hook gvariant vectors up to kdbus
[platform/upstream/glib.git] / gobject / gsignal.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, see <http://www.gnu.org/licenses/>.
16  */
17 #ifndef __G_SIGNAL_H__
18 #define __G_SIGNAL_H__
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 #include        <gobject/gclosure.h>
25 #include        <gobject/gvalue.h>
26 #include        <gobject/gparam.h>
27 #include        <gobject/gmarshal.h>
28
29 G_BEGIN_DECLS
30
31 /* --- typedefs --- */
32 typedef struct _GSignalQuery             GSignalQuery;
33 typedef struct _GSignalInvocationHint    GSignalInvocationHint;
34 /**
35  * GSignalCMarshaller:
36  * 
37  * This is the signature of marshaller functions, required to marshall
38  * arrays of parameter values to signal emissions into C language callback
39  * invocations. It is merely an alias to #GClosureMarshal since the #GClosure
40  * mechanism takes over responsibility of actual function invocation for the
41  * signal system.
42  */
43 typedef GClosureMarshal                  GSignalCMarshaller;
44 /**
45  * GSignalCVaMarshaller:
46  * 
47  * This is the signature of va_list marshaller functions, an optional
48  * marshaller that can be used in some situations to avoid
49  * marshalling the signal argument into GValues.
50  */
51 typedef GVaClosureMarshal                GSignalCVaMarshaller;
52 /**
53  * GSignalEmissionHook:
54  * @ihint: Signal invocation hint, see #GSignalInvocationHint.
55  * @n_param_values: the number of parameters to the function, including
56  *  the instance on which the signal was emitted.
57  * @param_values: (array length=n_param_values): the instance on which
58  *  the signal was emitted, followed by the parameters of the emission.
59  * @data: user data associated with the hook.
60  * 
61  * A simple function pointer to get invoked when the signal is emitted. This 
62  * allows you to tie a hook to the signal type, so that it will trap all 
63  * emissions of that signal, from any object.
64  * 
65  * You may not attach these to signals created with the #G_SIGNAL_NO_HOOKS flag.
66  * 
67  * Returns: whether it wants to stay connected. If it returns %FALSE, the signal 
68  *  hook is disconnected (and destroyed).
69  */
70 typedef gboolean (*GSignalEmissionHook) (GSignalInvocationHint *ihint,
71                                          guint                  n_param_values,
72                                          const GValue          *param_values,
73                                          gpointer               data);
74 /**
75  * GSignalAccumulator:
76  * @ihint: Signal invocation hint, see #GSignalInvocationHint.
77  * @return_accu: Accumulator to collect callback return values in, this
78  *  is the return value of the current signal emission.
79  * @handler_return: A #GValue holding the return value of the signal handler.
80  * @data: Callback data that was specified when creating the signal.
81  * 
82  * The signal accumulator is a special callback function that can be used
83  * to collect return values of the various callbacks that are called
84  * during a signal emission. The signal accumulator is specified at signal
85  * creation time, if it is left %NULL, no accumulation of callback return
86  * values is performed. The return value of signal emissions is then the
87  * value returned by the last callback.
88  * 
89  * Returns: The accumulator function returns whether the signal emission
90  *  should be aborted. Returning %FALSE means to abort the
91  *  current emission and %TRUE is returned for continuation.
92  */
93 typedef gboolean (*GSignalAccumulator)  (GSignalInvocationHint *ihint,
94                                          GValue                *return_accu,
95                                          const GValue          *handler_return,
96                                          gpointer               data);
97
98
99 /* --- run, match and connect types --- */
100 /**
101  * GSignalFlags:
102  * @G_SIGNAL_RUN_FIRST: Invoke the object method handler in the first emission stage.
103  * @G_SIGNAL_RUN_LAST: Invoke the object method handler in the third emission stage.
104  * @G_SIGNAL_RUN_CLEANUP: Invoke the object method handler in the last emission stage.
105  * @G_SIGNAL_NO_RECURSE: Signals being emitted for an object while currently being in
106  *  emission for this very object will not be emitted recursively,
107  *  but instead cause the first emission to be restarted.
108  * @G_SIGNAL_DETAILED: This signal supports "::detail" appendices to the signal name
109  *  upon handler connections and emissions.
110  * @G_SIGNAL_ACTION: Action signals are signals that may freely be emitted on alive
111  *  objects from user code via g_signal_emit() and friends, without
112  *  the need of being embedded into extra code that performs pre or
113  *  post emission adjustments on the object. They can also be thought
114  *  of as object methods which can be called generically by 
115  *  third-party code.
