| <!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/frame/util.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>util.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>std::fmt; |
| |
| <span class="kw">use </span><span class="kw">super</span>::Error; |
| <span class="kw">use </span>bytes::Bytes; |
| |
| <span class="doccomment">/// Strip padding from the given payload. |
| /// |
| /// It is assumed that the frame had the padded flag set. This means that the |
| /// first byte is the length of the padding with that many |
| /// 0 bytes expected to follow the actual payload. |
| /// |
| /// # Returns |
| /// |
| /// A slice of the given payload where the actual one is found and the length |
| /// of the padding. |
| /// |
| /// If the padded payload is invalid (e.g. the length of the padding is equal |
| /// to the total length), returns `None`. |
| </span><span class="kw">pub fn </span>strip_padding(payload: <span class="kw-2">&mut </span>Bytes) -> <span class="prelude-ty">Result</span><u8, Error> { |
| <span class="kw">let </span>payload_len = payload.len(); |
| <span class="kw">if </span>payload_len == <span class="number">0 </span>{ |
| <span class="comment">// If this is the case, the frame is invalid as no padding length can be |
| // extracted, even though the frame should be padded. |
| </span><span class="kw">return </span><span class="prelude-val">Err</span>(Error::TooMuchPadding); |
| } |
| |
| <span class="kw">let </span>pad_len = payload[<span class="number">0</span>] <span class="kw">as </span>usize; |
| |
| <span class="kw">if </span>pad_len >= payload_len { |
| <span class="comment">// This is invalid: the padding length MUST be less than the |
| // total frame size. |
| </span><span class="kw">return </span><span class="prelude-val">Err</span>(Error::TooMuchPadding); |
| } |
| |
| <span class="kw">let _ </span>= payload.split_to(<span class="number">1</span>); |
| <span class="kw">let _ </span>= payload.split_off(payload_len - pad_len - <span class="number">1</span>); |
| |
| <span class="prelude-val">Ok</span>(pad_len <span class="kw">as </span>u8) |
| } |
| |
| <span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">fn </span>debug_flags<<span class="lifetime">'a</span>, <span class="lifetime">'f</span>: <span class="lifetime">'a</span>>( |
| fmt: <span class="kw-2">&</span><span class="lifetime">'a </span><span class="kw-2">mut </span>fmt::Formatter<<span class="lifetime">'f</span>>, |
| bits: u8, |
| ) -> DebugFlags<<span class="lifetime">'a</span>, <span class="lifetime">'f</span>> { |
| <span class="kw">let </span>result = <span class="macro">write!</span>(fmt, <span class="string">"({:#x}"</span>, bits); |
| DebugFlags { |
| fmt, |
| result, |
| started: <span class="bool-val">false</span>, |
| } |
| } |
| |
| <span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">struct </span>DebugFlags<<span class="lifetime">'a</span>, <span class="lifetime">'f</span>: <span class="lifetime">'a</span>> { |
| fmt: <span class="kw-2">&</span><span class="lifetime">'a </span><span class="kw-2">mut </span>fmt::Formatter<<span class="lifetime">'f</span>>, |
| result: fmt::Result, |
| started: bool, |
| } |
| |
| <span class="kw">impl</span><<span class="lifetime">'a</span>, <span class="lifetime">'f</span>: <span class="lifetime">'a</span>> DebugFlags<<span class="lifetime">'a</span>, <span class="lifetime">'f</span>> { |
| <span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">fn </span>flag_if(<span class="kw-2">&mut </span><span class="self">self</span>, enabled: bool, name: <span class="kw-2">&</span>str) -> <span class="kw-2">&mut </span><span class="self">Self </span>{ |
| <span class="kw">if </span>enabled { |
| <span class="self">self</span>.result = <span class="self">self</span>.result.and_then(|()| { |
| <span class="kw">let </span>prefix = <span class="kw">if </span><span class="self">self</span>.started { |
| <span class="string">" | " |
| </span>} <span class="kw">else </span>{ |
| <span class="self">self</span>.started = <span class="bool-val">true</span>; |
| <span class="string">": " |
| </span>}; |
| |
| <span class="macro">write!</span>(<span class="self">self</span>.fmt, <span class="string">"{}{}"</span>, prefix, name) |
| }); |
| } |
| <span class="self">self |
| </span>} |
| |
| <span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">fn </span>finish(<span class="kw-2">&mut </span><span class="self">self</span>) -> fmt::Result { |
| <span class="self">self</span>.result.and_then(|()| <span class="macro">write!</span>(<span class="self">self</span>.fmt, <span class="string">")"</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> |
