| <!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/bytes-1.4.0/src/bytes.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>bytes.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="../../bytes/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="../../bytes/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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| <span id="1076">1076</span> |
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| <span id="1078">1078</span> |
| <span id="1079">1079</span> |
| <span id="1080">1080</span> |
| <span id="1081">1081</span> |
| <span id="1082">1082</span> |
| <span id="1083">1083</span> |
| <span id="1084">1084</span> |
| <span id="1085">1085</span> |
| <span id="1086">1086</span> |
| <span id="1087">1087</span> |
| <span id="1088">1088</span> |
| <span id="1089">1089</span> |
| <span id="1090">1090</span> |
| <span id="1091">1091</span> |
| <span id="1092">1092</span> |
| <span id="1093">1093</span> |
| <span id="1094">1094</span> |
| <span id="1095">1095</span> |
| <span id="1096">1096</span> |
| <span id="1097">1097</span> |
| <span id="1098">1098</span> |
| <span id="1099">1099</span> |
| <span id="1100">1100</span> |
| <span id="1101">1101</span> |
| <span id="1102">1102</span> |
| <span id="1103">1103</span> |
| <span id="1104">1104</span> |
| <span id="1105">1105</span> |
| <span id="1106">1106</span> |
| <span id="1107">1107</span> |
| <span id="1108">1108</span> |
| <span id="1109">1109</span> |
| <span id="1110">1110</span> |
| <span id="1111">1111</span> |
| <span id="1112">1112</span> |
| <span id="1113">1113</span> |
| <span id="1114">1114</span> |
| <span id="1115">1115</span> |
| <span id="1116">1116</span> |
| <span id="1117">1117</span> |
| <span id="1118">1118</span> |
| <span id="1119">1119</span> |
| <span id="1120">1120</span> |
| <span id="1121">1121</span> |
| <span id="1122">1122</span> |
| <span id="1123">1123</span> |
| <span id="1124">1124</span> |
| <span id="1125">1125</span> |
| <span id="1126">1126</span> |
| <span id="1127">1127</span> |
| <span id="1128">1128</span> |
| <span id="1129">1129</span> |
| <span id="1130">1130</span> |
| <span id="1131">1131</span> |
| <span id="1132">1132</span> |
| <span id="1133">1133</span> |
| <span id="1134">1134</span> |
| <span id="1135">1135</span> |
| <span id="1136">1136</span> |
| <span id="1137">1137</span> |
| <span id="1138">1138</span> |
| <span id="1139">1139</span> |
| <span id="1140">1140</span> |
| <span id="1141">1141</span> |
| <span id="1142">1142</span> |
| <span id="1143">1143</span> |
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| <span id="1145">1145</span> |
| <span id="1146">1146</span> |
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| <span id="1148">1148</span> |
| <span id="1149">1149</span> |
| <span id="1150">1150</span> |
| <span id="1151">1151</span> |
| <span id="1152">1152</span> |
| <span id="1153">1153</span> |
| <span id="1154">1154</span> |
| <span id="1155">1155</span> |
| <span id="1156">1156</span> |
| <span id="1157">1157</span> |
| <span id="1158">1158</span> |
| <span id="1159">1159</span> |
| <span id="1160">1160</span> |
| <span id="1161">1161</span> |
| <span id="1162">1162</span> |
| <span id="1163">1163</span> |
| <span id="1164">1164</span> |
| <span id="1165">1165</span> |
| <span id="1166">1166</span> |
| <span id="1167">1167</span> |
| <span id="1168">1168</span> |
| <span id="1169">1169</span> |
| <span id="1170">1170</span> |
| <span id="1171">1171</span> |
| <span id="1172">1172</span> |
| <span id="1173">1173</span> |
| <span id="1174">1174</span> |
| <span id="1175">1175</span> |
| <span id="1176">1176</span> |
| <span id="1177">1177</span> |
| <span id="1178">1178</span> |
| <span id="1179">1179</span> |
| <span id="1180">1180</span> |
| <span id="1181">1181</span> |
| <span id="1182">1182</span> |
| <span id="1183">1183</span> |
| <span id="1184">1184</span> |
| <span id="1185">1185</span> |
| <span id="1186">1186</span> |
| <span id="1187">1187</span> |
| <span id="1188">1188</span> |
| <span id="1189">1189</span> |
| <span id="1190">1190</span> |
| <span id="1191">1191</span> |
| <span id="1192">1192</span> |
| <span id="1193">1193</span> |
| <span id="1194">1194</span> |
| <span id="1195">1195</span> |
| <span id="1196">1196</span> |
| <span id="1197">1197</span> |
| <span id="1198">1198</span> |
| <span id="1199">1199</span> |
| <span id="1200">1200</span> |
| <span id="1201">1201</span> |
| <span id="1202">1202</span> |
| <span id="1203">1203</span> |
| <span id="1204">1204</span> |
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| <span id="1214">1214</span> |
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| <span id="1216">1216</span> |
| <span id="1217">1217</span> |
| <span id="1218">1218</span> |
| <span id="1219">1219</span> |
| <span id="1220">1220</span> |
| <span id="1221">1221</span> |
| <span id="1222">1222</span> |
| <span id="1223">1223</span> |
| <span id="1224">1224</span> |
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| <span id="1228">1228</span> |
| <span id="1229">1229</span> |
| <span id="1230">1230</span> |
| <span id="1231">1231</span> |
| <span id="1232">1232</span> |
| <span id="1233">1233</span> |
| <span id="1234">1234</span> |
| <span id="1235">1235</span> |
| <span id="1236">1236</span> |
| <span id="1237">1237</span> |
| <span id="1238">1238</span> |
| <span id="1239">1239</span> |
| <span id="1240">1240</span> |
| <span id="1241">1241</span> |
| <span id="1242">1242</span> |
| <span id="1243">1243</span> |
| <span id="1244">1244</span> |
| <span id="1245">1245</span> |
| <span id="1246">1246</span> |
| <span id="1247">1247</span> |
| <span id="1248">1248</span> |
| <span id="1249">1249</span> |
| <span id="1250">1250</span> |
| <span id="1251">1251</span> |
| <span id="1252">1252</span> |
| <span id="1253">1253</span> |
| <span id="1254">1254</span> |
| <span id="1255">1255</span> |
| <span id="1256">1256</span> |
| <span id="1257">1257</span> |
| <span id="1258">1258</span> |
| <span id="1259">1259</span> |
| <span id="1260">1260</span> |
| <span id="1261">1261</span> |
| <span id="1262">1262</span> |
| <span id="1263">1263</span> |
| <span id="1264">1264</span> |
| <span id="1265">1265</span> |
| <span id="1266">1266</span> |
| <span id="1267">1267</span> |
| <span id="1268">1268</span> |
| <span id="1269">1269</span> |
| <span id="1270">1270</span> |
| <span id="1271">1271</span> |
| <span id="1272">1272</span> |
| <span id="1273">1273</span> |
| <span id="1274">1274</span> |
| <span id="1275">1275</span> |
| <span id="1276">1276</span> |
| <span id="1277">1277</span> |
| <span id="1278">1278</span> |
| <span id="1279">1279</span> |
| <span id="1280">1280</span> |
| <span id="1281">1281</span> |
| <span id="1282">1282</span> |
| <span id="1283">1283</span> |
| <span id="1284">1284</span> |
| <span id="1285">1285</span> |
| <span id="1286">1286</span> |
| <span id="1287">1287</span> |
| <span id="1288">1288</span> |
| <span id="1289">1289</span> |
| <span id="1290">1290</span> |
| <span id="1291">1291</span> |
| <span id="1292">1292</span> |
| <span id="1293">1293</span> |
| <span id="1294">1294</span> |
| <span id="1295">1295</span> |
| <span id="1296">1296</span> |
| <span id="1297">1297</span> |
| <span id="1298">1298</span> |
| <span id="1299">1299</span> |
| <span id="1300">1300</span> |
| <span id="1301">1301</span> |
| <span id="1302">1302</span> |
| <span id="1303">1303</span> |
| <span id="1304">1304</span> |
| </pre><pre class="rust"><code><span class="kw">use </span>core::iter::FromIterator; |
| <span class="kw">use </span>core::ops::{Deref, RangeBounds}; |
| <span class="kw">use </span>core::{cmp, fmt, hash, mem, ptr, slice, usize}; |
| |
| <span class="kw">use </span>alloc::{ |
| alloc::{dealloc, Layout}, |
| borrow::Borrow, |
| boxed::Box, |
| string::String, |
| vec::Vec, |
| }; |
| |
| <span class="kw">use </span><span class="kw">crate</span>::buf::IntoIter; |
| <span class="attribute">#[allow(unused)] |
| </span><span class="kw">use </span><span class="kw">crate</span>::loom::sync::atomic::AtomicMut; |
| <span class="kw">use </span><span class="kw">crate</span>::loom::sync::atomic::{AtomicPtr, AtomicUsize, Ordering}; |
| <span class="kw">use </span><span class="kw">crate</span>::Buf; |
| |
