| <!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/h2-0.3.19/src/proto/streams/stream.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>stream.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="../../../../h2/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="../../../../h2/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="520">520</span> |
| <span id="521">521</span> |
| </pre><pre class="rust"><code><span class="kw">use super</span>::<span class="kw-2">*</span>; |
| |
| <span class="kw">use </span>std::task::{Context, Waker}; |
| <span class="kw">use </span>std::time::Instant; |
| <span class="kw">use </span>std::usize; |
| |
| <span class="doccomment">/// Tracks Stream related state |
| /// |
| /// # Reference counting |
| /// |
| /// There can be a number of outstanding handles to a single Stream. These are |
| /// tracked using reference counting. The `ref_count` field represents the |
| /// number of outstanding userspace handles that can reach this stream. |
| /// |
| /// It's important to note that when the stream is placed in an internal queue |
| /// (such as an accept queue), this is **not** tracked by a reference count. |
| /// Thus, `ref_count` can be zero and the stream still has to be kept around. |
| </span><span class="attribute">#[derive(Debug)] |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">struct </span>Stream { |
| <span class="doccomment">/// The h2 stream identifier |
| </span><span class="kw">pub </span>id: StreamId, |
| |
| <span class="doccomment">/// Current state of the stream |
| </span><span class="kw">pub </span>state: State, |
| |
| <span class="doccomment">/// Set to `true` when the stream is counted against the connection's max |
| /// concurrent streams. |
| </span><span class="kw">pub </span>is_counted: bool, |
| |
| <span class="doccomment">/// Number of outstanding handles pointing to this stream |
| </span><span class="kw">pub </span>ref_count: usize, |
| |
| <span class="comment">// ===== Fields related to sending ===== |
| </span><span class="doccomment">/// Next node in the accept linked list |
| </span><span class="kw">pub </span>next_pending_send: <span class="prelude-ty">Option</span><store::Key>, |
| |
| <span class="doccomment">/// Set to true when the stream is pending accept |
| </span><span class="kw">pub </span>is_pending_send: bool, |
| |
| <span class="doccomment">/// Send data flow control |
| </span><span class="kw">pub </span>send_flow: FlowControl, |
| |
| <span class="doccomment">/// Amount of send capacity that has been requested, but not yet allocated. |
| </span><span class="kw">pub </span>requested_send_capacity: WindowSize, |
| |
| <span class="doccomment">/// Amount of data buffered at the prioritization layer. |
| /// TODO: Technically this could be greater than the window size... |
| </span><span class="kw">pub </span>buffered_send_data: usize, |
| |
| <span class="doccomment">/// Task tracking additional send capacity (i.e. window updates). |
| </span>send_task: <span class="prelude-ty">Option</span><Waker>, |
| |
| <span class="doccomment">/// Frames pending for this stream being sent to the socket |
| </span><span class="kw">pub </span>pending_send: buffer::Deque, |
| |
| <span class="doccomment">/// Next node in the linked list of streams waiting for additional |
| /// connection level capacity. |
| </span><span class="kw">pub </span>next_pending_send_capacity: <span class="prelude-ty">Option</span><store::Key>, |
| |
| <span class="doccomment">/// True if the stream is waiting for outbound connection capacity |
| </span><span class="kw">pub </span>is_pending_send_capacity: bool, |
| |
| <span class="doccomment">/// Set to true when the send capacity has been incremented |
| </span><span class="kw">pub </span>send_capacity_inc: bool, |
| |
| <span class="doccomment">/// Next node in the open linked list |
