* Use PyVarObject_HEAD_INIT instead of PyObject_HEAD_INIT on type struct header.
* Backport many minor fixes from Python 3 doc to minimize diff.
Moving on, we come to the crunch --- the type object. ::
static PyTypeObject noddy_NoddyType = {
- PyObject_HEAD_INIT(NULL)
- 0, /*ob_size*/
- "noddy.Noddy", /*tp_name*/
- sizeof(noddy_NoddyObject), /*tp_basicsize*/
- 0, /*tp_itemsize*/
- 0, /*tp_dealloc*/
- 0, /*tp_print*/
- 0, /*tp_getattr*/
- 0, /*tp_setattr*/
- 0, /*tp_compare*/
- 0, /*tp_repr*/
- 0, /*tp_as_number*/
- 0, /*tp_as_sequence*/
- 0, /*tp_as_mapping*/
- 0, /*tp_hash */
- 0, /*tp_call*/
- 0, /*tp_str*/
- 0, /*tp_getattro*/
- 0, /*tp_setattro*/
- 0, /*tp_as_buffer*/
- Py_TPFLAGS_DEFAULT, /*tp_flags*/
+ PyVarObject_HEAD_INIT(NULL, 0)
+ "noddy.Noddy", /* tp_name */
+ sizeof(noddy_NoddyObject), /* tp_basicsize */
+ 0, /* tp_itemsize */
+ 0, /* tp_dealloc */
+ 0, /* tp_print */
+ 0, /* tp_getattr */
+ 0, /* tp_setattr */
+ 0, /* tp_compare */
+ 0, /* tp_repr */
+ 0, /* tp_as_number */
+ 0, /* tp_as_sequence */
+ 0, /* tp_as_mapping */
+ 0, /* tp_hash */
+ 0, /* tp_call */
+ 0, /* tp_str */
+ 0, /* tp_getattro */
+ 0, /* tp_setattro */
+ 0, /* tp_as_buffer */
+ Py_TPFLAGS_DEFAULT, /* tp_flags */
"Noddy objects", /* tp_doc */
};
This is so important that we're going to pick the top of it apart still
further::
- PyObject_HEAD_INIT(NULL)
+ PyVarObject_HEAD_INIT(NULL, 0)
This line is a bit of a wart; what we'd like to write is::
- PyObject_HEAD_INIT(&PyType_Type)
+ PyVarObject_HEAD_INIT(&PyType_Type, 0)
as the type of a type object is "type", but this isn't strictly conforming C and
some compilers complain. Fortunately, this member will be filled in for us by
:c:func:`PyType_Ready`. ::
- 0, /* ob_size */
-
-The :attr:`ob_size` field of the header is not used; its presence in the type
-structure is a historical artifact that is maintained for binary compatibility
-with extension modules compiled for older versions of Python. Always set this
-field to zero. ::
-
"noddy.Noddy", /* tp_name */
The name of our type. This will appear in the default textual representation of
Skipping a number of type methods that we don't provide, we set the class flags
to :const:`Py_TPFLAGS_DEFAULT`. ::
- Py_TPFLAGS_DEFAULT, /*tp_flags*/
+ Py_TPFLAGS_DEFAULT, /* tp_flags */
All types should include this constant in their flags. It enables all of the
members defined by the current version of Python.
Adding data and methods to the Basic example
--------------------------------------------
-Let's expend the basic example to add some data and methods. Let's also make
+Let's extend the basic example to add some data and methods. Let's also make
the type usable as a base class. We'll create a new module, :mod:`noddy2` that
adds these capabilities:
{
Py_XDECREF(self->first);
Py_XDECREF(self->last);
- self->ob_type->tp_free((PyObject*)self);
+ Py_TYPE(self)->tp_free((PyObject*)self);
}
which is assigned to the :c:member:`~PyTypeObject.tp_dealloc` member::
The method is implemented as a C function that takes a :class:`Noddy` (or
:class:`Noddy` subclass) instance as the first argument. Methods always take an
instance as the first argument. Methods often take positional and keyword
-arguments as well, but in this cased we don't take any and don't need to accept
+arguments as well, but in this case we don't take any and don't need to accept
a positional argument tuple or keyword argument dictionary. This method is
equivalent to the Python method::
Finally, we add the :const:`Py_TPFLAGS_HAVE_GC` flag to the class flags::
- Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE | Py_TPFLAGS_HAVE_GC, /*tp_flags*/
+ Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE | Py_TPFLAGS_HAVE_GC, /* tp_flags */
That's pretty much it. If we had written custom :c:member:`~PyTypeObject.tp_alloc` or
:c:member:`~PyTypeObject.tp_free` slots, we'd need to modify them for cyclic-garbage collection.
