1 /* GObject - GLib Type, Object, Parameter and Signal Library
2 * Copyright (C) 2000-2001 Red Hat, Inc.
3 * Copyright (C) 2005 Imendio AB
5 * This library is free software; you can redistribute it and/or
6 * modify it under the terms of the GNU Lesser General Public
7 * License as published by the Free Software Foundation; either
8 * version 2 of the License, or (at your option) any later version.
10 * This library is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
13 * Lesser General Public License for more details.
15 * You should have received a copy of the GNU Lesser General
16 * Public License along with this library; if not, write to the
17 * Free Software Foundation, Inc., 59 Temple Place, Suite 330,
18 * Boston, MA 02111-1307, USA.
20 #if !defined (__GLIB_GOBJECT_H_INSIDE__) && !defined (GOBJECT_COMPILATION)
21 #error "Only <glib-object.h> can be included directly."
24 #ifndef __G_CLOSURE_H__
25 #define __G_CLOSURE_H__
27 #include <gobject/gtype.h>
33 * G_CLOSURE_NEEDS_MARSHAL:
34 * @closure: a #GClosure
36 * Check if the closure still needs a marshaller. See g_closure_set_marshal().
38 * Returns: %TRUE if a #GClosureMarshal marshaller has not yet been set on
41 #define G_CLOSURE_NEEDS_MARSHAL(closure) (((GClosure*) (closure))->marshal == NULL)
43 * G_CLOSURE_N_NOTIFIERS:
46 * Get the total number of notifiers connected with the closure @cl.
47 * The count includes the meta marshaller, the finalize and invalidate notifiers
48 * and the marshal guards. Note that each guard counts as two notifiers.
49 * See g_closure_set_meta_marshal(), g_closure_add_finalize_notifier(),
50 * g_closure_add_invalidate_notifier() and g_closure_add_marshal_guards().
52 * Returns: number of notifiers
54 #define G_CLOSURE_N_NOTIFIERS(cl) ((cl)->meta_marshal + ((cl)->n_guards << 1L) + \
55 (cl)->n_fnotifiers + (cl)->n_inotifiers)
57 * G_CCLOSURE_SWAP_DATA:
58 * @cclosure: a #GCClosure
60 * Checks whether the user data of the #GCClosure should be passed as the
61 * first parameter to the callback. See g_cclosure_new_swap().
63 * Returns: %TRUE if data has to be swapped.
65 #define G_CCLOSURE_SWAP_DATA(cclosure) (((GClosure*) (cclosure))->derivative_flag)
68 * @f: a function pointer.
70 * Cast a function pointer to a #GCallback.
72 #define G_CALLBACK(f) ((GCallback) (f))
76 typedef struct _GClosure GClosure;
77 typedef struct _GClosureNotifyData GClosureNotifyData;
82 * The type used for callback functions in structure definitions and function
83 * signatures. This doesn't mean that all callback functions must take no
84 * parameters and return void. The required signature of a callback function
85 * is determined by the context in which is used (e.g. the signal to which it
86 * is connected). Use G_CALLBACK() to cast the callback function to a #GCallback.
88 typedef void (*GCallback) (void);
91 * @data: data specified when registering the notification callback
92 * @closure: the #GClosure on which the notification is emitted
94 * The type used for the various notification callbacks which can be registered
97 typedef void (*GClosureNotify) (gpointer data,
101 * @closure: the #GClosure to which the marshaller belongs
102 * @return_value: (allow-none): a #GValue to store the return
103 * value. May be %NULL if the callback of @closure doesn't return a
105 * @n_param_values: the length of the @param_values array
106 * @param_values: (array length=n_param_values): an array of
107 * #GValue<!-- -->s holding the arguments on which to invoke the
108 * callback of @closure
109 * @invocation_hint: (allow-none): the invocation hint given as the
110 * last argument to g_closure_invoke()
111 * @marshal_data: (allow-none): additional data specified when
112 * registering the marshaller, see g_closure_set_marshal() and
113 * g_closure_set_meta_marshal()
115 * The type used for marshaller functions.
117 typedef void (*GClosureMarshal) (GClosure *closure,
118 GValue *return_value,
119 guint n_param_values,
120 const GValue *param_values,
121 gpointer invocation_hint,
122 gpointer marshal_data);
125 * @closure: the #GClosure
126 * @callback: the callback function
128 * A #GCClosure is a specialization of #GClosure for C function callbacks.