| </span><span class="kw">pub </span>next_open: <span class="prelude-ty">Option</span><store::Key>, |
| |
| <span class="doccomment">/// Set to true when the stream is pending to be opened |
| </span><span class="kw">pub </span>is_pending_open: bool, |
| |
| <span class="doccomment">/// Set to true when a push is pending for this stream |
| </span><span class="kw">pub </span>is_pending_push: bool, |
| |
| <span class="comment">// ===== Fields related to receiving ===== |
| </span><span class="doccomment">/// Next node in the accept linked list |
| </span><span class="kw">pub </span>next_pending_accept: <span class="prelude-ty">Option</span><store::Key>, |
| |
| <span class="doccomment">/// Set to true when the stream is pending accept |
| </span><span class="kw">pub </span>is_pending_accept: bool, |
| |
| <span class="doccomment">/// Receive data flow control |
| </span><span class="kw">pub </span>recv_flow: FlowControl, |
| |
| <span class="kw">pub </span>in_flight_recv_data: WindowSize, |
| |
| <span class="doccomment">/// Next node in the linked list of streams waiting to send window updates. |
| </span><span class="kw">pub </span>next_window_update: <span class="prelude-ty">Option</span><store::Key>, |
| |
| <span class="doccomment">/// True if the stream is waiting to send a window update |
| </span><span class="kw">pub </span>is_pending_window_update: bool, |
| |
| <span class="doccomment">/// The time when this stream may have been locally reset. |
| </span><span class="kw">pub </span>reset_at: <span class="prelude-ty">Option</span><Instant>, |
| |
| <span class="doccomment">/// Next node in list of reset streams that should expire eventually |
| </span><span class="kw">pub </span>next_reset_expire: <span class="prelude-ty">Option</span><store::Key>, |
| |
| <span class="doccomment">/// Frames pending for this stream to read |
| </span><span class="kw">pub </span>pending_recv: buffer::Deque, |
| |
| <span class="doccomment">/// When the RecvStream drop occurs, no data should be received. |
| </span><span class="kw">pub </span>is_recv: bool, |
| |
| <span class="doccomment">/// Task tracking receiving frames |
| </span><span class="kw">pub </span>recv_task: <span class="prelude-ty">Option</span><Waker>, |
| |
| <span class="doccomment">/// The stream's pending push promises |
| </span><span class="kw">pub </span>pending_push_promises: store::Queue<NextAccept>, |
| |
| <span class="doccomment">/// Validate content-length headers |
| </span><span class="kw">pub </span>content_length: ContentLength, |
| } |
| |
| <span class="doccomment">/// State related to validating a stream's content-length |
| </span><span class="attribute">#[derive(Debug)] |
| </span><span class="kw">pub enum </span>ContentLength { |
| Omitted, |
| Head, |
| Remaining(u64), |
| } |
| |
| <span class="attribute">#[derive(Debug)] |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">struct </span>NextAccept; |
| |
| <span class="attribute">#[derive(Debug)] |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">struct </span>NextSend; |
| |
| <span class="attribute">#[derive(Debug)] |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">struct </span>NextSendCapacity; |
| |
| <span class="attribute">#[derive(Debug)] |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">struct </span>NextWindowUpdate; |
| |
| <span class="attribute">#[derive(Debug)] |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">struct </span>NextOpen; |
| |
| <span class="attribute">#[derive(Debug)] |
| </span><span class="kw">pub</span>(<span class="kw">super</span>) <span class="kw">struct </span>NextResetExpire; |
| |
| <span class="kw">impl </span>Stream { |
| <span class="kw">pub fn </span>new(id: StreamId, init_send_window: WindowSize, init_recv_window: WindowSize) -> Stream { |
| <span class="kw">let </span><span class="kw-2">mut </span>send_flow = FlowControl::new(); |
