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 2.1 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
  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  * See [memory management of signal handlers][signal-memory-management] for
 470  * details on how to handle the return value and memory management of @data.
 471  *
 472  * Returns: the handler ID, of type #gulong (always greater than 0 for successful connections)
 473  */
 474 #define g_signal_connect(instance, detailed_signal, c_handler, data) \
 475     g_signal_connect_data ((instance), (detailed_signal), (c_handler), (data), NULL, (GConnectFlags) 0)
 476 /**
 477  * g_signal_connect_after:
 478  * @instance: the instance to connect to.
 479  * @detailed_signal: a string of the form "signal-name::detail".
 480  * @c_handler: the #GCallback to connect.
 481  * @data: data to pass to @c_handler calls.
 482  *
 483  * Connects a #GCallback function to a signal for a particular object.
 484  *
 485  * The handler will be called after the default handler of the signal.
 486  *
 487  * Returns: the handler ID, of type #gulong (always greater than 0 for successful connections)
 488  */
 489 #define g_signal_connect_after(instance, detailed_signal, c_handler, data) \
 490     g_signal_connect_data ((instance), (detailed_signal), (c_handler), (data), NULL, G_CONNECT_AFTER)
 491 /**
 492  * g_signal_connect_swapped:
 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 instance on which the signal is emitted and @data will be swapped when
 501  * calling the handler. This is useful when calling pre-existing functions to
 502  * operate purely on the @data, rather than the @instance: swapping the
 503  * parameters avoids the need to write a wrapper function.
 504  *
 505  * For example, this allows the shorter code:
 506  * |[<!-- language="C" -->
 507  * g_signal_connect_swapped (button, "clicked",
 508  *                           (GCallback) gtk_widget_hide, other_widget);
 509  * ]|
 510  *
 511  * Rather than the cumbersome:
 512  * |[<!-- language="C" -->
 513  * static void
 514  * button_clicked_cb (GtkButton *button, GtkWidget *other_widget)
 515  * {
 516  *     gtk_widget_hide (other_widget);
 517  * }
 518  *
 519  * ...
 520  *
 521  * g_signal_connect (button, "clicked",
 522  *                   (GCallback) button_clicked_cb, other_widget);
 523  * ]|
 524  *
 525  * Returns: the handler ID, of type #gulong (always greater than 0 for successful connections)
 526  */
 527 #define g_signal_connect_swapped(instance, detailed_signal, c_handler, data) \
 528     g_signal_connect_data ((instance), (detailed_signal), (c_handler), (data), NULL, G_CONNECT_SWAPPED)
 529 /**
 530  * g_signal_handlers_disconnect_by_func:
 531  * @instance: The instance to remove handlers from.
 532  * @func: The C closure callback of the handlers (useless for non-C closures).
 533  * @data: The closure data of the handlers' closures.
 534  *
 535  * Disconnects all handlers on an instance that match @func and @data.
 536  *
 537  * Returns: The number of handlers that matched.
 538  */
 539 #define g_signal_handlers_disconnect_by_func(instance, func, data)                                              \
 540     g_signal_handlers_disconnect_matched ((instance),                                                           \
 541                                           (GSignalMatchType) (G_SIGNAL_MATCH_FUNC | G_SIGNAL_MATCH_DATA),       \
 542                                           0, 0, NULL, (func), (data))
 543
 544 /**
 545  * g_signal_handlers_disconnect_by_data:
 546  * @instance: The instance to remove handlers from
 547  * @data: the closure data of the handlers' closures
 548  *
 549  * Disconnects all handlers on an instance that match @data.
 550  *
 551  * Returns: The number of handlers that matched.
 552  *
 553  * Since: 2.32
 554  */
 555 #define g_signal_handlers_disconnect_by_data(instance, data) \
 556   g_signal_handlers_disconnect_matched ((instance), G_SIGNAL_MATCH_DATA, 0, 0, NULL, NULL, (data))
 557
 558 /**
 559  * g_signal_handlers_block_by_func:
 560  * @instance: The instance to block handlers from.
 561  * @func: The C closure callback of the handlers (useless for non-C closures).
 562  * @data: The closure data of the handlers' closures.
 563  *
 564  * Blocks all handlers on an instance that match @func and @data.
 565  *
 566  * Returns: The number of handlers that matched.
 567  */
 568 #define g_signal_handlers_block_by_func(instance, func, data)                                                   \
 569     g_signal_handlers_block_matched      ((instance),                                                           \
 570                                           (GSignalMatchType) (G_SIGNAL_MATCH_FUNC | G_SIGNAL_MATCH_DATA),       \
 571                                           0, 0, NULL, (func), (data))
 572 /**
 573  * g_signal_handlers_unblock_by_func:
 574  * @instance: The instance to unblock handlers from.
 575  * @func: The C closure callback of the handlers (useless for non-C closures).
 576  * @data: The closure data of the handlers' closures.
 577  *
 578  * Unblocks all handlers on an instance that match @func and @data.
 579  *
 580  * Returns: The number of handlers that matched.
 581  */
 582 #define g_signal_handlers_unblock_by_func(instance, func, data)                                                 \
 583     g_signal_handlers_unblock_matched    ((instance),                                                           \
 584                                           (GSignalMatchType) (G_SIGNAL_MATCH_FUNC | G_SIGNAL_MATCH_DATA),       \
 585                                           0, 0, NULL, (func), (data))
 586
 587
 588 GLIB_AVAILABLE_IN_ALL
 589 gboolean g_signal_accumulator_true_handled (GSignalInvocationHint *ihint,
 590                                             GValue                *return_accu,
 591                                             const GValue          *handler_return,
 592                                             gpointer               dummy);
 593
 594 GLIB_AVAILABLE_IN_ALL
 595 gboolean g_signal_accumulator_first_wins   (GSignalInvocationHint *ihint,
 596                                             GValue                *return_accu,
 597                                             const GValue          *handler_return,
 598                                             gpointer               dummy);
 599
 600 /*< private >*/
 601 GLIB_AVAILABLE_IN_ALL
 602 void     g_signal_handlers_destroy            (gpointer           instance);
 603 void     _g_signals_destroy                   (GType              itype);
 604
 605 G_END_DECLS
 606
 607 #endif /* __G_SIGNAL_H__ */