/* GObject - GLib Type, Object, Parameter and Signal Library
* Copyright (C) 2000-2001 Red Hat, Inc.
*
* SPDX-License-Identifier: LGPL-2.1-or-later
*
* 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 .
*
* this code is based on the original GtkSignal implementation
* for the Gtk+ library by Peter Mattis
*/
/*
* MT safe
*/
#include "config.h"
#include
#include
#include "gsignal.h"
#include "gtype-private.h"
#include "gbsearcharray.h"
#include "gvaluecollector.h"
#include "gvaluetypes.h"
#include "gobject.h"
#include "genums.h"
#include "gobject_trace.h"
/**
* SECTION:signals
* @short_description: A means for customization of object behaviour
* and a general purpose notification mechanism
* @title: Signals
*
* The basic concept of the signal system is that of the emission
* of a signal. Signals are introduced per-type and are identified
* through strings. Signals introduced for a parent type are available
* in derived types as well, so basically they are a per-type facility
* that is inherited.
*
* A signal emission mainly involves invocation of a certain set of
* callbacks in precisely defined manner. There are two main categories
* of such callbacks, per-object ones and user provided ones.
* (Although signals can deal with any kind of instantiatable type, I'm
* referring to those types as "object types" in the following, simply
* because that is the context most users will encounter signals in.)
* The per-object callbacks are most often referred to as "object method
* handler" or "default (signal) handler", while user provided callbacks are
* usually just called "signal handler".
*
* The object method handler is provided at signal creation time (this most
* frequently happens at the end of an object class' creation), while user
* provided handlers are frequently connected and disconnected to/from a
* certain signal on certain object instances.
*
* A signal emission consists of five stages, unless prematurely stopped:
*
* 1. Invocation of the object method handler for %G_SIGNAL_RUN_FIRST signals
*
* 2. Invocation of normal user-provided signal handlers (where the @after
* flag is not set)
*
* 3. Invocation of the object method handler for %G_SIGNAL_RUN_LAST signals
*
* 4. Invocation of user provided signal handlers (where the @after flag is set)
*
* 5. Invocation of the object method handler for %G_SIGNAL_RUN_CLEANUP signals
*
* The user-provided signal handlers are called in the order they were
* connected in.
*
* All handlers may prematurely stop a signal emission, and any number of
* handlers may be connected, disconnected, blocked or unblocked during
* a signal emission.
*
* There are certain criteria for skipping user handlers in stages 2 and 4
* of a signal emission.
*
* First, user handlers may be blocked. Blocked handlers are omitted during
* callback invocation, to return from the blocked state, a handler has to
* get unblocked exactly the same amount of times it has been blocked before.
*
* Second, upon emission of a %G_SIGNAL_DETAILED signal, an additional
* @detail argument passed in to g_signal_emit() has to match the detail
* argument of the signal handler currently subject to invocation.
* Specification of no detail argument for signal handlers (omission of the
* detail part of the signal specification upon connection) serves as a
* wildcard and matches any detail argument passed in to emission.
*
* While the @detail argument is typically used to pass an object property name
* (as with #GObject::notify), no specific format is mandated for the detail
* string, other than that it must be non-empty.
*
* ## Memory management of signal handlers # {#signal-memory-management}
*
* If you are connecting handlers to signals and using a #GObject instance as
* your signal handler user data, you should remember to pair calls to
* g_signal_connect() with calls to g_signal_handler_disconnect() or
* g_signal_handlers_disconnect_by_func(). While signal handlers are
* automatically disconnected when the object emitting the signal is finalised,
* they are not automatically disconnected when the signal handler user data is
* destroyed. If this user data is a #GObject instance, using it from a
* signal handler after it has been finalised is an error.
*
* There are two strategies for managing such user data. The first is to
* disconnect the signal handler (using g_signal_handler_disconnect() or
* g_signal_handlers_disconnect_by_func()) when the user data (object) is
* finalised; this has to be implemented manually. For non-threaded programs,
* g_signal_connect_object() can be used to implement this automatically.
* Currently, however, it is unsafe to use in threaded programs.
*
* The second is to hold a strong reference on the user data until after the
* signal is disconnected for other reasons. This can be implemented
* automatically using g_signal_connect_data().
*
* The first approach is recommended, as the second approach can result in
* effective memory leaks of the user data if the signal handler is never
* disconnected for some reason.
*/
#define REPORT_BUG "please report occurrence circumstances to https://gitlab.gnome.org/GNOME/glib/issues/new"
/* --- typedefs --- */
typedef struct _SignalNode SignalNode;
typedef struct _SignalKey SignalKey;
typedef struct _Emission Emission;
typedef struct _Handler Handler;
typedef struct _HandlerList HandlerList;
typedef struct _HandlerMatch HandlerMatch;
typedef enum
{
EMISSION_STOP,
EMISSION_RUN,
EMISSION_HOOK,
EMISSION_RESTART
} EmissionState;
/* --- prototypes --- */
static inline guint signal_id_lookup (const gchar *name,
GType itype);
static void signal_destroy_R (SignalNode *signal_node);
static inline HandlerList* handler_list_ensure (guint signal_id,
gpointer instance);
static inline HandlerList* handler_list_lookup (guint signal_id,
gpointer instance);
static inline Handler* handler_new (guint signal_id,
gpointer instance,
gboolean after);
static void handler_insert (guint signal_id,
gpointer instance,
Handler *handler);
static Handler* handler_lookup (gpointer instance,
gulong handler_id,
GClosure *closure,
guint *signal_id_p);
static inline HandlerMatch* handler_match_prepend (HandlerMatch *list,
Handler *handler,
guint signal_id);
static inline HandlerMatch* handler_match_free1_R (HandlerMatch *node,
gpointer instance);
static HandlerMatch* handlers_find (gpointer instance,
GSignalMatchType mask,
guint signal_id,
GQuark detail,
GClosure *closure,
gpointer func,
gpointer data,
gboolean one_and_only);
static inline void handler_ref (Handler *handler);
static inline void handler_unref_R (guint signal_id,
gpointer instance,
Handler *handler);
static gint handler_lists_cmp (gconstpointer node1,
gconstpointer node2);
static inline void emission_push (Emission *emission);
static inline void emission_pop (Emission *emission);
static inline Emission* emission_find (guint signal_id,
GQuark detail,
gpointer instance);
static gint class_closures_cmp (gconstpointer node1,
gconstpointer node2);
static gint signal_key_cmp (gconstpointer node1,
gconstpointer node2);
static gboolean signal_emit_unlocked_R (SignalNode *node,
GQuark detail,
gpointer instance,
GValue *return_value,
const GValue *instance_and_params);
static void add_invalid_closure_notify (Handler *handler,
gpointer instance);
static void remove_invalid_closure_notify (Handler *handler,
gpointer instance);
static void invalid_closure_notify (gpointer data,
GClosure *closure);
static const gchar * type_debug_name (GType type);
static void node_check_deprecated (const SignalNode *node);
static void node_update_single_va_closure (SignalNode *node);
/* --- structures --- */
typedef struct
{
GSignalAccumulator func;
gpointer data;
} SignalAccumulator;
typedef struct
{
GHook hook;
GQuark detail;
} SignalHook;
#define SIGNAL_HOOK(hook) ((SignalHook*) (hook))
struct _SignalNode
{
/* permanent portion */
guint signal_id;
GType itype;
const gchar *name;
guint destroyed : 1;
/* reinitializable portion */
guint flags : 9;
guint n_params : 8;
guint single_va_closure_is_valid : 1;
guint single_va_closure_is_after : 1;
GType *param_types; /* mangled with G_SIGNAL_TYPE_STATIC_SCOPE flag */
GType return_type; /* mangled with G_SIGNAL_TYPE_STATIC_SCOPE flag */
GBSearchArray *class_closure_bsa;
SignalAccumulator *accumulator;
GSignalCMarshaller c_marshaller;
GSignalCVaMarshaller va_marshaller;
GHookList *emission_hooks;
GClosure *single_va_closure;
};
#define SINGLE_VA_CLOSURE_EMPTY_MAGIC GINT_TO_POINTER(1) /* indicates single_va_closure is valid but empty */
struct _SignalKey
{
GType itype;
GQuark quark;
guint signal_id;
};
struct _Emission
{
Emission *next;
gpointer instance;
GSignalInvocationHint ihint;
EmissionState state;
GType chain_type;
};
struct _HandlerList
{
guint signal_id;
Handler *handlers;
Handler *tail_before; /* normal signal handlers are appended here */
Handler *tail_after; /* CONNECT_AFTER handlers are appended here */
};
struct _Handler
{
gulong sequential_number;
Handler *next;
Handler *prev;
GQuark detail;
guint signal_id;
guint ref_count;
guint block_count : 16;
#define HANDLER_MAX_BLOCK_COUNT (1 << 16)
guint after : 1;
guint has_invalid_closure_notify : 1;
GClosure *closure;
gpointer instance;
};
struct _HandlerMatch
{
Handler *handler;
HandlerMatch *next;
guint signal_id;
};
typedef struct
{
GType instance_type; /* 0 for default closure */
GClosure *closure;
} ClassClosure;
/* --- variables --- */
static GBSearchArray *g_signal_key_bsa = NULL;
static const GBSearchConfig g_signal_key_bconfig = {
sizeof (SignalKey),
signal_key_cmp,
G_BSEARCH_ARRAY_ALIGN_POWER2,
};
static GBSearchConfig g_signal_hlbsa_bconfig = {
sizeof (HandlerList),
handler_lists_cmp,
0,
};
static GBSearchConfig g_class_closure_bconfig = {
sizeof (ClassClosure),
class_closures_cmp,
0,
};
static GHashTable *g_handler_list_bsa_ht = NULL;
static Emission *g_emissions = NULL;
static gulong g_handler_sequential_number = 1;
static GHashTable *g_handlers = NULL;
G_LOCK_DEFINE_STATIC (g_signal_mutex);
#define SIGNAL_LOCK() G_LOCK (g_signal_mutex)
#define SIGNAL_UNLOCK() G_UNLOCK (g_signal_mutex)
/* --- signal nodes --- */
static guint g_n_signal_nodes = 0;
static SignalNode **g_signal_nodes = NULL;
static inline SignalNode*
LOOKUP_SIGNAL_NODE (guint signal_id)
{
if (signal_id < g_n_signal_nodes)
return g_signal_nodes[signal_id];
else
return NULL;
}
/* --- functions --- */
/* @key must have already been validated with is_valid()
* Modifies @key in place. */
static void
canonicalize_key (gchar *key)
{
gchar *p;
for (p = key; *p != 0; p++)
{
gchar c = *p;
if (c == '_')
*p = '-';
}
}
/* @key must have already been validated with is_valid() */
static gboolean
is_canonical (const gchar *key)
{
return (strchr (key, '_') == NULL);
}
/**
* g_signal_is_valid_name:
* @name: the canonical name of the signal
*
* Validate a signal name. This can be useful for dynamically-generated signals
* which need to be validated at run-time before actually trying to create them.
*
* See [canonical parameter names][canonical-parameter-names] for details of
* the rules for valid names. The rules for signal names are the same as those
* for property names.
*
* Returns: %TRUE if @name is a valid signal name, %FALSE otherwise.
