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 2.1 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
29G_BEGIN_DECLS
30
31/* --- typedefs --- */
32typedef struct _GSignalQuery GSignalQuery;
33typedef 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.
40 *
41 * It is merely an alias to #GClosureMarshal since the #GClosure mechanism
42 * takes over responsibility of actual function invocation for the signal
43 * system.
44 */
45typedef GClosureMarshal GSignalCMarshaller;
46/**
47 * GSignalCVaMarshaller:
48 *
49 * This is the signature of va_list marshaller functions, an optional
50 * marshaller that can be used in some situations to avoid
51 * marshalling the signal argument into GValues.
52 */
53typedef GVaClosureMarshal GSignalCVaMarshaller;
54/**
55 * GSignalEmissionHook:
56 * @ihint: Signal invocation hint, see #GSignalInvocationHint.
57 * @n_param_values: the number of parameters to the function, including
58 * the instance on which the signal was emitted.
59 * @param_values: (array length=n_param_values): the instance on which
60 * the signal was emitted, followed by the parameters of the emission.
61 * @data: user data associated with the hook.
62 *
63 * A simple function pointer to get invoked when the signal is emitted.
64 *
65 * Emission hooks allow you to tie a hook to the signal type, so that it will
66 * trap all emissions of that signal, from any object.
67 *
68 * You may not attach these to signals created with the %G_SIGNAL_NO_HOOKS flag.
69 *
70 * Returns: whether it wants to stay connected. If it returns %FALSE, the signal
71 * hook is disconnected (and destroyed).
72 */
73typedef gboolean (*GSignalEmissionHook) (GSignalInvocationHint *ihint,
74 guint n_param_values,
75 const GValue *param_values,
76 gpointer data);
77/**
78 * GSignalAccumulator:
79 * @ihint: Signal invocation hint, see #GSignalInvocationHint.
80 * @return_accu: Accumulator to collect callback return values in, this
81 * is the return value of the current signal emission.
82 * @handler_return: A #GValue holding the return value of the signal handler.
83 * @data: Callback data that was specified when creating the signal.
84 *
85 * The signal accumulator is a special callback function that can be used
86 * to collect return values of the various callbacks that are called
87 * during a signal emission.
88 *
89 * The signal accumulator is specified at signal creation time, if it is
90 * left %NULL, no accumulation of callback return values is performed.
91 * The return value of signal emissions is then the value returned by the
92 * last callback.
93 *
94 * Returns: The accumulator function returns whether the signal emission
95 * should be aborted. Returning %TRUE will continue with
96 * the signal emission. Returning %FALSE will abort the current emission.
97 * Since 2.62, returning %FALSE will skip to the CLEANUP stage. In this case,
98 * emission will occur as normal in the CLEANUP stage and the handler's
99 * return value will be accumulated.
100 */
101typedef gboolean (*GSignalAccumulator) (GSignalInvocationHint *ihint,
102 GValue *return_accu,
103 const GValue *handler_return,
104 gpointer data);
105
106
107/* --- run, match and connect types --- */
108/**
109 * GSignalFlags:
110 * @G_SIGNAL_RUN_FIRST: Invoke the object method handler in the first emission stage.
111 * @G_SIGNAL_RUN_LAST: Invoke the object method handler in the third emission stage.
112 * @G_SIGNAL_RUN_CLEANUP: Invoke the object method handler in the last emission stage.
113 * @G_SIGNAL_NO_RECURSE: Signals being emitted for an object while currently being in
114 * emission for this very object will not be emitted recursively,
115 * but instead cause the first emission to be restarted.
116 * @G_SIGNAL_DETAILED: This signal supports "::detail" appendices to the signal name
117 * upon handler connections and emissions.
118 * @G_SIGNAL_ACTION: Action signals are signals that may freely be emitted on alive
119 * objects from user code via g_signal_emit() and friends, without
120 * the need of being embedded into extra code that performs pre or
121 * post emission adjustments on the object. They can also be thought
122 * of as object methods which can be called generically by
123 * third-party code.
124 * @G_SIGNAL_NO_HOOKS: No emissions hooks are supported for this signal.
125 * @G_SIGNAL_MUST_COLLECT: Varargs signal emission will always collect the
126 * arguments, even if there are no signal handlers connected. Since 2.30.
