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 #if !defined (__GLIB_GOBJECT_H_INSIDE__) && !defined (GOBJECT_COMPILATION)
  20 #error "Only <glib-object.h> can be included directly."
  21 #endif
  22
  23 #ifndef __G_CLOSURE_H__
  24 #define __G_CLOSURE_H__
  25
  26 #include        <gobject/gtype.h>
  27
  28 G_BEGIN_DECLS
  29
  30 /* --- defines --- */
  31 #define G_CLOSURE_NEEDS_MARSHAL(closure) (((GClosure*) (closure))->marshal == NULL)
  32 #define G_CLOSURE_N_NOTIFIERS(cl)        ((cl)->meta_marshal + ((cl)->n_guards << 1L) + \
  33                                           (cl)->n_fnotifiers + (cl)->n_inotifiers)
  34 #define G_CCLOSURE_SWAP_DATA(cclosure)   (((GClosure*) (closure))->derivative_flag)
  35 #define G_CALLBACK(f)                    ((GCallback) (f))
  36
  37
  38 /* -- typedefs --- */
  39 typedef struct _GClosure                 GClosure;
  40 typedef struct _GClosureNotifyData       GClosureNotifyData;
  41 typedef void  (*GCallback)              (void);
  42 typedef void  (*GClosureNotify)         (gpointer        data,
  43                                          GClosure       *closure);
  44 typedef void  (*GClosureMarshal)        (GClosure       *closure,
  45                                          GValue         *return_value,
  46                                          guint           n_param_values,
  47                                          const GValue   *param_values,
  48                                          gpointer        invocation_hint,
  49                                          gpointer        marshal_data);
  50 typedef struct _GCClosure                GCClosure;
  51
  52
  53 /* --- structures --- */
  54 struct _GClosureNotifyData
  55 {
  56   gpointer       data;
  57   GClosureNotify notify;
  58 };
  59 struct _GClosure
  60 {
  61   /*< private >*/       guint    ref_count : 15;
  62   /*< private >*/       guint    meta_marshal : 1;
  63   /*< private >*/       guint    n_guards : 1;
  64   /*< private >*/       guint    n_fnotifiers : 2;      /* finalization notifiers */
  65   /*< private >*/       guint    n_inotifiers : 8;      /* invalidation notifiers */
  66   /*< private >*/       guint    in_inotify : 1;
  67   /*< private >*/       guint    floating : 1;
  68   /*< protected >*/     guint    derivative_flag : 1;
  69   /*< public >*/        guint    in_marshal : 1;
  70   /*< public >*/        guint    is_invalid : 1;
  71
  72   /*< private >*/       void   (*marshal)  (GClosure       *closure,
  73                                             GValue /*out*/ *return_value,
  74                                             guint           n_param_values,
  75                                             const GValue   *param_values,
  76                                             gpointer        invocation_hint,
  77                                             gpointer        marshal_data);
  78   /*< protected >*/     gpointer data;
  79
  80   /*< private >*/       GClosureNotifyData *notifiers;
  81
  82   /* invariants/constrains:
  83    * - ->marshal and ->data are _invalid_ as soon as ->is_invalid==TRUE
  84    * - invocation of all inotifiers occours prior to fnotifiers
  85    * - order of inotifiers is random
  86    *   inotifiers may _not_ free/invalidate parameter values (e.g. ->data)
  87    * - order of fnotifiers is random
  88    * - each notifier may only be removed before or during its invocation
  89    * - reference counting may only happen prior to fnotify invocation
  90    *   (in that sense, fnotifiers are really finalization handlers)
  91    */
  92 };
  93 /* closure for C function calls, callback() is the user function
  94  */
  95 struct _GCClosure
  96 {
  97   GClosure      closure;
  98   gpointer      callback;
  99 };
 100
 101
 102 /* --- prototypes --- */
 103 GClosure* g_cclosure_new                        (GCallback      callback_func,
 104                                                  gpointer       user_data,
 105                                                  GClosureNotify destroy_data);
 106 GClosure* g_cclosure_new_swap                   (GCallback      callback_func,
 107                                                  gpointer       user_data,
 108                                                  GClosureNotify destroy_data);
 109 GClosure* g_signal_type_cclosure_new            (GType          itype,
 110                                                  guint          struct_offset);
 111
 112
 113 /* --- prototypes --- */
 114 GClosure* g_closure_ref                         (GClosure       *closure);
 115 void      g_closure_sink                        (GClosure       *closure);
 116 void      g_closure_unref                       (GClosure       *closure);
 117 /* intimidating */
 118 GClosure* g_closure_new_simple                  (guint           sizeof_closure,
 119                                                  gpointer        data);
 120 void      g_closure_add_finalize_notifier       (GClosure       *closure,
 121                                                  gpointer        notify_data,
 122                                                  GClosureNotify  notify_func);
 123 void      g_closure_remove_finalize_notifier    (GClosure       *closure,
 124                                                  gpointer        notify_data,
 125                                                  GClosureNotify  notify_func);
 126 void      g_closure_add_invalidate_notifier     (GClosure       *closure,
 127                                                  gpointer        notify_data,
 128                                                  GClosureNotify  notify_func);
 129 void      g_closure_remove_invalidate_notifier  (GClosure       *closure,
 130                                                  gpointer        notify_data,
 131                                                  GClosureNotify  notify_func);
 132 void      g_closure_add_marshal_guards          (GClosure       *closure,
 133                                                  gpointer        pre_marshal_data,
 134                                                  GClosureNotify  pre_marshal_notify,
 135                                                  gpointer        post_marshal_data,
 136                                                  GClosureNotify  post_marshal_notify);
 137 void      g_closure_set_marshal                 (GClosure       *closure,
 138                                                  GClosureMarshal marshal);
 139 void      g_closure_set_meta_marshal            (GClosure       *closure,
 140                                                  gpointer        marshal_data,
 141                                                  GClosureMarshal meta_marshal);
 142 void      g_closure_invalidate                  (GClosure       *closure);
 143 void      g_closure_invoke                      (GClosure       *closure,
 144                                                  GValue /*out*/ *return_value,
 145                                                  guint           n_param_values,
 146                                                  const GValue   *param_values,
 147                                                  gpointer        invocation_hint);
 148
 149 /* FIXME:
 150    OK:  data_object::destroy            -> closure_invalidate();
 151    MIS: closure_invalidate()            -> disconnect(closure);
 152    MIS: disconnect(closure)             -> (unlink) closure_unref();
 153    OK:  closure_finalize()              -> g_free (data_string);
 154
 155    random remarks:
 156    - need marshaller repo with decent aliasing to base types
 157    - provide marshaller collection, virtually covering anything out there
 158 */
 159
 160 G_END_DECLS
 161
 162 #endif /* __G_CLOSURE_H__ */