GObject Reference Manual | ||||
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#include <glib-object.h> #define G_CLOSURE_NEEDS_MARSHAL (closure) #define G_CLOSURE_N_NOTIFIERS (cl) #define G_CCLOSURE_SWAP_DATA (cclosure) #define G_CALLBACK (f) void (*GCallback) (void); GClosure; #define G_TYPE_CLOSURE GCClosure; void (*GClosureMarshal) (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data); void (*GClosureNotify) (gpointer data, GClosure *closure); GClosure* g_cclosure_new (GCallback callback_func, gpointer user_data, GClosureNotify destroy_data); GClosure* g_cclosure_new_swap (GCallback callback_func, gpointer user_data, GClosureNotify destroy_data); GClosure* g_cclosure_new_object (GCallback callback_func, GObject *object); GClosure* g_cclosure_new_object_swap (GCallback callback_func, GObject *object); GClosure* g_closure_new_object (guint sizeof_closure, GObject *object); GClosure* g_closure_ref (GClosure *closure); void g_closure_sink (GClosure *closure); void g_closure_unref (GClosure *closure); void g_closure_invoke (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint); void g_closure_invalidate (GClosure *closure); void g_closure_add_finalize_notifier (GClosure *closure, gpointer notify_data, GClosureNotify notify_func); void g_closure_add_invalidate_notifier (GClosure *closure, gpointer notify_data, GClosureNotify notify_func); void g_closure_remove_finalize_notifier (GClosure *closure, gpointer notify_data, GClosureNotify notify_func); void g_closure_remove_invalidate_notifier (GClosure *closure, gpointer notify_data, GClosureNotify notify_func); GClosure* g_closure_new_simple (guint sizeof_closure, gpointer data); void g_closure_set_marshal (GClosure *closure, GClosureMarshal marshal); void g_closure_add_marshal_guards (GClosure *closure, gpointer pre_marshal_data, GClosureNotify pre_marshal_notify, gpointer post_marshal_data, GClosureNotify post_marshal_notify); void g_closure_set_meta_marshal (GClosure *closure, gpointer marshal_data, GClosureMarshal meta_marshal); void g_source_set_closure (GSource *source, GClosure *closure); #define G_TYPE_IO_CHANNEL #define G_TYPE_IO_CONDITION void g_cclosure_marshal_VOID__VOID (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data); void g_cclosure_marshal_VOID__BOOLEAN (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data); void g_cclosure_marshal_VOID__CHAR (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data); void g_cclosure_marshal_VOID__UCHAR (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data); void g_cclosure_marshal_VOID__INT (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data); void g_cclosure_marshal_VOID__UINT (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data); void g_cclosure_marshal_VOID__LONG (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data); void g_cclosure_marshal_VOID__ULONG (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data); void g_cclosure_marshal_VOID__ENUM (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data); void g_cclosure_marshal_VOID__FLAGS (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data); void g_cclosure_marshal_VOID__FLOAT (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data); void g_cclosure_marshal_VOID__DOUBLE (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data); void g_cclosure_marshal_VOID__STRING (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data); void g_cclosure_marshal_VOID__PARAM (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data); void g_cclosure_marshal_VOID__BOXED (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data); void g_cclosure_marshal_VOID__POINTER (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data); void g_cclosure_marshal_VOID__OBJECT (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data); void g_cclosure_marshal_STRING__OBJECT_POINTER (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data); void g_cclosure_marshal_VOID__UINT_POINTER (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data); void g_cclosure_marshal_BOOLEAN__FLAGS (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data); #define g_cclosure_marshal_BOOL__FLAGS
A GClosure represents a callback supplied by the programmer. It will generally comprise a function of some kind and a marshaller used to call it. It is the reponsibility of the marshaller to convert the arguments for the invocation from GValues into a suitable form, perform the callback on the converted arguments, and transform the return value back into a GValue.
In the case of C programs, a closure usually just holds a pointer to a function and maybe a data argument, and the marshaller converts between GValue and native C types. The GObject library provides the GCClosure type for this purpose. Bindings for other languages need marshallers which convert between GValues and suitable representations in the runtime of the language in order to use functions written in that languages as callbacks.
Within GObject, closures play an important role in the
implementation of signals. When a signal is registered, the
c_marshaller
argument to g_signal_new()
specifies the default C
marshaller for any closure which is connected to this
signal. GObject provides a number of C marshallers for this
purpose, see the g_cclosure_marshal_*() functions. Additional C
marshallers can be generated with the glib-genmarshal utility. Closures
can be explicitly connected to signals with
g_signal_connect_closure()
, but it usually more convenient to let
GObject create a closure automatically by using one of the
g_signal_connect_*() functions which take a callback function/user
data pair.
