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_CLOSURE_N_NOTIFIERS(cl)        ((cl)->meta_marshal + ((cl)->n_guards << 1L) + \
  30                                           (cl)->n_fnotifiers + (cl)->n_inotifiers)
  31 #define G_CCLOSURE_SWAP_DATA(cclosure)   (((GClosure*) (closure))->derivative_flag)
  32 #define G_CALLBACK(f)                    ((GCallback) (f))
  33
  34
  35 /* -- typedefs --- */
  36 typedef struct _GClosure                 GClosure;
  37 typedef struct _GClosureNotifyData       GClosureNotifyData;
  38 typedef void  (*GCallback)              (void);
  39 typedef void  (*GClosureNotify)         (gpointer        data,
  40                                          GClosure       *closure);
  41 typedef void  (*GClosureMarshal)        (GClosure       *closure,
  42                                          GValue         *return_value,
  43                                          guint           n_param_values,
  44                                          const GValue   *param_values,
  45                                          gpointer        invocation_hint,
  46                                          gpointer        marshal_data);
  47 typedef struct _GCClosure                GCClosure;
  48
  49
  50 /* --- structures --- */
  51 struct _GClosureNotifyData
  52 {
  53   gpointer       data;
  54   GClosureNotify notify;
  55 };
  56 struct _GClosure
  57 {
  58   /*< private >*/       guint    ref_count : 15;
  59   /*< private >*/       guint    meta_marshal : 1;
  60   /*< private >*/       guint    n_guards : 1;
  61   /*< private >*/       guint    n_fnotifiers : 2;      /* finalization notifiers */
  62   /*< private >*/       guint    n_inotifiers : 8;      /* invalidation notifiers */
  63   /*< private >*/       guint    in_inotify : 1;
  64   /*< private >*/       guint    floating : 1;
  65   /*< protected >*/     guint    derivative_flag : 1;
  66   /*< puplic >*/        guint    in_marshal : 1;
  67   /*< public >*/        guint    is_invalid : 1;
  68
  69   /*< private >*/       void   (*marshal)  (GClosure       *closure,
  70                                             GValue /*out*/ *return_value,
  71                                             guint           n_param_values,
  72                                             const GValue   *param_values,
  73                                             gpointer        invocation_hint,
  74                                             gpointer        marshal_data);
  75   /*< protected >*/     gpointer data;
  76
  77   /*< private >*/       GClosureNotifyData *notifiers;
  78
  79   /* invariants/constrains:
  80    * - ->marshal and ->data are _invalid_ as soon as ->is_invalid==TRUE
  81    * - invocation of all inotifiers occours prior to fnotifiers
  82    * - order of inotifiers is random
  83    *   inotifiers may _not_ free/invalidate parameter values (e.g. ->data)
  84    * - order of fnotifiers is random
  85    * - each notifier may only be removed before or during its invocation
  86    * - reference counting may only happen prior to fnotify invocation
  87    *   (in that sense, fnotifiers are really finalization handlers)
  88    */
  89 };
  90 /* closure for C function calls, callback() is the user function
  91  */
  92 struct _GCClosure
  93 {
  94   GClosure      closure;
  95   gpointer      callback;
  96 };
  97
  98
  99 /* --- prototypes --- */
 100 GClosure* g_cclosure_new                        (GCallback      callback_func,
 101                                                  gpointer       user_data,
 102                                                  GClosureNotify destroy_data);
 103 GClosure* g_cclosure_new_swap                   (GCallback      callback_func,
 104                                                  gpointer       user_data,
 105                                                  GClosureNotify destroy_data);
 106 GClosure* g_signal_type_cclosure_new            (GType          itype,
 107                                                  guint          struct_offset);
 108
 109
 110 /* --- prototypes --- */
 111 GClosure* g_closure_ref                         (GClosure       *closure);
 112 void      g_closure_sink                        (GClosure       *closure);
 113 void      g_closure_unref                       (GClosure       *closure);
 114 /* intimidating */
 115 GClosure* g_closure_new_simple                  (guint           sizeof_closure,
 116                                                  gpointer        data);
 117 void      g_closure_add_finalize_notifier       (GClosure       *closure,
 118                                                  gpointer        notify_data,
 119                                                  GClosureNotify  notify_func);
 120 void      g_closure_remove_finalize_notifier    (GClosure       *closure,
 121                                                  gpointer        notify_data,
 122                                                  GClosureNotify  notify_func);
 123 void      g_closure_add_invalidate_notifier     (GClosure       *closure,
 124                                                  gpointer        notify_data,
 125                                                  GClosureNotify  notify_func);
 126 void      g_closure_remove_invalidate_notifier  (GClosure       *closure,
 127                                                  gpointer        notify_data,
 128                                                  GClosureNotify  notify_func);
 129 void      g_closure_add_marshal_guards          (GClosure       *closure,
 130                                                  gpointer        pre_marshal_data,
 131                                                  GClosureNotify  pre_marshal_notify,
 132                                                  gpointer        post_marshal_data,
 133                                                  GClosureNotify  post_marshal_notify);
 134 void      g_closure_set_marshal                 (GClosure       *closure,
 135                                                  GClosureMarshal marshal);
 136 void      g_closure_set_meta_marshal            (GClosure       *closure,
 137                                                  gpointer        marshal_data,
 138                                                  GClosureMarshal meta_marshal);
 139 void      g_closure_invalidate                  (GClosure       *closure);
 140 void      g_closure_invoke                      (GClosure       *closure,
 141                                                  GValue /*out*/ *return_value,
 142                                                  guint           n_param_values,
 143                                                  const GValue   *param_values,
 144                                                  gpointer        invocation_hint);
 145
 146 /* FIXME:
 147    OK:  data_object::destroy            -> closure_invalidate();
 148    MIS: closure_invalidate()            -> disconnect(closure);
 149    MIS: disconnect(closure)             -> (unlink) closure_unref();
 150    OK:  closure_finalize()              -> g_free (data_string);
 151
 152    random remarks:
 153    - need marshaller repo with decent aliasing to base types
 154    - provide marshaller collection, virtually covering anything out there
 155 */
 156
 157 G_END_DECLS
 158
 159 #endif /* __G_CLOSURE_H__ */