| <!DOCTYPE html><html lang="en"><head><meta charset="utf-8"><meta name="viewport" content="width=device-width, initial-scale=1.0"><meta name="generator" content="rustdoc"><meta name="description" content="Source of the Rust file `/root/.cargo/git/checkouts/tokio-377c595163f99a10/dfe252d/tokio/src/sync/mpsc/chan.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>chan.rs - source</title><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../../SourceSerif4-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../../FiraSans-Regular.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../../FiraSans-Medium.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../../SourceCodePro-Regular.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../../SourceSerif4-Bold.ttf.woff2"><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../../SourceCodePro-Semibold.ttf.woff2"><link rel="stylesheet" href="../../../../normalize.css"><link rel="stylesheet" href="../../../../rustdoc.css" id="mainThemeStyle"><link rel="stylesheet" href="../../../../ayu.css" disabled><link rel="stylesheet" href="../../../../dark.css" disabled><link rel="stylesheet" href="../../../../light.css" id="themeStyle"><script id="default-settings" ></script><script src="../../../../storage.js"></script><script defer src="../../../../source-script.js"></script><script defer src="../../../../source-files.js"></script><script defer src="../../../../main.js"></script><noscript><link rel="stylesheet" href="../../../../noscript.css"></noscript><link rel="alternate icon" type="image/png" href="../../../../favicon-16x16.png"><link rel="alternate icon" type="image/png" href="../../../../favicon-32x32.png"><link rel="icon" type="image/svg+xml" href="../../../../favicon.svg"></head><body class="rustdoc source"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><nav class="sidebar"><a class="sidebar-logo" href="../../../../tokio/index.html"><div class="logo-container"><img class="rust-logo" src="../../../../rust-logo.svg" alt="logo"></div></a></nav><main><div class="width-limiter"><nav class="sub"><a class="sub-logo-container" href="../../../../tokio/index.html"><img class="rust-logo" src="../../../../rust-logo.svg" alt="logo"></a><form class="search-form"><div class="search-container"><span></span><input class="search-input" name="search" autocomplete="off" spellcheck="false" placeholder="Click or press ‘S’ to search, ‘?’ for more options…" type="search"><div id="help-button" title="help" tabindex="-1"><a href="../../../../help.html">?</a></div><div id="settings-menu" tabindex="-1"><a href="../../../../settings.html" title="settings"><img width="22" height="22" alt="Change settings" src="../../../../wheel.svg"></a></div></div></form></nav><section id="main-content" class="content"><div class="example-wrap"><pre class="src-line-numbers"><span id="1">1</span> |
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| </pre><pre class="rust"><code><span class="kw">use </span><span class="kw">crate</span>::loom::cell::UnsafeCell; |
| <span class="kw">use </span><span class="kw">crate</span>::loom::future::AtomicWaker; |
| <span class="kw">use </span><span class="kw">crate</span>::loom::sync::atomic::AtomicUsize; |
| <span class="kw">use </span><span class="kw">crate</span>::loom::sync::Arc; |
| <span class="kw">use </span><span class="kw">crate</span>::runtime::park::CachedParkThread; |
| <span class="kw">use </span><span class="kw">crate</span>::sync::mpsc::error::TryRecvError; |
| <span class="kw">use </span><span class="kw">crate</span>::sync::mpsc::{bounded, list, unbounded}; |
| <span class="kw">use </span><span class="kw">crate</span>::sync::notify::Notify; |
| |
| <span class="kw">use </span>std::fmt; |
| <span class="kw">use </span>std::process; |
| <span class="kw">use </span>std::sync::atomic::Ordering::{AcqRel, Acquire, Relaxed, Release}; |
| <span class="kw">use </span>std::task::Poll::{Pending, Ready}; |
| <span class="kw">use </span>std::task::{Context, Poll}; |
| |
| <span class="doccomment">/// Channel sender. |
| </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">struct </span>Tx<T, S> { |
| inner: Arc<Chan<T, S>>, |