Using closures has a number of important advantages over a simple callback function/data pointer combination:
Closures allow the callee to get the types of the callback parameters, which means that language bindings don't have to write individual glue for each callback type.
The reference counting of GClosure makes it easy to handle reentrancy right; if a callback is removed while it is being invoked, the closure and it's parameters won't be freed until the invocation finishes.
g_closure_invalidate()
and invalidation notifiers allow callbacks to be
automatically removed when the objects they point to go away.
A GClosure represents a callback supplied by the programmer. It will generally comprise a function of some kind and a marshaller used to call it. It is the reponsibility of the marshaller to convert the arguments for the invocation from GValues into a suitable form, perform the callback on the converted arguments, and transform the return value back into a GValue.
In the case of C programs, a closure usually just holds a pointer to a function and maybe a data argument, and the marshaller converts between GValue and native C types. The GObject library provides the GCClosure type for this purpose. Bindings for other languages need marshallers which convert between GValues and suitable representations in the runtime of the language in order to use functions written in that languages as callbacks.
Within GObject, closures play an important role in the implementation of
signals. When a signal is registered, the c_marshaller
argument to
g_signal_new()
specifies the default C marshaller for any closure which is
connected to this signal. GObject provides a number of C marshallers
for this purpose, see the g_cclosure_marshal_*() functions. Additional
C marshallers can be generated with the glib-genmarshal utility.
Closures can be explicitly connected to signals with
g_signal_connect_closure()
, but it usually more convenient to let GObject
create a closure automatically by using one of the g_signal_connect_*()
functions which take a callback function/user data pair.
Using closures has a number of important advantages over a simple callback function/data pointer combination:
Closures allow the callee to get the types of the callback parameters, which means that language bindings don't have to write individual glue for each callback type.
The reference counting of GClosure makes it easy to handle reentrancy right; if a callback is removed while it is being invoked, the closure and it's parameters won't be freed until the invocation finishes.
g_closure_invalidate()
and invalidation notifiers allow callbacks to be
automatically removed when the objects they point to go away.
#define G_CLOSURE_NEEDS_MARSHAL(closure) (((GClosure*) (closure))->marshal == NULL)
Check if the closure still needs a marshaller. See g_closure_set_marshal()
.
Returns TRUE
if a GClosureMarshal marshaller has not yet been set on
closure
. See g_closure_set_marshal()
.
closure : |
a GClosure |
#define G_CLOSURE_N_NOTIFIERS(cl)
Get the total number of notifiers connected with the closure cl
.
The count includes the meta marshaller, the finalize and invalidate notifiers
and the marshal guards. Note that each guard counts as two notifiers.
See g_closure_set_meta_marshal()
, g_closure_add_finalize_notifier()
,
g_closure_add_invalidate_notifier()
and g_closure_add_marshal_guards()
.
Returns the total number of notifiers connected with the closure cl
.
The count includes the meta marshaller, the finalize and invalidate notifiers
and the marshal guards. Note that each guard counts as two notifiers.
See g_closure_set_meta_marshal()
, g_closure_add_finalize_notifier()
,
g_closure_add_invalidate_notifier()
and g_closure_add_marshal_guards()
.
cl : |
a GClosure |
#define G_CCLOSURE_SWAP_DATA(cclosure) (((GClosure*) (cclosure))->derivative_flag)
Checks whether the user data of the GCClosure should be passed as the
first parameter to the callback. See g_cclosure_new_swap()
.
Returns whether the user data of the GCClosure should be passed as the
first parameter to the callback. See g_cclosure_new_swap()
.
cclosure : |
a GCClosure |
#define G_CALLBACK(f) ((GCallback) (f))
Cast a function pointer to a GCallback.
Cast a function pointer to a GCallback.
f : |
a function pointer. |
void (*GCallback) (void);
The type used for callback functions in structure definitions and function
signatures. This doesn't mean that all callback functions must take no
parameters and return void. The required signature of a callback function
is determined by the context in which is used (e.g. the signal to which it
is connected). Use G_CALLBACK()
to cast the callback function to a GCallback.
The type used for callback functions in structure definitions and function
signatures. This doesn't mean that all callback functions must take no
parameters and return void. The required signature of a callback function
is determined by the context in which is used (e.g. the signal to which it
is connected). Use G_CALLBACK()
to cast the callback function to a GCallback.
typedef struct { volatile guint in_marshal : 1; volatile guint is_invalid : 1; } GClosure;
A GClosure represents a callback supplied by the programmer.