116  * @G_SIGNAL_NO_HOOKS: No emissions hooks are supported for this signal.
117  * @G_SIGNAL_MUST_COLLECT: Varargs signal emission will always collect the
118  *   arguments, even if there are no signal handlers connected.  Since 2.30.
119  * @G_SIGNAL_DEPRECATED: The signal is deprecated and will be removed
120  *   in a future version. A warning will be generated if it is connected while
121  *   running with G_ENABLE_DIAGNOSTIC=1.  Since 2.32.
122  * 
123  * The signal flags are used to specify a signal's behaviour, the overall
124  * signal description outlines how especially the RUN flags control the
125  * stages of a signal emission.
126  */
127 typedef enum
128 {
129   G_SIGNAL_RUN_FIRST    = 1 << 0,
130   G_SIGNAL_RUN_LAST     = 1 << 1,
131   G_SIGNAL_RUN_CLEANUP  = 1 << 2,
132   G_SIGNAL_NO_RECURSE   = 1 << 3,
133   G_SIGNAL_DETAILED     = 1 << 4,
134   G_SIGNAL_ACTION       = 1 << 5,
135   G_SIGNAL_NO_HOOKS     = 1 << 6,
136   G_SIGNAL_MUST_COLLECT = 1 << 7,
137   G_SIGNAL_DEPRECATED   = 1 << 8
138 } GSignalFlags;
139 /**
140  * G_SIGNAL_FLAGS_MASK:
141  * 
142  * A mask for all #GSignalFlags bits.
143  */
144 #define G_SIGNAL_FLAGS_MASK  0x1ff
145 /**
146  * GConnectFlags:
147  * @G_CONNECT_AFTER: whether the handler should be called before or after the 
148  *  default handler of the signal.
149  * @G_CONNECT_SWAPPED: whether the instance and data should be swapped when
150  *  calling the handler; see g_signal_connect_swapped() for an example.
151  * 
152  * The connection flags are used to specify the behaviour of a signal's 
153  * connection.
154  */
155 typedef enum
156 {
157   G_CONNECT_AFTER       = 1 << 0,
158   G_CONNECT_SWAPPED     = 1 << 1
159 } GConnectFlags;
160 /**
161  * GSignalMatchType:
162  * @G_SIGNAL_MATCH_ID: The signal id must be equal.
163  * @G_SIGNAL_MATCH_DETAIL: The signal detail be equal.
164  * @G_SIGNAL_MATCH_CLOSURE: The closure must be the same.
165  * @G_SIGNAL_MATCH_FUNC: The C closure callback must be the same.
166  * @G_SIGNAL_MATCH_DATA: The closure data must be the same.
167  * @G_SIGNAL_MATCH_UNBLOCKED: Only unblocked signals may matched.
168  * 
169  * The match types specify what g_signal_handlers_block_matched(),
170  * g_signal_handlers_unblock_matched() and g_signal_handlers_disconnect_matched()
171  * match signals by.
172  */
173 typedef enum
174 {
175   G_SIGNAL_MATCH_ID        = 1 << 0,
176   G_SIGNAL_MATCH_DETAIL    = 1 << 1,
177   G_SIGNAL_MATCH_CLOSURE   = 1 << 2,
178   G_SIGNAL_MATCH_FUNC      = 1 << 3,
179   G_SIGNAL_MATCH_DATA      = 1 << 4,
180   G_SIGNAL_MATCH_UNBLOCKED = 1 << 5
181 } GSignalMatchType;
182 /**
183  * G_SIGNAL_MATCH_MASK:
184  * 
185  * A mask for all #GSignalMatchType bits.
186  */
187 #define G_SIGNAL_MATCH_MASK  0x3f
188 /**
189  * G_SIGNAL_TYPE_STATIC_SCOPE:
190  * 
191  * This macro flags signal argument types for which the signal system may 
192  * assume that instances thereof remain persistent across all signal emissions
193  * they are used in. This is only useful for non ref-counted, value-copy types.
194  * 
195  * To flag a signal argument in this way, add `| G_SIGNAL_TYPE_STATIC_SCOPE`
196  * to the corresponding argument of g_signal_new().