127 * @G_SIGNAL_DEPRECATED: The signal is deprecated and will be removed
128 * in a future version. A warning will be generated if it is connected while
129 * running with G_ENABLE_DIAGNOSTIC=1. Since 2.32.
130 * @G_SIGNAL_ACCUMULATOR_FIRST_RUN: Only used in #GSignalAccumulator accumulator
131 * functions for the #GSignalInvocationHint::run_type field to mark the first
132 * call to the accumulator function for a signal emission. Since 2.68.
133 *
134 * The signal flags are used to specify a signal's behaviour.
135 */
136typedef enum
137{
138 G_SIGNAL_RUN_FIRST = 1 << 0,
139 G_SIGNAL_RUN_LAST = 1 << 1,
140 G_SIGNAL_RUN_CLEANUP = 1 << 2,
141 G_SIGNAL_NO_RECURSE = 1 << 3,
142 G_SIGNAL_DETAILED = 1 << 4,
143 G_SIGNAL_ACTION = 1 << 5,
144 G_SIGNAL_NO_HOOKS = 1 << 6,
145 G_SIGNAL_MUST_COLLECT = 1 << 7,
146 G_SIGNAL_DEPRECATED = 1 << 8,
147 /* normal signal flags until 1 << 16 */
148 G_SIGNAL_ACCUMULATOR_FIRST_RUN = 1 << 17,
149} GSignalFlags;
150/**
151 * G_SIGNAL_FLAGS_MASK:
152 *
153 * A mask for all #GSignalFlags bits.
154 */
155#define G_SIGNAL_FLAGS_MASK 0x1ff
156/**
157 * GConnectFlags:
158 * @G_CONNECT_AFTER: whether the handler should be called before or after the
159 * default handler of the signal.
160 * @G_CONNECT_SWAPPED: whether the instance and data should be swapped when
161 * calling the handler; see g_signal_connect_swapped() for an example.
162 *
163 * The connection flags are used to specify the behaviour of a signal's
164 * connection.
165 */
166typedef enum
167{
168 G_CONNECT_AFTER = 1 << 0,
169 G_CONNECT_SWAPPED = 1 << 1
170} GConnectFlags;
171/**
172 * GSignalMatchType:
173 * @G_SIGNAL_MATCH_ID: The signal id must be equal.
174 * @G_SIGNAL_MATCH_DETAIL: The signal detail must be equal.
175 * @G_SIGNAL_MATCH_CLOSURE: The closure must be the same.
176 * @G_SIGNAL_MATCH_FUNC: The C closure callback must be the same.
177 * @G_SIGNAL_MATCH_DATA: The closure data must be the same.
178 * @G_SIGNAL_MATCH_UNBLOCKED: Only unblocked signals may be matched.
179 *
180 * The match types specify what g_signal_handlers_block_matched(),
181 * g_signal_handlers_unblock_matched() and g_signal_handlers_disconnect_matched()
182 * match signals by.
183 */
184typedef enum
185{
186 G_SIGNAL_MATCH_ID = 1 << 0,
187 G_SIGNAL_MATCH_DETAIL = 1 << 1,
188 G_SIGNAL_MATCH_CLOSURE = 1 << 2,
189 G_SIGNAL_MATCH_FUNC = 1 << 3,
190 G_SIGNAL_MATCH_DATA = 1 << 4,
191 G_SIGNAL_MATCH_UNBLOCKED = 1 << 5
192} GSignalMatchType;
193/**
194 * G_SIGNAL_MATCH_MASK:
195 *
196 * A mask for all #GSignalMatchType bits.
197 */
198#define G_SIGNAL_MATCH_MASK 0x3f
199/**
200 * G_SIGNAL_TYPE_STATIC_SCOPE:
201 *
202 * This macro flags signal argument types for which the signal system may
203 * assume that instances thereof remain persistent across all signal emissions
204 * they are used in. This is only useful for non ref-counted, value-copy types.
205 *
206 * To flag a signal argument in this way, add `| G_SIGNAL_TYPE_STATIC_SCOPE`
207 * to the corresponding argument of g_signal_new().