| <span class="doccomment">/// A cheaply cloneable and sliceable chunk of contiguous memory. |
| /// |
| /// `Bytes` is an efficient container for storing and operating on contiguous |
| /// slices of memory. It is intended for use primarily in networking code, but |
| /// could have applications elsewhere as well. |
| /// |
| /// `Bytes` values facilitate zero-copy network programming by allowing multiple |
| /// `Bytes` objects to point to the same underlying memory. |
| /// |
| /// `Bytes` does not have a single implementation. It is an interface, whose |
| /// exact behavior is implemented through dynamic dispatch in several underlying |
| /// implementations of `Bytes`. |
| /// |
| /// All `Bytes` implementations must fulfill the following requirements: |
| /// - They are cheaply cloneable and thereby shareable between an unlimited amount |
| /// of components, for example by modifying a reference count. |
| /// - Instances can be sliced to refer to a subset of the original buffer. |
| /// |
| /// ``` |
| /// use bytes::Bytes; |
| /// |
| /// let mut mem = Bytes::from("Hello world"); |
| /// let a = mem.slice(0..5); |
| /// |
| /// assert_eq!(a, "Hello"); |
| /// |
| /// let b = mem.split_to(6); |
| /// |
| /// assert_eq!(mem, "world"); |
| /// assert_eq!(b, "Hello "); |
| /// ``` |
| /// |
| /// # Memory layout |
| /// |
| /// The `Bytes` struct itself is fairly small, limited to 4 `usize` fields used |
| /// to track information about which segment of the underlying memory the |
| /// `Bytes` handle has access to. |
| /// |
| /// `Bytes` keeps both a pointer to the shared state containing the full memory |
| /// slice and a pointer to the start of the region visible by the handle. |
| /// `Bytes` also tracks the length of its view into the memory. |
| /// |
| /// # Sharing |
| /// |
| /// `Bytes` contains a vtable, which allows implementations of `Bytes` to define |
| /// how sharing/cloning is implemented in detail. |
| /// When `Bytes::clone()` is called, `Bytes` will call the vtable function for |
| /// cloning the backing storage in order to share it behind between multiple |
| /// `Bytes` instances. |
| /// |
| /// For `Bytes` implementations which refer to constant memory (e.g. created |
| /// via `Bytes::from_static()`) the cloning implementation will be a no-op. |
| /// |
| /// For `Bytes` implementations which point to a reference counted shared storage |
| /// (e.g. an `Arc<[u8]>`), sharing will be implemented by increasing the |
| /// reference count. |
| /// |
| /// Due to this mechanism, multiple `Bytes` instances may point to the same |
| /// shared memory region. |
| /// Each `Bytes` instance can point to different sections within that |
| /// memory region, and `Bytes` instances may or may not have overlapping views |
| /// into the memory. |
| /// |
| /// The following diagram visualizes a scenario where 2 `Bytes` instances make |
| /// use of an `Arc`-based backing storage, and provide access to different views: |
| /// |
| /// ```text |
| /// |
| /// Arc ptrs ┌─────────┐ |
| /// ________________________ / │ Bytes 2 │ |
| /// / └─────────┘ |
| /// / ┌───────────┐ | | |
| /// |_________/ │ Bytes 1 │ | | |
| /// | └───────────┘ | | |
| /// | | | ___/ data | tail |
| /// | data | tail |/ | |
| /// v v v v |
| /// ┌─────┬─────┬───────────┬───────────────┬─────┐ |
| /// │ Arc │ │ │ │ │ |
| /// └─────┴─────┴───────────┴───────────────┴─────┘ |
| /// ``` |
| </span><span class="kw">pub struct </span>Bytes { |
| ptr: <span class="kw-2">*const </span>u8, |
| len: usize, |
| <span class="comment">// inlined "trait object" |
| </span>data: AtomicPtr<()>, |
| vtable: <span class="kw-2">&</span><span class="lifetime">'static </span>Vtable, |
| } |
| |
| <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">struct </span>Vtable { |
| <span class="doccomment">/// fn(data, ptr, len) |
| </span><span class="kw">pub </span>clone: <span class="kw">unsafe fn</span>(<span class="kw-2">&</span>AtomicPtr<()>, <span class="kw-2">*const </span>u8, usize) -> Bytes, |
| <span class="doccomment">/// fn(data, ptr, len) |
| /// |
| /// takes `Bytes` to value |
| </span><span class="kw">pub </span>to_vec: <span class="kw">unsafe fn</span>(<span class="kw-2">&</span>AtomicPtr<()>, <span class="kw-2">*const </span>u8, usize) -> Vec<u8>, |
| <span class="doccomment">/// fn(data, ptr, len) |
| </span><span class="kw">pub </span>drop: <span class="kw">unsafe fn</span>(<span class="kw-2">&mut </span>AtomicPtr<()>, <span class="kw-2">*const </span>u8, usize), |
| } |
| |
| <span class="kw">impl </span>Bytes { |
| <span class="doccomment">/// Creates a new empty `Bytes`. |
| /// |
| /// This will not allocate and the returned `Bytes` handle will be empty. |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| /// use bytes::Bytes; |
| /// |
| /// let b = Bytes::new(); |
| /// assert_eq!(&b[..], b""); |
| /// ``` |
| </span><span class="attribute">#[inline] |
| #[cfg(not(all(loom, test)))] |
| </span><span class="kw">pub const fn </span>new() -> <span class="self">Self </span>{ |
| <span class="comment">// Make it a named const to work around |
| // "unsizing casts are not allowed in const fn" |
| </span><span class="kw">const </span>EMPTY: <span class="kw-2">&</span>[u8] = <span class="kw-2">&</span>[]; |
| Bytes::from_static(EMPTY) |
| } |
| |
| <span class="attribute">#[cfg(all(loom, test))] |
| </span><span class="kw">pub fn </span>new() -> <span class="self">Self </span>{ |
| <span class="kw">const </span>EMPTY: <span class="kw-2">&</span>[u8] = <span class="kw-2">&</span>[]; |
| Bytes::from_static(EMPTY) |
| } |
| |
| <span class="doccomment">/// Creates a new `Bytes` from a static slice. |
| /// |
| /// The returned `Bytes` will point directly to the static slice. There is |
| /// no allocating or copying. |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| /// use bytes::Bytes; |
| /// |
| /// let b = Bytes::from_static(b"hello"); |
| /// assert_eq!(&b[..], b"hello"); |
| /// ``` |
| </span><span class="attribute">#[inline] |
| #[cfg(not(all(loom, test)))] |
| </span><span class="kw">pub const fn </span>from_static(bytes: <span class="kw-2">&</span><span class="lifetime">'static </span>[u8]) -> <span class="self">Self </span>{ |
| Bytes { |
| ptr: bytes.as_ptr(), |
| len: bytes.len(), |
| data: AtomicPtr::new(ptr::null_mut()), |
| vtable: <span class="kw-2">&</span>STATIC_VTABLE, |
| } |
| } |
| |
| <span class="attribute">#[cfg(all(loom, test))] |
| </span><span class="kw">pub fn </span>from_static(bytes: <span class="kw-2">&</span><span class="lifetime">'static </span>[u8]) -> <span class="self">Self </span>{ |
| Bytes { |
| ptr: bytes.as_ptr(), |
| len: bytes.len(), |
| data: AtomicPtr::new(ptr::null_mut()), |
| vtable: <span class="kw-2">&</span>STATIC_VTABLE, |
| } |
| } |
| |
| <span class="doccomment">/// Returns the number of bytes contained in this `Bytes`. |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| /// use bytes::Bytes; |
| /// |
| /// let b = Bytes::from(&b"hello"[..]); |
| /// assert_eq!(b.len(), 5); |
| /// ``` |
| </span><span class="attribute">#[inline] |
| </span><span class="kw">pub const fn </span>len(<span class="kw-2">&</span><span class="self">self</span>) -> usize { |
| <span class="self">self</span>.len |
| } |
| |
| <span class="doccomment">/// Returns true if the `Bytes` has a length of 0. |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| /// use bytes::Bytes; |
| /// |
| /// let b = Bytes::new(); |
| /// assert!(b.is_empty()); |
| /// ``` |
| </span><span class="attribute">#[inline] |
| </span><span class="kw">pub const fn </span>is_empty(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| <span class="self">self</span>.len == <span class="number">0 |
| </span>} |
| |
| <span class="doccomment">/// Creates `Bytes` instance from slice, by copying it. |
| </span><span class="kw">pub fn </span>copy_from_slice(data: <span class="kw-2">&</span>[u8]) -> <span class="self">Self </span>{ |
| data.to_vec().into() |
| } |
| |
| <span class="doccomment">/// Returns a slice of self for the provided range. |
| /// |
| /// This will increment the reference count for the underlying memory and |
| /// return a new `Bytes` handle set to the slice. |
| /// |
| /// This operation is `O(1)`. |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| /// use bytes::Bytes; |
| /// |
