/* 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 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, write to the * Free Software Foundation, Inc., 59 Temple Place, Suite 330, * Boston, MA 02111-1307, USA. */ /* * MT safe with regards to reference counting. */ #include "config.h" #include #include #include "gclosure.h" #include "gboxed.h" #include "gobject.h" #include "genums.h" #include "gvalue.h" #include "gvaluetypes.h" /** * SECTION:gclosure * @short_description: Functions as first-class objects * @title: Closures * * A #GClosure represents a callback supplied by the programmer. It * will generally comprise a function of some kind and a marshaller * used to call it. It is the reponsibility of the marshaller to * convert the arguments for the invocation from #GValues into * a suitable form, perform the callback on the converted arguments, * and transform the return value back into a #GValue. * * In the case of C programs, a closure usually just holds a pointer * to a function and maybe a data argument, and the marshaller * converts between #GValue and native C types. The GObject * library provides the #GCClosure type for this purpose. Bindings for * other languages need marshallers which convert between #GValues and suitable representations in the runtime of the language in * order to use functions written in that languages as callbacks. * * Within GObject, closures play an important role in the * implementation of signals. When a signal is registered, the * @c_marshaller argument to g_signal_new() specifies the default C * marshaller for any closure which is connected to this * signal. GObject provides a number of C marshallers for this * purpose, see the g_cclosure_marshal_*() functions. Additional C * marshallers can be generated with the glib-genmarshal utility. Closures * can be explicitly connected to signals with * g_signal_connect_closure(), but it usually more convenient to let * GObject create a closure automatically by using one of the * g_signal_connect_*() functions which take a callback function/user * data pair. * * Using closures has a number of important advantages over a simple * callback function/data pointer combination: * * * Closures allow the callee to get the types of the callback parameters, * which means that language bindings don't have to write individual glue * for each callback type. * * * The reference counting of #GClosure makes it easy to handle reentrancy * right; if a callback is removed while it is being invoked, the closure * and its parameters won't be freed until the invocation finishes. * * * g_closure_invalidate() and invalidation notifiers allow callbacks to be * automatically removed when the objects they point to go away. * * */ #define CLOSURE_MAX_REF_COUNT ((1 << 15) - 1) #define CLOSURE_MAX_N_GUARDS ((1 << 1) - 1) #define CLOSURE_MAX_N_FNOTIFIERS ((1 << 2) - 1) #define CLOSURE_MAX_N_INOTIFIERS ((1 << 8) - 1) #define CLOSURE_N_MFUNCS(cl) ((cl)->meta_marshal + \ ((cl)->n_guards << 1L)) /* same as G_CLOSURE_N_NOTIFIERS() (keep in sync) */ #define CLOSURE_N_NOTIFIERS(cl) (CLOSURE_N_MFUNCS (cl) + \ (cl)->n_fnotifiers + \ (cl)->n_inotifiers) typedef union { GClosure closure; volatile gint vint; } ClosureInt; #define CHANGE_FIELD(_closure, _field, _OP, _value, _must_set, _SET_OLD, _SET_NEW) \ G_STMT_START { \ ClosureInt *cunion = (ClosureInt*) _closure; \ gint new_int, old_int, success; \ do \ { \ ClosureInt tmp; \ tmp.vint = old_int = cunion->vint; \ _SET_OLD tmp.closure._field; \ tmp.closure._field _OP _value; \ _SET_NEW tmp.closure._field; \ new_int = tmp.vint; \ success = g_atomic_int_compare_and_exchange (&cunion->vint, old_int, new_int); \ } \ while (!success && _must_set); \ } G_STMT_END #define SWAP(_closure, _field, _value, _oldv) CHANGE_FIELD (_closure, _field, =, _value, TRUE, *(_oldv) =, (void) ) #define SET(_closure, _field, _value) CHANGE_FIELD (_closure, _field, =, _value, TRUE, (void), (void) ) #define INC(_closure, _field) CHANGE_FIELD (_closure, _field, +=, 1, TRUE, (void), (void) ) #define INC_ASSIGN(_closure, _field, _newv) CHANGE_FIELD (_closure, _field, +=, 1, TRUE, (void), *(_newv) = ) #define DEC(_closure, _field) CHANGE_FIELD (_closure, _field, -=, 1, TRUE, (void), (void) ) #define DEC_ASSIGN(_closure, _field, _newv) CHANGE_FIELD (_closure, _field, -=, 1, TRUE, (void), *(_newv) = ) #if 0 /* for non-thread-safe closures */ #define SWAP(cl,f,v,o) (void) (*(o) = cl->f, cl->f = v) #define SET(cl,f,v) (void) (cl->f = v) #define INC(cl,f) (void) (cl->f += 1) #define INC_ASSIGN(cl,f,n) (void) (cl->f += 1, *(n) = cl->f) #define DEC(cl,f) (void) (cl->f -= 1) #define DEC_ASSIGN(cl,f,n) (void) (cl->f -= 1, *(n) = cl->f) #endif enum { FNOTIFY, INOTIFY, PRE_NOTIFY, POST_NOTIFY }; /* --- functions --- */ /** * g_closure_new_simple: * @sizeof_closure: the size of the structure to allocate, must be at least * sizeof (GClosure) * @data: data to store in the @data field of the newly allocated #GClosure * * Allocates a struct of the given size and initializes the initial * part as a #GClosure. This function is mainly useful when * implementing new types of closures. * * |[ * typedef struct _MyClosure MyClosure; * struct _MyClosure * { * GClosure closure; * // extra data goes here * }; * * static void * my_closure_finalize (gpointer notify_data, * GClosure *closure) * { * MyClosure *my_closure = (MyClosure *)closure; * * // free extra data here * } * * MyClosure *my_closure_new (gpointer data) * { * GClosure *closure; * MyClosure *my_closure; * * closure = g_closure_new_simple (sizeof (MyClosure), data); * my_closure = (MyClosure *) closure; * * // initialize extra data here * * g_closure_add_finalize_notifier (closure, notify_data, * my_closure_finalize); * return my_closure; * } * ]| * * Returns: (transfer full): a newly allocated #GClosure */ GClosure* g_closure_new_simple (guint sizeof_closure, gpointer data) { GClosure *closure; g_return_val_if_fail (sizeof_closure >= sizeof (GClosure), NULL); closure = g_malloc0 (sizeof_closure); SET (closure, ref_count, 1); SET (closure, meta_marshal, 0); SET (closure, n_guards, 0); SET (closure, n_fnotifiers, 0); SET (closure, n_inotifiers, 0); SET (closure, in_inotify, FALSE); SET (closure, floating, TRUE); SET (closure, derivative_flag, 0); SET (closure, in_marshal, FALSE); SET (closure, is_invalid, FALSE); closure->marshal = NULL; closure->data = data; closure->notifiers = NULL; memset (G_STRUCT_MEMBER_P (closure, sizeof (*closure)), 0, sizeof_closure - sizeof (*closure)); return closure; } static inline void closure_invoke_notifiers (GClosure *closure, guint notify_type) { /* notifier layout: * meta_marshal n_guards n_guards n_fnotif. n_inotifiers * ->[[meta_marshal][pre_guards][post_guards][fnotifiers][inotifiers]] * * CLOSURE_N_MFUNCS(cl) = meta_marshal + n_guards + n_guards; * CLOSURE_N_NOTIFIERS(cl) = CLOSURE_N_MFUNCS(cl) + n_fnotifiers + n_inotifiers * * constrains/catches: * - closure->notifiers may be reloacted during callback * - closure->n_fnotifiers and closure->n_inotifiers may change during callback * - i.e. callbacks can be removed/added during invocation * - must prepare for callback removal during FNOTIFY and INOTIFY (done via ->marshal= & ->data=) * - must distinguish (->marshal= & ->data=) for INOTIFY vs. FNOTIFY (via ->in_inotify) * + closure->n_guards is const during PRE_NOTIFY & POST_NOTIFY * + closure->meta_marshal is const for all cases * + none of the callbacks can cause recursion * + closure->n_inotifiers is const 0 during FNOTIFY */ switch (notify_type) { GClosureNotifyData *ndata; guint i, offs; case FNOTIFY: while (closure->n_fnotifiers) { guint n; DEC_ASSIGN (closure, n_fnotifiers, &n); ndata = closure->notifiers + CLOSURE_N_MFUNCS (closure) + n; closure->marshal = (GClosureMarshal) ndata->notify; closure->data = ndata->data; ndata->notify (ndata->data, closure); } closure->marshal = NULL; closure->data = NULL; break; case INOTIFY: SET (closure, in_inotify, TRUE); while (closure->n_inotifiers) { guint n; DEC_ASSIGN (closure, n_inotifiers, &n); ndata = closure->notifiers + CLOSURE_N_MFUNCS (closure) + closure->n_fnotifiers + n; closure->marshal = (GClosureMarshal) ndata->notify; closure->data = ndata->data; ndata->notify (ndata->data, closure); } closure->marshal = NULL; closure->data = NULL; SET (closure, in_inotify, FALSE); break; case PRE_NOTIFY: i = closure->n_guards; offs = closure->meta_marshal; while (i--) { ndata = closure->notifiers + offs + i; ndata->notify (ndata->data, closure); } break; case POST_NOTIFY: i = closure->n_guards; offs = closure->meta_marshal + i; while (i--) { ndata = closure->notifiers + offs + i; ndata->notify (ndata->data, closure); } break; } } /** * g_closure_set_meta_marshal: (skip) * @closure: a #GClosure * @marshal_data: context-dependent data to pass to @meta_marshal * @meta_marshal: a #GClosureMarshal function * * Sets the meta marshaller of @closure. A meta marshaller wraps * @closure->marshal and modifies the way it is called in some * fashion. The most common use of this facility is for C callbacks. * The same marshallers (generated by glib-genmarshal) are used * everywhere, but the way that we get the callback function * differs. In most cases we want to use @closure->callback, but in * other cases we want to use some different technique to retrieve the * callback function. * * For example, class closures for signals (see * g_signal_type_cclosure_new()) retrieve the callback function from a * fixed offset in the class structure. The meta marshaller retrieves * the right callback and passes it to the marshaller as the * @marshal_data argument. */ void g_closure_set_meta_marshal (GClosure *closure, gpointer marshal_data, GClosureMarshal meta_marshal) { GClosureNotifyData *notifiers; g_return_if_fail (closure != NULL); g_return_if_fail (meta_marshal != NULL); g_return_if_fail (closure->is_invalid == FALSE); g_return_if_fail (closure->in_marshal == FALSE); g_return_if_fail (closure->meta_marshal == 0); notifiers = closure->notifiers; closure->notifiers = g_renew (GClosureNotifyData, NULL, CLOSURE_N_NOTIFIERS (closure) + 1); if (notifiers) { /* usually the meta marshal will be setup right after creation, so the * g_memmove() should be rare-case scenario */ g_memmove (closure->notifiers + 1, notifiers, CLOSURE_N_NOTIFIERS (closure) * sizeof (notifiers[0])); g_free (notifiers); } closure->notifiers[0].data = marshal_data; closure->notifiers[0].notify = (GClosureNotify) meta_marshal; SET (closure, meta_marshal, 1); } /** * g_closure_add_marshal_guards: (skip) * @closure: a #GClosure * @pre_marshal_data: data to pass to @pre_marshal_notify * @pre_marshal_notify: a function to call before the closure callback * @post_marshal_data: data to pass to @post_marshal_notify * @post_marshal_notify: a function to call after the closure callback * * Adds a pair of notifiers which get invoked before and after the * closure callback, respectively. This is typically used to protect * the extra arguments for the duration of the callback. See * g_object_watch_closure() for an example of marshal guards. */ void g_closure_add_marshal_guards (GClosure *closure, gpointer pre_marshal_data, GClosureNotify pre_marshal_notify, gpointer post_marshal_data, GClosureNotify post_marshal_notify) { guint i; g_return_if_fail (closure != NULL); g_return_if_fail (pre_marshal_notify != NULL); g_return_if_fail (post_marshal_notify != NULL); g_return_if_fail (closure->is_invalid == FALSE); g_return_if_fail (closure->in_marshal == FALSE); g_return_if_fail (closure->n_guards < CLOSURE_MAX_N_GUARDS); closure->notifiers = g_renew (GClosureNotifyData, closure->notifiers, CLOSURE_N_NOTIFIERS (closure) + 2); if (closure->n_inotifiers) closure->notifiers[(CLOSURE_N_MFUNCS (closure) + closure->n_fnotifiers + closure->n_inotifiers + 1)] = closure->notifiers[(CLOSURE_N_MFUNCS (closure) + closure->n_fnotifiers + 0)]; if (closure->n_inotifiers > 1) closure->notifiers[(CLOSURE_N_MFUNCS (closure) + closure->n_fnotifiers + closure->n_inotifiers)] = closure->notifiers[(CLOSURE_N_MFUNCS (closure) + closure->n_fnotifiers + 1)]; if (closure->n_fnotifiers) closure->notifiers[(CLOSURE_N_MFUNCS (closure) + closure->n_fnotifiers + 1)] = closure->notifiers[CLOSURE_N_MFUNCS (closure) + 0]; if (closure->n_fnotifiers > 1) closure->notifiers[(CLOSURE_N_MFUNCS (closure) + closure->n_fnotifiers)] = closure->notifiers[CLOSURE_N_MFUNCS (closure) + 1]; if (closure->n_guards) closure->notifiers[(closure->meta_marshal + closure->n_guards + closure->n_guards + 1)] = closure->notifiers[closure->meta_marshal + closure->n_guards]; i = closure->n_guards; closure->notifiers[closure->meta_marshal + i].data = pre_marshal_data; closure->notifiers[closure->meta_marshal + i].notify = pre_marshal_notify; closure->notifiers[closure->meta_marshal + i + 1].data = post_marshal_data; closure->notifiers[closure->meta_marshal + i + 1].notify = post_marshal_notify; INC (closure, n_guards); } /** * g_closure_add_finalize_notifier: (skip) * @closure: a #GClosure * @notify_data: data to pass to @notify_func * @notify_func: the callback function to register * * Registers a finalization notifier which will be called when the * reference count of @closure goes down to 0. Multiple finalization * notifiers on a single closure are invoked in unspecified order. If * a single call to g_closure_unref() results in the closure being * both invalidated and finalized, then the invalidate notifiers will * be run before the finalize notifiers. */ void g_closure_add_finalize_notifier (GClosure *closure, gpointer notify_data, GClosureNotify notify_func) { guint i; g_return_if_fail (closure != NULL); g_return_if_fail (notify_func != NULL); g_return_if_fail (closure->n_fnotifiers < CLOSURE_MAX_N_FNOTIFIERS); closure->notifiers = g_renew (GClosureNotifyData, closure->notifiers, CLOSURE_N_NOTIFIERS (closure) + 1); if (closure->n_inotifiers) closure->notifiers[(CLOSURE_N_MFUNCS (closure) + closure->n_fnotifiers + closure->n_inotifiers)] = closure->notifiers[(CLOSURE_N_MFUNCS (closure) + closure->n_fnotifiers + 0)]; i = CLOSURE_N_MFUNCS (closure) + closure->n_fnotifiers; closure->notifiers[i].data = notify_data; closure->notifiers[i].notify = notify_func; INC (closure, n_fnotifiers); } /** * g_closure_add_invalidate_notifier: (skip) * @closure: a #GClosure * @notify_data: data to pass to @notify_func * @notify_func: the callback function to register * * Registers an invalidation notifier which will be called when the * @closure is invalidated with g_closure_invalidate(). Invalidation * notifiers are invoked before finalization notifiers, in an * unspecified order. */ void g_closure_add_invalidate_notifier (GClosure *closure, gpointer notify_data, GClosureNotify notify_func) { guint i; g_return_if_fail (closure != NULL); g_return_if_fail (notify_func != NULL); g_return_if_fail (closure->is_invalid == FALSE); g_return_if_fail (closure->n_inotifiers < CLOSURE_MAX_N_INOTIFIERS); closure->notifiers = g_renew (GClosureNotifyData, closure->notifiers, CLOSURE_N_NOTIFIERS (closure) + 1); i = CLOSURE_N_MFUNCS (closure) + closure->n_fnotifiers + closure->n_inotifiers; closure->notifiers[i].data = notify_data; closure->notifiers[i].notify = notify_func; INC (closure, n_inotifiers); } static inline gboolean closure_try_remove_inotify (GClosure *closure, gpointer notify_data, GClosureNotify notify_func) { GClosureNotifyData *ndata, *nlast; nlast = closure->notifiers + CLOSURE_N_NOTIFIERS (closure) - 1; for (ndata = nlast + 1 - closure->n_inotifiers; ndata <= nlast; ndata++) if (ndata->notify == notify_func && ndata->data == notify_data) { DEC (closure, n_inotifiers); if (ndata < nlast) *ndata = *nlast; return TRUE; } return FALSE; } static inline gboolean closure_try_remove_fnotify (GClosure *closure, gpointer notify_data, GClosureNotify notify_func) { GClosureNotifyData *ndata, *nlast; nlast = closure->notifiers + CLOSURE_N_NOTIFIERS (closure) - closure->n_inotifiers - 1; for (ndata = nlast + 1 - closure->n_fnotifiers; ndata <= nlast; ndata++) if (ndata->notify == notify_func && ndata->data == notify_data) { DEC (closure, n_fnotifiers); if (ndata < nlast) *ndata = *nlast; if (closure->n_inotifiers) closure->notifiers[(CLOSURE_N_MFUNCS (closure) + closure->n_fnotifiers)] = closure->notifiers[(CLOSURE_N_MFUNCS (closure) + closure->n_fnotifiers + closure->n_inotifiers)]; return TRUE; } return FALSE; } /** * g_closure_ref: * @closure: #GClosure to increment the reference count on * * Increments the reference count on a closure to force it staying * alive while the caller holds a pointer to it. * * Returns: (transfer none): The @closure passed in, for convenience */ GClosure* g_closure_ref (GClosure *closure) { guint new_ref_count; g_return_val_if_fail (closure != NULL, NULL); g_return_val_if_fail (closure->ref_count > 0, NULL); g_return_val_if_fail (closure->ref_count < CLOSURE_MAX_REF_COUNT, NULL); INC_ASSIGN (closure, ref_count, &new_ref_count); g_return_val_if_fail (new_ref_count > 