| } |
| |
| <span class="kw">impl</span><T, S: fmt::Debug> fmt::Debug <span class="kw">for </span>Tx<T, S> { |
| <span class="kw">fn </span>fmt(<span class="kw-2">&</span><span class="self">self</span>, fmt: <span class="kw-2">&mut </span>fmt::Formatter<<span class="lifetime">'_</span>>) -> fmt::Result { |
| fmt.debug_struct(<span class="string">"Tx"</span>).field(<span class="string">"inner"</span>, <span class="kw-2">&</span><span class="self">self</span>.inner).finish() |
| } |
| } |
| |
| <span class="doccomment">/// Channel receiver. |
| </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">struct </span>Rx<T, S: Semaphore> { |
| inner: Arc<Chan<T, S>>, |
| } |
| |
| <span class="kw">impl</span><T, S: Semaphore + fmt::Debug> fmt::Debug <span class="kw">for </span>Rx<T, S> { |
| <span class="kw">fn </span>fmt(<span class="kw-2">&</span><span class="self">self</span>, fmt: <span class="kw-2">&mut </span>fmt::Formatter<<span class="lifetime">'_</span>>) -> fmt::Result { |
| fmt.debug_struct(<span class="string">"Rx"</span>).field(<span class="string">"inner"</span>, <span class="kw-2">&</span><span class="self">self</span>.inner).finish() |
| } |
| } |
| |
| <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">trait </span>Semaphore { |
| <span class="kw">fn </span>is_idle(<span class="kw-2">&</span><span class="self">self</span>) -> bool; |
| |
| <span class="kw">fn </span>add_permit(<span class="kw-2">&</span><span class="self">self</span>); |
| |
| <span class="kw">fn </span>close(<span class="kw-2">&</span><span class="self">self</span>); |
| |
| <span class="kw">fn </span>is_closed(<span class="kw-2">&</span><span class="self">self</span>) -> bool; |
| } |
| |
| <span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">struct </span>Chan<T, S> { |
| <span class="doccomment">/// Notifies all tasks listening for the receiver being dropped. |
| </span>notify_rx_closed: Notify, |
| |
| <span class="doccomment">/// Handle to the push half of the lock-free list. |
| </span>tx: list::Tx<T>, |
| |
| <span class="doccomment">/// Coordinates access to channel's capacity. |
| </span>semaphore: S, |
| |
| <span class="doccomment">/// Receiver waker. Notified when a value is pushed into the channel. |
| </span>rx_waker: AtomicWaker, |
| |
| <span class="doccomment">/// Tracks the number of outstanding sender handles. |
| /// |
| /// When this drops to zero, the send half of the channel is closed. |
| </span>tx_count: AtomicUsize, |
| |
| <span class="doccomment">/// Only accessed by `Rx` handle. |
| </span>rx_fields: UnsafeCell<RxFields<T>>, |
| } |
| |
| <span class="kw">impl</span><T, S> fmt::Debug <span class="kw">for </span>Chan<T, S> |
| <span class="kw">where |
| </span>S: fmt::Debug, |
| { |
| <span class="kw">fn </span>fmt(<span class="kw-2">&</span><span class="self">self</span>, fmt: <span class="kw-2">&mut </span>fmt::Formatter<<span class="lifetime">'_</span>>) -> fmt::Result { |
| fmt.debug_struct(<span class="string">"Chan"</span>) |
| .field(<span class="string">"tx"</span>, <span class="kw-2">&</span><span class="self">self</span>.tx) |
| .field(<span class="string">"semaphore"</span>, <span class="kw-2">&</span><span class="self">self</span>.semaphore) |
| .field(<span class="string">"rx_waker"</span>, <span class="kw-2">&</span><span class="self">self</span>.rx_waker) |
| .field(<span class="string">"tx_count"</span>, <span class="kw-2">&</span><span class="self">self</span>.tx_count) |
| .field(<span class="string">"rx_fields"</span>, <span class="kw-2">&</span><span class="string">"..."</span>) |
| .finish() |
| } |
| } |
| |
| <span class="doccomment">/// Fields only accessed by `Rx` handle. |
| </span><span class="kw">struct </span>RxFields<T> { |
| <span class="doccomment">/// Channel receiver. This field is only accessed by the `Receiver` type. |
| </span>list: list::Rx<T>, |
| |
| <span class="doccomment">/// `true` if `Rx::close` is called. |
| </span>rx_closed: bool, |
| } |
| |
| <span class="kw">impl</span><T> fmt::Debug <span class="kw">for </span>RxFields<T> { |