| /// let a = Bytes::from(&b"hello world"[..]); |
| /// let b = a.slice(2..5); |
| /// |
| /// assert_eq!(&b[..], b"llo"); |
| /// ``` |
| /// |
| /// # Panics |
| /// |
| /// Requires that `begin <= end` and `end <= self.len()`, otherwise slicing |
| /// will panic. |
| </span><span class="kw">pub fn </span>slice(<span class="kw-2">&</span><span class="self">self</span>, range: <span class="kw">impl </span>RangeBounds<usize>) -> <span class="self">Self </span>{ |
| <span class="kw">use </span>core::ops::Bound; |
| |
| <span class="kw">let </span>len = <span class="self">self</span>.len(); |
| |
| <span class="kw">let </span>begin = <span class="kw">match </span>range.start_bound() { |
| Bound::Included(<span class="kw-2">&</span>n) => n, |
| Bound::Excluded(<span class="kw-2">&</span>n) => n + <span class="number">1</span>, |
| Bound::Unbounded => <span class="number">0</span>, |
| }; |
| |
| <span class="kw">let </span>end = <span class="kw">match </span>range.end_bound() { |
| Bound::Included(<span class="kw-2">&</span>n) => n.checked_add(<span class="number">1</span>).expect(<span class="string">"out of range"</span>), |
| Bound::Excluded(<span class="kw-2">&</span>n) => n, |
| Bound::Unbounded => len, |
| }; |
| |
| <span class="macro">assert!</span>( |
| begin <= end, |
| <span class="string">"range start must not be greater than end: {:?} <= {:?}"</span>, |
| begin, |
| end, |
| ); |
| <span class="macro">assert!</span>( |
| end <= len, |
| <span class="string">"range end out of bounds: {:?} <= {:?}"</span>, |
| end, |
| len, |
| ); |
| |
| <span class="kw">if </span>end == begin { |
| <span class="kw">return </span>Bytes::new(); |
| } |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>ret = <span class="self">self</span>.clone(); |
| |
| ret.len = end - begin; |
| ret.ptr = <span class="kw">unsafe </span>{ ret.ptr.add(begin) }; |
| |
| ret |
| } |
| |
| <span class="doccomment">/// Returns a slice of self that is equivalent to the given `subset`. |
| /// |
| /// When processing a `Bytes` buffer with other tools, one often gets a |
| /// `&[u8]` which is in fact a slice of the `Bytes`, i.e. a subset of it. |
| /// This function turns that `&[u8]` into another `Bytes`, as if one had |
| /// called `self.slice()` with the offsets that correspond to `subset`. |
| /// |
| /// This operation is `O(1)`. |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| /// use bytes::Bytes; |
| /// |
| /// let bytes = Bytes::from(&b"012345678"[..]); |
| /// let as_slice = bytes.as_ref(); |
| /// let subset = &as_slice[2..6]; |
| /// let subslice = bytes.slice_ref(&subset); |
| /// assert_eq!(&subslice[..], b"2345"); |
| /// ``` |
| /// |
| /// # Panics |
| /// |
| /// Requires that the given `sub` slice is in fact contained within the |
| /// `Bytes` buffer; otherwise this function will panic. |
| </span><span class="kw">pub fn </span>slice_ref(<span class="kw-2">&</span><span class="self">self</span>, subset: <span class="kw-2">&</span>[u8]) -> <span class="self">Self </span>{ |
| <span class="comment">// Empty slice and empty Bytes may have their pointers reset |
| // so explicitly allow empty slice to be a subslice of any slice. |
| </span><span class="kw">if </span>subset.is_empty() { |
| <span class="kw">return </span>Bytes::new(); |
| } |
| |
| <span class="kw">let </span>bytes_p = <span class="self">self</span>.as_ptr() <span class="kw">as </span>usize; |
| <span class="kw">let </span>bytes_len = <span class="self">self</span>.len(); |
| |
| <span class="kw">let </span>sub_p = subset.as_ptr() <span class="kw">as </span>usize; |
| <span class="kw">let </span>sub_len = subset.len(); |
| |
| <span class="macro">assert!</span>( |
| sub_p >= bytes_p, |
| <span class="string">"subset pointer ({:p}) is smaller than self pointer ({:p})"</span>, |
| subset.as_ptr(), |
| <span class="self">self</span>.as_ptr(), |
| ); |
| <span class="macro">assert!</span>( |
| sub_p + sub_len <= bytes_p + bytes_len, |
| <span class="string">"subset is out of bounds: self = ({:p}, {}), subset = ({:p}, {})"</span>, |
| <span class="self">self</span>.as_ptr(), |
| bytes_len, |
| subset.as_ptr(), |
| sub_len, |
| ); |
| |
| <span class="kw">let </span>sub_offset = sub_p - bytes_p; |
| |
| <span class="self">self</span>.slice(sub_offset..(sub_offset + sub_len)) |
| } |
| |
| <span class="doccomment">/// Splits the bytes into two at the given index. |
| /// |
| /// Afterwards `self` contains elements `[0, at)`, and the returned `Bytes` |
| /// contains elements `[at, len)`. |
| /// |
| /// This is an `O(1)` operation that just increases the reference count and |
| /// sets a few indices. |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| /// use bytes::Bytes; |
| /// |
| /// let mut a = Bytes::from(&b"hello world"[..]); |
| /// let b = a.split_off(5); |
| /// |
| /// assert_eq!(&a[..], b"hello"); |
| /// assert_eq!(&b[..], b" world"); |
| /// ``` |
| /// |
| /// # Panics |
| /// |
| /// Panics if `at > len`. |
| </span><span class="attribute">#[must_use = <span class="string">"consider Bytes::truncate if you don't need the other half"</span>] |
| </span><span class="kw">pub fn </span>split_off(<span class="kw-2">&mut </span><span class="self">self</span>, at: usize) -> <span class="self">Self </span>{ |
| <span class="macro">assert!</span>( |
| at <= <span class="self">self</span>.len(), |
| <span class="string">"split_off out of bounds: {:?} <= {:?}"</span>, |
| at, |
| <span class="self">self</span>.len(), |
| ); |
| |
| <span class="kw">if </span>at == <span class="self">self</span>.len() { |
| <span class="kw">return </span>Bytes::new(); |
| } |
| |
| <span class="kw">if </span>at == <span class="number">0 </span>{ |
| <span class="kw">return </span>mem::replace(<span class="self">self</span>, Bytes::new()); |
| } |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>ret = <span class="self">self</span>.clone(); |
| |
| <span class="self">self</span>.len = at; |
| |
| <span class="kw">unsafe </span>{ ret.inc_start(at) }; |
| |
| ret |
| } |
| |
| <span class="doccomment">/// Splits the bytes into two at the given index. |
| /// |
| /// Afterwards `self` contains elements `[at, len)`, and the returned |
| /// `Bytes` contains elements `[0, at)`. |
| /// |
| /// This is an `O(1)` operation that just increases the reference count and |
| /// sets a few indices. |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| /// use bytes::Bytes; |
| /// |
| /// let mut a = Bytes::from(&b"hello world"[..]); |
| /// let b = a.split_to(5); |
| /// |
| /// assert_eq!(&a[..], b" world"); |
| /// assert_eq!(&b[..], b"hello"); |
| /// ``` |
| /// |
| /// # Panics |
| /// |
| /// Panics if `at > len`. |
| </span><span class="attribute">#[must_use = <span class="string">"consider Bytes::advance if you don't need the other half"</span>] |
| </span><span class="kw">pub fn </span>split_to(<span class="kw-2">&mut </span><span class="self">self</span>, at: usize) -> <span class="self">Self </span>{ |
| <span class="macro">assert!</span>( |
| at <= <span class="self">self</span>.len(), |
| <span class="string">"split_to out of bounds: {:?} <= {:?}"</span>, |
| at, |
| <span class="self">self</span>.len(), |
| ); |
| |
| <span class="kw">if </span>at == <span class="self">self</span>.len() { |
| <span class="kw">return </span>mem::replace(<span class="self">self</span>, Bytes::new()); |
| } |
| |
| <span class="kw">if </span>at == <span class="number">0 </span>{ |
| <span class="kw">return </span>Bytes::new(); |
| } |
| |
| <span class="kw">let </span><span class="kw-2">mut </span>ret = <span class="self">self</span>.clone(); |
| |
| <span class="kw">unsafe </span>{ <span class="self">self</span>.inc_start(at) }; |
| |
| ret.len = at; |
| ret |
| } |
| |
| <span class="doccomment">/// Shortens the buffer, keeping the first `len` bytes and dropping the |
| /// rest. |
| /// |
| /// If `len` is greater than the buffer's current length, this has no |
| /// effect. |
| /// |
| /// The [`split_off`] method can emulate `truncate`, but this causes the |
| /// excess bytes to be returned instead of dropped. |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| /// use bytes::Bytes; |
| /// |
| /// let mut buf = Bytes::from(&b"hello world"[..]); |
| /// buf.truncate(5); |
| /// assert_eq!(buf, b"hello"[..]); |
| /// ``` |
| /// |