130 typedef struct _GCClosure GCClosure;
133 /* --- structures --- */
134 struct _GClosureNotifyData
137 GClosureNotify notify;
141 * @in_marshal: Indicates whether the closure is currently being invoked with
143 * @is_invalid: Indicates whether the closure has been invalidated by
144 * g_closure_invalidate()
146 * A #GClosure represents a callback supplied by the programmer.
151 volatile guint ref_count : 15;
152 volatile guint meta_marshal : 1;
153 volatile guint n_guards : 1;
154 volatile guint n_fnotifiers : 2; /* finalization notifiers */
155 volatile guint n_inotifiers : 8; /* invalidation notifiers */
156 volatile guint in_inotify : 1;
157 volatile guint floating : 1;
159 volatile guint derivative_flag : 1;
161 volatile guint in_marshal : 1;
162 volatile guint is_invalid : 1;
164 /*< private >*/ void (*marshal) (GClosure *closure,
165 GValue /*out*/ *return_value,
166 guint n_param_values,
167 const GValue *param_values,
168 gpointer invocation_hint,
169 gpointer marshal_data);
170 /*< protected >*/ gpointer data;
172 /*< private >*/ GClosureNotifyData *notifiers;
174 /* invariants/constrains:
175 * - ->marshal and ->data are _invalid_ as soon as ->is_invalid==TRUE
176 * - invocation of all inotifiers occours prior to fnotifiers
177 * - order of inotifiers is random
178 * inotifiers may _not_ free/invalidate parameter values (e.g. ->data)
179 * - order of fnotifiers is random
180 * - each notifier may only be removed before or during its invocation
181 * - reference counting may only happen prior to fnotify invocation
182 * (in that sense, fnotifiers are really finalization handlers)
185 /* closure for C function calls, callback() is the user function
194 /* --- prototypes --- */
195 GClosure* g_cclosure_new (GCallback callback_func,
197 GClosureNotify destroy_data);
198 GClosure* g_cclosure_new_swap (GCallback callback_func,
200 GClosureNotify destroy_data);
201 GClosure* g_signal_type_cclosure_new (GType itype,
202 guint struct_offset);
205 /* --- prototypes --- */
206 GClosure* g_closure_ref (GClosure *closure);
207 void g_closure_sink (GClosure *closure);
208 void g_closure_unref (GClosure *closure);
210 GClosure* g_closure_new_simple (guint sizeof_closure,
212 void g_closure_add_finalize_notifier (GClosure *closure,
213 gpointer notify_data,
214 GClosureNotify notify_func);
215 void g_closure_remove_finalize_notifier (GClosure *closure,
216 gpointer notify_data,
217 GClosureNotify notify_func);
218 void g_closure_add_invalidate_notifier (GClosure *closure,
219 gpointer notify_data,
220 GClosureNotify notify_func);
221 void g_closure_remove_invalidate_notifier (GClosure *closure,
222 gpointer notify_data,
223 GClosureNotify notify_func);
224 void g_closure_add_marshal_guards (GClosure *closure,
225 gpointer pre_marshal_data,
226 GClosureNotify pre_marshal_notify,
227 gpointer post_marshal_data,
228 GClosureNotify post_marshal_notify);
229 void g_closure_set_marshal (GClosure *closure,
230 GClosureMarshal marshal);
231 void g_closure_set_meta_marshal (GClosure *closure,
232 gpointer marshal_data,
233 GClosureMarshal meta_marshal);
234 void g_closure_invalidate (GClosure *closure);
235 void g_closure_invoke (GClosure *closure,
236 GValue /*out*/ *return_value,
237 guint n_param_values,
238 const GValue *param_values,
239 gpointer invocation_hint);
242 OK: data_object::destroy -> closure_invalidate();
243 MIS: closure_invalidate() -> disconnect(closure);
244 MIS: disconnect(closure) -> (unlink) closure_unref();
245 OK: closure_finalize() -> g_free (data_string);
248 - need marshaller repo with decent aliasing to base types
249 - provide marshaller collection, virtually covering anything out there
252 void g_cclosure_marshal_generic (GClosure *closure,
253 GValue *return_gvalue,
254 guint n_param_values,
255 const GValue *param_values,
256 gpointer invocation_hint,
257 gpointer marshal_data);
261 #endif /* __G_CLOSURE_H__ */