197  * |[
198  * g_signal_new ("size_request",
199  *   G_TYPE_FROM_CLASS (gobject_class),
200  *       G_SIGNAL_RUN_FIRST,
201  *       G_STRUCT_OFFSET (GtkWidgetClass, size_request),
202  *       NULL, NULL,
203  *       _gtk_marshal_VOID__BOXED,
204  *       G_TYPE_NONE, 1,
205  *       GTK_TYPE_REQUISITION | G_SIGNAL_TYPE_STATIC_SCOPE);
206  * ]|
207  */
208 #define G_SIGNAL_TYPE_STATIC_SCOPE (G_TYPE_FLAG_RESERVED_ID_BIT)
209
210
211 /* --- signal information --- */
212 /**
213  * GSignalInvocationHint:
214  * @signal_id: The signal id of the signal invoking the callback
215  * @detail: The detail passed on for this emission
216  * @run_type: The stage the signal emission is currently in, this
217  *  field will contain one of %G_SIGNAL_RUN_FIRST,
218  *  %G_SIGNAL_RUN_LAST or %G_SIGNAL_RUN_CLEANUP.
219  * 
220  * The #GSignalInvocationHint structure is used to pass on additional information
221  * to callbacks during a signal emission.
222  */
223 struct _GSignalInvocationHint
224 {
225   guint         signal_id;
226   GQuark        detail;
227   GSignalFlags  run_type;
228 };
229 /**
230  * GSignalQuery:
231  * @signal_id: The signal id of the signal being queried, or 0 if the
232  *  signal to be queried was unknown.
233  * @signal_name: The signal name.
234  * @itype: The interface/instance type that this signal can be emitted for.
235  * @signal_flags: The signal flags as passed in to g_signal_new().
236  * @return_type: The return type for user callbacks.
237  * @n_params: The number of parameters that user callbacks take.
238  * @param_types: (array length=n_params): The individual parameter types for
239  *  user callbacks, note that the effective callback signature is:
240  *  |[<!-- language="C" -->
241  *  @return_type callback (#gpointer     data1,
242  *  [param_types param_names,]
243  *  gpointer     data2);
244  *  ]|
245  * 
246  * A structure holding in-depth information for a specific signal. It is
247  * filled in by the g_signal_query() function.
248  */
249 struct _GSignalQuery
250 {
251   guint         signal_id;
252   const gchar  *signal_name;
253   GType         itype;
254   GSignalFlags  signal_flags;
255   GType         return_type; /* mangled with G_SIGNAL_TYPE_STATIC_SCOPE flag */
256   guint         n_params;
257   const GType  *param_types; /* mangled with G_SIGNAL_TYPE_STATIC_SCOPE flag */
258 };
259
260
261 /* --- signals --- */
262 GLIB_AVAILABLE_IN_ALL
263 guint                 g_signal_newv         (const gchar        *signal_name,
264                                              GType               itype,
265                                              GSignalFlags        signal_flags,
266                                              GClosure           *class_closure,
267                                              GSignalAccumulator  accumulator,
268                                              gpointer            accu_data,
269                                              GSignalCMarshaller  c_marshaller,
270                                              GType               return_type,
271                                              guint               n_params,
272                                              GType              *param_types);
273 GLIB_AVAILABLE_IN_ALL
274 guint                 g_signal_new_valist   (const gchar        *signal_name,
275                                              GType               itype,
276                                              GSignalFlags        signal_flags,
277                                              GClosure           *class_closure,
278                                              GSignalAccumulator  accumulator,
279                                              gpointer            accu_data,
280                                              GSignalCMarshaller  c_marshaller,
281                                              GType               return_type,
282                                              guint               n_params,
283                                              va_list             args);
284 GLIB_AVAILABLE_IN_ALL
285 guint                 g_signal_new          (const gchar        *signal_name,
286                                              GType               itype,
287                                              GSignalFlags        signal_flags,
288                                              guint               class_offset,
289                                              GSignalAccumulator  accumulator,
290                                              gpointer            accu_data,
291                                              GSignalCMarshaller  c_marshaller,
292                                              GType               return_type,
293                                              guint               n_params,
294                                              ...);
295 GLIB_AVAILABLE_IN_ALL
296 guint            g_signal_new_class_handler (const gchar        *signal_name,
297                                              GType               itype,
298                                              GSignalFlags        signal_flags,
299                                              GCallback           class_handler,
300                                              GSignalAccumulator  accumulator,
301                                              gpointer            accu_data,
302                                              GSignalCMarshaller  c_marshaller,
303                                              GType               return_type,
304                                              guint               n_params,
305                                              ...);
306 GLIB_AVAILABLE_IN_ALL
307 void             g_signal_set_va_marshaller (guint              signal_id,