* Since: 2.66
*/
gboolean
g_signal_is_valid_name (const gchar *name)
{
/* FIXME: We allow this, against our own documentation (the leading `-` is
* invalid), because GTK has historically used this. */
if (g_str_equal (name, "-gtk-private-changed"))
return TRUE;
return g_param_spec_is_valid_name (name);
}
static inline guint
signal_id_lookup (const gchar *name,
GType itype)
{
GQuark quark;
GType *ifaces, type = itype;
SignalKey key;
guint n_ifaces;
quark = g_quark_try_string (name);
key.quark = quark;
/* try looking up signals for this type and its ancestors */
do
{
SignalKey *signal_key;
key.itype = type;
signal_key = g_bsearch_array_lookup (g_signal_key_bsa, &g_signal_key_bconfig, &key);
if (signal_key)
return signal_key->signal_id;
type = g_type_parent (type);
}
while (type);
/* no luck, try interfaces it exports */
ifaces = g_type_interfaces (itype, &n_ifaces);
while (n_ifaces--)
{
SignalKey *signal_key;
key.itype = ifaces[n_ifaces];
signal_key = g_bsearch_array_lookup (g_signal_key_bsa, &g_signal_key_bconfig, &key);
if (signal_key)
{
g_free (ifaces);
return signal_key->signal_id;
}
}
g_free (ifaces);
/* If the @name is non-canonical, try again. This is the slow path — people
* should use canonical names in their queries if they want performance. */
if (!is_canonical (name))
{
guint signal_id;
gchar *name_copy = g_strdup (name);
canonicalize_key (name_copy);
signal_id = signal_id_lookup (name_copy, itype);
g_free (name_copy);
return signal_id;
}
return 0;
}
static gint
class_closures_cmp (gconstpointer node1,
gconstpointer node2)
{
const ClassClosure *c1 = node1, *c2 = node2;
return G_BSEARCH_ARRAY_CMP (c1->instance_type, c2->instance_type);
}
static gint
handler_lists_cmp (gconstpointer node1,
gconstpointer node2)
{
const HandlerList *hlist1 = node1, *hlist2 = node2;
return G_BSEARCH_ARRAY_CMP (hlist1->signal_id, hlist2->signal_id);
}
static inline HandlerList*
handler_list_ensure (guint signal_id,
gpointer instance)
{
GBSearchArray *hlbsa = g_hash_table_lookup (g_handler_list_bsa_ht, instance);
HandlerList key;
key.signal_id = signal_id;
key.handlers = NULL;
key.tail_before = NULL;
key.tail_after = NULL;
if (!hlbsa)
{
hlbsa = g_bsearch_array_create (&g_signal_hlbsa_bconfig);
hlbsa = g_bsearch_array_insert (hlbsa, &g_signal_hlbsa_bconfig, &key);
g_hash_table_insert (g_handler_list_bsa_ht, instance, hlbsa);
}
else
{
GBSearchArray *o = hlbsa;
hlbsa = g_bsearch_array_insert (o, &g_signal_hlbsa_bconfig, &key);
if (hlbsa != o)
g_hash_table_insert (g_handler_list_bsa_ht, instance, hlbsa);
}
return g_bsearch_array_lookup (hlbsa, &g_signal_hlbsa_bconfig, &key);
}
static inline HandlerList*
handler_list_lookup (guint signal_id,
gpointer instance)
{
GBSearchArray *hlbsa = g_hash_table_lookup (g_handler_list_bsa_ht, instance);
HandlerList key;
key.signal_id = signal_id;
return hlbsa ? g_bsearch_array_lookup (hlbsa, &g_signal_hlbsa_bconfig, &key) : NULL;
}
static guint
handler_hash (gconstpointer key)
{
return (guint)((Handler*)key)->sequential_number;
}
static gboolean
handler_equal (gconstpointer a, gconstpointer b)
{
Handler *ha = (Handler *)a;
Handler *hb = (Handler *)b;
return (ha->sequential_number == hb->sequential_number) &&
(ha->instance == hb->instance);
}
static Handler*
handler_lookup (gpointer instance,
gulong handler_id,
GClosure *closure,
guint *signal_id_p)
{
GBSearchArray *hlbsa;
if (handler_id)
{
Handler key;
key.sequential_number = handler_id;
key.instance = instance;
return g_hash_table_lookup (g_handlers, &key);
}
hlbsa = g_hash_table_lookup (g_handler_list_bsa_ht, instance);
if (hlbsa)
{
guint i;
for (i = 0; i < hlbsa->n_nodes; i++)
{
HandlerList *hlist = g_bsearch_array_get_nth (hlbsa, &g_signal_hlbsa_bconfig, i);
Handler *handler;
for (handler = hlist->handlers; handler; handler = handler->next)
if (closure ? (handler->closure == closure) : (handler->sequential_number == handler_id))
{
if (signal_id_p)
*signal_id_p = hlist->signal_id;
return handler;
}
}
}
return NULL;
}
static inline HandlerMatch*
handler_match_prepend (HandlerMatch *list,
Handler *handler,
guint signal_id)
{
HandlerMatch *node;
node = g_slice_new (HandlerMatch);
node->handler = handler;
node->next = list;
node->signal_id = signal_id;
handler_ref (handler);
return node;
}
static inline HandlerMatch*
handler_match_free1_R (HandlerMatch *node,
gpointer instance)
{
HandlerMatch *next = node->next;
handler_unref_R (node->signal_id, instance, node->handler);
g_slice_free (HandlerMatch, node);
return next;
}
static HandlerMatch*
handlers_find (gpointer instance,
GSignalMatchType mask,
guint signal_id,
GQuark detail,
GClosure *closure,
gpointer func,
gpointer data,
gboolean one_and_only)
{
HandlerMatch *mlist = NULL;
if (mask & G_SIGNAL_MATCH_ID)
{
HandlerList *hlist = handler_list_lookup (signal_id, instance);
Handler *handler;
SignalNode *node = NULL;
if (mask & G_SIGNAL_MATCH_FUNC)
{
node = LOOKUP_SIGNAL_NODE (signal_id);
if (!node || !node->c_marshaller)
return NULL;
}
mask = ~mask;
for (handler = hlist ? hlist->handlers : NULL; handler; handler = handler->next)
if (handler->sequential_number &&
((mask & G_SIGNAL_MATCH_DETAIL) || handler->detail == detail) &&
((mask & G_SIGNAL_MATCH_CLOSURE) || handler->closure == closure) &&
((mask & G_SIGNAL_MATCH_DATA) || handler->closure->data == data) &&
((mask & G_SIGNAL_MATCH_UNBLOCKED) || handler->block_count == 0) &&
((mask & G_SIGNAL_MATCH_FUNC) || (handler->closure->marshal == node->c_marshaller &&
G_REAL_CLOSURE (handler->closure)->meta_marshal == NULL &&
((GCClosure*) handler->closure)->callback == func)))
{
mlist = handler_match_prepend (mlist, handler, signal_id);
if (one_and_only)
return mlist;
}
}
else
{
GBSearchArray *hlbsa = g_hash_table_lookup (g_handler_list_bsa_ht, instance);
mask = ~mask;
if (hlbsa)
{
guint i;
for (i = 0; i < hlbsa->n_nodes; i++)
{
HandlerList *hlist = g_bsearch_array_get_nth (hlbsa, &g_signal_hlbsa_bconfig, i);
SignalNode *node = NULL;
Handler *handler;
if (!(mask & G_SIGNAL_MATCH_FUNC))
{
node = LOOKUP_SIGNAL_NODE (hlist->signal_id);
if (!node->c_marshaller)
continue;
}
for (handler = hlist->handlers; handler; handler = handler->next)
if (handler->sequential_number &&
((mask & G_SIGNAL_MATCH_DETAIL) || handler->detail == detail) &&
((mask & G_SIGNAL_MATCH_CLOSURE) || handler->closure == closure) &&
((mask & G_SIGNAL_MATCH_DATA) || handler->closure->data == data) &&
((mask & G_SIGNAL_MATCH_UNBLOCKED) || handler->block_count == 0) &&
((mask & G_SIGNAL_MATCH_FUNC) || (handler->closure->marshal == node->c_marshaller &&
G_REAL_CLOSURE (handler->closure)->meta_marshal == NULL &&
((GCClosure*) handler->closure)->callback == func)))
{
mlist = handler_match_prepend (mlist, handler, hlist->signal_id);
if (one_and_only)
return mlist;
}
}
}
}
return mlist;
}
static inline Handler*
handler_new (guint signal_id, gpointer instance, gboolean after)
{
Handler *handler = g_slice_new (Handler);
#ifndef G_DISABLE_CHECKS
if (g_handler_sequential_number < 1)
g_error (G_STRLOC ": handler id overflow, %s", REPORT_BUG);
#endif
handler->sequential_number = g_handler_sequential_number++;
handler->prev = NULL;
handler->next = NULL;
handler->detail = 0;
handler->signal_id = signal_id;
handler->instance = instance;
handler->ref_count = 1;
handler->block_count = 0;
handler->after = after != FALSE;
handler->closure = NULL;
handler->has_invalid_closure_notify = 0;
g_hash_table_add (g_handlers, handler);
return handler;
}
static inline void
handler_ref (Handler *handler)
{
g_return_if_fail (handler->ref_count > 0);
handler->ref_count++;
}
static inline void
handler_unref_R (guint signal_id,
gpointer instance,
Handler *handler)
{
g_return_if_fail (handler->ref_count > 0);
handler->ref_count--;
if (G_UNLIKELY (handler->ref_count == 0))
{
HandlerList *hlist = NULL;
if (handler->next)
handler->next->prev = handler->prev;
if (handler->prev) /* watch out for g_signal_handlers_destroy()! */
handler->prev->next = handler->next;
else
{
hlist = handler_list_lookup (signal_id, instance);
g_assert (hlist != NULL);
hlist->handlers = handler->next;
}
if (instance)
{
/* check if we are removing the handler pointed to by tail_before */
if (!handler->after && (!handler->next || handler->next->after))
{
if (!hlist)
hlist = handler_list_lookup (signal_id, instance);
if (hlist)
{
g_assert (hlist->tail_before == handler); /* paranoid */
hlist->tail_before = handler->prev;
}
}
/* check if we are removing the handler pointed to by tail_after */
if (!handler->next)
{
if (!hlist)
hlist = handler_list_lookup (signal_id, instance);
if (hlist)
{
g_assert (hlist->tail_after == handler); /* paranoid */
hlist->tail_after = handler->prev;
}
}
}
SIGNAL_UNLOCK ();
g_closure_unref (handler->closure);
SIGNAL_LOCK ();
g_slice_free (Handler, handler);
}
}
static void
handler_insert (guint signal_id,
gpointer instance,
Handler *handler)
{
HandlerList *hlist;
g_assert (handler->prev == NULL && handler->next == NULL); /* paranoid */
hlist = handler_list_ensure (signal_id, instance);
if (!hlist->handlers)
{
hlist->handlers = handler;
if (!handler->after)
hlist->tail_before = handler;
}
else if (handler->after)
{
handler->prev = hlist->tail_after;
hlist->tail_after->next = handler;
}
else
{
if (hlist->tail_before)
{
handler->next = hlist->tail_before->next;
if (handler->next)
handler->next->prev = handler;
handler->prev = hlist->tail_before;
hlist->tail_before->next = handler;
}
else /* insert !after handler into a list of only after handlers */
{
handler->next = hlist->handlers;
if (handler->next)
handler->next->prev = handler;
hlist->handlers = handler;
}
hlist->tail_before = handler;
}
if (!handler->next)
hlist->tail_after = handler;
}
static void
node_update_single_va_closure (SignalNode *node)
{
GClosure *closure = NULL;
gboolean is_after = FALSE;
/* Fast path single-handler without boxing the arguments in GValues */
if (G_TYPE_IS_OBJECT (node->itype) &&
(node->flags & (G_SIGNAL_MUST_COLLECT)) == 0 &&
(node->emission_hooks == NULL || node->emission_hooks->hooks == NULL))
{
GSignalFlags run_type;
ClassClosure * cc;
GBSearchArray *bsa = node->class_closure_bsa;
if (bsa == NULL || bsa->n_nodes == 0)
closure = SINGLE_VA_CLOSURE_EMPTY_MAGIC;
else if (bsa->n_nodes == 1)
{
/* Look for default class closure (can't support non-default as it
chains up using GValues */
cc = g_bsearch_array_get_nth (bsa, &g_class_closure_bconfig, 0);
if (cc->instance_type == 0)
{
run_type = node->flags & (G_SIGNAL_RUN_FIRST|G_SIGNAL_RUN_LAST|G_SIGNAL_RUN_CLEANUP);
/* Only support *one* of run-first or run-last, not multiple or cleanup */
if (run_type == G_SIGNAL_RUN_FIRST ||
run_type == G_SIGNAL_RUN_LAST)
{
closure = cc->closure;
is_after = (run_type == G_SIGNAL_RUN_LAST);
}
}
}
}
node->single_va_closure_is_valid = TRUE;
node->single_va_closure = closure;
node->single_va_closure_is_after = is_after;
}
static inline void
emission_push (Emission *emission)
{
emission->next = g_emissions;
g_emissions = emission;
}
static inline void
emission_pop (Emission *emission)
{
Emission *node, *last = NULL;
for (node = g_emissions; node; last = node, node = last->next)
if (node == emission)
{
if (last)
last->next = node->next;
else
g_emissions = node->next;
return;
}
g_assert_not_reached ();
}
static inline Emission*
emission_find (guint signal_id,
GQuark detail,
gpointer instance)
{
Emission *emission;
for (emission = g_emissions; emission; emission = emission->next)
if (emission->instance == instance &&
emission->ihint.signal_id == signal_id &&
emission->ihint.detail == detail)
return emission;
return NULL;
}
static inline Emission*
emission_find_innermost (gpointer instance)
{
Emission *emission;
for (emission = g_emissions; emission; emission = emission->next)
if (emission->instance == instance)
return emission;
return NULL;
}
static gint
signal_key_cmp (gconstpointer node1,
gconstpointer node2)
{
const SignalKey *key1 = node1, *key2 = node2;
if (key1->itype == key2->itype)
return G_BSEARCH_ARRAY_CMP (key1->quark, key2->quark);
else
return G_BSEARCH_ARRAY_CMP (key1->itype, key2->itype);
}
void
_g_signal_init (void)
{
SIGNAL_LOCK ();
if (!g_n_signal_nodes)
{
/* setup handler list binary searchable array hash table (in german, that'd be one word ;) */
g_handler_list_bsa_ht = g_hash_table_new (g_direct_hash, NULL);
g_signal_key_bsa = g_bsearch_array_create (&g_signal_key_bconfig);
/* invalid (0) signal_id */
g_n_signal_nodes = 1;
g_signal_nodes = g_renew (SignalNode*, g_signal_nodes, g_n_signal_nodes);
g_signal_nodes[0] = NULL;
g_handlers = g_hash_table_new (handler_hash, handler_equal);
}
SIGNAL_UNLOCK ();
}
void
_g_signals_destroy (GType itype)
{
guint i;
SIGNAL_LOCK ();
for (i = 1; i < g_n_signal_nodes; i++)
{
SignalNode *node = g_signal_nodes[i];
if (node->itype == itype)
{
if (node->destroyed)
g_critical (G_STRLOC ": signal \"%s\" of type '%s' already destroyed",
node->name,
type_debug_name (node->itype));
else
signal_destroy_R (node);
}
}
SIGNAL_UNLOCK ();
}
/**
* g_signal_stop_emission:
* @instance: (type GObject.Object): the object whose signal handlers you wish to stop.
* @signal_id: the signal identifier, as returned by g_signal_lookup().
* @detail: the detail which the signal was emitted with.
*
* Stops a signal's current emission.
*
* This will prevent the default method from running, if the signal was
* %G_SIGNAL_RUN_LAST and you connected normally (i.e. without the "after"
* flag).
*
* Prints a warning if used on a signal which isn't being emitted.
*/
void
g_signal_stop_emission (gpointer instance,
guint signal_id,
GQuark detail)
{
SignalNode *node;
g_return_if_fail (G_TYPE_CHECK_INSTANCE (instance));
g_return_if_fail (signal_id > 0);
SIGNAL_LOCK ();
node = LOOKUP_SIGNAL_NODE (signal_id);
if (node && detail && !(node->flags & G_SIGNAL_DETAILED))
{
g_critical ("%s: signal id '%u' does not support detail (%u)", G_STRLOC, signal_id, detail);
SIGNAL_UNLOCK ();
return;
}
if (node && g_type_is_a (G_TYPE_FROM_INSTANCE (instance), node->itype))
{
Emission *emission = emission_find (signal_id, detail, instance);
if (emission)
{
if (emission->state == EMISSION_HOOK)
g_critical (G_STRLOC ": emission of signal \"%s\" for instance '%p' cannot be stopped from emission hook",
node->name, instance);
else if (emission->state == EMISSION_RUN)
emission->state = EMISSION_STOP;
}
else
g_critical (G_STRLOC ": no emission of signal \"%s\" to stop for instance '%p'",
node->name, instance);
}
else
g_critical ("%s: signal id '%u' is invalid for instance '%p'", G_STRLOC, signal_id, instance);
SIGNAL_UNLOCK ();
}
static void
signal_finalize_hook (GHookList *hook_list,
GHook *hook)
{
GDestroyNotify destroy = hook->destroy;
if (destroy)
{
hook->destroy = NULL;
SIGNAL_UNLOCK ();
destroy (hook->data);
SIGNAL_LOCK ();
}
}
/**
* g_signal_add_emission_hook:
* @signal_id: the signal identifier, as returned by g_signal_lookup().
* @detail: the detail on which to call the hook.
* @hook_func: (not nullable): a #GSignalEmissionHook function.
* @hook_data: (nullable) (closure hook_func): user data for @hook_func.
* @data_destroy: (nullable) (destroy hook_data): a #GDestroyNotify for @hook_data.
*
* Adds an emission hook for a signal, which will get called for any emission
* of that signal, independent of the instance. This is possible only
* for signals which don't have %G_SIGNAL_NO_HOOKS flag set.
*
* Returns: the hook id, for later use with g_signal_remove_emission_hook().
*/
gulong
g_signal_add_emission_hook (guint signal_id,
GQuark detail,
GSignalEmissionHook hook_func,
gpointer hook_data,
GDestroyNotify data_destroy)
{
static gulong seq_hook_id = 1;
SignalNode *node;
GHook *hook;
SignalHook *signal_hook;
g_return_val_if_fail (signal_id > 0, 0);
g_return_val_if_fail (hook_func != NULL, 0);
SIGNAL_LOCK ();
node = LOOKUP_SIGNAL_NODE (signal_id);
if (!node || node->destroyed)
{
g_critical ("%s: invalid signal id '%u'", G_STRLOC, signal_id);
SIGNAL_UNLOCK ();
return 0;
}
if (node->flags & G_SIGNAL_NO_HOOKS)
{
g_critical ("%s: signal id '%u' does not support emission hooks (G_SIGNAL_NO_HOOKS flag set)", G_STRLOC, signal_id);
SIGNAL_UNLOCK ();
return 0;
}
if (detail && !(node->flags & G_SIGNAL_DETAILED))
{
g_critical ("%s: signal id '%u' does not support detail (%u)", G_STRLOC, signal_id, detail);
SIGNAL_UNLOCK ();
return 0;
}
node->single_va_closure_is_valid = FALSE;
if (!node->emission_hooks)
{
node->emission_hooks = g_new (GHookList, 1);
g_hook_list_init (node->emission_hooks, sizeof (SignalHook));
node->emission_hooks->finalize_hook = signal_finalize_hook;
}
node_check_deprecated (node);
hook = g_hook_alloc (node->emission_hooks);
hook->data = hook_data;
hook->func = (gpointer) hook_func;
hook->destroy = data_destroy;
signal_hook = SIGNAL_HOOK (hook);
signal_hook->detail = detail;
node->emission_hooks->seq_id = seq_hook_id;
g_hook_append (node->emission_hooks, hook);
seq_hook_id = node->emission_hooks->seq_id;
SIGNAL_UNLOCK ();
return hook->hook_id;
}
/**
* g_signal_remove_emission_hook:
* @signal_id: the id of the signal
* @hook_id: the id of the emission hook, as returned by
* g_signal_add_emission_hook()
*
* Deletes an emission hook.
