[kdbus] Do not set body message if signature field is empty
[platform/upstream/glib.git] / gobject / gsignal.h
index bc2f75c..c0b0681 100644 (file)
@@ -1,5 +1,5 @@
 /* GObject - GLib Type, Object, Parameter and Signal Library
- * Copyright (C) 2000 Red Hat, Inc.
+ * Copyright (C) 2000-2001 Red Hat, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.         See the GNU
  * Lesser General Public License for more details.
  *
  * You should have received a copy of the GNU Lesser General
- * Public License along with this library; if not, write to the
- * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
- * Boston, MA 02111-1307, USA.
+ * Public License along with this library; if not, see <http://www.gnu.org/licenses/>.
  */
 #ifndef __G_SIGNAL_H__
 #define __G_SIGNAL_H__
 
+#if !defined (__GLIB_GOBJECT_H_INSIDE__) && !defined (GOBJECT_COMPILATION)
+#error "Only <glib-object.h> can be included directly."
+#endif
 
 #include       <gobject/gclosure.h>
 #include       <gobject/gvalue.h>
 #include       <gobject/gparam.h>
+#include       <gobject/gmarshal.h>
 
-
-#ifdef __cplusplus
-extern "C" {
-#endif /* __cplusplus */
-
+G_BEGIN_DECLS
 
 /* --- typedefs --- */
-typedef struct _GSignalQuery            GSignalQuery;
-typedef struct _GSignalInvocationHint   GSignalInvocationHint;
-typedef        GClosureMarshal                  GSignalCMarshaller;
+typedef struct _GSignalQuery            GSignalQuery;
+typedef struct _GSignalInvocationHint   GSignalInvocationHint;
+/**
+ * GSignalCMarshaller:
+ * 
+ * This is the signature of marshaller functions, required to marshall
+ * arrays of parameter values to signal emissions into C language callback
+ * invocations. It is merely an alias to #GClosureMarshal since the #GClosure
+ * mechanism takes over responsibility of actual function invocation for the
+ * signal system.
+ */
+typedef GClosureMarshal                         GSignalCMarshaller;
+/**
+ * GSignalCVaMarshaller:
+ * 
+ * This is the signature of va_list marshaller functions, an optional
+ * marshaller that can be used in some situations to avoid
+ * marshalling the signal argument into GValues.
+ */
+typedef GVaClosureMarshal               GSignalCVaMarshaller;
+/**
+ * GSignalEmissionHook:
+ * @ihint: Signal invocation hint, see #GSignalInvocationHint.
+ * @n_param_values: the number of parameters to the function, including
+ *  the instance on which the signal was emitted.
+ * @param_values: (array length=n_param_values): the instance on which
+ *  the signal was emitted, followed by the parameters of the emission.
+ * @data: user data associated with the hook.
+ * 
+ * A simple function pointer to get invoked when the signal is emitted. This 
+ * allows you to tie a hook to the signal type, so that it will trap all 
+ * emissions of that signal, from any object.
+ * 
+ * You may not attach these to signals created with the #G_SIGNAL_NO_HOOKS flag.
+ * 
+ * Returns: whether it wants to stay connected. If it returns %FALSE, the signal 
+ *  hook is disconnected (and destroyed).
+ */
 typedef gboolean (*GSignalEmissionHook) (GSignalInvocationHint *ihint,
                                         guint                  n_param_values,
-                                        const GValue          *param_values);
+                                        const GValue          *param_values,
+                                        gpointer               data);
+/**
+ * GSignalAccumulator:
+ * @ihint: Signal invocation hint, see #GSignalInvocationHint.
+ * @return_accu: Accumulator to collect callback return values in, this
+ *  is the return value of the current signal emission.
+ * @handler_return: A #GValue holding the return value of the signal handler.
+ * @data: Callback data that was specified when creating the signal.
+ * 
+ * The signal accumulator is a special callback function that can be used
+ * to collect return values of the various callbacks that are called
+ * during a signal emission. The signal accumulator is specified at signal
+ * creation time, if it is left %NULL, no accumulation of callback return
+ * values is performed. The return value of signal emissions is then the
+ * value returned by the last callback.
+ * 
+ * Returns: The accumulator function returns whether the signal emission
+ *  should be aborted. Returning %FALSE means to abort the
+ *  current emission and %TRUE is returned for continuation.
+ */
 typedef gboolean (*GSignalAccumulator) (GSignalInvocationHint *ihint,
                                         GValue                *return_accu,
-                                        const GValue          *return_value);
+                                        const GValue          *handler_return,
+                                        gpointer               data);
 
