On Tue, 2009-11-17 at 19:45 -0500, Terry Reedy wrote:
> A.M. Kuchling wrote:
> > On Mon, Nov 16, 2009 at 03:27:53PM -0500, David Malcolm wrote:
> >> Has anyone else looked at using Coccinelle/spatch[1] on CPython source
> >> code?
> >
> > For an excellent explanation of Coccinelle, see
> > <http://lwn.net/Articles/315686/>.
>
> For those who have not looked, Coccinelle means ladybug (a bug-eating
> bug ;-) in French. Its principle use to to take C code and a SmPl file
> of high-level patch descriptions (fixers, in 2to3 talk) and produce a
> standard diff file. I wonder if this could be used to help people
> migrate C extensions to 3.1, by developing a SmPl file with the needed
> changes dictated by API changes. This is similar to its motivating
> application to Linux. From
>
> http://coccinelle.lip6.fr/
>
> "Coccinelle is a program matching and transformation engine which
> provides the language SmPL (Semantic Patch Language) for specifying
> desired matches and transformations in C code. Coccinelle was initially
> targeted towards performing collateral evolutions in Linux. Such
> evolutions comprise the changes that are needed in client code in
> response to evolutions in library APIs, and may include modifications
> such as renaming a function, adding a function argument whose value is
> somehow context-dependent, and reorganizing a data structure. "
>
> As I understand it, the problem with C extensions and 3.1 is the current
> lack of a "collateral evolution" tool like 2to3 for Python code.
Indeed; I think it may be possible to use Coccinelle for this.
Here's a .cocci semantic patch to convert non-PyObject* dereferences of
an "ob_type" field to use Py_TYPE macro instead.
@@
PyObject *py_obj_ptr;
type T;
T non_py_obj_ptr;
@@
(
py_obj_ptr->ob_type
|
- non_py_obj_ptr->ob_type
+ Py_TYPE(non_py_obj_ptr)
)
I was able to use this to generate the attached patch for the DBus
python bindings. Note that it leaves dereferences of a PyObject*
untouched, and works inside sub-expressions. (There's some noise at the
typedef of Server; I don't know why).
Hope this is helpful
Dave
diff --git a/_dbus_bindings/conn.c b/_dbus_bindings/conn.c
index c30f167..157218d 100644
--- a/_dbus_bindings/conn.c
+++ b/_dbus_bindings/conn.c
@@ -389,7 +389,7 @@ static void Connection_tp_dealloc(Connection *self)
DBG("Connection at %p: freeing self", self);
PyErr_Restore(et, ev, etb);
- (self->ob_type->tp_free)((PyObject *)self);
+ (Py_TYPE(self)->tp_free)((PyObject *)self);
}
/* Connection type object =========================================== */
diff --git a/_dbus_bindings/libdbusconn.c b/_dbus_bindings/libdbusconn.c
index 9bd8def..c33bb7c 100644
--- a/_dbus_bindings/libdbusconn.c
+++ b/_dbus_bindings/libdbusconn.c
@@ -73,7 +73,7 @@ DBusPyLibDBusConnection_tp_dealloc(Connection *self)
}
PyErr_Restore(et, ev, etb);
- (self->ob_type->tp_free)((PyObject *) self);
+ (Py_TYPE(self)->tp_free)((PyObject *) self);
}
PyTypeObject DBusPyLibDBusConnection_Type = {
diff --git a/_dbus_bindings/message.c b/_dbus_bindings/message.c
index a2c04c3..ee0cbd6 100644
--- a/_dbus_bindings/message.c
+++ b/_dbus_bindings/message.c
@@ -53,7 +53,7 @@ static void Message_tp_dealloc(Message *self)
if (self->msg) {
dbus_message_unref(self->msg);
}
- self->ob_type->tp_free((PyObject *)self);
+ Py_TYPE(self)->tp_free((PyObject *)self);
}
static PyObject *
diff --git a/_dbus_bindings/server.c b/_dbus_bindings/server.c
index 7fc4f70..ba39f74 100644
--- a/_dbus_bindings/server.c
+++ b/_dbus_bindings/server.c
@@ -40,7 +40,7 @@ typedef struct {
PyObject *weaklist;
PyObject *mainloop;
-} Server;
+}Server;
PyDoc_STRVAR(Server_tp_doc,
"A D-Bus server.\n"
@@ -429,7 +429,7 @@ static void Server_tp_dealloc(Server *self)
DBG("Server at %p: freeing self", self);
PyErr_Restore(et, ev, etb);
- (self->ob_type->tp_free)((PyObject *)self);
+ (Py_TYPE(self)->tp_free)((PyObject *)self);
}
PyDoc_STRVAR(Server_disconnect__doc__,
_______________________________________________
Python-Dev mailing list
Python-Dev@python.org
http://mail.python.org/mailman/listinfo/python-dev
Unsubscribe:
http://mail.python.org/mailman/options/python-dev/archive%40mail-archive.com
