pub struct RawWaker {
data: *const (),
vtable: &'static RawWakerVTable,
}
Expand description
A RawWaker
allows the implementor of a task executor to create a Waker
or a LocalWaker
which provides customized wakeup behavior.
It consists of a data pointer and a virtual function pointer table (vtable)
that customizes the behavior of the RawWaker
.
RawWaker
s are unsafe to use.
Implementing the Wake
trait is a safe alternative that requires memory allocation.
Fields§
§data: *const ()
§vtable: &'static RawWakerVTable
Implementations§
source§impl RawWaker
impl RawWaker
1.36.0 (const: 1.36.0) · sourcepub const fn new(data: *const (), vtable: &'static RawWakerVTable) -> RawWaker
pub const fn new(data: *const (), vtable: &'static RawWakerVTable) -> RawWaker
Creates a new RawWaker
from the provided data
pointer and vtable
.
The data
pointer can be used to store arbitrary data as required
by the executor. This could be e.g. a type-erased pointer to an Arc
that is associated with the task.
The value of this pointer will get passed to all functions that are part
of the vtable
as the first parameter.
It is important to consider that the data
pointer must point to a
thread safe type such as an [Arc]<T: Send + Sync>
when used to construct a Waker
. This restriction is lifted when
constructing a LocalWaker
, which allows using types that do not implement
Send + Sync
like [Rc]<T>
.
The vtable
customizes the behavior of a Waker
which gets created
from a RawWaker
. For each operation on the Waker
, the associated
function in the vtable
of the underlying RawWaker
will be called.
sourcepub fn data(&self) -> *const ()
🔬This is a nightly-only experimental API. (waker_getters
#96992)
pub fn data(&self) -> *const ()
waker_getters
#96992)Gets the data
pointer used to create this RawWaker
.
sourcepub fn vtable(&self) -> &'static RawWakerVTable
🔬This is a nightly-only experimental API. (waker_getters
#96992)
pub fn vtable(&self) -> &'static RawWakerVTable
waker_getters
#96992)Gets the vtable
pointer used to create this RawWaker
.