 
-/* --- run & match types --- */
+/* --- run, match and connect types --- */
+/**
+ * GSignalFlags:
+ * @G_SIGNAL_RUN_FIRST: Invoke the object method handler in the first emission stage.
+ * @G_SIGNAL_RUN_LAST: Invoke the object method handler in the third emission stage.
+ * @G_SIGNAL_RUN_CLEANUP: Invoke the object method handler in the last emission stage.
+ * @G_SIGNAL_NO_RECURSE: Signals being emitted for an object while currently being in
+ *  emission for this very object will not be emitted recursively,
+ *  but instead cause the first emission to be restarted.
+ * @G_SIGNAL_DETAILED: This signal supports "::detail" appendices to the signal name
+ *  upon handler connections and emissions.
+ * @G_SIGNAL_ACTION: Action signals are signals that may freely be emitted on alive
+ *  objects from user code via g_signal_emit() and friends, without
+ *  the need of being embedded into extra code that performs pre or
+ *  post emission adjustments on the object. They can also be thought
+ *  of as object methods which can be called generically by 
+ *  third-party code.
+ * @G_SIGNAL_NO_HOOKS: No emissions hooks are supported for this signal.
+ * @G_SIGNAL_MUST_COLLECT: Varargs signal emission will always collect the
+ *   arguments, even if there are no signal handlers connected.  Since 2.30.
+ * @G_SIGNAL_DEPRECATED: The signal is deprecated and will be removed
+ *   in a future version. A warning will be generated if it is connected while
+ *   running with G_ENABLE_DIAGNOSTIC=1.  Since 2.32.
+ * 
+ * The signal flags are used to specify a signal's behaviour, the overall
+ * signal description outlines how especially the RUN flags control the
+ * stages of a signal emission.
+ */
 typedef enum
 {
   G_SIGNAL_RUN_FIRST   = 1 << 0,
@@ -51,9 +132,44 @@ typedef enum
   G_SIGNAL_NO_RECURSE  = 1 << 3,
   G_SIGNAL_DETAILED    = 1 << 4,
   G_SIGNAL_ACTION      = 1 << 5,
-  G_SIGNAL_NO_HOOKS    = 1 << 6
-#define        G_SIGNAL_FLAGS_MASK  0x7f
+  G_SIGNAL_NO_HOOKS    = 1 << 6,
+  G_SIGNAL_MUST_COLLECT = 1 << 7,
+  G_SIGNAL_DEPRECATED   = 1 << 8
 } GSignalFlags;
+/**
+ * G_SIGNAL_FLAGS_MASK:
+ * 
+ * A mask for all #GSignalFlags bits.
+ */
+#define G_SIGNAL_FLAGS_MASK  0x1ff
+/**
+ * GConnectFlags:
+ * @G_CONNECT_AFTER: whether the handler should be called before or after the 
+ *  default handler of the signal.
+ * @G_CONNECT_SWAPPED: whether the instance and data should be swapped when
+ *  calling the handler; see g_signal_connect_swapped() for an example.
+ * 
+ * The connection flags are used to specify the behaviour of a signal's 
+ * connection.
+ */
+typedef enum
+{
+  G_CONNECT_AFTER      = 1 << 0,
+  G_CONNECT_SWAPPED    = 1 << 1
+} GConnectFlags;
+/**
+ * GSignalMatchType:
+ * @G_SIGNAL_MATCH_ID: The signal id must be equal.
+ * @G_SIGNAL_MATCH_DETAIL: The signal detail be equal.
+ * @G_SIGNAL_MATCH_CLOSURE: The closure must be the same.
+ * @G_SIGNAL_MATCH_FUNC: The C closure callback must be the same.
+ * @G_SIGNAL_MATCH_DATA: The closure data must be the same.
+ * @G_SIGNAL_MATCH_UNBLOCKED: Only unblocked signals may matched.
+ * 
+ * The match types specify what g_signal_handlers_block_matched(),
+ * g_signal_handlers_unblock_matched() and g_signal_handlers_disconnect_matched()
+ * match signals by.
+ */
 typedef enum
 {
   G_SIGNAL_MATCH_ID       = 1 << 0,
@@ -62,91 +178,427 @@ typedef enum
   G_SIGNAL_MATCH_FUNC     = 1 << 3,
   G_SIGNAL_MATCH_DATA     = 1 << 4,
   G_SIGNAL_MATCH_UNBLOCKED = 1 << 5
-#define        G_SIGNAL_MATCH_MASK  0x3f
 } GSignalMatchType;
+/**
+ * G_SIGNAL_MATCH_MASK:
+ * 
+ * A mask for all #GSignalMatchType bits.
+ */
+#define G_SIGNAL_MATCH_MASK  0x3f
+/**
+ * G_SIGNAL_TYPE_STATIC_SCOPE:
+ * 
+ * This macro flags signal argument types for which the signal system may 
+ * assume that instances thereof remain persistent across all signal emissions
+ * they are used in. This is only useful for non ref-counted, value-copy types.
+ * 
+ * To flag a signal argument in this way, add `| G_SIGNAL_TYPE_STATIC_SCOPE`
+ * to the corresponding argument of g_signal_new().
+ * |[
+ * g_signal_new ("size_request",
+ *   G_TYPE_FROM_CLASS (gobject_class),
+ *      G_SIGNAL_RUN_FIRST,
+ *      G_STRUCT_OFFSET (GtkWidgetClass, size_request),
+ *      NULL, NULL,
+ *      _gtk_marshal_VOID__BOXED,
+ *      G_TYPE_NONE, 1,
+ *      GTK_TYPE_REQUISITION | G_SIGNAL_TYPE_STATIC_SCOPE);
+ * ]|
+ */
+#define        G_SIGNAL_TYPE_STATIC_SCOPE (G_TYPE_FLAG_RESERVED_ID_BIT)
 
