1
2 /* Use this file as a template to start implementing a module that
3 also declares object types. All occurrences of 'Xxo' should be changed
4 to something reasonable for your objects. After that, all other
5 occurrences of 'xx' should be changed to something reasonable for your
6 module. If your module is named foo your sourcefile should be named
7 foomodule.c.
8
9 You will probably want to delete all references to 'x_attr' and add
10 your own types of attributes instead. Maybe you want to name your
11 local variables other than 'self'. If your object type is needed in
12 other files, you'll have to create a file "foobarobject.h"; see
13 floatobject.h for an example. */
14
15 /* Xxo objects */
16
17 #include "Python.h"
18
19 static PyObject *ErrorObject;
20
21 typedef struct {
22 PyObject_HEAD
23 PyObject *x_attr; /* Attributes dictionary */
24 } XxoObject;
25
26 static PyTypeObject Xxo_Type;
27
28 #define XxoObject_Check(v) (Py_TYPE(v) == &Xxo_Type)
29
30 static XxoObject *
newXxoObject(PyObject * arg)31 newXxoObject(PyObject *arg)
32 {
33 XxoObject *self;
34 self = PyObject_New(XxoObject, &Xxo_Type);
35 if (self == NULL)
36 return NULL;
37 self->x_attr = NULL;
38 return self;
39 }
40
41 /* Xxo methods */
42
43 static void
Xxo_dealloc(XxoObject * self)44 Xxo_dealloc(XxoObject *self)
45 {
46 Py_XDECREF(self->x_attr);
47 PyObject_Del(self);
48 }
49
50 static PyObject *
Xxo_demo(XxoObject * self,PyObject * args)51 Xxo_demo(XxoObject *self, PyObject *args)
52 {
53 if (!PyArg_ParseTuple(args, ":demo"))
54 return NULL;
55 Py_INCREF(Py_None);
56 return Py_None;
57 }
58
59 static PyMethodDef Xxo_methods[] = {
60 {"demo", (PyCFunction)Xxo_demo, METH_VARARGS,
61 PyDoc_STR("demo() -> None")},
62 {NULL, NULL} /* sentinel */
63 };
64
65 static PyObject *
Xxo_getattro(XxoObject * self,PyObject * name)66 Xxo_getattro(XxoObject *self, PyObject *name)
67 {
68 if (self->x_attr != NULL) {
69 PyObject *v = PyDict_GetItem(self->x_attr, name);
70 if (v != NULL) {
71 Py_INCREF(v);
72 return v;
73 }
74 }
75 return PyObject_GenericGetAttr((PyObject *)self, name);
76 }
77
78 static int
Xxo_setattr(XxoObject * self,const char * name,PyObject * v)79 Xxo_setattr(XxoObject *self, const char *name, PyObject *v)
80 {
81 if (self->x_attr == NULL) {
82 self->x_attr = PyDict_New();
83 if (self->x_attr == NULL)
84 return -1;
85 }
86 if (v == NULL) {
87 int rv = PyDict_DelItemString(self->x_attr, name);
88 if (rv < 0)
89 PyErr_SetString(PyExc_AttributeError,
90 "delete non-existing Xxo attribute");
91 return rv;
92 }
93 else
94 return PyDict_SetItemString(self->x_attr, name, v);
95 }
96
97 static PyTypeObject Xxo_Type = {
98 /* The ob_type field must be initialized in the module init function
99 * to be portable to Windows without using C++. */
100 PyVarObject_HEAD_INIT(NULL, 0)
101 "xxmodule.Xxo", /*tp_name*/
102 sizeof(XxoObject), /*tp_basicsize*/
103 0, /*tp_itemsize*/
104 /* methods */
105 (destructor)Xxo_dealloc, /*tp_dealloc*/
106 0, /*tp_print*/
107 (getattrfunc)0, /*tp_getattr*/
108 (setattrfunc)Xxo_setattr, /*tp_setattr*/
109 0, /*tp_reserved*/
110 0, /*tp_repr*/
111 0, /*tp_as_number*/
112 0, /*tp_as_sequence*/
113 0, /*tp_as_mapping*/
114 0, /*tp_hash*/
115 0, /*tp_call*/
116 0, /*tp_str*/
117 (getattrofunc)Xxo_getattro, /*tp_getattro*/
118 0, /*tp_setattro*/
119 0, /*tp_as_buffer*/
120 Py_TPFLAGS_DEFAULT, /*tp_flags*/
121 0, /*tp_doc*/
122 0, /*tp_traverse*/
123 0, /*tp_clear*/
