| <!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/registry/src/github.com-1ecc6299db9ec823/h2-0.3.19/src/proto/go_away.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>go_away.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="../../../h2/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="../../../h2/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> |
| <span id="2">2</span> |
| <span id="3">3</span> |
| <span id="4">4</span> |
| <span id="5">5</span> |
| <span id="6">6</span> |
| <span id="7">7</span> |
| <span id="8">8</span> |
| <span id="9">9</span> |
| <span id="10">10</span> |
| <span id="11">11</span> |
| <span id="12">12</span> |
| <span id="13">13</span> |
| <span id="14">14</span> |
| <span id="15">15</span> |
| <span id="16">16</span> |
| <span id="17">17</span> |
| <span id="18">18</span> |
| <span id="19">19</span> |
| <span id="20">20</span> |
| <span id="21">21</span> |
| <span id="22">22</span> |
| <span id="23">23</span> |
| <span id="24">24</span> |
| <span id="25">25</span> |
| <span id="26">26</span> |
| <span id="27">27</span> |
| <span id="28">28</span> |
| <span id="29">29</span> |
| <span id="30">30</span> |
| <span id="31">31</span> |
| <span id="32">32</span> |
| <span id="33">33</span> |
| <span id="34">34</span> |
| <span id="35">35</span> |
| <span id="36">36</span> |
| <span id="37">37</span> |
| <span id="38">38</span> |
| <span id="39">39</span> |
| <span id="40">40</span> |
| <span id="41">41</span> |
| <span id="42">42</span> |
| <span id="43">43</span> |
| <span id="44">44</span> |
| <span id="45">45</span> |
| <span id="46">46</span> |
| <span id="47">47</span> |
| <span id="48">48</span> |
| <span id="49">49</span> |
| <span id="50">50</span> |
| <span id="51">51</span> |
| <span id="52">52</span> |
| <span id="53">53</span> |
| <span id="54">54</span> |
| <span id="55">55</span> |
| <span id="56">56</span> |
| <span id="57">57</span> |
| <span id="58">58</span> |
| <span id="59">59</span> |
| <span id="60">60</span> |
| <span id="61">61</span> |
| <span id="62">62</span> |
| <span id="63">63</span> |
| <span id="64">64</span> |
| <span id="65">65</span> |
| <span id="66">66</span> |
| <span id="67">67</span> |
| <span id="68">68</span> |
| <span id="69">69</span> |
| <span id="70">70</span> |
| <span id="71">71</span> |
| <span id="72">72</span> |
| <span id="73">73</span> |
| <span id="74">74</span> |
| <span id="75">75</span> |
| <span id="76">76</span> |
| <span id="77">77</span> |
| <span id="78">78</span> |
| <span id="79">79</span> |
| <span id="80">80</span> |
| <span id="81">81</span> |
| <span id="82">82</span> |
| <span id="83">83</span> |
| <span id="84">84</span> |
| <span id="85">85</span> |
| <span id="86">86</span> |
| <span id="87">87</span> |
| <span id="88">88</span> |
| <span id="89">89</span> |
| <span id="90">90</span> |
| <span id="91">91</span> |
| <span id="92">92</span> |
| <span id="93">93</span> |
| <span id="94">94</span> |
| <span id="95">95</span> |
| <span id="96">96</span> |
| <span id="97">97</span> |
| <span id="98">98</span> |
| <span id="99">99</span> |
| <span id="100">100</span> |
| <span id="101">101</span> |
| <span id="102">102</span> |
| <span id="103">103</span> |
| <span id="104">104</span> |
| <span id="105">105</span> |
| <span id="106">106</span> |
| <span id="107">107</span> |
| <span id="108">108</span> |
| <span id="109">109</span> |
| <span id="110">110</span> |
| <span id="111">111</span> |
| <span id="112">112</span> |
| <span id="113">113</span> |
| <span id="114">114</span> |
| <span id="115">115</span> |
| <span id="116">116</span> |
| <span id="117">117</span> |
| <span id="118">118</span> |
| <span id="119">119</span> |
| <span id="120">120</span> |
| <span id="121">121</span> |
| <span id="122">122</span> |
| <span id="123">123</span> |
| <span id="124">124</span> |
| <span id="125">125</span> |
| <span id="126">126</span> |
| <span id="127">127</span> |
| <span id="128">128</span> |
| <span id="129">129</span> |
| <span id="130">130</span> |
| <span id="131">131</span> |
| <span id="132">132</span> |
| <span id="133">133</span> |
| <span id="134">134</span> |
| <span id="135">135</span> |
| <span id="136">136</span> |
| <span id="137">137</span> |
| <span id="138">138</span> |
| <span id="139">139</span> |