| /// [`split_off`]: #method.split_off |
| </span><span class="attribute">#[inline] |
| </span><span class="kw">pub fn </span>truncate(<span class="kw-2">&mut </span><span class="self">self</span>, len: usize) { |
| <span class="kw">if </span>len < <span class="self">self</span>.len { |
| <span class="comment">// The Vec "promotable" vtables do not store the capacity, |
| // so we cannot truncate while using this repr. We *have* to |
| // promote using `split_off` so the capacity can be stored. |
| </span><span class="kw">if </span><span class="self">self</span>.vtable <span class="kw">as </span><span class="kw-2">*const </span>Vtable == <span class="kw-2">&</span>PROMOTABLE_EVEN_VTABLE |
| || <span class="self">self</span>.vtable <span class="kw">as </span><span class="kw-2">*const </span>Vtable == <span class="kw-2">&</span>PROMOTABLE_ODD_VTABLE |
| { |
| drop(<span class="self">self</span>.split_off(len)); |
| } <span class="kw">else </span>{ |
| <span class="self">self</span>.len = len; |
| } |
| } |
| } |
| |
| <span class="doccomment">/// Clears the buffer, removing all data. |
| /// |
| /// # Examples |
| /// |
| /// ``` |
| /// use bytes::Bytes; |
| /// |
| /// let mut buf = Bytes::from(&b"hello world"[..]); |
| /// buf.clear(); |
| /// assert!(buf.is_empty()); |
| /// ``` |
| </span><span class="attribute">#[inline] |
| </span><span class="kw">pub fn </span>clear(<span class="kw-2">&mut </span><span class="self">self</span>) { |
| <span class="self">self</span>.truncate(<span class="number">0</span>); |
| } |
| |
| <span class="attribute">#[inline] |
| </span><span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">unsafe fn </span>with_vtable( |
| ptr: <span class="kw-2">*const </span>u8, |
| len: usize, |
| data: AtomicPtr<()>, |
| vtable: <span class="kw-2">&</span><span class="lifetime">'static </span>Vtable, |
| ) -> Bytes { |
| Bytes { |
| ptr, |
| len, |
| data, |
| vtable, |
| } |
| } |
| |
| <span class="comment">// private |
| |
| </span><span class="attribute">#[inline] |
| </span><span class="kw">fn </span>as_slice(<span class="kw-2">&</span><span class="self">self</span>) -> <span class="kw-2">&</span>[u8] { |
| <span class="kw">unsafe </span>{ slice::from_raw_parts(<span class="self">self</span>.ptr, <span class="self">self</span>.len) } |
| } |
| |
| <span class="attribute">#[inline] |
| </span><span class="kw">unsafe fn </span>inc_start(<span class="kw-2">&mut </span><span class="self">self</span>, by: usize) { |
| <span class="comment">// should already be asserted, but debug assert for tests |
| </span><span class="macro">debug_assert!</span>(<span class="self">self</span>.len >= by, <span class="string">"internal: inc_start out of bounds"</span>); |
| <span class="self">self</span>.len -= by; |
| <span class="self">self</span>.ptr = <span class="self">self</span>.ptr.add(by); |
| } |
| } |
| |
| <span class="comment">// Vtable must enforce this behavior |
| </span><span class="kw">unsafe impl </span>Send <span class="kw">for </span>Bytes {} |
| <span class="kw">unsafe impl </span>Sync <span class="kw">for </span>Bytes {} |
| |
| <span class="kw">impl </span>Drop <span class="kw">for </span>Bytes { |
| <span class="attribute">#[inline] |
| </span><span class="kw">fn </span>drop(<span class="kw-2">&mut </span><span class="self">self</span>) { |
| <span class="kw">unsafe </span>{ (<span class="self">self</span>.vtable.drop)(<span class="kw-2">&mut </span><span class="self">self</span>.data, <span class="self">self</span>.ptr, <span class="self">self</span>.len) } |
| } |
| } |
| |
| <span class="kw">impl </span>Clone <span class="kw">for </span>Bytes { |
| <span class="attribute">#[inline] |
| </span><span class="kw">fn </span>clone(<span class="kw-2">&</span><span class="self">self</span>) -> Bytes { |
| <span class="kw">unsafe </span>{ (<span class="self">self</span>.vtable.clone)(<span class="kw-2">&</span><span class="self">self</span>.data, <span class="self">self</span>.ptr, <span class="self">self</span>.len) } |
| } |
| } |
| |
| <span class="kw">impl </span>Buf <span class="kw">for </span>Bytes { |
| <span class="attribute">#[inline] |
| </span><span class="kw">fn </span>remaining(<span class="kw-2">&</span><span class="self">self</span>) -> usize { |
| <span class="self">self</span>.len() |
| } |
| |
| <span class="attribute">#[inline] |
| </span><span class="kw">fn </span>chunk(<span class="kw-2">&</span><span class="self">self</span>) -> <span class="kw-2">&</span>[u8] { |
| <span class="self">self</span>.as_slice() |
| } |
| |
| <span class="attribute">#[inline] |
| </span><span class="kw">fn </span>advance(<span class="kw-2">&mut </span><span class="self">self</span>, cnt: usize) { |
| <span class="macro">assert!</span>( |
| cnt <= <span class="self">self</span>.len(), |
| <span class="string">"cannot advance past `remaining`: {:?} <= {:?}"</span>, |
| cnt, |
| <span class="self">self</span>.len(), |
| ); |
| |
| <span class="kw">unsafe </span>{ |
| <span class="self">self</span>.inc_start(cnt); |
| } |
| } |
| |
| <span class="kw">fn </span>copy_to_bytes(<span class="kw-2">&mut </span><span class="self">self</span>, len: usize) -> <span class="kw">crate</span>::Bytes { |
| <span class="kw">if </span>len == <span class="self">self</span>.remaining() { |
| core::mem::replace(<span class="self">self</span>, Bytes::new()) |
| } <span class="kw">else </span>{ |
| <span class="kw">let </span>ret = <span class="self">self</span>.slice(..len); |
| <span class="self">self</span>.advance(len); |
| ret |
| } |
| } |
| } |
| |
| <span class="kw">impl </span>Deref <span class="kw">for </span>Bytes { |
| <span class="kw">type </span>Target = [u8]; |
| |
| <span class="attribute">#[inline] |
| </span><span class="kw">fn </span>deref(<span class="kw-2">&</span><span class="self">self</span>) -> <span class="kw-2">&</span>[u8] { |
| <span class="self">self</span>.as_slice() |
| } |
| } |
| |
| <span class="kw">impl </span>AsRef<[u8]> <span class="kw">for </span>Bytes { |
| <span class="attribute">#[inline] |
| </span><span class="kw">fn </span>as_ref(<span class="kw-2">&</span><span class="self">self</span>) -> <span class="kw-2">&</span>[u8] { |
| <span class="self">self</span>.as_slice() |
| } |
| } |
| |
| <span class="kw">impl </span>hash::Hash <span class="kw">for </span>Bytes { |
| <span class="kw">fn </span>hash<H>(<span class="kw-2">&</span><span class="self">self</span>, state: <span class="kw-2">&mut </span>H) |
| <span class="kw">where |
| </span>H: hash::Hasher, |
| { |
| <span class="self">self</span>.as_slice().hash(state); |
| } |
| } |
| |
| <span class="kw">impl </span>Borrow<[u8]> <span class="kw">for </span>Bytes { |
| <span class="kw">fn </span>borrow(<span class="kw-2">&</span><span class="self">self</span>) -> <span class="kw-2">&</span>[u8] { |
| <span class="self">self</span>.as_slice() |
| } |
| } |
| |
| <span class="kw">impl </span>IntoIterator <span class="kw">for </span>Bytes { |
| <span class="kw">type </span>Item = u8; |
| <span class="kw">type </span>IntoIter = IntoIter<Bytes>; |
| |
| <span class="kw">fn </span>into_iter(<span class="self">self</span>) -> <span class="self">Self</span>::IntoIter { |
| IntoIter::new(<span class="self">self</span>) |
| } |
| } |
| |
| <span class="kw">impl</span><<span class="lifetime">'a</span>> IntoIterator <span class="kw">for </span><span class="kw-2">&</span><span class="lifetime">'a </span>Bytes { |
| <span class="kw">type </span>Item = <span class="kw-2">&</span><span class="lifetime">'a </span>u8; |
| <span class="kw">type </span>IntoIter = core::slice::Iter<<span class="lifetime">'a</span>, u8>; |
| |
| <span class="kw">fn </span>into_iter(<span class="self">self</span>) -> <span class="self">Self</span>::IntoIter { |
| <span class="self">self</span>.as_slice().iter() |
| } |
| } |
| |
| <span class="kw">impl </span>FromIterator<u8> <span class="kw">for </span>Bytes { |
| <span class="kw">fn </span>from_iter<T: IntoIterator<Item = u8>>(into_iter: T) -> <span class="self">Self </span>{ |
| Vec::from_iter(into_iter).into() |
| } |
| } |
| |
| <span class="comment">// impl Eq |
| |
| </span><span class="kw">impl </span>PartialEq <span class="kw">for </span>Bytes { |
| <span class="kw">fn </span>eq(<span class="kw-2">&</span><span class="self">self</span>, other: <span class="kw-2">&</span>Bytes) -> bool { |
