gobject/gclosure.h

   1 /* GObject - GLib Type, Object, Parameter and Signal Library
   2  * Copyright (C) 2000-2001 Red Hat, Inc.
   3  *
   4  * This library is free software; you can redistribute it and/or
   5  * modify it under the terms of the GNU Lesser General Public
   6  * License as published by the Free Software Foundation; either
   7  * version 2 of the License, or (at your option) any later version.
   8  *
   9  * This library is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12  * Lesser General Public License for more details.
  13  *
  14  * You should have received a copy of the GNU Lesser General
  15  * Public License along with this library; if not, write to the
  16  * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  17  * Boston, MA 02111-1307, USA.
  18  */
  19 #ifndef __G_CLOSURE_H__
  20 #define __G_CLOSURE_H__
  21
  22
  23 #include        <gobject/gtype.h>
  24
  25 G_BEGIN_DECLS
  26
  27 /* --- defines --- */
  28 #define G_CLOSURE_NEEDS_MARSHAL(closure) (((GClosure*) (closure))->marshal == NULL)
  29 #define G_CCLOSURE_SWAP_DATA(cclosure)   (((GClosure*) (closure))->derivative_flag)
  30 #define G_CALLBACK(f)                    ((GCallback) (f))
  31
  32
  33 /* -- typedefs --- */
  34 typedef struct _GClosure                 GClosure;
  35 typedef struct _GClosureNotifyData       GClosureNotifyData;
  36 typedef gpointer                         GCallback;
  37 typedef void  (*GClosureNotify)         (gpointer        data,
  38                                          GClosure       *closure);
  39 typedef void  (*GClosureMarshal)        (GClosure       *closure,
  40                                          GValue         *return_value,
  41                                          guint           n_param_values,
  42                                          const GValue   *param_values,
  43                                          gpointer        invocation_hint,
  44                                          gpointer        marshal_data);
  45 typedef struct _GCClosure                GCClosure;
  46
  47
  48 /* --- structures --- */
  49 struct _GClosureNotifyData
  50 {
  51   gpointer       data;
  52   GClosureNotify notify;
  53 };
  54 struct _GClosure
  55 {
  56   /*< private >*/       guint    ref_count : 15;
  57   /*< private >*/       guint    meta_marshal : 1;
  58   /*< private >*/       guint    n_guards : 1;
  59   /*< private >*/       guint    n_fnotifiers : 2;      /* finalization notifiers */
  60   /*< private >*/       guint    n_inotifiers : 8;      /* invalidation notifiers */
  61   /*< private >*/       guint    in_inotify : 1;
  62   /*< private >*/       guint    floating : 1;
  63   /*< protected >*/     guint    derivative_flag : 1;
  64   /*< puplic >*/        guint    in_marshal : 1;
  65   /*< public >*/        guint    is_invalid : 1;
  66
  67   /*< private >*/       void   (*marshal)  (GClosure       *closure,
  68                                             GValue /*out*/ *return_value,
  69                                             guint           n_param_values,
  70                                             const GValue   *param_values,
  71                                             gpointer        invocation_hint,
  72                                             gpointer        marshal_data);
  73   /*< protected >*/     gpointer data;
  74
  75   /*< private >*/       GClosureNotifyData *notifiers;
  76
  77   /* invariants/constrains:
  78    * - ->marshal and ->data are _invalid_ as soon as ->is_invalid==TRUE
  79    * - invocation of all inotifiers occours prior to fnotifiers
  80    * - order of inotifiers is random
  81    *   inotifiers may _not_ free/invalidate parameter values (e.g. ->data)
  82    * - order of fnotifiers is random
  83    * - each notifier may only be removed before or during its invocation
  84    * - reference counting may only happen prior to fnotify invocation
  85    *   (in that sense, fnotifiers are really finalization handlers)
  86    */
  87 };
  88 /* closure for C function calls, callback() is the user function
  89  */
  90 struct _GCClosure
  91 {
  92   GClosure      closure;
  93   gpointer      callback;
  94 };
  95
  96
  97 /* --- prototypes --- */
  98 GClosure*       g_cclosure_new                  (GCallback      callback_func,
  99                                                  gpointer       user_data,
 100                                                  GClosureNotify destroy_data);
 101 GClosure*       g_cclosure_new_swap             (GCallback      callback_func,
 102                                                  gpointer       user_data,
 103                                                  GClosureNotify destroy_data);
 104 GClosure*       g_signal_type_cclosure_new      (GType          itype,
 105                                                  guint          struct_offset);
 106
 107
 108 /* --- prototypes --- */
 109 GClosure*       g_closure_ref                   (GClosure       *closure);
 110 void            g_closure_sink                  (GClosure       *closure);
 111 void            g_closure_unref                 (GClosure       *closure);
 112 /* intimidating */
 113 GClosure*       g_closure_new_simple            (guint           sizeof_closure,
 114                                                  gpointer        data);
 115 void            g_closure_add_fnotify           (GClosure       *closure,
 116                                                  gpointer        notify_data,
 117                                                  GClosureNotify  notify_func);
 118 void            g_closure_remove_fnotify        (GClosure       *closure,
 119                                                  gpointer        notify_data,
 120                                                  GClosureNotify  notify_func);
 121 void            g_closure_add_inotify           (GClosure       *closure,
 122                                                  gpointer        notify_data,
 123                                                  GClosureNotify  notify_func);
 124 void            g_closure_remove_inotify        (GClosure       *closure,
 125                                                  gpointer        notify_data,
 126                                                  GClosureNotify  notify_func);
 127 void            g_closure_add_marshal_guards    (GClosure       *closure,
 128                                                  gpointer        pre_marshal_data,
 129                                                  GClosureNotify  pre_marshal_notify,
 130                                                  gpointer        post_marshal_data,
 131                                                  GClosureNotify  post_marshal_notify);
 132 void            g_closure_set_marshal           (GClosure       *closure,
 133                                                  GClosureMarshal marshal);
 134 void            g_closure_set_meta_marshal      (GClosure       *closure,
 135                                                  gpointer        marshal_data,
 136                                                  GClosureMarshal meta_marshal);
 137 void            g_closure_invalidate            (GClosure       *closure);
 138 void            g_closure_invoke                (GClosure       *closure,
 139                                                  GValue /*out*/ *return_value,
 140                                                  guint           n_param_values,
 141                                                  const GValue   *param_values,
 142                                                  gpointer        invocation_hint);
 143
 144
 145 /* FIXME:
 146    OK:  data_object::destroy            -> closure_invalidate();
 147    MIS: closure_invalidate()            -> disconnect(closure);
 148    MIS: disconnect(closure)             -> (unlink) closure_unref();
 149    OK:  closure_finalize()              -> g_free (data_string);
 150
 151    random remarks:
 152    - need marshaller repo with decent aliasing to base types
 153    - provide marshaller collection, virtually covering anything out there
 154 */
 155
 156 G_END_DECLS
 157
 158 #endif /* __G_CLOSURE_H__ */