A GClosure represents a callback supplied by the programmer.
volatile guint in_marshal : 1; |
Indicates whether the closure is currently being invoked with
g_closure_invoke()
|
volatile guint is_invalid : 1; |
Indicates whether the closure has been invalidated by
g_closure_invalidate()
|
typedef struct { GClosure closure; gpointer callback; } GCClosure;
A GCClosure is a specialization of GClosure for C function callbacks.
A GCClosure is a specialization of GClosure for C function callbacks.
void (*GClosureMarshal) (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data);
The type used for marshaller functions.
The type used for marshaller functions.
closure : |
the GClosure to which the marshaller belongs |
return_value : |
a GValue to store the return value. May be NULL if the
callback of closure doesn't return a value.
|
n_param_values : |
the length of the param_values array
|
param_values : |
an array of GValues holding the arguments on
which to invoke the callback of closure
|
invocation_hint : |
the invocation hint given as the last argument
to g_closure_invoke()
|
marshal_data : |
additional data specified when registering the marshaller,
see g_closure_set_marshal() and g_closure_set_meta_marshal()
|
void (*GClosureNotify) (gpointer data, GClosure *closure);
The type used for the various notification callbacks which can be registered on closures.
The type used for the various notification callbacks which can be registered on closures.
data : |
data specified when registering the notification callback |
closure : |
the GClosure on which the notification is emitted |
GClosure* g_cclosure_new (GCallback callback_func, gpointer user_data, GClosureNotify destroy_data);
Creates a new closure which invokes callback_func
with user_data
as
the last parameter.
Creates a new closure which invokes callback_func
with user_data
as
the last parameter.
callback_func : |
the function to invoke |
user_data : |
user data to pass to callback_func
|
destroy_data : |
destroy notify to be called when user_data is no longer used
|
Returns : | a new GCClosure |
GClosure* g_cclosure_new_swap (GCallback callback_func, gpointer user_data, GClosureNotify destroy_data);
Creates a new closure which invokes callback_func
with user_data
as
the first parameter.
Creates a new closure which invokes callback_func
with user_data
as
the first parameter.
callback_func : |
the function to invoke |
user_data : |
user data to pass to callback_func
|
destroy_data : |
destroy notify to be called when user_data is no longer used
|
Returns : | a new GCClosure |
GClosure* g_cclosure_new_object (GCallback callback_func, GObject *object);
A variant of g_cclosure_new()
which uses object
as user_data
and
calls g_object_watch_closure()
on object
and the created
closure. This function is useful when you have a callback closely
associated with a GObject, and want the callback to no longer run
after the object is is freed.
A variant of g_cclosure_new()
which uses object
as user_data
and calls
g_object_watch_closure()
on object
and the created closure. This function
is useful when you have a callback closely associated with a GObject,
and want the callback to no longer run after the object is is freed.
GClosure* g_cclosure_new_object_swap (GCallback callback_func, GObject *object);
A variant of g_cclosure_new_swap()
which uses object
as user_data
and calls g_object_watch_closure()
on object
and the created
closure. This function is useful when you have a callback closely
associated with a GObject, and want the callback to no longer run
after the object is is freed.
A variant of g_cclosure_new_swap()
which uses object
as user_data
and calls
g_object_watch_closure()
on object
and the created closure. This function
is useful when you have a callback closely associated with a GObject,
and want the callback to no longer run after the object is is freed.
GClosure* g_closure_new_object (guint sizeof_closure, GObject *object);
A variant of g_closure_new_simple()
which stores object
in the
data
field of the closure and calls g_object_watch_closure()
on
object
and the created closure. This function is mainly useful
when implementing new types of closures.
A variant of g_closure_new_simple()
which stores object
in the data
field of the closure and calls g_object_watch_closure()
on object
and the
created closure. This function is mainly useful when implementing new types
of closures.
GClosure* g_closure_ref (GClosure *closure);
Increments the reference count on a closure to force it staying alive while the caller holds a pointer to it.
