libguile/objprop.c

   1 /*      Copyright (C) 1995,1996 Free Software Foundation, Inc.
   2  *
   3  * This program is free software; you can redistribute it and/or modify
   4  * it under the terms of the GNU General Public License as published by
   5  * the Free Software Foundation; either version 2, or (at your option)
   6  * any later version.
   7  *
   8  * This program is distributed in the hope that it will be useful,
   9  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  10  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  11  * GNU General Public License for more details.
  12  *
  13  * You should have received a copy of the GNU General Public License
  14  * along with this software; see the file COPYING.  If not, write to
  15  * the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA.
  16  *
  17  * As a special exception, the Free Software Foundation gives permission
  18  * for additional uses of the text contained in its release of GUILE.
  19  *
  20  * The exception is that, if you link the GUILE library with other files
  21  * to produce an executable, this does not by itself cause the
  22  * resulting executable to be covered by the GNU General Public License.
  23  * Your use of that executable is in no way restricted on account of
  24  * linking the GUILE library code into it.
  25  *
  26  * This exception does not however invalidate any other reasons why
  27  * the executable file might be covered by the GNU General Public License.
  28  *
  29  * This exception applies only to the code released by the
  30  * Free Software Foundation under the name GUILE.  If you copy
  31  * code from other Free Software Foundation releases into a copy of
  32  * GUILE, as the General Public License permits, the exception does
  33  * not apply to the code that you add in this way.  To avoid misleading
  34  * anyone as to the status of such modified files, you must delete
  35  * this exception notice from them.
  36  *
  37  * If you write modifications of your own for GUILE, it is your choice
  38  * whether to permit this exception to apply to your modifications.
  39  * If you do not wish that, delete this exception notice.
  40  */
  41 \f
  42
  43 #include <stdio.h>
  44 #include "_scm.h"
  45 #include "hashtab.h"
  46 #include "alist.h"
  47 #include "weaks.h"
  48
  49 #include "objprop.h"
  50 \f
  51
  52 /* {Object Properties}
  53  */
  54
  55 SCM_PROC(s_object_properties, "object-properties", 1, 0, 0, scm_object_properties);
  56
  57 SCM
  58 scm_object_properties (obj)
  59      SCM obj;
  60 {
  61   return scm_hashq_ref (scm_object_whash, obj, SCM_EOL);
  62 }
  63
  64
  65 SCM_PROC(s_set_object_properties_x, "set-object-properties!", 2, 0, 0, scm_set_object_properties_x);
  66
  67 SCM
  68 scm_set_object_properties_x (obj, plist)
  69      SCM obj;
  70      SCM plist;
  71 {
  72   SCM handle = scm_hashq_create_handle_x (scm_object_whash, obj, plist);
  73   SCM_SETCDR (handle, plist);
  74   return plist;
  75 }
  76
  77 SCM_PROC(s_object_property, "object-property", 2, 0, 0, scm_object_property);
  78
  79 SCM
  80 scm_object_property (obj, key)
  81      SCM obj;
  82      SCM key;
  83 {
  84   SCM assoc;
  85   assoc = scm_assq (key, SCM_CDR (scm_object_properties (obj)));
  86   return (SCM_NIMP (assoc) ? SCM_CDR (assoc) : SCM_BOOL_F);
  87 }
  88
  89 SCM_PROC(s_set_object_property_x, "set-object-property!", 3, 0, 0, scm_set_object_property_x);
  90
  91 SCM
  92 scm_set_object_property_x (obj, key, val)
  93      SCM obj;
  94      SCM key;
  95      SCM val;
  96 {
  97   SCM h;
  98   SCM assoc;
  99   h = scm_hashq_create_handle_x (scm_object_whash, obj, SCM_EOL);
 100   SCM_DEFER_INTS;
 101   assoc = scm_assoc (key, SCM_CDR (h));
 102   if (SCM_NIMP (assoc))
 103     SCM_SETCDR (assoc, val);
 104   else
 105     {
 106       assoc = scm_acons (key, val, SCM_CDR (h));
 107       SCM_SETCDR (h, assoc);
 108     }
 109   SCM_ALLOW_INTS;
 110   return val;
 111 }
 112
 113
 114 void
 115 scm_init_objprop ()
 116 {
 117   scm_object_whash = scm_make_weak_key_hash_table (SCM_MAKINUM (511));
 118 #include "objprop.x"
 119 }
 120