| <span class="kw">let </span><span class="kw-2">mut </span>recv_flow = FlowControl::new(); |
| |
| recv_flow |
| .inc_window(init_recv_window) |
| .expect(<span class="string">"invalid initial receive window"</span>); |
| recv_flow.assign_capacity(init_recv_window); |
| |
| send_flow |
| .inc_window(init_send_window) |
| .expect(<span class="string">"invalid initial send window size"</span>); |
| |
| Stream { |
| id, |
| state: State::default(), |
| ref_count: <span class="number">0</span>, |
| is_counted: <span class="bool-val">false</span>, |
| |
| <span class="comment">// ===== Fields related to sending ===== |
| </span>next_pending_send: <span class="prelude-val">None</span>, |
| is_pending_send: <span class="bool-val">false</span>, |
| send_flow, |
| requested_send_capacity: <span class="number">0</span>, |
| buffered_send_data: <span class="number">0</span>, |
| send_task: <span class="prelude-val">None</span>, |
| pending_send: buffer::Deque::new(), |
| is_pending_send_capacity: <span class="bool-val">false</span>, |
| next_pending_send_capacity: <span class="prelude-val">None</span>, |
| send_capacity_inc: <span class="bool-val">false</span>, |
| is_pending_open: <span class="bool-val">false</span>, |
| next_open: <span class="prelude-val">None</span>, |
| is_pending_push: <span class="bool-val">false</span>, |
| |
| <span class="comment">// ===== Fields related to receiving ===== |
| </span>next_pending_accept: <span class="prelude-val">None</span>, |
| is_pending_accept: <span class="bool-val">false</span>, |
| recv_flow, |
| in_flight_recv_data: <span class="number">0</span>, |
| next_window_update: <span class="prelude-val">None</span>, |
| is_pending_window_update: <span class="bool-val">false</span>, |
| reset_at: <span class="prelude-val">None</span>, |
| next_reset_expire: <span class="prelude-val">None</span>, |
| pending_recv: buffer::Deque::new(), |
| is_recv: <span class="bool-val">true</span>, |
| recv_task: <span class="prelude-val">None</span>, |
| pending_push_promises: store::Queue::new(), |
| content_length: ContentLength::Omitted, |
| } |
| } |
| |
| <span class="doccomment">/// Increment the stream's ref count |
| </span><span class="kw">pub fn </span>ref_inc(<span class="kw-2">&mut </span><span class="self">self</span>) { |
| <span class="macro">assert!</span>(<span class="self">self</span>.ref_count < usize::MAX); |
| <span class="self">self</span>.ref_count += <span class="number">1</span>; |
| } |
| |
| <span class="doccomment">/// Decrements the stream's ref count |
| </span><span class="kw">pub fn </span>ref_dec(<span class="kw-2">&mut </span><span class="self">self</span>) { |
| <span class="macro">assert!</span>(<span class="self">self</span>.ref_count > <span class="number">0</span>); |
| <span class="self">self</span>.ref_count -= <span class="number">1</span>; |
| } |
| |
| <span class="doccomment">/// Returns true if stream is currently being held for some time because of |
| /// a local reset. |
| </span><span class="kw">pub fn </span>is_pending_reset_expiration(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| <span class="self">self</span>.reset_at.is_some() |
| } |
| |
| <span class="doccomment">/// Returns true if frames for this stream are ready to be sent over the wire |
| </span><span class="kw">pub fn </span>is_send_ready(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| <span class="comment">// Why do we check pending_open? |
| // |
| // We allow users to call send_request() which schedules a stream to be pending_open |
| // if there is no room according to the concurrency limit (max_send_streams), and we |
| // also allow data to be buffered for send with send_data() if there is no capacity for |
| // the stream to send the data, which attempts to place the stream in pending_send. |
| // If the stream is not open, we don't want the stream to be scheduled for |