Increments the reference count on a closure to force it staying alive while the caller holds a pointer to it.
closure : |
GClosure to increment the reference count on |
Returns : | The closure passed in, for convenience
|
void g_closure_sink (GClosure *closure);
Takes over the initial ownership of a closure. Each closure is
initially created in a floating state, which
means that the initial reference count is not owned by any caller.
g_closure_sink()
checks to see if the object is still floating, and
if so, unsets the floating state and decreases the reference
count. If the closure is not floating, g_closure_sink()
does
nothing. The reason for the existance of the floating state is to
prevent cumbersome code sequences like:
closure = g_cclosure_new (cb_func, cb_data); g_source_set_closure (source, closure); g_closure_unref (closure); // XXX GObject doesn't really need this
Because g_source_set_closure()
(and similar functions) take ownership of the
initial reference count, if it is unowned, we instead can write:
g_source_set_closure (source, g_cclosure_new (cb_func, cb_data));
Generally, this function is used together with g_closure_ref()
. Ane example
of storing a closure for later notification looks like:
static GClosure *notify_closure = NULL; void foo_notify_set_closure (GClosure *closure) { if (notify_closure) g_closure_unref (notify_closure); notify_closure = closure; if (notify_closure) { g_closure_ref (notify_closure); g_closure_sink (notify_closure); } }
Because g_closure_sink()
may decrement the reference count of a closure
(if it hasn't been called on closure
yet) just like g_closure_unref()
,
g_closure_ref()
should be called prior to this function.
Takes over the initial ownership of a closure.
Each closure is initially created in a floating state,
which means that the initial reference count is not owned by any caller.
g_closure_sink()
checks to see if the object is still floating, and if so,
unsets the floating state and decreases the reference count. If the closure
is not floating, g_closure_sink()
does nothing. The reason for the existance
of the floating state is to prevent cumbersome code sequences like:
closure = g_cclosure_new (cb_func, cb_data); g_source_set_closure (source, closure); g_closure_unref (closure); /* XXX GObject doesn't really need this */
Because g_source_set_closure()
(and similar functions) take ownership of the
initial reference count, if it is unowned, we instead can write:
g_source_set_closure (source, g_cclosure_new (cb_func, cb_data));
Generally, this function is used together with g_closure_ref()
. Ane example
of storing a closure for later notification looks like:
static GClosure *notify_closure = NULL; void foo_notify_set_closure (GClosure *closure) { if (notify_closure) g_closure_unref (notify_closure); notify_closure = closure; if (notify_closure) { g_closure_ref (notify_closure); g_closure_sink (notify_closure); } }
Because g_closure_sink()
may decrement the reference count of a closure
(if it hasn't been called on closure
yet) just like g_closure_unref()
,
g_closure_ref()
should be called prior to this function.
closure : |
GClosure to decrement the initial reference count on, if it's still being held |
void g_closure_unref (GClosure *closure);
Decrements the reference count of a closure after it was previously incremented by the same caller. If no other callers are using the closure, then the closure will be destroyed and freed.
Decrements the reference count of a closure after it was previously incremented by the same caller. If no other callers are using the closure, then the closure will be destroyed and freed.
closure : |
GClosure to decrement the reference count on |
void g_closure_invoke (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint);
Invokes the closure, i.e. executes the callback represented by the closure
.
Invokes the closure, i.e. executes the callback represented by the closure
.
closure : |
a GClosure |
return_value : |
a GValue to store the return value. May be NULL if the
callback of closure doesn't return a value.
|
n_param_values : |
the length of the param_values array
|
param_values : |
an array of GValues holding the arguments on
which to invoke the callback of closure
|
invocation_hint : |
a context-dependent invocation hint |
void g_closure_invalidate (GClosure *closure);
Sets a flag on the closure to indicate that it's calling
environment has become invalid, and thus causes any future
invocations of g_closure_invoke()
on this closure
to be
ignored. Also, invalidation notifiers installed on the closure will
be called at this point. Note that unless you are holding a
reference to the closure yourself, the invalidation notifiers may
unref the closure and cause it to be destroyed, so if you need to
access the closure after calling g_closure_invalidate()
, make sure
that you've previously called g_closure_ref()
.
Note that g_closure_invalidate()
will also be called when the
reference count of a closure drops to zero (unless it has already
been invalidated before).
Sets a flag on the closure to indicate that it's calling environment has
become invalid, and thus causes any future invocations of g_closure_invoke()
on this closure
to be ignored. Also, invalidation notifiers installed on
the closure will be called at this point. Note that unless you are holding
a reference to the closure yourself, the invalidation notifiers may unref
the closure and cause it to be destroyed, so if you need to access the
closure after calling g_closure_invalidate()
, make sure that you've
previously called g_closure_ref()
.
Note that g_closure_invalidate()
will also be called when the reference count
of a closure drops to zero (unless it has already been invalidated before).
closure : |
GClosure to invalidate |
void g_closure_add_finalize_notifier (GClosure *closure, gpointer notify_data, GClosureNotify notify_func);
Registers a finalization notifier which will be called when the
reference count of closure
goes down to 0. Multiple finalization
notifiers on a single closure are invoked in unspecified order. If
a single call to g_closure_unref()
results in the closure being
both invalidated and finalized, then the invalidate notifiers will
be run before the finalize notifiers.
