/Doc/includes/noddy2.c

  1#include <Python.h>
  2#include "structmember.h"
  3
  4typedef struct {
  5    PyObject_HEAD
  6    PyObject *first; /* first name */
  7    PyObject *last;  /* last name */
  8    int number;
  9} Noddy;
 10
 11static void
 12Noddy_dealloc(Noddy* self)
 13{
 14    Py_XDECREF(self->first);
 15    Py_XDECREF(self->last);
 16    self->ob_type->tp_free((PyObject*)self);
 17}
 18
 19static PyObject *
 20Noddy_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
 21{
 22    Noddy *self;
 23
 24    self = (Noddy *)type->tp_alloc(type, 0);
 25    if (self != NULL) {
 26        self->first = PyString_FromString("");
 27        if (self->first == NULL)
 28          {
 29            Py_DECREF(self);
 30            return NULL;
 31          }
 32        
 33        self->last = PyString_FromString("");
 34        if (self->last == NULL)
 35          {
 36            Py_DECREF(self);
 37            return NULL;
 38          }
 39
 40        self->number = 0;
 41    }
 42
 43    return (PyObject *)self;
 44}
 45
 46static int
 47Noddy_init(Noddy *self, PyObject *args, PyObject *kwds)
 48{
 49    PyObject *first=NULL, *last=NULL, *tmp;
 50
 51    static char *kwlist[] = {"first", "last", "number", NULL};
 52
 53    if (! PyArg_ParseTupleAndKeywords(args, kwds, "|OOi", kwlist, 
 54                                      &first, &last, 
 55                                      &self->number))
 56        return -1; 
 57
 58    if (first) {
 59        tmp = self->first;
 60        Py_INCREF(first);
 61        self->first = first;
 62        Py_XDECREF(tmp);
 63    }
 64
 65    if (last) {
 66        tmp = self->last;
 67        Py_INCREF(last);
 68        self->last = last;
 69        Py_XDECREF(tmp);
 70    }
 71
 72    return 0;
 73}
 74
 75
 76static PyMemberDef Noddy_members[] = {
 77    {"first", T_OBJECT_EX, offsetof(Noddy, first), 0,
 78     "first name"},
 79    {"last", T_OBJECT_EX, offsetof(Noddy, last), 0,
 80     "last name"},
 81    {"number", T_INT, offsetof(Noddy, number), 0,
 82     "noddy number"},
 83    {NULL}  /* Sentinel */
 84};
 85
 86static PyObject *
 87Noddy_name(Noddy* self)
 88{
 89    static PyObject *format = NULL;
 90    PyObject *args, *result;
 91
 92    if (format == NULL) {
 93        format = PyString_FromString("%s %s");
 94        if (format == NULL)
 95            return NULL;
 96    }
 97
 98    if (self->first == NULL) {
 99        PyErr_SetString(PyExc_AttributeError, "first");
100        return NULL;
101    }
102
103    if (self->last == NULL) {
104        PyErr_SetString(PyExc_AttributeError, "last");
105        return NULL;
106    }
107
108    args = Py_BuildValue("OO", self->first, self->last);
109    if (args == NULL)
110        return NULL;
111
112    result = PyString_Format(format, args);
113    Py_DECREF(args);
114    
115    return result;
116}
117
118static PyMethodDef Noddy_methods[] = {
119    {"name", (PyCFunction)Noddy_name, METH_NOARGS,
120     "Return the name, combining the first and last name"
121    },
122    {NULL}  /* Sentinel */
123};
124
125static PyTypeObject NoddyType = {
126    PyObject_HEAD_INIT(NULL)
127    0,                         /*ob_size*/
128    "noddy.Noddy",             /*tp_name*/
129    sizeof(Noddy),             /*tp_basicsize*/
130    0,                         /*tp_itemsize*/
131    (destructor)Noddy_dealloc, /*tp_dealloc*/
132    0,                         /*tp_print*/
133    0,                         /*tp_getattr*/
134    0,                         /*tp_setattr*/
135    0,                         /*tp_compare*/
136    0,                         /*tp_repr*/
137    0,                         /*tp_as_number*/
138    0,                         /*tp_as_sequence*/
139    0,                         /*tp_as_mapping*/
140    0,                         /*tp_hash */
141    0,                         /*tp_call*/
142    0,                         /*tp_str*/
143    0,                         /*tp_getattro*/
144    0,                         /*tp_setattro*/
145    0,                         /*tp_as_buffer*/
146    Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, /*tp_flags*/
147    "Noddy objects",           /* tp_doc */
148    0,		               /* tp_traverse */
149    0,		               /* tp_clear */
150    0,		               /* tp_richcompare */
151    0,		               /* tp_weaklistoffset */
152    0,		               /* tp_iter */
153    0,		               /* tp_iternext */
154    Noddy_methods,             /* tp_methods */
155    Noddy_members,             /* tp_members */
156    0,                         /* tp_getset */
157    0,                         /* tp_base */
158    0,                         /* tp_dict */
159    0,                         /* tp_descr_get */
160    0,                         /* tp_descr_set */
161    0,                         /* tp_dictoffset */
162    (initproc)Noddy_init,      /* tp_init */
163    0,                         /* tp_alloc */
164    Noddy_new,                 /* tp_new */
165};
166
167static PyMethodDef module_methods[] = {
168    {NULL}  /* Sentinel */
169};
170
171#ifndef PyMODINIT_FUNC	/* declarations for DLL import/export */
172#define PyMODINIT_FUNC void
173#endif
174PyMODINIT_FUNC
175initnoddy2(void) 
176{
177    PyObject* m;
178
179    if (PyType_Ready(&NoddyType) < 0)
180        return;
181
182    m = Py_InitModule3("noddy2", module_methods,
183                       "Example module that creates an extension type.");
184
185    if (m == NULL)
186      return;
187
188    Py_INCREF(&NoddyType);
189    PyModule_AddObject(m, "Noddy", (PyObject *)&NoddyType);
190}