Doc/includes/noddy2.c

   1 #include <Python.h>
   2 #include "structmember.h"
   3
   4 typedef struct {
   5     PyObject_HEAD
   6     PyObject *first; /* first name */
   7     PyObject *last;  /* last name */
   8     int number;
   9 } Noddy;
  10
  11 static void
  12 Noddy_dealloc(Noddy* self)
  13 {
  14     Py_XDECREF(self->first);
  15     Py_XDECREF(self->last);
  16     self->ob_type->tp_free((PyObject*)self);
  17 }
  18
  19 static PyObject *
  20 Noddy_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
  46 static int
  47 Noddy_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
  76 static 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
  86 static PyObject *
  87 Noddy_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
 118 static 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
 125 static 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
 167 static PyMethodDef module_methods[] = {
 168     {NULL}  /* Sentinel */
 169 };
 170
 171 #ifndef PyMODINIT_FUNC  /* declarations for DLL import/export */
 172 #define PyMODINIT_FUNC void
 173 #endif
 174 PyMODINIT_FUNC
 175 initnoddy2(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 }