Registers a finalization notifier which will be called when the reference
count of closure
goes down to 0. Multiple finalization notifiers on a
single closure are invoked in unspecified order. If a single call to
g_closure_unref()
results in the closure being both invalidated and
finalized, then the invalidate notifiers will be run before the finalize
notifiers.
closure : |
a GClosure |
notify_data : |
data to pass to notify_func
|
notify_func : |
the callback function to register |
void g_closure_add_invalidate_notifier (GClosure *closure, gpointer notify_data, GClosureNotify notify_func);
Registers an invalidation notifier which will be called when the
closure
is invalidated with g_closure_invalidate()
. Invalidation
notifiers are invoked before finalization notifiers, in an
unspecified order.
Registers an invalidation notifier which will be called when the closure
is invalidated with g_closure_invalidate()
. Invalidation notifiers are
invoked before finalization notifiers, in an unspecified order.
closure : |
a GClosure |
notify_data : |
data to pass to notify_func
|
notify_func : |
the callback function to register |
void g_closure_remove_finalize_notifier (GClosure *closure, gpointer notify_data, GClosureNotify notify_func);
Removes a finalization notifier.
Notice that notifiers are automatically removed after they are run.
Removes a finalization notifier.
Notice that notifiers are automatically removed after they are run.
closure : |
a GClosure |
notify_data : |
data which was passed to g_closure_add_finalize_notifier()
when registering notify_func
|
notify_func : |
the callback function to remove |
void g_closure_remove_invalidate_notifier (GClosure *closure, gpointer notify_data, GClosureNotify notify_func);
Removes an invalidation notifier.
Notice that notifiers are automatically removed after they are run.
Removes an invalidation notifier.
Notice that notifiers are automatically removed after they are run.
closure : |
a GClosure |
notify_data : |
data which was passed to g_closure_add_invalidate_notifier()
when registering notify_func
|
notify_func : |
the callback function to remove |
GClosure* g_closure_new_simple (guint sizeof_closure, gpointer data);
Allocates a struct of the given size and initializes the initial part as a GClosure. This function is mainly useful when implementing new types of closures.
typedef struct _MyClosure MyClosure; struct _MyClosure { GClosure closure; // extra data goes here }; static void my_closure_finalize (gpointer notify_data, GClosure *closure) { MyClosure *my_closure = (MyClosure *)closure; // free extra data here } MyClosure *my_closure_new (gpointer data) { GClosure *closure; MyClosure *my_closure; closure = g_closure_new_simple (sizeof (MyClosure), data); my_closure = (MyClosure *) closure; // initialize extra data here g_closure_add_finalize_notifier (closure, notify_data, my_closure_finalize); return my_closure; }
Allocates a struct of the given size and initializes the initial part as a GClosure. This function is mainly useful when implementing new types of closures.
typedef struct _MyClosure MyClosure; struct _MyClosure { GClosure closure; /* extra data goes here */ }; static void my_closure_finalize (gpointer notify_data, GClosure *closure) { MyClosure *my_closure = (MyClosure *)closure; /* free extra data here */ } MyClosure *my_closure_new (gpointer data) { GClosure *closure; MyClosure *my_closure; closure = g_closure_new_simple (sizeof (MyClosure), data); my_closure = (MyClosure *) closure; / initialize extra data here */ g_closure_add_finalize_notifier (closure, notify_data, my_closure_finalize); return my_closure; }
void g_closure_set_marshal (GClosure *closure, GClosureMarshal marshal);
Sets the marshaller of closure
. The marshal_data
of marshal
provides a way for a meta marshaller to provide additional
information to the marshaller. (See g_closure_set_meta_marshal()
.) For
GObject's C predefined marshallers (the g_cclosure_marshal_*()
functions), what it provides is a callback function to use instead of
closure->callback
.
Sets the marshaller of closure
. The marshal_data
of marshal
provides a way for a meta marshaller to provide additional
information to the marshaller. (See g_closure_set_meta_marshal()
.) For
GObject's C predefined marshallers (the g_cclosure_marshal_*()
functions), what it provides is a callback function to use instead of
closure->callback
.
closure : |
a GClosure |
marshal : |
a GClosureMarshal function |
void g_closure_add_marshal_guards (GClosure *closure, gpointer pre_marshal_data, GClosureNotify pre_marshal_notify, gpointer post_marshal_data, GClosureNotify post_marshal_notify);
Adds a pair of notifiers which get invoked before and after the
closure callback, respectively. This is typically used to protect
the extra arguments for the duration of the callback. See
g_object_watch_closure()
for an example of marshal guards.