| <span class="self">self</span>.as_slice() == other.as_slice() |
| } |
| } |
| |
| <span class="kw">impl </span>PartialOrd <span class="kw">for </span>Bytes { |
| <span class="kw">fn </span>partial_cmp(<span class="kw-2">&</span><span class="self">self</span>, other: <span class="kw-2">&</span>Bytes) -> <span class="prelude-ty">Option</span><cmp::Ordering> { |
| <span class="self">self</span>.as_slice().partial_cmp(other.as_slice()) |
| } |
| } |
| |
| <span class="kw">impl </span>Ord <span class="kw">for </span>Bytes { |
| <span class="kw">fn </span>cmp(<span class="kw-2">&</span><span class="self">self</span>, other: <span class="kw-2">&</span>Bytes) -> cmp::Ordering { |
| <span class="self">self</span>.as_slice().cmp(other.as_slice()) |
| } |
| } |
| |
| <span class="kw">impl </span>Eq <span class="kw">for </span>Bytes {} |
| |
| <span class="kw">impl </span>PartialEq<[u8]> <span class="kw">for </span>Bytes { |
| <span class="kw">fn </span>eq(<span class="kw-2">&</span><span class="self">self</span>, other: <span class="kw-2">&</span>[u8]) -> bool { |
| <span class="self">self</span>.as_slice() == other |
| } |
| } |
| |
| <span class="kw">impl </span>PartialOrd<[u8]> <span class="kw">for </span>Bytes { |
| <span class="kw">fn </span>partial_cmp(<span class="kw-2">&</span><span class="self">self</span>, other: <span class="kw-2">&</span>[u8]) -> <span class="prelude-ty">Option</span><cmp::Ordering> { |
| <span class="self">self</span>.as_slice().partial_cmp(other) |
| } |
| } |
| |
| <span class="kw">impl </span>PartialEq<Bytes> <span class="kw">for </span>[u8] { |
| <span class="kw">fn </span>eq(<span class="kw-2">&</span><span class="self">self</span>, other: <span class="kw-2">&</span>Bytes) -> bool { |
| <span class="kw-2">*</span>other == <span class="kw-2">*</span><span class="self">self |
| </span>} |
| } |
| |
| <span class="kw">impl </span>PartialOrd<Bytes> <span class="kw">for </span>[u8] { |
| <span class="kw">fn </span>partial_cmp(<span class="kw-2">&</span><span class="self">self</span>, other: <span class="kw-2">&</span>Bytes) -> <span class="prelude-ty">Option</span><cmp::Ordering> { |
| <[u8] <span class="kw">as </span>PartialOrd<[u8]>>::partial_cmp(<span class="self">self</span>, other) |
| } |
| } |
| |
| <span class="kw">impl </span>PartialEq<str> <span class="kw">for </span>Bytes { |
| <span class="kw">fn </span>eq(<span class="kw-2">&</span><span class="self">self</span>, other: <span class="kw-2">&</span>str) -> bool { |
| <span class="self">self</span>.as_slice() == other.as_bytes() |
| } |
| } |
| |
| <span class="kw">impl </span>PartialOrd<str> <span class="kw">for </span>Bytes { |
| <span class="kw">fn </span>partial_cmp(<span class="kw-2">&</span><span class="self">self</span>, other: <span class="kw-2">&</span>str) -> <span class="prelude-ty">Option</span><cmp::Ordering> { |
| <span class="self">self</span>.as_slice().partial_cmp(other.as_bytes()) |
| } |
| } |
| |
| <span class="kw">impl </span>PartialEq<Bytes> <span class="kw">for </span>str { |
| <span class="kw">fn </span>eq(<span class="kw-2">&</span><span class="self">self</span>, other: <span class="kw-2">&</span>Bytes) -> bool { |
| <span class="kw-2">*</span>other == <span class="kw-2">*</span><span class="self">self |
| </span>} |
| } |
| |
| <span class="kw">impl </span>PartialOrd<Bytes> <span class="kw">for </span>str { |
| <span class="kw">fn </span>partial_cmp(<span class="kw-2">&</span><span class="self">self</span>, other: <span class="kw-2">&</span>Bytes) -> <span class="prelude-ty">Option</span><cmp::Ordering> { |
| <[u8] <span class="kw">as </span>PartialOrd<[u8]>>::partial_cmp(<span class="self">self</span>.as_bytes(), other) |
| } |
| } |
| |
| <span class="kw">impl </span>PartialEq<Vec<u8>> <span class="kw">for </span>Bytes { |
| <span class="kw">fn </span>eq(<span class="kw-2">&</span><span class="self">self</span>, other: <span class="kw-2">&</span>Vec<u8>) -> bool { |
| <span class="kw-2">*</span><span class="self">self </span>== other[..] |
| } |
| } |
| |
| <span class="kw">impl </span>PartialOrd<Vec<u8>> <span class="kw">for </span>Bytes { |
| <span class="kw">fn </span>partial_cmp(<span class="kw-2">&</span><span class="self">self</span>, other: <span class="kw-2">&</span>Vec<u8>) -> <span class="prelude-ty">Option</span><cmp::Ordering> { |
| <span class="self">self</span>.as_slice().partial_cmp(<span class="kw-2">&</span>other[..]) |
| } |
| } |
| |
| <span class="kw">impl </span>PartialEq<Bytes> <span class="kw">for </span>Vec<u8> { |
| <span class="kw">fn </span>eq(<span class="kw-2">&</span><span class="self">self</span>, other: <span class="kw-2">&</span>Bytes) -> bool { |
| <span class="kw-2">*</span>other == <span class="kw-2">*</span><span class="self">self |
| </span>} |
| } |
| |
| <span class="kw">impl </span>PartialOrd<Bytes> <span class="kw">for </span>Vec<u8> { |
| <span class="kw">fn </span>partial_cmp(<span class="kw-2">&</span><span class="self">self</span>, other: <span class="kw-2">&</span>Bytes) -> <span class="prelude-ty">Option</span><cmp::Ordering> { |
| <[u8] <span class="kw">as </span>PartialOrd<[u8]>>::partial_cmp(<span class="self">self</span>, other) |
| } |
| } |
| |
| <span class="kw">impl </span>PartialEq<String> <span class="kw">for </span>Bytes { |
| <span class="kw">fn </span>eq(<span class="kw-2">&</span><span class="self">self</span>, other: <span class="kw-2">&</span>String) -> bool { |
| <span class="kw-2">*</span><span class="self">self </span>== other[..] |
| } |
| } |
| |
| <span class="kw">impl </span>PartialOrd<String> <span class="kw">for </span>Bytes { |
| <span class="kw">fn </span>partial_cmp(<span class="kw-2">&</span><span class="self">self</span>, other: <span class="kw-2">&</span>String) -> <span class="prelude-ty">Option</span><cmp::Ordering> { |
| <span class="self">self</span>.as_slice().partial_cmp(other.as_bytes()) |
| } |
| } |
| |
| <span class="kw">impl </span>PartialEq<Bytes> <span class="kw">for </span>String { |
| <span class="kw">fn </span>eq(<span class="kw-2">&</span><span class="self">self</span>, other: <span class="kw-2">&</span>Bytes) -> bool { |
| <span class="kw-2">*</span>other == <span class="kw-2">*</span><span class="self">self |
| </span>} |
| } |
| |
| <span class="kw">impl </span>PartialOrd<Bytes> <span class="kw">for </span>String { |
| <span class="kw">fn </span>partial_cmp(<span class="kw-2">&</span><span class="self">self</span>, other: <span class="kw-2">&</span>Bytes) -> <span class="prelude-ty">Option</span><cmp::Ordering> { |
| <[u8] <span class="kw">as </span>PartialOrd<[u8]>>::partial_cmp(<span class="self">self</span>.as_bytes(), other) |
| } |
| } |
| |
| <span class="kw">impl </span>PartialEq<Bytes> <span class="kw">for </span><span class="kw-2">&</span>[u8] { |
| <span class="kw">fn </span>eq(<span class="kw-2">&</span><span class="self">self</span>, other: <span class="kw-2">&</span>Bytes) -> bool { |
| <span class="kw-2">*</span>other == <span class="kw-2">*</span><span class="self">self |
| </span>} |
| } |
| |
| <span class="kw">impl </span>PartialOrd<Bytes> <span class="kw">for </span><span class="kw-2">&</span>[u8] { |
| <span class="kw">fn </span>partial_cmp(<span class="kw-2">&</span><span class="self">self</span>, other: <span class="kw-2">&</span>Bytes) -> <span class="prelude-ty">Option</span><cmp::Ordering> { |
| <[u8] <span class="kw">as </span>PartialOrd<[u8]>>::partial_cmp(<span class="self">self</span>, other) |
| } |
| } |
| |
| <span class="kw">impl </span>PartialEq<Bytes> <span class="kw">for </span><span class="kw-2">&</span>str { |
| <span class="kw">fn </span>eq(<span class="kw-2">&</span><span class="self">self</span>, other: <span class="kw-2">&</span>Bytes) -> bool { |
| <span class="kw-2">*</span>other == <span class="kw-2">*</span><span class="self">self |
| </span>} |
| } |
| |
| <span class="kw">impl </span>PartialOrd<Bytes> <span class="kw">for </span><span class="kw-2">&</span>str { |
| <span class="kw">fn </span>partial_cmp(<span class="kw-2">&</span><span class="self">self</span>, other: <span class="kw-2">&</span>Bytes) -> <span class="prelude-ty">Option</span><cmp::Ordering> { |
| <[u8] <span class="kw">as </span>PartialOrd<[u8]>>::partial_cmp(<span class="self">self</span>.as_bytes(), other) |
| } |
| } |
| |
