| <!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/ring-0.16.20/src/endian.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>endian.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="../../ring/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="../../ring/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>core::num::Wrapping; |
| |
| <span class="doccomment">/// An `Encoding` of a type `T` can be converted to/from its byte |
| /// representation without any byte swapping or other computation. |
| /// |
| /// The `Self: Copy` constraint addresses `clippy::declare_interior_mutable_const`. |
| </span><span class="kw">pub trait </span>Encoding<T>: From<T> + Into<T> |
| <span class="kw">where |
| </span><span class="self">Self</span>: Copy, |
| { |
| <span class="kw">const </span>ZERO: <span class="self">Self</span>; |
| } |
| |
| <span class="doccomment">/// Allow access to a slice of of `Encoding<T>` as a slice of bytes. |
| </span><span class="kw">pub fn </span>as_byte_slice<E: Encoding<T>, T>(x: <span class="kw-2">&</span>[E]) -> <span class="kw-2">&</span>[u8] { |
| <span class="kw">unsafe </span>{ |
| core::slice::from_raw_parts(x.as_ptr() <span class="kw">as </span><span class="kw-2">*const </span>u8, x.len() * core::mem::size_of::<E>()) |
| } |
| } |
| |
| <span class="doccomment">/// Work around the inability to implement `AsRef` for arrays of `Encoding`s |
| /// due to the coherence rules. |
| </span><span class="kw">pub trait </span>ArrayEncoding<T> { |
| <span class="kw">fn </span>as_byte_array(<span class="kw-2">&</span><span class="self">self</span>) -> <span class="kw-2">&</span>T; |
| } |
| |
| <span class="doccomment">/// Work around the inability to implement `from` for arrays of `Encoding`s |
| /// due to the coherence rules. |
| </span><span class="kw">pub trait </span>FromByteArray<T> { |
| <span class="kw">fn </span>from_byte_array(a: <span class="kw-2">&</span>T) -> <span class="self">Self</span>; |
| } |
| |
| <span class="macro">macro_rules! </span>define_endian { |
| (<span class="macro-nonterminal">$endian</span>:ident) => { |
| <span class="attribute">#[repr(transparent)] |
| </span><span class="kw">pub struct </span><span class="macro-nonterminal">$endian</span><T>(T); |
| |
| <span class="kw">impl</span><T> <span class="macro-nonterminal">$endian</span><T> { |
| <span class="attribute">#[deprecated] |
| </span><span class="kw">pub fn </span>into_raw_value(<span class="self">self</span>) -> T { |
| <span class="self">self</span>.<span class="number">0 |
| </span>} |
| } |
| |
| <span class="kw">impl</span><T> Copy <span class="kw">for </span><span class="macro-nonterminal">$endian</span><T> <span class="kw">where </span>T: Copy {} |
| |
| <span class="kw">impl</span><T> Clone <span class="kw">for </span><span class="macro-nonterminal">$endian</span><T> |
| <span class="kw">where |
| </span>T: Clone, |
| { |
| <span class="kw">fn </span>clone(<span class="kw-2">&</span><span class="self">self</span>) -> <span class="self">Self </span>{ |
| <span class="self">Self</span>(<span class="self">self</span>.<span class="number">0</span>.clone()) |
| } |
| } |
| }; |
| } |
| |
| <span class="macro">macro_rules! </span>impl_from_byte_array { |
| (<span class="macro-nonterminal">$endian</span>:ident, <span class="macro-nonterminal">$base</span>:ident, <span class="macro-nonterminal">$elems</span>:expr) => { |
| <span class="kw">impl </span>FromByteArray<[u8; <span class="macro-nonterminal">$elems </span>* core::mem::size_of::<<span class="macro-nonterminal">$base</span>>()]> |
| <span class="kw">for </span>[<span class="macro-nonterminal">$endian</span><<span class="macro-nonterminal">$base</span>>; <span class="macro-nonterminal">$elems</span>] |
| { |