 
 /* --- signal information --- */
+/**
+ * GSignalInvocationHint:
+ * @signal_id: The signal id of the signal invoking the callback
+ * @detail: The detail passed on for this emission
+ * @run_type: The stage the signal emission is currently in, this
+ *  field will contain one of %G_SIGNAL_RUN_FIRST,
+ *  %G_SIGNAL_RUN_LAST or %G_SIGNAL_RUN_CLEANUP.
+ * 
+ * The #GSignalInvocationHint structure is used to pass on additional information
+ * to callbacks during a signal emission.
+ */
 struct _GSignalInvocationHint
 {
   guint                signal_id;
   GQuark       detail;
   GSignalFlags run_type;
 };
+/**
+ * GSignalQuery:
+ * @signal_id: The signal id of the signal being queried, or 0 if the
+ *  signal to be queried was unknown.
+ * @signal_name: The signal name.
+ * @itype: The interface/instance type that this signal can be emitted for.
+ * @signal_flags: The signal flags as passed in to g_signal_new().
+ * @return_type: The return type for user callbacks.
+ * @n_params: The number of parameters that user callbacks take.
+ * @param_types: (array length=n_params): The individual parameter types for
+ *  user callbacks, note that the effective callback signature is:
+ *  |[<!-- language="C" -->
+ *  @return_type callback (#gpointer     data1,
+ *  [param_types param_names,]
+ *  gpointer     data2);
+ *  ]|
+ * 
+ * A structure holding in-depth information for a specific signal. It is
+ * filled in by the g_signal_query() function.
+ */
 struct _GSignalQuery
 {
   guint                signal_id;
   const gchar  *signal_name;
   GType                itype;
   GSignalFlags signal_flags;
-  GType                return_type;
+  GType                return_type; /* mangled with G_SIGNAL_TYPE_STATIC_SCOPE flag */
   guint                n_params;
-  const GType  *param_types;
+  const GType  *param_types; /* mangled with G_SIGNAL_TYPE_STATIC_SCOPE flag */
 };
 
