gobject/gclosure.h

   1 /* GObject - GLib Type, Object, Parameter and Signal Library
   2  * Copyright (C) 2000-2001 Red Hat, Inc.
   3  * Copyright (C) 2005 Imendio AB
   4  *
   5  * This library is free software; you can redistribute it and/or
   6  * modify it under the terms of the GNU Lesser General Public
   7  * License as published by the Free Software Foundation; either
   8  * version 2 of the License, or (at your option) any later version.
   9  *
  10  * This library is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  13  * Lesser General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU Lesser General
  16  * Public License along with this library; if not, write to the
  17  * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
  18  * Boston, MA 02111-1307, USA.
  19  */
  20 #if !defined (__GLIB_GOBJECT_H_INSIDE__) && !defined (GOBJECT_COMPILATION)
  21 #error "Only <glib-object.h> can be included directly."
  22 #endif
  23
  24 #ifndef __G_CLOSURE_H__
  25 #define __G_CLOSURE_H__
  26
  27 #include        <gobject/gtype.h>
  28
  29 G_BEGIN_DECLS
  30
  31 /* --- defines --- */
  32 #define G_CLOSURE_NEEDS_MARSHAL(closure) (((GClosure*) (closure))->marshal == NULL)
  33 #define G_CLOSURE_N_NOTIFIERS(cl)        ((cl)->meta_marshal + ((cl)->n_guards << 1L) + \
  34                                           (cl)->n_fnotifiers + (cl)->n_inotifiers)
  35 #define G_CCLOSURE_SWAP_DATA(cclosure)   (((GClosure*) (closure))->derivative_flag)
  36 #define G_CALLBACK(f)                    ((GCallback) (f))
  37
  38
  39 /* -- typedefs --- */
  40 typedef struct _GClosure                 GClosure;
  41 typedef struct _GClosureNotifyData       GClosureNotifyData;
  42 typedef void  (*GCallback)              (void);
  43 typedef void  (*GClosureNotify)         (gpointer        data,
  44                                          GClosure       *closure);
  45 typedef void  (*GClosureMarshal)        (GClosure       *closure,
  46                                          GValue         *return_value,
  47                                          guint           n_param_values,
  48                                          const GValue   *param_values,
  49                                          gpointer        invocation_hint,
  50                                          gpointer        marshal_data);
  51 typedef struct _GCClosure                GCClosure;
  52
  53
  54 /* --- structures --- */
  55 struct _GClosureNotifyData
  56 {
  57   gpointer       data;
  58   GClosureNotify notify;
  59 };
  60 struct _GClosure
  61 {
  62   /*< private >*/
  63   volatile              guint    ref_count : 15;
  64   volatile              guint    meta_marshal : 1;
  65   volatile              guint    n_guards : 1;
  66   volatile              guint    n_fnotifiers : 2;      /* finalization notifiers */
  67   volatile              guint    n_inotifiers : 8;      /* invalidation notifiers */
  68   volatile              guint    in_inotify : 1;
  69   volatile              guint    floating : 1;
  70   /*< protected >*/
  71   volatile              guint    derivative_flag : 1;
  72   /*< public >*/
  73   volatile              guint    in_marshal : 1;
  74   volatile              guint    is_invalid : 1;
  75
  76   /*< private >*/       void   (*marshal)  (GClosure       *closure,
  77                                             GValue /*out*/ *return_value,
  78                                             guint           n_param_values,
  79                                             const GValue   *param_values,
  80                                             gpointer        invocation_hint,
  81                                             gpointer        marshal_data);
  82   /*< protected >*/     gpointer data;
  83
  84   /*< private >*/       GClosureNotifyData *notifiers;
  85
  86   /* invariants/constrains:
  87    * - ->marshal and ->data are _invalid_ as soon as ->is_invalid==TRUE
  88    * - invocation of all inotifiers occours prior to fnotifiers
  89    * - order of inotifiers is random
  90    *   inotifiers may _not_ free/invalidate parameter values (e.g. ->data)
  91    * - order of fnotifiers is random
  92    * - each notifier may only be removed before or during its invocation
  93    * - reference counting may only happen prior to fnotify invocation
  94    *   (in that sense, fnotifiers are really finalization handlers)
  95    */
  96 };
  97 /* closure for C function calls, callback() is the user function
  98  */
  99 struct _GCClosure
 100 {
 101   GClosure      closure;
 102   gpointer      callback;
 103 };
 104
 105
 106 /* --- prototypes --- */
 107 GClosure* g_cclosure_new                        (GCallback      callback_func,
 108                                                  gpointer       user_data,
 109                                                  GClosureNotify destroy_data);
 110 GClosure* g_cclosure_new_swap                   (GCallback      callback_func,
 111                                                  gpointer       user_data,
 112                                                  GClosureNotify destroy_data);
 113 GClosure* g_signal_type_cclosure_new            (GType          itype,
 114                                                  guint          struct_offset);
 115
 116
 117 /* --- prototypes --- */
 118 GClosure* g_closure_ref                         (GClosure       *closure);
 119 void      g_closure_sink                        (GClosure       *closure);
 120 void      g_closure_unref                       (GClosure       *closure);
 121 /* intimidating */
 122 GClosure* g_closure_new_simple                  (guint           sizeof_closure,
 123                                                  gpointer        data);
 124 void      g_closure_add_finalize_notifier       (GClosure       *closure,
 125                                                  gpointer        notify_data,
 126                                                  GClosureNotify  notify_func);
 127 void      g_closure_remove_finalize_notifier    (GClosure       *closure,
 128                                                  gpointer        notify_data,
 129                                                  GClosureNotify  notify_func);
 130 void      g_closure_add_invalidate_notifier     (GClosure       *closure,
 131                                                  gpointer        notify_data,
 132                                                  GClosureNotify  notify_func);
 133 void      g_closure_remove_invalidate_notifier  (GClosure       *closure,
 134                                                  gpointer        notify_data,
 135                                                  GClosureNotify  notify_func);
 136 void      g_closure_add_marshal_guards          (GClosure       *closure,
 137                                                  gpointer        pre_marshal_data,
 138                                                  GClosureNotify  pre_marshal_notify,
 139                                                  gpointer        post_marshal_data,
 140                                                  GClosureNotify  post_marshal_notify);
 141 void      g_closure_set_marshal                 (GClosure       *closure,
 142                                                  GClosureMarshal marshal);
 143 void      g_closure_set_meta_marshal            (GClosure       *closure,
 144                                                  gpointer        marshal_data,
 145                                                  GClosureMarshal meta_marshal);
 146 void      g_closure_invalidate                  (GClosure       *closure);
 147 void      g_closure_invoke                      (GClosure       *closure,
 148                                                  GValue /*out*/ *return_value,
 149                                                  guint           n_param_values,
 150                                                  const GValue   *param_values,
 151                                                  gpointer        invocation_hint);
 152
 153 /* FIXME:
 154    OK:  data_object::destroy            -> closure_invalidate();
 155    MIS: closure_invalidate()            -> disconnect(closure);
 156    MIS: disconnect(closure)             -> (unlink) closure_unref();
 157    OK:  closure_finalize()              -> g_free (data_string);
 158
 159    random remarks:
 160    - need marshaller repo with decent aliasing to base types
 161    - provide marshaller collection, virtually covering anything out there
 162 */
 163
 164 G_END_DECLS
 165
 166 #endif /* __G_CLOSURE_H__ */