1#[cfg(feature = "test-util")]
2use crate::runtime::scheduler;
3use crate::runtime::task::{self, Task, TaskHarnessScheduleHooks};
4use crate::runtime::Handle;
5
6/// `task::Schedule` implementation that does nothing (except some bookkeeping
7/// in test-util builds). This is unique to the blocking scheduler as tasks
8/// scheduled are not really futures but blocking operations.
9///
10/// We avoid storing the task by forgetting it in `bind` and re-materializing it
11/// in `release`.
12pub(crate) struct BlockingSchedule {
13 #[cfg(feature = "test-util")]
14 handle: Handle,
15 hooks: TaskHarnessScheduleHooks,
16}
17
18impl BlockingSchedule {
19 #[cfg_attr(not(feature = "test-util"), allow(unused_variables))]
20 pub(crate) fn new(handle: &Handle) -> Self {
21 #[cfg(feature = "test-util")]
22 {
23 match &handle.inner {
24 scheduler::Handle::CurrentThread(handle) => {
25 handle.driver.clock.inhibit_auto_advance();
26 }
27 #[cfg(feature = "rt-multi-thread")]
28 scheduler::Handle::MultiThread(_) => {}
29 #[cfg(all(tokio_unstable, feature = "rt-multi-thread"))]
30 scheduler::Handle::MultiThreadAlt(_) => {}
31 }
32 }
33 BlockingSchedule {
34 #[cfg(feature = "test-util")]
35 handle: handle.clone(),
36 hooks: TaskHarnessScheduleHooks {
37 task_terminate_callback: handle.inner.hooks().task_terminate_callback.clone(),
38 },
39 }
40 }
41}
42
43impl task::Schedule for BlockingSchedule {
44 fn release(&self, _task: &Task<Self>) -> Option<Task<Self>> {
45 #[cfg(feature = "test-util")]
46 {
47 match &self.handle.inner {
48 scheduler::Handle::CurrentThread(handle) => {
49 handle.driver.clock.allow_auto_advance();
50 handle.driver.unpark();
51 }
52 #[cfg(feature = "rt-multi-thread")]
53 scheduler::Handle::MultiThread(_) => {}
54 #[cfg(all(tokio_unstable, feature = "rt-multi-thread"))]
55 scheduler::Handle::MultiThreadAlt(_) => {}
56 }
57 }
58 None
59 }
60
61 fn schedule(&self, _task: task::Notified<Self>) {
62 unreachable!();
63 }
64
65 fn hooks(&self) -> TaskHarnessScheduleHooks {
66 TaskHarnessScheduleHooks {
67 task_terminate_callback: self.hooks.task_terminate_callback.clone(),
68 }
69 }
70}
71