This function is called when the reference count of the instance of your type is
reduced to zero and the Python interpreter wants to reclaim it. If your type
-has memory to free or other clean-up to perform, put it here. The object itself
-needs to be freed here as well. Here is an example of this function::
+has memory to free or other clean-up to perform, you can put it here. The
+object itself needs to be freed here as well. Here is an example of this
+function::
static void
newdatatype_dealloc(newdatatypeobject * obj)
{
free(obj->obj_UnderlyingDatatypePtr);
- obj->ob_type->tp_free(obj);
+ Py_TYPE(obj)->tp_free(obj);
}
.. index::
Py_DECREF(self->my_callback);
}
- obj->ob_type->tp_free((PyObject*)self);
+ Py_TYPE(obj)->tp_free((PyObject*)self);
}
} noddy_NoddyObject;
static PyTypeObject noddy_NoddyType = {
- PyObject_HEAD_INIT(NULL)
- 0, /*ob_size*/
- "noddy.Noddy", /*tp_name*/
- sizeof(noddy_NoddyObject), /*tp_basicsize*/
- 0, /*tp_itemsize*/
- 0, /*tp_dealloc*/
- 0, /*tp_print*/
- 0, /*tp_getattr*/
- 0, /*tp_setattr*/
- 0, /*tp_compare*/
- 0, /*tp_repr*/
- 0, /*tp_as_number*/
- 0, /*tp_as_sequence*/
- 0, /*tp_as_mapping*/
- 0, /*tp_hash */
- 0, /*tp_call*/
- 0, /*tp_str*/
- 0, /*tp_getattro*/
- 0, /*tp_setattro*/
- 0, /*tp_as_buffer*/
- Py_TPFLAGS_DEFAULT, /*tp_flags*/
+ PyVarObject_HEAD_INIT(NULL, 0)
+ "noddy.Noddy", /* tp_name */
+ sizeof(noddy_NoddyObject), /* tp_basicsize */
+ 0, /* tp_itemsize */
+ 0, /* tp_dealloc */
+ 0, /* tp_print */
+ 0, /* tp_getattr */
+ 0, /* tp_setattr */
+ 0, /* tp_compare */
+ 0, /* tp_repr */
+ 0, /* tp_as_number */
+ 0, /* tp_as_sequence */
+ 0, /* tp_as_mapping */
+ 0, /* tp_hash */
+ 0, /* tp_call */
+ 0, /* tp_str */
+ 0, /* tp_getattro */
+ 0, /* tp_setattro */
+ 0, /* tp_as_buffer */
+ Py_TPFLAGS_DEFAULT, /* tp_flags */
"Noddy objects", /* tp_doc */
};
{
Py_XDECREF(self->first);
Py_XDECREF(self->last);
- self->ob_type->tp_free((PyObject*)self);
+ Py_TYPE(self)->tp_free((PyObject*)self);
}
static PyObject *
self = (Noddy *)type->tp_alloc(type, 0);
if (self != NULL) {
self->first = PyString_FromString("");
- if (self->first == NULL)
- {
+ if (self->first == NULL) {
Py_DECREF(self);
return NULL;
- }
-
+ }
+
self->last = PyString_FromString("");
- if (self->last == NULL)
- {
+ if (self->last == NULL) {
Py_DECREF(self);
return NULL;
- }
+ }
self->number = 0;
}
static char *kwlist[] = {"first", "last", "number", NULL};
- if (! PyArg_ParseTupleAndKeywords(args, kwds, "|OOi", kwlist,
- &first, &last,
+ if (! PyArg_ParseTupleAndKeywords(args, kwds, "|OOi", kwlist,
+ &first, &last,
&self->number))
- return -1;
+ return -1;
if (first) {
tmp = self->first;
result = PyString_Format(format, args);
Py_DECREF(args);
-
+
return result;
}
};
static PyTypeObject NoddyType = {
- PyObject_HEAD_INIT(NULL)
- 0, /*ob_size*/
- "noddy.Noddy", /*tp_name*/
- sizeof(Noddy), /*tp_basicsize*/
- 0, /*tp_itemsize*/
- (destructor)Noddy_dealloc, /*tp_dealloc*/
- 0, /*tp_print*/
- 0, /*tp_getattr*/
- 0, /*tp_setattr*/
- 0, /*tp_compare*/
- 0, /*tp_repr*/
- 0, /*tp_as_number*/
