<!DOCTYPE html><htmllang="en"><head><metacharset="utf-8"><metaname="viewport"content="width=device-width, initial-scale=1.0"><metaname="generator"content="rustdoc"><metaname="description"content="Wrap a static data structure inside it so that we are able to access it without any `unsafe`."><metaname="keywords"content="rust, rustlang, rust-lang, UPSafeCell"><title>UPSafeCell in os::sync::up - Rust</title><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../../../SourceSerif4-Regular.ttf.woff2"><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../../../FiraSans-Regular.woff2"><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../../../FiraSans-Medium.woff2"><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../../../SourceCodePro-Regular.ttf.woff2"><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../../../SourceSerif4-Bold.ttf.woff2"><linkrel="preload"as="font"type="font/woff2"crossoriginhref="../../../SourceCodePro-Semibold.ttf.woff2"><linkrel="stylesheet"type="text/css"href="../../../normalize.css"><linkrel="stylesheet"type="text/css"href="../../../rustdoc.css"id="mainThemeStyle"><linkrel="stylesheet"type="text/css"href="../../../ayu.css"disabled><linkrel="stylesheet"type="text/css"href="../../../dark.css"disabled><linkrel="stylesheet"type="text/css"href="../../../light.css"id="themeStyle"><scriptid="default-settings"></script><scriptsrc="../../../storage.js"></script><scriptdefersrc="sidebar-items.js"></script><scriptdefersrc="../../../main.js"></script><noscript><linkrel="stylesheet"href="../../../noscript.css"></noscript><linkrel="alternate icon"type="image/png"href="../../../favicon-16x16.png"><linkrel="alternate icon"type="image/png"href="../../../favicon-32x32.png"><linkrel="icon"type="image/svg+xml"href="../../../favicon.svg"></head><bodyclass="rustdoc struct"><!--[if lte IE 11]><div class="warning">This old browser is unsupported and will most likely display funky things.</div><![endif]--><navclass="mobile-topbar"><buttonclass="sidebar-menu-toggle">☰</button><aclass="sidebar-logo"href="../../../os/index.html"><divclass="logo-container"><imgclass="rust-logo"src="../../../rust-logo.svg"alt="logo"></div>
</a><h2class="location"><ahref="#">UPSafeCell</a></h2><divclass="sidebar-elems"><section><divclass="block"><h3class="sidebar-title"><ahref="#fields">Fields</a></h3><ul><li><ahref="#structfield.inner">inner</a></li></ul></div><divclass="block"><h3class="sidebar-title"><ahref="#implementations">Methods</a></h3><ul><li><ahref="#method.exclusive_access">exclusive_access</a></li><li><ahref="#method.new">new</a></li></ul></div><divclass="block"><h3class="sidebar-title"><ahref="#trait-implementations">Trait Implementations</a></h3><ul><li><ahref="#impl-Sync-for-UPSafeCell%3CT%3E">Sync</a></li></ul></div><divclass="block"><h3class="sidebar-title"><ahref="#synthetic-implementations">Auto Trait Implementations</a></h3><ul><li><ahref="#impl-RefUnwindSafe-for-UPSafeCell%3CT%3E">!RefUnwindSafe</a></li><li><ahref="#impl-Send-for-UPSafeCell%3CT%3E">Send</a></li><li><ahref="#impl-Unpin-for-UPSafeCell%3CT%3E">Unpin</a></li><li><ahref="#impl-UnwindSafe-for-UPSafeCell%3CT%3E">UnwindSafe</a></li></ul></div><divclass="block"><h3class="sidebar-title"><ahref="#blanket-implementations">Blanket Implementations</a></h3><ul><li><ahref="#impl-Any-for-UPSafeCell%3CT%3E">Any</a></li><li><ahref="#impl-Borrow%3CT%3E-for-UPSafeCell%3CT%3E">Borrow<T></a></li><li><ahref="#impl-BorrowMut%3CT%3E-for-UPSafeCell%3CT%3E">BorrowMut<T></a></li><li><ahref="#impl-From%3CT%3E-for-UPSafeCell%3CT%3E">From<T></a></li><li><ahref="#impl-Into%3CU%3E-for-UPSafeCell%3CT%3E">Into<U></a></li><li><ahref="#impl-TryFrom%3CU%3E-for-UPSafeCell%3CT%3E">TryFrom<U></a></li><li><ahref="#impl-TryInto%3CU%3E-for-UPSafeCell%3CT%3E">TryInto<U></a></li></ul></div></section><h2class="location"><ahref="index.html">In os::sync::up</a></h2></div></nav><main><divclass="width-limiter"><divclass="sub-container"><aclass="sub-logo-container"href="../../../os/index.html"><imgclass="rust-logo"src="../../../rust-logo.svg"alt="logo"></a><navclass="sub"><formclass="search-form"><divclass="search-container"><span></span><inputclass="search-input"name="search"autocomplete="off"spellcheck="false"placeholder="Click or press ‘S’ to search, ‘?’ for more options…"type="search"><divid="help-button"title="help"tabindex="-1"><buttontype="button">?</button></div><divid="settings-menu"tabindex="-1">
