Objects/xxobject.c

   1 /***********************************************************
   2 Copyright 1991-1995 by Stichting Mathematisch Centrum, Amsterdam,
   3 The Netherlands.
   4
   5                         All Rights Reserved
   6
   7 Permission to use, copy, modify, and distribute this software and its
   8 documentation for any purpose and without fee is hereby granted,
   9 provided that the above copyright notice appear in all copies and that
  10 both that copyright notice and this permission notice appear in
  11 supporting documentation, and that the names of Stichting Mathematisch
  12 Centrum or CWI not be used in advertising or publicity pertaining to
  13 distribution of the software without specific, written prior permission.
  14
  15 STICHTING MATHEMATISCH CENTRUM DISCLAIMS ALL WARRANTIES WITH REGARD TO
  16 THIS SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
  17 FITNESS, IN NO EVENT SHALL STICHTING MATHEMATISCH CENTRUM BE LIABLE
  18 FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  19 WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  20 ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
  21 OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  22
  23 ******************************************************************/
  24
  25 /* Use this file as a template to start implementing a new object type.
  26    If your objects will be called foobar, start by copying this file to
  27    foobarobject.c, changing all occurrences of xx to foobar and all
  28    occurrences of Xx by Foobar.  You will probably want to delete all
  29    references to 'x_attr' and add your own types of attributes
  30    instead.  Maybe you want to name your local variables other than
  31    'xp'.  If your object type is needed in other files, you'll have to
  32    create a file "foobarobject.h"; see intobject.h for an example. */
  33
  34
  35 /* Xx objects */
  36
  37 #include "Python.h"
  38
  39 typedef struct {
  40         PyObject_HEAD
  41         PyObject        *x_attr;        /* Attributes dictionary */
  42 } xxobject;
  43
  44 staticforward PyTypeObject Xxtype;
  45
  46 #define is_xxobject(v)          ((v)->ob_type == &Xxtype)
  47
  48 static xxobject *
  49 newxxobject(arg)
  50         PyObject *arg;
  51 {
  52         xxobject *xp;
  53         xp = PyObject_NEW(xxobject, &Xxtype);
  54         if (xp == NULL)
  55                 return NULL;
  56         xp->x_attr = NULL;
  57         return xp;
  58 }
  59
  60 /* Xx methods */
  61
  62 static void
  63 xx_dealloc(xp)
  64         xxobject *xp;
  65 {
  66         Py_XDECREF(xp->x_attr);
  67         PyMem_DEL(xp);
  68 }
  69
  70 static PyObject *
  71 xx_demo(self, args)
  72         xxobject *self;
  73         PyObject *args;
  74 {
  75         if (!PyArg_NoArgs(args))
  76                 return NULL;
  77         Py_INCREF(Py_None);
  78         return Py_None;
  79 }
  80
  81 static Py_MethodDef xx_methods[] = {
  82         {"demo",        (PyCFunction)xx_demo},
  83         {NULL,          NULL}           /* sentinel */
  84 };
  85
  86 static PyObject *
  87 xx_getattr(xp, name)
  88         xxobject *xp;
  89         char *name;
  90 {
  91         if (xp->x_attr != NULL) {
  92                 PyObject *v = PyDict_GetItemString(xp->x_attr, name);
  93                 if (v != NULL) {
  94                         Py_INCREF(v);
  95                         return v;
  96                 }
  97         }
  98         return Py_FindMethod(xx_methods, (PyObject *)xp, name);
  99 }
 100
 101 static int
 102 xx_setattr(xp, name, v)
 103         xxobject *xp;
 104         char *name;
 105         PyObject *v;
 106 {
 107         if (xp->x_attr == NULL) {
 108                 xp->x_attr = PyDict_New();
 109                 if (xp->x_attr == NULL)
 110                         return -1;
 111         }
 112         if (v == NULL) {
 113                 int rv = PyDict_DelItemString(xp->x_attr, name);
 114                 if (rv < 0)
 115                         PyErr_SetString(PyExc_AttributeError,
 116                                 "delete non-existing xx attribute");
 117                 return rv;
 118         }
 119         else
 120                 return PyDict_SetItemString(xp->x_attr, name, v);
 121 }
 122
 123 static PyTypeObject Xxtype = {
 124         PyObject_HEAD_INIT(&PyType_Type)
 125         0,                      /*ob_size*/
 126         "xx",                   /*tp_name*/
 127         sizeof(xxobject),       /*tp_basicsize*/
 128         0,                      /*tp_itemsize*/
 129         /* methods */
 130         (destructor)xx_dealloc, /*tp_dealloc*/
 131         0,                      /*tp_print*/
 132         (getattrfunc)xx_getattr, /*tp_getattr*/
 133         (setattrfunc)xx_setattr, /*tp_setattr*/
 134         0,                      /*tp_compare*/
 135         0,                      /*tp_repr*/
 136         0,                      /*tp_as_number*/
 137         0,                      /*tp_as_sequence*/
 138         0,                      /*tp_as_mapping*/
 139         0,                      /*tp_hash*/
 140 };