*/
void
g_signal_remove_emission_hook (guint signal_id,
gulong hook_id)
{
SignalNode *node;
g_return_if_fail (signal_id > 0);
g_return_if_fail (hook_id > 0);
SIGNAL_LOCK ();
node = LOOKUP_SIGNAL_NODE (signal_id);
if (!node || node->destroyed)
{
g_critical ("%s: invalid signal id '%u'", G_STRLOC, signal_id);
goto out;
}
else if (!node->emission_hooks || !g_hook_destroy (node->emission_hooks, hook_id))
g_critical ("%s: signal \"%s\" had no hook (%lu) to remove", G_STRLOC, node->name, hook_id);
node->single_va_closure_is_valid = FALSE;
out:
SIGNAL_UNLOCK ();
}
static inline guint
signal_parse_name (const gchar *name,
GType itype,
GQuark *detail_p,
gboolean force_quark)
{
const gchar *colon = strchr (name, ':');
guint signal_id;
if (!colon)
{
signal_id = signal_id_lookup (name, itype);
if (signal_id && detail_p)
*detail_p = 0;
}
else if (colon[1] == ':')
{
gchar buffer[32];
guint l = colon - name;
if (colon[2] == '\0')
return 0;
if (l < 32)
{
memcpy (buffer, name, l);
buffer[l] = 0;
signal_id = signal_id_lookup (buffer, itype);
}
else
{
gchar *signal = g_new (gchar, l + 1);
memcpy (signal, name, l);
signal[l] = 0;
signal_id = signal_id_lookup (signal, itype);
g_free (signal);
}
if (signal_id && detail_p)
*detail_p = (force_quark ? g_quark_from_string : g_quark_try_string) (colon + 2);
}
else
signal_id = 0;
return signal_id;
}
/**
* g_signal_parse_name:
* @detailed_signal: a string of the form "signal-name::detail".
* @itype: The interface/instance type that introduced "signal-name".
* @signal_id_p: (out): Location to store the signal id.
* @detail_p: (out): Location to store the detail quark.
* @force_detail_quark: %TRUE forces creation of a #GQuark for the detail.
*
* Internal function to parse a signal name into its @signal_id
* and @detail quark.
*
* Returns: Whether the signal name could successfully be parsed and @signal_id_p and @detail_p contain valid return values.
*/
gboolean
g_signal_parse_name (const gchar *detailed_signal,
GType itype,
guint *signal_id_p,
GQuark *detail_p,
gboolean force_detail_quark)
{
SignalNode *node;
GQuark detail = 0;
guint signal_id;
g_return_val_if_fail (detailed_signal != NULL, FALSE);
g_return_val_if_fail (G_TYPE_IS_INSTANTIATABLE (itype) || G_TYPE_IS_INTERFACE (itype), FALSE);
SIGNAL_LOCK ();
signal_id = signal_parse_name (detailed_signal, itype, &detail, force_detail_quark);
node = signal_id ? LOOKUP_SIGNAL_NODE (signal_id) : NULL;
if (!node || node->destroyed ||
(detail && !(node->flags & G_SIGNAL_DETAILED)))
{
SIGNAL_UNLOCK ();
return FALSE;
}
SIGNAL_UNLOCK ();
if (signal_id_p)
*signal_id_p = signal_id;
if (detail_p)
*detail_p = detail;
return TRUE;
}
/**
* g_signal_stop_emission_by_name:
* @instance: (type GObject.Object): the object whose signal handlers you wish to stop.
* @detailed_signal: a string of the form "signal-name::detail".
*
* Stops a signal's current emission.
*
* This is just like g_signal_stop_emission() except it will look up the
* signal id for you.
*/
void
g_signal_stop_emission_by_name (gpointer instance,
const gchar *detailed_signal)
{
guint signal_id;
GQuark detail = 0;
GType itype;
g_return_if_fail (G_TYPE_CHECK_INSTANCE (instance));
g_return_if_fail (detailed_signal != NULL);
SIGNAL_LOCK ();
itype = G_TYPE_FROM_INSTANCE (instance);
signal_id = signal_parse_name (detailed_signal, itype, &detail, TRUE);
if (signal_id)
{
SignalNode *node = LOOKUP_SIGNAL_NODE (signal_id);
if (detail && !(node->flags & G_SIGNAL_DETAILED))
g_critical ("%s: signal '%s' does not support details", G_STRLOC, detailed_signal);
else if (!g_type_is_a (itype, node->itype))
g_critical ("%s: signal '%s' is invalid for instance '%p' of type '%s'",
G_STRLOC, detailed_signal, instance, g_type_name (itype));
else
{
Emission *emission = emission_find (signal_id, detail, instance);
if (emission)
{
if (emission->state == EMISSION_HOOK)
g_critical (G_STRLOC ": emission of signal \"%s\" for instance '%p' cannot be stopped from emission hook",
node->name, instance);
else if (emission->state == EMISSION_RUN)
emission->state = EMISSION_STOP;
}
else
g_critical (G_STRLOC ": no emission of signal \"%s\" to stop for instance '%p'",
node->name, instance);
}
}
else
g_critical ("%s: signal '%s' is invalid for instance '%p' of type '%s'",
G_STRLOC, detailed_signal, instance, g_type_name (itype));
SIGNAL_UNLOCK ();
}
/**
* g_signal_lookup:
* @name: the signal's name.
* @itype: the type that the signal operates on.
*
* Given the name of the signal and the type of object it connects to, gets
* the signal's identifying integer. Emitting the signal by number is
* somewhat faster than using the name each time.
*
* Also tries the ancestors of the given type.
*
* The type class passed as @itype must already have been instantiated (for
* example, using g_type_class_ref()) for this function to work, as signals are
* always installed during class initialization.
*
* See g_signal_new() for details on allowed signal names.
*
* Returns: the signal's identifying number, or 0 if no signal was found.
*/
guint
g_signal_lookup (const gchar *name,
GType itype)
{
guint signal_id;
g_return_val_if_fail (name != NULL, 0);
g_return_val_if_fail (G_TYPE_IS_INSTANTIATABLE (itype) || G_TYPE_IS_INTERFACE (itype), 0);
SIGNAL_LOCK ();
signal_id = signal_id_lookup (name, itype);
SIGNAL_UNLOCK ();
if (!signal_id)
{
/* give elaborate warnings */
if (!g_type_name (itype))
g_critical (G_STRLOC ": unable to look up signal \"%s\" for invalid type id '%"G_GSIZE_FORMAT"'",
name, itype);
else if (!g_signal_is_valid_name (name))
g_critical (G_STRLOC ": unable to look up invalid signal name \"%s\" on type '%s'",
name, g_type_name (itype));
}
return signal_id;
}
/**
* g_signal_list_ids:
* @itype: Instance or interface type.
* @n_ids: Location to store the number of signal ids for @itype.
*
* Lists the signals by id that a certain instance or interface type
* created. Further information about the signals can be acquired through
* g_signal_query().
*
* Returns: (array length=n_ids) (transfer full): Newly allocated array of signal IDs.
*/
guint*
g_signal_list_ids (GType itype,
guint *n_ids)
{
SignalKey *keys;
GArray *result;
guint n_nodes;
guint i;
g_return_val_if_fail (G_TYPE_IS_INSTANTIATABLE (itype) || G_TYPE_IS_INTERFACE (itype), NULL);
g_return_val_if_fail (n_ids != NULL, NULL);
SIGNAL_LOCK ();
keys = g_bsearch_array_get_nth (g_signal_key_bsa, &g_signal_key_bconfig, 0);
n_nodes = g_bsearch_array_get_n_nodes (g_signal_key_bsa);
result = g_array_new (FALSE, FALSE, sizeof (guint));
for (i = 0; i < n_nodes; i++)
if (keys[i].itype == itype)
{
g_array_append_val (result, keys[i].signal_id);
}
*n_ids = result->len;
SIGNAL_UNLOCK ();
if (!n_nodes)
{
/* give elaborate warnings */
if (!g_type_name (itype))
g_critical (G_STRLOC ": unable to list signals for invalid type id '%"G_GSIZE_FORMAT"'",
itype);
else if (!G_TYPE_IS_INSTANTIATABLE (itype) && !G_TYPE_IS_INTERFACE (itype))
g_critical (G_STRLOC ": unable to list signals of non instantiatable type '%s'",
g_type_name (itype));
else if (!g_type_class_peek (itype) && !G_TYPE_IS_INTERFACE (itype))
g_critical (G_STRLOC ": unable to list signals of unloaded type '%s'",
g_type_name (itype));
}
return (guint*) g_array_free (result, FALSE);
}
/**
* g_signal_name:
* @signal_id: the signal's identifying number.
*
* Given the signal's identifier, finds its name.
*
* Two different signals may have the same name, if they have differing types.
*
* Returns: (nullable): the signal name, or %NULL if the signal number was invalid.
*/
const gchar *
g_signal_name (guint signal_id)
{
SignalNode *node;
const gchar *name;
SIGNAL_LOCK ();
node = LOOKUP_SIGNAL_NODE (signal_id);
name = node ? node->name : NULL;
SIGNAL_UNLOCK ();
return (char*) name;
}
/**
* g_signal_query:
* @signal_id: The signal id of the signal to query information for.
* @query: (out caller-allocates) (not optional): A user provided structure that is
* filled in with constant values upon success.
*
* Queries the signal system for in-depth information about a
* specific signal. This function will fill in a user-provided
* structure to hold signal-specific information. If an invalid
* signal id is passed in, the @signal_id member of the #GSignalQuery
* is 0. All members filled into the #GSignalQuery structure should
* be considered constant and have to be left untouched.
*/
void
g_signal_query (guint signal_id,
GSignalQuery *query)
{
SignalNode *node;
g_return_if_fail (query != NULL);
SIGNAL_LOCK ();
node = LOOKUP_SIGNAL_NODE (signal_id);
if (!node || node->destroyed)
query->signal_id = 0;
else
{
query->signal_id = node->signal_id;
query->signal_name = node->name;
query->itype = node->itype;
query->signal_flags = node->flags;
query->return_type = node->return_type;
query->n_params = node->n_params;
query->param_types = node->param_types;
}
SIGNAL_UNLOCK ();
}
/**
* g_signal_new:
* @signal_name: the name for the signal
* @itype: the type this signal pertains to. It will also pertain to
* types which are derived from this type.
* @signal_flags: a combination of #GSignalFlags specifying detail of when
* the default handler is to be invoked. You should at least specify
* %G_SIGNAL_RUN_FIRST or %G_SIGNAL_RUN_LAST.
* @class_offset: The offset of the function pointer in the class structure
* for this type. Used to invoke a class method generically. Pass 0 to
* not associate a class method slot with this signal.
* @accumulator: (nullable): the accumulator for this signal; may be %NULL.
* @accu_data: (nullable) (closure accumulator): user data for the @accumulator.
* @c_marshaller: (nullable): the function to translate arrays of parameter
* values to signal emissions into C language callback invocations or %NULL.
* @return_type: the type of return value, or %G_TYPE_NONE for a signal
* without a return value.
* @n_params: the number of parameter types to follow.
* @...: a list of types, one for each parameter.
*
* Creates a new signal. (This is usually done in the class initializer.)
*
* A signal name consists of segments consisting of ASCII letters and
* digits, separated by either the `-` or `_` character. The first
* character of a signal name must be a letter. Names which violate these
* rules lead to undefined behaviour. These are the same rules as for property
* naming (see g_param_spec_internal()).
*
* When registering a signal and looking up a signal, either separator can
* be used, but they cannot be mixed. Using `-` is considerably more efficient.
* Using `_` is discouraged.
*
* If 0 is used for @class_offset subclasses cannot override the class handler
* in their class_init method by doing super_class->signal_handler = my_signal_handler.
* Instead they will have to use g_signal_override_class_handler().
*
* If @c_marshaller is %NULL, g_cclosure_marshal_generic() will be used as
* the marshaller for this signal. In some simple cases, g_signal_new()
* will use a more optimized c_marshaller and va_marshaller for the signal
* instead of g_cclosure_marshal_generic().
*
* If @c_marshaller is non-%NULL, you need to also specify a va_marshaller
* using g_signal_set_va_marshaller() or the generic va_marshaller will
* be used.
*
* Returns: the signal id
*/
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,
...)
{
va_list args;
guint signal_id;
g_return_val_if_fail (signal_name != NULL, 0);
va_start (args, n_params);
signal_id = g_signal_new_valist (signal_name, itype, signal_flags,
class_offset ? g_signal_type_cclosure_new (itype, class_offset) : NULL,
accumulator, accu_data, c_marshaller,
return_type, n_params, args);
va_end (args);
return signal_id;
}
/**
* g_signal_new_class_handler:
* @signal_name: the name for the signal
* @itype: the type this signal pertains to. It will also pertain to
* types which are derived from this type.
* @signal_flags: a combination of #GSignalFlags specifying detail of when
* the default handler is to be invoked. You should at least specify
* %G_SIGNAL_RUN_FIRST or %G_SIGNAL_RUN_LAST.
* @class_handler: (nullable): a #GCallback which acts as class implementation of
* this signal. Used to invoke a class method generically. Pass %NULL to
* not associate a class method with this signal.
* @accumulator: (nullable): the accumulator for this signal; may be %NULL.
* @accu_data: (nullable) (closure accumulator): user data for the @accumulator.
* @c_marshaller: (nullable): the function to translate arrays of parameter
* values to signal emissions into C language callback invocations or %NULL.
* @return_type: the type of return value, or %G_TYPE_NONE for a signal
* without a return value.
* @n_params: the number of parameter types to follow.
* @...: a list of types, one for each parameter.
*
* Creates a new signal. (This is usually done in the class initializer.)
*
* This is a variant of g_signal_new() that takes a C callback instead
* of a class offset for the signal's class handler. This function
* doesn't need a function pointer exposed in the class structure of
* an object definition, instead the function pointer is passed
* directly and can be overridden by derived classes with
* g_signal_override_class_closure() or
* g_signal_override_class_handler() and chained to with
* g_signal_chain_from_overridden() or
* g_signal_chain_from_overridden_handler().
*
* See g_signal_new() for information about signal names.
*
* If c_marshaller is %NULL, g_cclosure_marshal_generic() will be used as
* the marshaller for this signal.
*
* Returns: the signal id
*
* Since: 2.18
*/
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,
...)