 
 /* --- signals --- */
-guint  g_signal_newv                   (const gchar            *signal_name,
-                                        GType                   itype,
-                                        GSignalFlags            signal_flags,
-                                        GClosure               *class_closure,
-                                        GSignalAccumulator      accumulator,
-                                        GSignalCMarshaller      c_marshaller,
-                                        GType                   return_type,
-                                        guint                   n_params,
-                                        GType                  *param_types);
-void   g_signal_emitv                  (const GValue           *instance_and_params,
-                                        guint                   signal_id,
-                                        GQuark                  detail,
-                                        GValue                 *return_value);
-guint  g_signal_lookup                 (const gchar            *name,
-                                        GType                   itype);
-gchar* g_signal_name                   (guint                   signal_id);
-void   g_signal_query                  (guint                   signal_id,
-                                        GSignalQuery           *query);
+GLIB_AVAILABLE_IN_ALL
+guint                 g_signal_newv         (const gchar        *signal_name,
+                                            GType               itype,
+                                            GSignalFlags        signal_flags,
+                                            GClosure           *class_closure,
+                                            GSignalAccumulator  accumulator,
+                                            gpointer            accu_data,
+                                            GSignalCMarshaller  c_marshaller,
+                                            GType               return_type,
+                                            guint               n_params,
+                                            GType              *param_types);
+GLIB_AVAILABLE_IN_ALL
+guint                 g_signal_new_valist   (const gchar        *signal_name,
+                                            GType               itype,
+                                            GSignalFlags        signal_flags,
+                                            GClosure           *class_closure,
+                                            GSignalAccumulator  accumulator,
+                                            gpointer            accu_data,
+                                            GSignalCMarshaller  c_marshaller,
+                                            GType               return_type,
+                                            guint               n_params,
+                                            va_list             args);
+GLIB_AVAILABLE_IN_ALL
+guint                 g_signal_new          (const gchar        *signal_name,
+                                            GType               itype,
+                                            GSignalFlags        signal_flags,
+                                            guint               class_offset,
+                                            GSignalAccumulator  accumulator,
+                                            gpointer            accu_data,
+                                            GSignalCMarshaller  c_marshaller,
+                                            GType               return_type,
+                                            guint               n_params,
+                                            ...);
+GLIB_AVAILABLE_IN_ALL
+guint            g_signal_new_class_handler (const gchar        *signal_name,
+                                             GType               itype,
+                                             GSignalFlags        signal_flags,
+                                             GCallback           class_handler,
+                                             GSignalAccumulator  accumulator,
+                                             gpointer            accu_data,
+                                             GSignalCMarshaller  c_marshaller,
+                                             GType               return_type,
+                                             guint               n_params,
+                                             ...);
+GLIB_AVAILABLE_IN_ALL
+void             g_signal_set_va_marshaller (guint              signal_id,
+                                            GType              instance_type,
+                                            GSignalCVaMarshaller va_marshaller);
+
+GLIB_AVAILABLE_IN_ALL
+void                  g_signal_emitv        (const GValue       *instance_and_params,
+                                            guint               signal_id,
+                                            GQuark              detail,
+                                            GValue             *return_value);
+GLIB_AVAILABLE_IN_ALL
+void                  g_signal_emit_valist  (gpointer            instance,
+                                            guint               signal_id,
+                                            GQuark              detail,
+                                            va_list             var_args);
+GLIB_AVAILABLE_IN_ALL
+void                  g_signal_emit         (gpointer            instance,
+                                            guint               signal_id,
+                                            GQuark              detail,
+                                            ...);
+GLIB_AVAILABLE_IN_ALL
+void                  g_signal_emit_by_name (gpointer            instance,
+                                            const gchar        *detailed_signal,
+                                            ...);
+GLIB_AVAILABLE_IN_ALL
+guint                 g_signal_lookup       (const gchar        *name,
+                                            GType               itype);
+GLIB_AVAILABLE_IN_ALL
+const gchar *         g_signal_name         (guint               signal_id);
+GLIB_AVAILABLE_IN_ALL
+void                  g_signal_query        (guint               signal_id,
+                                            GSignalQuery       *query);
+GLIB_AVAILABLE_IN_ALL
+guint*                g_signal_list_ids     (GType               itype,
+                                            guint              *n_ids);
+GLIB_AVAILABLE_IN_ALL
+gboolean             g_signal_parse_name   (const gchar        *detailed_signal,
+                                            GType               itype,
+                                            guint              *signal_id_p,
+                                            GQuark             *detail_p,
+                                            gboolean            force_detail_quark);
+GLIB_AVAILABLE_IN_ALL
+GSignalInvocationHint* g_signal_get_invocation_hint (gpointer    instance);
+
+
+/* --- signal emissions --- */
+GLIB_AVAILABLE_IN_ALL
+void   g_signal_stop_emission              (gpointer             instance,
+                                            guint                signal_id,
+                                            GQuark               detail);
+GLIB_AVAILABLE_IN_ALL
+void   g_signal_stop_emission_by_name      (gpointer             instance,
+                                            const gchar         *detailed_signal);
+GLIB_AVAILABLE_IN_ALL
+gulong g_signal_add_emission_hook          (guint                signal_id,
+                                            GQuark               detail,
+                                            GSignalEmissionHook  hook_func,
+                                            gpointer             hook_data,
+                                            GDestroyNotify       data_destroy);
+GLIB_AVAILABLE_IN_ALL
+void   g_signal_remove_emission_hook       (guint                signal_id,
+                                            gulong               hook_id);
 