| <span class="kw">fn </span>fmt(<span class="kw-2">&</span><span class="self">self</span>, fmt: <span class="kw-2">&mut </span>fmt::Formatter<<span class="lifetime">'_</span>>) -> fmt::Result { |
| fmt.debug_struct(<span class="string">"RxFields"</span>) |
| .field(<span class="string">"list"</span>, <span class="kw-2">&</span><span class="self">self</span>.list) |
| .field(<span class="string">"rx_closed"</span>, <span class="kw-2">&</span><span class="self">self</span>.rx_closed) |
| .finish() |
| } |
| } |
| |
| <span class="kw">unsafe impl</span><T: Send, S: Send> Send <span class="kw">for </span>Chan<T, S> {} |
| <span class="kw">unsafe impl</span><T: Send, S: Sync> Sync <span class="kw">for </span>Chan<T, S> {} |
| |
| <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>channel<T, S: Semaphore>(semaphore: S) -> (Tx<T, S>, Rx<T, S>) { |
| <span class="kw">let </span>(tx, rx) = list::channel(); |
| |
| <span class="kw">let </span>chan = Arc::new(Chan { |
| notify_rx_closed: Notify::new(), |
| tx, |
| semaphore, |
| rx_waker: AtomicWaker::new(), |
| tx_count: AtomicUsize::new(<span class="number">1</span>), |
| rx_fields: UnsafeCell::new(RxFields { |
| list: rx, |
| rx_closed: <span class="bool-val">false</span>, |
| }), |
| }); |
| |
| (Tx::new(chan.clone()), Rx::new(chan)) |
| } |
| |
| <span class="comment">// ===== impl Tx ===== |
| |
| </span><span class="kw">impl</span><T, S> Tx<T, S> { |
| <span class="kw">fn </span>new(chan: Arc<Chan<T, S>>) -> Tx<T, S> { |
| Tx { inner: chan } |
| } |
| |
| <span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">fn </span>downgrade(<span class="kw-2">&</span><span class="self">self</span>) -> Arc<Chan<T, S>> { |
| <span class="self">self</span>.inner.clone() |
| } |
| |
| <span class="comment">// Returns the upgraded channel or None if the upgrade failed. |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">fn </span>upgrade(chan: Arc<Chan<T, S>>) -> <span class="prelude-ty">Option</span><<span class="self">Self</span>> { |
| <span class="kw">let </span><span class="kw-2">mut </span>tx_count = chan.tx_count.load(Acquire); |
| |
| <span class="kw">loop </span>{ |
| <span class="kw">if </span>tx_count == <span class="number">0 </span>{ |
| <span class="comment">// channel is closed |
| </span><span class="kw">return </span><span class="prelude-val">None</span>; |
| } |
| |
| <span class="kw">match </span>chan |
| .tx_count |
| .compare_exchange_weak(tx_count, tx_count + <span class="number">1</span>, AcqRel, Acquire) |
| { |
| <span class="prelude-val">Ok</span>(<span class="kw">_</span>) => <span class="kw">return </span><span class="prelude-val">Some</span>(Tx { inner: chan }), |
| <span class="prelude-val">Err</span>(prev_count) => tx_count = prev_count, |
| } |
| } |
| } |
| |
| <span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">fn </span>semaphore(<span class="kw-2">&</span><span class="self">self</span>) -> <span class="kw-2">&</span>S { |
| <span class="kw-2">&</span><span class="self">self</span>.inner.semaphore |
| } |
| |
| <span class="doccomment">/// Send a message and notify the receiver. |
| </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>send(<span class="kw-2">&</span><span class="self">self</span>, value: T) { |
| <span class="self">self</span>.inner.send(value); |
| } |
| |
| <span class="doccomment">/// Wake the receive half |
| </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>wake_rx(<span class="kw-2">&</span><span class="self">self</span>) { |
| <span class="self">self</span>.inner.rx_waker.wake(); |
| } |
| |
| <span class="doccomment">/// Returns `true` if senders belong to the same channel. |
| </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>same_channel(<span class="kw-2">&</span><span class="self">self</span>, other: <span class="kw-2">&</span><span class="self">Self</span>) -> bool { |
| Arc::ptr_eq(<span class="kw-2">&</span><span class="self">self</span>.inner, <span class="kw-2">&</span>other.inner) |
| } |
| } |
| |
| <span class="kw">impl</span><T, S: Semaphore> Tx<T, S> { |
| <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>is_closed(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| <span class="self">self</span>.inner.semaphore.is_closed() |