{
va_list args;
guint signal_id;
g_return_val_if_fail (signal_name != NULL, 0);
va_start (args, n_params);
signal_id = g_signal_new_valist (signal_name, itype, signal_flags,
class_handler ? g_cclosure_new (class_handler, NULL, NULL) : NULL,
accumulator, accu_data, c_marshaller,
return_type, n_params, args);
va_end (args);
return signal_id;
}
static inline ClassClosure*
signal_find_class_closure (SignalNode *node,
GType itype)
{
GBSearchArray *bsa = node->class_closure_bsa;
ClassClosure *cc;
if (bsa)
{
ClassClosure key;
/* cc->instance_type is 0 for default closure */
if (g_bsearch_array_get_n_nodes (bsa) == 1)
{
cc = g_bsearch_array_get_nth (bsa, &g_class_closure_bconfig, 0);
if (cc && cc->instance_type == 0) /* check for default closure */
return cc;
}
key.instance_type = itype;
cc = g_bsearch_array_lookup (bsa, &g_class_closure_bconfig, &key);
while (!cc && key.instance_type)
{
key.instance_type = g_type_parent (key.instance_type);
cc = g_bsearch_array_lookup (bsa, &g_class_closure_bconfig, &key);
}
}
else
cc = NULL;
return cc;
}
static inline GClosure*
signal_lookup_closure (SignalNode *node,
GTypeInstance *instance)
{
ClassClosure *cc;
cc = signal_find_class_closure (node, G_TYPE_FROM_INSTANCE (instance));
return cc ? cc->closure : NULL;
}
static void
signal_add_class_closure (SignalNode *node,
GType itype,
GClosure *closure)
{
ClassClosure key;
node->single_va_closure_is_valid = FALSE;
if (!node->class_closure_bsa)
node->class_closure_bsa = g_bsearch_array_create (&g_class_closure_bconfig);
key.instance_type = itype;
key.closure = g_closure_ref (closure);
node->class_closure_bsa = g_bsearch_array_insert (node->class_closure_bsa,
&g_class_closure_bconfig,
&key);
g_closure_sink (closure);
if (node->c_marshaller && closure && G_CLOSURE_NEEDS_MARSHAL (closure))
{
g_closure_set_marshal (closure, node->c_marshaller);
if (node->va_marshaller)
_g_closure_set_va_marshal (closure, node->va_marshaller);
}
}
/**
* g_signal_newv:
* @signal_name: the name for the signal
* @itype: the type this signal pertains to. It will also pertain to
* types which are derived from this type
* @signal_flags: a combination of #GSignalFlags specifying detail of when
* the default handler is to be invoked. You should at least specify
* %G_SIGNAL_RUN_FIRST or %G_SIGNAL_RUN_LAST
* @class_closure: (nullable): The closure to invoke on signal emission;
* may be %NULL
* @accumulator: (nullable): the accumulator for this signal; may be %NULL
* @accu_data: (nullable) (closure accumulator): user data for the @accumulator
* @c_marshaller: (nullable): the function to translate arrays of
* parameter values to signal emissions into C language callback
* invocations or %NULL
* @return_type: the type of return value, or %G_TYPE_NONE for a signal
* without a return value
* @n_params: the length of @param_types
* @param_types: (array length=n_params) (nullable): an array of types, one for
* each parameter (may be %NULL if @n_params is zero)
*
* Creates a new signal. (This is usually done in the class initializer.)
*
* See g_signal_new() for details on allowed signal names.
*
* If c_marshaller is %NULL, g_cclosure_marshal_generic() will be used as
* the marshaller for this signal.
*
* Returns: the signal id
*/
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)
{
const gchar *name;
gchar *signal_name_copy = NULL;
guint signal_id, i;
SignalNode *node;
GSignalCMarshaller builtin_c_marshaller;
GSignalCVaMarshaller builtin_va_marshaller;
GSignalCVaMarshaller va_marshaller;
g_return_val_if_fail (signal_name != NULL, 0);
g_return_val_if_fail (g_signal_is_valid_name (signal_name), 0);
g_return_val_if_fail (G_TYPE_IS_INSTANTIATABLE (itype) || G_TYPE_IS_INTERFACE (itype), 0);
if (n_params)
g_return_val_if_fail (param_types != NULL, 0);
g_return_val_if_fail ((return_type & G_SIGNAL_TYPE_STATIC_SCOPE) == 0, 0);
if (return_type == (G_TYPE_NONE & ~G_SIGNAL_TYPE_STATIC_SCOPE))
g_return_val_if_fail (accumulator == NULL, 0);
if (!accumulator)
g_return_val_if_fail (accu_data == NULL, 0);
g_return_val_if_fail ((signal_flags & G_SIGNAL_ACCUMULATOR_FIRST_RUN) == 0, 0);
if (!is_canonical (signal_name))
{
signal_name_copy = g_strdup (signal_name);
canonicalize_key (signal_name_copy);
name = signal_name_copy;
}
else
{
name = signal_name;
}
SIGNAL_LOCK ();
signal_id = signal_id_lookup (name, itype);
node = LOOKUP_SIGNAL_NODE (signal_id);
if (node && !node->destroyed)
{
g_critical (G_STRLOC ": signal \"%s\" already exists in the '%s' %s",
name,
type_debug_name (node->itype),
G_TYPE_IS_INTERFACE (node->itype) ? "interface" : "class ancestry");
g_free (signal_name_copy);
SIGNAL_UNLOCK ();
return 0;
}
if (node && node->itype != itype)
{
g_critical (G_STRLOC ": signal \"%s\" for type '%s' was previously created for type '%s'",
name,
type_debug_name (itype),
type_debug_name (node->itype));
g_free (signal_name_copy);
SIGNAL_UNLOCK ();
return 0;
}
for (i = 0; i < n_params; i++)
if (!G_TYPE_IS_VALUE (param_types[i] & ~G_SIGNAL_TYPE_STATIC_SCOPE))
{
g_critical (G_STRLOC ": parameter %d of type '%s' for signal \"%s::%s\" is not a value type",
i + 1, type_debug_name (param_types[i]), type_debug_name (itype), name);
g_free (signal_name_copy);
SIGNAL_UNLOCK ();
return 0;
}
if (return_type != G_TYPE_NONE && !G_TYPE_IS_VALUE (return_type & ~G_SIGNAL_TYPE_STATIC_SCOPE))
{
g_critical (G_STRLOC ": return value of type '%s' for signal \"%s::%s\" is not a value type",
type_debug_name (return_type), type_debug_name (itype), name);
g_free (signal_name_copy);
SIGNAL_UNLOCK ();
return 0;
}
/* setup permanent portion of signal node */
if (!node)
{
SignalKey key;
signal_id = g_n_signal_nodes++;
node = g_new (SignalNode, 1);
node->signal_id = signal_id;
g_signal_nodes = g_renew (SignalNode*, g_signal_nodes, g_n_signal_nodes);
g_signal_nodes[signal_id] = node;
node->itype = itype;
key.itype = itype;
key.signal_id = signal_id;
node->name = g_intern_string (name);
key.quark = g_quark_from_string (name);
g_signal_key_bsa = g_bsearch_array_insert (g_signal_key_bsa, &g_signal_key_bconfig, &key);
TRACE(GOBJECT_SIGNAL_NEW(signal_id, name, itype));
}
node->destroyed = FALSE;
/* setup reinitializable portion */
node->single_va_closure_is_valid = FALSE;
node->flags = signal_flags & G_SIGNAL_FLAGS_MASK;
node->n_params = n_params;
node->param_types = g_memdup2 (param_types, sizeof (GType) * n_params);
node->return_type = return_type;
node->class_closure_bsa = NULL;
if (accumulator)
{
node->accumulator = g_new (SignalAccumulator, 1);
node->accumulator->func = accumulator;
node->accumulator->data = accu_data;
}
else
node->accumulator = NULL;
builtin_c_marshaller = NULL;
builtin_va_marshaller = NULL;
/* Pick up built-in va marshallers for standard types, and
instead of generic marshaller if no marshaller specified */
if (n_params == 0 && return_type == G_TYPE_NONE)
{
builtin_c_marshaller = g_cclosure_marshal_VOID__VOID;
builtin_va_marshaller = g_cclosure_marshal_VOID__VOIDv;
}
else if (n_params == 1 && return_type == G_TYPE_NONE)
{
#define ADD_CHECK(__type__) \
else if (g_type_is_a (param_types[0] & ~G_SIGNAL_TYPE_STATIC_SCOPE, G_TYPE_ ##__type__)) \
{ \
builtin_c_marshaller = g_cclosure_marshal_VOID__ ## __type__; \
builtin_va_marshaller = g_cclosure_marshal_VOID__ ## __type__ ##v; \
}
if (0) {}
ADD_CHECK (BOOLEAN)
ADD_CHECK (CHAR)
ADD_CHECK (UCHAR)
ADD_CHECK (INT)
ADD_CHECK (UINT)
ADD_CHECK (LONG)
ADD_CHECK (ULONG)
ADD_CHECK (ENUM)
ADD_CHECK (FLAGS)
ADD_CHECK (FLOAT)
ADD_CHECK (DOUBLE)
ADD_CHECK (STRING)
ADD_CHECK (PARAM)
ADD_CHECK (BOXED)
ADD_CHECK (POINTER)
ADD_CHECK (OBJECT)
ADD_CHECK (VARIANT)
}
if (c_marshaller == NULL)
{
if (builtin_c_marshaller)
{
c_marshaller = builtin_c_marshaller;
va_marshaller = builtin_va_marshaller;
}
else
{
c_marshaller = g_cclosure_marshal_generic;
va_marshaller = g_cclosure_marshal_generic_va;
}
}
else
va_marshaller = NULL;
node->c_marshaller = c_marshaller;
node->va_marshaller = va_marshaller;
node->emission_hooks = NULL;
if (class_closure)
signal_add_class_closure (node, 0, class_closure);
SIGNAL_UNLOCK ();
g_free (signal_name_copy);
return signal_id;
}
/**
* g_signal_set_va_marshaller:
* @signal_id: the signal id
* @instance_type: the instance type on which to set the marshaller.
* @va_marshaller: the marshaller to set.
*
* Change the #GSignalCVaMarshaller used for a given signal. This is a
* specialised form of the marshaller that can often be used for the
* common case of a single connected signal handler and avoids the
* overhead of #GValue. Its use is optional.
*
* Since: 2.32
*/
void
g_signal_set_va_marshaller (guint signal_id,
GType instance_type,
GSignalCVaMarshaller va_marshaller)
{
SignalNode *node;
g_return_if_fail (signal_id > 0);
g_return_if_fail (va_marshaller != NULL);
SIGNAL_LOCK ();
node = LOOKUP_SIGNAL_NODE (signal_id);
if (node)
{
node->va_marshaller = va_marshaller;
if (node->class_closure_bsa)
{
ClassClosure *cc = g_bsearch_array_get_nth (node->class_closure_bsa, &g_class_closure_bconfig, 0);
if (cc->closure->marshal == node->c_marshaller)
_g_closure_set_va_marshal (cc->closure, va_marshaller);
}
node->single_va_closure_is_valid = FALSE;
}
SIGNAL_UNLOCK ();
}
/**
* g_signal_new_valist:
* @signal_name: the name for the signal
* @itype: the type this signal pertains to. It will also pertain to
* types which are derived from this type.
* @signal_flags: a combination of #GSignalFlags specifying detail of when
* the default handler is to be invoked. You should at least specify
* %G_SIGNAL_RUN_FIRST or %G_SIGNAL_RUN_LAST.
* @class_closure: (nullable): The closure to invoke on signal emission; may be %NULL.
* @accumulator: (nullable): the accumulator for this signal; may be %NULL.
* @accu_data: (nullable) (closure accumulator): user data for the @accumulator.
* @c_marshaller: (nullable): the function to translate arrays of parameter
* values to signal emissions into C language callback invocations or %NULL.
* @return_type: the type of return value, or %G_TYPE_NONE for a signal
* without a return value.
* @n_params: the number of parameter types in @args.
* @args: va_list of #GType, one for each parameter.
*
* Creates a new signal. (This is usually done in the class initializer.)
*
* See g_signal_new() for details on allowed signal names.
*
* If c_marshaller is %NULL, g_cclosure_marshal_generic() will be used as
* the marshaller for this signal.
*
* Returns: the signal id
*/
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)
{
/* Somewhat arbitrarily reserve 200 bytes. That should cover the majority
* of cases where n_params is small and still be small enough for what we
* want to put on the stack. */
GType param_types_stack[200 / sizeof (GType)];
GType *param_types_heap = NULL;
GType *param_types;
guint i;
guint signal_id;
param_types = param_types_stack;
if (n_params > 0)
{
if (G_UNLIKELY (n_params > G_N_ELEMENTS (param_types_stack)))
{
param_types_heap = g_new (GType, n_params);
param_types = param_types_heap;
}
for (i = 0; i < n_params; i++)
param_types[i] = va_arg (args, GType);
}
signal_id = g_signal_newv (signal_name, itype, signal_flags,
class_closure, accumulator, accu_data, c_marshaller,
return_type, n_params, param_types);
g_free (param_types_heap);
return signal_id;
}
static void
signal_destroy_R (SignalNode *signal_node)
{
SignalNode node = *signal_node;
signal_node->destroyed = TRUE;
/* reentrancy caution, zero out real contents first */
signal_node->single_va_closure_is_valid = FALSE;
signal_node->n_params = 0;
signal_node->param_types = NULL;
signal_node->return_type = 0;
signal_node->class_closure_bsa = NULL;
signal_node->accumulator = NULL;
signal_node->c_marshaller = NULL;
signal_node->va_marshaller = NULL;
signal_node->emission_hooks = NULL;
#ifdef G_ENABLE_DEBUG
/* check current emissions */
{
Emission *emission;
for (emission = g_emissions; emission; emission = emission->next)
if (emission->ihint.signal_id == node.signal_id)
g_critical (G_STRLOC ": signal \"%s\" being destroyed is currently in emission (instance '%p')",
node.name, emission->instance);
}
#endif
/* free contents that need to
*/
SIGNAL_UNLOCK ();
g_free (node.param_types);
if (node.class_closure_bsa)
{
guint i;
for (i = 0; i < node.class_closure_bsa->n_nodes; i++)
{
ClassClosure *cc = g_bsearch_array_get_nth (node.class_closure_bsa, &g_class_closure_bconfig, i);
g_closure_unref (cc->closure);
}
g_bsearch_array_free (node.class_closure_bsa, &g_class_closure_bconfig);
}
g_free (node.accumulator);
if (node.emission_hooks)
{
g_hook_list_clear (node.emission_hooks);
g_free (node.emission_hooks);
}
SIGNAL_LOCK ();
}
/**
* g_signal_override_class_closure:
* @signal_id: the signal id
* @instance_type: the instance type on which to override the class closure
* for the signal.
* @class_closure: the closure.
*
* Overrides the class closure (i.e. the default handler) for the given signal
* for emissions on instances of @instance_type. @instance_type must be derived
* from the type to which the signal belongs.
*
* See g_signal_chain_from_overridden() and
* g_signal_chain_from_overridden_handler() for how to chain up to the
* parent class closure from inside the overridden one.
*/
void
g_signal_override_class_closure (guint signal_id,
GType instance_type,
GClosure *class_closure)
{
SignalNode *node;
g_return_if_fail (signal_id > 0);
g_return_if_fail (class_closure != NULL);
SIGNAL_LOCK ();
node = LOOKUP_SIGNAL_NODE (signal_id);
node_check_deprecated (node);
if (!g_type_is_a (instance_type, node->itype))
g_critical ("%s: type '%s' cannot be overridden for signal id '%u'", G_STRLOC, type_debug_name (instance_type), signal_id);
else
{
ClassClosure *cc = signal_find_class_closure (node, instance_type);
if (cc && cc->instance_type == instance_type)
g_critical ("%s: type '%s' is already overridden for signal id '%u'", G_STRLOC, type_debug_name (instance_type), signal_id);
else
signal_add_class_closure (node, instance_type, class_closure);
}
SIGNAL_UNLOCK ();
}
/**
* g_signal_override_class_handler:
* @signal_name: the name for the signal
* @instance_type: the instance type on which to override the class handler
* for the signal.
* @class_handler: the handler.
*
* Overrides the class closure (i.e. the default handler) for the
* given signal for emissions on instances of @instance_type with
* callback @class_handler. @instance_type must be derived from the
* type to which the signal belongs.
*
* See g_signal_chain_from_overridden() and
* g_signal_chain_from_overridden_handler() for how to chain up to the
* parent class closure from inside the overridden one.
*
* Since: 2.18
*/
void
g_signal_override_class_handler (const gchar *signal_name,
GType instance_type,
GCallback class_handler)
{
guint signal_id;
g_return_if_fail (signal_name != NULL);
g_return_if_fail (instance_type != G_TYPE_NONE);
g_return_if_fail (class_handler != NULL);
signal_id = g_signal_lookup (signal_name, instance_type);
if (signal_id)
g_signal_override_class_closure (signal_id, instance_type,
g_cclosure_new (class_handler, NULL, NULL));
else
g_critical ("%s: signal name '%s' is invalid for type id '%"G_GSIZE_FORMAT"'",
G_STRLOC, signal_name, instance_type);
}
/**
* g_signal_chain_from_overridden:
* @instance_and_params: (array) the argument list of the signal emission.
