| <!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/settings.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>settings.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> |
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| </pre><pre class="rust"><code><span class="kw">use </span><span class="kw">crate</span>::codec::UserError; |
| <span class="kw">use </span><span class="kw">crate</span>::error::Reason; |
| <span class="kw">use </span><span class="kw">crate</span>::frame; |
| <span class="kw">use </span><span class="kw">crate</span>::proto::<span class="kw-2">*</span>; |
| <span class="kw">use </span>std::task::{Context, Poll}; |
| |
| <span class="attribute">#[derive(Debug)] |
| </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">struct </span>Settings { |
| <span class="doccomment">/// Our local SETTINGS sync state with the remote. |
| </span>local: Local, |
| <span class="doccomment">/// Received SETTINGS frame pending processing. The ACK must be written to |
| /// the socket first then the settings applied **before** receiving any |
| /// further frames. |
| </span>remote: <span class="prelude-ty">Option</span><frame::Settings>, |
| } |
| |
| <span class="attribute">#[derive(Debug)] |
| </span><span class="kw">enum </span>Local { |
| <span class="doccomment">/// We want to send these SETTINGS to the remote when the socket is ready. |
| </span>ToSend(frame::Settings), |
| <span class="doccomment">/// We have sent these SETTINGS and are waiting for the remote to ACK |
| /// before we apply them. |
| </span>WaitingAck(frame::Settings), |
| <span class="doccomment">/// Our local settings are in sync with the remote. |
| </span>Synced, |
| } |
| |
| <span class="kw">impl </span>Settings { |
| <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>new(local: frame::Settings) -> <span class="self">Self </span>{ |
| Settings { |
| <span class="comment">// We assume the initial local SETTINGS were flushed during |
| // the handshake process. |
| </span>local: Local::WaitingAck(local), |
| remote: <span class="prelude-val">None</span>, |
| } |
| } |
| |
| <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>recv_settings<T, B, C, P>( |
| <span class="kw-2">&mut </span><span class="self">self</span>, |
| frame: frame::Settings, |
| codec: <span class="kw-2">&mut </span>Codec<T, B>, |
| streams: <span class="kw-2">&mut </span>Streams<C, P>, |
| ) -> <span class="prelude-ty">Result</span><(), Error> |
| <span class="kw">where |
| </span>T: AsyncWrite + Unpin, |
| B: Buf, |
| C: Buf, |
| P: Peer, |
| { |
| <span class="kw">if </span>frame.is_ack() { |
| <span class="kw">match </span><span class="kw-2">&</span><span class="self">self</span>.local { |
| Local::WaitingAck(local) => { |
| <span class="macro">tracing::debug!</span>(<span class="string">"received settings ACK; applying {:?}"</span>, local); |
| |
| <span class="kw">if let </span><span class="prelude-val">Some</span>(max) = local.max_frame_size() { |
| codec.set_max_recv_frame_size(max <span class="kw">as </span>usize); |
| } |
| |
| <span class="kw">if let </span><span class="prelude-val">Some</span>(max) = local.max_header_list_size() { |
| codec.set_max_recv_header_list_size(max <span class="kw">as </span>usize); |
| } |
| |
| streams.apply_local_settings(local)<span class="question-mark">?</span>; |
| <span class="self">self</span>.local = Local::Synced; |
| <span class="prelude-val">Ok</span>(()) |
| } |
| Local::ToSend(..) | Local::Synced => { |
| <span class="comment">// We haven't sent any SETTINGS frames to be ACKed, so |
| // this is very bizarre! Remote is either buggy or malicious. |
| </span><span class="macro">proto_err!</span>(conn: <span class="string">"received unexpected settings ack"</span>); |
| <span class="prelude-val">Err</span>(Error::library_go_away(Reason::PROTOCOL_ERROR)) |
| } |
| } |
| } <span class="kw">else </span>{ |
| <span class="comment">// We always ACK before reading more frames, so `remote` should |
| // always be none! |
| </span><span class="macro">assert!</span>(<span class="self">self</span>.remote.is_none()); |
| <span class="self">self</span>.remote = <span class="prelude-val">Some</span>(frame); |
| <span class="prelude-val">Ok</span>(()) |
| } |
| } |
| |
| <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>send_settings(<span class="kw-2">&mut </span><span class="self">self</span>, frame: frame::Settings) -> <span class="prelude-ty">Result</span><(), UserError> { |
| <span class="macro">assert!</span>(!frame.is_ack()); |
| <span class="kw">match </span><span class="kw-2">&</span><span class="self">self</span>.local { |
| Local::ToSend(..) | Local::WaitingAck(..) => <span class="prelude-val">Err</span>(UserError::SendSettingsWhilePending), |
| Local::Synced => { |
| <span class="macro">tracing::trace!</span>(<span class="string">"queue to send local settings: {:?}"</span>, frame); |
| <span class="self">self</span>.local = Local::ToSend(frame); |
| <span class="prelude-val">Ok</span>(()) |
| } |
| } |
| } |
| |
| <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>poll_send<T, B, C, P>( |
| <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>, |
| streams: <span class="kw-2">&mut </span>Streams<C, P>, |
| ) -> Poll<<span class="prelude-ty">Result</span><(), Error>> |
| <span class="kw">where |
| </span>T: AsyncWrite + Unpin, |
| B: Buf, |
| C: Buf, |
| P: Peer, |
| { |
| <span class="kw">if let </span><span class="prelude-val">Some</span>(settings) = <span class="kw-2">&</span><span class="self">self</span>.remote { |
| <span class="kw">if </span>!dst.poll_ready(cx)<span class="question-mark">?</span>.is_ready() { |
| <span class="kw">return </span>Poll::Pending; |
| } |
| |
| <span class="comment">// Create an ACK settings frame |
| </span><span class="kw">let </span>frame = frame::Settings::ack(); |
| |
| <span class="comment">// Buffer the settings frame |
| </span>dst.buffer(frame.into()).expect(<span class="string">"invalid settings frame"</span>); |
| |
| <span class="macro">tracing::trace!</span>(<span class="string">"ACK sent; applying settings"</span>); |
| |
| streams.apply_remote_settings(settings)<span class="question-mark">?</span>; |
| |
| <span class="kw">if let </span><span class="prelude-val">Some</span>(val) = settings.header_table_size() { |
| dst.set_send_header_table_size(val <span class="kw">as </span>usize); |
| } |
| |
| <span class="kw">if let </span><span class="prelude-val">Some</span>(val) = settings.max_frame_size() { |
| dst.set_max_send_frame_size(val <span class="kw">as </span>usize); |
| } |
| } |
| |
| <span class="self">self</span>.remote = <span class="prelude-val">None</span>; |
| |
| <span class="kw">match </span><span class="kw-2">&</span><span class="self">self</span>.local { |
| Local::ToSend(settings) => { |
| <span class="kw">if </span>!dst.poll_ready(cx)<span class="question-mark">?</span>.is_ready() { |
| <span class="kw">return </span>Poll::Pending; |
| } |
| |
| <span class="comment">// Buffer the settings frame |
| </span>dst.buffer(settings.clone().into()) |
| .expect(<span class="string">"invalid settings frame"</span>); |
| <span class="macro">tracing::trace!</span>(<span class="string">"local settings sent; waiting for ack: {:?}"</span>, settings); |
| |
| <span class="self">self</span>.local = Local::WaitingAck(settings.clone()); |
| } |
| Local::WaitingAck(..) | Local::Synced => {} |
| } |
| |
| Poll::Ready(<span class="prelude-val">Ok</span>(())) |
| } |
| } |
| </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> |