124 0, /*tp_richcompare*/
125 0, /*tp_weaklistoffset*/
126 0, /*tp_iter*/
127 0, /*tp_iternext*/
128 Xxo_methods, /*tp_methods*/
129 0, /*tp_members*/
130 0, /*tp_getset*/
131 0, /*tp_base*/
132 0, /*tp_dict*/
133 0, /*tp_descr_get*/
134 0, /*tp_descr_set*/
135 0, /*tp_dictoffset*/
136 0, /*tp_init*/
137 0, /*tp_alloc*/
138 0, /*tp_new*/
139 0, /*tp_free*/
140 0, /*tp_is_gc*/
141 };
142 /* --------------------------------------------------------------------- */
143
144 /* Function of two integers returning integer */
145
146 PyDoc_STRVAR(xx_foo_doc,
147 "foo(i,j)\n\
148 \n\
149 Return the sum of i and j.");
150
151 static PyObject *
xx_foo(PyObject * self,PyObject * args)152 xx_foo(PyObject *self, PyObject *args)
153 {
154 long i, j;
155 long res;
156 if (!PyArg_ParseTuple(args, "ll:foo", &i, &j))
157 return NULL;
158 res = i+j; /* XXX Do something here */
159 return PyLong_FromLong(res);
160 }
161
162
163 /* Function of no arguments returning new Xxo object */
164
165 static PyObject *
xx_new(PyObject * self,PyObject * args)166 xx_new(PyObject *self, PyObject *args)
167 {
168 XxoObject *rv;
169
170 if (!PyArg_ParseTuple(args, ":new"))
171 return NULL;
172 rv = newXxoObject(args);
173 if (rv == NULL)
174 return NULL;
175 return (PyObject *)rv;
176 }
177
178 /* Example with subtle bug from extensions manual ("Thin Ice"). */
179
180 static PyObject *
xx_bug(PyObject * self,PyObject * args)181 xx_bug(PyObject *self, PyObject *args)
182 {
183 PyObject *list, *item;
184
185 if (!PyArg_ParseTuple(args, "O:bug", &list))
186 return NULL;
187
188 item = PyList_GetItem(list, 0);
189 /* Py_INCREF(item); */
190 PyList_SetItem(list, 1, PyLong_FromLong(0L));
191 PyObject_Print(item, stdout, 0);
192 printf("\n");
193 /* Py_DECREF(item); */
194
195 Py_INCREF(Py_None);
196 return Py_None;
197 }
198
199 /* Test bad format character */
200
201 static PyObject *
xx_roj(PyObject * self,PyObject * args)202 xx_roj(PyObject *self, PyObject *args)
203 {
204 PyObject *a;
205 long b;
206 if (!PyArg_ParseTuple(args, "O#:roj", &a, &b))
207 return NULL;
208 Py_INCREF(Py_None);
209 return Py_None;
210 }
211
212
213 /* ---------- */
214
215 static PyTypeObject Str_Type = {
216 /* The ob_type field must be initialized in the module init function
217 * to be portable to Windows without using C++. */
218 PyVarObject_HEAD_INIT(NULL, 0)
219 "xxmodule.Str", /*tp_name*/
220 0, /*tp_basicsize*/
221 0, /*tp_itemsize*/
222 /* methods */
223 0, /*tp_dealloc*/
224 0, /*tp_print*/
225 0, /*tp_getattr*/
226 0, /*tp_setattr*/
227 0, /*tp_reserved*/
228 0, /*tp_repr*/
229 0, /*tp_as_number*/
230 0, /*tp_as_sequence*/
231 0, /*tp_as_mapping*/
232 0, /*tp_hash*/
233 0, /*tp_call*/
234 0, /*tp_str*/
235 0, /*tp_getattro*/
236 0, /*tp_setattro*/
237 0, /*tp_as_buffer*/
238 Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, /*tp_flags*/
239 0, /*tp_doc*/
240 0, /*tp_traverse*/
241 0, /*tp_clear*/
242 0, /*tp_richcompare*/
243 0, /*tp_weaklistoffset*/
244 0, /*tp_iter*/
245 0, /*tp_iternext*/
246 0, /*tp_methods*/
247 0, /*tp_members*/
248 0, /*tp_getset*/
249 0, /* see PyInit_xx */ /*tp_base*/
250 0, /*tp_dict*/
251 0, /*tp_descr_get*/
252 0, /*tp_descr_set*/
253 0, /*tp_dictoffset*/
254 0, /*tp_init*/
255 0, /*tp_alloc*/
256 0, /*tp_new*/
257 0, /*tp_free*/
258 0, /*tp_is_gc*/
259 };
260
261 /* ---------- */
262
263 static PyObject *
null_richcompare(PyObject * self,PyObject * other,int op)264 null_richcompare(PyObject *self, PyObject *other, int op)