| } |
| |
| <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">async fn </span>closed(<span class="kw-2">&</span><span class="self">self</span>) { |
| <span class="comment">// In order to avoid a race condition, we first request a notification, |
| // **then** check whether the semaphore is closed. If the semaphore is |
| // closed the notification request is dropped. |
| </span><span class="kw">let </span>notified = <span class="self">self</span>.inner.notify_rx_closed.notified(); |
| |
| <span class="kw">if </span><span class="self">self</span>.inner.semaphore.is_closed() { |
| <span class="kw">return</span>; |
| } |
| notified.<span class="kw">await</span>; |
| } |
| } |
| |
| <span class="kw">impl</span><T, S> Clone <span class="kw">for </span>Tx<T, S> { |
| <span class="kw">fn </span>clone(<span class="kw-2">&</span><span class="self">self</span>) -> Tx<T, S> { |
| <span class="comment">// Using a Relaxed ordering here is sufficient as the caller holds a |
| // strong ref to `self`, preventing a concurrent decrement to zero. |
| </span><span class="self">self</span>.inner.tx_count.fetch_add(<span class="number">1</span>, Relaxed); |
| |
| Tx { |
| inner: <span class="self">self</span>.inner.clone(), |
| } |
| } |
| } |
| |
| <span class="kw">impl</span><T, S> Drop <span class="kw">for </span>Tx<T, S> { |
| <span class="kw">fn </span>drop(<span class="kw-2">&mut </span><span class="self">self</span>) { |
| <span class="kw">if </span><span class="self">self</span>.inner.tx_count.fetch_sub(<span class="number">1</span>, AcqRel) != <span class="number">1 </span>{ |
| <span class="kw">return</span>; |
| } |
| |
| <span class="comment">// Close the list, which sends a `Close` message |
| </span><span class="self">self</span>.inner.tx.close(); |
| |
| <span class="comment">// Notify the receiver |
| </span><span class="self">self</span>.wake_rx(); |
| } |
| } |
| |
| <span class="comment">// ===== impl Rx ===== |
| |
| </span><span class="kw">impl</span><T, S: Semaphore> Rx<T, S> { |
| <span class="kw">fn </span>new(chan: Arc<Chan<T, S>>) -> Rx<T, S> { |
| Rx { inner: chan } |
| } |
| |
| <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>close(<span class="kw-2">&mut </span><span class="self">self</span>) { |
| <span class="self">self</span>.inner.rx_fields.with_mut(|rx_fields_ptr| { |
| <span class="kw">let </span>rx_fields = <span class="kw">unsafe </span>{ <span class="kw-2">&mut *</span>rx_fields_ptr }; |
| |
| <span class="kw">if </span>rx_fields.rx_closed { |
| <span class="kw">return</span>; |
| } |
| |
| rx_fields.rx_closed = <span class="bool-val">true</span>; |
| }); |
| |
| <span class="self">self</span>.inner.semaphore.close(); |
| <span class="self">self</span>.inner.notify_rx_closed.notify_waiters(); |
| } |
| |
| <span class="doccomment">/// Receive the next value |
| </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>recv(<span class="kw-2">&mut </span><span class="self">self</span>, cx: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>) -> Poll<<span class="prelude-ty">Option</span><T>> { |
| <span class="kw">use </span><span class="kw">super</span>::block::Read::<span class="kw-2">*</span>; |
| |
| <span class="comment">// Keep track of task budget |
| </span><span class="kw">let </span>coop = <span class="macro">ready!</span>(<span class="kw">crate</span>::runtime::coop::poll_proceed(cx)); |
| |
| <span class="self">self</span>.inner.rx_fields.with_mut(|rx_fields_ptr| { |
| <span class="kw">let </span>rx_fields = <span class="kw">unsafe </span>{ <span class="kw-2">&mut *</span>rx_fields_ptr }; |
| |
| <span class="macro">macro_rules! </span>try_recv { |
| () => { |
| <span class="kw">match </span>rx_fields.list.pop(<span class="kw-2">&</span><span class="self">self</span>.inner.tx) { |
| <span class="prelude-val">Some</span>(Value(value)) => { |
| <span class="self">self</span>.inner.semaphore.add_permit(); |
| coop.made_progress(); |
| <span class="kw">return </span>Ready(<span class="prelude-val">Some</span>(value)); |
| } |
| <span class="prelude-val">Some</span>(Closed) => { |
| <span class="comment">// TODO: This check may not be required as it most |