* The first element in the array is a #GValue for the instance the signal
* is being emitted on. The rest are any arguments to be passed to the signal.
* @return_value: Location for the return value.
*
* Calls the original class closure of a signal. This function should only
* be called from an overridden class closure; see
* g_signal_override_class_closure() and
* g_signal_override_class_handler().
*/
void
g_signal_chain_from_overridden (const GValue *instance_and_params,
GValue *return_value)
{
GType chain_type = 0, restore_type = 0;
Emission *emission = NULL;
GClosure *closure = NULL;
guint n_params = 0;
gpointer instance;
g_return_if_fail (instance_and_params != NULL);
instance = g_value_peek_pointer (instance_and_params);
g_return_if_fail (G_TYPE_CHECK_INSTANCE (instance));
SIGNAL_LOCK ();
emission = emission_find_innermost (instance);
if (emission)
{
SignalNode *node = LOOKUP_SIGNAL_NODE (emission->ihint.signal_id);
g_assert (node != NULL); /* paranoid */
/* we should probably do the same parameter checks as g_signal_emit() here.
*/
if (emission->chain_type != G_TYPE_NONE)
{
ClassClosure *cc = signal_find_class_closure (node, emission->chain_type);
g_assert (cc != NULL); /* closure currently in call stack */
n_params = node->n_params;
restore_type = cc->instance_type;
cc = signal_find_class_closure (node, g_type_parent (cc->instance_type));
if (cc && cc->instance_type != restore_type)
{
closure = cc->closure;
chain_type = cc->instance_type;
}
}
else
g_critical ("%s: signal id '%u' cannot be chained from current emission stage for instance '%p'", G_STRLOC, node->signal_id, instance);
}
else
g_critical ("%s: no signal is currently being emitted for instance '%p'", G_STRLOC, instance);
if (closure)
{
emission->chain_type = chain_type;
SIGNAL_UNLOCK ();
g_closure_invoke (closure,
return_value,
n_params + 1,
instance_and_params,
&emission->ihint);
SIGNAL_LOCK ();
emission->chain_type = restore_type;
}
SIGNAL_UNLOCK ();
}
/**
* g_signal_chain_from_overridden_handler: (skip)
* @instance: (type GObject.TypeInstance): the instance the signal is being
* emitted on.
* @...: parameters to be passed to the parent class closure, followed by a
* location for the return value. If the return type of the signal
* is %G_TYPE_NONE, the return value location can be omitted.
*
* Calls the original class closure of a signal. This function should
* only be called from an overridden class closure; see
* g_signal_override_class_closure() and
* g_signal_override_class_handler().
*
* Since: 2.18
*/
void
g_signal_chain_from_overridden_handler (gpointer instance,
...)
{
GType chain_type = 0, restore_type = 0;
Emission *emission = NULL;
GClosure *closure = NULL;
SignalNode *node = NULL;
guint n_params = 0;
g_return_if_fail (G_TYPE_CHECK_INSTANCE (instance));
SIGNAL_LOCK ();
emission = emission_find_innermost (instance);
if (emission)
{
node = LOOKUP_SIGNAL_NODE (emission->ihint.signal_id);
g_assert (node != NULL); /* paranoid */
/* we should probably do the same parameter checks as g_signal_emit() here.
*/
if (emission->chain_type != G_TYPE_NONE)
{
ClassClosure *cc = signal_find_class_closure (node, emission->chain_type);
g_assert (cc != NULL); /* closure currently in call stack */
n_params = node->n_params;
restore_type = cc->instance_type;
cc = signal_find_class_closure (node, g_type_parent (cc->instance_type));
if (cc && cc->instance_type != restore_type)
{
closure = cc->closure;
chain_type = cc->instance_type;
}
}
else
g_critical ("%s: signal id '%u' cannot be chained from current emission stage for instance '%p'", G_STRLOC, node->signal_id, instance);
}
else
g_critical ("%s: no signal is currently being emitted for instance '%p'", G_STRLOC, instance);
if (closure)
{
GValue *instance_and_params;
GType signal_return_type;
GValue *param_values;
va_list var_args;
guint i;
va_start (var_args, instance);
signal_return_type = node->return_type;
instance_and_params = g_newa0 (GValue, n_params + 1);
param_values = instance_and_params + 1;
for (i = 0; i < node->n_params; i++)
{
gchar *error;
GType ptype = node->param_types[i] & ~G_SIGNAL_TYPE_STATIC_SCOPE;
gboolean static_scope = node->param_types[i] & G_SIGNAL_TYPE_STATIC_SCOPE;
SIGNAL_UNLOCK ();
G_VALUE_COLLECT_INIT (param_values + i, ptype,
var_args,
static_scope ? G_VALUE_NOCOPY_CONTENTS : 0,
&error);
if (error)
{
g_critical ("%s: %s", G_STRLOC, error);
g_free (error);
/* we purposely leak the value here, it might not be
* in a correct state if an error condition occurred
*/
while (i--)
g_value_unset (param_values + i);
va_end (var_args);
return;
}
SIGNAL_LOCK ();
}
SIGNAL_UNLOCK ();
instance_and_params->g_type = 0;
g_value_init_from_instance (instance_and_params, instance);
SIGNAL_LOCK ();
emission->chain_type = chain_type;
SIGNAL_UNLOCK ();
if (signal_return_type == G_TYPE_NONE)
{
g_closure_invoke (closure,
NULL,
n_params + 1,
instance_and_params,
&emission->ihint);
}
else
{
GValue return_value = G_VALUE_INIT;
gchar *error = NULL;
GType rtype = signal_return_type & ~G_SIGNAL_TYPE_STATIC_SCOPE;
gboolean static_scope = signal_return_type & G_SIGNAL_TYPE_STATIC_SCOPE;
g_value_init (&return_value, rtype);
g_closure_invoke (closure,
&return_value,
n_params + 1,
instance_and_params,
&emission->ihint);
G_VALUE_LCOPY (&return_value,
var_args,
static_scope ? G_VALUE_NOCOPY_CONTENTS : 0,
&error);
if (!error)
{
g_value_unset (&return_value);
}
else
{
g_critical ("%s: %s", G_STRLOC, error);
g_free (error);
/* we purposely leak the value here, it might not be
* in a correct state if an error condition occurred
*/
}
}
for (i = 0; i < n_params; i++)
g_value_unset (param_values + i);
g_value_unset (instance_and_params);
va_end (var_args);
SIGNAL_LOCK ();
emission->chain_type = restore_type;
}
SIGNAL_UNLOCK ();
}
/**
* g_signal_get_invocation_hint:
* @instance: (type GObject.Object): the instance to query
*
* Returns the invocation hint of the innermost signal emission of instance.
*
* Returns: (transfer none) (nullable): the invocation hint of the innermost
* signal emission, or %NULL if not found.
*/
GSignalInvocationHint*
g_signal_get_invocation_hint (gpointer instance)
{
Emission *emission = NULL;
g_return_val_if_fail (G_TYPE_CHECK_INSTANCE (instance), NULL);
SIGNAL_LOCK ();
emission = emission_find_innermost (instance);
SIGNAL_UNLOCK ();
return emission ? &emission->ihint : NULL;
}
/**
* g_signal_connect_closure_by_id:
* @instance: (type GObject.Object): the instance to connect to.
* @signal_id: the id of the signal.
* @detail: the detail.
* @closure: (not nullable): the closure to connect.
* @after: whether the handler should be called before or after the
* default handler of the signal.
*
* Connects a closure to a signal for a particular object.
*
* If @closure is a floating reference (see g_closure_sink()), this function
* takes ownership of @closure.
*
* Returns: the handler ID (always greater than 0 for successful connections)
*/
gulong
g_signal_connect_closure_by_id (gpointer instance,
guint signal_id,
GQuark detail,
GClosure *closure,
gboolean after)
{
SignalNode *node;
gulong handler_seq_no = 0;
g_return_val_if_fail (G_TYPE_CHECK_INSTANCE (instance), 0);
g_return_val_if_fail (signal_id > 0, 0);
g_return_val_if_fail (closure != NULL, 0);
SIGNAL_LOCK ();
node = LOOKUP_SIGNAL_NODE (signal_id);
if (node)
{
if (detail && !(node->flags & G_SIGNAL_DETAILED))
g_critical ("%s: signal id '%u' does not support detail (%u)", G_STRLOC, signal_id, detail);
else if (!g_type_is_a (G_TYPE_FROM_INSTANCE (instance), node->itype))
g_critical ("%s: signal id '%u' is invalid for instance '%p'", G_STRLOC, signal_id, instance);
else
{
Handler *handler = handler_new (signal_id, instance, after);
if (G_TYPE_IS_OBJECT (node->itype))
_g_object_set_has_signal_handler ((GObject *) instance, signal_id);
handler_seq_no = handler->sequential_number;
handler->detail = detail;
handler->closure = g_closure_ref (closure);
g_closure_sink (closure);
add_invalid_closure_notify (handler, instance);
handler_insert (signal_id, instance, handler);
if (node->c_marshaller && G_CLOSURE_NEEDS_MARSHAL (closure))
{
g_closure_set_marshal (closure, node->c_marshaller);
if (node->va_marshaller)
_g_closure_set_va_marshal (closure, node->va_marshaller);
}
}
}
else
g_critical ("%s: signal id '%u' is invalid for instance '%p'", G_STRLOC, signal_id, instance);
SIGNAL_UNLOCK ();
return handler_seq_no;
}
/**
* g_signal_connect_closure:
* @instance: (type GObject.Object): the instance to connect to.
* @detailed_signal: a string of the form "signal-name::detail".
* @closure: (not nullable): the closure to connect.
* @after: whether the handler should be called before or after the
* default handler of the signal.
*
* Connects a closure to a signal for a particular object.
*
* If @closure is a floating reference (see g_closure_sink()), this function
* takes ownership of @closure.
*
* Returns: the handler ID (always greater than 0 for successful connections)
*/
gulong
g_signal_connect_closure (gpointer instance,
const gchar *detailed_signal,
GClosure *closure,
gboolean after)
{
guint signal_id;
gulong handler_seq_no = 0;
GQuark detail = 0;
GType itype;
g_return_val_if_fail (G_TYPE_CHECK_INSTANCE (instance), 0);
g_return_val_if_fail (detailed_signal != NULL, 0);
g_return_val_if_fail (closure != NULL, 0);
SIGNAL_LOCK ();
itype = G_TYPE_FROM_INSTANCE (instance);
signal_id = signal_parse_name (detailed_signal, itype, &detail, TRUE);
if (signal_id)
{
SignalNode *node = LOOKUP_SIGNAL_NODE (signal_id);
if (detail && !(node->flags & G_SIGNAL_DETAILED))
g_critical ("%s: signal '%s' does not support details", G_STRLOC, detailed_signal);
else if (!g_type_is_a (itype, node->itype))
g_critical ("%s: signal '%s' is invalid for instance '%p' of type '%s'",
G_STRLOC, detailed_signal, instance, g_type_name (itype));
else
{
Handler *handler = handler_new (signal_id, instance, after);
if (G_TYPE_IS_OBJECT (node->itype))
_g_object_set_has_signal_handler ((GObject *) instance, signal_id);
handler_seq_no = handler->sequential_number;
handler->detail = detail;
handler->closure = g_closure_ref (closure);
g_closure_sink (closure);
add_invalid_closure_notify (handler, instance);
handler_insert (signal_id, instance, handler);
if (node->c_marshaller && G_CLOSURE_NEEDS_MARSHAL (handler->closure))
{
g_closure_set_marshal (handler->closure, node->c_marshaller);
if (node->va_marshaller)
_g_closure_set_va_marshal (handler->closure, node->va_marshaller);
}
}
}
else
g_critical ("%s: signal '%s' is invalid for instance '%p' of type '%s'",
G_STRLOC, detailed_signal, instance, g_type_name (itype));
SIGNAL_UNLOCK ();
return handler_seq_no;
}
static void
node_check_deprecated (const SignalNode *node)
{
static const gchar * g_enable_diagnostic = NULL;
if (G_UNLIKELY (!g_enable_diagnostic))
{
g_enable_diagnostic = g_getenv ("G_ENABLE_DIAGNOSTIC");
if (!g_enable_diagnostic)
g_enable_diagnostic = "0";
}
if (g_enable_diagnostic[0] == '1')
{
if (node->flags & G_SIGNAL_DEPRECATED)
{
g_warning ("The signal %s::%s is deprecated and shouldn't be used "
"anymore. It will be removed in a future version.",
type_debug_name (node->itype), node->name);
}
}
}
/**
* g_signal_connect_data:
* @instance: (type GObject.Object): the instance to connect to.
* @detailed_signal: a string of the form "signal-name::detail".
* @c_handler: (not nullable): the #GCallback to connect.
* @data: (nullable) (closure c_handler): data to pass to @c_handler calls.
* @destroy_data: (nullable) (destroy data): a #GClosureNotify for @data.
* @connect_flags: a combination of #GConnectFlags.
*
* Connects a #GCallback function to a signal for a particular object. Similar
* to g_signal_connect(), but allows to provide a #GClosureNotify for the data
* which will be called when the signal handler is disconnected and no longer
* used. Specify @connect_flags if you need `..._after()` or
* `..._swapped()` variants of this function.
*
* Returns: the handler ID (always greater than 0 for successful connections)
*/
gulong
g_signal_connect_data (gpointer instance,
const gchar *detailed_signal,
GCallback c_handler,
gpointer data,
GClosureNotify destroy_data,
GConnectFlags connect_flags)
{
guint signal_id;
gulong handler_seq_no = 0;
GQuark detail = 0;
GType itype;
gboolean swapped, after;
g_return_val_if_fail (G_TYPE_CHECK_INSTANCE (instance), 0);
g_return_val_if_fail (detailed_signal != NULL, 0);
g_return_val_if_fail (c_handler != NULL, 0);
swapped = (connect_flags & G_CONNECT_SWAPPED) != FALSE;
after = (connect_flags & G_CONNECT_AFTER) != FALSE;
SIGNAL_LOCK ();
itype = G_TYPE_FROM_INSTANCE (instance);
signal_id = signal_parse_name (detailed_signal, itype, &detail, TRUE);
if (signal_id)
{
SignalNode *node = LOOKUP_SIGNAL_NODE (signal_id);
node_check_deprecated (node);
if (detail && !(node->flags & G_SIGNAL_DETAILED))
g_critical ("%s: signal '%s' does not support details", G_STRLOC, detailed_signal);
else if (!g_type_is_a (itype, node->itype))
g_critical ("%s: signal '%s' is invalid for instance '%p' of type '%s'",
G_STRLOC, detailed_signal, instance, g_type_name (itype));
else
{
Handler *handler = handler_new (signal_id, instance, after);
if (G_TYPE_IS_OBJECT (node->itype))
_g_object_set_has_signal_handler ((GObject *) instance, signal_id);
handler_seq_no = handler->sequential_number;
handler->detail = detail;
handler->closure = g_closure_ref ((swapped ? g_cclosure_new_swap : g_cclosure_new) (c_handler, data, destroy_data));
g_closure_sink (handler->closure);
handler_insert (signal_id, instance, handler);
if (node->c_marshaller && G_CLOSURE_NEEDS_MARSHAL (handler->closure))
{
g_closure_set_marshal (handler->closure, node->c_marshaller);
if (node->va_marshaller)
_g_closure_set_va_marshal (handler->closure, node->va_marshaller);
}
}
}
else
g_critical ("%s: signal '%s' is invalid for instance '%p' of type '%s'",
G_STRLOC, detailed_signal, instance, g_type_name (itype));
SIGNAL_UNLOCK ();
return handler_seq_no;
}
static void
signal_handler_block_unlocked (gpointer instance,
gulong handler_id);
/**
* g_signal_handler_block:
* @instance: (type GObject.Object): The instance to block the signal handler of.