308                                              GType              instance_type,
309                                              GSignalCVaMarshaller va_marshaller);
310
311 GLIB_AVAILABLE_IN_ALL
312 void                  g_signal_emitv        (const GValue       *instance_and_params,
313                                              guint               signal_id,
314                                              GQuark              detail,
315                                              GValue             *return_value);
316 GLIB_AVAILABLE_IN_ALL
317 void                  g_signal_emit_valist  (gpointer            instance,
318                                              guint               signal_id,
319                                              GQuark              detail,
320                                              va_list             var_args);
321 GLIB_AVAILABLE_IN_ALL
322 void                  g_signal_emit         (gpointer            instance,
323                                              guint               signal_id,
324                                              GQuark              detail,
325                                              ...);
326 GLIB_AVAILABLE_IN_ALL
327 void                  g_signal_emit_by_name (gpointer            instance,
328                                              const gchar        *detailed_signal,
329                                              ...);
330 GLIB_AVAILABLE_IN_ALL
331 guint                 g_signal_lookup       (const gchar        *name,
332                                              GType               itype);
333 GLIB_AVAILABLE_IN_ALL
334 const gchar *         g_signal_name         (guint               signal_id);
335 GLIB_AVAILABLE_IN_ALL
336 void                  g_signal_query        (guint               signal_id,
337                                              GSignalQuery       *query);
338 GLIB_AVAILABLE_IN_ALL
339 guint*                g_signal_list_ids     (GType               itype,
340                                              guint              *n_ids);
341 GLIB_AVAILABLE_IN_ALL
342 gboolean              g_signal_parse_name   (const gchar        *detailed_signal,
343                                              GType               itype,
344                                              guint              *signal_id_p,
345                                              GQuark             *detail_p,
346                                              gboolean            force_detail_quark);
347 GLIB_AVAILABLE_IN_ALL
348 GSignalInvocationHint* g_signal_get_invocation_hint (gpointer    instance);
349
350
351 /* --- signal emissions --- */
352 GLIB_AVAILABLE_IN_ALL
353 void    g_signal_stop_emission              (gpointer             instance,
354                                              guint                signal_id,
355                                              GQuark               detail);
356 GLIB_AVAILABLE_IN_ALL
357 void    g_signal_stop_emission_by_name      (gpointer             instance,
358                                              const gchar         *detailed_signal);
359 GLIB_AVAILABLE_IN_ALL
360 gulong  g_signal_add_emission_hook          (guint                signal_id,
361                                              GQuark               detail,
362                                              GSignalEmissionHook  hook_func,
363                                              gpointer             hook_data,
364                                              GDestroyNotify       data_destroy);
365 GLIB_AVAILABLE_IN_ALL
366 void    g_signal_remove_emission_hook       (guint                signal_id,
367                                              gulong               hook_id);
368
369
370 /* --- signal handlers --- */
371 GLIB_AVAILABLE_IN_ALL
372 gboolean g_signal_has_handler_pending         (gpointer           instance,
373                                                guint              signal_id,
374                                                GQuark             detail,
375                                                gboolean           may_be_blocked);
376 GLIB_AVAILABLE_IN_ALL
377 gulong   g_signal_connect_closure_by_id       (gpointer           instance,
378                                                guint              signal_id,
379                                                GQuark             detail,
380                                                GClosure          *closure,
381                                                gboolean           after);
382 GLIB_AVAILABLE_IN_ALL
383 gulong   g_signal_connect_closure             (gpointer           instance,
384                                                const gchar       *detailed_signal,
385                                                GClosure          *closure,
386                                                gboolean           after);
387 GLIB_AVAILABLE_IN_ALL
388 gulong   g_signal_connect_data                (gpointer           instance,
389                                                const gchar       *detailed_signal,
390                                                GCallback          c_handler,
391                                                gpointer           data,
392                                                GClosureNotify     destroy_data,
393                                                GConnectFlags      connect_flags);
394 GLIB_AVAILABLE_IN_ALL
395 void     g_signal_handler_block               (gpointer           instance,
396                                                gulong             handler_id);
397 GLIB_AVAILABLE_IN_ALL
398 void     g_signal_handler_unblock             (gpointer           instance,