| // execution (pending_send). Note that if the stream is in pending_open, it will be |
| // pushed to pending_send when there is room for an open stream. |
| // |
| // In pending_push we track whether a PushPromise still needs to be sent |
| // from a different stream before we can start sending frames on this one. |
| // This is different from the "open" check because reserved streams don't count |
| // toward the concurrency limit. |
| // See https://httpwg.org/specs/rfc7540.html#rfc.section.5.1.2 |
| </span>!<span class="self">self</span>.is_pending_open && !<span class="self">self</span>.is_pending_push |
| } |
| |
| <span class="doccomment">/// Returns true if the stream is closed |
| </span><span class="kw">pub fn </span>is_closed(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| <span class="comment">// The state has fully transitioned to closed. |
| </span><span class="self">self</span>.state.is_closed() && |
| <span class="comment">// Because outbound frames transition the stream state before being |
| // buffered, we have to ensure that all frames have been flushed. |
| </span><span class="self">self</span>.pending_send.is_empty() && |
| <span class="comment">// Sometimes large data frames are sent out in chunks. After a chunk |
| // of the frame is sent, the remainder is pushed back onto the send |
| // queue to be rescheduled. |
| // |
| // Checking for additional buffered data lets us catch this case. |
| </span><span class="self">self</span>.buffered_send_data == <span class="number">0 |
| </span>} |
| |
| <span class="doccomment">/// Returns true if the stream is no longer in use |
| </span><span class="kw">pub fn </span>is_released(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| <span class="comment">// The stream is closed and fully flushed |
| </span><span class="self">self</span>.is_closed() && |
| <span class="comment">// There are no more outstanding references to the stream |
| </span><span class="self">self</span>.ref_count == <span class="number">0 </span>&& |
| <span class="comment">// The stream is not in any queue |
| </span>!<span class="self">self</span>.is_pending_send && !<span class="self">self</span>.is_pending_send_capacity && |
| !<span class="self">self</span>.is_pending_accept && !<span class="self">self</span>.is_pending_window_update && |
| !<span class="self">self</span>.is_pending_open && <span class="self">self</span>.reset_at.is_none() |
| } |
| |
| <span class="doccomment">/// Returns true when the consumer of the stream has dropped all handles |
| /// (indicating no further interest in the stream) and the stream state is |
| /// not actually closed. |
| /// |
| /// In this case, a reset should be sent. |
| </span><span class="kw">pub fn </span>is_canceled_interest(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| <span class="self">self</span>.ref_count == <span class="number">0 </span>&& !<span class="self">self</span>.state.is_closed() |
| } |
| |
| <span class="doccomment">/// Current available stream send capacity |
| </span><span class="kw">pub fn </span>capacity(<span class="kw-2">&</span><span class="self">self</span>, max_buffer_size: usize) -> WindowSize { |
| <span class="kw">let </span>available = <span class="self">self</span>.send_flow.available().as_size() <span class="kw">as </span>usize; |
| <span class="kw">let </span>buffered = <span class="self">self</span>.buffered_send_data; |
| |
| available.min(max_buffer_size).saturating_sub(buffered) <span class="kw">as </span>WindowSize |
| } |
| |
| <span class="kw">pub fn </span>assign_capacity(<span class="kw-2">&mut </span><span class="self">self</span>, capacity: WindowSize, max_buffer_size: usize) { |
| <span class="kw">let </span>prev_capacity = <span class="self">self</span>.capacity(max_buffer_size); |
| <span class="macro">debug_assert!</span>(capacity > <span class="number">0</span>); |
| <span class="self">self</span>.send_flow.assign_capacity(capacity); |
