/* GObject - GLib Type, Object, Parameter and Signal Library
* Copyright (C) 2000-2001 Red Hat, Inc.
* Copyright (C) 2005 Imendio AB
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* 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
* 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, see <http://www.gnu.org/licenses/>.
*/
#ifndef __G_CLOSURE_H__
#define __G_CLOSURE_H__
#if !defined (__GLIB_GOBJECT_H_INSIDE__) && !defined (GOBJECT_COMPILATION)
#error "Only <glib-object.h> can be included directly."
#endif
#include <gobject/gtype.h>
G_BEGIN_DECLS
/* --- defines --- */
/**
* G_CLOSURE_NEEDS_MARSHAL:
* @closure: a #GClosure
*
* Check if the closure still needs a marshaller. See g_closure_set_marshal().
*
* Returns: %TRUE if a #GClosureMarshal marshaller has not yet been set on
* @closure.
*/
#define G_CLOSURE_NEEDS_MARSHAL(closure) (((GClosure*) (closure))->marshal == NULL)
/**
* G_CLOSURE_N_NOTIFIERS:
* @cl: a #GClosure
*
* Get the total number of notifiers connected with the closure @cl.
* The count includes the meta marshaller, the finalize and invalidate notifiers
* and the marshal guards. Note that each guard counts as two notifiers.
* See g_closure_set_meta_marshal(), g_closure_add_finalize_notifier(),
* g_closure_add_invalidate_notifier() and g_closure_add_marshal_guards().
*
* Returns: number of notifiers
*/
#define G_CLOSURE_N_NOTIFIERS(cl) (((cl)->n_guards << 1L) + \
(cl)->n_fnotifiers + (cl)->n_inotifiers)
/**
* G_CCLOSURE_SWAP_DATA:
* @cclosure: a #GCClosure
*
* Checks whether the user data of the #GCClosure should be passed as the
* first parameter to the callback. See g_cclosure_new_swap().
*
* Returns: %TRUE if data has to be swapped.
*/
#define G_CCLOSURE_SWAP_DATA(cclosure) (((GClosure*) (cclosure))->derivative_flag)
/**
* G_CALLBACK:
* @f: a function pointer.
*
* Cast a function pointer to a #GCallback.
*/
#define G_CALLBACK(f) ((GCallback) (f))
/* -- typedefs --- */
typedef struct _GClosure GClosure;
typedef struct _GClosureNotifyData GClosureNotifyData;
/**
* GCallback:
*
* The type used for callback functions in structure definitions and function
* signatures. This doesn't mean that all callback functions must take no
* parameters and return void. The required signature of a callback function
* is determined by the context in which is used (e.g. the signal to which it
* is connected). Use G_CALLBACK() to cast the callback function to a #GCallback.
*/
typedef void (*GCallback) (void);
/**
* GClosureNotify:
* @data: data specified when registering the notification callback
* @closure: the #GClosure on which the notification is emitted
*
* The type used for the various notification callbacks which can be registered
* on closures.
*/
typedef void (*GClosureNotify) (gpointer data,
GClosure *closure);
/**
* GClosureMarshal:
* @closure: the #GClosure to which the marshaller belongs
* @return_value: (nullable): a #GValue to store the return
* value. May be %NULL if the callback of @closure doesn't return a
* value.
* @n_param_values: the length of the @param_values array
* @param_values: (array length=n_param_values): an array of
* #GValues holding the arguments on which to invoke the
* callback of @closure
* @invocation_hint: (nullable): the invocation hint given as the
* last argument to g_closure_invoke()
* @marshal_data: (nullable): additional data specified when
* registering the marshaller, see g_closure_set_marshal() and
* g_closure_set_meta_marshal()
*
* The type used for marshaller functions.
*/
typedef void (*GClosureMarshal) (GClosure *closure,
GValue *return_value,
guint n_param_values,
const GValue *param_values,
gpointer invocation_hint,
gpointer marshal_data);
/**
* GVaClosureMarshal:
* @closure: the #GClosure to which the marshaller belongs
* @return_value: (nullable): a #GValue to store the return
* value. May be %NULL if the callback of @closure doesn't return a
* value.
* @instance: (type GObject.TypeInstance): the instance on which the closure is
* invoked.
* @args: va_list of arguments to be passed to the closure.
* @marshal_data: (nullable): additional data specified when
* registering the marshaller, see g_closure_set_marshal() and
* g_closure_set_meta_marshal()
* @n_params: the length of the @param_types array
* @param_types: (array length=n_params): the #GType of each argument from
* @args.
*
* 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 void (* GVaClosureMarshal) (GClosure *closure,
GValue *return_value,
gpointer instance,
va_list args,
gpointer marshal_data,
int n_params,
GType *param_types);
/**
* GCClosure:
* @closure: the #GClosure
* @callback: the callback function
*
* A #GCClosure is a specialization of #GClosure for C function callbacks.
*/
typedef struct _GCClosure GCClosure;
/* --- structures --- */
struct _GClosureNotifyData
{
gpointer data;
GClosureNotify notify;
};
/**
* GClosure:
* @in_marshal: Indicates whether the closure is currently being invoked with
* g_closure_invoke()
* @is_invalid: Indicates whether the closure has been invalidated by
* g_closure_invalidate()
*
* A #GClosure represents a callback supplied by the programmer.