399                                                gulong             handler_id);
400 GLIB_AVAILABLE_IN_ALL
401 void     g_signal_handler_disconnect          (gpointer           instance,
402                                                gulong             handler_id);
403 GLIB_AVAILABLE_IN_ALL
404 gboolean g_signal_handler_is_connected        (gpointer           instance,
405                                                gulong             handler_id);
406 GLIB_AVAILABLE_IN_ALL
407 gulong   g_signal_handler_find                (gpointer           instance,
408                                                GSignalMatchType   mask,
409                                                guint              signal_id,
410                                                GQuark             detail,
411                                                GClosure          *closure,
412                                                gpointer           func,
413                                                gpointer           data);
414 GLIB_AVAILABLE_IN_ALL
415 guint    g_signal_handlers_block_matched      (gpointer           instance,
416                                                GSignalMatchType   mask,
417                                                guint              signal_id,
418                                                GQuark             detail,
419                                                GClosure          *closure,
420                                                gpointer           func,
421                                                gpointer           data);
422 GLIB_AVAILABLE_IN_ALL
423 guint    g_signal_handlers_unblock_matched    (gpointer           instance,
424                                                GSignalMatchType   mask,
425                                                guint              signal_id,
426                                                GQuark             detail,
427                                                GClosure          *closure,
428                                                gpointer           func,
429                                                gpointer           data);
430 GLIB_AVAILABLE_IN_ALL
431 guint    g_signal_handlers_disconnect_matched (gpointer           instance,
432                                                GSignalMatchType   mask,
433                                                guint              signal_id,
434                                                GQuark             detail,
435                                                GClosure          *closure,
436                                                gpointer           func,
437                                                gpointer           data);
438
439
440 /* --- overriding and chaining --- */
441 GLIB_AVAILABLE_IN_ALL
442 void    g_signal_override_class_closure       (guint              signal_id,
443                                                GType              instance_type,
444                                                GClosure          *class_closure);
445 GLIB_AVAILABLE_IN_ALL
446 void    g_signal_override_class_handler       (const gchar       *signal_name,
447                                                GType              instance_type,
448                                                GCallback          class_handler);
449 GLIB_AVAILABLE_IN_ALL
450 void    g_signal_chain_from_overridden        (const GValue      *instance_and_params,
451                                                GValue            *return_value);
452 GLIB_AVAILABLE_IN_ALL
453 void   g_signal_chain_from_overridden_handler (gpointer           instance,
454                                                ...);
455
456
457 /* --- convenience --- */
458 /**
459  * g_signal_connect:
460  * @instance: the instance to connect to.
461  * @detailed_signal: a string of the form "signal-name::detail".
462  * @c_handler: the #GCallback to connect.
463  * @data: data to pass to @c_handler calls.
464  * 
465  * Connects a #GCallback function to a signal for a particular object.
466  * 
467  * The handler will be called before the default handler of the signal.
468  * 
469  * Returns: the handler id (always greater than 0 for successful connections)
470  */
471 #define g_signal_connect(instance, detailed_signal, c_handler, data) \
472     g_signal_connect_data ((instance), (detailed_signal), (c_handler), (data), NULL, (GConnectFlags) 0)
473 /**
474  * g_signal_connect_after:
475  * @instance: the instance to connect to.
476  * @detailed_signal: a string of the form "signal-name::detail".
477  * @c_handler: the #GCallback to connect.
478  * @data: data to pass to @c_handler calls.
479  * 
480  * Connects a #GCallback function to a signal for a particular object.
481  * 
482  * The handler will be called after the default handler of the signal.
483  * 
484  * Returns: the handler id (always greater than 0 for successful connections)
485  */
486 #define g_signal_connect_after(instance, detailed_signal, c_handler, data) \
487     g_signal_connect_data ((instance), (detailed_signal), (c_handler), (data), NULL, G_CONNECT_AFTER)
488 /**
489  * g_signal_connect_swapped:
490  * @instance: the instance to connect to.
491  * @detailed_signal: a string of the form "signal-name::detail".
492  * @c_handler: the #GCallback to connect.
493  * @data: data to pass to @c_handler calls.
494  * 
495  * Connects a #GCallback function to a signal for a particular object.
496  * 
497  * The instance on which the signal is emitted and @data will be swapped when 
498  * calling the handler. This is useful when calling pre-existing functions to
499  * operate purely on the @data, rather than the @instance: swapping the
500  * parameters avoids the need to write a wrapper function.