| |
| <span class="macro">tracing::trace!</span>( |
| <span class="string">" assigned capacity to stream; available={}; buffered={}; id={:?}; max_buffer_size={} prev={}"</span>, |
| <span class="self">self</span>.send_flow.available(), |
| <span class="self">self</span>.buffered_send_data, |
| <span class="self">self</span>.id, |
| max_buffer_size, |
| prev_capacity, |
| ); |
| |
| <span class="kw">if </span>prev_capacity < <span class="self">self</span>.capacity(max_buffer_size) { |
| <span class="self">self</span>.notify_capacity(); |
| } |
| } |
| |
| <span class="kw">pub fn </span>send_data(<span class="kw-2">&mut </span><span class="self">self</span>, len: WindowSize, max_buffer_size: usize) { |
| <span class="kw">let </span>prev_capacity = <span class="self">self</span>.capacity(max_buffer_size); |
| |
| <span class="self">self</span>.send_flow.send_data(len); |
| |
| <span class="comment">// Decrement the stream's buffered data counter |
| </span><span class="macro">debug_assert!</span>(<span class="self">self</span>.buffered_send_data >= len <span class="kw">as </span>usize); |
| <span class="self">self</span>.buffered_send_data -= len <span class="kw">as </span>usize; |
| <span class="self">self</span>.requested_send_capacity -= len; |
| |
| <span class="macro">tracing::trace!</span>( |
| <span class="string">" sent stream data; available={}; buffered={}; id={:?}; max_buffer_size={} prev={}"</span>, |
| <span class="self">self</span>.send_flow.available(), |
| <span class="self">self</span>.buffered_send_data, |
| <span class="self">self</span>.id, |
| max_buffer_size, |
| prev_capacity, |
| ); |
| |
| <span class="kw">if </span>prev_capacity < <span class="self">self</span>.capacity(max_buffer_size) { |
| <span class="self">self</span>.notify_capacity(); |
| } |
| } |
| |
| <span class="doccomment">/// If the capacity was limited because of the max_send_buffer_size, |
| /// then consider waking the send task again... |
| </span><span class="kw">pub fn </span>notify_capacity(<span class="kw-2">&mut </span><span class="self">self</span>) { |
| <span class="self">self</span>.send_capacity_inc = <span class="bool-val">true</span>; |
| <span class="macro">tracing::trace!</span>(<span class="string">" notifying task"</span>); |
| <span class="self">self</span>.notify_send(); |
| } |
| |
| <span class="doccomment">/// Returns `Err` when the decrement cannot be completed due to overflow. |
| </span><span class="kw">pub fn </span>dec_content_length(<span class="kw-2">&mut </span><span class="self">self</span>, len: usize) -> <span class="prelude-ty">Result</span><(), ()> { |
| <span class="kw">match </span><span class="self">self</span>.content_length { |
| ContentLength::Remaining(<span class="kw-2">ref mut </span>rem) => <span class="kw">match </span>rem.checked_sub(len <span class="kw">as </span>u64) { |
| <span class="prelude-val">Some</span>(val) => <span class="kw-2">*</span>rem = val, |
| <span class="prelude-val">None </span>=> <span class="kw">return </span><span class="prelude-val">Err</span>(()), |
| }, |
| ContentLength::Head => { |
| <span class="kw">if </span>len != <span class="number">0 </span>{ |
| <span class="kw">return </span><span class="prelude-val">Err</span>(()); |
| } |
| } |
| <span class="kw">_ </span>=> {} |
| } |
| |
| <span class="prelude-val">Ok</span>(()) |
| } |
| |
| <span class="kw">pub fn </span>ensure_content_length_zero(<span class="kw-2">&</span><span class="self">self</span>) -> <span class="prelude-ty">Result</span><(), ()> { |
| <span class="kw">match </span><span class="self">self</span>.content_length { |
| ContentLength::Remaining(<span class="number">0</span>) => <span class="prelude-val">Ok</span>(()), |
| ContentLength::Remaining(<span class="kw">_</span>) => <span class="prelude-val">Err</span>(()), |
| <span class="kw">_ </span>=> <span class="prelude-val">Ok</span>(()), |