* @handler_id: Handler id of the handler to be blocked.
*
* Blocks a handler of an instance so it will not be called during any
* signal emissions unless it is unblocked again. Thus "blocking" a
* signal handler means to temporarily deactivate it, a signal handler
* has to be unblocked exactly the same amount of times it has been
* blocked before to become active again.
*
* The @handler_id has to be a valid signal handler id, connected to a
* signal of @instance.
*/
void
g_signal_handler_block (gpointer instance,
gulong handler_id)
{
g_return_if_fail (G_TYPE_CHECK_INSTANCE (instance));
g_return_if_fail (handler_id > 0);
SIGNAL_LOCK ();
signal_handler_block_unlocked (instance, handler_id);
SIGNAL_UNLOCK ();
}
static void
signal_handler_block_unlocked (gpointer instance,
gulong handler_id)
{
Handler *handler;
handler = handler_lookup (instance, handler_id, NULL, NULL);
if (handler)
{
#ifndef G_DISABLE_CHECKS
if (handler->block_count >= HANDLER_MAX_BLOCK_COUNT - 1)
g_error (G_STRLOC ": handler block_count overflow, %s", REPORT_BUG);
#endif
handler->block_count += 1;
}
else
g_critical ("%s: instance '%p' has no handler with id '%lu'", G_STRLOC, instance, handler_id);
}
static void
signal_handler_unblock_unlocked (gpointer instance,
gulong handler_id);
/**
* g_signal_handler_unblock:
* @instance: (type GObject.Object): The instance to unblock the signal handler of.
* @handler_id: Handler id of the handler to be unblocked.
*
* Undoes the effect of a previous g_signal_handler_block() call. A
* blocked handler is skipped during signal emissions and will not be
* invoked, unblocking it (for exactly the amount of times it has been
* blocked before) reverts its "blocked" state, so the handler will be
* recognized by the signal system and is called upon future or
* currently ongoing signal emissions (since the order in which
* handlers are called during signal emissions is deterministic,
* whether the unblocked handler in question is called as part of a
* currently ongoing emission depends on how far that emission has
* proceeded yet).
*
* The @handler_id has to be a valid id of a signal handler that is
* connected to a signal of @instance and is currently blocked.
*/
void
g_signal_handler_unblock (gpointer instance,
gulong handler_id)
{
g_return_if_fail (G_TYPE_CHECK_INSTANCE (instance));
g_return_if_fail (handler_id > 0);
SIGNAL_LOCK ();
signal_handler_unblock_unlocked (instance, handler_id);
SIGNAL_UNLOCK ();
}
static void
signal_handler_unblock_unlocked (gpointer instance,
gulong handler_id)
{
Handler *handler;
handler = handler_lookup (instance, handler_id, NULL, NULL);
if (handler)
{
if (handler->block_count)
handler->block_count -= 1;
else
g_critical (G_STRLOC ": handler '%lu' of instance '%p' is not blocked", handler_id, instance);
}
else
g_critical ("%s: instance '%p' has no handler with id '%lu'", G_STRLOC, instance, handler_id);
}
static void
signal_handler_disconnect_unlocked (gpointer instance,
gulong handler_id);
/**
* g_signal_handler_disconnect:
* @instance: (type GObject.Object): The instance to remove the signal handler from.
* @handler_id: Handler id of the handler to be disconnected.
*
* Disconnects a handler from an instance so it will not be called during
* any future or currently ongoing emissions of the signal it has been
* connected to. The @handler_id becomes invalid and may be reused.
*
* The @handler_id has to be a valid signal handler id, connected to a
* signal of @instance.
*/
void
g_signal_handler_disconnect (gpointer instance,
gulong handler_id)
{
g_return_if_fail (G_TYPE_CHECK_INSTANCE (instance));
g_return_if_fail (handler_id > 0);
SIGNAL_LOCK ();
signal_handler_disconnect_unlocked (instance, handler_id);
SIGNAL_UNLOCK ();
}
static void
signal_handler_disconnect_unlocked (gpointer instance,
gulong handler_id)
{
Handler *handler;
handler = handler_lookup (instance, handler_id, 0, 0);
if (handler)
{
g_hash_table_remove (g_handlers, handler);
handler->sequential_number = 0;
handler->block_count = 1;
remove_invalid_closure_notify (handler, instance);
handler_unref_R (handler->signal_id, instance, handler);
}
else
g_critical ("%s: instance '%p' has no handler with id '%lu'", G_STRLOC, instance, handler_id);
}
/**
* g_signal_handler_is_connected:
* @instance: (type GObject.Object): The instance where a signal handler is sought.
* @handler_id: the handler ID.
*
* Returns whether @handler_id is the ID of a handler connected to @instance.
*
* Returns: whether @handler_id identifies a handler connected to @instance.
*/
gboolean
g_signal_handler_is_connected (gpointer instance,
gulong handler_id)
{
Handler *handler;
gboolean connected;
g_return_val_if_fail (G_TYPE_CHECK_INSTANCE (instance), FALSE);
SIGNAL_LOCK ();
handler = handler_lookup (instance, handler_id, NULL, NULL);
connected = handler != NULL;
SIGNAL_UNLOCK ();
return connected;
}
/**
* g_signal_handlers_destroy:
* @instance: (type GObject.Object): The instance whose signal handlers are destroyed
*
* Destroy all signal handlers of a type instance. This function is
* an implementation detail of the #GObject dispose implementation,
* and should not be used outside of the type system.
*/
void
g_signal_handlers_destroy (gpointer instance)
{
GBSearchArray *hlbsa;
g_return_if_fail (G_TYPE_CHECK_INSTANCE (instance));
SIGNAL_LOCK ();
hlbsa = g_hash_table_lookup (g_handler_list_bsa_ht, instance);
if (hlbsa)
{
guint i;
/* reentrancy caution, delete instance trace first */
g_hash_table_remove (g_handler_list_bsa_ht, instance);
for (i = 0; i < hlbsa->n_nodes; i++)
{
HandlerList *hlist = g_bsearch_array_get_nth (hlbsa, &g_signal_hlbsa_bconfig, i);
Handler *handler = hlist->handlers;
while (handler)
{
Handler *tmp = handler;
handler = tmp->next;
tmp->block_count = 1;
/* cruel unlink, this works because _all_ handlers vanish */
tmp->next = NULL;
tmp->prev = tmp;
if (tmp->sequential_number)
{
g_hash_table_remove (g_handlers, tmp);
remove_invalid_closure_notify (tmp, instance);
tmp->sequential_number = 0;
handler_unref_R (0, NULL, tmp);
}
}
}
g_bsearch_array_free (hlbsa, &g_signal_hlbsa_bconfig);
}
SIGNAL_UNLOCK ();
}
/**
* g_signal_handler_find:
* @instance: (type GObject.Object): The instance owning the signal handler to be found.
* @mask: Mask indicating which of @signal_id, @detail, @closure, @func
* and/or @data the handler has to match.
* @signal_id: Signal the handler has to be connected to.
* @detail: Signal detail the handler has to be connected to.
* @closure: (nullable): The closure the handler will invoke.
* @func: The C closure callback of the handler (useless for non-C closures).
* @data: (nullable) (closure closure): The closure data of the handler's closure.
*
* Finds the first signal handler that matches certain selection criteria.
* The criteria mask is passed as an OR-ed combination of #GSignalMatchType
* flags, and the criteria values are passed as arguments.
* The match @mask has to be non-0 for successful matches.
* If no handler was found, 0 is returned.
*
* Returns: A valid non-0 signal handler id for a successful match.
*/
gulong
g_signal_handler_find (gpointer instance,
GSignalMatchType mask,
guint signal_id,
GQuark detail,
GClosure *closure,
gpointer func,
gpointer data)
{
gulong handler_seq_no = 0;
g_return_val_if_fail (G_TYPE_CHECK_INSTANCE (instance), 0);
g_return_val_if_fail ((mask & ~G_SIGNAL_MATCH_MASK) == 0, 0);
if (mask & G_SIGNAL_MATCH_MASK)
{
HandlerMatch *mlist;
SIGNAL_LOCK ();
mlist = handlers_find (instance, mask, signal_id, detail, closure, func, data, TRUE);
if (mlist)
{
handler_seq_no = mlist->handler->sequential_number;
handler_match_free1_R (mlist, instance);
}
SIGNAL_UNLOCK ();
}
return handler_seq_no;
}
typedef void (*CallbackHandlerFunc) (gpointer instance, gulong handler_seq_no);
static guint
signal_handlers_foreach_matched_unlocked_R (gpointer instance,
GSignalMatchType mask,
guint signal_id,
GQuark detail,
GClosure *closure,
gpointer func,
gpointer data,
CallbackHandlerFunc callback)
{
HandlerMatch *mlist;
guint n_handlers = 0;
mlist = handlers_find (instance, mask, signal_id, detail, closure, func, data, FALSE);
while (mlist)
{
n_handlers++;
if (mlist->handler->sequential_number)
callback (instance, mlist->handler->sequential_number);
mlist = handler_match_free1_R (mlist, instance);
}
return n_handlers;
}
/**
* g_signal_handlers_block_matched:
* @instance: (type GObject.Object): The instance to block handlers from.
* @mask: Mask indicating which of @signal_id, @detail, @closure, @func
* and/or @data the handlers have to match.
* @signal_id: Signal the handlers have to be connected to.
* @detail: Signal detail the handlers have to be connected to.
* @closure: (nullable): The closure the handlers will invoke.
* @func: The C closure callback of the handlers (useless for non-C closures).
* @data: (nullable) (closure closure): The closure data of the handlers' closures.
*
* Blocks all handlers on an instance that match a certain selection criteria.
*
* The criteria mask is passed as a combination of #GSignalMatchType flags, and
* the criteria values are passed as arguments. A handler must match on all
* flags set in @mask to be blocked (i.e. the match is conjunctive).
*
* Passing at least one of the %G_SIGNAL_MATCH_ID, %G_SIGNAL_MATCH_CLOSURE,
* %G_SIGNAL_MATCH_FUNC
* or %G_SIGNAL_MATCH_DATA match flags is required for successful matches.
* If no handlers were found, 0 is returned, the number of blocked handlers
* otherwise.
*
* Support for %G_SIGNAL_MATCH_ID was added in GLib 2.78.
*
* Returns: The number of handlers that matched.
*/
guint
g_signal_handlers_block_matched (gpointer instance,
GSignalMatchType mask,
guint signal_id,
GQuark detail,
GClosure *closure,
gpointer func,
gpointer data)
{
guint n_handlers = 0;
g_return_val_if_fail (G_TYPE_CHECK_INSTANCE (instance), 0);
g_return_val_if_fail ((mask & ~G_SIGNAL_MATCH_MASK) == 0, 0);
if (mask & (G_SIGNAL_MATCH_ID | G_SIGNAL_MATCH_CLOSURE | G_SIGNAL_MATCH_FUNC | G_SIGNAL_MATCH_DATA))
{
SIGNAL_LOCK ();
n_handlers =
signal_handlers_foreach_matched_unlocked_R (instance, mask, signal_id, detail,
closure, func, data,
signal_handler_block_unlocked);
SIGNAL_UNLOCK ();
}
return n_handlers;
}
/**
* g_signal_handlers_unblock_matched:
* @instance: (type GObject.Object): The instance to unblock handlers from.
* @mask: Mask indicating which of @signal_id, @detail, @closure, @func
* and/or @data the handlers have to match.
* @signal_id: Signal the handlers have to be connected to.
* @detail: Signal detail the handlers have to be connected to.
* @closure: (nullable): The closure the handlers will invoke.
* @func: The C closure callback of the handlers (useless for non-C closures).
* @data: (nullable) (closure closure): The closure data of the handlers' closures.
*
* Unblocks all handlers on an instance that match a certain selection
* criteria.
*
* The criteria mask is passed as a combination of #GSignalMatchType flags, and
* the criteria values are passed as arguments. A handler must match on all
* flags set in @mask to be unblocked (i.e. the match is conjunctive).
*
* Passing at least one of the %G_SIGNAL_MATCH_ID, %G_SIGNAL_MATCH_CLOSURE,
* %G_SIGNAL_MATCH_FUNC
* or %G_SIGNAL_MATCH_DATA match flags is required for successful matches.
* If no handlers were found, 0 is returned, the number of unblocked handlers
* otherwise. The match criteria should not apply to any handlers that are
* not currently blocked.
*
* Support for %G_SIGNAL_MATCH_ID was added in GLib 2.78.
*
* Returns: The number of handlers that matched.
*/
guint
g_signal_handlers_unblock_matched (gpointer instance,
GSignalMatchType mask,
guint signal_id,
GQuark detail,
GClosure *closure,
gpointer func,
gpointer data)
{
guint n_handlers = 0;
g_return_val_if_fail (G_TYPE_CHECK_INSTANCE (instance), 0);
g_return_val_if_fail ((mask & ~G_SIGNAL_MATCH_MASK) == 0, 0);
if (mask & (G_SIGNAL_MATCH_ID | G_SIGNAL_MATCH_CLOSURE | G_SIGNAL_MATCH_FUNC | G_SIGNAL_MATCH_DATA))
{
SIGNAL_LOCK ();
n_handlers =
signal_handlers_foreach_matched_unlocked_R (instance, mask, signal_id, detail,
closure, func, data,
signal_handler_unblock_unlocked);
SIGNAL_UNLOCK ();
}
return n_handlers;
}
/**
* g_signal_handlers_disconnect_matched:
* @instance: (type GObject.Object): The instance to remove handlers from.
* @mask: Mask indicating which of @signal_id, @detail, @closure, @func
* and/or @data the handlers have to match.
* @signal_id: Signal the handlers have to be connected to.
* @detail: Signal detail the handlers have to be connected to.
* @closure: (nullable): The closure the handlers will invoke.
* @func: The C closure callback of the handlers (useless for non-C closures).
* @data: (nullable) (closure closure): The closure data of the handlers' closures.
*
* Disconnects all handlers on an instance that match a certain
* selection criteria.
*
* The criteria mask is passed as a combination of #GSignalMatchType flags, and
* the criteria values are passed as arguments. A handler must match on all
* flags set in @mask to be disconnected (i.e. the match is conjunctive).
*
* Passing at least one of the %G_SIGNAL_MATCH_ID, %G_SIGNAL_MATCH_CLOSURE,
* %G_SIGNAL_MATCH_FUNC or
* %G_SIGNAL_MATCH_DATA match flags is required for successful
* matches. If no handlers were found, 0 is returned, the number of
* disconnected handlers otherwise.
*
* Support for %G_SIGNAL_MATCH_ID was added in GLib 2.78.
*
* Returns: The number of handlers that matched.
*/
guint
g_signal_handlers_disconnect_matched (gpointer instance,
GSignalMatchType mask,
guint signal_id,
GQuark detail,
GClosure *closure,
gpointer func,
gpointer data)
{
guint n_handlers = 0;
g_return_val_if_fail (G_TYPE_CHECK_INSTANCE (instance), 0);
g_return_val_if_fail ((mask & ~G_SIGNAL_MATCH_MASK) == 0, 0);
if (mask & (G_SIGNAL_MATCH_ID | G_SIGNAL_MATCH_CLOSURE | G_SIGNAL_MATCH_FUNC | G_SIGNAL_MATCH_DATA))
{
SIGNAL_LOCK ();
n_handlers =
signal_handlers_foreach_matched_unlocked_R (instance, mask, signal_id, detail,
closure, func, data,
signal_handler_disconnect_unlocked);
SIGNAL_UNLOCK ();
}
return n_handlers;
}
/**
* g_signal_has_handler_pending:
* @instance: (type GObject.Object): the object whose signal handlers are sought.