Adds a pair of notifiers which get invoked before and after the closure
callback, respectively. This is typically used to protect the extra arguments
for the duration of the callback. See g_object_watch_closure()
for an
example of marshal guards.
closure : |
a GClosure |
pre_marshal_data : |
data to pass to pre_marshal_notify
|
pre_marshal_notify : |
a function to call before the closure callback |
post_marshal_data : |
data to pass to post_marshal_notify
|
post_marshal_notify : |
a function to call after the closure callback |
void g_closure_set_meta_marshal (GClosure *closure, gpointer marshal_data, GClosureMarshal meta_marshal);
Sets the meta marshaller of closure
. A meta marshaller wraps
closure->marshal
and modifies the way it is called in some
fashion. The most common use of this facility is for C callbacks.
The same marshallers (generated by glib-genmarshal) are used
everywhere, but the way that we get the callback function
differs. In most cases we want to use closure->callback
, but in
other cases we want to use some different technique to retrieve the
callback function.
For example, class closures for signals (see
g_signal_type_cclosure_new()
) retrieve the callback function from a
fixed offset in the class structure. The meta marshaller retrieves
the right callback and passes it to the marshaller as the
marshal_data
argument.
Sets the meta marshaller of closure
.
A meta marshaller wraps closure->marshal
and modifies the way it is called
in some fashion. The most common use of this facility is for C callbacks.
The same marshallers (generated by
glib-genmarshal) are used everywhere,
but the way that we get the callback function differs. In most cases we want
to use closure->callback
, but in other cases we want to use some
different technique to retrieve the callback function.
For example, class closures for signals (see g_signal_type_cclosure_new()
)
retrieve the callback function from a fixed offset in the class structure.
The meta marshaller retrieves the right callback and passes it to the
marshaller as the marshal_data
argument.
closure : |
a GClosure |
marshal_data : |
context-dependent data to pass to meta_marshal
|
meta_marshal : |
a GClosureMarshal function |
void g_source_set_closure (GSource *source, GClosure *closure);
Set the callback for a source as a GClosure.
If the source is not one of the standard GLib types, the closure_callback
and closure_marshal
fields of the GSourceFuncs structure must have been
filled in with pointers to appropriate functions.
Set the callback for a source as a GClosure.
If the source is not one of the standard GLib types, the closure_callback
and closure_marshal
fields of the GSourceFuncs structure must have been
filled in with pointers to appropriate functions.
source : |
the source |
closure : |
a GClosure |
#define G_TYPE_IO_CHANNEL (g_io_channel_get_type ())
The GType for GIOChannel.
The GType for GIOChannel.
#define G_TYPE_IO_CONDITION (g_io_condition_get_type ())
The GType for GIOCondition.
The GType for GIOCondition.
void g_cclosure_marshal_VOID__VOID (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data);
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, gpointer user_data)
.
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, gpointer user_data)
.
closure : |
the GClosure to which the marshaller belongs |
return_value : |
ignored |
n_param_values : |
1 |
param_values : |
a GValue array holding only the instance |
invocation_hint : |
the invocation hint given as the last argument
to g_closure_invoke()
|
marshal_data : |
additional data specified when registering the marshaller |
void g_cclosure_marshal_VOID__BOOLEAN (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data);
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, gboolean arg1, gpointer user_data)
.
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, gboolean arg1, gpointer user_data)
.
closure : |
the GClosure to which the marshaller belongs |
return_value : |
ignored |
n_param_values : |
2 |
param_values : |
a GValue array holding the instance and the gboolean parameter |
invocation_hint : |
the invocation hint given as the last argument
to g_closure_invoke()
|
marshal_data : |
additional data specified when registering the marshaller |
void g_cclosure_marshal_VOID__CHAR (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data);
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, gchar arg1, gpointer user_data)
.
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, gchar arg1, gpointer user_data)
.
closure : |
the GClosure to which the marshaller belongs |
return_value : |
ignored |
n_param_values : |
2 |
param_values : |
a GValue array holding the instance and the gchar parameter |
invocation_hint : |
the invocation hint given as the last argument
to g_closure_invoke()
|
marshal_data : |
additional data specified when registering the marshaller |
void g_cclosure_marshal_VOID__UCHAR (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data);
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, guchar arg1, gpointer user_data)
.