| } |
| } |
| |
| <span class="kw">pub fn </span>notify_send(<span class="kw-2">&mut </span><span class="self">self</span>) { |
| <span class="kw">if let </span><span class="prelude-val">Some</span>(task) = <span class="self">self</span>.send_task.take() { |
| task.wake(); |
| } |
| } |
| |
| <span class="kw">pub fn </span>wait_send(<span class="kw-2">&mut </span><span class="self">self</span>, cx: <span class="kw-2">&</span>Context) { |
| <span class="self">self</span>.send_task = <span class="prelude-val">Some</span>(cx.waker().clone()); |
| } |
| |
| <span class="kw">pub fn </span>notify_recv(<span class="kw-2">&mut </span><span class="self">self</span>) { |
| <span class="kw">if let </span><span class="prelude-val">Some</span>(task) = <span class="self">self</span>.recv_task.take() { |
| task.wake(); |
| } |
| } |
| } |
| |
| <span class="kw">impl </span>store::Next <span class="kw">for </span>NextAccept { |
| <span class="kw">fn </span>next(stream: <span class="kw-2">&</span>Stream) -> <span class="prelude-ty">Option</span><store::Key> { |
| stream.next_pending_accept |
| } |
| |
| <span class="kw">fn </span>set_next(stream: <span class="kw-2">&mut </span>Stream, key: <span class="prelude-ty">Option</span><store::Key>) { |
| stream.next_pending_accept = key; |
| } |
| |
| <span class="kw">fn </span>take_next(stream: <span class="kw-2">&mut </span>Stream) -> <span class="prelude-ty">Option</span><store::Key> { |
| stream.next_pending_accept.take() |
| } |
| |
| <span class="kw">fn </span>is_queued(stream: <span class="kw-2">&</span>Stream) -> bool { |
| stream.is_pending_accept |
| } |
| |
| <span class="kw">fn </span>set_queued(stream: <span class="kw-2">&mut </span>Stream, val: bool) { |
| stream.is_pending_accept = val; |
| } |
| } |
| |
| <span class="kw">impl </span>store::Next <span class="kw">for </span>NextSend { |
| <span class="kw">fn </span>next(stream: <span class="kw-2">&</span>Stream) -> <span class="prelude-ty">Option</span><store::Key> { |
| stream.next_pending_send |
| } |
| |
| <span class="kw">fn </span>set_next(stream: <span class="kw-2">&mut </span>Stream, key: <span class="prelude-ty">Option</span><store::Key>) { |
| stream.next_pending_send = key; |
| } |
| |
| <span class="kw">fn </span>take_next(stream: <span class="kw-2">&mut </span>Stream) -> <span class="prelude-ty">Option</span><store::Key> { |
| stream.next_pending_send.take() |
| } |
| |
| <span class="kw">fn </span>is_queued(stream: <span class="kw-2">&</span>Stream) -> bool { |
| stream.is_pending_send |
| } |
| |
| <span class="kw">fn </span>set_queued(stream: <span class="kw-2">&mut </span>Stream, val: bool) { |
| <span class="kw">if </span>val { |
| <span class="comment">// ensure that stream is not queued for being opened |
| // if it's being put into queue for sending data |
| </span><span class="macro">debug_assert!</span>(!stream.is_pending_open); |
| } |
| stream.is_pending_send = val; |
| } |
| } |
| |
| <span class="kw">impl </span>store::Next <span class="kw">for </span>NextSendCapacity { |
| <span class="kw">fn </span>next(stream: <span class="kw-2">&</span>Stream) -> <span class="prelude-ty">Option</span><store::Key> { |
| stream.next_pending_send_capacity |
| } |
| |
| <span class="kw">fn </span>set_next(stream: <span class="kw-2">&mut </span>Stream, key: <span class="prelude-ty">Option</span><store::Key>) { |
| stream.next_pending_send_capacity = key; |
| } |
| |
| <span class="kw">fn </span>take_next(stream: <span class="kw-2">&mut </span>Stream) -> <span class="prelude-ty">Option</span><store::Key> { |
| stream.next_pending_send_capacity.take() |
| } |
| |
| <span class="kw">fn </span>is_queued(stream: <span class="kw-2">&</span>Stream) -> bool { |
| stream.is_pending_send_capacity |
| } |
| |
| <span class="kw">fn </span>set_queued(stream: <span class="kw-2">&mut </span>Stream, val: bool) { |