- 0, /*tp_as_sequence*/
- 0, /*tp_as_mapping*/
- 0, /*tp_hash */
- 0, /*tp_call*/
- 0, /*tp_str*/
- 0, /*tp_getattro*/
- 0, /*tp_setattro*/
- 0, /*tp_as_buffer*/
- Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, /*tp_flags*/
+ PyVarObject_HEAD_INIT(NULL, 0)
+ "noddy.Noddy", /* tp_name */
+ sizeof(Noddy), /* tp_basicsize */
+ 0, /* tp_itemsize */
+ (destructor)Noddy_dealloc, /* tp_dealloc */
+ 0, /* tp_print */
+ 0, /* tp_getattr */
+ 0, /* tp_setattr */
+ 0, /* tp_compare */
+ 0, /* tp_repr */
+ 0, /* tp_as_number */
+ 0, /* tp_as_sequence */
+ 0, /* tp_as_mapping */
+ 0, /* tp_hash */
+ 0, /* tp_call */
+ 0, /* tp_str */
+ 0, /* tp_getattro */
+ 0, /* tp_setattro */
+ 0, /* tp_as_buffer */
+ Py_TPFLAGS_DEFAULT |
+ Py_TPFLAGS_BASETYPE, /* tp_flags */
"Noddy objects", /* tp_doc */
- 0, /* tp_traverse */
- 0, /* tp_clear */
- 0, /* tp_richcompare */
- 0, /* tp_weaklistoffset */
- 0, /* tp_iter */
- 0, /* tp_iternext */
+ 0, /* tp_traverse */
+ 0, /* tp_clear */
+ 0, /* tp_richcompare */
+ 0, /* tp_weaklistoffset */
+ 0, /* tp_iter */
+ 0, /* tp_iternext */
Noddy_methods, /* tp_methods */
Noddy_members, /* tp_members */
0, /* tp_getset */
#define PyMODINIT_FUNC void
#endif
PyMODINIT_FUNC
-initnoddy2(void)
+initnoddy2(void)
{
PyObject* m;
"Example module that creates an extension type.");
if (m == NULL)
- return;
+ return;
Py_INCREF(&NoddyType);
PyModule_AddObject(m, "Noddy", (PyObject *)&NoddyType);
{
Py_XDECREF(self->first);
Py_XDECREF(self->last);
- self->ob_type->tp_free((PyObject*)self);
+ Py_TYPE(self)->tp_free((PyObject*)self);
}
static PyObject *
self = (Noddy *)type->tp_alloc(type, 0);
if (self != NULL) {
self->first = PyString_FromString("");
- if (self->first == NULL)
- {
+ if (self->first == NULL) {
Py_DECREF(self);
return NULL;
- }
-
+ }
+
self->last = PyString_FromString("");
- if (self->last == NULL)
- {
+ if (self->last == NULL) {
Py_DECREF(self);
return NULL;
- }
+ }
self->number = 0;
}
static char *kwlist[] = {"first", "last", "number", NULL};
- if (! PyArg_ParseTupleAndKeywords(args, kwds, "|SSi", kwlist,
- &first, &last,
+ if (! PyArg_ParseTupleAndKeywords(args, kwds, "|SSi", kwlist,
+ &first, &last,
&self->number))
- return -1;
+ return -1;
if (first) {
tmp = self->first;
static int
Noddy_setfirst(Noddy *self, PyObject *value, void *closure)
{
- if (value == NULL) {
- PyErr_SetString(PyExc_TypeError, "Cannot delete the first attribute");
- return -1;
- }
-
- if (! PyString_Check(value)) {
- PyErr_SetString(PyExc_TypeError,
- "The first attribute value must be a string");
- return -1;
- }
-
- Py_DECREF(self->first);
- Py_INCREF(value);
- self->first = value;
-
- return 0;
+ if (value == NULL) {
+ PyErr_SetString(PyExc_TypeError, "Cannot delete the first attribute");
+ return -1;
+ }
+
+ if (! PyString_Check(value)) {
+ PyErr_SetString(PyExc_TypeError,
+ "The first attribute value must be a string");
+ return -1;
+ }
+
+ Py_DECREF(self->first);
+ Py_INCREF(value);
+ self->first = value;
+
+ return 0;
}
static PyObject *
static int
Noddy_setlast(Noddy *self, PyObject *value, void *closure)