| <span id="140">140</span> |
| <span id="141">141</span> |
| <span id="142">142</span> |
| <span id="143">143</span> |
| <span id="144">144</span> |
| <span id="145">145</span> |
| <span id="146">146</span> |
| <span id="147">147</span> |
| <span id="148">148</span> |
| <span id="149">149</span> |
| <span id="150">150</span> |
| <span id="151">151</span> |
| <span id="152">152</span> |
| <span id="153">153</span> |
| <span id="154">154</span> |
| </pre><pre class="rust"><code><span class="kw">use </span><span class="kw">crate</span>::codec::Codec; |
| <span class="kw">use </span><span class="kw">crate</span>::frame::{<span class="self">self</span>, Reason, StreamId}; |
| |
| <span class="kw">use </span>bytes::Buf; |
| <span class="kw">use </span>std::io; |
| <span class="kw">use </span>std::task::{Context, Poll}; |
| <span class="kw">use </span>tokio::io::AsyncWrite; |
| |
| <span class="doccomment">/// Manages our sending of GOAWAY frames. |
| </span><span class="attribute">#[derive(Debug)] |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">struct </span>GoAway { |
| <span class="doccomment">/// Whether the connection should close now, or wait until idle. |
| </span>close_now: bool, |
| <span class="doccomment">/// Records if we've sent any GOAWAY before. |
| </span>going_away: <span class="prelude-ty">Option</span><GoingAway>, |
| <span class="doccomment">/// Whether the user started the GOAWAY by calling `abrupt_shutdown`. |
| </span>is_user_initiated: bool, |
| <span class="doccomment">/// A GOAWAY frame that must be buffered in the Codec immediately. |
| </span>pending: <span class="prelude-ty">Option</span><frame::GoAway>, |
| } |
| |
| <span class="doccomment">/// Keeps a memory of any GOAWAY frames we've sent before. |
| /// |
| /// This looks very similar to a `frame::GoAway`, but is a separate type. Why? |
| /// Mostly for documentation purposes. This type is to record status. If it |
| /// were a `frame::GoAway`, it might appear like we eventually wanted to |
| /// serialize it. We **only** want to be able to look up these fields at a |
| /// later time. |
| </span><span class="attribute">#[derive(Debug)] |
| </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">struct </span>GoingAway { |
| <span class="doccomment">/// Stores the highest stream ID of a GOAWAY that has been sent. |
| /// |
| /// It's illegal to send a subsequent GOAWAY with a higher ID. |
| </span>last_processed_id: StreamId, |
| |
| <span class="doccomment">/// Records the error code of any GOAWAY frame sent. |
| </span>reason: Reason, |
| } |
| |
| <span class="kw">impl </span>GoAway { |
| <span class="kw">pub fn </span>new() -> <span class="self">Self </span>{ |
| GoAway { |
| close_now: <span class="bool-val">false</span>, |
| going_away: <span class="prelude-val">None</span>, |
| is_user_initiated: <span class="bool-val">false</span>, |
| pending: <span class="prelude-val">None</span>, |
| } |
| } |
| |
| <span class="doccomment">/// Enqueue a GOAWAY frame to be written. |
| /// |
| /// The connection is expected to continue to run until idle. |
| </span><span class="kw">pub fn </span>go_away(<span class="kw-2">&mut </span><span class="self">self</span>, f: frame::GoAway) { |
| <span class="kw">if let </span><span class="prelude-val">Some</span>(<span class="kw-2">ref </span>going_away) = <span class="self">self</span>.going_away { |
| <span class="macro">assert!</span>( |
| f.last_stream_id() <= going_away.last_processed_id, |
| <span class="string">"GOAWAY stream IDs shouldn't be higher; \ |
| last_processed_id = {:?}, f.last_stream_id() = {:?}"</span>, |
| going_away.last_processed_id, |
| f.last_stream_id(), |
| ); |
| } |
| |
| <span class="self">self</span>.going_away = <span class="prelude-val">Some</span>(GoingAway { |
| last_processed_id: f.last_stream_id(), |
| reason: f.reason(), |
| }); |
| <span class="self">self</span>.pending = <span class="prelude-val">Some</span>(f); |
| } |
| |
| <span class="kw">pub fn </span>go_away_now(<span class="kw-2">&mut </span><span class="self">self</span>, f: frame::GoAway) { |
| <span class="self">self</span>.close_now = <span class="bool-val">true</span>; |
| <span class="kw">if let </span><span class="prelude-val">Some</span>(<span class="kw-2">ref </span>going_away) = <span class="self">self</span>.going_away { |