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, guchar arg1, gpointer user_data)
.
closure : |
the GClosure to which the marshaller belongs |
return_value : |
ignored |
n_param_values : |
2 |
param_values : |
a GValue array holding the instance and the guchar parameter |
invocation_hint : |
the invocation hint given as the last argument
to g_closure_invoke()
|
marshal_data : |
additional data specified when registering the marshaller |
void g_cclosure_marshal_VOID__INT (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data);
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, gint arg1, gpointer user_data)
.
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, gint arg1, gpointer user_data)
.
closure : |
the GClosure to which the marshaller belongs |
return_value : |
ignored |
n_param_values : |
2 |
param_values : |
a GValue array holding the instance and the gint parameter |
invocation_hint : |
the invocation hint given as the last argument
to g_closure_invoke()
|
marshal_data : |
additional data specified when registering the marshaller |
void g_cclosure_marshal_VOID__UINT (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data);
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, guint arg1, gpointer user_data)
.
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, guint arg1, gpointer user_data)
.
closure : |
the GClosure to which the marshaller belongs |
return_value : |
ignored |
n_param_values : |
2 |
param_values : |
a GValue array holding the instance and the guint parameter |
invocation_hint : |
the invocation hint given as the last argument
to g_closure_invoke()
|
marshal_data : |
additional data specified when registering the marshaller |
void g_cclosure_marshal_VOID__LONG (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data);
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, glong arg1, gpointer user_data)
.
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, glong arg1, gpointer user_data)
.
closure : |
the GClosure to which the marshaller belongs |
return_value : |
ignored |
n_param_values : |
2 |
param_values : |
a GValue array holding the instance and the glong parameter |
invocation_hint : |
the invocation hint given as the last argument
to g_closure_invoke()
|
marshal_data : |
additional data specified when registering the marshaller |
void g_cclosure_marshal_VOID__ULONG (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data);
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, gulong arg1, gpointer user_data)
.
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, gulong arg1, gpointer user_data)
.
closure : |
the GClosure to which the marshaller belongs |
return_value : |
ignored |
n_param_values : |
2 |
param_values : |
a GValue array holding the instance and the gulong parameter |
invocation_hint : |
the invocation hint given as the last argument
to g_closure_invoke()
|
marshal_data : |
additional data specified when registering the marshaller |
void g_cclosure_marshal_VOID__ENUM (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data);
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, gint arg1, gpointer user_data)
where the gint parameter denotes an enumeration type..
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, gint arg1, gpointer user_data)
where the gint parameter denotes an enumeration type..
closure : |
the GClosure to which the marshaller belongs |
return_value : |
ignored |
n_param_values : |
2 |
param_values : |
a GValue array holding the instance and the enumeration parameter |
invocation_hint : |
the invocation hint given as the last argument
to g_closure_invoke()
|
marshal_data : |
additional data specified when registering the marshaller |
void g_cclosure_marshal_VOID__FLAGS (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data);
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, gint arg1, gpointer user_data)
where the gint parameter denotes a flags type.
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, gint arg1, gpointer user_data)
where the gint parameter denotes a flags type
denotes a flags type.
closure : |
the GClosure to which the marshaller belongs |
return_value : |
ignored |
n_param_values : |
2 |
param_values : |
a GValue array holding the instance and the flags parameter |
invocation_hint : |
the invocation hint given as the last argument
to g_closure_invoke()
|
marshal_data : |
additional data specified when registering the marshaller |
void g_cclosure_marshal_VOID__FLOAT (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data);
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, gfloat arg1, gpointer user_data)
.
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, gfloat arg1, gpointer user_data)
.
closure : |
the GClosure to which the marshaller belongs |
return_value : |
ignored |
n_param_values : |
2 |
param_values : |
a GValue array holding the instance and the gfloat parameter |
invocation_hint : |
the invocation hint given as the last argument
to g_closure_invoke()
|
marshal_data : |
additional data specified when registering the marshaller |
void g_cclosure_marshal_VOID__DOUBLE (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data);
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, gdouble arg1, gpointer user_data)
.
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, gdouble arg1, gpointer user_data)
.
closure : |
the GClosure to which the marshaller belongs |
return_value : |
ignored |
n_param_values : |
2 |
param_values : |
a GValue array holding the instance and the gdouble parameter |
invocation_hint : |
the invocation hint given as the last argument
to g_closure_invoke()
|
marshal_data : |
additional data specified when registering the marshaller |
void g_cclosure_marshal_VOID__STRING (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data);
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, const gchar *arg1, gpointer user_data)
.