| // likely can only return `true` at this point. A |
| // channel is closed when all tx handles are |
| // dropped. Dropping a tx handle releases memory, |
| // which ensures that if dropping the tx handle is |
| // visible, then all messages sent are also visible. |
| </span><span class="macro">assert!</span>(<span class="self">self</span>.inner.semaphore.is_idle()); |
| coop.made_progress(); |
| <span class="kw">return </span>Ready(<span class="prelude-val">None</span>); |
| } |
| <span class="prelude-val">None </span>=> {} <span class="comment">// fall through |
| </span>} |
| }; |
| } |
| |
| <span class="macro">try_recv!</span>(); |
| |
| <span class="self">self</span>.inner.rx_waker.register_by_ref(cx.waker()); |
| |
| <span class="comment">// It is possible that a value was pushed between attempting to read |
| // and registering the task, so we have to check the channel a |
| // second time here. |
| </span><span class="macro">try_recv!</span>(); |
| |
| <span class="kw">if </span>rx_fields.rx_closed && <span class="self">self</span>.inner.semaphore.is_idle() { |
| coop.made_progress(); |
| Ready(<span class="prelude-val">None</span>) |
| } <span class="kw">else </span>{ |
| Pending |
| } |
| }) |
| } |
| |
| <span class="doccomment">/// Try to receive the next value. |
| </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>try_recv(<span class="kw-2">&mut </span><span class="self">self</span>) -> <span class="prelude-ty">Result</span><T, TryRecvError> { |
| <span class="kw">use </span><span class="kw">super</span>::list::TryPopResult; |
| |
| <span class="self">self</span>.inner.rx_fields.with_mut(|rx_fields_ptr| { |
| <span class="kw">let </span>rx_fields = <span class="kw">unsafe </span>{ <span class="kw-2">&mut *</span>rx_fields_ptr }; |
| |
| <span class="macro">macro_rules! </span>try_recv { |
| () => { |
| <span class="kw">match </span>rx_fields.list.try_pop(<span class="kw-2">&</span><span class="self">self</span>.inner.tx) { |
| TryPopResult::Ok(value) => { |
| <span class="self">self</span>.inner.semaphore.add_permit(); |
| <span class="kw">return </span><span class="prelude-val">Ok</span>(value); |
| } |
| TryPopResult::Closed => <span class="kw">return </span><span class="prelude-val">Err</span>(TryRecvError::Disconnected), |
| TryPopResult::Empty => <span class="kw">return </span><span class="prelude-val">Err</span>(TryRecvError::Empty), |
| TryPopResult::Busy => {} <span class="comment">// fall through |
| </span>} |
| }; |
| } |
| |
| <span class="macro">try_recv!</span>(); |
| |
| <span class="comment">// If a previous `poll_recv` call has set a waker, we wake it here. |
| // This allows us to put our own CachedParkThread waker in the |
| // AtomicWaker slot instead. |
| // |
| // This is not a spurious wakeup to `poll_recv` since we just got a |
| // Busy from `try_pop`, which only happens if there are messages in |
| // the queue. |
| </span><span class="self">self</span>.inner.rx_waker.wake(); |
| |
| <span class="comment">// Park the thread until the problematic send has completed. |
| </span><span class="kw">let </span><span class="kw-2">mut </span>park = CachedParkThread::new(); |
| <span class="kw">let </span>waker = park.waker().unwrap(); |
| <span class="kw">loop </span>{ |
| <span class="self">self</span>.inner.rx_waker.register_by_ref(<span class="kw-2">&</span>waker); |
| <span class="comment">// It is possible that the problematic send has now completed, |
| // so we have to check for messages again. |
| </span><span class="macro">try_recv!</span>(); |
| park.park(); |
| } |
| }) |
| } |
| } |
| |
| <span class="kw">impl</span><T, S: Semaphore> Drop <span class="kw">for </span>Rx<T, S> { |
| <span class="kw">fn </span>drop(<span class="kw-2">&mut </span><span class="self">self</span>) { |
| <span class="kw">use </span><span class="kw">super</span>::block::Read::Value; |
| |
| <span class="self">self</span>.close(); |
| |
| <span class="self">self</span>.inner.rx_fields.with_mut(|rx_fields_ptr| { |
| <span class="kw">let </span>rx_fields = <span class="kw">unsafe </span>{ <span class="kw-2">&mut *</span>rx_fields_ptr }; |
| |
