1 // Copyright (c) 2023 Huawei Device Co., Ltd.
2 // Licensed under the Apache License, Version 2.0 (the "License");
3 // you may not use this file except in compliance with the License.
4 // You may obtain a copy of the License at
5 //
6 //     http://www.apache.org/licenses/LICENSE-2.0
7 //
8 // Unless required by applicable law or agreed to in writing, software
9 // distributed under the License is distributed on an "AS IS" BASIS,
10 // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
11 // See the License for the specific language governing permissions and
12 // limitations under the License.
13 
14 use std::io;
15 
16 use crate::sys::WakerInner;
17 use crate::{Poll, Token};
18 
19 /// Waker allows cross-thread waking of Poll.
20 #[derive(Debug)]
21 pub struct Waker {
22     inner: WakerInner,
23 }
24 
25 impl Waker {
26     /// Creates a new Waker
new(poll: &Poll, token: Token) -> io::Result<Self>27     pub fn new(poll: &Poll, token: Token) -> io::Result<Self> {
28         WakerInner::new(poll.selector(), token).map(|inner| Waker { inner })
29     }
30     /// Wakes up the [`Poll`] associated with this `Waker`
wake(&self) -> io::Result<()>31     pub fn wake(&self) -> io::Result<()> {
32         self.inner.wake()
33     }
34 }
35 
36 #[cfg(test)]
37 mod test {
38     /// UT cases for debug info of waker
39     ///
40     /// # Brief
41     /// 1. Create a Waker
42     /// 2. Check its fmt debug info
43     #[test]
44     #[cfg(target_os = "linux")]
ut_waker_debug_info()45     fn ut_waker_debug_info() {
46         use crate::{Poll, Token, Waker};
47 
48         let poll = Poll::new().unwrap();
49         let waker = Waker::new(&poll, Token::from_usize(0)).unwrap();
50         let fmt = format!("{:?}", waker);
51         assert!(fmt.contains("fd:"));
52         assert!(fmt.contains("read:"));
53         assert!(fmt.contains("write:"));
54     }
55 }
56