| <span class="kw">fn </span>from_byte_array(a: <span class="kw-2">&</span>[u8; <span class="macro-nonterminal">$elems </span>* core::mem::size_of::<<span class="macro-nonterminal">$base</span>>()]) -> <span class="self">Self </span>{ |
| <span class="kw">unsafe </span>{ core::mem::transmute_copy(a) } |
| } |
| } |
| }; |
| } |
| |
| <span class="macro">macro_rules! </span>impl_array_encoding { |
| (<span class="macro-nonterminal">$endian</span>:ident, <span class="macro-nonterminal">$base</span>:ident, <span class="macro-nonterminal">$elems</span>:expr) => { |
| <span class="kw">impl </span>ArrayEncoding<[u8; <span class="macro-nonterminal">$elems </span>* core::mem::size_of::<<span class="macro-nonterminal">$base</span>>()]> |
| <span class="kw">for </span>[<span class="macro-nonterminal">$endian</span><<span class="macro-nonterminal">$base</span>>; <span class="macro-nonterminal">$elems</span>] |
| { |
| <span class="kw">fn </span>as_byte_array(<span class="kw-2">&</span><span class="self">self</span>) -> <span class="kw-2">&</span>[u8; <span class="macro-nonterminal">$elems </span>* core::mem::size_of::<<span class="macro-nonterminal">$base</span>>()] { |
| <span class="comment">// TODO: When we can require Rust 1.47.0 or later we could avoid |
| // `as` and `unsafe` here using |
| // `as_byte_slice(self).try_into().unwrap()`. |
| </span><span class="kw">let </span>as_bytes_ptr = |
| <span class="self">self</span>.as_ptr() <span class="kw">as </span><span class="kw-2">*const </span>[u8; <span class="macro-nonterminal">$elems </span>* core::mem::size_of::<<span class="macro-nonterminal">$base</span>>()]; |
| <span class="kw">unsafe </span>{ <span class="kw-2">&*</span>as_bytes_ptr } |
| } |
| } |
| |
| <span class="macro">impl_from_byte_array!</span>(<span class="macro-nonterminal">$endian</span>, <span class="macro-nonterminal">$base</span>, <span class="macro-nonterminal">$elems</span>); |
| }; |
| } |
| |
| <span class="macro">macro_rules! </span>impl_endian { |
| (<span class="macro-nonterminal">$endian</span>:ident, <span class="macro-nonterminal">$base</span>:ident, <span class="macro-nonterminal">$to_endian</span>:ident, <span class="macro-nonterminal">$from_endian</span>:ident, <span class="macro-nonterminal">$size</span>:expr) => { |
| <span class="kw">impl </span>Encoding<<span class="macro-nonterminal">$base</span>> <span class="kw">for </span><span class="macro-nonterminal">$endian</span><<span class="macro-nonterminal">$base</span>> { |
| <span class="kw">const </span>ZERO: <span class="self">Self </span>= <span class="self">Self</span>(<span class="number">0</span>); |
| } |
| |
| <span class="kw">impl </span>From<[u8; <span class="macro-nonterminal">$size</span>]> <span class="kw">for </span><span class="macro-nonterminal">$endian</span><<span class="macro-nonterminal">$base</span>> { |
| <span class="attribute">#[inline] |
| </span><span class="kw">fn </span>from(bytes: [u8; <span class="macro-nonterminal">$size</span>]) -> <span class="self">Self </span>{ |
| <span class="self">Self</span>(<span class="macro-nonterminal">$base::from_ne_bytes</span>(bytes)) |
| } |
| } |
| |
| <span class="kw">impl </span>From<<span class="macro-nonterminal">$endian</span><<span class="macro-nonterminal">$base</span>>> <span class="kw">for </span>[u8; <span class="macro-nonterminal">$size</span>] { |
| <span class="attribute">#[inline] |
| </span><span class="kw">fn </span>from(encoded: <span class="macro-nonterminal">$endian</span><<span class="macro-nonterminal">$base</span>>) -> <span class="self">Self </span>{ |
| <span class="macro-nonterminal">$base::to_ne_bytes</span>(encoded.<span class="number">0</span>) |
| } |
| } |
| |
