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<p class='location'>Struct QrwLock</p><div class="sidebar-elems"><div class="block items"><a class="sidebar-title" href="#methods">Methods</a><div class="sidebar-links"><a href="#method.new">new</a><a href="#method.read">read</a><a href="#method.write">write</a><a href="#method.enqueue_lock_request">enqueue_lock_request</a><a href="#method.get_mut">get_mut</a><a href="#method.as_ptr">as_ptr</a><a href="#method.as_mut_ptr">as_mut_ptr</a><a href="#method.process_queues">process_queues</a><a href="#method.upgrade_read_lock">upgrade_read_lock</a><a href="#method.downgrade_write_lock">downgrade_write_lock</a><a href="#method.release_read_lock">release_read_lock</a><a href="#method.release_write_lock">release_write_lock</a></div><a class="sidebar-title" href="#implementations">Trait Implementations</a><div class="sidebar-links"><a href="#impl-Debug">Debug</a><a href="#impl-From%3CT%3E">From<T></a><a href="#impl-Clone">Clone</a></div></div><p class='location'><a href='index.html'>qutex</a></p><script>window.sidebarCurrent = {name: 'QrwLock', ty: 'struct', relpath: ''};</script><script defer src="sidebar-items.js"></script></div>
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<h1 class='fqn'><span class='in-band'>Struct <a href='index.html'>qutex</a>::<wbr><a class="struct" href=''>QrwLock</a></span><span class='out-of-band'><span id='render-detail'>
<a id="toggle-all-docs" href="javascript:void(0)" title="collapse all docs">
[<span class='inner'>−</span>]
</a>
</span><a class='srclink' href='../src/qutex/qrw_lock.rs.html#461-463' title='goto source code'>[src]</a></span></h1>
<pre class='rust struct'>pub struct QrwLock<T> { /* fields omitted */ }</pre><div class='docblock'><p>A queue-backed read/write data lock.</p>
<p>As with any queue-backed system, deadlocks must be carefully avoided when
interoperating with other queues.</p>
</div>
<h2 id='methods' class='small-section-header'>
Methods<a href='#methods' class='anchor'></a>
</h2>
<h3 id='impl' class='impl'><span class='in-band'><code>impl<T> <a class="struct" href="../qutex/struct.QrwLock.html" title="struct qutex::QrwLock">QrwLock</a><T></code><a href='#impl' class='anchor'></a></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/qutex/qrw_lock.rs.html#465-872' title='goto source code'>[src]</a></span></h3>
<div class='impl-items'><h4 id='method.new' class="method"><span id='new.v' class='invisible'><code>pub fn <a href='#method.new' class='fnname'>new</a>(val: T) -> <a class="struct" href="../qutex/struct.QrwLock.html" title="struct qutex::QrwLock">QrwLock</a><T></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/qutex/qrw_lock.rs.html#468-472' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Creates and returns a new <code>QrwLock</code>.</p>
</div><h4 id='method.read' class="method"><span id='read.v' class='invisible'><code>pub fn <a href='#method.read' class='fnname'>read</a>(self) -> <a class="struct" href="../qutex/struct.FutureReadGuard.html" title="struct qutex::FutureReadGuard">FutureReadGuard</a><T></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/qutex/qrw_lock.rs.html#477-483' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Returns a new <code>FutureReadGuard</code> which can be used as a future and will
resolve into a <code>ReadGuard</code>.</p>
</div><h4 id='method.write' class="method"><span id='write.v' class='invisible'><code>pub fn <a href='#method.write' class='fnname'>write</a>(self) -> <a class="struct" href="../qutex/struct.FutureWriteGuard.html" title="struct qutex::FutureWriteGuard">FutureWriteGuard</a><T></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/qutex/qrw_lock.rs.html#488-494' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Returns a new <code>FutureWriteGuard</code> which can be used as a future and will
resolve into a <code>WriteGuard</code>.</p>
</div><h4 id='method.enqueue_lock_request' class="method"><span id='enqueue_lock_request.v' class='invisible'><code>pub unsafe fn <a href='#method.enqueue_lock_request' class='fnname'>enqueue_lock_request</a>(&self, req: <a class="struct" href="../qutex/struct.QrwRequest.html" title="struct qutex::QrwRequest">QrwRequest</a>)</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/qutex/qrw_lock.rs.html#503-505' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Pushes a lock request onto the queue.</p>