| <span class="kw">impl</span><<span class="lifetime">'a</span>, T: <span class="question-mark">?</span>Sized> PartialEq<<span class="kw-2">&</span><span class="lifetime">'a </span>T> <span class="kw">for </span>Bytes |
| <span class="kw">where |
| </span>Bytes: PartialEq<T>, |
| { |
| <span class="kw">fn </span>eq(<span class="kw-2">&</span><span class="self">self</span>, other: &&<span class="lifetime">'a </span>T) -> bool { |
| <span class="kw-2">*</span><span class="self">self </span>== <span class="kw-2">**</span>other |
| } |
| } |
| |
| <span class="kw">impl</span><<span class="lifetime">'a</span>, T: <span class="question-mark">?</span>Sized> PartialOrd<<span class="kw-2">&</span><span class="lifetime">'a </span>T> <span class="kw">for </span>Bytes |
| <span class="kw">where |
| </span>Bytes: PartialOrd<T>, |
| { |
| <span class="kw">fn </span>partial_cmp(<span class="kw-2">&</span><span class="self">self</span>, other: &&<span class="lifetime">'a </span>T) -> <span class="prelude-ty">Option</span><cmp::Ordering> { |
| <span class="self">self</span>.partial_cmp(<span class="kw-2">&**</span>other) |
| } |
| } |
| |
| <span class="comment">// impl From |
| |
| </span><span class="kw">impl </span>Default <span class="kw">for </span>Bytes { |
| <span class="attribute">#[inline] |
| </span><span class="kw">fn </span>default() -> Bytes { |
| Bytes::new() |
| } |
| } |
| |
| <span class="kw">impl </span>From<<span class="kw-2">&</span><span class="lifetime">'static </span>[u8]> <span class="kw">for </span>Bytes { |
| <span class="kw">fn </span>from(slice: <span class="kw-2">&</span><span class="lifetime">'static </span>[u8]) -> Bytes { |
| Bytes::from_static(slice) |
| } |
| } |
| |
| <span class="kw">impl </span>From<<span class="kw-2">&</span><span class="lifetime">'static </span>str> <span class="kw">for </span>Bytes { |
| <span class="kw">fn </span>from(slice: <span class="kw-2">&</span><span class="lifetime">'static </span>str) -> Bytes { |
| Bytes::from_static(slice.as_bytes()) |
| } |
| } |
| |
| <span class="kw">impl </span>From<Vec<u8>> <span class="kw">for </span>Bytes { |
| <span class="kw">fn </span>from(vec: Vec<u8>) -> Bytes { |
| <span class="kw">let </span><span class="kw-2">mut </span>vec = vec; |
| <span class="kw">let </span>ptr = vec.as_mut_ptr(); |
| <span class="kw">let </span>len = vec.len(); |
| <span class="kw">let </span>cap = vec.capacity(); |
| |
| <span class="comment">// Avoid an extra allocation if possible. |
| </span><span class="kw">if </span>len == cap { |
| <span class="kw">return </span>Bytes::from(vec.into_boxed_slice()); |
| } |
| |
| <span class="kw">let </span>shared = Box::new(Shared { |
| buf: ptr, |
| cap, |
| ref_cnt: AtomicUsize::new(<span class="number">1</span>), |
| }); |
| mem::forget(vec); |
| |
| <span class="kw">let </span>shared = Box::into_raw(shared); |
| <span class="comment">// The pointer should be aligned, so this assert should |
| // always succeed. |
| </span><span class="macro">debug_assert!</span>( |
| <span class="number">0 </span>== (shared <span class="kw">as </span>usize & KIND_MASK), |
| <span class="string">"internal: Box<Shared> should have an aligned pointer"</span>, |
| ); |
| Bytes { |
| ptr, |
| len, |
| data: AtomicPtr::new(shared <span class="kw">as _</span>), |
| vtable: <span class="kw-2">&</span>SHARED_VTABLE, |
| } |
| } |
| } |
| |
| <span class="kw">impl </span>From<Box<[u8]>> <span class="kw">for </span>Bytes { |
| <span class="kw">fn </span>from(slice: Box<[u8]>) -> Bytes { |
| <span class="comment">// Box<[u8]> doesn't contain a heap allocation for empty slices, |
| // so the pointer isn't aligned enough for the KIND_VEC stashing to |
| // work. |
| </span><span class="kw">if </span>slice.is_empty() { |
| <span class="kw">return </span>Bytes::new(); |
| } |
| |
| <span class="kw">let </span>len = slice.len(); |
| <span class="kw">let </span>ptr = Box::into_raw(slice) <span class="kw">as </span><span class="kw-2">*mut </span>u8; |
| |
| <span class="kw">if </span>ptr <span class="kw">as </span>usize & <span class="number">0x1 </span>== <span class="number">0 </span>{ |
| <span class="kw">let </span>data = ptr_map(ptr, |addr| addr | KIND_VEC); |
| Bytes { |
| ptr, |
| len, |
| data: AtomicPtr::new(data.cast()), |
| vtable: <span class="kw-2">&</span>PROMOTABLE_EVEN_VTABLE, |
| } |
| } <span class="kw">else </span>{ |
| Bytes { |
| ptr, |
| len, |
| data: AtomicPtr::new(ptr.cast()), |
| vtable: <span class="kw-2">&</span>PROMOTABLE_ODD_VTABLE, |
| } |
| } |
| } |
| } |
| |
| <span class="kw">impl </span>From<String> <span class="kw">for </span>Bytes { |
| <span class="kw">fn </span>from(s: String) -> Bytes { |
| Bytes::from(s.into_bytes()) |
| } |
| } |
| |
| <span class="kw">impl </span>From<Bytes> <span class="kw">for </span>Vec<u8> { |
| <span class="kw">fn </span>from(bytes: Bytes) -> Vec<u8> { |
| <span class="kw">let </span>bytes = mem::ManuallyDrop::new(bytes); |
| <span class="kw">unsafe </span>{ (bytes.vtable.to_vec)(<span class="kw-2">&</span>bytes.data, bytes.ptr, bytes.len) } |
| } |
| } |
| |
| <span class="comment">// ===== impl Vtable ===== |
| |
| </span><span class="kw">impl </span>fmt::Debug <span class="kw">for </span>Vtable { |
| <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<<span class="lifetime">'_</span>>) -> fmt::Result { |
| f.debug_struct(<span class="string">"Vtable"</span>) |
| .field(<span class="string">"clone"</span>, <span class="kw-2">&</span>(<span class="self">self</span>.clone <span class="kw">as </span><span class="kw-2">*const </span>())) |
| .field(<span class="string">"drop"</span>, <span class="kw-2">&</span>(<span class="self">self</span>.drop <span class="kw">as </span><span class="kw-2">*const </span>())) |
| .finish() |
| } |
| } |
| |
| <span class="comment">// ===== impl StaticVtable ===== |
| |
| </span><span class="kw">const </span>STATIC_VTABLE: Vtable = Vtable { |
| clone: static_clone, |
| to_vec: static_to_vec, |
| drop: static_drop, |
| }; |
| |
| <span class="kw">unsafe fn </span>static_clone(<span class="kw">_</span>: <span class="kw-2">&</span>AtomicPtr<()>, ptr: <span class="kw-2">*const </span>u8, len: usize) -> Bytes { |
| <span class="kw">let </span>slice = slice::from_raw_parts(ptr, len); |
| Bytes::from_static(slice) |
| } |
| |
| <span class="kw">unsafe fn </span>static_to_vec(<span class="kw">_</span>: <span class="kw-2">&</span>AtomicPtr<()>, ptr: <span class="kw-2">*const </span>u8, len: usize) -> Vec<u8> { |
| <span class="kw">let </span>slice = slice::from_raw_parts(ptr, len); |
| slice.to_vec() |
| } |
| |
| <span class="kw">unsafe fn </span>static_drop(<span class="kw">_</span>: <span class="kw-2">&mut </span>AtomicPtr<()>, <span class="kw">_</span>: <span class="kw-2">*const </span>u8, <span class="kw">_</span>: usize) { |
| <span class="comment">// nothing to drop for &'static [u8] |
| </span>} |
| |
| <span class="comment">// ===== impl PromotableVtable ===== |
| |
| </span><span class="kw">static </span>PROMOTABLE_EVEN_VTABLE: Vtable = Vtable { |
| clone: promotable_even_clone, |
| to_vec: promotable_even_to_vec, |
| drop: promotable_even_drop, |
| }; |
| |
| <span class="kw">static </span>PROMOTABLE_ODD_VTABLE: Vtable = Vtable { |
| clone: promotable_odd_clone, |
| to_vec: promotable_odd_to_vec, |
| drop: promotable_odd_drop, |
| }; |
| |
| <span class="kw">unsafe fn </span>promotable_even_clone(data: <span class="kw-2">&</span>AtomicPtr<()>, ptr: <span class="kw-2">*const </span>u8, len: usize) -> Bytes { |
| <span class="kw">let </span>shared = data.load(Ordering::Acquire); |
| <span class="kw">let </span>kind = shared <span class="kw">as </span>usize & KIND_MASK; |
| |
| <span class="kw">if </span>kind == KIND_ARC { |
| shallow_clone_arc(shared.cast(), ptr, len) |
| } <span class="kw">else </span>{ |
| <span class="macro">debug_assert_eq!</span>(kind, KIND_VEC); |
| <span class="kw">let </span>buf = ptr_map(shared.cast(), |addr| addr & !KIND_MASK); |
| shallow_clone_vec(data, shared, buf, ptr, len) |
| } |
| } |
| |
| <span class="kw">unsafe fn </span>promotable_to_vec( |
| data: <span class="kw-2">&</span>AtomicPtr<()>, |
| ptr: <span class="kw-2">*const </span>u8, |
| len: usize, |
| f: <span class="kw">fn</span>(<span class="kw-2">*mut </span>()) -> <span class="kw-2">*mut </span>u8, |
| ) -> Vec<u8> { |
