-
Notifications
You must be signed in to change notification settings - Fork 150
Commit
This commit does not belong to any branch on this repository, and may belong to a fork outside of the repository.
split out select functions into their own module (#48035)
- Loading branch information
Showing
10 changed files
with
208 additions
and
186 deletions.
There are no files selected for viewing
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This file contains bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
| Original file line number | Diff line number | Diff line change |
|---|---|---|
| @@ -0,0 +1,190 @@ | ||
| /* | ||
| * Copyright (C) 2020-2023 Fanout, Inc. | ||
| * Copyright (C) 2024 Fastly, Inc. | ||
| * | ||
| * Licensed under the Apache License, Version 2.0 (the "License"); | ||
| * you may not use this file except in compliance with the License. | ||
| * You may obtain a copy of the License at | ||
| * | ||
| * http://www.apache.org/licenses/LICENSE-2.0 | ||
| * | ||
| * Unless required by applicable law or agreed to in writing, software | ||
| * distributed under the License is distributed on an "AS IS" BASIS, | ||
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. | ||
| * See the License for the specific language governing permissions and | ||
| * limitations under the License. | ||
| */ | ||
|
|
||
| use crate::core::shuffle::shuffle; | ||
| use paste::paste; | ||
| use std::future::Future; | ||
| use std::pin::Pin; | ||
| use std::task::{Context, Poll}; | ||
|
|
||
| fn range_unordered(dest: &mut [usize]) -> &[usize] { | ||
| for (index, v) in dest.iter_mut().enumerate() { | ||
| *v = index; | ||
| } | ||
|
|
||
| shuffle(dest); | ||
|
|
||
| dest | ||
| } | ||
|
|
||
| fn map_poll<F, W, V>(cx: &mut Context, fut: &mut F, wrap_func: W) -> Poll<V> | ||
| where | ||
| F: Future + Unpin, | ||
| W: FnOnce(F::Output) -> V, | ||
| { | ||
| match Pin::new(fut).poll(cx) { | ||
| Poll::Ready(v) => Poll::Ready(wrap_func(v)), | ||
| Poll::Pending => Poll::Pending, | ||
| } | ||
| } | ||
|
|
||
| macro_rules! declare_select { | ||
| ($count: literal, ( $($num:literal),* )) => { | ||
| paste! { | ||
| pub enum [<Select $count>]<$([<O $num>], )*> { | ||
| $( | ||
| [<R $num>]([<O $num>]), | ||
| )* | ||
| } | ||
|
|
||
| pub struct [<Select $count Future>]<$([<F $num>], )*> { | ||
| $( | ||
| [<f $num>]: [<F $num>], | ||
| )* | ||
| } | ||
|
|
||
| impl<$([<F $num>], )*> Future for [<Select $count Future>]<$([<F $num>], )*> | ||
| where | ||
| $( | ||
| [<F $num>]: Future + Unpin, | ||
| )* | ||
| { | ||
| type Output = [<Select $count>]<$([<F $num>]::Output, )*>; | ||
|
|
||
| fn poll(mut self: Pin<&mut Self>, cx: &mut Context) -> Poll<Self::Output> { | ||
| let mut indexes = [0; $count]; | ||
|
|
||
| for i in range_unordered(&mut indexes) { | ||
| let s = &mut *self; | ||
|
|
||
| let p = match i + 1 { | ||
| $( | ||
| $num => map_poll(cx, &mut s.[<f $num>], |v| [<Select $count>]::[<R $num>](v)), | ||
| )* | ||
| _ => unreachable!(), | ||
| }; | ||
|
|
||
| if p.is_ready() { | ||
| return p; | ||
| } | ||
| } | ||
|
|
||
| Poll::Pending | ||
| } | ||
| } | ||
|
|
||
| #[allow(clippy::too_many_arguments)] | ||
| pub fn [<select_ $count>]<$([<F $num>], )*>( | ||
| $( | ||
| [<f $num>]: [<F $num>], | ||
| )* | ||
| ) -> [<Select $count Future>]<$([<F $num>], )*> | ||
| where | ||
| $( | ||
| [<F $num>]: Future + Unpin, | ||
| )* | ||
| { | ||
| [<Select $count Future>] { | ||
| $( | ||
| [<f $num>], | ||
| )* | ||
| } | ||
| } | ||
| } | ||
| } | ||
| } | ||
|
|
||
| declare_select!(2, (1, 2)); | ||
| declare_select!(3, (1, 2, 3)); | ||
| declare_select!(4, (1, 2, 3, 4)); | ||
| declare_select!(5, (1, 2, 3, 4, 5)); | ||
| declare_select!(6, (1, 2, 3, 4, 5, 6)); | ||
| declare_select!(8, (1, 2, 3, 4, 5, 6, 7, 8)); | ||
| declare_select!(9, (1, 2, 3, 4, 5, 6, 7, 8, 9)); | ||
| declare_select!(10, (1, 2, 3, 4, 5, 6, 7, 8, 9, 10)); | ||
|
|
||
| pub struct SelectSliceFuture<'a, F> { | ||
| futures: &'a mut [F], | ||
| scratch: &'a mut Vec<usize>, | ||
| } | ||
|
|
||
| impl<F, O> Future for SelectSliceFuture<'_, F> | ||
| where | ||
| F: Future<Output = O> + Unpin, | ||
| { | ||
| type Output = (usize, F::Output); | ||
|
|
||
| fn poll(mut self: Pin<&mut Self>, cx: &mut Context) -> Poll<Self::Output> { | ||
| let s = &mut *self; | ||
|
|
||
| let indexes = &mut s.scratch; | ||
| indexes.resize(s.futures.len(), 0); | ||
|
|
||
| for i in range_unordered(&mut indexes[..s.futures.len()]) { | ||
| if let Poll::Ready(v) = Pin::new(&mut s.futures[*i]).poll(cx) { | ||
| return Poll::Ready((*i, v)); | ||
| } | ||
| } | ||
|
|
||
| Poll::Pending | ||
| } | ||
| } | ||
|
|
||
| pub fn select_slice<'a, F, O>( | ||
| futures: &'a mut [F], | ||
| scratch: &'a mut Vec<usize>, | ||
| ) -> SelectSliceFuture<'a, F> | ||
| where | ||
| F: Future<Output = O> + Unpin, | ||
| { | ||
| if futures.len() > scratch.capacity() { | ||
| panic!( | ||
| "select_slice scratch is not large enough: {}, need {}", | ||
| scratch.capacity(), | ||
| futures.len() | ||
| ); | ||
| } | ||
|
|
||
| SelectSliceFuture { futures, scratch } | ||
| } | ||
|
|
||
| pub struct SelectOptionFuture<F> { | ||
| fut: Option<F>, | ||
| } | ||
|
|
||
| impl<F, O> Future for SelectOptionFuture<F> | ||
| where | ||
| F: Future<Output = O> + Unpin, | ||
| { | ||
| type Output = O; | ||
|
|
||
| fn poll(mut self: Pin<&mut Self>, cx: &mut Context) -> Poll<Self::Output> { | ||
| let s = &mut *self; | ||
|
|
||
| match Pin::new(&mut s.fut).as_pin_mut() { | ||
| Some(f) => f.poll(cx), | ||
| None => Poll::Pending, | ||
| } | ||
| } | ||
| } | ||
|
|
||
| pub fn select_option<F, O>(fut: Option<F>) -> SelectOptionFuture<F> | ||
| where | ||
| F: Future<Output = O>, | ||
| { | ||
| SelectOptionFuture { fut } | ||
| } |
Oops, something went wrong.