| <span class="comment">// Prevent sending the same GOAWAY twice. |
| </span><span class="kw">if </span>going_away.last_processed_id == f.last_stream_id() && going_away.reason == f.reason() |
| { |
| <span class="kw">return</span>; |
| } |
| } |
| <span class="self">self</span>.go_away(f); |
| } |
| |
| <span class="kw">pub fn </span>go_away_from_user(<span class="kw-2">&mut </span><span class="self">self</span>, f: frame::GoAway) { |
| <span class="self">self</span>.is_user_initiated = <span class="bool-val">true</span>; |
| <span class="self">self</span>.go_away_now(f); |
| } |
| |
| <span class="doccomment">/// Return if a GOAWAY has ever been scheduled. |
| </span><span class="kw">pub fn </span>is_going_away(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| <span class="self">self</span>.going_away.is_some() |
| } |
| |
| <span class="kw">pub fn </span>is_user_initiated(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| <span class="self">self</span>.is_user_initiated |
| } |
| |
| <span class="doccomment">/// Returns the going away info, if any. |
| </span><span class="kw">pub fn </span>going_away(<span class="kw-2">&</span><span class="self">self</span>) -> <span class="prelude-ty">Option</span><<span class="kw-2">&</span>GoingAway> { |
| <span class="self">self</span>.going_away.as_ref() |
| } |
| |
| <span class="doccomment">/// Returns if the connection should close now, or wait until idle. |
| </span><span class="kw">pub fn </span>should_close_now(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| <span class="self">self</span>.pending.is_none() && <span class="self">self</span>.close_now |
| } |
| |
| <span class="doccomment">/// Returns if the connection should be closed when idle. |
| </span><span class="kw">pub fn </span>should_close_on_idle(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| !<span class="self">self</span>.close_now |
| && <span class="self">self |
| </span>.going_away |
| .as_ref() |
| .map(|g| g.last_processed_id != StreamId::MAX) |
| .unwrap_or(<span class="bool-val">false</span>) |
| } |
| |
| <span class="doccomment">/// Try to write a pending GOAWAY frame to the buffer. |
| /// |
| /// If a frame is written, the `Reason` of the GOAWAY is returned. |
| </span><span class="kw">pub fn </span>send_pending_go_away<T, B>( |
| <span class="kw-2">&mut </span><span class="self">self</span>, |
| cx: <span class="kw-2">&mut </span>Context, |
| dst: <span class="kw-2">&mut </span>Codec<T, B>, |
| ) -> Poll<<span class="prelude-ty">Option</span><io::Result<Reason>>> |
| <span class="kw">where |
| </span>T: AsyncWrite + Unpin, |
| B: Buf, |
| { |
| <span class="kw">if let </span><span class="prelude-val">Some</span>(frame) = <span class="self">self</span>.pending.take() { |
| <span class="kw">if </span>!dst.poll_ready(cx)<span class="question-mark">?</span>.is_ready() { |
| <span class="self">self</span>.pending = <span class="prelude-val">Some</span>(frame); |
| <span class="kw">return </span>Poll::Pending; |
| } |
| |
| <span class="kw">let </span>reason = frame.reason(); |
| dst.buffer(frame.into()).expect(<span class="string">"invalid GOAWAY frame"</span>); |
| |
| <span class="kw">return </span>Poll::Ready(<span class="prelude-val">Some</span>(<span class="prelude-val">Ok</span>(reason))); |
| } <span class="kw">else if </span><span class="self">self</span>.should_close_now() { |
| <span class="kw">return match </span><span class="self">self</span>.going_away().map(|going_away| going_away.reason) { |
| <span class="prelude-val">Some</span>(reason) => Poll::Ready(<span class="prelude-val">Some</span>(<span class="prelude-val">Ok</span>(reason))), |
| <span class="prelude-val">None </span>=> Poll::Ready(<span class="prelude-val">None</span>), |
| }; |
| } |
| |
| Poll::Ready(<span class="prelude-val">None</span>) |
| } |
| } |
| |
| <span class="kw">impl </span>GoingAway { |
| <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>reason(<span class="kw-2">&</span><span class="self">self</span>) -> Reason { |
| <span class="self">self</span>.reason |
| } |
| } |
| </code></pre></div> |
| </section></div></main><div id="rustdoc-vars" data-root-path="../../../" data-current-crate="h2" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0-nightly (5c8bff74b 2022-10-21)" ></div></body></html> |