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diff --git a/rust/theBook/chapter-2-guessing-game/guessing_game/target/doc/src/rand/rngs/adapter/mod.rs.html b/rust/theBook/chapter-2-guessing-game/guessing_game/target/doc/src/rand/rngs/adapter/mod.rs.html new file mode 100644 index 0000000..a272f93 --- /dev/null +++ b/rust/theBook/chapter-2-guessing-game/guessing_game/target/doc/src/rand/rngs/adapter/mod.rs.html @@ -0,0 +1,35 @@ +<!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 `/home/pico/.local/share/cargo/registry/src/github.com-1ecc6299db9ec823/rand-0.8.5/src/rngs/adapter/mod.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>mod.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="icon" href="https://www.rust-lang.org/favicon.ico"></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"></nav><main><div class="width-limiter"><nav class="sub"><a class="sub-logo-container" href="../../../../rand/index.html"> + <img src="https://www.rust-lang.org/logos/rust-logo-128x128-blk.png" alt="logo"></a><form class="search-form"><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></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> +</pre><pre class="rust"><code><span class="comment">// Copyright 2018 Developers of the Rand project. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +</span><span class="doccomment">//! Wrappers / adapters forming RNGs + +</span><span class="kw">mod </span>read; +<span class="kw">mod </span>reseeding; + +<span class="attribute">#[allow(deprecated)] +</span><span class="kw">pub use </span><span class="self">self</span>::read::{ReadError, ReadRng}; +<span class="kw">pub use </span><span class="self">self</span>::reseeding::ReseedingRng; +</code></pre></div> +</section></div></main><div id="rustdoc-vars" data-root-path="../../../../" data-current-crate="rand" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0 (69f9c33d7 2022-12-12) (Arch Linux rust 1:1.66.0-1)" ></div></body></html>
\ No newline at end of file diff --git a/rust/theBook/chapter-2-guessing-game/guessing_game/target/doc/src/rand/rngs/adapter/read.rs.html b/rust/theBook/chapter-2-guessing-game/guessing_game/target/doc/src/rand/rngs/adapter/read.rs.html new file mode 100644 index 0000000..d16c0fb --- /dev/null +++ b/rust/theBook/chapter-2-guessing-game/guessing_game/target/doc/src/rand/rngs/adapter/read.rs.html @@ -0,0 +1,303 @@ +<!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 `/home/pico/.local/share/cargo/registry/src/github.com-1ecc6299db9ec823/rand-0.8.5/src/rngs/adapter/read.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>read.rs - source</title><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../../SourceSerif4-Regular.ttf.woff2"><link rel="preload" as="font" 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src="../../../../source-files.js"></script><script defer src="../../../../main.js"></script><noscript><link rel="stylesheet" href="../../../../noscript.css"></noscript><link rel="icon" href="https://www.rust-lang.org/favicon.ico"></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"></nav><main><div class="width-limiter"><nav class="sub"><a class="sub-logo-container" href="../../../../rand/index.html"> + <img src="https://www.rust-lang.org/logos/rust-logo-128x128-blk.png" alt="logo"></a><form class="search-form"><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></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> +</pre><pre class="rust"><code><span class="comment">// Copyright 2018 Developers of the Rand project. +// Copyright 2013 The Rust Project Developers. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +</span><span class="doccomment">//! A wrapper around any Read to treat it as an RNG. + +</span><span class="attribute">#![allow(deprecated)] + +</span><span class="kw">use </span>std::fmt; +<span class="kw">use </span>std::io::Read; + +<span class="kw">use </span>rand_core::{impls, Error, RngCore}; + + +<span class="doccomment">/// An RNG that reads random bytes straight from any type supporting +/// [`std::io::Read`], for example files. +/// +/// This will work best with an infinite reader, but that is not required. +/// +/// This can be used with `/dev/urandom` on Unix but it is recommended to use +/// [`OsRng`] instead. +/// +/// # Panics +/// +/// `ReadRng` uses [`std::io::Read::read_exact`], which retries on interrupts. +/// All other errors from the underlying reader, including when it does not +/// have enough data, will only be reported through [`try_fill_bytes`]. +/// The other [`RngCore`] methods will panic in case of an error. +/// +/// [`OsRng`]: crate::rngs::OsRng +/// [`try_fill_bytes`]: RngCore::try_fill_bytes +</span><span class="attribute">#[derive(Debug)] +#[deprecated(since=<span class="string">"0.8.4"</span>, note=<span class="string">"removal due to lack of usage"</span>)] +</span><span class="kw">pub struct </span>ReadRng<R> { + reader: R, +} + +<span class="kw">impl</span><R: Read> ReadRng<R> { + <span class="doccomment">/// Create a new `ReadRng` from a `Read`. + </span><span class="kw">pub fn </span>new(r: R) -> ReadRng<R> { + ReadRng { reader: r } + } +} + +<span class="kw">impl</span><R: Read> RngCore <span class="kw">for </span>ReadRng<R> { + <span class="kw">fn </span>next_u32(<span class="kw-2">&mut </span><span class="self">self</span>) -> u32 { + impls::next_u32_via_fill(<span class="self">self</span>) + } + + <span class="kw">fn </span>next_u64(<span class="kw-2">&mut </span><span class="self">self</span>) -> u64 { + impls::next_u64_via_fill(<span class="self">self</span>) + } + + <span class="kw">fn </span>fill_bytes(<span class="kw-2">&mut </span><span class="self">self</span>, dest: <span class="kw-2">&mut </span>[u8]) { + <span class="self">self</span>.try_fill_bytes(dest).unwrap_or_else(|err| { + <span class="macro">panic!</span>( + <span class="string">"reading random bytes from Read implementation failed; error: {}"</span>, + err + ) + }); + } + + <span class="kw">fn </span>try_fill_bytes(<span class="kw-2">&mut </span><span class="self">self</span>, dest: <span class="kw-2">&mut </span>[u8]) -> <span class="prelude-ty">Result</span><(), Error> { + <span class="kw">if </span>dest.is_empty() { + <span class="kw">return </span><span class="prelude-val">Ok</span>(()); + } + <span class="comment">// Use `std::io::read_exact`, which retries on `ErrorKind::Interrupted`. + </span><span class="self">self</span>.reader + .read_exact(dest) + .map_err(|e| Error::new(ReadError(e))) + } +} + +<span class="doccomment">/// `ReadRng` error type +</span><span class="attribute">#[derive(Debug)] +#[deprecated(since=<span class="string">"0.8.4"</span>)] +</span><span class="kw">pub struct </span>ReadError(std::io::Error); + +<span class="kw">impl </span>fmt::Display <span class="kw">for </span>ReadError { + <span class="kw">fn </span>fmt(<span class="kw-2">&</span><span class="self">self</span>, f: <span class="kw-2">&mut </span>fmt::Formatter) -> fmt::Result { + <span class="macro">write!</span>(f, <span class="string">"ReadError: {}"</span>, <span class="self">self</span>.<span class="number">0</span>) + } +} + +<span class="kw">impl </span>std::error::Error <span class="kw">for </span>ReadError { + <span class="kw">fn </span>source(<span class="kw-2">&</span><span class="self">self</span>) -> <span class="prelude-ty">Option</span><<span class="kw-2">&</span>(<span class="kw">dyn </span>std::error::Error + <span class="lifetime">'static</span>)> { + <span class="prelude-val">Some</span>(<span class="kw-2">&</span><span class="self">self</span>.