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
existence of the floating state is to prevent cumbersome code
sequences like:
|[<!-- language="C" -->
closure = g_cclosure_new (cb_func, cb_data);
g_source_set_closure (source, closure);
g_closure_unref (closure); // 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:
|[<!-- language="C" -->
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:
|[<!-- language="C" -->
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 existence of the floating state is to prevent cumbersome code sequences like: |[<!-- language="C" --> closure = g_cclosure_new (cb_func, cb_data); g_source_set_closure (source, closure); g_closure_unref (closure); // 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: |[<!-- language="C" --> 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: |[<!-- language="C" --> 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.