}</code></pre></div><detailsclass="rustdoc-toggle top-doc"open><summaryclass="hideme"><span>Expand description</span></summary><divclass="docblock"><p>Wrap a static data structure inside it so that we are
able to access it without any <code>unsafe</code>.</p>
<p>We should only use it in uniprocessor.</p>
<p>In order to get mutable reference of inner data, call
</div><h2id="implementations"class="small-section-header">Implementations<ahref="#implementations"class="anchor"></a></h2><divid="implementations-list"><detailsclass="rustdoc-toggle implementors-toggle"open><summary><sectionid="impl-UPSafeCell%3CT%3E"class="impl has-srclink"><spanclass="rightside"><aclass="srclink"href="../../../src/os/sync/up.rs.html#18-30">source</a></span><ahref="#impl-UPSafeCell%3CT%3E"class="anchor"></a><h3class="code-header in-band">impl<T><aclass="struct"href="struct.UPSafeCell.html"title="struct os::sync::up::UPSafeCell">UPSafeCell</a><T></h3></section></summary><divclass="impl-items"><detailsclass="rustdoc-toggle method-toggle"open><summary><sectionid="method.new"class="method has-srclink"><spanclass="rightside"><aclass="srclink"href="../../../src/os/sync/up.rs.html#21-25">source</a></span><h4class="code-header">pub unsafe fn <ahref="#method.new"class="fnname">new</a>(value: T) -> Self</h4></section></summary><divclass="docblock"><p>User is responsible to guarantee that inner struct is only used in
</div></details><detailsclass="rustdoc-toggle method-toggle"open><summary><sectionid="method.exclusive_access"class="method has-srclink"><spanclass="rightside"><aclass="srclink"href="../../../src/os/sync/up.rs.html#27-29">source</a></span><h4class="code-header">pub fn <ahref="#method.exclusive_access"class="fnname">exclusive_access</a>(&self) -><aclass="struct"href="https://doc.rust-lang.org/nightly/core/cell/struct.RefMut.html"title="struct core::cell::RefMut">RefMut</a><'_, T></h4></section></summary><divclass="docblock"><p>Exclusive access inner data in UPSafeCell. Panic if the data has been borrowed.</p>
</div></details></div></details></div><h2id="trait-implementations"class="small-section-header">Trait Implementations<ahref="#trait-implementations"class="anchor"></a></h2><divid="trait-implementations-list"><sectionid="impl-Sync-for-UPSafeCell%3CT%3E"class="impl has-srclink"><spanclass="rightside"><aclass="srclink"href="../../../src/os/sync/up.rs.html#16">source</a></span><ahref="#impl-Sync-for-UPSafeCell%3CT%3E"class="anchor"></a><h3class="code-header in-band">impl<T><aclass="trait"href="https://doc.rust-lang.org/nightly/core/marker/trait.Sync.html"title="trait core::marker::Sync">Sync</a> for <aclass="struct"href="struct.UPSafeCell.html"title="struct os::sync::up::UPSafeCell">UPSafeCell</a><T></h3></section></div><h2id="synthetic-implementations"class="small-section-header">Auto Trait Implementations<ahref="#synthetic-implementations"class="anchor"></a></h2><divid="synthetic-implementations-list"><sectionid="impl-RefUnwindSafe-for-UPSafeCell%3CT%3E"class="impl has-srclink"><ahref="#impl-RefUnwindSafe-for-UPSafeCell%3CT%3E"class="anchor"></a><h3class="code-header in-band">impl<T> !