<span class="number">0</span>) + } +} + + +<span class="attribute">#[cfg(test)] +</span><span class="kw">mod </span>test { + <span class="kw">use </span>std::println; + + <span class="kw">use </span><span class="kw">super</span>::ReadRng; + <span class="kw">use </span><span class="kw">crate</span>::RngCore; + + <span class="attribute">#[test] + </span><span class="kw">fn </span>test_reader_rng_u64() { + <span class="comment">// transmute from the target to avoid endianness concerns. + </span><span class="attribute">#[rustfmt::skip] + </span><span class="kw">let </span>v = [<span class="number">0u8</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">1</span>, + <span class="number">0</span>, <span class="number">4</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">3</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">2</span>, + <span class="number">5</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>]; + <span class="kw">let </span><span class="kw-2">mut </span>rng = ReadRng::new(<span class="kw-2">&</span>v[..]); + + <span class="macro">assert_eq!</span>(rng.next_u64(), <span class="number">1 </span><< <span class="number">56</span>); + <span class="macro">assert_eq!</span>(rng.next_u64(), (<span class="number">2 </span><< <span class="number">56</span>) + (<span class="number">3 </span><< <span class="number">32</span>) + (<span class="number">4 </span><< <span class="number">8</span>)); + <span class="macro">assert_eq!</span>(rng.next_u64(), <span class="number">5</span>); + } + + <span class="attribute">#[test] + </span><span class="kw">fn </span>test_reader_rng_u32() { + <span class="kw">let </span>v = [<span class="number">0u8</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">1</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">2</span>, <span class="number">0</span>, <span class="number">3</span>, <span class="number">0</span>, <span class="number">0</span>, <span class="number">0</span>]; + <span class="kw">let </span><span class="kw-2">mut </span>rng = ReadRng::new(<span class="kw-2">&</span>v[..]); + + <span class="macro">assert_eq!</span>(rng.next_u32(), <span class="number">1 </span><< <span class="number">24</span>); + <span class="macro">assert_eq!</span>(rng.next_u32(), <span class="number">2 </span><< <span class="number">16</span>); + <span class="macro">assert_eq!</span>(rng.next_u32(), <span class="number">3</span>); + } + + <span class="attribute">#[test] + </span><span class="kw">fn </span>test_reader_rng_fill_bytes() { + <span class="kw">let </span>v = [<span class="number">1u8</span>, <span class="number">2</span>, <span class="number">3</span>, <span class="number">4</span>, <span class="number">5</span>, <span class="number">6</span>, <span class="number">7</span>, <span class="number">8</span>]; + <span class="kw">let </span><span class="kw-2">mut </span>w = [<span class="number">0u8</span>; <span class="number">8</span>]; + + <span class="kw">let </span><span class="kw-2">mut </span>rng = ReadRng::new(<span class="kw-2">&</span>v[..]); + rng.fill_bytes(<span class="kw-2">&mut </span>w); + + <span class="macro">assert!</span>(v == w); + } + + <span class="attribute">#[test] + </span><span class="kw">fn </span>test_reader_rng_insufficient_bytes() { + <span class="kw">let </span>v = [<span class="number">1u8</span>, <span class="number">2</span>, <span class="number">3</span>, <span class="number">4</span>, <span class="number">5</span>, <span class="number">6</span>, <span class="number">7</span>, <span class="number">8</span>]; + <span class="kw">let </span><span class="kw-2">mut </span>w = [<span class="number">0u8</span>; <span class="number">9</span>]; + + <span class="kw">let </span><span class="kw-2">mut </span>rng = ReadRng::new(<span class="kw-2">&</span>v[..]); + + <span class="kw">let </span>result = rng.try_fill_bytes(<span class="kw-2">&mut </span>w); + <span class="macro">assert!</span>(result.is_err()); + <span class="macro">println!</span>(<span class="string">"Error: {}"</span>, result.unwrap_err()); + } +} +</code></pre></div> +</section></div></main><div id="rustdoc-vars" data-root-path="../../../../" data-current-crate="rand" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0 (69f9c33d7 2022-12-12) (Arch Linux rust 1:1.66.0-1)" ></div></body></html>
\ No newline at end of file diff --git a/rust/theBook/chapter-2-guessing-game/guessing_game/target/doc/src/rand/rngs/adapter/reseeding.rs.html b/rust/theBook/chapter-2-guessing-game/guessing_game/target/doc/src/rand/rngs/adapter/reseeding.rs.html new file mode 100644 index 0000000..93f4eaf --- /dev/null +++ b/rust/theBook/chapter-2-guessing-game/guessing_game/target/doc/src/rand/rngs/adapter/reseeding.rs.html @@ -0,0 +1,775 @@ +<!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 `/home/pico/.local/share/cargo/registry/src/github.com-1ecc6299db9ec823/rand-0.8.5/src/rngs/adapter/reseeding.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>reseeding.rs - source</title><link rel="preload" as="font" type="font/woff2" crossorigin href="../../../../SourceSerif4-Regular.ttf.woff2"><link rel="preload" 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title="settings"><img width="22" height="22" alt="Change settings" src="../../../../wheel.svg"></a></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> 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+<span id="371">371</span> +<span id="372">372</span> +<span id="373">373</span> +<span id="374">374</span> +<span id="375">375</span> +<span id="376">376</span> +<span id="377">377</span> +<span id="378">378</span> +<span id="379">379</span> +<span id="380">380</span> +<span id="381">381</span> +<span id="382">382</span> +<span id="383">383</span> +<span id="384">384</span> +<span id="385">385</span> +<span id="386">386</span> +</pre><pre class="rust"><code><span class="comment">// Copyright 2018 Developers of the Rand project. +// Copyright 2013 The Rust Project Developers. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +</span><span class="doccomment">//! A wrapper around another PRNG that reseeds it after it +//! generates a certain number of random bytes. + +</span><span class="kw">use </span>core::mem::size_of; + +<span class="kw">use </span>rand_core::block::{BlockRng, BlockRngCore}; +<span class="kw">use </span>rand_core::{CryptoRng, Error, RngCore, SeedableRng}; + +<span class="doccomment">/// A wrapper around any PRNG that implements [`BlockRngCore`], that adds the +/// ability to reseed it. +/// +/// `ReseedingRng` reseeds the underlying PRNG in the following cases: +/// +/// - On a manual call to [`reseed()`]. +/// - After `clone()`, the clone will be reseeded on first use. +/// - When a process is forked on UNIX, the RNGs in both the parent and child +/// processes will be reseeded just before the next call to +/// [`BlockRngCore::generate`], i.e. "soon". For ChaCha and Hc128 this is a +/// maximum of fifteen `u32` values before reseeding. +/// - After the PRNG has generated a configurable number of random bytes. +/// +/// # When should reseeding after a fixed number of generated bytes be used? +/// +/// Reseeding after a fixed number of generated bytes is never strictly +/// *necessary*. Cryptographic PRNGs don't have a limited number of bytes they +/// can output, or at least not a limit reachable in any practical way. There is +/// no such thing as 'running out of entropy'. +/// +/// Occasionally reseeding can be seen as some form of 'security in depth'. Even +/// if in the future a cryptographic weakness is found in the CSPRNG being used, +/// or a flaw in the implementation, occasionally reseeding should make +/// exploiting it much more difficult or even impossible. +/// +/// Use [`ReseedingRng::new`] with a `threshold` of `0` to disable reseeding +/// after a fixed number of generated bytes. +/// +/// # Limitations +/// +/// It is recommended that a `ReseedingRng` (including `ThreadRng`) not be used +/// from a fork handler. +/// Use `OsRng` or `getrandom`, or defer your use of the RNG until later. +/// +/// # Error handling +/// +/// Although unlikely, reseeding the wrapped PRNG can fail. `ReseedingRng` will +/// never panic but try to handle the error intelligently through some +/// combination of retrying and delaying reseeding until later. +/// If handling the source error fails `ReseedingRng` will continue generating +/// data from the wrapped PRNG without reseeding. +/// +/// Manually calling [`reseed()`] will not have this retry or delay logic, but +/// reports the error. +/// +/// # Example +/// +/// ``` +/// use rand::prelude::*; +/// use rand_chacha::ChaCha20Core; // Internal part of ChaChaRng that +/// // implements BlockRngCore +/// use rand::rngs::OsRng; +/// use rand::rngs::adapter::ReseedingRng; +/// +/// let prng = ChaCha20Core::from_entropy(); +/// let mut reseeding_rng = ReseedingRng::new(prng, 0, OsRng); +/// +/// println!("{}", reseeding_rng.gen::<u64>()); +/// +/// let mut cloned_rng = reseeding_rng.clone(); +/// assert!(reseeding_rng.gen::<u64>() != cloned_rng.gen::<u64>()); +/// ``` +/// +/// [`BlockRngCore`]: rand_core::block::BlockRngCore +/// [`ReseedingRng::new`]: ReseedingRng::new +/// [`reseed()`]: ReseedingRng::reseed +</span><span class="attribute">#[derive(Debug)] +</span><span class="kw">pub struct </span>ReseedingRng<R, Rsdr>(BlockRng<ReseedingCore<R, Rsdr>>) +<span class="kw">where + </span>R: BlockRngCore + SeedableRng, + Rsdr: RngCore; + +<span class="kw">impl</span><R, Rsdr> ReseedingRng<R, Rsdr> +<span class="kw">where + </span>R: BlockRngCore + SeedableRng, + Rsdr: RngCore, +{ + <span class="doccomment">/// Create a new `ReseedingRng` from an existing PRNG, combined with a RNG + /// to use as reseeder. + /// + /// `threshold` sets the number of generated bytes after which to reseed the + /// PRNG. Set it to zero to never reseed based on the number of generated + /// values. + </span><span class="kw">pub fn </span>new(rng: R, threshold: u64, reseeder: Rsdr) -> <span class="self">Self </span>{ + ReseedingRng(BlockRng::new(ReseedingCore::new(rng, threshold, reseeder))) + } + + <span class="doccomment">/// Reseed the internal PRNG. + </span><span class="kw">pub fn </span>reseed(<span class="kw-2">&mut </span><span class="self">self</span>) -> <span class="prelude-ty">Result</span><(), Error> { + <span class="self">self</span>.<span class="number">0</span>.core.reseed() + } +} + +<span class="comment">// TODO: this should be implemented for any type where the inner type +// implements RngCore, but we can't specify that because ReseedingCore is private +</span><span class="kw">impl</span><R, Rsdr: RngCore> RngCore <span class="kw">for </span>ReseedingRng<R, Rsdr> +<span class="kw">where + </span>R: BlockRngCore<Item = u32> + SeedableRng, + <R <span class="kw">as </span>BlockRngCore>::Results: AsRef<[u32]> + AsMut<[u32]>, +{ + <span class="attribute">#[inline(always)] + </span><span class="kw">fn </span>next_u32(<span class="kw-2">&mut </span><span class="self">self</span>) -> u32 { + <span class="self">self</span>.<span class="number">0</span>.next_u32() + } + + <span class="attribute">#[inline(always)] + </span><span class="kw">fn </span>next_u64(<span class="kw-2">&mut </span><span class="self">self</span>) -> u64 { + <span class="self">self</span>.<span class="number">0</span>.next_u64() + } + + <span class="kw">fn </span>fill_bytes(<span class="kw-2">&mut </span><span class="self">self</span>, dest: <span class="kw-2">&mut </span>[u8]) { + <span class="self">self</span>.<span class="number">0</span>.fill_bytes(dest) + } + + <span class="kw">fn </span>try_fill_bytes(<span class="kw-2">&mut </span><span class="self">self</span>, dest: <span class="kw-2">&mut </span>[u8]) -> <span class="prelude-ty">Result</span><(), Error> { + <span class="self">self</span>.<span class="number">0</span>.try_fill_bytes(dest) + } +} + +<span class="kw">impl</span><R, Rsdr> Clone <span class="kw">for </span>ReseedingRng<R, Rsdr> +<span class="kw">where + </span>R: BlockRngCore + SeedableRng + Clone, + Rsdr: RngCore + Clone, +{ + <span class="kw">fn </span>clone(<span class="kw-2">&</span><span class="self">self</span>) -> ReseedingRng<R, Rsdr> { + <span class="comment">// Recreating `BlockRng` seems easier than cloning it and resetting + // the index. + </span>ReseedingRng(BlockRng::new(<span class="self">self</span>.<span class="number">0</span>.core.clone())) + } +} + +<span class="kw">impl</span><R, Rsdr> CryptoRng <span class="kw">for </span>ReseedingRng<R, Rsdr> +<span class="kw">where + </span>R: BlockRngCore + SeedableRng + CryptoRng, + Rsdr: RngCore + CryptoRng, +{ +} + +<span class="attribute">#[derive(Debug)] +</span><span class="kw">struct </span>ReseedingCore<R, Rsdr> { + inner: R, + reseeder: Rsdr, + threshold: i64, + bytes_until_reseed: i64, + fork_counter: usize, +} + +<span class="kw">impl</span><R, Rsdr> BlockRngCore <span class="kw">for </span>ReseedingCore<R, Rsdr> +<span class="kw">where + </span>R: BlockRngCore + SeedableRng, + Rsdr: RngCore, +{ + <span class="kw">type </span>Item = <R <span class="kw">as </span>BlockRngCore>::Item; + <span class="kw">type </span>Results = <R <span class="kw">as </span>BlockRngCore>::Results; + + <span class="kw">fn </span>generate(<span class="kw-2">&mut </span><span class="self">self</span>, results: <span class="kw-2">&mut </span><span class="self">Self</span>::Results) { + <span class="kw">let </span>global_fork_counter = fork::get_fork_counter(); + <span class="kw">if </span><span class="self">self</span>.bytes_until_reseed <= <span class="number">0 </span>|| <span class="self">self</span>.is_forked(global_fork_counter) { + <span class="comment">// We get better performance by not calling only `reseed` here + // and continuing with the rest of the function, but by directly + // returning from a non-inlined function. + </span><span class="kw">return </span><span class="self">self</span>.reseed_and_generate(results, global_fork_counter); + } + <span class="kw">let </span>num_bytes = results.as_ref().len() * size_of::<<span class="self">Self</span>::Item>(); + <span class="self">self</span>.bytes_until_reseed -= num_bytes <span class="kw">as </span>i64; + <span class="self">self</span>.inner.generate(results); + } +} + +<span class="kw">impl</span><R, Rsdr> ReseedingCore<R, Rsdr> +<span class="kw">where + </span>R: BlockRngCore + SeedableRng, + Rsdr: RngCore, +{ + <span class="doccomment">/// Create a new `ReseedingCore`. + </span><span class="kw">fn </span>new(rng: R, threshold: u64, reseeder: Rsdr) -> <span class="self">Self </span>{ + <span class="kw">use </span>::core::i64::MAX; + fork::register_fork_handler(); + + <span class="comment">// Because generating more values than `i64::MAX` takes centuries on + // current hardware, we just clamp to that value. + // Also we set a threshold of 0, which indicates no limit, to that + // value. + </span><span class="kw">let </span>threshold = <span class="kw">if </span>threshold == <span class="number">0 </span>{ + MAX + } <span class="kw">else if </span>threshold <= MAX <span class="kw">as </span>u64 { + threshold <span class="kw">as </span>i64 + } <span class="kw">else </span>{ + MAX + }; + + ReseedingCore { + inner: rng, + reseeder, + threshold: threshold <span class="kw">as </span>i64, + bytes_until_reseed: threshold <span class="kw">as </span>i64, + fork_counter: <span