 
 /* --- signal handlers --- */
-guint   g_signal_connect_closure       (gpointer                instance,
-                                        guint                   signal_id,
-                                        GQuark                  detail,
-                                        GClosure               *closure,
-                                        gboolean                after);
-void    g_signal_handler_disconnect    (gpointer                instance,
-                                        guint                   handler_id);
-void    g_signal_handler_block         (gpointer                instance,
-                                        guint                   handler_id);
-void    g_signal_handler_unblock       (gpointer                instance,
-                                        guint                   handler_id);
-guint   g_signal_handler_find          (gpointer                instance,
-                                        GSignalMatchType        mask,
-                                        guint                   signal_id,
-                                        GQuark                  detail,
-                                        GClosure               *closure,
-                                        gpointer                func,
-                                        gpointer                data);
-gboolean g_signal_has_handler_pending  (gpointer                instance,
-                                        guint                   signal_id,
-                                        GQuark                  detail,
-                                        gboolean                may_be_blocked);
+GLIB_AVAILABLE_IN_ALL
+gboolean g_signal_has_handler_pending        (gpointer           instance,
+                                              guint              signal_id,
+                                              GQuark             detail,
+                                              gboolean           may_be_blocked);
+GLIB_AVAILABLE_IN_ALL
+gulong  g_signal_connect_closure_by_id       (gpointer           instance,
+                                              guint              signal_id,
+                                              GQuark             detail,
+                                              GClosure          *closure,
+                                              gboolean           after);
+GLIB_AVAILABLE_IN_ALL
+gulong  g_signal_connect_closure             (gpointer           instance,
+                                              const gchar       *detailed_signal,
+                                              GClosure          *closure,
+                                              gboolean           after);
+GLIB_AVAILABLE_IN_ALL
+gulong  g_signal_connect_data                (gpointer           instance,
+                                              const gchar       *detailed_signal,
+                                              GCallback          c_handler,
+                                              gpointer           data,
+                                              GClosureNotify     destroy_data,
+                                              GConnectFlags      connect_flags);
+GLIB_AVAILABLE_IN_ALL
+void    g_signal_handler_block               (gpointer           instance,
+                                              gulong             handler_id);
+GLIB_AVAILABLE_IN_ALL
+void    g_signal_handler_unblock             (gpointer           instance,
+                                              gulong             handler_id);
+GLIB_AVAILABLE_IN_ALL
+void    g_signal_handler_disconnect          (gpointer           instance,
+                                              gulong             handler_id);
+GLIB_AVAILABLE_IN_ALL
+gboolean g_signal_handler_is_connected       (gpointer           instance,
+                                              gulong             handler_id);
+GLIB_AVAILABLE_IN_ALL
+gulong  g_signal_handler_find                (gpointer           instance,
+                                              GSignalMatchType   mask,
+                                              guint              signal_id,
+                                              GQuark             detail,
+                                              GClosure          *closure,
+                                              gpointer           func,
+                                              gpointer           data);
+GLIB_AVAILABLE_IN_ALL
+guint   g_signal_handlers_block_matched      (gpointer           instance,
+                                              GSignalMatchType   mask,
+                                              guint              signal_id,
+                                              GQuark             detail,
+                                              GClosure          *closure,
+                                              gpointer           func,
+                                              gpointer           data);
+GLIB_AVAILABLE_IN_ALL
+guint   g_signal_handlers_unblock_matched    (gpointer           instance,
+                                              GSignalMatchType   mask,
+                                              guint              signal_id,
+                                              GQuark             detail,
+                                              GClosure          *closure,
+                                              gpointer           func,
+                                              gpointer           data);
+GLIB_AVAILABLE_IN_ALL
+guint   g_signal_handlers_disconnect_matched (gpointer           instance,
+                                              GSignalMatchType   mask,
+                                              guint              signal_id,
+                                              GQuark             detail,
+                                              GClosure          *closure,
+                                              gpointer           func,
+                                              gpointer           data);
 
