risingwave_common/util/
runtime.rs

1// Copyright 2025 RisingWave Labs
2//
3// Licensed under the Apache License, Version 2.0 (the "License");
4// you may not use this file except in compliance with the License.
5// You may obtain a copy of the License at
6//
7//     http://www.apache.org/licenses/LICENSE-2.0
8//
9// Unless required by applicable law or agreed to in writing, software
10// distributed under the License is distributed on an "AS IS" BASIS,
11// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
12// See the License for the specific language governing permissions and
13// limitations under the License.
14
15use std::mem::ManuallyDrop;
16use std::ops::{Deref, DerefMut};
17
18use tokio::runtime::Runtime;
19
20/// A wrapper around [`Runtime`] that shuts down the runtime in the background when dropped.
21///
22/// This is necessary because directly dropping a nested runtime is not allowed in a parent runtime.
23pub struct BackgroundShutdownRuntime(ManuallyDrop<Runtime>);
24
25impl Drop for BackgroundShutdownRuntime {
26    fn drop(&mut self) {
27        // Safety: The runtime is only dropped once here.
28        let runtime = unsafe { ManuallyDrop::take(&mut self.0) };
29
30        #[cfg(madsim)]
31        drop(runtime);
32        #[cfg(not(madsim))]
33        runtime.shutdown_background();
34    }
35}
36
37impl Deref for BackgroundShutdownRuntime {
38    type Target = Runtime;
39
40    fn deref(&self) -> &Self::Target {
41        &self.0
42    }
43}
44
45impl DerefMut for BackgroundShutdownRuntime {
46    fn deref_mut(&mut self) -> &mut Self::Target {
47        &mut self.0
48    }
49}
50
51impl From<Runtime> for BackgroundShutdownRuntime {
52    fn from(runtime: Runtime) -> Self {
53        Self(ManuallyDrop::new(runtime))
54    }
55}
risingwave_common/util/runtime.rs

risingwave_common/util/
runtime.rs