class="number">0</span>, + } + } + + <span class="doccomment">/// Reseed the internal PRNG. + </span><span class="kw">fn </span>reseed(<span class="kw-2">&mut </span><span class="self">self</span>) -> <span class="prelude-ty">Result</span><(), Error> { + R::from_rng(<span class="kw-2">&mut </span><span class="self">self</span>.reseeder).map(|result| { + <span class="self">self</span>.bytes_until_reseed = <span class="self">self</span>.threshold; + <span class="self">self</span>.inner = result + }) + } + + <span class="kw">fn </span>is_forked(<span class="kw-2">&</span><span class="self">self</span>, global_fork_counter: usize) -> bool { + <span class="comment">// In theory, on 32-bit platforms, it is possible for + // `global_fork_counter` to wrap around after ~4e9 forks. + // + // This check will detect a fork in the normal case where + // `fork_counter < global_fork_counter`, and also when the difference + // between both is greater than `isize::MAX` (wrapped around). + // + // It will still fail to detect a fork if there have been more than + // `isize::MAX` forks, without any reseed in between. Seems unlikely + // enough. + </span>(<span class="self">self</span>.fork_counter.wrapping_sub(global_fork_counter) <span class="kw">as </span>isize) < <span class="number">0 + </span>} + + <span class="attribute">#[inline(never)] + </span><span class="kw">fn </span>reseed_and_generate( + <span class="kw-2">&mut </span><span class="self">self</span>, results: <span class="kw-2">&mut </span><<span class="self">Self </span><span class="kw">as </span>BlockRngCore>::Results, global_fork_counter: usize, + ) { + <span class="attribute">#![allow(clippy::if_same_then_else)] </span><span class="comment">// false positive + </span><span class="kw">if </span><span class="self">self</span>.is_forked(global_fork_counter) { + <span class="macro">info!</span>(<span class="string">"Fork detected, reseeding RNG"</span>); + } <span class="kw">else </span>{ + <span class="macro">trace!</span>(<span class="string">"Reseeding RNG (periodic reseed)"</span>); + } + + <span class="kw">let </span>num_bytes = results.as_ref().len() * size_of::<<R <span class="kw">as </span>BlockRngCore>::Item>(); + + <span class="kw">if let </span><span class="prelude-val">Err</span>(e) = <span class="self">self</span>.reseed() { + <span class="macro">warn!</span>(<span class="string">"Reseeding RNG failed: {}"</span>, e); + <span class="kw">let _ </span>= e; + } + <span class="self">self</span>.fork_counter = global_fork_counter; + + <span class="self">self</span>.bytes_until_reseed = <span class="self">self</span>.threshold - num_bytes <span class="kw">as </span>i64; + <span class="self">self</span>.inner.generate(results); + } +} + +<span class="kw">impl</span><R, Rsdr> Clone <span class="kw">for </span>ReseedingCore<R, Rsdr> +<span class="kw">where + </span>R: BlockRngCore + SeedableRng + Clone, + Rsdr: RngCore + Clone, +{ + <span class="kw">fn </span>clone(<span class="kw-2">&</span><span class="self">self</span>) -> ReseedingCore<R, Rsdr> { + ReseedingCore { + inner: <span class="self">self</span>.inner.clone(), + reseeder: <span class="self">self</span>.reseeder.clone(), + threshold: <span class="self">self</span>.threshold, + bytes_until_reseed: <span class="number">0</span>, <span class="comment">// reseed clone on first use + </span>fork_counter: <span class="self">self</span>.fork_counter, + } + } +} + +<span class="kw">impl</span><R, Rsdr> CryptoRng <span class="kw">for </span>ReseedingCore<R, Rsdr> +<span class="kw">where + </span>R: BlockRngCore + SeedableRng + CryptoRng, + Rsdr: RngCore + CryptoRng, +{ +} + + +<span class="attribute">#[cfg(all(unix, not(target_os = <span class="string">"emscripten"</span>)))] +</span><span class="kw">mod </span>fork { + <span class="kw">use </span>core::sync::atomic::{AtomicUsize, Ordering}; + <span class="kw">use </span>std::sync::Once; + + <span class="comment">// Fork protection + // + // We implement fork protection on Unix using `pthread_atfork`. + // When the process is forked, we increment `RESEEDING_RNG_FORK_COUNTER`. + // Every `ReseedingRng` stores the last known value of the static in + // `fork_counter`. If the cached `fork_counter` is less than + // `RESEEDING_RNG_FORK_COUNTER`, it is time to reseed this RNG. + // + // If reseeding fails, we don't deal with this by setting a delay, but just + // don't update `fork_counter`, so a reseed is attempted as soon as + // possible. + + </span><span class="kw">static </span>RESEEDING_RNG_FORK_COUNTER: AtomicUsize = AtomicUsize::new(<span class="number">0</span>); + + <span class="kw">pub fn </span>get_fork_counter() -> usize { + RESEEDING_RNG_FORK_COUNTER.load(Ordering::Relaxed) + } + + <span class="kw">extern </span><span class="string">"C" </span><span class="kw">fn </span>fork_handler() { + <span class="comment">// Note: fetch_add is defined to wrap on overflow + // (which is what we want). + </span>RESEEDING_RNG_FORK_COUNTER.fetch_add(<span class="number">1</span>, Ordering::Relaxed); + } + + <span class="kw">pub fn </span>register_fork_handler() { + <span class="kw">static </span>REGISTER: Once = Once::new(); + REGISTER.call_once(|| { + <span class="comment">// Bump the counter before and after forking (see #1169): + </span><span class="kw">let </span>ret = <span class="kw">unsafe </span>{ libc::pthread_atfork( + <span class="prelude-val">Some</span>(fork_handler), + <span class="prelude-val">Some</span>(fork_handler), + <span class="prelude-val">Some</span>(fork_handler), + ) }; + <span class="kw">if </span>ret != <span class="number">0 </span>{ + <span class="macro">panic!</span>(<span class="string">"libc::pthread_atfork failed with code {}"</span>, ret); + } + }); + } +} + +<span class="attribute">#[cfg(not(all(unix, not(target_os = <span class="string">"emscripten"</span>))))] +</span><span class="kw">mod </span>fork { + <span class="kw">pub fn </span>get_fork_counter() -> usize { + <span class="number">0 + </span>} + <span class="kw">pub fn </span>register_fork_handler() {} +} + + +<span class="attribute">#[cfg(feature = <span class="string">"std_rng"</span>)] +#[cfg(test)] +</span><span class="kw">mod </span>test { + <span class="kw">use </span><span class="kw">super</span>::ReseedingRng; + <span class="kw">use </span><span class="kw">crate</span>::rngs::mock::StepRng; + <span class="kw">use </span><span class="kw">crate</span>::rngs::std::Core; + <span class="kw">use crate</span>::{Rng, SeedableRng}; + + <span class="attribute">#[test] + </span><span class="kw">fn </span>test_reseeding() { + <span class="kw">let </span><span class="kw-2">mut </span>zero = StepRng::new(<span class="number">0</span>, <span class="number">0</span>); + <span class="kw">let </span>rng = Core::from_rng(<span class="kw-2">&mut </span>zero).unwrap(); + <span class="kw">let </span>thresh = <span class="number">1</span>; <span class="comment">// reseed every time the buffer is exhausted + </span><span class="kw">let </span><span class="kw-2">mut </span>reseeding = ReseedingRng::new(rng, thresh, zero); + + <span class="comment">// RNG buffer size is [u32; 64] + // Debug is only implemented up to length 32 so use two arrays + </span><span class="kw">let </span><span class="kw-2">mut </span>buf = ([<span class="number">0u32</span>; <span class="number">32</span>], [<span class="number">0u32</span>; <span class="number">32</span>]); + reseeding.fill(<span class="kw-2">&mut </span>buf.<span class="number">0</span>); + reseeding.fill(<span class="kw-2">&mut </span>buf.<span class="number">1</span>); + <span class="kw">let </span>seq = buf; + <span class="kw">for _ in </span><span class="number">0</span>..