* @signal_id: the signal id.
* @detail: the detail.
* @may_be_blocked: whether blocked handlers should count as match.
*
* Returns whether there are any handlers connected to @instance for the
* given signal id and detail.
*
* If @detail is 0 then it will only match handlers that were connected
* without detail. If @detail is non-zero then it will match handlers
* connected both without detail and with the given detail. This is
* consistent with how a signal emitted with @detail would be delivered
* to those handlers.
*
* Since 2.46 this also checks for a non-default class closure being
* installed, as this is basically always what you want.
*
* One example of when you might use this is when the arguments to the
* signal are difficult to compute. A class implementor may opt to not
* emit the signal if no one is attached anyway, thus saving the cost
* of building the arguments.
*
* Returns: %TRUE if a handler is connected to the signal, %FALSE
* otherwise.
*/
gboolean
g_signal_has_handler_pending (gpointer instance,
guint signal_id,
GQuark detail,
gboolean may_be_blocked)
{
HandlerMatch *mlist;
gboolean has_pending;
SignalNode *node;
g_return_val_if_fail (G_TYPE_CHECK_INSTANCE (instance), FALSE);
g_return_val_if_fail (signal_id > 0, FALSE);
SIGNAL_LOCK ();
node = LOOKUP_SIGNAL_NODE (signal_id);
if (detail)
{
if (!(node->flags & G_SIGNAL_DETAILED))
{
g_critical ("%s: signal id '%u' does not support detail (%u)", G_STRLOC, signal_id, detail);
SIGNAL_UNLOCK ();
return FALSE;
}
}
mlist = handlers_find (instance,
(G_SIGNAL_MATCH_ID | G_SIGNAL_MATCH_DETAIL | (may_be_blocked ? 0 : G_SIGNAL_MATCH_UNBLOCKED)),
signal_id, detail, NULL, NULL, NULL, TRUE);
if (mlist)
{
has_pending = TRUE;
handler_match_free1_R (mlist, instance);
}
else
{
ClassClosure *class_closure = signal_find_class_closure (node, G_TYPE_FROM_INSTANCE (instance));
if (class_closure != NULL && class_closure->instance_type != 0)
has_pending = TRUE;
else
has_pending = FALSE;
}
SIGNAL_UNLOCK ();
return has_pending;
}
/**
* g_signal_emitv:
* @instance_and_params: (array): argument list for the signal emission.
* The first element in the array is a #GValue for the instance the signal
* is being emitted on. The rest are any arguments to be passed to the signal.
* @signal_id: the signal id
* @detail: the detail
* @return_value: (inout) (optional): Location to
* store the return value of the signal emission. This must be provided if the
* specified signal returns a value, but may be ignored otherwise.
*
* Emits a signal. Signal emission is done synchronously.
* The method will only return control after all handlers are called or signal emission was stopped.
*
* Note that g_signal_emitv() doesn't change @return_value if no handlers are
* connected, in contrast to g_signal_emit() and g_signal_emit_valist().
*/
void
g_signal_emitv (const GValue *instance_and_params,
guint signal_id,
GQuark detail,
GValue *return_value)
{
gpointer instance;
SignalNode *node;
#ifdef G_ENABLE_DEBUG
const GValue *param_values;
guint i;
#endif
g_return_if_fail (instance_and_params != NULL);
instance = g_value_peek_pointer (instance_and_params);
g_return_if_fail (G_TYPE_CHECK_INSTANCE (instance));
g_return_if_fail (signal_id > 0);
#ifdef G_ENABLE_DEBUG
param_values = instance_and_params + 1;
#endif
SIGNAL_LOCK ();
node = LOOKUP_SIGNAL_NODE (signal_id);
if (!node || !g_type_is_a (G_TYPE_FROM_INSTANCE (instance), node->itype))
{
g_critical ("%s: signal id '%u' is invalid for instance '%p'", G_STRLOC, signal_id, instance);
SIGNAL_UNLOCK ();
return;
}
#ifdef G_ENABLE_DEBUG
if (detail && !(node->flags & G_SIGNAL_DETAILED))
{
g_critical ("%s: signal id '%u' does not support detail (%u)", G_STRLOC, signal_id, detail);
SIGNAL_UNLOCK ();
return;
}
for (i = 0; i < node->n_params; i++)
if (!G_TYPE_CHECK_VALUE_TYPE (param_values + i, node->param_types[i] & ~G_SIGNAL_TYPE_STATIC_SCOPE))
{
g_critical ("%s: value for '%s' parameter %u for signal \"%s\" is of type '%s'",
G_STRLOC,
type_debug_name (node->param_types[i]),
i,
node->name,
G_VALUE_TYPE_NAME (param_values + i));
SIGNAL_UNLOCK ();
return;
}
if (node->return_type != G_TYPE_NONE)
{
if (!return_value)
{
g_critical ("%s: return value '%s' for signal \"%s\" is (NULL)",
G_STRLOC,
type_debug_name (node->return_type),
node->name);
SIGNAL_UNLOCK ();
return;
}
else if (!node->accumulator && !G_TYPE_CHECK_VALUE_TYPE (return_value, node->return_type & ~G_SIGNAL_TYPE_STATIC_SCOPE))
{
g_critical ("%s: return value '%s' for signal \"%s\" is of type '%s'",
G_STRLOC,
type_debug_name (node->return_type),
node->name,
G_VALUE_TYPE_NAME (return_value));
SIGNAL_UNLOCK ();
return;
}
}
else
return_value = NULL;
#endif /* G_ENABLE_DEBUG */
/* optimize NOP emissions */
if (!node->single_va_closure_is_valid)
node_update_single_va_closure (node);
if (node->single_va_closure != NULL &&
(node->single_va_closure == SINGLE_VA_CLOSURE_EMPTY_MAGIC ||
_g_closure_is_void (node->single_va_closure, instance)))
{
HandlerList* hlist;
/* single_va_closure is only true for GObjects, so fast path if no handler ever connected to the signal */
if (_g_object_has_signal_handler ((GObject *)instance))
hlist = handler_list_lookup (node->signal_id, instance);
else
hlist = NULL;
if (hlist == NULL || hlist->handlers == NULL)
{
/* nothing to do to emit this signal */
SIGNAL_UNLOCK ();
/* g_printerr ("omitting emission of \"%s\"\n", node->name); */
return;
}
}
SIGNAL_UNLOCK ();
signal_emit_unlocked_R (node, detail, instance, return_value, instance_and_params);
}
static inline gboolean
accumulate (GSignalInvocationHint *ihint,
GValue *return_accu,
GValue *handler_return,
SignalAccumulator *accumulator)
{
gboolean continue_emission;
if (!accumulator)
return TRUE;
continue_emission = accumulator->func (ihint, return_accu, handler_return, accumulator->data);
g_value_reset (handler_return);
ihint->run_type &= ~G_SIGNAL_ACCUMULATOR_FIRST_RUN;
return continue_emission;
}
static gboolean
signal_emit_valist_unlocked (gpointer instance,
guint signal_id,
GQuark detail,
va_list var_args);
/**
* g_signal_emit_valist: (skip)
* @instance: (type GObject.TypeInstance): the instance the signal is being
* emitted on.
* @signal_id: the signal id
* @detail: the detail
* @var_args: a list of parameters to be passed to the signal, followed by a
* location for the return value. If the return type of the signal
* is %G_TYPE_NONE, the return value location can be omitted.
*
* Emits a signal. Signal emission is done synchronously.
* The method will only return control after all handlers are called or signal emission was stopped.
*
* Note that g_signal_emit_valist() resets the return value to the default
* if no handlers are connected, in contrast to g_signal_emitv().
*/
void
g_signal_emit_valist (gpointer instance,
guint signal_id,
GQuark detail,
va_list var_args)
{
SIGNAL_LOCK ();
if (signal_emit_valist_unlocked (instance, signal_id, detail, var_args))
SIGNAL_UNLOCK ();
}
/*
* signal_emit_valist_unlocked:
* @instance: The instance to emit from
* @signal_id: Signal id to emit
* @detail: Signal detail
* @var_args: Call arguments
*
* Returns: %TRUE if the signal mutex has been left locked
*/
static gboolean
signal_emit_valist_unlocked (gpointer instance,
guint signal_id,
GQuark detail,
va_list var_args)
{
GValue *instance_and_params;
GType signal_return_type;
GValue *param_values;
SignalNode *node;
guint i, n_params;
g_return_val_if_fail (G_TYPE_CHECK_INSTANCE (instance), TRUE);
g_return_val_if_fail (signal_id > 0, TRUE);
node = LOOKUP_SIGNAL_NODE (signal_id);
if (!node || !g_type_is_a (G_TYPE_FROM_INSTANCE (instance), node->itype))
{
g_critical ("%s: signal id '%u' is invalid for instance '%p'", G_STRLOC, signal_id, instance);
return TRUE;
}
#ifndef G_DISABLE_CHECKS
if (detail && !(node->flags & G_SIGNAL_DETAILED))
{
g_critical ("%s: signal id '%u' does not support detail (%u)", G_STRLOC, signal_id, detail);
return TRUE;
}
#endif /* !G_DISABLE_CHECKS */
if (!node->single_va_closure_is_valid)
node_update_single_va_closure (node);
if (node->single_va_closure != NULL)
{
HandlerList* hlist;
Handler *fastpath_handler = NULL;
Handler *l;
GClosure *closure = NULL;
gboolean fastpath = TRUE;
GSignalFlags run_type = G_SIGNAL_RUN_FIRST;
if (node->single_va_closure != SINGLE_VA_CLOSURE_EMPTY_MAGIC &&
!_g_closure_is_void (node->single_va_closure, instance))
{
if (_g_closure_supports_invoke_va (node->single_va_closure))
{
closure = node->single_va_closure;
if (node->single_va_closure_is_after)
run_type = G_SIGNAL_RUN_LAST;
else
run_type = G_SIGNAL_RUN_FIRST;
}
else
fastpath = FALSE;
}
/* single_va_closure is only true for GObjects, so fast path if no handler ever connected to the signal */
if (_g_object_has_signal_handler ((GObject *)instance))
hlist = handler_list_lookup (node->signal_id, instance);
else
hlist = NULL;
for (l = hlist ? hlist->handlers : NULL; fastpath && l != NULL; l = l->next)
{
if (!l->block_count &&
(!l->detail || l->detail == detail))
{
if (closure != NULL || !_g_closure_supports_invoke_va (l->closure))
{
fastpath = FALSE;
break;
}
else
{
fastpath_handler = l;
closure = l->closure;
if (l->after)
run_type = G_SIGNAL_RUN_LAST;
else
run_type = G_SIGNAL_RUN_FIRST;
}
}
}
if (fastpath && closure == NULL && node->return_type == G_TYPE_NONE)
return TRUE;
/* Don't allow no-recurse emission as we might have to restart, which means
we will run multiple handlers and thus must ref all arguments */
if (closure != NULL && (node->flags & (G_SIGNAL_NO_RECURSE)) != 0)
fastpath = FALSE;
if (fastpath)
{
SignalAccumulator *accumulator;
Emission emission;
GValue *return_accu, accu = G_VALUE_INIT;
GType instance_type = G_TYPE_FROM_INSTANCE (instance);
GValue emission_return = G_VALUE_INIT;
GType rtype = node->return_type & ~G_SIGNAL_TYPE_STATIC_SCOPE;
gboolean static_scope = node->return_type & G_SIGNAL_TYPE_STATIC_SCOPE;
signal_id = node->signal_id;
accumulator = node->accumulator;
if (rtype == G_TYPE_NONE)
return_accu = NULL;
else if (accumulator)
return_accu = &accu;
else
return_accu = &emission_return;
emission.instance = instance;
emission.ihint.signal_id = signal_id;
emission.ihint.detail = detail;
emission.ihint.run_type = run_type | G_SIGNAL_ACCUMULATOR_FIRST_RUN;
emission.state = EMISSION_RUN;
emission.chain_type = instance_type;
emission_push (&emission);
if (fastpath_handler)
handler_ref (fastpath_handler);
SIGNAL_UNLOCK ();
TRACE(GOBJECT_SIGNAL_EMIT(signal_id, detail, instance, instance_type));
if (rtype != G_TYPE_NONE)
g_value_init (&emission_return, rtype);
if (accumulator)
g_value_init (&accu, rtype);
if (closure != NULL)
{
/*
* Coverity doesn’t understand the paired ref/unref here and seems
* to ignore the ref, thus reports every call to g_signal_emit()
* as causing a double-free. That’s incorrect, but I can’t get a
* model file to work for avoiding the false positives, so instead
* comment out the ref/unref when doing static analysis.
*/
#ifndef __COVERITY__
g_object_ref (instance);
#endif
_g_closure_invoke_va (closure,
return_accu,
instance,
var_args,
node->n_params,
node->param_types);
accumulate (&emission.ihint, &emission_return, &accu, accumulator);
}
SIGNAL_LOCK ();
emission.chain_type = G_TYPE_NONE;
emission_pop (&emission);
if (fastpath_handler)
handler_unref_R (signal_id, instance, fastpath_handler);
SIGNAL_UNLOCK ();
if (accumulator)
g_value_unset (&accu);
if (rtype != G_TYPE_NONE)
{
gchar *error = NULL;
for (i = 0; i < node->n_params; i++)
{
GType ptype = node->param_types[i] & ~G_SIGNAL_TYPE_STATIC_SCOPE;
G_VALUE_COLLECT_SKIP (ptype, var_args);
}
G_VALUE_LCOPY (&emission_return,
var_args,
static_scope ? G_VALUE_NOCOPY_CONTENTS : 0,
&error);
if (!error)
g_value_unset (&emission_return);
else
{
g_critical ("%s: %s", G_STRLOC, error);
g_free (error);
/* we purposely leak the value here, it might not be
* in a correct state if an error condition occurred
*/
}
}
TRACE(GOBJECT_SIGNAL_EMIT_END(signal_id, detail, instance, instance_type));
/* See comment above paired ref above */
#ifndef __COVERITY__
if (closure != NULL)
g_object_unref (instance);
#endif
return FALSE;
}
}
SIGNAL_UNLOCK ();
n_params = node->n_params;
signal_return_type = node->return_type;
instance_and_params = g_newa0 (GValue, n_params + 1);
param_values = instance_and_params + 1;
for (i = 0; i < node->n_params; i++)
{
gchar *error;
GType ptype = node->param_types[i] & ~G_SIGNAL_TYPE_STATIC_SCOPE;
gboolean static_scope = node->param_types[i] & G_SIGNAL_TYPE_STATIC_SCOPE;
G_VALUE_COLLECT_INIT (param_values + i, ptype,
var_args,
static_scope ? G_VALUE_NOCOPY_CONTENTS : 0,
&error);
if (error)
{
g_critical ("%s: %s", G_STRLOC, error);
g_free (error);
/* we purposely leak the value here, it might not be
* in a correct state if an error condition occurred
*/
while (i--)
g_value_unset (param_values + i);
return FALSE;
}
}
instance_and_params->g_type = 0;
g_value_init_from_instance (instance_and_params, instance);
if (signal_return_type == G_TYPE_NONE)
signal_emit_unlocked_R (node, detail, instance, NULL, instance_and_params);
else
{
GValue return_value = G_VALUE_INIT;
gchar *error = NULL;
GType rtype = signal_return_type & ~G_SIGNAL_TYPE_STATIC_SCOPE;
gboolean static_scope = signal_return_type & G_SIGNAL_TYPE_STATIC_SCOPE;
g_value_init (&return_value, rtype);
signal_emit_unlocked_R (node, detail, instance, &return_value, instance_and_params);
G_VALUE_LCOPY (&return_value,
var_args,
static_scope ? G_VALUE_NOCOPY_CONTENTS : 0,
&error);
if (!error)
g_value_unset (&return_value);
else
{
g_critical ("%s: %s", G_STRLOC, error);
g_free (error);
/* we purposely leak the value here, it might not be
* in a correct state if an error condition occurred
*/
}
}
for (i = 0; i < n_params; i++)
g_value_unset (param_values + i);
g_value_unset (instance_and_params);
return FALSE;
}
/**
* g_signal_emit:
* @instance: (type GObject.Object): the instance the signal is being emitted on.