 
-/* --- signal emissions --- */
-void   g_signal_stop_emission          (gpointer                instance,
-                                        guint                   signal_id,
-                                        GQuark                  detail);
-guint  g_signal_add_emission_hook_full (guint                   signal_id,
-                                        GClosure               *closure);
-void   g_signal_remove_emission_hook   (guint                   signal_id,
-                                        guint                   hook_id);
+/* --- overriding and chaining --- */
+GLIB_AVAILABLE_IN_ALL
+void    g_signal_override_class_closure       (guint              signal_id,
+                                               GType              instance_type,
+                                               GClosure          *class_closure);
+GLIB_AVAILABLE_IN_ALL
+void    g_signal_override_class_handler       (const gchar       *signal_name,
+                                               GType              instance_type,
+                                               GCallback          class_handler);
+GLIB_AVAILABLE_IN_ALL
+void    g_signal_chain_from_overridden        (const GValue      *instance_and_params,
+                                               GValue            *return_value);
+GLIB_AVAILABLE_IN_ALL
+void   g_signal_chain_from_overridden_handler (gpointer           instance,
+                                               ...);
 
-/*< private >*/
-void   g_signal_handlers_destroy       (gpointer               instance);
-void   g_signals_destroy               (GType                  itype);
 
+/* --- convenience --- */
+/**
+ * g_signal_connect:
+ * @instance: the instance to connect to.
+ * @detailed_signal: a string of the form "signal-name::detail".
+ * @c_handler: the #GCallback to connect.
+ * @data: data to pass to @c_handler calls.
+ * 
+ * Connects a #GCallback function to a signal for a particular object.
+ * 
+ * The handler will be called before the default handler of the signal.
+ * 
+ * Returns: the handler id (always greater than 0 for successful connections)
+ */
+#define g_signal_connect(instance, detailed_signal, c_handler, data) \
+    g_signal_connect_data ((instance), (detailed_signal), (c_handler), (data), NULL, (GConnectFlags) 0)
+/**
+ * g_signal_connect_after:
+ * @instance: the instance to connect to.
+ * @detailed_signal: a string of the form "signal-name::detail".
+ * @c_handler: the #GCallback to connect.
+ * @data: data to pass to @c_handler calls.
+ * 
+ * Connects a #GCallback function to a signal for a particular object.
+ * 
+ * The handler will be called after the default handler of the signal.
+ * 
+ * Returns: the handler id (always greater than 0 for successful connections)
+ */
+#define g_signal_connect_after(instance, detailed_signal, c_handler, data) \
+    g_signal_connect_data ((instance), (detailed_signal), (c_handler), (data), NULL, G_CONNECT_AFTER)
+/**
+ * g_signal_connect_swapped:
+ * @instance: the instance to connect to.
+ * @detailed_signal: a string of the form "signal-name::detail".
+ * @c_handler: the #GCallback to connect.
+ * @data: data to pass to @c_handler calls.
+ * 
+ * Connects a #GCallback function to a signal for a particular object.
+ * 
+ * The instance on which the signal is emitted and @data will be swapped when 
+ * calling the handler. This is useful when calling pre-existing functions to
+ * operate purely on the @data, rather than the @instance: swapping the
+ * parameters avoids the need to write a wrapper function.
+ *
+ * For example, this allows the shorter code:
+ * |[<!-- language="C" -->
+ * g_signal_connect_swapped (button, "clicked",
+ *                           (GCallback) gtk_widget_hide, other_widget);
+ * ]|
+ *
+ * Rather than the cumbersome:
+ * |[<!-- language="C" -->
+ * static void
+ * button_clicked_cb (GtkButton *button, GtkWidget *other_widget)
+ * {
+ *     gtk_widget_hide (other_widget);
+ * }
+ *
+ * …
+ *
+ * g_signal_connect (button, "clicked",
+ *                   (GCallback) button_clicked_cb, other_widget);
