#define PY_SSIZE_T_CLEAN
#include <Python.h>
#include "structmember.h"

typedef struct {
 PyObject_HEAD
 PyObject *first; /* first name */
 PyObject *last; /* last name */
 int number;
} CustomObject;

static void
Custom_dealloc(CustomObject *self)
{
 Py_XDECREF(self->first);
 Py_XDECREF(self->last);
 Py_TYPE(self)->tp_free((PyObject *) self);
}

static PyObject *
Custom_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
{
 CustomObject *self;
 self = (CustomObject *) type->tp_alloc(type, 0);
 if (self != NULL) {
 self->first = PyUnicode_FromString("");
 if (self->first == NULL) {
 Py_DECREF(self);
 return NULL;
 }
 self->last = PyUnicode_FromString("");
 if (self->last == NULL) {
 Py_DECREF(self);
 return NULL;
 }
 self->number = 0;
 }
 return (PyObject *) self;
}

static int
Custom_init(CustomObject *self, PyObject *args, PyObject *kwds)
{
 static char *kwlist[] = {"first", "last", "number", NULL};
 PyObject *first = NULL, *last = NULL, *tmp;

 if (!PyArg_ParseTupleAndKeywords(args, kwds, "|OOi", kwlist,
 &first, &last,
 &self->number))
 return -1;

 if (first) {
 tmp = self->first;
 Py_INCREF(first);
 self->first = first;
 Py_XDECREF(tmp);
 }
 if (last) {
 tmp = self->last;
 Py_INCREF(last);
 self->last = last;
 Py_XDECREF(tmp);
 }
 return 0;
}

static PyMemberDef Custom_members[] = {
 {"first", T_OBJECT_EX, offsetof(CustomObject, first), 0,
 "first name"},
 {"last", T_OBJECT_EX, offsetof(CustomObject, last), 0,
 "last name"},
 {"number", T_INT, offsetof(CustomObject, number), 0,
 "custom number"},
 {NULL} /* Sentinel */
};

static PyObject *
Custom_name(CustomObject *self, PyObject *Py_UNUSED(ignored))
{
 if (self->first == NULL) {
 PyErr_SetString(PyExc_AttributeError, "first");
 return NULL;
 }
 if (self->last == NULL) {
 PyErr_SetString(PyExc_AttributeError, "last");
 return NULL;
 }
 return PyUnicode_FromFormat("%S %S", self->first, self->last);
}

static PyMethodDef Custom_methods[] = {
 {"name", (PyCFunction) Custom_name, METH_NOARGS,
 "Return the name, combining the first and last name"
 },
 {NULL} /* Sentinel */
};

static PyTypeObject CustomType = {
 PyVarObject_HEAD_INIT(NULL, 0)
 .tp_name = "custom2.Custom",
 .tp_doc = "Custom objects",
 .tp_basicsize = sizeof(CustomObject),
 .tp_itemsize = 0,
 .tp_flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE,
 .tp_new = Custom_new,
 .tp_init = (initproc) Custom_init,
 .tp_dealloc = (destructor) Custom_dealloc,
 .tp_members = Custom_members,
 .tp_methods = Custom_methods,
};

static PyModuleDef custommodule = {
 PyModuleDef_HEAD_INIT,
 .m_name = "custom2",
 .m_doc = "Example module that creates an extension type.",
 .m_size = -1,
};

PyMODINIT_FUNC
PyInit_custom2(void)
{
 PyObject *m;
 if (PyType_Ready(&CustomType) < 0)
 return NULL;

 m = PyModule_Create(&custommodule);
 if (m == NULL)
 return NULL;

 Py_INCREF(&CustomType);
 PyModule_AddObject(m, "Custom", (PyObject *) &CustomType);
 return m;
}