpn_expr allowing malloc & free only once */
 	rpn_value_t *args;
+
+	/**@brief If true, someone else will take care of freeing the
+	 * rpn expression at deletion */
+	short borrowed_expr;
 } PyRPNExpr_t;
 
 /**@brief Organize PyRPNExpr_t state data
@@ -76,6 +80,12 @@ typedef struct
 	size_t token_sz;
 } PyRPNExpr_state_t;
 
+/**@brief Return a new instance of RPNExpr with a borrowed expression
+ * @note Borrowed expression means that the rpn_expr_t is handled by someone
+ *       else and should not be freed when the instance is deleted
+ */
+PyObject* rpnexpr_init_borrowing(rpn_expr_t *borrowed);
+
 /**@brief RpnExpr __new__ method
  * @param subtype Type of object being created (pyrpn.RPNExpr)
  * @param args positional arguments for subtype