501  *
502  * For example, this allows the shorter code:
503  * |[<!-- language="C" -->
504  * g_signal_connect_swapped (button, "clicked",
505  *                           (GCallback) gtk_widget_hide, other_widget);
506  * ]|
507  *
508  * Rather than the cumbersome:
509  * |[<!-- language="C" -->
510  * static void
511  * button_clicked_cb (GtkButton *button, GtkWidget *other_widget)
512  * {
513  *     gtk_widget_hide (other_widget);
514  * }
515  *
516  * …
517  *
518  * g_signal_connect (button, "clicked",
519  *                   (GCallback) button_clicked_cb, other_widget);
520  * ]|
521  * 
522  * Returns: the handler ID (always greater than 0 for successful connections)
523  */
524 #define g_signal_connect_swapped(instance, detailed_signal, c_handler, data) \
525     g_signal_connect_data ((instance), (detailed_signal), (c_handler), (data), NULL, G_CONNECT_SWAPPED)
526 /**
527  * g_signal_handlers_disconnect_by_func:
528  * @instance: The instance to remove handlers from.
529  * @func: The C closure callback of the handlers (useless for non-C closures).
530  * @data: The closure data of the handlers' closures.
531  * 
532  * Disconnects all handlers on an instance that match @func and @data.
533  * 
534  * Returns: The number of handlers that matched.
535  */
536 #define g_signal_handlers_disconnect_by_func(instance, func, data)                                              \
537     g_signal_handlers_disconnect_matched ((instance),                                                           \
538                                           (GSignalMatchType) (G_SIGNAL_MATCH_FUNC | G_SIGNAL_MATCH_DATA),       \
539                                           0, 0, NULL, (func), (data))
540
541 /**
542  * g_signal_handlers_disconnect_by_data:
543  * @instance: The instance to remove handlers from
544  * @data: the closure data of the handlers' closures
545  *
546  * Disconnects all handlers on an instance that match @data.
547  *
548  * Returns: The number of handlers that matched.
549  *
550  * Since: 2.32
551  */
552 #define g_signal_handlers_disconnect_by_data(instance, data) \
553   g_signal_handlers_disconnect_matched ((instance), G_SIGNAL_MATCH_DATA, 0, 0, NULL, NULL, (data))
554
555 /**
556  * g_signal_handlers_block_by_func:
557  * @instance: The instance to block handlers from.
558  * @func: The C closure callback of the handlers (useless for non-C closures).
559  * @data: The closure data of the handlers' closures.
560  * 
561  * Blocks all handlers on an instance that match @func and @data.
562  * 
563  * Returns: The number of handlers that matched.
564  */
565 #define g_signal_handlers_block_by_func(instance, func, data)                                                   \
566     g_signal_handlers_block_matched      ((instance),                                                           \
567                                           (GSignalMatchType) (G_SIGNAL_MATCH_FUNC | G_SIGNAL_MATCH_DATA),       \
568                                           0, 0, NULL, (func), (data))
569 /**
570  * g_signal_handlers_unblock_by_func:
571  * @instance: The instance to unblock handlers from.
572  * @func: The C closure callback of the handlers (useless for non-C closures).
573  * @data: The closure data of the handlers' closures.
574  * 
575  * Unblocks all handlers on an instance that match @func and @data.
576  * 
577  * Returns: The number of handlers that matched.
578  */
579 #define g_signal_handlers_unblock_by_func(instance, func, data)                                                 \
580     g_signal_handlers_unblock_matched    ((instance),                                                           \
581                                           (GSignalMatchType) (G_SIGNAL_MATCH_FUNC | G_SIGNAL_MATCH_DATA),       \
582                                           0, 0, NULL, (func), (data))
583
584
585 GLIB_AVAILABLE_IN_ALL
586 gboolean g_signal_accumulator_true_handled (GSignalInvocationHint *ihint,
587                                             GValue                *return_accu,
588                                             const GValue          *handler_return,
589                                             gpointer               dummy);
590
591 GLIB_AVAILABLE_IN_ALL
592 gboolean g_signal_accumulator_first_wins   (GSignalInvocationHint *ihint,
593                                             GValue                *return_accu,
594                                             const GValue          *handler_return,
595                                             gpointer               dummy);
596
597 /*< private >*/
598 GLIB_AVAILABLE_IN_ALL
599 void     g_signal_handlers_destroy            (gpointer           instance);
600 void     _g_signals_destroy                   (GType              itype);
601
602 G_END_DECLS
603
604 #endif /* __G_SIGNAL_H__ */