<span class="number">10 </span>{ + reseeding.fill(<span class="kw-2">&mut </span>buf.<span class="number">0</span>); + reseeding.fill(<span class="kw-2">&mut </span>buf.<span class="number">1</span>); + <span class="macro">assert_eq!</span>(buf, seq); + } + } + + <span class="attribute">#[test] + </span><span class="kw">fn </span>test_clone_reseeding() { + <span class="attribute">#![allow(clippy::redundant_clone)] + + </span><span class="kw">let </span><span class="kw-2">mut </span>zero = StepRng::new(<span class="number">0</span>, <span class="number">0</span>); + <span class="kw">let </span>rng = Core::from_rng(<span class="kw-2">&mut </span>zero).unwrap(); + <span class="kw">let </span><span class="kw-2">mut </span>rng1 = ReseedingRng::new(rng, <span class="number">32 </span>* <span class="number">4</span>, zero); + + <span class="kw">let </span>first: u32 = rng1.gen(); + <span class="kw">for _ in </span><span class="number">0</span>..<span class="number">10 </span>{ + <span class="kw">let _ </span>= rng1.gen::<u32>(); + } + + <span class="kw">let </span><span class="kw-2">mut </span>rng2 = rng1.clone(); + <span class="macro">assert_eq!</span>(first, rng2.gen::<u32>()); + } +} +</code></pre></div> +</section></div></main><div id="rustdoc-vars" data-root-path="../../../../" data-current-crate="rand" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0 (69f9c33d7 2022-12-12) (Arch Linux rust 1:1.66.0-1)" ></div></body></html>
\ No newline at end of file diff --git a/rust/theBook/chapter-2-guessing-game/guessing_game/target/doc/src/rand/rngs/mock.rs.html b/rust/theBook/chapter-2-guessing-game/guessing_game/target/doc/src/rand/rngs/mock.rs.html new file mode 100644 index 0000000..819baf1 --- /dev/null +++ b/rust/theBook/chapter-2-guessing-game/guessing_game/target/doc/src/rand/rngs/mock.rs.html @@ -0,0 +1,177 @@ +<!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 `/home/pico/.local/share/cargo/registry/src/github.com-1ecc6299db9ec823/rand-0.8.5/src/rngs/mock.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>mock.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 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src="../../../wheel.svg"></a></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 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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> +</pre><pre class="rust"><code><span class="comment">// Copyright 2018 Developers of the Rand project. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +</span><span class="doccomment">//! Mock random number generator + +</span><span class="kw">use </span>rand_core::{impls, Error, RngCore}; + +<span class="attribute">#[cfg(feature = <span class="string">"serde1"</span>)] +</span><span class="kw">use </span>serde::{Serialize, Deserialize}; + +<span class="doccomment">/// A simple implementation of `RngCore` for testing purposes. +/// +/// This generates an arithmetic sequence (i.e. adds a constant each step) +/// over a `u64` number, using wrapping arithmetic. If the increment is 0 +/// the generator yields a constant. +/// +/// ``` +/// use rand::Rng; +/// use rand::rngs::mock::StepRng; +/// +/// let mut my_rng = StepRng::new(2, 1); +/// let sample: [u64; 3] = my_rng.gen(); +/// assert_eq!(sample, [2, 3, 4]); +/// ``` +</span><span class="attribute">#[derive(Debug, Clone, PartialEq, Eq)] +#[cfg_attr(feature = <span class="string">"serde1"</span>, derive(Serialize, Deserialize))] +</span><span class="kw">pub struct </span>StepRng { + v: u64, + a: u64, +} + +<span class="kw">impl </span>StepRng { + <span class="doccomment">/// Create a `StepRng`, yielding an arithmetic sequence starting with + /// `initial` and incremented by `increment` each time. + </span><span class="kw">pub fn </span>new(initial: u64, increment: u64) -> <span class="self">Self </span>{ + StepRng { + v: initial, + a: increment, + } + } +} + +<span class="kw">impl </span>RngCore <span class="kw">for </span>StepRng { + <span class="attribute">#[inline] + </span><span class="kw">fn </span>next_u32(<span class="kw-2">&mut </span><span class="self">self</span>) -> u32 { + <span class="self">self</span>.next_u64() <span class="kw">as </span>u32 + } + + <span class="attribute">#[inline] + </span><span class="kw">fn </span>next_u64(<span class="kw-2">&mut </span><span class="self">self</span>) -> u64 { + <span class="kw">let </span>result = <span class="self">self</span>.v; + <span class="self">self</span>.v = <span class="self">self</span>.v.wrapping_add(<span class="self">self</span>.a); + result + } + + <span class="attribute">#[inline] + </span><span class="kw">fn </span>fill_bytes(<span class="kw-2">&mut </span><span class="self">self</span>, dest: <span class="kw-2">&mut </span>[u8]) { + impls::fill_bytes_via_next(<span class="self">self</span>, dest); + } + + <span class="attribute">#[inline] + </span><span class="kw">fn </span>try_fill_bytes(<span class="kw-2">&mut </span><span class="self">self</span>, dest: <span class="kw-2">&mut </span>[u8]) -> <span class="prelude-ty">Result</span><(), Error> { + <span class="self">self</span>.fill_bytes(dest); + <span class="prelude-val">Ok</span>(()) + } +} + +<span class="attribute">#[cfg(test)] +</span><span class="kw">mod </span>tests { + <span class="attribute">#[test] + #[cfg(feature = <span class="string">"serde1"</span>)] + </span><span class="kw">fn </span>test_serialization_step_rng() { + <span class="kw">use </span><span class="kw">super</span>::StepRng; + + <span class="kw">let </span>some_rng = StepRng::new(<span class="number">42</span>, <span class="number">7</span>); + <span class="kw">let </span>de_some_rng: StepRng = + bincode::deserialize(<span class="kw-2">&</span>bincode::serialize(<span class="kw-2">&</span>some_rng).unwrap()).unwrap(); + <span class="macro">assert_eq!</span>(some_rng.v, de_some_rng.v); + <span class="macro">assert_eq!</span>(some_rng.a, de_some_rng.a); + + } +} +</code></pre></div> +</section></div></main><div id="rustdoc-vars" data-root-path="../../../" data-current-crate="rand" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0 (69f9c33d7 2022-12-12) (Arch Linux rust 1:1.66.0-1)" ></div></body></html>
\ No newline at end of file diff --git a/rust/theBook/chapter-2-guessing-game/guessing_game/target/doc/src/rand/rngs/mod.rs.html b/rust/theBook/chapter-2-guessing-game/guessing_game/target/doc/src/rand/rngs/mod.rs.html new file mode 100644 index 0000000..48767fa --- /dev/null +++ b/rust/theBook/chapter-2-guessing-game/guessing_game/target/doc/src/rand/rngs/mod.rs.html @@ -0,0 +1,241 @@ +<!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 `/home/pico/.local/share/cargo/registry/src/github.com-1ecc6299db9ec823/rand-0.8.5/src/rngs/mod.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>mod.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="icon" href="https://www.rust-lang.org/favicon.ico"></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"></nav><main><div class="width-limiter"><nav class="sub"><a class="sub-logo-container" href="../../../rand/index.html"> + <img src="https://www.rust-lang.org/logos/rust-logo-128x128-blk.png" alt="logo"></a><form class="search-form"><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></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 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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> +</pre><pre class="rust"><code><span class="comment">// Copyright 2018 Developers of the Rand project. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +</span><span class="doccomment">//! Random number generators and adapters +//! +//! ## Background: Random number generators (RNGs) +//! +//! Computers cannot produce random numbers from nowhere. We classify +//! random number generators as follows: +//! +//! - "True" random number generators (TRNGs) use hard-to-predict data sources +//! (e.g. the high-resolution parts of event timings and sensor jitter) to +//! harvest random bit-sequences, apply algorithms to remove bias and +//! estimate available entropy, then combine these bits into a byte-sequence +//! or an entropy pool. This job is usually done by the operating system or +//! a hardware generator (HRNG). +//! - "Pseudo"-random number generators (PRNGs) use algorithms to transform a +//! seed into a sequence of pseudo-random numbers. These generators can be +//! fast and produce well-distributed unpredictable random numbers (or not). +//! They are usually deterministic: given algorithm and seed, the output +//! sequence can be reproduced. They have finite period and eventually loop; +//! with many algorithms this period is fixed and can be proven sufficiently +//! long, while others are chaotic and the period depends on the seed. +//! - "Cryptographically secure" pseudo-random number generators (CSPRNGs) +//! are the sub-set of PRNGs which are secure. Security of the generator +//! relies both on hiding the internal state and using a strong algorithm. +//! +//! ## Traits and functionality +//! +//! All RNGs implement the [`RngCore`] trait, as a consequence of which the +//! [`Rng`] extension trait is automatically implemented. Secure RNGs may +//! additionally implement the [`CryptoRng`] trait. +//! +//! All PRNGs require a seed to produce their random number sequence. The +//! [`SeedableRng`] trait provides three ways of constructing PRNGs: +//! +//! - `from_seed` accepts a type specific to the PRNG +//! - `from_rng` allows a PRNG to be seeded from any other RNG +//! - `seed_from_u64` allows any PRNG to be seeded from a `u64` insecurely +//! - `from_entropy` securely seeds a PRNG from fresh entropy +//! +//! Use the [`rand_core`] crate when implementing your own RNGs. +//! +//! ## Our generators +//! +//! This crate provides several random number generators: +//! +//! - [`OsRng`] is an interface to the operating system's random number +//! source. Typically the operating system uses a CSPRNG with entropy +//! provided by a TRNG and some type of on-going re-seeding. +//! - [`ThreadRng`], provided by the [`thread_rng`] function, is a handle to a +//! thread-local CSPRNG with periodic seeding from [`OsRng`]. Because this +//! is local, it is typically much faster than [`OsRng`]. It should be +//! secure, though the paranoid may prefer [`OsRng`]. +//! - [`StdRng`] is a CSPRNG chosen for good performance and trust of security +//! (based on reviews, maturity and usage). The current algorithm is ChaCha12, +//! which is well established and rigorously analysed. +//! [`StdRng`] provides the algorithm used by [`ThreadRng`] but without +//! periodic reseeding. +//! - [`SmallRng`] is an **insecure** PRNG designed to be fast, simple, require +//! little memory, and have good output quality. +//! +//! The algorithms selected for [`StdRng`] and [`SmallRng`] may change in any +//! release and may be platform-dependent, therefore they should be considered +//! **not reproducible**. +//! +//! ## Additional generators +//! +//! **TRNGs**: The [`rdrand`] crate provides an interface to the RDRAND and +//! RDSEED instructions available in modern Intel and AMD CPUs. +//! The [`rand_jitter`] crate provides a user-space implementation of +//! entropy harvesting from CPU timer jitter, but is very slow and has +//! [security issues](https://github.com/rust-random/rand/issues/699). +//! +//! **PRNGs**: Several companion crates are available, providing individual or +//! families of PRNG algorithms. These provide the implementations behind +//! [`StdRng`] and [`SmallRng`] but can also be used directly, indeed *should* +//! be used directly when **reproducibility** matters. +//! Some suggestions are: [`rand_chacha`], [`rand_pcg`], [`rand_xoshiro`]. +//! A full list can be found by searching for crates with the [`rng` tag]. +//! +//! [`Rng`]: crate::Rng +//! [`RngCore`]: crate::RngCore +//! [`CryptoRng`]: crate::CryptoRng +//! [`SeedableRng`]: crate::SeedableRng +//! [`thread_rng`]: crate::thread_rng +//! [`rdrand`]: https://crates.io/crates/rdrand +//! [`rand_jitter`]: https://crates.io/crates/rand_jitter +//! [`rand_chacha`]: https://crates.io/crates/rand_chacha +//! [`rand_pcg`]: https://crates.io/crates/rand_pcg +//! [`rand_xoshiro`]: https://crates.io/crates/rand_xoshiro +//! [`rng` tag]: https://crates.io/keywords/rng + +</span><span class="attribute">#[cfg_attr(doc_cfg, doc(cfg(feature = <span class="string">"std"</span>)))] +#[cfg(feature = <span class="string">"std"</span>)] </span><span class="kw">pub mod </span>adapter; + +<span class="kw">pub mod </span>mock; <span class="comment">// Public so we don't export `StepRng` directly, making it a bit + // more clear it is intended for testing. + +</span><span class="attribute">#[cfg(all(feature = <span class="string">"small_rng"</span>, target_pointer_width = <span class="string">"64"</span>))] +</span><span class="kw">mod </span>xoshiro256plusplus; +<span class="attribute">#[cfg(all(feature = <span class="string">"small_rng"</span>, not(target_pointer_width = <span class="string">"64"</span>)))] +</span><span class="kw">mod </span>xoshiro128plusplus; +<span class="attribute">#[cfg(feature = <span class="string">"small_rng"</span>)] </span><span class="kw">mod </span>small; + +<span class="attribute">#[cfg(feature = <span class="string">"std_rng"</span>)] </span><span class="kw">mod </span>std; +<span class="attribute">#[cfg(all(feature = <span class="string">"std"</span>, feature = <span class="string">"std_rng"</span>))] </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">mod </span>thread; + +<span class="attribute">#[cfg(feature = <span class="string">"small_rng"</span>)] </span><span class="kw">pub use </span><span class="self">self</span>::small::SmallRng; +<span class="attribute">#[cfg(feature = <span class="string">"std_rng"</span>)] </span><span class="kw">pub use </span><span class="self">self</span>::std::StdRng; +<span class="attribute">#[cfg(all(feature = <span class="string">"std"</span>, feature = <span class="string">"std_rng"</span>))] </span><span class="kw">pub use </span><span class="self">self</span>::thread::ThreadRng; + +<span class="attribute">#[cfg_attr(doc_cfg, doc(cfg(feature = <span class="string">"getrandom"</span>)))] +#[cfg(feature = <span class="string">"getrandom"</span>)] </span><span class="kw">pub use </span>rand_core::OsRng; +</code></pre></div> +</section></div></main><div id="rustdoc-vars" data-root-path="../../../" data-current-crate="rand" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0 (69f9c33d7 2022-12-12) (Arch Linux rust 1:1.66.0-1)" ></div></body></html>