<aclass="trait"href="https://doc.rust-lang.org/nightly/core/panic/unwind_safe/trait.RefUnwindSafe.html"title="trait core::panic::unwind_safe::RefUnwindSafe">RefUnwindSafe</a> for <aclass="struct"href="struct.UPSafeCell.html"title="struct os::sync::up::UPSafeCell">UPSafeCell</a><T></h3></section><sectionid="impl-Send-for-UPSafeCell%3CT%3E"class="impl has-srclink"><ahref="#impl-Send-for-UPSafeCell%3CT%3E"class="anchor"></a><h3class="code-header in-band">impl<T><aclass="trait"href="https://doc.rust-lang.org/nightly/core/marker/trait.Send.html"title="trait core::marker::Send">Send</a> for <aclass="struct"href="struct.UPSafeCell.html"title="struct os::sync::up::UPSafeCell">UPSafeCell</a><T><spanclass="where fmt-newline">where<br> T: <aclass="trait"href="https://doc.rust-lang.org/nightly/core/marker/trait.Send.html"title="trait core::marker::Send">Send</a>, </span></h3></section><sectionid="impl-Unpin-for-UPSafeCell%3CT%3E"class="impl has-srclink"><ahref="#impl-Unpin-for-UPSafeCell%3CT%3E"class="anchor"></a><h3class="code-header in-band">impl<T><aclass="trait"href="https://doc.rust-lang.org/nightly/core/marker/trait.Unpin.html"title="trait core::marker::Unpin">Unpin</a> for <aclass="struct"href="struct.UPSafeCell.html"title="struct os::sync::up::UPSafeCell">UPSafeCell</a><T><spanclass="where fmt-newline">where<br> T: <aclass="trait"href="https://doc.rust-lang.org/nightly/core/marker/trait.Unpin.html"title="trait core::marker::Unpin">Unpin</a>, </span></h3></section><sectionid="impl-UnwindSafe-for-UPSafeCell%3CT%3E"class="impl has-srclink"><ahref="#impl-UnwindSafe-for-UPSafeCell%3CT%3E"class="anchor"></a><h3class="code-header in-band">impl<T><aclass="trait"href="https://doc.rust-lang.org/nightly/core/panic/unwind_safe/trait.UnwindSafe.html"title="trait core::panic::unwind_safe::UnwindSafe">UnwindSafe</a> for <aclass="struct"href="struct.UPSafeCell.html"title="struct os::sync::up::UPSafeCell">UPSafeCell</a><T><spanclass="where fmt-newline">where<br> T: <aclass="trait"href="https://doc.rust-lang.org/nightly/core/panic/unwind_safe/trait.UnwindSafe.html"title="trait core::panic::unwind_safe::UnwindSafe">UnwindSafe</a>, </span></h3></section></div><h2id="blanket-implementations"class="small-section-header">Blanket Implementations<ahref="#blanket-implementations"class="anchor"></a></h2><divid="blanket-implementations-list"><detailsclass="rustdoc-toggle implementors-toggle"><summary><sectionid="impl-Any-for-UPSafeCell%3CT%3E"class="impl has-srclink"><spanclass="rightside"><aclass="srclink"href="https://doc.rust-lang.org/nightly/src/core/any.rs.html#203">source</a></span><ahref="#impl-Any-for-UPSafeCell%3CT%3E"class="anchor"></a><h3class="code-header in-band">impl<T><aclass="trait"href="https://doc.rust-lan
</div></details></div></details><detailsclass="rustdoc-toggle implementors-toggle"><summary><sectionid="impl-Borrow%3CT%3E-for-UPSafeCell%3CT%3E"class="impl has-srclink"><spanclass="rightside"><aclass="srclink"href="https://doc.rust-lang.org/nightly/src/core/borrow.rs.html#209">source</a></span><ahref="#impl-Borrow%3CT%3E-for-UPSafeCell%3CT%3E"class="anchor"></a><h3class="code-header in-band">impl<T><aclass="trait"href="https://doc.rust-lang.org/nightly/core/borrow/trait.Borrow.html"title="trait core::borrow::Borrow">Borrow</a><T> for T <spanclass="where fmt-newline">where<br> T: ?<aclass="trait"href="https://doc.rust-lang.org/nightly/core/marker/trait.Sized.html"title="trait core::marker::Sized">Sized</a>, </span></h3></section></summary><divclass="impl-items"><detailsclass="rustdoc-toggle method-toggle"open><summary><sectionid="method.borrow"class="method trait-impl has-srclink"><spanclass="rightside"><spanclass="since"title="const unstable">const: <ahref="https://github.com/rust-lang/rust/issues/91522"title="Tracking issue for const_borrow">unstable</a></span> · <aclass="srclink"href="https://doc.rust-lang.org/nightly/src/core/borrow.rs.html#211">source</a></span><ahref="#method.borrow"class="anchor"></a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/nightly/core/borrow/trait.Borrow.html#tymethod.borrow"class="fnname">borrow</a>(&self) -><aclass="primitive"href="https://doc.rust-lang.org/nightly/core/primitive.reference.html">&</a>T</h4></section></summary><divclass='docblock'><p>Immutably borrows from an owned value. <ahref="https://doc.rust-lang.org/nightly/core/borrow/trait.Borrow.html#tymethod.borrow">Read more</a></p>