265 {
266 Py_INCREF(Py_NotImplemented);
267 return Py_NotImplemented;
268 }
269
270 static PyTypeObject Null_Type = {
271 /* The ob_type field must be initialized in the module init function
272 * to be portable to Windows without using C++. */
273 PyVarObject_HEAD_INIT(NULL, 0)
274 "xxmodule.Null", /*tp_name*/
275 0, /*tp_basicsize*/
276 0, /*tp_itemsize*/
277 /* methods */
278 0, /*tp_dealloc*/
279 0, /*tp_print*/
280 0, /*tp_getattr*/
281 0, /*tp_setattr*/
282 0, /*tp_reserved*/
283 0, /*tp_repr*/
284 0, /*tp_as_number*/
285 0, /*tp_as_sequence*/
286 0, /*tp_as_mapping*/
287 0, /*tp_hash*/
288 0, /*tp_call*/
289 0, /*tp_str*/
290 0, /*tp_getattro*/
291 0, /*tp_setattro*/
292 0, /*tp_as_buffer*/
293 Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE, /*tp_flags*/
294 0, /*tp_doc*/
295 0, /*tp_traverse*/
296 0, /*tp_clear*/
297 null_richcompare, /*tp_richcompare*/
298 0, /*tp_weaklistoffset*/
299 0, /*tp_iter*/
300 0, /*tp_iternext*/
301 0, /*tp_methods*/
302 0, /*tp_members*/
303 0, /*tp_getset*/
304 0, /* see PyInit_xx */ /*tp_base*/
305 0, /*tp_dict*/
306 0, /*tp_descr_get*/
307 0, /*tp_descr_set*/
308 0, /*tp_dictoffset*/
309 0, /*tp_init*/
310 0, /*tp_alloc*/
311 0, /* see PyInit_xx */ /*tp_new*/
312 0, /*tp_free*/
313 0, /*tp_is_gc*/
314 };
315
316
317 /* ---------- */
318
319
320 /* List of functions defined in the module */
321
322 static PyMethodDef xx_methods[] = {
323 {"roj", xx_roj, METH_VARARGS,
324 PyDoc_STR("roj(a,b) -> None")},
325 {"foo", xx_foo, METH_VARARGS,
326 xx_foo_doc},
327 {"new", xx_new, METH_VARARGS,
328 PyDoc_STR("new() -> new Xx object")},
329 {"bug", xx_bug, METH_VARARGS,
330 PyDoc_STR("bug(o) -> None")},
331 {NULL, NULL} /* sentinel */
332 };
333
334 PyDoc_STRVAR(module_doc,
335 "This is a template module just for instruction.");
336
337
338 static int
xx_exec(PyObject * m)339 xx_exec(PyObject *m)
340 {
341 /* Due to cross platform compiler issues the slots must be filled
342 * here. It's required for portability to Windows without requiring
343 * C++. */
344 Null_Type.tp_base = &PyBaseObject_Type;
345 Null_Type.tp_new = PyType_GenericNew;
346 Str_Type.tp_base = &PyUnicode_Type;
347
348 /* Finalize the type object including setting type of the new type
349 * object; doing it here is required for portability, too. */
350 if (PyType_Ready(&Xxo_Type) < 0)
351 goto fail;
352
353 /* Add some symbolic constants to the module */
354 if (ErrorObject == NULL) {
355 ErrorObject = PyErr_NewException("xx.error", NULL, NULL);
356 if (ErrorObject == NULL)
357 goto fail;
358 }
359 Py_INCREF(ErrorObject);
360 PyModule_AddObject(m, "error", ErrorObject);
361
362 /* Add Str */
363 if (PyType_Ready(&Str_Type) < 0)
364 goto fail;
365 PyModule_AddObject(m, "Str", (PyObject *)&Str_Type);
366
367 /* Add Null */
368 if (PyType_Ready(&Null_Type) < 0)
369 goto fail;
370 PyModule_AddObject(m, "Null", (PyObject *)&Null_Type);
371 return 0;
372 fail:
373 Py_XDECREF(m);
374 return -1;
375 }
376
377 static struct PyModuleDef_Slot xx_slots[] = {
378 {Py_mod_exec, xx_exec},
379 {0, NULL},
380 };
381
382 static struct PyModuleDef xxmodule = {
383 PyModuleDef_HEAD_INIT,
384 "xx",
385 module_doc,
386 0,
387 xx_methods,
388 xx_slots,
389 NULL,
390 NULL,
391 NULL
392 };
393
394 /* Export function for the module (*must* be called PyInit_xx) */
395
396 PyMODINIT_FUNC
PyInit_xx(void)397 PyInit_xx(void)
398 {
399 return PyModuleDef_Init(&xxmodule);
400 }
401