\ No newline at end of file diff --git a/rust/theBook/chapter-2-guessing-game/guessing_game/target/doc/src/rand/rngs/std.rs.html b/rust/theBook/chapter-2-guessing-game/guessing_game/target/doc/src/rand/rngs/std.rs.html new file mode 100644 index 0000000..a7d324f --- /dev/null +++ b/rust/theBook/chapter-2-guessing-game/guessing_game/target/doc/src/rand/rngs/std.rs.html @@ -0,0 +1,199 @@ +<!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 `/home/pico/.local/share/cargo/registry/src/github.com-1ecc6299db9ec823/rand-0.8.5/src/rngs/std.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>std.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 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src="../../../main.js"></script><noscript><link rel="stylesheet" href="../../../noscript.css"></noscript><link rel="icon" href="https://www.rust-lang.org/favicon.ico"></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"></nav><main><div class="width-limiter"><nav class="sub"><a class="sub-logo-container" href="../../../rand/index.html"> + <img src="https://www.rust-lang.org/logos/rust-logo-128x128-blk.png" alt="logo"></a><form class="search-form"><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></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> +</pre><pre class="rust"><code><span class="comment">// Copyright 2018 Developers of the Rand project. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +</span><span class="doccomment">//! The standard RNG + +</span><span class="kw">use crate</span>::{CryptoRng, Error, RngCore, SeedableRng}; + +<span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">use </span>rand_chacha::ChaCha12Core <span class="kw">as </span>Core; + +<span class="kw">use </span>rand_chacha::ChaCha12Rng <span class="kw">as </span>Rng; + +<span class="doccomment">/// The standard RNG. The PRNG algorithm in `StdRng` is chosen to be efficient +/// on the current platform, to be statistically strong and unpredictable +/// (meaning a cryptographically secure PRNG). +/// +/// The current algorithm used is the ChaCha block cipher with 12 rounds. Please +/// see this relevant [rand issue] for the discussion. This may change as new +/// evidence of cipher security and performance becomes available. +/// +/// The algorithm is deterministic but should not be considered reproducible +/// due to dependence on configuration and possible replacement in future +/// library versions. For a secure reproducible generator, we recommend use of +/// the [rand_chacha] crate directly. +/// +/// [rand_chacha]: https://crates.io/crates/rand_chacha +/// [rand issue]: https://github.com/rust-random/rand/issues/932 +</span><span class="attribute">#[cfg_attr(doc_cfg, doc(cfg(feature = <span class="string">"std_rng"</span>)))] +#[derive(Clone, Debug, PartialEq, Eq)] +</span><span class="kw">pub struct </span>StdRng(Rng); + +<span class="kw">impl </span>RngCore <span class="kw">for </span>StdRng { + <span class="attribute">#[inline(always)] + </span><span class="kw">fn </span>next_u32(<span class="kw-2">&mut </span><span class="self">self</span>) -> u32 { + <span class="self">self</span>.<span class="number">0</span>.next_u32() + } + + <span class="attribute">#[inline(always)] + </span><span class="kw">fn </span>next_u64(<span class="kw-2">&mut </span><span class="self">self</span>) -> u64 { + <span class="self">self</span>.<span class="number">0</span>.next_u64() + } + + <span class="attribute">#[inline(always)] + </span><span class="kw">fn </span>fill_bytes(<span class="kw-2">&mut </span><span class="self">self</span>, dest: <span class="kw-2">&mut </span>[u8]) { + <span class="self">self</span>.<span class="number">0</span>.fill_bytes(dest); + } + + <span class="attribute">#[inline(always)] + </span><span class="kw">fn </span>try_fill_bytes(<span class="kw-2">&mut </span><span class="self">self</span>, dest: <span class="kw-2">&mut </span>[u8]) -> <span class="prelude-ty">Result</span><(), Error> { + <span class="self">self</span>.<span class="number">0</span>.try_fill_bytes(dest) + } +} + +<span class="kw">impl </span>SeedableRng <span class="kw">for </span>StdRng { + <span class="kw">type </span>Seed = <Rng <span class="kw">as </span>SeedableRng>::Seed; + + <span class="attribute">#[inline(always)] + </span><span class="kw">fn </span>from_seed(seed: <span class="self">Self</span>::Seed) -> <span class="self">Self </span>{ + StdRng(Rng::from_seed(seed)) + } + + <span class="attribute">#[inline(always)] + </span><span class="kw">fn </span>from_rng<R: RngCore>(rng: R) -> <span class="prelude-ty">Result</span><<span class="self">Self</span>, Error> { + Rng::from_rng(rng).map(StdRng) + } +} + +<span class="kw">impl </span>CryptoRng <span class="kw">for </span>StdRng {} + + +<span class="attribute">#[cfg(test)] +</span><span class="kw">mod </span>test { + <span class="kw">use </span><span class="kw">crate</span>::rngs::StdRng; + <span class="kw">use crate</span>::{RngCore, SeedableRng}; + + <span class="attribute">#[test] + </span><span class="kw">fn </span>test_stdrng_construction() { + <span class="comment">// Test value-stability of StdRng. This is expected to break any time + // the algorithm is changed. + </span><span class="attribute">#[rustfmt::skip] + </span><span class="kw">let </span>seed = [<span class="number">1</span>,<span class="number">0</span>,<span class="number">0</span>,<span class="number">0</span>, <span class="number">23</span>,<span class="number">0</span>,<span class="number">0</span>,<span class="number">0</span>, <span class="number">200</span>,<span class="number">1</span>,<span class="number">0</span>,<span class="number">0</span>, <span class="number">210</span>,<span class="number">30</span>,<span class="number">0</span>,<span class="number">0</span>, + <span class="number">0</span>,<span class="number">0</span>,<span class="number">0</span>,<span class="number">0</span>, <span class="number">0</span>,<span class="number">0</span>,<span class="number">0</span>,<span class="number">0</span>, <span class="number">0</span>,<span class="number">0</span>,<span class="number">0</span>,<span class="number">0</span>, <span class="number">0</span>,<span class="number">0</span>,<span class="number">0</span>,<span class="number">0</span>]; + + <span class="kw">let </span>target = [<span class="number">10719222850664546238</span>, <span class="number">14064965282130556830</span>]; + + <span class="kw">let </span><span class="kw-2">mut </span>rng0 = StdRng::from_seed(seed); + <span class="kw">let </span>x0 = rng0.next_u64(); + + <span class="kw">let </span><span class="kw-2">mut </span>rng1 = StdRng::from_rng(rng0).unwrap(); + <span class="kw">let </span>x1 = rng1.next_u64(); + + <span class="macro">assert_eq!</span>([x0, x1], target); + } +} +</code></pre></div> +</section></div></main><div id="rustdoc-vars" data-root-path="../../../" data-current-crate="rand" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0 (69f9c33d7 2022-12-12) (Arch Linux rust 1:1.66.0-1)" ></div></body></html>
\ No newline at end of file diff --git a/rust/theBook/chapter-2-guessing-game/guessing_game/target/doc/src/rand/rngs/thread.rs.html b/rust/theBook/chapter-2-guessing-game/guessing_game/target/doc/src/rand/rngs/thread.rs.html new file mode 100644 index 0000000..5243758 --- /dev/null +++ b/rust/theBook/chapter-2-guessing-game/guessing_game/target/doc/src/rand/rngs/thread.rs.html @@ -0,0 +1,289 @@ +<!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 `/home/pico/.local/share/cargo/registry/src/github.com-1ecc6299db9ec823/rand-0.8.5/src/rngs/thread.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>thread.