</div><h4 id='method.get_mut' class="method"><span id='get_mut.v' class='invisible'><code>pub fn <a href='#method.get_mut' class='fnname'>get_mut</a>(&mut self) -> <a class="enum" href="https://doc.rust-lang.org/nightly/core/option/enum.Option.html" title="enum core::option::Option">Option</a><<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.reference.html">&mut </a>T></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/qutex/qrw_lock.rs.html#514-516' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Returns a mutable reference to the inner <code>Vec</code> if there are currently
no other copies of this <code>QrwLock</code>.</p>
<p>Since this call borrows the inner lock mutably, no actual locking needs to
take place---the mutable borrow statically guarantees no locks exist.</p>
</div><h4 id='method.as_ptr' class="method"><span id='as_ptr.v' class='invisible'><code>pub fn <a href='#method.as_ptr' class='fnname'>as_ptr</a>(&self) -> <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.pointer.html">*const T</a></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/qutex/qrw_lock.rs.html#521-523' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Returns a reference to the inner value.</p>
</div><h4 id='method.as_mut_ptr' class="method"><span id='as_mut_ptr.v' class='invisible'><code>pub fn <a href='#method.as_mut_ptr' class='fnname'>as_mut_ptr</a>(&self) -> <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.pointer.html">*mut T</a></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/qutex/qrw_lock.rs.html#528-530' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Returns a mutable reference to the inner value.</p>
</div><h4 id='method.process_queues' class="method"><span id='process_queues.v' class='invisible'><code>pub unsafe fn <a href='#method.process_queues' class='fnname'>process_queues</a>(&self)</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/qutex/qrw_lock.rs.html#699-744' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Pops the next lock request in the queue if possible.</p>
</div><h4 id='method.upgrade_read_lock' class="method"><span id='upgrade_read_lock.v' class='invisible'><code>pub unsafe fn <a href='#method.upgrade_read_lock' class='fnname'>upgrade_read_lock</a>(&self) -> <a class="enum" href="https://doc.rust-lang.org/nightly/core/result/enum.Result.html" title="enum core::result::Result">Result</a><<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.unit.html">()</a>, <a class="struct" href="../futures/sync/oneshot/struct.Receiver.html" title="struct futures::sync::oneshot::Receiver">Receiver</a><<a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.unit.html">()</a>>></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/qutex/qrw_lock.rs.html#767-790' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Converts a single read lock (read count of '1') into a write lock.</p>
<p>Returns an error containing a oneshot receiver if there is currently
more than one read lock. When the read count reaches one, the receiver
channel will be completed (i.e. poll it).</p>
<p>Panics if there are no read locks.</p>
<p>Do not call this method directly unless you are using a custom guard
or are otherwise managing the lock state manually. Use
<code>ReadGuard::upgrade</code> instead.</p>
</div><h4 id='method.downgrade_write_lock' class="method"><span id='downgrade_write_lock.v' class='invisible'><code>pub unsafe fn <a href='#method.downgrade_write_lock' class='fnname'>downgrade_write_lock</a>(&self)</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/qutex/qrw_lock.rs.html#797-812' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Converts a write lock into a read lock then processes the queue,
allowing additional read requests to acquire locks.</p>
<p>Use <code>WriteGuard::downgrade</code> rather than calling this directly.</p>
</div><h4 id='method.release_read_lock' class="method"><span id='release_read_lock.v' class='invisible'><code>pub unsafe fn <a href='#method.release_read_lock' class='fnname'>release_read_lock</a>(&self)</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/qutex/qrw_lock.rs.html#823-841' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Decreases the reader count by one and unparks the next requester task
in the queue if possible.</p>
<p>If a reader is waiting to be upgraded and the read lock count reaches
1, the upgrade sender will be completed.</p>
</div><h4 id='method.release_write_lock' class="method"><span id='release_write_lock.v' class='invisible'><code>pub unsafe fn <a href='#method.release_write_lock' class='fnname'>release_write_lock</a>(&self)</code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/qutex/qrw_lock.rs.html#848-871' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Unlocks this (the caller's) lock and unparks the next requester task