| <span class="kw">let </span>shared = data.load(Ordering::Acquire); |
| <span class="kw">let </span>kind = shared <span class="kw">as </span>usize & KIND_MASK; |
| |
| <span class="kw">if </span>kind == KIND_ARC { |
| shared_to_vec_impl(shared.cast(), ptr, len) |
| } <span class="kw">else </span>{ |
| <span class="comment">// If Bytes holds a Vec, then the offset must be 0. |
| </span><span class="macro">debug_assert_eq!</span>(kind, KIND_VEC); |
| |
| <span class="kw">let </span>buf = f(shared); |
| |
| <span class="kw">let </span>cap = (ptr <span class="kw">as </span>usize - buf <span class="kw">as </span>usize) + len; |
| |
| <span class="comment">// Copy back buffer |
| </span>ptr::copy(ptr, buf, len); |
| |
| Vec::from_raw_parts(buf, len, cap) |
| } |
| } |
| |
| <span class="kw">unsafe fn </span>promotable_even_to_vec(data: <span class="kw-2">&</span>AtomicPtr<()>, ptr: <span class="kw-2">*const </span>u8, len: usize) -> Vec<u8> { |
| promotable_to_vec(data, ptr, len, |shared| { |
| ptr_map(shared.cast(), |addr| addr & !KIND_MASK) |
| }) |
| } |
| |
| <span class="kw">unsafe fn </span>promotable_even_drop(data: <span class="kw-2">&mut </span>AtomicPtr<()>, ptr: <span class="kw-2">*const </span>u8, len: usize) { |
| data.with_mut(|shared| { |
| <span class="kw">let </span>shared = <span class="kw-2">*</span>shared; |
| <span class="kw">let </span>kind = shared <span class="kw">as </span>usize & KIND_MASK; |
| |
| <span class="kw">if </span>kind == KIND_ARC { |
| release_shared(shared.cast()); |
| } <span class="kw">else </span>{ |
| <span class="macro">debug_assert_eq!</span>(kind, KIND_VEC); |
| <span class="kw">let </span>buf = ptr_map(shared.cast(), |addr| addr & !KIND_MASK); |
| free_boxed_slice(buf, ptr, len); |
| } |
| }); |
| } |
| |
| <span class="kw">unsafe fn </span>promotable_odd_clone(data: <span class="kw-2">&</span>AtomicPtr<()>, ptr: <span class="kw-2">*const </span>u8, len: usize) -> Bytes { |
| <span class="kw">let </span>shared = data.load(Ordering::Acquire); |
| <span class="kw">let </span>kind = shared <span class="kw">as </span>usize & KIND_MASK; |
| |
| <span class="kw">if </span>kind == KIND_ARC { |
| shallow_clone_arc(shared <span class="kw">as _</span>, ptr, len) |
| } <span class="kw">else </span>{ |
| <span class="macro">debug_assert_eq!</span>(kind, KIND_VEC); |
| shallow_clone_vec(data, shared, shared.cast(), ptr, len) |
| } |
| } |
| |
| <span class="kw">unsafe fn </span>promotable_odd_to_vec(data: <span class="kw-2">&</span>AtomicPtr<()>, ptr: <span class="kw-2">*const </span>u8, len: usize) -> Vec<u8> { |
| promotable_to_vec(data, ptr, len, |shared| shared.cast()) |
| } |
| |
| <span class="kw">unsafe fn </span>promotable_odd_drop(data: <span class="kw-2">&mut </span>AtomicPtr<()>, ptr: <span class="kw-2">*const </span>u8, len: usize) { |
| data.with_mut(|shared| { |
| <span class="kw">let </span>shared = <span class="kw-2">*</span>shared; |
| <span class="kw">let </span>kind = shared <span class="kw">as </span>usize & KIND_MASK; |
| |
| <span class="kw">if </span>kind == KIND_ARC { |
| release_shared(shared.cast()); |
| } <span class="kw">else </span>{ |
| <span class="macro">debug_assert_eq!</span>(kind, KIND_VEC); |
| |
| free_boxed_slice(shared.cast(), ptr, len); |
| } |
| }); |
| } |
| |
| <span class="kw">unsafe fn </span>free_boxed_slice(buf: <span class="kw-2">*mut </span>u8, offset: <span class="kw-2">*const </span>u8, len: usize) { |
| <span class="kw">let </span>cap = (offset <span class="kw">as </span>usize - buf <span class="kw">as </span>usize) + len; |
| dealloc(buf, Layout::from_size_align(cap, <span class="number">1</span>).unwrap()) |
| } |
| |
| <span class="comment">// ===== impl SharedVtable ===== |
| |
| </span><span class="kw">struct </span>Shared { |
| <span class="comment">// Holds arguments to dealloc upon Drop, but otherwise doesn't use them |
| </span>buf: <span class="kw-2">*mut </span>u8, |
| cap: usize, |
| ref_cnt: AtomicUsize, |
| } |
| |
| <span class="kw">impl </span>Drop <span class="kw">for </span>Shared { |
| <span class="kw">fn </span>drop(<span class="kw-2">&mut </span><span class="self">self</span>) { |
| <span class="kw">unsafe </span>{ dealloc(<span class="self">self</span>.buf, Layout::from_size_align(<span class="self">self</span>.cap, <span class="number">1</span>).unwrap()) } |
| } |
| } |
| |
| <span class="comment">// Assert that the alignment of `Shared` is divisible by 2. |
| // This is a necessary invariant since we depend on allocating `Shared` a |
| // shared object to implicitly carry the `KIND_ARC` flag in its pointer. |
| // This flag is set when the LSB is 0. |
| </span><span class="kw">const _</span>: [(); <span class="number">0 </span>- mem::align_of::<Shared>() % <span class="number">2</span>] = []; <span class="comment">// Assert that the alignment of `Shared` is divisible by 2. |
| |
| </span><span class="kw">static </span>SHARED_VTABLE: Vtable = Vtable { |
| clone: shared_clone, |
| to_vec: shared_to_vec, |
| drop: shared_drop, |
| }; |
| |
| <span class="kw">const </span>KIND_ARC: usize = <span class="number">0b0</span>; |
| <span class="kw">const </span>KIND_VEC: usize = <span class="number">0b1</span>; |
| <span class="kw">const </span>KIND_MASK: usize = <span class="number">0b1</span>; |
| |
| <span class="kw">unsafe fn </span>shared_clone(data: <span class="kw-2">&</span>AtomicPtr<()>, ptr: <span class="kw-2">*const </span>u8, len: usize) -> Bytes { |
| <span class="kw">let </span>shared = data.load(Ordering::Relaxed); |
| shallow_clone_arc(shared <span class="kw">as _</span>, ptr, len) |
| } |
| |
| <span class="kw">unsafe fn </span>shared_to_vec_impl(shared: <span class="kw-2">*mut </span>Shared, ptr: <span class="kw-2">*const </span>u8, len: usize) -> Vec<u8> { |
| <span class="comment">// Check that the ref_cnt is 1 (unique). |
| // |
| // If it is unique, then it is set to 0 with AcqRel fence for the same |
| // reason in release_shared. |
| // |
| // Otherwise, we take the other branch and call release_shared. |
| </span><span class="kw">if </span>(<span class="kw-2">*</span>shared) |
| .ref_cnt |
| .compare_exchange(<span class="number">1</span>, <span class="number">0</span>, Ordering::AcqRel, Ordering::Relaxed) |
| .is_ok() |
| { |
| <span class="kw">let </span>buf = (<span class="kw-2">*</span>shared).buf; |
| <span class="kw">let </span>cap = (<span class="kw-2">*</span>shared).cap; |
| |
| <span class="comment">// Deallocate Shared |
| </span>drop(Box::from_raw(shared <span class="kw">as </span><span class="kw-2">*mut </span>mem::ManuallyDrop<Shared>)); |
| |
| <span class="comment">// Copy back buffer |
| </span>ptr::copy(ptr, buf, len); |
| |
| Vec::from_raw_parts(buf, len, cap) |
| } <span class="kw">else </span>{ |
| <span class="kw">let </span>v = slice::from_raw_parts(ptr, len).to_vec(); |
| release_shared(shared); |
| v |
| } |
| } |
| |
| <span class="kw">unsafe fn </span>shared_to_vec(data: <span class="kw-2">&</span>AtomicPtr<()>, ptr: <span class="kw-2">*const </span>u8, len: usize) -> Vec<u8> { |
| shared_to_vec_impl(data.load(Ordering::Relaxed).cast(), ptr, len) |
| } |
| |
| <span class="kw">unsafe fn </span>shared_drop(data: <span class="kw-2">&mut </span>AtomicPtr<()>, _ptr: <span class="kw-2">*const </span>u8, _len: usize) { |
| data.with_mut(|shared| { |
| release_shared(shared.cast()); |
| }); |
| } |
| |
| <span class="kw">unsafe fn </span>shallow_clone_arc(shared: <span class="kw-2">*mut </span>Shared, ptr: <span class="kw-2">*const </span>u8, len: usize) -> Bytes { |
| <span class="kw">let </span>old_size = (<span class="kw-2">*</span>shared).ref_cnt.fetch_add(<span class="number">1</span>, Ordering::Relaxed); |
| |
| <span class="kw">if </span>old_size > usize::MAX >> <span class="number">1 </span>{ |
| <span class="kw">crate</span>::abort(); |
| } |
| |
| Bytes { |
| ptr, |
| len, |
| data: AtomicPtr::new(shared <span class="kw">as _</span>), |
| vtable: <span class="kw-2">&</span>SHARED_VTABLE, |
| } |
| } |
| |
| <span class="attribute">#[cold] |
| </span><span class="kw">unsafe fn </span>shallow_clone_vec( |
| atom: <span class="kw-2">&</span>AtomicPtr<()>, |
| ptr: <span class="kw-2">*const </span>(), |
| buf: <span class="kw-2">*mut </span>u8, |
| offset: <span class="kw-2">*const </span>u8, |
| len: usize, |
| ) -> Bytes { |