| <span class="kw">while let </span><span class="prelude-val">Some</span>(Value(<span class="kw">_</span>)) = rx_fields.list.pop(<span class="kw-2">&</span><span class="self">self</span>.inner.tx) { |
| <span class="self">self</span>.inner.semaphore.add_permit(); |
| } |
| }) |
| } |
| } |
| |
| <span class="comment">// ===== impl Chan ===== |
| |
| </span><span class="kw">impl</span><T, S> Chan<T, S> { |
| <span class="kw">fn </span>send(<span class="kw-2">&</span><span class="self">self</span>, value: T) { |
| <span class="comment">// Push the value |
| </span><span class="self">self</span>.tx.push(value); |
| |
| <span class="comment">// Notify the rx task |
| </span><span class="self">self</span>.rx_waker.wake(); |
| } |
| } |
| |
| <span class="kw">impl</span><T, S> Drop <span class="kw">for </span>Chan<T, S> { |
| <span class="kw">fn </span>drop(<span class="kw-2">&mut </span><span class="self">self</span>) { |
| <span class="kw">use </span><span class="kw">super</span>::block::Read::Value; |
| |
| <span class="comment">// Safety: the only owner of the rx fields is Chan, and being |
| // inside its own Drop means we're the last ones to touch it. |
| </span><span class="self">self</span>.rx_fields.with_mut(|rx_fields_ptr| { |
| <span class="kw">let </span>rx_fields = <span class="kw">unsafe </span>{ <span class="kw-2">&mut *</span>rx_fields_ptr }; |
| |
| <span class="kw">while let </span><span class="prelude-val">Some</span>(Value(<span class="kw">_</span>)) = rx_fields.list.pop(<span class="kw-2">&</span><span class="self">self</span>.tx) {} |
| <span class="kw">unsafe </span>{ rx_fields.list.free_blocks() }; |
| }); |
| } |
| } |
| |
| <span class="comment">// ===== impl Semaphore for (::Semaphore, capacity) ===== |
| |
| </span><span class="kw">impl </span>Semaphore <span class="kw">for </span>bounded::Semaphore { |
| <span class="kw">fn </span>add_permit(<span class="kw-2">&</span><span class="self">self</span>) { |
| <span class="self">self</span>.semaphore.release(<span class="number">1</span>) |
| } |
| |
| <span class="kw">fn </span>is_idle(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| <span class="self">self</span>.semaphore.available_permits() == <span class="self">self</span>.bound |
| } |
| |
| <span class="kw">fn </span>close(<span class="kw-2">&</span><span class="self">self</span>) { |
| <span class="self">self</span>.semaphore.close(); |
| } |
| |
| <span class="kw">fn </span>is_closed(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| <span class="self">self</span>.semaphore.is_closed() |
| } |
| } |
| |
| <span class="comment">// ===== impl Semaphore for AtomicUsize ===== |
| |
| </span><span class="kw">impl </span>Semaphore <span class="kw">for </span>unbounded::Semaphore { |
| <span class="kw">fn </span>add_permit(<span class="kw-2">&</span><span class="self">self</span>) { |
| <span class="kw">let </span>prev = <span class="self">self</span>.<span class="number">0</span>.fetch_sub(<span class="number">2</span>, Release); |
| |
| <span class="kw">if </span>prev >> <span class="number">1 </span>== <span class="number">0 </span>{ |
| <span class="comment">// Something went wrong |
| </span>process::abort(); |
| } |
| } |
| |
| <span class="kw">fn </span>is_idle(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| <span class="self">self</span>.<span class="number">0</span>.load(Acquire) >> <span class="number">1 </span>== <span class="number">0 |
| </span>} |
| |
| <span class="kw">fn </span>close(<span class="kw-2">&</span><span class="self">self</span>) { |
| <span class="self">self</span>.<span class="number">0</span>.fetch_or(<span class="number">1</span>, Release); |
| } |
| |
| <span class="kw">fn </span>is_closed(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| <span class="self">self</span>.<span class="number">0</span>.load(Acquire) & <span class="number">1 </span>== <span class="number">1 |
| </span>} |
| } |
| </code></pre></div> |
| </section></div></main><div id="rustdoc-vars" data-root-path="../../../../" data-current-crate="tokio" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0-nightly (5c8bff74b 2022-10-21)" ></div></body></html> |