| <span class="kw">impl </span>From<<span class="macro-nonterminal">$base</span>> <span class="kw">for </span><span class="macro-nonterminal">$endian</span><<span class="macro-nonterminal">$base</span>> { |
| <span class="attribute">#[inline] |
| </span><span class="kw">fn </span>from(value: <span class="macro-nonterminal">$base</span>) -> <span class="self">Self </span>{ |
| <span class="self">Self</span>(<span class="macro-nonterminal">$base</span>::<span class="macro-nonterminal">$to_endian</span>(value)) |
| } |
| } |
| |
| <span class="kw">impl </span>From<Wrapping<<span class="macro-nonterminal">$base</span>>> <span class="kw">for </span><span class="macro-nonterminal">$endian</span><<span class="macro-nonterminal">$base</span>> { |
| <span class="attribute">#[inline] |
| </span><span class="kw">fn </span>from(Wrapping(value): Wrapping<<span class="macro-nonterminal">$base</span>>) -> <span class="self">Self </span>{ |
| <span class="self">Self</span>(<span class="macro-nonterminal">$base</span>::<span class="macro-nonterminal">$to_endian</span>(value)) |
| } |
| } |
| |
| <span class="kw">impl </span>From<<span class="macro-nonterminal">$endian</span><<span class="macro-nonterminal">$base</span>>> <span class="kw">for </span><span class="macro-nonterminal">$base </span>{ |
| <span class="attribute">#[inline] |
| </span><span class="kw">fn </span>from(<span class="macro-nonterminal">$endian</span>(value): <span class="macro-nonterminal">$endian</span><<span class="macro-nonterminal">$base</span>>) -> <span class="self">Self </span>{ |
| <span class="macro-nonterminal">$base</span>::<span class="macro-nonterminal">$from_endian</span>(value) |
| } |
| } |
| |
| <span class="macro">impl_array_encoding!</span>(<span class="macro-nonterminal">$endian</span>, <span class="macro-nonterminal">$base</span>, <span class="number">1</span>); |
| <span class="macro">impl_array_encoding!</span>(<span class="macro-nonterminal">$endian</span>, <span class="macro-nonterminal">$base</span>, <span class="number">2</span>); |
| <span class="macro">impl_array_encoding!</span>(<span class="macro-nonterminal">$endian</span>, <span class="macro-nonterminal">$base</span>, <span class="number">3</span>); |
| <span class="macro">impl_array_encoding!</span>(<span class="macro-nonterminal">$endian</span>, <span class="macro-nonterminal">$base</span>, <span class="number">4</span>); |
| <span class="macro">impl_array_encoding!</span>(<span class="macro-nonterminal">$endian</span>, <span class="macro-nonterminal">$base</span>, <span class="number">8</span>); |
| }; |
| } |
| |
| <span class="macro">define_endian!</span>(BigEndian); |
| <span class="macro">define_endian!</span>(LittleEndian); |
| <span class="macro">impl_endian!</span>(BigEndian, u32, to_be, from_be, <span class="number">4</span>); |
| <span class="macro">impl_endian!</span>(BigEndian, u64, to_be, from_be, <span class="number">8</span>); |
| <span class="macro">impl_endian!</span>(LittleEndian, u32, to_le, from_le, <span class="number">4</span>); |
| <span class="macro">impl_endian!</span>(LittleEndian, u64, to_le, from_le, <span class="number">8</span>); |
| |
| <span class="attribute">#[cfg(test)] |
| </span><span class="kw">mod </span>tests { |
| <span class="kw">use super</span>::<span class="kw-2">*</span>; |
| |
| <span class="attribute">#[test] |
| </span><span class="kw">fn </span>test_big_endian() { |
| <span class="kw">let </span>x = BigEndian::from(<span class="number">1u32</span>); |
| <span class="macro">assert_eq!</span>(u32::from(x), <span class="number">1</span>); |
| } |
| } |
| </code></pre></div> |
| </section></div></main><div id="rustdoc-vars" data-root-path="../../" data-current-crate="ring" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0-nightly (5c8bff74b 2022-10-21)" ></div></body></html> |