</div></details></div></details><detailsclass="rustdoc-toggle implementors-toggle"><summary><sectionid="impl-BorrowMut%3CT%3E-for-UPSafeCell%3CT%3E"class="impl has-srclink"><spanclass="rightside"><aclass="srclink"href="https://doc.rust-lang.org/nightly/src/core/borrow.rs.html#218">source</a></span><ahref="#impl-BorrowMut%3CT%3E-for-UPSafeCell%3CT%3E"class="anchor"></a><h3class="code-header in-band">impl<T><aclass="trait"href="https://doc.rust-lang.org/nightly/core/borrow/trait.BorrowMut.html"title="trait core::borrow::BorrowMut">BorrowMut</a><T> for T <spanclass="where fmt-newline">where<br> T: ?<aclass="trait"href="https://doc.rust-lang.org/nightly/core/marker/trait.Sized.html"title="trait core::marker::Sized">Sized</a>, </span></h3></section></summary><divclass="impl-items"><detailsclass="rustdoc-toggle method-toggle"open><summary><sectionid="method.borrow_mut"class="method trait-impl has-srclink"><spanclass="rightside"><spanclass="since"title="const unstable">const: <ahref="https://github.com/rust-lang/rust/issues/91522"title="Tracking issue for const_borrow">unstable</a></span> · <aclass="srclink"href="https://doc.rust-lang.org/nightly/src/core/borrow.rs.html#219">source</a></span><ahref="#method.borrow_mut"class="anchor"></a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/nightly/core/borrow/trait.BorrowMut.html#tymethod.borrow_mut"class="fnname">borrow_mut</a>(&mut self) -><aclass="primitive"href="https://doc.rust-lang.org/nightly/core/primitive.reference.html">&mut </a>T</h4></section></summary><divclass='docblock'><p>Mutably borrows from an owned value. <ahref="https://doc.rust-lang.org/nightly/core/borrow/trait.BorrowMut.html#tymethod.borrow_mut">Read more</a></p>
</div></details></div></details><detailsclass="rustdoc-toggle implementors-toggle"><summary><sectionid="impl-From%3CT%3E-for-UPSafeCell%3CT%3E"class="impl has-srclink"><spanclass="rightside"><aclass="srclink"href="https://doc.rust-lang.org/nightly/src/core/convert/mod.rs.html#557">source</a></span><ahref="#impl-From%3CT%3E-for-UPSafeCell%3CT%3E"class="anchor"></a><h3class="code-header in-band">impl<T><aclass="trait"href="https://doc.rust-lang.org/nightly/core/convert/trait.From.html"title="trait core::convert::From">From</a><T> for T</h3></section></summary><divclass="impl-items"><detailsclass="rustdoc-toggle method-toggle"open><summary><sectionid="method.from"class="method trait-impl has-srclink"><spanclass="rightside"><spanclass="since"title="const unstable">const: <ahref="https://github.com/rust-lang/rust/issues/88674"title="Tracking issue for const_convert">unstable</a></span> · <aclass="srclink"href="https://doc.rust-lang.org/nightly/src/core/convert/mod.rs.html#559">source</a></span><ahref="#method.from"class="anchor"></a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/nightly/core/convert/trait.From.html#tymethod.from"class="fnname">from</a>(t: T) -> T</h4></section></summary><divclass="docblock"><p>Returns the argument unchanged.</p>