| stream.is_pending_send_capacity = val; |
| } |
| } |
| |
| <span class="kw">impl </span>store::Next <span class="kw">for </span>NextWindowUpdate { |
| <span class="kw">fn </span>next(stream: <span class="kw-2">&</span>Stream) -> <span class="prelude-ty">Option</span><store::Key> { |
| stream.next_window_update |
| } |
| |
| <span class="kw">fn </span>set_next(stream: <span class="kw-2">&mut </span>Stream, key: <span class="prelude-ty">Option</span><store::Key>) { |
| stream.next_window_update = key; |
| } |
| |
| <span class="kw">fn </span>take_next(stream: <span class="kw-2">&mut </span>Stream) -> <span class="prelude-ty">Option</span><store::Key> { |
| stream.next_window_update.take() |
| } |
| |
| <span class="kw">fn </span>is_queued(stream: <span class="kw-2">&</span>Stream) -> bool { |
| stream.is_pending_window_update |
| } |
| |
| <span class="kw">fn </span>set_queued(stream: <span class="kw-2">&mut </span>Stream, val: bool) { |
| stream.is_pending_window_update = val; |
| } |
| } |
| |
| <span class="kw">impl </span>store::Next <span class="kw">for </span>NextOpen { |
| <span class="kw">fn </span>next(stream: <span class="kw-2">&</span>Stream) -> <span class="prelude-ty">Option</span><store::Key> { |
| stream.next_open |
| } |
| |
| <span class="kw">fn </span>set_next(stream: <span class="kw-2">&mut </span>Stream, key: <span class="prelude-ty">Option</span><store::Key>) { |
| stream.next_open = key; |
| } |
| |
| <span class="kw">fn </span>take_next(stream: <span class="kw-2">&mut </span>Stream) -> <span class="prelude-ty">Option</span><store::Key> { |
| stream.next_open.take() |
| } |
| |
| <span class="kw">fn </span>is_queued(stream: <span class="kw-2">&</span>Stream) -> bool { |
| stream.is_pending_open |
| } |
| |
| <span class="kw">fn </span>set_queued(stream: <span class="kw-2">&mut </span>Stream, val: bool) { |
| <span class="kw">if </span>val { |
| <span class="comment">// ensure that stream is not queued for being sent |
| // if it's being put into queue for opening the stream |
| </span><span class="macro">debug_assert!</span>(!stream.is_pending_send); |
| } |
| stream.is_pending_open = val; |
| } |
| } |
| |
| <span class="kw">impl </span>store::Next <span class="kw">for </span>NextResetExpire { |
| <span class="kw">fn </span>next(stream: <span class="kw-2">&</span>Stream) -> <span class="prelude-ty">Option</span><store::Key> { |
| stream.next_reset_expire |
| } |
| |
| <span class="kw">fn </span>set_next(stream: <span class="kw-2">&mut </span>Stream, key: <span class="prelude-ty">Option</span><store::Key>) { |
| stream.next_reset_expire = key; |
| } |
| |
| <span class="kw">fn </span>take_next(stream: <span class="kw-2">&mut </span>Stream) -> <span class="prelude-ty">Option</span><store::Key> { |
| stream.next_reset_expire.take() |
| } |
| |
| <span class="kw">fn </span>is_queued(stream: <span class="kw-2">&</span>Stream) -> bool { |
| stream.reset_at.is_some() |
| } |
| |
| <span class="kw">fn </span>set_queued(stream: <span class="kw-2">&mut </span>Stream, val: bool) { |
| <span class="kw">if </span>val { |
| stream.reset_at = <span class="prelude-val">Some</span>(Instant::now()); |
| } <span class="kw">else </span>{ |
| stream.reset_at = <span class="prelude-val">None</span>; |
| } |
| } |
| } |
| |
| <span class="comment">// ===== impl ContentLength ===== |
| |
| </span><span class="kw">impl </span>ContentLength { |
| <span class="kw">pub fn </span>is_head(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| <span class="macro">matches!</span>(<span class="kw-2">*</span><span class="self">self</span>, <span class="self">Self</span>::Head) |
| } |
| } |
| </code></pre></div> |
| </section></div></main><div id="rustdoc-vars" data-root-path="../../../../" data-current-crate="h2" data-themes="ayu,dark,light" data-resource-suffix="" data-rustdoc-version="1.66.0-nightly (5c8bff74b 2022-10-21)" ></div></body></html> |