208 * |[
209 * g_signal_new ("size_request",
210 * G_TYPE_FROM_CLASS (gobject_class),
211 * G_SIGNAL_RUN_FIRST,
212 * G_STRUCT_OFFSET (GtkWidgetClass, size_request),
213 * NULL, NULL,
214 * _gtk_marshal_VOID__BOXED,
215 * G_TYPE_NONE, 1,
216 * GTK_TYPE_REQUISITION | G_SIGNAL_TYPE_STATIC_SCOPE);
217 * ]|
218 */
219#define G_SIGNAL_TYPE_STATIC_SCOPE (G_TYPE_FLAG_RESERVED_ID_BIT)
220
221
222/* --- signal information --- */
223/**
224 * GSignalInvocationHint:
225 * @signal_id: The signal id of the signal invoking the callback
226 * @detail: The detail passed on for this emission
227 * @run_type: The stage the signal emission is currently in, this
228 * field will contain one of %G_SIGNAL_RUN_FIRST,
229 * %G_SIGNAL_RUN_LAST or %G_SIGNAL_RUN_CLEANUP and %G_SIGNAL_ACCUMULATOR_FIRST_RUN.
230 * %G_SIGNAL_ACCUMULATOR_FIRST_RUN is only set for the first run of the accumulator
231 * function for a signal emission.
232 *
233 * The #GSignalInvocationHint structure is used to pass on additional information
234 * to callbacks during a signal emission.
235 */
236struct _GSignalInvocationHint
237{
238 guint signal_id;
239 GQuark detail;
240 GSignalFlags run_type;
241};
242/**
243 * GSignalQuery:
244 * @signal_id: The signal id of the signal being queried, or 0 if the
245 * signal to be queried was unknown.
246 * @signal_name: The signal name.
247 * @itype: The interface/instance type that this signal can be emitted for.
248 * @signal_flags: The signal flags as passed in to g_signal_new().
249 * @return_type: The return type for user callbacks.
250 * @n_params: The number of parameters that user callbacks take.
251 * @param_types: (array length=n_params): The individual parameter types for
252 * user callbacks, note that the effective callback signature is:
253 * |[<!-- language="C" -->
254 * @return_type callback (#gpointer data1,
255 * [param_types param_names,]
256 * gpointer data2);
257 * ]|
258 *
259 * A structure holding in-depth information for a specific signal.
260 *
261 * See also: g_signal_query()
262 */
263struct _GSignalQuery
264{
265 guint signal_id;
266 const gchar *signal_name;
267 GType itype;
268 GSignalFlags signal_flags;
269 GType return_type; /* mangled with G_SIGNAL_TYPE_STATIC_SCOPE flag */
270 guint n_params;
271 const GType *param_types; /* mangled with G_SIGNAL_TYPE_STATIC_SCOPE flag */
272};
273
274
275/* --- signals --- */
276GLIB_AVAILABLE_IN_ALL
277guint g_signal_newv (const gchar *signal_name,
278 GType itype,
279 GSignalFlags signal_flags,
280 GClosure *class_closure,
281 GSignalAccumulator accumulator,
282 gpointer accu_data,
283 GSignalCMarshaller c_marshaller,
284 GType return_type,
285 guint n_params,
286 GType *param_types);
287GLIB_AVAILABLE_IN_ALL
288guint g_signal_new_valist (const gchar *signal_name,
289 GType itype,
290 GSignalFlags signal_flags,
291 GClosure *class_closure,
292 GSignalAccumulator accumulator,
293 gpointer accu_data,
294 GSignalCMarshaller c_marshaller,
295 GType return_type,
296 guint n_params,
297 va_list args);
298GLIB_AVAILABLE_IN_ALL
299guint g_signal_new (const gchar *signal_name,
300 GType itype,
301 GSignalFlags signal_flags,
302 guint class_offset,
303 GSignalAccumulator accumulator,
304 gpointer accu_data,
305 GSignalCMarshaller c_marshaller,
306 GType return_type,
307 guint n_params,
308 ...);
309GLIB_AVAILABLE_IN_ALL
310guint g_signal_new_class_handler (const gchar *signal_name,
311 GType itype,
312 GSignalFlags signal_flags,
313 GCallback class_handler,
314 GSignalAccumulator accumulator,
315 gpointer accu_data,
316 GSignalCMarshaller c_marshaller,
317 GType return_type,
318 guint n_params,
319 ...);
320GLIB_AVAILABLE_IN_ALL