{
- if (value == NULL) {
- PyErr_SetString(PyExc_TypeError, "Cannot delete the last attribute");
- return -1;
- }
-
- if (! PyString_Check(value)) {
- PyErr_SetString(PyExc_TypeError,
- "The last attribute value must be a string");
- return -1;
- }
-
- Py_DECREF(self->last);
- Py_INCREF(value);
- self->last = value;
-
- return 0;
+ if (value == NULL) {
+ PyErr_SetString(PyExc_TypeError, "Cannot delete the last attribute");
+ return -1;
+ }
+
+ if (! PyString_Check(value)) {
+ PyErr_SetString(PyExc_TypeError,
+ "The last attribute value must be a string");
+ return -1;
+ }
+
+ Py_DECREF(self->last);
+ Py_INCREF(value);
+ self->last = value;
+
+ return 0;
}
static PyGetSetDef Noddy_getseters[] = {
- {"first",
+ {"first",
(getter)Noddy_getfirst, (setter)Noddy_setfirst,
"first name",
NULL},
- {"last",
+ {"last",
(getter)Noddy_getlast, (setter)Noddy_setlast,
"last name",
NULL},
result = PyString_Format(format, args);
Py_DECREF(args);
-
+
return result;
}
};
static PyTypeObject NoddyType = {
- PyObject_HEAD_INIT(NULL)
- 0, /*ob_size*/
- "noddy.Noddy", /*tp_name*/
- sizeof(Noddy), /*tp_basicsize*/
- 0, /*tp_itemsize*/
- (destructor)Noddy_dealloc, /*tp_dealloc*/
- 0, /*tp_print*/
- 0, /*tp_getattr*/
- 0, /*tp_setattr*/
- 0, /*tp_compare*/
- 0, /*tp_repr*/
- 0, /*tp_as_number*/
- 0, /*tp_as_sequence*/
- 0, /*tp_as_mapping*/
- 0, /*tp_hash */
- 0, /*tp_call*/
- 0, /*tp_str*/
- 0, /*tp_getattro*/
- 0, /*tp_setattro*/
- 0, /*tp_as_buffer*/
- Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, /*tp_flags*/
+ PyVarObject_HEAD_INIT(NULL, 0)
+ "noddy.Noddy", /* tp_name */
+ sizeof(Noddy), /* tp_basicsize */
+ 0, /* tp_itemsize */
+ (destructor)Noddy_dealloc, /* tp_dealloc */
+ 0, /* tp_print */
+ 0, /* tp_getattr */
+ 0, /* tp_setattr */
+ 0, /* tp_compare */
+ 0, /* tp_repr */
+ 0, /* tp_as_number */
+ 0, /* tp_as_sequence */
+ 0, /* tp_as_mapping */
+ 0, /* tp_hash */
+ 0, /* tp_call */
+ 0, /* tp_str */
+ 0, /* tp_getattro */
+ 0, /* tp_setattro */
+ 0, /* tp_as_buffer */
+ Py_TPFLAGS_DEFAULT |
+ Py_TPFLAGS_BASETYPE, /* tp_flags */
"Noddy objects", /* tp_doc */
- 0, /* tp_traverse */
- 0, /* tp_clear */
- 0, /* tp_richcompare */
- 0, /* tp_weaklistoffset */
- 0, /* tp_iter */
- 0, /* tp_iternext */
+ 0, /* tp_traverse */
+ 0, /* tp_clear */
+ 0, /* tp_richcompare */
+ 0, /* tp_weaklistoffset */
+ 0, /* tp_iter */
+ 0, /* tp_iternext */
Noddy_methods, /* tp_methods */
Noddy_members, /* tp_members */
Noddy_getseters, /* tp_getset */
#define PyMODINIT_FUNC void
#endif
PyMODINIT_FUNC
-initnoddy3(void)
+initnoddy3(void)
{
PyObject* m;
"Example module that creates an extension type.");
if (m == NULL)
- return;
+ return;
Py_INCREF(&NoddyType);
PyModule_AddObject(m, "Noddy", (PyObject *)&NoddyType);
return 0;
}
-static int
+static int
Noddy_clear(Noddy *self)
{
PyObject *tmp;
Noddy_dealloc(Noddy* self)
{
Noddy_clear(self);
- self->ob_type->tp_free((PyObject*)self);
+ Py_TYPE(self)->tp_free((PyObject*)self);
}
static PyObject *
self = (Noddy *)type->tp_alloc(type, 0);
if (self != NULL) {