| <span class="comment">// If the buffer is still tracked in a `Vec<u8>`. It is time to |
| // promote the vec to an `Arc`. This could potentially be called |
| // concurrently, so some care must be taken. |
| |
| // First, allocate a new `Shared` instance containing the |
| // `Vec` fields. It's important to note that `ptr`, `len`, |
| // and `cap` cannot be mutated without having `&mut self`. |
| // This means that these fields will not be concurrently |
| // updated and since the buffer hasn't been promoted to an |
| // `Arc`, those three fields still are the components of the |
| // vector. |
| </span><span class="kw">let </span>shared = Box::new(Shared { |
| buf, |
| cap: (offset <span class="kw">as </span>usize - buf <span class="kw">as </span>usize) + len, |
| <span class="comment">// Initialize refcount to 2. One for this reference, and one |
| // for the new clone that will be returned from |
| // `shallow_clone`. |
| </span>ref_cnt: AtomicUsize::new(<span class="number">2</span>), |
| }); |
| |
| <span class="kw">let </span>shared = Box::into_raw(shared); |
| |
| <span class="comment">// The pointer should be aligned, so this assert should |
| // always succeed. |
| </span><span class="macro">debug_assert!</span>( |
| <span class="number">0 </span>== (shared <span class="kw">as </span>usize & KIND_MASK), |
| <span class="string">"internal: Box<Shared> should have an aligned pointer"</span>, |
| ); |
| |
| <span class="comment">// Try compare & swapping the pointer into the `arc` field. |
| // `Release` is used synchronize with other threads that |
| // will load the `arc` field. |
| // |
| // If the `compare_exchange` fails, then the thread lost the |
| // race to promote the buffer to shared. The `Acquire` |
| // ordering will synchronize with the `compare_exchange` |
| // that happened in the other thread and the `Shared` |
| // pointed to by `actual` will be visible. |
| </span><span class="kw">match </span>atom.compare_exchange(ptr <span class="kw">as _</span>, shared <span class="kw">as _</span>, Ordering::AcqRel, Ordering::Acquire) { |
| <span class="prelude-val">Ok</span>(actual) => { |
| <span class="macro">debug_assert!</span>(actual <span class="kw">as </span>usize == ptr <span class="kw">as </span>usize); |
| <span class="comment">// The upgrade was successful, the new handle can be |
| // returned. |
| </span>Bytes { |
| ptr: offset, |
| len, |
| data: AtomicPtr::new(shared <span class="kw">as _</span>), |
| vtable: <span class="kw-2">&</span>SHARED_VTABLE, |
| } |
| } |
| <span class="prelude-val">Err</span>(actual) => { |
| <span class="comment">// The upgrade failed, a concurrent clone happened. Release |
| // the allocation that was made in this thread, it will not |
| // be needed. |
| </span><span class="kw">let </span>shared = Box::from_raw(shared); |
| mem::forget(<span class="kw-2">*</span>shared); |
| |
| <span class="comment">// Buffer already promoted to shared storage, so increment ref |
| // count. |
| </span>shallow_clone_arc(actual <span class="kw">as _</span>, offset, len) |
| } |
| } |
| } |
| |
| <span class="kw">unsafe fn </span>release_shared(ptr: <span class="kw-2">*mut </span>Shared) { |
| <span class="comment">// `Shared` storage... follow the drop steps from Arc. |
| </span><span class="kw">if </span>(<span class="kw-2">*</span>ptr).ref_cnt.fetch_sub(<span class="number">1</span>, Ordering::Release) != <span class="number">1 </span>{ |
| <span class="kw">return</span>; |
| } |
| |
| <span class="comment">// This fence is needed to prevent reordering of use of the data and |
| // deletion of the data. Because it is marked `Release`, the decreasing |
| // of the reference count synchronizes with this `Acquire` fence. This |
| // means that use of the data happens before decreasing the reference |
| // count, which happens before this fence, which happens before the |
| // deletion of the data. |
| // |
| // As explained in the [Boost documentation][1], |
| // |
| // > It is important to enforce any possible access to the object in one |
| // > thread (through an existing reference) to *happen before* deleting |
| // > the object in a different thread. This is achieved by a "release" |
| // > operation after dropping a reference (any access to the object |
| // > through this reference must obviously happened before), and an |
| // > "acquire" operation before deleting the object. |
| // |
| // [1]: (www.boost.org/doc/libs/1_55_0/doc/html/atomic/usage_examples.html) |
| // |
| // Thread sanitizer does not support atomic fences. Use an atomic load |
| // instead. |
| </span>(<span class="kw-2">*</span>ptr).ref_cnt.load(Ordering::Acquire); |
| |
| <span class="comment">// Drop the data |
| </span>drop(Box::from_raw(ptr)); |
| } |
| |
| <span class="comment">// Ideally we would always use this version of `ptr_map` since it is strict |
| // provenance compatible, but it results in worse codegen. We will however still |
| // use it on miri because it gives better diagnostics for people who test bytes |
| // code with miri. |
| // |
| // See https://github.com/tokio-rs/bytes/pull/545 for more info. |
| </span><span class="attribute">#[cfg(miri)] |
| </span><span class="kw">fn </span>ptr_map<F>(ptr: <span class="kw-2">*mut </span>u8, f: F) -> <span class="kw-2">*mut </span>u8 |
| <span class="kw">where |
| </span>F: FnOnce(usize) -> usize, |
| { |
| <span class="kw">let </span>old_addr = ptr <span class="kw">as </span>usize; |
| <span class="kw">let </span>new_addr = f(old_addr); |
| <span class="kw">let </span>diff = new_addr.wrapping_sub(old_addr); |
| ptr.wrapping_add(diff) |
| } |
| |
| <span class="attribute">#[cfg(not(miri))] |
| </span><span class="kw">fn </span>ptr_map<F>(ptr: <span class="kw-2">*mut </span>u8, f: F) -> <span class="kw-2">*mut </span>u8 |
| <span class="kw">where |
| </span>F: FnOnce(usize) -> usize, |
| { |
| <span class="kw">let </span>old_addr = ptr <span class="kw">as </span>usize; |
| <span class="kw">let </span>new_addr = f(old_addr); |
| new_addr <span class="kw">as </span><span class="kw-2">*mut </span>u8 |
| } |
| |
| <span class="comment">// compile-fails |
| |
| </span><span class="doccomment">/// ```compile_fail |
| /// use bytes::Bytes; |
| /// #[deny(unused_must_use)] |
| /// { |
| /// let mut b1 = Bytes::from("hello world"); |
| /// b1.split_to(6); |
| /// } |
| /// ``` |
| </span><span class="kw">fn </span>_split_to_must_use() {} |
| |
| <span class="doccomment">/// ```compile_fail |
| /// use bytes::Bytes; |
| /// #[deny(unused_must_use)] |
| /// { |
| /// let mut b1 = Bytes::from("hello world"); |
| /// b1.split_off(6); |
| /// } |
| /// ``` |
| </span><span class="kw">fn </span>_split_off_must_use() {} |
| |
| <span class="comment">// fuzz tests |
| </span><span class="attribute">#[cfg(all(test, loom))] |
| </span><span class="kw">mod </span>fuzz { |
| <span class="kw">use </span>loom::sync::Arc; |
| <span class="kw">use </span>loom::thread; |
| |
| <span class="kw">use </span><span class="kw">super</span>::Bytes; |
| <span class="attribute">#[test] |
| </span><span class="kw">fn </span>bytes_cloning_vec() { |
| loom::model(|| { |
| <span class="kw">let </span>a = Bytes::from(<span class="string">b"abcdefgh"</span>.to_vec()); |
| <span class="kw">let </span>addr = a.as_ptr() <span class="kw">as </span>usize; |
| |
| <span class="comment">// test the Bytes::clone is Sync by putting it in an Arc |
| </span><span class="kw">let </span>a1 = Arc::new(a); |
| <span class="kw">let </span>a2 = a1.clone(); |
| |
| <span class="kw">let </span>t1 = thread::spawn(<span class="kw">move </span>|| { |
| <span class="kw">let </span>b: Bytes = (<span class="kw-2">*</span>a1).clone(); |
| <span class="macro">assert_eq!</span>(b.as_ptr() <span class="kw">as </span>usize, addr); |
| }); |
| |
| <span class="kw">let </span>t2 = thread::spawn(<span class="kw">move </span>|| { |
| <span class="kw">let </span>b: Bytes = (<span class="kw-2">*</span>a2).clone(); |
| <span class="macro">assert_eq!</span>(b.as_ptr() <span class="kw">as </span>usize, addr); |
| }); |
| |
| t1.join().unwrap(); |
| t2.join().unwrap(); |
| }); |
| } |
| } |
| </code></pre></div> |
| </section></div></main><div id="rustdoc-vars" data-root-path="../../" data-current-crate="bytes" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0-nightly (5c8bff74b 2022-10-21)" ></div></body></html> |