321void g_signal_set_va_marshaller (guint signal_id,
322 GType instance_type,
323 GSignalCVaMarshaller va_marshaller);
324
325GLIB_AVAILABLE_IN_ALL
326void g_signal_emitv (const GValue *instance_and_params,
327 guint signal_id,
328 GQuark detail,
329 GValue *return_value);
330GLIB_AVAILABLE_IN_ALL
331void g_signal_emit_valist (gpointer instance,
332 guint signal_id,
333 GQuark detail,
334 va_list var_args);
335GLIB_AVAILABLE_IN_ALL
336void g_signal_emit (gpointer instance,
337 guint signal_id,
338 GQuark detail,
339 ...);
340GLIB_AVAILABLE_IN_ALL
341void g_signal_emit_by_name (gpointer instance,
342 const gchar *detailed_signal,
343 ...);
344GLIB_AVAILABLE_IN_ALL
345guint g_signal_lookup (const gchar *name,
346 GType itype);
347GLIB_AVAILABLE_IN_ALL
348const gchar * g_signal_name (guint signal_id);
349GLIB_AVAILABLE_IN_ALL
350void g_signal_query (guint signal_id,
351 GSignalQuery *query);
352GLIB_AVAILABLE_IN_ALL
353guint* g_signal_list_ids (GType itype,
354 guint *n_ids);
355GLIB_AVAILABLE_IN_2_66
356gboolean g_signal_is_valid_name (const gchar *name);
357GLIB_AVAILABLE_IN_ALL
358gboolean g_signal_parse_name (const gchar *detailed_signal,
359 GType itype,
360 guint *signal_id_p,
361 GQuark *detail_p,
362 gboolean force_detail_quark);
363GLIB_AVAILABLE_IN_ALL
364GSignalInvocationHint* g_signal_get_invocation_hint (gpointer instance);
365
366
367/* --- signal emissions --- */
368GLIB_AVAILABLE_IN_ALL
369void g_signal_stop_emission (gpointer instance,
370 guint signal_id,
371 GQuark detail);
372GLIB_AVAILABLE_IN_ALL
373void g_signal_stop_emission_by_name (gpointer instance,
374 const gchar *detailed_signal);
375GLIB_AVAILABLE_IN_ALL
376gulong g_signal_add_emission_hook (guint signal_id,
377 GQuark detail,
378 GSignalEmissionHook hook_func,
379 gpointer hook_data,
380 GDestroyNotify data_destroy);
381GLIB_AVAILABLE_IN_ALL
382void g_signal_remove_emission_hook (guint signal_id,
383 gulong hook_id);
384
385
386/* --- signal handlers --- */
387GLIB_AVAILABLE_IN_ALL
388gboolean g_signal_has_handler_pending (gpointer instance,
389 guint signal_id,
390 GQuark detail,
391 gboolean may_be_blocked);
392GLIB_AVAILABLE_IN_ALL
393gulong g_signal_connect_closure_by_id (gpointer instance,
394 guint signal_id,
395 GQuark detail,
396 GClosure *closure,
397 gboolean after);
398GLIB_AVAILABLE_IN_ALL
399gulong g_signal_connect_closure (gpointer instance,
400 const gchar *detailed_signal,
401 GClosure *closure,
402 gboolean after);
403GLIB_AVAILABLE_IN_ALL
404gulong g_signal_connect_data (gpointer instance,
405 const gchar *detailed_signal,
406 GCallback c_handler,
407 gpointer data,
408 GClosureNotify destroy_data,
409 GConnectFlags connect_flags);
410GLIB_AVAILABLE_IN_ALL
411void g_signal_handler_block (gpointer instance,
412 gulong handler_id);
413GLIB_AVAILABLE_IN_ALL
414void g_signal_handler_unblock (gpointer instance,
415 gulong handler_id);
416GLIB_AVAILABLE_IN_ALL
417void g_signal_handler_disconnect (gpointer instance,
418 gulong handler_id);
419GLIB_AVAILABLE_IN_ALL
420gboolean g_signal_handler_is_connected (gpointer instance,
421 gulong handler_id);
422GLIB_AVAILABLE_IN_ALL
423gulong g_signal_handler_find (gpointer instance,
424 GSignalMatchType mask,
425 guint signal_id,
426 GQuark detail,
427 GClosure *closure,
428 gpointer func,
429 gpointer data);
430GLIB_AVAILABLE_IN_ALL
431guint g_signal_handlers_block_matched (gpointer instance,
432 GSignalMatchType mask,
433 guint signal_id,
434 GQuark detail,
435 GClosure *closure,
436 gpointer func,
437 gpointer data);
438GLIB_AVAILABLE_IN_ALL
439guint g_signal_handlers_unblock_matched (gpointer instance,
440 GSignalMatchType mask,
441 guint signal_id,
442 GQuark detail,
443 GClosure *closure,