1, NULL); return closure; } /** * g_closure_invalidate: * @closure: GClosure to invalidate * * Sets a flag on the closure to indicate that its calling * environment has become invalid, and thus causes any future * invocations of g_closure_invoke() on this @closure to be * ignored. Also, invalidation notifiers installed on the closure will * be called at this point. Note that unless you are holding a * reference to the closure yourself, the invalidation notifiers may * unref the closure and cause it to be destroyed, so if you need to * access the closure after calling g_closure_invalidate(), make sure * that you've previously called g_closure_ref(). * * Note that g_closure_invalidate() will also be called when the * reference count of a closure drops to zero (unless it has already * been invalidated before). */ void g_closure_invalidate (GClosure *closure) { g_return_if_fail (closure != NULL); if (!closure->is_invalid) { gboolean was_invalid; g_closure_ref (closure); /* preserve floating flag */ SWAP (closure, is_invalid, TRUE, &was_invalid); /* invalidate only once */ if (!was_invalid) closure_invoke_notifiers (closure, INOTIFY); g_closure_unref (closure); } } /** * g_closure_unref: * @closure: #GClosure to decrement the reference count on * * Decrements the reference count of a closure after it was previously * incremented by the same caller. If no other callers are using the * closure, then the closure will be destroyed and freed. */ void g_closure_unref (GClosure *closure) { guint new_ref_count; g_return_if_fail (closure != NULL); g_return_if_fail (closure->ref_count > 0); if (closure->ref_count == 1) /* last unref, invalidate first */ g_closure_invalidate (closure); DEC_ASSIGN (closure, ref_count, &new_ref_count); if (new_ref_count == 0) { closure_invoke_notifiers (closure, FNOTIFY); g_free (closure->notifiers); g_free (closure); } } /** * g_closure_sink: * @closure: #GClosure to decrement the initial reference count on, if it's * still being held * * Takes over the initial ownership of a closure. Each closure is * initially created in a floating state, which * means that the initial reference count is not owned by any caller. * g_closure_sink() checks to see if the object is still floating, and * if so, unsets the floating state and decreases the reference * count. If the closure is not floating, g_closure_sink() does * nothing. The reason for the existance of the floating state is to * prevent cumbersome code sequences like: * |[ * closure = g_cclosure_new (cb_func, cb_data); * g_source_set_closure (source, closure); * g_closure_unref (closure); // XXX GObject doesn't really need this * ]| * Because g_source_set_closure() (and similar functions) take ownership of the * initial reference count, if it is unowned, we instead can write: * |[ * g_source_set_closure (source, g_cclosure_new (cb_func, cb_data)); * ]| * * Generally, this function is used together with g_closure_ref(). Ane example * of storing a closure for later notification looks like: * |[ * static GClosure *notify_closure = NULL; * void * foo_notify_set_closure (GClosure *closure) * { * if (notify_closure) * g_closure_unref (notify_closure); * notify_closure = closure; * if (notify_closure) * { * g_closure_ref (notify_closure); * g_closure_sink (notify_closure); * } * } * ]| * * Because g_closure_sink() may decrement the reference count of a closure * (if it hasn't been called on @closure yet) just like g_closure_unref(), * g_closure_ref() should be called prior to this function. */ void g_closure_sink (GClosure *closure) { g_return_if_fail (closure != NULL); g_return_if_fail (closure->ref_count > 0); /* floating is basically a kludge to avoid creating closures * with a ref_count of 0. so the intial ref_count a closure has * is unowned. with invoking g_closure_sink() code may * indicate that it takes over that intiial ref_count. */ if (closure->floating) { gboolean was_floating; SWAP (closure, floating, FALSE, &was_floating); /* unref floating flag only once */ if (was_floating) g_closure_unref (closure); } } /** * g_closure_remove_invalidate_notifier: (skip) * @closure: a #GClosure * @notify_data: data which was passed to g_closure_add_invalidate_notifier() * when registering @notify_func * @notify_func: the callback function to remove * * Removes an invalidation notifier. * * Notice that notifiers are automatically removed after they are run. */ void g_closure_remove_invalidate_notifier (GClosure *closure, gpointer notify_data, GClosureNotify notify_func) { g_return_if_fail (closure != NULL); g_return_if_fail (notify_func != NULL); if (closure->is_invalid && closure->in_inotify && /* account removal of notify_func() while it's called */ ((gpointer) closure->marshal) == ((gpointer) notify_func) && closure->data == notify_data) closure->marshal = NULL; else if (!closure_try_remove_inotify (closure, notify_data, notify_func)) g_warning (G_STRLOC ": unable to remove uninstalled invalidation notifier: %p (%p)", notify_func, notify_data); } /** * g_closure_remove_finalize_notifier: (skip) * @closure: a #GClosure * @notify_data: data which was passed to g_closure_add_finalize_notifier() * when registering @notify_func * @notify_func: the callback function to remove * * Removes a finalization notifier. * * Notice that notifiers are automatically removed after they are run. */ void g_closure_remove_finalize_notifier (GClosure *closure, gpointer notify_data, GClosureNotify notify_func) { g_return_if_fail (closure != NULL); g_return_if_fail (notify_func != NULL); if (closure->is_invalid && !closure->in_inotify && /* account removal of notify_func() while it's called */ ((gpointer) closure->marshal) == ((gpointer) notify_func) && closure->data == notify_data) closure->marshal = NULL; else if (!closure_try_remove_fnotify (closure, notify_data, notify_func)) g_warning (G_STRLOC ": unable to remove uninstalled finalization notifier: %p (%p)", notify_func, notify_data); } /** * g_closure_invoke: * @closure: a #GClosure * @return_value: (allow-none): 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: (allow-none): a context-dependent invocation hint * * Invokes the closure, i.e. executes the callback represented by the @closure. */ void g_closure_invoke (GClosure *closure, GValue /*out*/ *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint) { g_return_if_fail (closure != NULL); g_closure_ref (closure); /* preserve floating flag */ if (!closure->is_invalid) { GClosureMarshal marshal; gpointer marshal_data; gboolean in_marshal = closure->in_marshal; g_return_if_fail (closure->marshal || closure->meta_marshal); SET (closure, in_marshal, TRUE); if (closure->meta_marshal) { marshal_data = closure->notifiers[0].data; marshal = (GClosureMarshal) closure->notifiers[0].notify; } else { marshal_data = NULL; marshal = closure->marshal; } if (!in_marshal) closure_invoke_notifiers (closure, PRE_NOTIFY); marshal (closure, return_value, n_param_values, param_values, invocation_hint, marshal_data); if (!in_marshal) closure_invoke_notifiers (closure, POST_NOTIFY); SET (closure, in_marshal, in_marshal); } g_closure_unref (closure); } /** * g_closure_set_marshal: (skip) * @closure: a #GClosure * @marshal: a #GClosureMarshal function * * Sets the marshaller of @closure. The marshal_data * of @marshal provides a way for a meta marshaller to provide additional * information to the marshaller. (See g_closure_set_meta_marshal().) For * GObject's C predefined marshallers (the g_cclosure_marshal_*() * functions), what it provides is a callback function to use instead of * @closure->callback. */ void g_closure_set_marshal (GClosure *closure, GClosureMarshal marshal) { g_return_if_fail (closure != NULL); g_return_if_fail (marshal != NULL); if (closure->marshal && closure->marshal != marshal) g_warning ("attempt to override closure->marshal (%p) with new marshal (%p)", closure->marshal, marshal); else closure->marshal = marshal; } /** * g_cclosure_new: (skip) * @callback_func: the function to invoke * @user_data: user data to pass to @callback_func * @destroy_data: destroy notify to be called when @user_data is no longer used * * Creates a new closure which invokes @callback_func with @user_data as * the last parameter. * * Returns: a new #GCClosure */ GClosure* g_cclosure_new (GCallback callback_func, gpointer user_data, GClosureNotify destroy_data) { GClosure *closure; g_return_val_if_fail (callback_func != NULL, NULL); closure = g_closure_new_simple (sizeof (GCClosure), user_data); if (destroy_data) g_closure_add_finalize_notifier (closure, user_data, destroy_data); ((GCClosure*) closure)->callback = (gpointer) callback_func; return closure; } /** * g_cclosure_new_swap: (skip) * @callback_func: the function to invoke * @user_data: user data to pass to @callback_func * @destroy_data: destroy notify to be called when @user_data is no longer used * * Creates a new closure which invokes @callback_func with @user_data as * the first parameter. * * Returns: (transfer full): a new #GCClosure */ GClosure* g_cclosure_new_swap (GCallback callback_func, gpointer user_data, GClosureNotify destroy_data) { GClosure *closure; g_return_val_if_fail (callback_func != NULL, NULL); closure = g_closure_new_simple (sizeof (GCClosure), user_data); if (destroy_data) g_closure_add_finalize_notifier (closure, user_data, destroy_data); ((GCClosure*) closure)->callback = (gpointer) callback_func; SET (closure, derivative_flag, TRUE); return closure; } static void g_type_class_meta_marshal (GClosure *closure, GValue /*out*/ *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data) { GTypeClass *class; gpointer callback; /* GType itype = (GType) closure->data; */ guint offset = GPOINTER_TO_UINT (marshal_data); class = G_TYPE_INSTANCE_GET_CLASS (g_value_peek_pointer (param_values + 0), itype, GTypeClass); callback = G_STRUCT_MEMBER (gpointer, class, offset); if (callback) closure->marshal (closure, return_value, n_param_values, param_values, invocation_hint, callback); } static void g_type_iface_meta_marshal (GClosure *closure, GValue /*out*/ *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data) { GTypeClass *class; gpointer callback; GType itype = (GType) closure->data; guint offset = GPOINTER_TO_UINT (marshal_data); class = G_TYPE_INSTANCE_GET_INTERFACE (g_value_peek_pointer (param_values + 0), itype, GTypeClass); callback = G_STRUCT_MEMBER (gpointer, class, offset); if (callback) closure->marshal (closure, return_value, n_param_values, param_values, invocation_hint, callback); } /** * g_signal_type_cclosure_new: * @itype: the #GType identifier of an interface or classed type * @struct_offset: the offset of the member function of @itype's class * structure which is to be invoked by the new closure * * Creates a new closure which invokes the function found at the offset * @struct_offset in the class structure of the interface or classed type * identified by @itype. * * Returns: a new #GCClosure */ GClosure* g_signal_type_cclosure_new (GType itype, guint struct_offset) { GClosure *closure; g_return_val_if_fail (G_TYPE_IS_CLASSED (itype) || G_TYPE_IS_INTERFACE (itype), NULL); g_return_val_if_fail (struct_offset >= sizeof (GTypeClass), NULL); closure = g_closure_new_simple (sizeof (GClosure), (gpointer) itype); if (G_TYPE_IS_INTERFACE (itype)) g_closure_set_meta_marshal (closure, GUINT_TO_POINTER (struct_offset), g_type_iface_meta_marshal); else g_closure_set_meta_marshal (closure, GUINT_TO_POINTER (struct_offset), g_type_class_meta_marshal); return closure; } #include static ffi_type * value_to_ffi_type (const GValue *gvalue, gpointer *value) { ffi_type *rettype = NULL; GType type = g_type_fundamental (G_VALUE_TYPE (gvalue)); g_assert (type != G_TYPE_INVALID); switch (type) { case G_TYPE_BOOLEAN: case G_TYPE_CHAR: case G_TYPE_INT: case G_TYPE_ENUM: rettype = &ffi_type_sint; *value = (gpointer)&(gvalue->data[0].v_int); break; case G_TYPE_UCHAR: case G_TYPE_UINT: case G_TYPE_FLAGS: rettype = &ffi_type_uint; *value = (gpointer)&(gvalue->data[0].v_uint); break; case G_TYPE_STRING: case G_TYPE_OBJECT: case G_TYPE_BOXED: case G_TYPE_PARAM: case G_TYPE_POINTER: case G_TYPE_INTERFACE: case G_TYPE_VARIANT: rettype = &ffi_type_pointer; *value = (gpointer)&(gvalue->data[0].v_pointer); break; case G_TYPE_FLOAT: rettype = &ffi_type_float; *value = (gpointer)&(gvalue->data[0].v_float); break; case G_TYPE_DOUBLE: rettype = &ffi_type_double; *value = (gpointer)&(gvalue->data[0].v_double); break; case G_TYPE_LONG: rettype = &ffi_type_slong; *value = (gpointer)&(gvalue->data[0].v_long); break; case G_TYPE_ULONG: rettype = &ffi_type_ulong; *value = (gpointer)&(gvalue->data[0].v_ulong); break; case G_TYPE_INT64: rettype = &ffi_type_sint64; *value = (gpointer)&(gvalue->data[0].v_int64); break; case G_TYPE_UINT64: rettype = &ffi_type_uint64; *value = (gpointer)&(gvalue->data[0].v_uint64); break; default: rettype = &ffi_type_pointer; *value = NULL; g_warning ("value_to_ffi_type: Unsupported fundamental type: %s", g_type_name (type)); break; } return rettype; } static void value_from_ffi_type (GValue *gvalue, gpointer *value) { switch (g_type_fundamental (G_VALUE_TYPE (gvalue))) { case G_TYPE_INT: g_value_set_int (gvalue, *(gint*)value); break; case G_TYPE_FLOAT: g_value_set_float (gvalue, *(gfloat*)value); break; case G_TYPE_DOUBLE: g_value_set_double (gvalue, *(gdouble*)value); break; case G_TYPE_BOOLEAN: g_value_set_boolean (gvalue, *(gboolean*)value); break; case G_TYPE_STRING: g_value_set_string (gvalue, *(gchar**)value); break; case G_TYPE_CHAR: g_value_set_char (gvalue, *(gchar*)value); break; case G_TYPE_UCHAR: g_value_set_uchar (gvalue, *(guchar*)value); break; case G_TYPE_UINT: g_value_set_uint (gvalue, *(guint*)value); break; case G_TYPE_POINTER: g_value_set_pointer (gvalue, *(gpointer*)value); break; case G_TYPE_LONG: g_value_set_long (gvalue, *(glong*)value); break; case G_TYPE_ULONG: g_value_set_ulong (gvalue, *(gulong*)value); break; case G_TYPE_INT64: g_value_set_int64 (gvalue, *(gint64*)value); break; case G_TYPE_UINT64: g_value_set_uint64 (gvalue, *(guint64*)value); break; case G_TYPE_BOXED: g_value_set_boxed (gvalue, *(gpointer*)value); break; case G_TYPE_ENUM: g_value_set_enum (gvalue, *(gint*)value); break; case G_TYPE_FLAGS: g_value_set_flags (gvalue, *(guint*)value); break; case G_TYPE_PARAM: g_value_set_param (gvalue, *(gpointer*)value); break; case G_TYPE_OBJECT: g_value_set_object (gvalue, *(gpointer*)value); break; default: g_warning ("value_from_ffi_type: Unsupported fundamental type: %s", g_type_name (g_type_fundamental (G_VALUE_TYPE (gvalue)))); } } /** * g_cclosure_marshal_generic: * @closure: A #GClosure. * @return_gvalue: 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: An array of #GValues holding the arguments * on which to invoke the callback of closure. * @invocation_hint: The invocation hint given as the last argument to * g_closure_invoke(). * @marshal_data: Additional data specified when registering the * marshaller, see g_closure_set_marshal() and * g_closure_set_meta_marshal() * * A generic marshaller function implemented via libffi. * * Since: 2.30 */ void g_cclosure_marshal_generic (GClosure *closure, GValue *return_gvalue, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data) { ffi_type *rtype; void *rvalue; int n_args; ffi_type **atypes; void **args; int i; ffi_cif cif; GCClosure *cc = (GCClosure*) closure; if (return_gvalue && G_VALUE_TYPE (return_gvalue)) { rtype = value_to_ffi_type (return_gvalue, &rvalue); } else { rtype = &ffi_type_void; } rvalue = g_alloca (MAX (rtype->size, sizeof (ffi_arg))); n_args = n_param_values + 1; atypes = g_alloca (sizeof (ffi_type *) * n_args); args = g_alloca (sizeof (gpointer) * n_args); if (G_CCLOSURE_SWAP_DATA (closure)) { atypes[n_args-1] = value_to_ffi_type (param_values + 0, &args[n_args-1]); atypes[0] = &ffi_type_pointer; args[0] = &closure->data; } else { atypes[0] = value_to_ffi_type (param_values + 0, &args[0]); atypes[n_args-1] = &ffi_type_pointer; args[n_args-1] = &closure->data; } for (i = 1; i < n_args - 1; i++) atypes[i] = value_to_ffi_type (param_values + i, &args[i]); if (ffi_prep_cif (&cif, FFI_DEFAULT_ABI, n_args, rtype, atypes) != FFI_OK) return; ffi_call (&cif, marshal_data ? marshal_data : cc->callback, rvalue, args); if (return_gvalue && G_VALUE_TYPE (return_gvalue)) value_from_ffi_type (return_gvalue, rvalue); } /** * g_cclosure_marshal_VOID__VOID: * @closure: the #GClosure to which the marshaller belongs * @return_value: ignored * @n_param_values: 1 * @param_values: a #GValue array holding only the instance * @invocation_hint: the invocation hint given as the last argument * to g_closure_invoke() * @marshal_data: additional data specified when registering the marshaller * * A marshaller for a #GCClosure with a callback of type * void (*callback) (gpointer instance, gpointer user_data). */ /** * g_cclosure_marshal_VOID__BOOLEAN: * @closure: the #GClosure to which the marshaller belongs * @return_value: ignored * @n_param_values: 2 * @param_values: a #GValue array holding the instance and the #gboolean parameter * @invocation_hint: the invocation hint given as the last argument * to g_closure_invoke() * @marshal_data: additional data specified when registering the marshaller * * A marshaller for a #GCClosure with a callback of type * void (*callback) (gpointer instance, gboolean arg1, gpointer user_data). */ /** * g_cclosure_marshal_VOID__CHAR: * @closure: the #GClosure to which the marshaller belongs * @return_value: ignored * @n_param_values: 2 * @param_values: a #GValue array holding the instance and the #gchar parameter * @invocation_hint: the invocation hint given as the last argument * to g_closure_invoke() * @marshal_data: additional data specified when registering the marshaller * * A marshaller for a #GCClosure with a callback of type * void (*callback) (gpointer instance, gchar arg1, gpointer user_data). */ /** * g_cclosure_marshal_VOID__UCHAR: * @closure: the #GClosure to which the marshaller belongs * @return_value: ignored * @n_param_values: 2 * @param_values: a #GValue array holding the instance and the #guchar parameter * @invocation_hint: the invocation hint given as the last argument * to g_closure_invoke() * @marshal_data: additional data specified when registering the marshaller * * A marshaller for a #GCClosure with a callback of type * void (*callback) (gpointer instance, guchar arg1, gpointer user_data). */ /** * g_cclosure_marshal_VOID__INT: * @closure: the #GClosure to which the marshaller belongs * @return_value: ignored * @n_param_values: 2 * @param_values: a #GValue array holding the instance and the #gint parameter * @invocation_hint: the invocation hint given as the last argument * to g_closure_invoke() * @marshal_data: additional data specified when registering the marshaller * * A marshaller for a #GCClosure with a callback of type * void (*callback) (gpointer instance, gint arg1, gpointer user_data). */ /** * g_cclosure_marshal_VOID__UINT: * @closure: the #GClosure to which the marshaller belongs * @return_value: ignored * @n_param_values: 2 * @param_values: a #GValue array holding the instance and the #guint parameter * @invocation_hint: the invocation hint given as the last argument * to g_closure_invoke() * @marshal_data: additional data specified when registering the marshaller * * A marshaller for a #GCClosure with a callback of type * void (*callback) (gpointer instance, guint arg1, gpointer user_data). */ /** * g_cclosure_marshal_VOID__LONG: * @closure: the #GClosure to which the marshaller belongs * @return_value: ignored * @n_param_values: 2 * @param_values: a #GValue array holding the instance and the #glong parameter * @invocation_hint: the invocation hint given as the last argument * to g_closure_invoke() * @marshal_data: additional data specified when registering the marshaller * * A marshaller for a #GCClosure with a callback of type * void (*callback) (gpointer instance, glong arg1, gpointer user_data). */ /** * g_cclosure_marshal_VOID__ULONG: * @closure: the #GClosure to which the marshaller belongs * @return_value: ignored * @n_param_values: 2 * @param_values: a #GValue array holding the instance and the #gulong parameter * @invocation_hint: the invocation hint given as the last argument * to g_closure_invoke() * @marshal_data: additional data specified when registering the marshaller * * A marshaller for a #GCClosure with a callback of type * void (*callback) (gpointer instance, gulong arg1, gpointer user_data). */ /** * g_cclosure_marshal_VOID__ENUM: * @closure: the #GClosure to which the marshaller belongs * @return_value: ignored * @n_param_values: 2 * @param_values: a #GValue array holding the instance and the enumeration parameter * @invocation_hint: the invocation hint given as the last argument * to g_closure_invoke() * @marshal_data: additional data specified when registering the marshaller * * A marshaller for a #GCClosure with a callback of type * void (*callback) (gpointer instance, gint arg1, gpointer user_data) where the #gint parameter denotes an enumeration type.. */ /** * g_cclosure_marshal_VOID__FLAGS: * @closure: the #GClosure to which the marshaller belongs * @return_value: ignored * @n_param_values: 2 * @param_values: a #GValue array holding the instance and the flags parameter * @invocation_hint: the invocation hint given as the last argument * to g_closure_invoke() * @marshal_data: additional data specified when registering the marshaller * * A marshaller for a #GCClosure with a callback of type * void (*callback) (gpointer instance, gint arg1, gpointer user_data) where the #gint parameter denotes a flags type. */ /** * g_cclosure_marshal_VOID__FLOAT: * @closure: the #GClosure to which the marshaller belongs * @return_value: ignored * @n_param_values: 2 * @param_values: a #GValue array holding the instance and the #gfloat parameter * @invocation_hint: the invocation hint given as the last argument * to g_closure_invoke() * @marshal_data: additional data specified when registering the marshaller * * A marshaller for a #GCClosure with a callback of type * void (*callback) (gpointer instance, gfloat arg1, gpointer user_data). */ /** * g_cclosure_marshal_VOID__DOUBLE: * @closure: the #GClosure to which the marshaller belongs * @return_value: ignored * @n_param_values: 2 * @param_values: a #GValue array holding the instance and the #gdouble parameter * @invocation_hint: the invocation hint given as the last argument * to g_closure_invoke() * @marshal_data: additional data specified when registering the marshaller * * A marshaller for a #GCClosure with a callback of type * void (*callback) (gpointer instance, gdouble arg1, gpointer user_data). */ /** * g_cclosure_marshal_VOID__STRING: * @closure: the #GClosure to which the marshaller belongs * @return_value: ignored * @n_param_values: 2 * @param_values: a #GValue array holding the instance and the #gchar* parameter * @invocation_hint: the invocation hint given as the last argument * to g_closure_invoke() * @marshal_data: additional data specified when registering the marshaller * * A marshaller for a #GCClosure with a callback of type * void (*callback) (gpointer instance, const gchar *arg1, gpointer user_data). */ /** * g_cclosure_marshal_VOID__PARAM: * @closure: the #GClosure to which the marshaller belongs * @return_value: ignored * @n_param_values: 2 * @param_values: a #GValue array holding the instance and the #GParamSpec* parameter * @invocation_hint: the invocation hint given as the last argument * to g_closure_invoke() * @marshal_data: additional data specified when registering the marshaller * * A marshaller for a #GCClosure with a callback of type * void (*callback) (gpointer instance, GParamSpec *arg1, gpointer user_data). */ /** * g_cclosure_marshal_VOID__BOXED: * @closure: the #GClosure to which the marshaller belongs * @return_value: ignored * @n_param_values: 2 * @param_values: a #GValue array holding the instance and the #GBoxed* parameter * @invocation_hint: the invocation hint given as the last argument * to g_closure_invoke() * @marshal_data: additional data specified when registering the marshaller * * A marshaller for a #GCClosure with a callback of type * void (*callback) (gpointer instance, GBoxed *arg1, gpointer user_data). */ /** * g_cclosure_marshal_VOID__POINTER: * @closure: the #GClosure to which the marshaller belongs * @return_value: ignored * @n_param_values: 2 * @param_values: a #GValue array holding the instance and the #gpointer parameter * @invocation_hint: the invocation hint given as the last argument * to g_closure_invoke() * @marshal_data: additional data specified when registering the marshaller * * A marshaller for a #GCClosure with a callback of type * void (*callback) (gpointer instance, gpointer arg1, gpointer user_data). */ /** * g_cclosure_marshal_VOID__OBJECT: * @closure: the #GClosure to which the marshaller belongs * @return_value: ignored * @n_param_values: 2 * @param_values: a #GValue array holding the instance and the #GObject* parameter * @invocation_hint: the invocation hint given as the last argument * to g_closure_invoke() * @marshal_data: additional data specified when registering the marshaller * * A marshaller for a #GCClosure with a callback of type * void (*callback) (gpointer instance, GObject *arg1, gpointer user_data). */ /** * g_cclosure_marshal_VOID__VARIANT: * @closure: the #GClosure to which the marshaller belongs * @return_value: ignored * @n_param_values: 2 * @param_values: a #GValue array holding the instance and the #GVariant* parameter * @invocation_hint: the invocation hint given as the last argument * to g_closure_invoke() * @marshal_data: additional data specified when registering the marshaller * * A marshaller for a #GCClosure with a callback of type * void (*callback) (gpointer instance, GVariant *arg1, gpointer user_data). * * Since: 2.26 */ /** * g_cclosure_marshal_VOID__UINT_POINTER: * @closure: the #GClosure to which the marshaller belongs * @return_value: ignored * @n_param_values: 3 * @param_values: a #GValue array holding instance, arg1 and arg2 * @invocation_hint: the invocation hint given as the last argument * to g_closure_invoke() * @marshal_data: additional data specified when registering the marshaller * * A marshaller for a #GCClosure with a callback of type * void (*callback) (gpointer instance, guint arg1, gpointer arg2, gpointer user_data). */ /** * g_cclosure_marshal_BOOLEAN__FLAGS: * @closure: the #GClosure to which the marshaller belongs * @return_value: a #GValue which can store the returned #gboolean * @n_param_values: 2 * @param_values: a #GValue array holding instance and arg1 * @invocation_hint: the invocation hint given as the last argument * to g_closure_invoke() * @marshal_data: additional data specified when registering the marshaller * * A marshaller for a #GCClosure with a callback of type * gboolean (*callback) (gpointer instance, gint arg1, gpointer user_data) where the #gint parameter * denotes a flags type. */ /** * g_cclosure_marshal_BOOL__FLAGS: * * Another name for g_cclosure_marshal_BOOLEAN__FLAGS(). */ /** * g_cclosure_marshal_STRING__OBJECT_POINTER: * @closure: the #GClosure to which the marshaller belongs * @return_value: a #GValue, which can store the returned string * @n_param_values: 3 * @param_values: a #GValue array holding instance, arg1 and arg2 * @invocation_hint: the invocation hint given as the last argument * to g_closure_invoke() * @marshal_data: additional data specified when registering the marshaller * * A marshaller for a #GCClosure with a callback of type * gchar* (*callback) (gpointer instance, GObject *arg1, gpointer arg2, gpointer user_data). */ /** * g_cclosure_marshal_BOOLEAN__OBJECT_BOXED_BOXED: * @closure: the #GClosure to which the marshaller belongs * @return_value: a #GValue, which can store the returned string * @n_param_values: 3 * @param_values: a #GValue array holding instance, arg1 and arg2 * @invocation_hint: the invocation hint given as the last argument * to g_closure_invoke() * @marshal_data: additional data specified when registering the marshaller * * A marshaller for a #GCClosure with a callback of type * gboolean (*callback) (gpointer instance, GBoxed *arg1, GBoxed *arg2, gpointer user_data). * * Since: 2.26 */