in the queue if possible.</p>
</div></div>
<h2 id='implementations' class='small-section-header'>
Trait Implementations<a href='#implementations' class='anchor'></a>
</h2>
<h3 id='impl-Debug' class='impl'><span class='in-band'><code>impl<T: <a class="trait" href="https://doc.rust-lang.org/nightly/core/fmt/trait.Debug.html" title="trait core::fmt::Debug">Debug</a>> <a class="trait" href="https://doc.rust-lang.org/nightly/core/fmt/trait.Debug.html" title="trait core::fmt::Debug">Debug</a> for <a class="struct" href="../qutex/struct.QrwLock.html" title="struct qutex::QrwLock">QrwLock</a><T></code><a href='#impl-Debug' class='anchor'></a></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/qutex/qrw_lock.rs.html#460' title='goto source code'>[src]</a></span></h3>
<div class='impl-items'><h4 id='method.fmt' class="method"><span id='fmt.v' class='invisible'><code>fn <a href='https://doc.rust-lang.org/nightly/core/fmt/trait.Debug.html#tymethod.fmt' class='fnname'>fmt</a>(&self, __arg_0: &mut <a class="struct" href="https://doc.rust-lang.org/nightly/core/fmt/struct.Formatter.html" title="struct core::fmt::Formatter">Formatter</a>) -> <a class="type" href="https://doc.rust-lang.org/nightly/core/fmt/type.Result.html" title="type core::fmt::Result">Result</a></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/qutex/qrw_lock.rs.html#460' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Formats the value using the given formatter. <a href="https://doc.rust-lang.org/nightly/core/fmt/trait.Debug.html#tymethod.fmt">Read more</a></p>
</div></div><h3 id='impl-From%3CT%3E' class='impl'><span class='in-band'><code>impl<T> <a class="trait" href="https://doc.rust-lang.org/nightly/core/convert/trait.From.html" title="trait core::convert::From">From</a><T> for <a class="struct" href="../qutex/struct.QrwLock.html" title="struct qutex::QrwLock">QrwLock</a><T></code><a href='#impl-From%3CT%3E' class='anchor'></a></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/qutex/qrw_lock.rs.html#874-879' title='goto source code'>[src]</a></span></h3>
<div class='impl-items'><h4 id='method.from' class="method"><span id='from.v' class='invisible'><code>fn <a href='https://doc.rust-lang.org/nightly/core/convert/trait.From.html#tymethod.from' class='fnname'>from</a>(val: T) -> <a class="struct" href="../qutex/struct.QrwLock.html" title="struct qutex::QrwLock">QrwLock</a><T></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/qutex/qrw_lock.rs.html#876-878' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Performs the conversion.</p>
</div></div><h3 id='impl-Clone' class='impl'><span class='in-band'><code>impl<T> <a class="trait" href="https://doc.rust-lang.org/nightly/core/clone/trait.Clone.html" title="trait core::clone::Clone">Clone</a> for <a class="struct" href="../qutex/struct.QrwLock.html" title="struct qutex::QrwLock">QrwLock</a><T></code><a href='#impl-Clone' class='anchor'></a></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/qutex/qrw_lock.rs.html#882-889' title='goto source code'>[src]</a></span></h3>
<div class='impl-items'><h4 id='method.clone' class="method"><span id='clone.v' class='invisible'><code>fn <a href='https://doc.rust-lang.org/nightly/core/clone/trait.Clone.html#tymethod.clone' class='fnname'>clone</a>(&self) -> <a class="struct" href="../qutex/struct.QrwLock.html" title="struct qutex::QrwLock">QrwLock</a><T></code></span><span class='out-of-band'><div class='ghost'></div><a class='srclink' href='../src/qutex/qrw_lock.rs.html#884-888' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Returns a copy of the value. <a href="https://doc.rust-lang.org/nightly/core/clone/trait.Clone.html#tymethod.clone">Read more</a></p>
</div><h4 id='method.clone_from' class="method"><span id='clone_from.v' class='invisible'><code>fn <a href='https://doc.rust-lang.org/nightly/core/clone/trait.Clone.html#method.clone_from' class='fnname'>clone_from</a>(&mut self, source: <a class="primitive" href="https://doc.rust-lang.org/nightly/std/primitive.reference.html">&</a>Self)</code></span><span class='out-of-band'><div class='ghost'></div><div class='since' title='Stable since Rust version 1.0.0'>1.0.0</div><a class='srclink' href='https://doc.rust-lang.org/nightly/src/core/clone.rs.html#112-114' title='goto source code'>[src]</a></span></h4>
<div class='docblock'><p>Performs copy-assignment from <code>source</code>. <a href="https://doc.rust-lang.org/nightly/core/clone/trait.Clone.html#method.clone_from">Read more</a></p>
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