* @signal_id: the signal id
* @detail: the detail
* @...: parameters to be passed to the signal, followed by a
* location for the return value. If the return type of the signal
* is %G_TYPE_NONE, the return value location can be omitted.
*
* Emits a signal. Signal emission is done synchronously.
* The method will only return control after all handlers are called or signal emission was stopped.
*
* Note that g_signal_emit() resets the return value to the default
* if no handlers are connected, in contrast to g_signal_emitv().
*/
void
g_signal_emit (gpointer instance,
guint signal_id,
GQuark detail,
...)
{
va_list var_args;
va_start (var_args, detail);
g_signal_emit_valist (instance, signal_id, detail, var_args);
va_end (var_args);
}
/**
* g_signal_emit_by_name:
* @instance: (type GObject.Object): the instance the signal is being emitted on.
* @detailed_signal: a string of the form "signal-name::detail".
* @...: parameters to be passed to the signal, followed by a
* location for the return value. If the return type of the signal
* is %G_TYPE_NONE, the return value location can be omitted. The
* number of parameters to pass to this function is defined when creating the signal.
*
* Emits a signal. Signal emission is done synchronously.
* The method will only return control after all handlers are called or signal emission was stopped.
*
* Note that g_signal_emit_by_name() resets the return value to the default
* if no handlers are connected, in contrast to g_signal_emitv().
*/
void
g_signal_emit_by_name (gpointer instance,
const gchar *detailed_signal,
...)
{
GQuark detail = 0;
guint signal_id;
GType itype;
g_return_if_fail (G_TYPE_CHECK_INSTANCE (instance));
g_return_if_fail (detailed_signal != NULL);
itype = G_TYPE_FROM_INSTANCE (instance);
SIGNAL_LOCK ();
signal_id = signal_parse_name (detailed_signal, itype, &detail, TRUE);
if (signal_id)
{
va_list var_args;
va_start (var_args, detailed_signal);
if (signal_emit_valist_unlocked (instance, signal_id, detail, var_args))
SIGNAL_UNLOCK ();
va_end (var_args);
}
else
{
SIGNAL_UNLOCK ();
g_critical ("%s: signal name '%s' is invalid for instance '%p' of type '%s'",
G_STRLOC, detailed_signal, instance, g_type_name (itype));
}
}
static gboolean
signal_emit_unlocked_R (SignalNode *node,
GQuark detail,
gpointer instance,
GValue *emission_return,
const GValue *instance_and_params)
{
SignalAccumulator *accumulator;
Emission emission;
GClosure *class_closure;
HandlerList *hlist;
Handler *handler_list = NULL;
GValue *return_accu, accu = G_VALUE_INIT;
guint signal_id;
gulong max_sequential_handler_number;
gboolean return_value_altered = FALSE;
TRACE(GOBJECT_SIGNAL_EMIT(node->signal_id, detail, instance, G_TYPE_FROM_INSTANCE (instance)));
SIGNAL_LOCK ();
signal_id = node->signal_id;
if (node->flags & G_SIGNAL_NO_RECURSE)
{
Emission *emission_node = emission_find (signal_id, detail, instance);
if (emission_node)
{
emission_node->state = EMISSION_RESTART;
SIGNAL_UNLOCK ();
return return_value_altered;
}
}
accumulator = node->accumulator;
if (accumulator)
{
SIGNAL_UNLOCK ();
g_value_init (&accu, node->return_type & ~G_SIGNAL_TYPE_STATIC_SCOPE);
return_accu = &accu;
SIGNAL_LOCK ();
}
else
return_accu = emission_return;
emission.instance = instance;
emission.ihint.signal_id = node->signal_id;
emission.ihint.detail = detail;
emission.ihint.run_type = 0;
emission.state = 0;
emission.chain_type = G_TYPE_NONE;
emission_push (&emission);
class_closure = signal_lookup_closure (node, instance);
EMIT_RESTART:
if (handler_list)
handler_unref_R (signal_id, instance, handler_list);
max_sequential_handler_number = g_handler_sequential_number;
hlist = handler_list_lookup (signal_id, instance);
handler_list = hlist ? hlist->handlers : NULL;
if (handler_list)
handler_ref (handler_list);
emission.ihint.run_type = G_SIGNAL_RUN_FIRST | G_SIGNAL_ACCUMULATOR_FIRST_RUN;
if ((node->flags & G_SIGNAL_RUN_FIRST) && class_closure)
{
emission.state = EMISSION_RUN;
emission.chain_type = G_TYPE_FROM_INSTANCE (instance);
SIGNAL_UNLOCK ();
g_closure_invoke (class_closure,
return_accu,
node->n_params + 1,
instance_and_params,
&emission.ihint);
if (!accumulate (&emission.ihint, emission_return, &accu, accumulator) &&
emission.state == EMISSION_RUN)
emission.state = EMISSION_STOP;
SIGNAL_LOCK ();
emission.chain_type = G_TYPE_NONE;
return_value_altered = TRUE;
if (emission.state == EMISSION_STOP)
goto EMIT_CLEANUP;
else if (emission.state == EMISSION_RESTART)
goto EMIT_RESTART;
}
if (node->emission_hooks)
{
gboolean need_destroy, was_in_call, may_recurse = TRUE;
GHook *hook;
emission.state = EMISSION_HOOK;
hook = g_hook_first_valid (node->emission_hooks, may_recurse);
while (hook)
{
SignalHook *signal_hook = SIGNAL_HOOK (hook);
if (!signal_hook->detail || signal_hook->detail == detail)
{
GSignalEmissionHook hook_func = (GSignalEmissionHook) hook->func;
was_in_call = G_HOOK_IN_CALL (hook);
hook->flags |= G_HOOK_FLAG_IN_CALL;
SIGNAL_UNLOCK ();
need_destroy = !hook_func (&emission.ihint, node->n_params + 1, instance_and_params, hook->data);
SIGNAL_LOCK ();
if (!was_in_call)
hook->flags &= ~G_HOOK_FLAG_IN_CALL;
if (need_destroy)
g_hook_destroy_link (node->emission_hooks, hook);
}
hook = g_hook_next_valid (node->emission_hooks, hook, may_recurse);
}
if (emission.state == EMISSION_RESTART)
goto EMIT_RESTART;
}
if (handler_list)
{
Handler *handler = handler_list;
emission.state = EMISSION_RUN;
handler_ref (handler);
do
{
Handler *tmp;
if (handler->after)
{
handler_unref_R (signal_id, instance, handler_list);
handler_list = handler;
break;
}
else if (!handler->block_count && (!handler->detail || handler->detail == detail) &&
handler->sequential_number < max_sequential_handler_number)
{
SIGNAL_UNLOCK ();
g_closure_invoke (handler->closure,
return_accu,
node->n_params + 1,
instance_and_params,
&emission.ihint);
if (!accumulate (&emission.ihint, emission_return, &accu, accumulator) &&
emission.state == EMISSION_RUN)
emission.state = EMISSION_STOP;
SIGNAL_LOCK ();
return_value_altered = TRUE;
tmp = emission.state == EMISSION_RUN ? handler->next : NULL;
}
else
tmp = handler->next;
if (tmp)
handler_ref (tmp);
handler_unref_R (signal_id, instance, handler_list);
handler_list = handler;
handler = tmp;
}
while (handler);
if (emission.state == EMISSION_STOP)
goto EMIT_CLEANUP;
else if (emission.state == EMISSION_RESTART)
goto EMIT_RESTART;
}
emission.ihint.run_type &= ~G_SIGNAL_RUN_FIRST;
emission.ihint.run_type |= G_SIGNAL_RUN_LAST;
if ((node->flags & G_SIGNAL_RUN_LAST) && class_closure)
{
emission.state = EMISSION_RUN;
emission.chain_type = G_TYPE_FROM_INSTANCE (instance);
SIGNAL_UNLOCK ();
g_closure_invoke (class_closure,
return_accu,
node->n_params + 1,
instance_and_params,
&emission.ihint);
if (!accumulate (&emission.ihint, emission_return, &accu, accumulator) &&
emission.state == EMISSION_RUN)
emission.state = EMISSION_STOP;
SIGNAL_LOCK ();
emission.chain_type = G_TYPE_NONE;
return_value_altered = TRUE;
if (emission.state == EMISSION_STOP)
goto EMIT_CLEANUP;
else if (emission.state == EMISSION_RESTART)
goto EMIT_RESTART;
}
if (handler_list)
{
Handler *handler = handler_list;
emission.state = EMISSION_RUN;
handler_ref (handler);
do
{
Handler *tmp;
if (handler->after && !handler->block_count && (!handler->detail || handler->detail == detail) &&
handler->sequential_number < max_sequential_handler_number)
{
SIGNAL_UNLOCK ();
g_closure_invoke (handler->closure,
return_accu,
node->n_params + 1,
instance_and_params,
&emission.ihint);
if (!accumulate (&emission.ihint, emission_return, &accu, accumulator) &&
emission.state == EMISSION_RUN)
emission.state = EMISSION_STOP;
SIGNAL_LOCK ();
return_value_altered = TRUE;
tmp = emission.state == EMISSION_RUN ? handler->next : NULL;
}
else
tmp = handler->next;
if (tmp)
handler_ref (tmp);
handler_unref_R (signal_id, instance, handler);
handler = tmp;
}
while (handler);
if (emission.state == EMISSION_STOP)
goto EMIT_CLEANUP;
else if (emission.state == EMISSION_RESTART)
goto EMIT_RESTART;
}
EMIT_CLEANUP:
emission.ihint.run_type &= ~G_SIGNAL_RUN_LAST;
emission.ihint.run_type |= G_SIGNAL_RUN_CLEANUP;
if ((node->flags & G_SIGNAL_RUN_CLEANUP) && class_closure)
{
gboolean need_unset = FALSE;
emission.state = EMISSION_STOP;
emission.chain_type = G_TYPE_FROM_INSTANCE (instance);
SIGNAL_UNLOCK ();
if (node->return_type != G_TYPE_NONE && !accumulator)
{
g_value_init (&accu, node->return_type & ~G_SIGNAL_TYPE_STATIC_SCOPE);
need_unset = TRUE;
}
g_closure_invoke (class_closure,
node->return_type != G_TYPE_NONE ? &accu : NULL,
node->n_params + 1,
instance_and_params,
&emission.ihint);
if (!accumulate (&emission.ihint, emission_return, &accu, accumulator) &&
emission.state == EMISSION_RUN)
emission.state = EMISSION_STOP;
if (need_unset)
g_value_unset (&accu);
SIGNAL_LOCK ();
return_value_altered = TRUE;
emission.chain_type = G_TYPE_NONE;
if (emission.state == EMISSION_RESTART)
goto EMIT_RESTART;
}
if (handler_list)
handler_unref_R (signal_id, instance, handler_list);
emission_pop (&emission);
SIGNAL_UNLOCK ();
if (accumulator)
g_value_unset (&accu);
TRACE(GOBJECT_SIGNAL_EMIT_END(node->signal_id, detail, instance, G_TYPE_FROM_INSTANCE (instance)));
return return_value_altered;
}
static void
add_invalid_closure_notify (Handler *handler,
gpointer instance)
{
g_closure_add_invalidate_notifier (handler->closure, instance, invalid_closure_notify);
handler->has_invalid_closure_notify = 1;
}
static void
remove_invalid_closure_notify (Handler *handler,
gpointer instance)
{
if (handler->has_invalid_closure_notify)
{
g_closure_remove_invalidate_notifier (handler->closure, instance, invalid_closure_notify);
handler->has_invalid_closure_notify = 0;
}
}
static void
invalid_closure_notify (gpointer instance,
GClosure *closure)
{
Handler *handler;
guint signal_id;
SIGNAL_LOCK ();
handler = handler_lookup (instance, 0, closure, &signal_id);
/* See https://bugzilla.gnome.org/show_bug.cgi?id=730296 for discussion about this... */
g_assert (handler != NULL);
g_assert (handler->closure == closure);
g_hash_table_remove (g_handlers, handler);
handler->sequential_number = 0;
handler->block_count = 1;
handler_unref_R (signal_id, instance, handler);
SIGNAL_UNLOCK ();
}
static const gchar*
type_debug_name (GType type)
{
if (type)
{
const char *name = g_type_name (type & ~G_SIGNAL_TYPE_STATIC_SCOPE);
return name ? name : "";
}
else
return "";
}
/**
* g_signal_accumulator_true_handled:
* @ihint: standard #GSignalAccumulator parameter
* @return_accu: standard #GSignalAccumulator parameter
* @handler_return: standard #GSignalAccumulator parameter
* @dummy: standard #GSignalAccumulator parameter
*
* A predefined #GSignalAccumulator for signals that return a
* boolean values. The behavior that this accumulator gives is
* that a return of %TRUE stops the signal emission: no further
* callbacks will be invoked, while a return of %FALSE allows
* the emission to continue. The idea here is that a %TRUE return
* indicates that the callback handled the signal, and no further
* handling is needed.
*
* Since: 2.4
*
* Returns: standard #GSignalAccumulator result
*/
gboolean
g_signal_accumulator_true_handled (GSignalInvocationHint *ihint,
GValue *return_accu,
const GValue *handler_return,
gpointer dummy)
{
gboolean continue_emission;
gboolean signal_handled;
signal_handled = g_value_get_boolean (handler_return);
g_value_set_boolean (return_accu, signal_handled);
continue_emission = !signal_handled;
return continue_emission;
}
/**
* g_signal_accumulator_first_wins:
* @ihint: standard #GSignalAccumulator parameter
* @return_accu: standard #GSignalAccumulator parameter
* @handler_return: standard #GSignalAccumulator parameter
* @dummy: standard #GSignalAccumulator parameter
*
* A predefined #GSignalAccumulator for signals intended to be used as a
* hook for application code to provide a particular value. Usually
* only one such value is desired and multiple handlers for the same
* signal don't make much sense (except for the case of the default
* handler defined in the class structure, in which case you will
* usually want the signal connection to override the class handler).
*
* This accumulator will use the return value from the first signal
* handler that is run as the return value for the signal and not run
* any further handlers (ie: the first handler "wins").
*
* Returns: standard #GSignalAccumulator result
*
* Since: 2.28
**/
gboolean
g_signal_accumulator_first_wins (GSignalInvocationHint *ihint,
GValue *return_accu,
const GValue *handler_return,
gpointer dummy)
{
g_value_copy (handler_return, return_accu);
return FALSE;
}
/**
* g_clear_signal_handler:
* @handler_id_ptr: A pointer to a handler ID (of type #gulong) of the handler to be disconnected.
* @instance: (type GObject.Object): The instance to remove the signal handler from.
* This pointer may be %NULL or invalid, if the handler ID is zero.
*
* Disconnects a handler from @instance so it will not be called during
* any future or currently ongoing emissions of the signal it has been
* connected to. The @handler_id_ptr is then set to zero, which is never a valid handler ID value (see g_signal_connect()).
*
* If the handler ID is 0 then this function does nothing.
*
* There is also a macro version of this function so that the code
* will be inlined.
*
* Since: 2.62
*/
void
(g_clear_signal_handler) (gulong *handler_id_ptr,
gpointer instance)
{
g_return_if_fail (handler_id_ptr != NULL);
#ifndef g_clear_signal_handler
#error g_clear_signal_handler() macro is not defined
#endif
g_clear_signal_handler (handler_id_ptr, instance);
}