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 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src="../../../wheel.svg"></a></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 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+<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> +</pre><pre class="rust"><code><span class="comment">// Copyright 2018 Developers of the Rand project. +// +// Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or +// https://www.apache.org/licenses/LICENSE-2.0> or the MIT license +// <LICENSE-MIT or https://opensource.org/licenses/MIT>, at your +// option. This file may not be copied, modified, or distributed +// except according to those terms. + +</span><span class="doccomment">//! Thread-local random number generator + +</span><span class="kw">use </span>core::cell::UnsafeCell; +<span class="kw">use </span>std::rc::Rc; +<span class="kw">use </span>std::thread_local; + +<span class="kw">use </span><span class="kw">super</span>::std::Core; +<span class="kw">use </span><span class="kw">crate</span>::rngs::adapter::ReseedingRng; +<span class="kw">use </span><span class="kw">crate</span>::rngs::OsRng; +<span class="kw">use crate</span>::{CryptoRng, Error, RngCore, SeedableRng}; + +<span class="comment">// Rationale for using `UnsafeCell` in `ThreadRng`: +// +// Previously we used a `RefCell`, with an overhead of ~15%. There will only +// ever be one mutable reference to the interior of the `UnsafeCell`, because +// we only have such a reference inside `next_u32`, `next_u64`, etc. Within a +// single thread (which is the definition of `ThreadRng`), there will only ever +// be one of these methods active at a time. +// +// A possible scenario where there could be multiple mutable references is if +// `ThreadRng` is used inside `next_u32` and co. But the implementation is +// completely under our control. We just have to ensure none of them use +// `ThreadRng` internally, which is nonsensical anyway. We should also never run +// `ThreadRng` in destructors of its implementation, which is also nonsensical. + + +// Number of generated bytes after which to reseed `ThreadRng`. +// According to benchmarks, reseeding has a noticeable impact with thresholds +// of 32 kB and less. We choose 64 kB to avoid significant overhead. +</span><span class="kw">const </span>THREAD_RNG_RESEED_THRESHOLD: u64 = <span class="number">1024 </span>* <span class="number">64</span>; + +<span class="doccomment">/// A reference to the thread-local generator +/// +/// An instance can be obtained via [`thread_rng`] or via `ThreadRng::default()`. +/// This handle is safe to use everywhere (including thread-local destructors), +/// though it is recommended not to use inside a fork handler. +/// The handle cannot be passed between threads (is not `Send` or `Sync`). +/// +/// `ThreadRng` uses the same PRNG as [`StdRng`] for security and performance +/// and is automatically seeded from [`OsRng`]. +/// +/// Unlike `StdRng`, `ThreadRng` uses the [`ReseedingRng`] wrapper to reseed +/// the PRNG from fresh entropy every 64 kiB of random data as well as after a +/// fork on Unix (though not quite immediately; see documentation of +/// [`ReseedingRng`]). +/// Note that the reseeding is done as an extra precaution against side-channel +/// attacks and mis-use (e.g. if somehow weak entropy were supplied initially). +/// The PRNG algorithms used are assumed to be secure. +/// +/// [`ReseedingRng`]: crate::rngs::adapter::ReseedingRng +/// [`StdRng`]: crate::rngs::StdRng +</span><span class="attribute">#[cfg_attr(doc_cfg, doc(cfg(all(feature = <span class="string">"std"</span>, feature = <span class="string">"std_rng"</span>))))] +#[derive(Clone, Debug)] +</span><span class="kw">pub struct </span>ThreadRng { + <span class="comment">// Rc is explicitly !Send and !Sync + </span>rng: Rc<UnsafeCell<ReseedingRng<Core, OsRng>>>, +} + +<span class="macro">thread_local!</span>( + <span class="comment">// We require Rc<..> to avoid premature freeing when thread_rng is used + // within thread-local destructors. See #968. + </span><span class="kw">static </span>THREAD_RNG_KEY: Rc<UnsafeCell<ReseedingRng<Core, OsRng>>> = { + <span class="kw">let </span>r = Core::from_rng(OsRng).unwrap_or_else(|err| + <span class="macro">panic!</span>(<span class="string">"could not initialize thread_rng: {}"</span>, err)); + <span class="kw">let </span>rng = ReseedingRng::new(r, + THREAD_RNG_RESEED_THRESHOLD, + OsRng); + Rc::new(UnsafeCell::new(rng)) + } +); + +<span class="doccomment">/// Retrieve the lazily-initialized thread-local random number generator, +/// seeded by the system. Intended to be used in method chaining style, +/// e.g. `thread_rng().gen::<i32>()`, or cached locally, e.g. +/// `let mut rng = thread_rng();`. Invoked by the `Default` trait, making +/// `ThreadRng::default()` equivalent. +/// +/// For more information see [`ThreadRng`]. +</span><span class="attribute">#[cfg_attr(doc_cfg, doc(cfg(all(feature = <span class="string">"std"</span>, feature = <span class="string">"std_rng"</span>))))] +</span><span class="kw">pub fn </span>thread_rng() -> ThreadRng { + <span class="kw">let </span>rng = THREAD_RNG_KEY.with(|t| t.clone()); + ThreadRng { rng } +} + +<span class="kw">impl </span>Default <span class="kw">for </span>ThreadRng { + <span class="kw">fn </span>default() -> ThreadRng { + <span class="kw">crate</span>::prelude::thread_rng() + } +} + +<span class="kw">impl </span>RngCore <span class="kw">for </span>ThreadRng { + <span class="attribute">#[inline(always)] + </span><span class="kw">fn </span>next_u32(<span class="kw-2">&mut </span><span class="self">self</span>) -> u32 { + <span class="comment">// SAFETY: We must make sure to stop using `rng` before anyone else + // creates another mutable reference + </span><span class="kw">let </span>rng = <span class="kw">unsafe </span>{ <span class="kw-2">&mut *</span><span class="self">self</span>.rng.get() }; + rng.next_u32() + } + + <span class="attribute">#[inline(always)] + </span><span class="kw">fn </span>next_u64(<span class="kw-2">&mut </span><span class="self">self</span>) -> u64 { + <span class="comment">// SAFETY: We must make sure to stop using `rng` before anyone else + // creates another mutable reference + </span><span class="kw">let </span>rng = <span class="kw">unsafe </span>{ <span class="kw-2">&mut *</span><span class="self">self</span>.rng.get() }; + rng.next_u64() + } + + <span class="kw">fn </span>fill_bytes(<span class="kw-2">&mut </span><span class="self">self</span>, dest: <span class="kw-2">&mut </span>[u8]) { + <span class="comment">// SAFETY: We must make sure to stop using `rng` before anyone else + // creates another mutable reference + </span><span class="kw">let </span>rng = <span class="kw">unsafe </span>{ <span class="kw-2">&mut *</span><span class="self">self</span>.rng.get() }; + rng.fill_bytes(dest) + } + + <span class="kw">fn </span>try_fill_bytes(<span class="kw-2">&mut </span><span class="self">self</span>, dest: <span class="kw-2">&mut </span>[u8]) -> <span class="prelude-ty">Result</span><(), Error> { + <span class="comment">// SAFETY: We must make sure to stop using `rng` before anyone else + // creates another mutable reference + </span><span class="kw">let </span>rng = <span class="kw">unsafe </span>{ <span class="kw-2">&mut *</span><span class="self">self</span>.rng.get() }; + rng.try_fill_bytes(dest) + } +} + +<span class="kw">impl </span>CryptoRng <span class="kw">for </span>ThreadRng {} + + +<span class="attribute">#[cfg(test)] +</span><span class="kw">mod </span>test { + <span class="attribute">#[test] + </span><span class="kw">fn </span>test_thread_rng() { + <span class="kw">use </span><span class="kw">crate</span>::Rng; + <span class="kw">let </span><span class="kw-2">mut </span>r = <span class="kw">crate</span>::thread_rng(); + r.gen::<i32>(); + <span class="macro">assert_eq!</span>(r.gen_range(<span class="number">0</span>..<span class="number">1</span>), <span class="number">0</span>); + } +} +</code></pre></div> +</section></div></main><div id="rustdoc-vars" data-root-path="../../../" data-current-crate="rand" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0 (69f9c33d7 2022-12-12) (Arch Linux rust 1:1.66.0-1)" ></div></body></html>
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