self->first = PyString_FromString("");
- if (self->first == NULL)
- {
+ if (self->first == NULL) {
Py_DECREF(self);
return NULL;
- }
-
+ }
+
self->last = PyString_FromString("");
- if (self->last == NULL)
- {
+ if (self->last == NULL) {
Py_DECREF(self);
return NULL;
- }
+ }
self->number = 0;
}
static char *kwlist[] = {"first", "last", "number", NULL};
- if (! PyArg_ParseTupleAndKeywords(args, kwds, "|OOi", kwlist,
- &first, &last,
+ if (! PyArg_ParseTupleAndKeywords(args, kwds, "|OOi", kwlist,
+ &first, &last,
&self->number))
- return -1;
+ return -1;
if (first) {
tmp = self->first;
result = PyString_Format(format, args);
Py_DECREF(args);
-
+
return result;
}
};
static PyTypeObject NoddyType = {
- PyObject_HEAD_INIT(NULL)
- 0, /*ob_size*/
- "noddy.Noddy", /*tp_name*/
- sizeof(Noddy), /*tp_basicsize*/
- 0, /*tp_itemsize*/
- (destructor)Noddy_dealloc, /*tp_dealloc*/
- 0, /*tp_print*/
- 0, /*tp_getattr*/
- 0, /*tp_setattr*/
- 0, /*tp_compare*/
- 0, /*tp_repr*/
- 0, /*tp_as_number*/
- 0, /*tp_as_sequence*/
- 0, /*tp_as_mapping*/
- 0, /*tp_hash */
- 0, /*tp_call*/
- 0, /*tp_str*/
- 0, /*tp_getattro*/
- 0, /*tp_setattro*/
- 0, /*tp_as_buffer*/
- Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE | Py_TPFLAGS_HAVE_GC, /*tp_flags*/
+ PyVarObject_HEAD_INIT(NULL, 0)
+ "noddy.Noddy", /* tp_name */
+ sizeof(Noddy), /* tp_basicsize */
+ 0, /* tp_itemsize */
+ (destructor)Noddy_dealloc, /* tp_dealloc */
+ 0, /* tp_print */
+ 0, /* tp_getattr */
+ 0, /* tp_setattr */
+ 0, /* tp_compare */
+ 0, /* tp_repr */
+ 0, /* tp_as_number */
+ 0, /* tp_as_sequence */
+ 0, /* tp_as_mapping */
+ 0, /* tp_hash */
+ 0, /* tp_call */
+ 0, /* tp_str */
+ 0, /* tp_getattro */
+ 0, /* tp_setattro */
+ 0, /* tp_as_buffer */
+ Py_TPFLAGS_DEFAULT |
+ Py_TPFLAGS_BASETYPE |
+ Py_TPFLAGS_HAVE_GC, /* tp_flags */
"Noddy objects", /* tp_doc */
(traverseproc)Noddy_traverse, /* tp_traverse */
(inquiry)Noddy_clear, /* tp_clear */
- 0, /* tp_richcompare */
- 0, /* tp_weaklistoffset */
- 0, /* tp_iter */
- 0, /* tp_iternext */
+ 0, /* tp_richcompare */
+ 0, /* tp_weaklistoffset */
+ 0, /* tp_iter */
+ 0, /* tp_iternext */
Noddy_methods, /* tp_methods */
Noddy_members, /* tp_members */
0, /* tp_getset */
#define PyMODINIT_FUNC void
#endif
PyMODINIT_FUNC
-initnoddy4(void)
+initnoddy4(void)
{
PyObject* m;
"Example module that creates an extension type.");
if (m == NULL)
- return;
+ return;
Py_INCREF(&NoddyType);
PyModule_AddObject(m, "Noddy", (PyObject *)&NoddyType);
Extension("noddy2", ["noddy2.c"]),
Extension("noddy3", ["noddy3.c"]),
Extension("noddy4", ["noddy4.c"]),
+ Extension("shoddy", ["shoddy.c"]),
])
static PyTypeObject ShoddyType = {
- PyObject_HEAD_INIT(NULL)
- 0, /* ob_size */
+ PyVarObject_HEAD_INIT(NULL, 0)
"shoddy.Shoddy", /* tp_name */
sizeof(Shoddy), /* tp_basicsize */
0, /* tp_itemsize */
0, /* tp_setattro */
0, /* tp_as_buffer */
Py_TPFLAGS_DEFAULT |
- Py_TPFLAGS_BASETYPE, /* tp_flags */
+ Py_TPFLAGS_BASETYPE, /* tp_flags */
0, /* tp_doc */
0, /* tp_traverse */
0, /* tp_clear */
projects / python / commitdiff