*/
struct _GClosure
{
/*< private >*/
volatile guint ref_count : 15;
/* meta_marshal is not used anymore but must be zero for historical reasons
as it was exposed in the G_CLOSURE_N_NOTIFIERS macro */
volatile guint meta_marshal_nouse : 1;
volatile guint n_guards : 1;
volatile guint n_fnotifiers : 2; /* finalization notifiers */
volatile guint n_inotifiers : 8; /* invalidation notifiers */
volatile guint in_inotify : 1;
volatile guint floating : 1;
/*< protected >*/
volatile guint derivative_flag : 1;
/*< public >*/
volatile guint in_marshal : 1;
volatile guint is_invalid : 1;
/*< private >*/ void (*marshal) (GClosure *closure,
GValue /*out*/ *return_value,
guint n_param_values,
const GValue *param_values,
gpointer invocation_hint,
gpointer marshal_data);
/*< protected >*/ gpointer data;
/*< private >*/ GClosureNotifyData *notifiers;
/* invariants/constrains:
* - ->marshal and ->data are _invalid_ as soon as ->is_invalid==TRUE
* - invocation of all inotifiers occours prior to fnotifiers
* - order of inotifiers is random
* inotifiers may _not_ free/invalidate parameter values (e.g. ->data)
* - order of fnotifiers is random
* - each notifier may only be removed before or during its invocation
* - reference counting may only happen prior to fnotify invocation
* (in that sense, fnotifiers are really finalization handlers)
*/
};
/* closure for C function calls, callback() is the user function
*/
struct _GCClosure
{
GClosure closure;
gpointer callback;
};
/* --- prototypes --- */
GLIB_AVAILABLE_IN_ALL
GClosure* g_cclosure_new (GCallback callback_func,
gpointer user_data,
GClosureNotify destroy_data);
GLIB_AVAILABLE_IN_ALL
GClosure* g_cclosure_new_swap (GCallback callback_func,
gpointer user_data,
GClosureNotify destroy_data);
GLIB_AVAILABLE_IN_ALL
GClosure* g_signal_type_cclosure_new (GType itype,
guint struct_offset);
/* --- prototypes --- */
GLIB_AVAILABLE_IN_ALL
GClosure* g_closure_ref (GClosure *closure);
GLIB_AVAILABLE_IN_ALL
void g_closure_sink (GClosure *closure);
GLIB_AVAILABLE_IN_ALL
void g_closure_unref (GClosure *closure);
/* intimidating */
GLIB_AVAILABLE_IN_ALL
GClosure* g_closure_new_simple (guint sizeof_closure,
gpointer data);
GLIB_AVAILABLE_IN_ALL
void g_closure_add_finalize_notifier (GClosure *closure,
gpointer notify_data,
GClosureNotify notify_func);
GLIB_AVAILABLE_IN_ALL
void g_closure_remove_finalize_notifier (GClosure *closure,
gpointer notify_data,
GClosureNotify notify_func);
GLIB_AVAILABLE_IN_ALL
void g_closure_add_invalidate_notifier (GClosure *closure,
gpointer notify_data,
GClosureNotify notify_func);
GLIB_AVAILABLE_IN_ALL
void g_closure_remove_invalidate_notifier (GClosure *closure,
gpointer notify_data,
GClosureNotify notify_func);
GLIB_AVAILABLE_IN_ALL
void g_closure_add_marshal_guards (GClosure *closure,
gpointer pre_marshal_data,
GClosureNotify pre_marshal_notify,
gpointer post_marshal_data,
GClosureNotify post_marshal_notify);
GLIB_AVAILABLE_IN_ALL
void g_closure_set_marshal (GClosure *closure,
GClosureMarshal marshal);
GLIB_AVAILABLE_IN_ALL
void g_closure_set_meta_marshal (GClosure *closure,
gpointer marshal_data,
GClosureMarshal meta_marshal);
GLIB_AVAILABLE_IN_ALL
void g_closure_invalidate (GClosure *closure);
GLIB_AVAILABLE_IN_ALL
void g_closure_invoke (GClosure *closure,
GValue /*out*/ *return_value,
guint n_param_values,
const GValue *param_values,
gpointer invocation_hint);
/* FIXME:
OK: data_object::destroy -> closure_invalidate();
MIS: closure_invalidate() -> disconnect(closure);
MIS: disconnect(closure) -> (unlink) closure_unref();
OK: closure_finalize() -> g_free (data_string);
random remarks:
- need marshaller repo with decent aliasing to base types
- provide marshaller collection, virtually covering anything out there
*/
GLIB_AVAILABLE_IN_ALL
void g_cclosure_marshal_generic (GClosure *closure,
GValue *return_gvalue,
guint n_param_values,
const GValue *param_values,
gpointer invocation_hint,
gpointer marshal_data);
GLIB_AVAILABLE_IN_ALL
void g_cclosure_marshal_generic_va (GClosure *closure,
GValue *return_value,
gpointer instance,
va_list args_list,
gpointer marshal_data,
int n_params,
GType *param_types);
G_END_DECLS
#endif /* __G_CLOSURE_H__ */