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, const gchar *arg1, gpointer user_data)
.
closure : |
the GClosure to which the marshaller belongs |
return_value : |
ignored |
n_param_values : |
2 |
param_values : |
a GValue array holding the instance and the gchar* parameter |
invocation_hint : |
the invocation hint given as the last argument
to g_closure_invoke()
|
marshal_data : |
additional data specified when registering the marshaller |
void g_cclosure_marshal_VOID__PARAM (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data);
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, GParamSpec *arg1, gpointer user_data)
.
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, GParamSpec *arg1, gpointer user_data)
.
closure : |
the GClosure to which the marshaller belongs |
return_value : |
ignored |
n_param_values : |
2 |
param_values : |
a GValue array holding the instance and the GParamSpec* parameter |
invocation_hint : |
the invocation hint given as the last argument
to g_closure_invoke()
|
marshal_data : |
additional data specified when registering the marshaller |
void g_cclosure_marshal_VOID__BOXED (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data);
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, GBoxed *arg1, gpointer user_data)
.
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, GBoxed *arg1, gpointer user_data)
.
closure : |
the GClosure to which the marshaller belongs |
return_value : |
ignored |
n_param_values : |
2 |
param_values : |
a GValue array holding the instance and the GBoxed* parameter |
invocation_hint : |
the invocation hint given as the last argument
to g_closure_invoke()
|
marshal_data : |
additional data specified when registering the marshaller |
void g_cclosure_marshal_VOID__POINTER (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data);
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, gpointer arg1, gpointer user_data)
.
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, gpointer arg1, gpointer user_data)
.
closure : |
the GClosure to which the marshaller belongs |
return_value : |
ignored |
n_param_values : |
2 |
param_values : |
a GValue array holding the instance and the gpointer parameter |
invocation_hint : |
the invocation hint given as the last argument
to g_closure_invoke()
|
marshal_data : |
additional data specified when registering the marshaller |
void g_cclosure_marshal_VOID__OBJECT (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data);
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, GOBject *arg1, gpointer user_data)
.
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, GOBject *arg1, gpointer user_data)
.
closure : |
the GClosure to which the marshaller belongs |
return_value : |
ignored |
n_param_values : |
2 |
param_values : |
a GValue array holding the instance and the GObject* parameter |
invocation_hint : |
the invocation hint given as the last argument
to g_closure_invoke()
|
marshal_data : |
additional data specified when registering the marshaller |
void g_cclosure_marshal_STRING__OBJECT_POINTER (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data);
A marshaller for a GCClosure with a callback of type
gchar* (*callback) (gpointer instance, GObject *arg1, gpointer arg2, gpointer user_data)
.
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, GObject *arg1, gpointer arg2, gpointer user_data)
.
closure : |
the GClosure to which the marshaller belongs |
return_value : |
a GValue, which can store the returned string |
n_param_values : |
3 |
param_values : |
a GValue array holding instance, arg1 and arg2 |
invocation_hint : |
the invocation hint given as the last argument
to g_closure_invoke()
|
marshal_data : |
additional data specified when registering the marshaller |
void g_cclosure_marshal_VOID__UINT_POINTER (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data);
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, guint arg1, gpointer arg2, gpointer user_data)
.
A marshaller for a GCClosure with a callback of type
void (*callback) (gpointer instance, guint arg1, gpointer arg2, gpointer user_data)
.
closure : |
the GClosure to which the marshaller belongs |
return_value : |
ignored |
n_param_values : |
3 |
param_values : |
a GValue array holding instance, arg1 and arg2 |
invocation_hint : |
the invocation hint given as the last argument
to g_closure_invoke()
|
marshal_data : |
additional data specified when registering the marshaller |
void g_cclosure_marshal_BOOLEAN__FLAGS (GClosure *closure, GValue *return_value, guint n_param_values, const GValue *param_values, gpointer invocation_hint, gpointer marshal_data);
A marshaller for a GCClosure with a callback of type
gboolean (*callback) (gpointer instance, gint arg1, gpointer user_data)
where the gint parameter
denotes a flags type.
A marshaller for a GCClosure with a callback of type
gboolean (*callback) (gpointer instance, gint arg1, gpointer user_data)
where the gint parameter
denotes a flags type.
closure : |
the GClosure to which the marshaller belongs |
return_value : |
a GValue which can store the returned gboolean |
n_param_values : |
2 |
param_values : |
a GValue array holding instance and arg1 |
invocation_hint : |
the invocation hint given as the last argument
to g_closure_invoke()
|
marshal_data : |
additional data specified when registering the marshaller |
#define g_cclosure_marshal_BOOL__FLAGS
Another name for g_cclosure_marshal_BOOLEAN__FLAGS()
.
Another name for g_cclosure_marshal_BOOLEAN__FLAGS()
.