444 gpointer func,
445 gpointer data);
446GLIB_AVAILABLE_IN_ALL
447guint g_signal_handlers_disconnect_matched (gpointer instance,
448 GSignalMatchType mask,
449 guint signal_id,
450 GQuark detail,
451 GClosure *closure,
452 gpointer func,
453 gpointer data);
454
455GLIB_AVAILABLE_IN_2_62
456void g_clear_signal_handler (gulong *handler_id_ptr,
457 gpointer instance);
458
459#define g_clear_signal_handler(handler_id_ptr, instance) \
460 G_STMT_START { \
461 gpointer const _instance = (instance); \
462 gulong *const _handler_id_ptr = (handler_id_ptr); \
463 const gulong _handler_id = *_handler_id_ptr; \
464 \
465 if (_handler_id > 0) \
466 { \
467 *_handler_id_ptr = 0; \
468 g_signal_handler_disconnect (_instance, _handler_id); \
469 } \
470 } G_STMT_END \
471 GLIB_AVAILABLE_MACRO_IN_2_62
472
473/* --- overriding and chaining --- */
474GLIB_AVAILABLE_IN_ALL
475void g_signal_override_class_closure (guint signal_id,
476 GType instance_type,
477 GClosure *class_closure);
478GLIB_AVAILABLE_IN_ALL
479void g_signal_override_class_handler (const gchar *signal_name,
480 GType instance_type,
481 GCallback class_handler);
482GLIB_AVAILABLE_IN_ALL
483void g_signal_chain_from_overridden (const GValue *instance_and_params,
484 GValue *return_value);
485GLIB_AVAILABLE_IN_ALL
486void g_signal_chain_from_overridden_handler (gpointer instance,
487 ...);
488
489
490/* --- convenience --- */
491/**
492 * g_signal_connect:
493 * @instance: the instance to connect to.
494 * @detailed_signal: a string of the form "signal-name::detail".
495 * @c_handler: the #GCallback to connect.
496 * @data: data to pass to @c_handler calls.
497 *
498 * Connects a #GCallback function to a signal for a particular object.
499 *
500 * The handler will be called synchronously, before the default handler of the signal. g_signal_emit() will not return control until all handlers are called.
501 *
502 * See [memory management of signal handlers][signal-memory-management] for
503 * details on how to handle the return value and memory management of @data.
504 *
505 * Returns: the handler ID, of type #gulong (always greater than 0 for successful connections)
506 */
507#define g_signal_connect(instance, detailed_signal, c_handler, data) \
508 g_signal_connect_data ((instance), (detailed_signal), (c_handler), (data), NULL, (GConnectFlags) 0)
509/**
510 * g_signal_connect_after:
511 * @instance: the instance to connect to.
512 * @detailed_signal: a string of the form "signal-name::detail".
513 * @c_handler: the #GCallback to connect.
514 * @data: data to pass to @c_handler calls.
515 *
516 * Connects a #GCallback function to a signal for a particular object.
517 *
518 * The handler will be called synchronously, after the default handler of the signal.
519 *
520 * Returns: the handler ID, of type #gulong (always greater than 0 for successful connections)
521 */
522#define g_signal_connect_after(instance, detailed_signal, c_handler, data) \
523 g_signal_connect_data ((instance), (detailed_signal), (c_handler), (data), NULL, G_CONNECT_AFTER)
524/**
525 * g_signal_connect_swapped:
526 * @instance: the instance to connect to.
527 * @detailed_signal: a string of the form "signal-name::detail".
528 * @c_handler: the #GCallback to connect.
529 * @data: data to pass to @c_handler calls.
530 *
531 * Connects a #GCallback function to a signal for a particular object.
532 *
533 * The instance on which the signal is emitted and @data will be swapped when
534 * calling the handler. This is useful when calling pre-existing functions to
535 * operate purely on the @data, rather than the @instance: swapping the
536 * parameters avoids the need to write a wrapper function.
