| <!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/incubator-teaclave-crates-c8106113f74feefc/ede1f68/mio/src/token.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>token.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="../../mio/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="../../mio/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="doccomment">/// Associates readiness events with [`event::Source`]s. |
| /// |
| /// `Token` is a wrapper around `usize` and is used as an argument to |
| /// [`Registry::register`] and [`Registry::reregister`]. |
| /// |
| /// See [`Poll`] for more documentation on polling. |
| /// |
| /// [`event::Source`]: ./event/trait.Source.html |
| /// [`Poll`]: struct.Poll.html |
| /// [`Registry::register`]: struct.Registry.html#method.register |
| /// [`Registry::reregister`]: struct.Registry.html#method.reregister |
| /// |
| /// # Example |
| /// |
| /// Using `Token` to track which socket generated the event. In this example, |
| /// `HashMap` is used, but usually something like [`slab`] is better. |
| /// |
| /// [`slab`]: https://crates.io/crates/slab |
| /// |
| </span><span class="attribute">#[cfg_attr(all(feature = <span class="string">"os-poll"</span>, feature = <span class="string">"net"</span>), doc = <span class="string">"```"</span>)] |
| #[cfg_attr(not(all(feature = <span class="string">"os-poll"</span>, feature = <span class="string">"net"</span>)), doc = <span class="string">"```ignore"</span>)] |
| </span><span class="doccomment">/// # use std::error::Error; |
| /// # fn main() -> Result<(), Box<dyn Error>> { |
| /// use mio::{Events, Interest, Poll, Token}; |
| /// use mio::net::TcpListener; |
| /// |
| /// use std::thread; |
| /// use std::io::{self, Read}; |
| /// use std::collections::HashMap; |
| /// |
| /// // After this number of sockets is accepted, the server will shutdown. |
| /// const MAX_SOCKETS: usize = 32; |
| /// |
| /// // Pick a token that will not be used by any other socket and use that one |
| /// // for the listener. |
| /// const LISTENER: Token = Token(1024); |
| /// |
| /// // Used to store the sockets. |
| /// let mut sockets = HashMap::new(); |
| /// |
| /// // This is used to generate a unique token for a socket |
| /// let mut next_socket_index = 0; |
| /// |
| /// // The `Poll` instance |
| /// let mut poll = Poll::new()?; |
| /// |
| /// // Tcp listener |
| /// let mut listener = TcpListener::bind("127.0.0.1:0".parse()?)?; |
| /// |
| /// // Register the listener |
| /// poll.registry().register(&mut listener, LISTENER, Interest::READABLE)?; |
| /// |
| /// // Spawn a thread that will connect a bunch of sockets then close them |
| /// let addr = listener.local_addr()?; |
| /// thread::spawn(move || { |
| /// use std::net::TcpStream; |
| /// |
| /// // +1 here is to connect an extra socket to signal the socket to close |
| /// for _ in 0..(MAX_SOCKETS+1) { |
| /// // Connect then drop the socket |
| /// let _ = TcpStream::connect(addr).unwrap(); |
| /// } |
| /// }); |
| /// |
| /// // Event storage |
| /// let mut events = Events::with_capacity(1024); |
| /// |
| /// // Read buffer, this will never actually get filled |
| /// let mut buf = [0; 256]; |
| /// |
| /// // The main event loop |
| /// loop { |
| /// // Wait for events |
| /// poll.poll(&mut events, None)?; |
| /// |
| /// for event in &events { |
| /// match event.token() { |
| /// LISTENER => { |
| /// // Perform operations in a loop until `WouldBlock` is |
| /// // encountered. |
| /// loop { |
| /// match listener.accept() { |
| /// Ok((mut socket, _)) => { |
| /// // Shutdown the server |
| /// if next_socket_index == MAX_SOCKETS { |
| /// return Ok(()); |
| /// } |
| /// |
| /// // Get the token for the socket |
| /// let token = Token(next_socket_index); |
| /// next_socket_index += 1; |
| /// |
| /// // Register the new socket w/ poll |
| /// poll.registry().register(&mut socket, token, Interest::READABLE)?; |
| /// |
| /// // Store the socket |
| /// sockets.insert(token, socket); |
| /// } |
| /// Err(ref e) if e.kind() == io::ErrorKind::WouldBlock => { |
| /// // Socket is not ready anymore, stop accepting |
| /// break; |
| /// } |
| /// e => panic!("err={:?}", e), // Unexpected error |
| /// } |
| /// } |
| /// } |
| /// token => { |
| /// // Always operate in a loop |
| /// loop { |
| /// match sockets.get_mut(&token).unwrap().read(&mut buf) { |
| /// Ok(0) => { |
| /// // Socket is closed, remove it from the map |
| /// sockets.remove(&token); |
| /// break; |
| /// } |
| /// // Data is not actually sent in this example |
| /// Ok(_) => unreachable!(), |
| /// Err(ref e) if e.kind() == io::ErrorKind::WouldBlock => { |
| /// // Socket is not ready anymore, stop reading |
| /// break; |
| /// } |
| /// e => panic!("err={:?}", e), // Unexpected error |
| /// } |
| /// } |
| /// } |
| /// } |
| /// } |
| /// } |
| /// # } |
| /// ``` |
| </span><span class="attribute">#[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord, Hash)] |
| </span><span class="kw">pub struct </span>Token(<span class="kw">pub </span>usize); |
| |
| <span class="kw">impl </span>From<Token> <span class="kw">for </span>usize { |
| <span class="kw">fn </span>from(val: Token) -> usize { |
| val.<span class="number">0 |
| </span>} |
| } |
| </code></pre></div> |
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