Objects/xxobject.c

   1 /***********************************************************
   2 Copyright 1991, 1992, 1993, 1994 by Stichting Mathematisch Centrum,
   3 Amsterdam, 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 "allobjects.h"
  38 #include "modsupport.h"         /* For getargs() etc. */
  39
  40 typedef struct {
  41         OB_HEAD
  42         object  *x_attr;        /* Attributes dictionary */
  43 } xxobject;
  44
  45 staticforward typeobject Xxtype;
  46
  47 #define is_xxobject(v)          ((v)->ob_type == &Xxtype)
  48
  49 static xxobject *
  50 newxxobject(arg)
  51         object *arg;
  52 {
  53         xxobject *xp;
  54         xp = NEWOBJ(xxobject, &Xxtype);
  55         if (xp == NULL)
  56                 return NULL;
  57         xp->x_attr = NULL;
  58         return xp;
  59 }
  60
  61 /* Xx methods */
  62
  63 static void
  64 xx_dealloc(xp)
  65         xxobject *xp;
  66 {
  67         XDECREF(xp->x_attr);
  68         DEL(xp);
  69 }
  70
  71 static object *
  72 xx_demo(self, args)
  73         xxobject *self;
  74         object *args;
  75 {
  76         if (!getnoarg(args))
  77                 return NULL;
  78         INCREF(None);
  79         return None;
  80 }
  81
  82 static struct methodlist xx_methods[] = {
  83         {"demo",        (method)xx_demo},
  84         {NULL,          NULL}           /* sentinel */
  85 };
  86
  87 static object *
  88 xx_getattr(xp, name)
  89         xxobject *xp;
  90         char *name;
  91 {
  92         if (xp->x_attr != NULL) {
  93                 object *v = dictlookup(xp->x_attr, name);
  94                 if (v != NULL) {
  95                         INCREF(v);
  96                         return v;
  97                 }
  98         }
  99         return findmethod(xx_methods, (object *)xp, name);
 100 }
 101
 102 static int
 103 xx_setattr(xp, name, v)
 104         xxobject *xp;
 105         char *name;
 106         object *v;
 107 {
 108         if (xp->x_attr == NULL) {
 109                 xp->x_attr = newdictobject();
 110                 if (xp->x_attr == NULL)
 111                         return -1;
 112         }
 113         if (v == NULL) {
 114                 int rv = dictremove(xp->x_attr, name);
 115                 if (rv < 0)
 116                         err_setstr(AttributeError,
 117                                 "delete non-existing xx attribute");
 118                 return rv;
 119         }
 120         else
 121                 return dictinsert(xp->x_attr, name, v);
 122 }
 123
 124 static typeobject Xxtype = {
 125         OB_HEAD_INIT(&Typetype)
 126         0,                      /*ob_size*/
 127         "xx",                   /*tp_name*/
 128         sizeof(xxobject),       /*tp_basicsize*/
 129         0,                      /*tp_itemsize*/
 130         /* methods */
 131         (destructor)xx_dealloc, /*tp_dealloc*/
 132         0,                      /*tp_print*/
 133         (getattrfunc)xx_getattr, /*tp_getattr*/
 134         (setattrfunc)xx_setattr, /*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 };