/*
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_invoke (GClosure *closure,
GValue /*out*/ *return_value,
guint n_param_values,
const GValue *param_values,
gpointer invocation_hint)
{
/*
设置状态防止重入
*/
closure->ref_count += 1;
closure->in_marshal = TRUE;
// 得到marshal的指针
if (closure->meta_marshal)
{
marshal_data = closure->notifiers[0].data;
marshal = (GClosureMarshal) closure->notifiers[0].notify;
}
else
{
marshal_data = NULL;
marshal = closure->marshal;
}
/*
分别调用
pre-notifer
marshal
post-notifier
*/
closure_invoke_notifiers (closure, PRE_NOTIFY);
marshal (closure,
return_value,
n_param_values, param_values,
invocation_hint,
marshal_data);
closure_invoke_notifiers (closure, POST_NOTIFY);
// 恢复重入状态
closure->in_marshal = in_marshal;
g_closure_unref (closure);
}
/**
* g_closure_invoke:
* @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: (array length=n_param_values): an array of
* #GValue<!-- -->s holding the arguments on which to
* invoke the callback of @closure
* @invocation_hint: a context-dependent invocation hint
*
* Invokes the closure, i.e. executes the callback represented by the @closure.
*/
void
g_closure_invoke (GClosure *closure,
GValue /*out*/ *return_value,
guint n_param_values,
const GValue *param_values,
gpointer invocation_hint)
{
g_return_if_fail (closure != NULL);
g_closure_ref (closure); /* preserve floating flag */
if (!closure->is_invalid)
{
GClosureMarshal marshal;
gpointer marshal_data;
gboolean in_marshal = closure->in_marshal;
g_return_if_fail (closure->marshal || closure->meta_marshal);
SET (closure, in_marshal, TRUE);
if (closure->meta_marshal)
{
marshal_data = closure->notifiers[0].data;
marshal = (GClosureMarshal) closure->notifiers[0].notify;
}
else
{
marshal_data = NULL;
marshal = closure->marshal;
}
if (!in_marshal)
closure_invoke_notifiers (closure, PRE_NOTIFY);
marshal (closure,
return_value,
n_param_values, param_values,
invocation_hint,
marshal_data);
if (!in_marshal)
closure_invoke_notifiers (closure, POST_NOTIFY);
SET (closure, in_marshal, in_marshal);
}
g_closure_unref (closure);
}
void
g_closure_invalidate (GClosure *closure)
{
g_return_if_fail (closure != NULL);
if (!closure->is_invalid)
{
closure->ref_count += 1; /* preserve floating flag */
closure->is_invalid = TRUE;
closure_invoke_notifiers (closure, INOTIFY);
g_closure_unref (closure);
}
}
/**
* g_closure_invalidate:
* @closure: GClosure to invalidate
*
* Sets a flag on the closure to indicate that its calling
* environment has become invalid, and thus causes any future
* invocations of g_closure_invoke() on this @closure to be
* ignored. Also, invalidation notifiers installed on the closure will
* be called at this point. Note that unless you are holding a
* reference to the closure yourself, the invalidation notifiers may
* unref the closure and cause it to be destroyed, so if you need to
* access the closure after calling g_closure_invalidate(), make sure
* that you've previously called g_closure_ref().
*
* Note that g_closure_invalidate() will also be called when the
* reference count of a closure drops to zero (unless it has already
* been invalidated before).
*/
void
g_closure_invalidate (GClosure *closure)
{
g_return_if_fail (closure != NULL);
if (!closure->is_invalid)
{
gboolean was_invalid;
g_closure_ref (closure); /* preserve floating flag */
SWAP (closure, is_invalid, TRUE, &was_invalid);
/* invalidate only once */
if (!was_invalid)
closure_invoke_notifiers (closure, INOTIFY);
g_closure_unref (closure);
}
}
void
g_closure_unref (GClosure *closure)
{
g_return_if_fail (closure != NULL);
g_return_if_fail (closure->ref_count > 0);
if (closure->ref_count == 1) /* last unref, invalidate first */
g_closure_invalidate (closure);
closure->ref_count -= 1;
if (closure->ref_count == 0)
{
closure_invoke_notifiers (closure, FNOTIFY);
g_free (closure->notifiers);
g_free (closure);
}
}
/**
* g_closure_unref:
* @closure: #GClosure to decrement the reference count on
*
* Decrements the reference count of a closure after it was previously
* incremented by the same caller. If no other callers are using the
* closure, then the closure will be destroyed and freed.
*/
void
g_closure_unref (GClosure *closure)
{
guint new_ref_count;
g_return_if_fail (closure != NULL);
g_return_if_fail (closure->ref_count > 0);
if (closure->ref_count == 1) /* last unref, invalidate first */
g_closure_invalidate (closure);
DEC_ASSIGN (closure, ref_count, &new_ref_count);
if (new_ref_count == 0)
{
closure_invoke_notifiers (closure, FNOTIFY);
g_free (closure->notifiers);
g_free (closure);
}
}