</div></details></div></details><detailsclass="rustdoc-toggle implementors-toggle"><summary><sectionid="impl-Into%3CU%3E-for-UPSafeCell%3CT%3E"class="impl has-srclink"><spanclass="rightside"><aclass="srclink"href="https://doc.rust-lang.org/nightly/src/core/convert/mod.rs.html#541">source</a></span><ahref="#impl-Into%3CU%3E-for-UPSafeCell%3CT%3E"class="anchor"></a><h3class="code-header in-band">impl<T, U><aclass="trait"href="https://doc.rust-lang.org/nightly/core/convert/trait.Into.html"title="trait core::convert::Into">Into</a><U> for T <spanclass="where fmt-newline">where<br> U: <aclass="trait"href="https://doc.rust-lang.org/nightly/core/convert/trait.From.html"title="trait core::convert::From">From</a><T>, </span></h3></section></summary><divclass="impl-items"><detailsclass="rustdoc-toggle method-toggle"open><summary><sectionid="method.into"class="method trait-impl has-srclink"><spanclass="rightside"><spanclass="since"title="const unstable">const: <ahref="https://github.com/rust-lang/rust/issues/88674"title="Tracking issue for const_convert">unstable</a></span> · <aclass="srclink"href="https://doc.rust-lang.org/nightly/src/core/convert/mod.rs.html#549">source</a></span><ahref="#method.into"class="anchor"></a><h4class="code-header">fn <ahref="https://doc.rust-lang.org/nightly/core/convert/trait.Into.html#tymethod.into"class="fnname">into</a>(self) -> U</h4></section></summary><divclass="docblock"><p>Calls <code>U::from(self)</code>.</p>
</div></details></div></details><detailsclass="rustdoc-toggle implementors-toggle"><summary><sectionid="impl-TryFrom%3CU%3E-for-UPSafeCell%3CT%3E"class="impl has-srclink"><spanclass="rightside"><aclass="srclink"href="https://doc.rust-lang.org/nightly/src/core/convert/mod.rs.html#598">source</a></span><ahref="#impl-TryFrom%3CU%3E-for-UPSafeCell%3CT%3E"class="anchor"></a><h3class="code-header in-band">impl<T, U><aclass="trait"href="https://doc.rust-lang.org/nightly/core/convert/trait.TryFrom.html"title="trait core::convert::TryFrom">TryFrom</a><U> for T <spanclass="where fmt-newline">where<br> U: <aclass="trait"href="https://doc.rust-lang.org/nightly/core/convert/trait.Into.html"title="trait core::convert::Into">Into</a><T>, </span></h3></section></summary><divclass="impl-items"><detailsclass="rustdoc-toggle"open><summary><sectionid="associatedtype.Error-1"class="associatedtype trait-impl has-srclink"><ahref="#associatedtype.Error-1"class="anchor"></a><h4class="code-header">type <ahref="https://doc.rust-lang.org/nightly/core/convert/trait.TryFrom.html#associatedtype.Error"class="associatedtype">Error</a> = <aclass="enum"href="https://doc.rust-lang.org/nightly/core/convert/enum.Infallible.html"title="enum core::convert::Infallible">Infallible</a></h4></section></summary><divclass='docblock'><p>The type returned in the event of a conversion error.</p>
</div></details></div></details><detailsclass="rustdoc-toggle implementors-toggle"><summary><sectionid="impl-TryInto%3CU%3E-for-UPSafeCell%3CT%3E"class="impl has-srclink"><spanclass="rightside"><aclass="srclink"href="https://doc.rust-lang.org/nightly/src/core/convert/mod.rs.html#583">source</a></span><ahref="#impl-TryInto%3CU%3E-for-UPSafeCell%3CT%3E"class="anchor"></a><h3class="code-header in-band">impl<T, U><aclass="trait"href="https://doc.rust-lang.org/nightly/core/convert/trait.TryInto.html"title="trait core::convert::TryInto">TryInto</a><U> for T <spanclass="where fmt-newline">where<br> U: <aclass="trait"href="https://doc.rust-lang.org/nightly/core/convert/trait.TryFrom.html"title="trait core::convert::TryFrom">TryFrom</a><T>, </span></h3></section></summary><divclass="impl-items"><detailsclass="rustdoc-toggle"open><summary><sectionid="associatedtype.Error"class="associatedtype trait-impl has-srclink"><ahref="#associatedtype.Error"class="anchor"></a><h4class="code-header">type <ahref="https://doc.rust-lang.org/nightly/core/convert/trait.TryInto.html#associatedtype.Error"class="associatedtype">Error</a> = <U as <aclass="trait"href="https://doc.rust-lang.org/nightly/core/convert/trait.TryFrom.html"title="trait core::convert::TryFrom">TryFrom</a><T>>::<aclass="associatedtype"href="https://doc.rust-lang.org/nightly/core/convert/trait.TryFrom.html#associatedtype.Error"title="type core::convert::TryFrom::Error">Error</a></h4></section></summary><divclass='docblock'><p>The type returned in the event of a conversion error.</p>