+ * ]|
+ * 
+ * Returns: the handler ID (always greater than 0 for successful connections)
+ */
+#define g_signal_connect_swapped(instance, detailed_signal, c_handler, data) \
+    g_signal_connect_data ((instance), (detailed_signal), (c_handler), (data), NULL, G_CONNECT_SWAPPED)
+/**
+ * g_signal_handlers_disconnect_by_func:
+ * @instance: The instance to remove handlers from.
+ * @func: The C closure callback of the handlers (useless for non-C closures).
+ * @data: The closure data of the handlers' closures.
+ * 
+ * Disconnects all handlers on an instance that match @func and @data.
+ * 
+ * Returns: The number of handlers that matched.
+ */
+#define        g_signal_handlers_disconnect_by_func(instance, func, data)                                              \
+    g_signal_handlers_disconnect_matched ((instance),                                                          \
+                                         (GSignalMatchType) (G_SIGNAL_MATCH_FUNC | G_SIGNAL_MATCH_DATA),       \
+                                         0, 0, NULL, (func), (data))
+
+/**
+ * g_signal_handlers_disconnect_by_data:
+ * @instance: The instance to remove handlers from
+ * @data: the closure data of the handlers' closures
+ *
+ * Disconnects all handlers on an instance that match @data.
+ *
+ * Returns: The number of handlers that matched.
+ *
+ * Since: 2.32
+ */
+#define g_signal_handlers_disconnect_by_data(instance, data) \
+  g_signal_handlers_disconnect_matched ((instance), G_SIGNAL_MATCH_DATA, 0, 0, NULL, NULL, (data))
+
+/**
+ * g_signal_handlers_block_by_func:
+ * @instance: The instance to block handlers from.
+ * @func: The C closure callback of the handlers (useless for non-C closures).
+ * @data: The closure data of the handlers' closures.
+ * 
+ * Blocks all handlers on an instance that match @func and @data.
+ * 
+ * Returns: The number of handlers that matched.
+ */
+#define        g_signal_handlers_block_by_func(instance, func, data)                                                   \
+    g_signal_handlers_block_matched      ((instance),                                                          \
+                                         (GSignalMatchType) (G_SIGNAL_MATCH_FUNC | G_SIGNAL_MATCH_DATA),       \
+                                         0, 0, NULL, (func), (data))
+/**
+ * g_signal_handlers_unblock_by_func:
+ * @instance: The instance to unblock handlers from.
+ * @func: The C closure callback of the handlers (useless for non-C closures).
+ * @data: The closure data of the handlers' closures.
+ * 
+ * Unblocks all handlers on an instance that match @func and @data.
+ * 
+ * Returns: The number of handlers that matched.
+ */
+#define        g_signal_handlers_unblock_by_func(instance, func, data)                                                 \
+    g_signal_handlers_unblock_matched    ((instance),                                                          \
+                                         (GSignalMatchType) (G_SIGNAL_MATCH_FUNC | G_SIGNAL_MATCH_DATA),       \
+                                         0, 0, NULL, (func), (data))
+
+
+GLIB_AVAILABLE_IN_ALL
+gboolean g_signal_accumulator_true_handled (GSignalInvocationHint *ihint,
+                                           GValue                *return_accu,
+                                           const GValue          *handler_return,
+                                           gpointer               dummy);
+
+GLIB_AVAILABLE_IN_ALL
+gboolean g_signal_accumulator_first_wins   (GSignalInvocationHint *ihint,
+                                            GValue                *return_accu,
+                                            const GValue          *handler_return,
+                                            gpointer               dummy);
+
+/*< private >*/
+GLIB_AVAILABLE_IN_ALL
+void    g_signal_handlers_destroy            (gpointer           instance);
+void    _g_signals_destroy                   (GType              itype);
 
-#ifdef __cplusplus
-}
-#endif /* __cplusplus */
+G_END_DECLS
 
 #endif /* __G_SIGNAL_H__ */