537 *
538 * For example, this allows the shorter code:
539 * |[<!-- language="C" -->
540 * g_signal_connect_swapped (button, "clicked",
541 * (GCallback) gtk_widget_hide, other_widget);
542 * ]|
543 *
544 * Rather than the cumbersome:
545 * |[<!-- language="C" -->
546 * static void
547 * button_clicked_cb (GtkButton *button, GtkWidget *other_widget)
548 * {
549 * gtk_widget_hide (other_widget);
550 * }
551 *
552 * ...
553 *
554 * g_signal_connect (button, "clicked",
555 * (GCallback) button_clicked_cb, other_widget);
556 * ]|
557 *
558 * Returns: the handler ID, of type #gulong (always greater than 0 for successful connections)
559 */
560#define g_signal_connect_swapped(instance, detailed_signal, c_handler, data) \
561 g_signal_connect_data ((instance), (detailed_signal), (c_handler), (data), NULL, G_CONNECT_SWAPPED)
562/**
563 * g_signal_handlers_disconnect_by_func:
564 * @instance: The instance to remove handlers from.
565 * @func: The C closure callback of the handlers (useless for non-C closures).
566 * @data: The closure data of the handlers' closures.
567 *
568 * Disconnects all handlers on an instance that match @func and @data.
569 *
570 * Returns: The number of handlers that matched.
571 */
572#define g_signal_handlers_disconnect_by_func(instance, func, data) \
573 g_signal_handlers_disconnect_matched ((instance), \
574 (GSignalMatchType) (G_SIGNAL_MATCH_FUNC | G_SIGNAL_MATCH_DATA), \
575 0, 0, NULL, (func), (data))
576
577/**
578 * g_signal_handlers_disconnect_by_data:
579 * @instance: The instance to remove handlers from
580 * @data: the closure data of the handlers' closures
581 *
582 * Disconnects all handlers on an instance that match @data.
583 *
584 * Returns: The number of handlers that matched.
585 *
586 * Since: 2.32
587 */
588#define g_signal_handlers_disconnect_by_data(instance, data) \
589 g_signal_handlers_disconnect_matched ((instance), G_SIGNAL_MATCH_DATA, 0, 0, NULL, NULL, (data))
590
591/**
592 * g_signal_handlers_block_by_func:
593 * @instance: The instance to block handlers from.
594 * @func: The C closure callback of the handlers (useless for non-C closures).
595 * @data: The closure data of the handlers' closures.
596 *
597 * Blocks all handlers on an instance that match @func and @data.
598 *
599 * Returns: The number of handlers that matched.
600 */
601#define g_signal_handlers_block_by_func(instance, func, data) \
602 g_signal_handlers_block_matched ((instance), \
603 (GSignalMatchType) (G_SIGNAL_MATCH_FUNC | G_SIGNAL_MATCH_DATA), \
604 0, 0, NULL, (func), (data))
605/**
606 * g_signal_handlers_unblock_by_func:
607 * @instance: The instance to unblock handlers from.
608 * @func: The C closure callback of the handlers (useless for non-C closures).
609 * @data: The closure data of the handlers' closures.
610 *
611 * Unblocks all handlers on an instance that match @func and @data.
612 *
613 * Returns: The number of handlers that matched.
614 */
615#define g_signal_handlers_unblock_by_func(instance, func, data) \
616 g_signal_handlers_unblock_matched ((instance), \
617 (GSignalMatchType) (G_SIGNAL_MATCH_FUNC | G_SIGNAL_MATCH_DATA), \
618 0, 0, NULL, (func), (data))
619
620
621GLIB_AVAILABLE_IN_ALL
622gboolean g_signal_accumulator_true_handled (GSignalInvocationHint *ihint,
623 GValue *return_accu,
624 const GValue *handler_return,
625 gpointer dummy);
626
627GLIB_AVAILABLE_IN_ALL
628gboolean g_signal_accumulator_first_wins (GSignalInvocationHint *ihint,
629 GValue *return_accu,
630 const GValue *handler_return,
631 gpointer dummy);
632
633/*< private >*/
634GLIB_AVAILABLE_IN_ALL
635void g_signal_handlers_destroy (gpointer instance);
636void _g_signals_destroy (GType itype);
637
638G_END_DECLS
639
640#endif /* __G_SIGNAL_H__ */
641

source code of include/glib-2.0/gobject/gsignal.h