| <!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/share.rs`."><meta name="keywords" content="rust, rustlang, rust-lang"><title>share.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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| </pre><pre class="rust"><code><span class="kw">use </span><span class="kw">crate</span>::codec::UserError; |
| <span class="kw">use </span><span class="kw">crate</span>::frame::Reason; |
| <span class="kw">use </span><span class="kw">crate</span>::proto::{<span class="self">self</span>, WindowSize}; |
| |
| <span class="kw">use </span>bytes::{Buf, Bytes}; |
| <span class="kw">use </span>http::HeaderMap; |
| |
| <span class="kw">use </span>std::fmt; |
| <span class="attribute">#[cfg(feature = <span class="string">"stream"</span>)] |
| </span><span class="kw">use </span>std::pin::Pin; |
| <span class="kw">use </span>std::task::{Context, Poll}; |
| |
| <span class="doccomment">/// Sends the body stream and trailers to the remote peer. |
| /// |
| /// # Overview |
| /// |
| /// A `SendStream` is provided by [`SendRequest`] and [`SendResponse`] once the |
| /// HTTP/2 message header has been sent sent. It is used to stream the message |
| /// body and send the message trailers. See method level documentation for more |
| /// details. |
| /// |
| /// The `SendStream` instance is also used to manage outbound flow control. |
| /// |
| /// If a `SendStream` is dropped without explicitly closing the send stream, a |
| /// `RST_STREAM` frame will be sent. This essentially cancels the request / |
| /// response exchange. |
| /// |
| /// The ways to explicitly close the send stream are: |
| /// |
| /// * Set `end_of_stream` to true when calling [`send_request`], |
| /// [`send_response`], or [`send_data`]. |
| /// * Send trailers with [`send_trailers`]. |
| /// * Explicitly reset the stream with [`send_reset`]. |
| /// |
| /// # Flow control |
| /// |
| /// In HTTP/2, data cannot be sent to the remote peer unless there is |
| /// available window capacity on both the stream and the connection. When a data |
| /// frame is sent, both the stream window and the connection window are |
| /// decremented. When the stream level window reaches zero, no further data can |
| /// be sent on that stream. When the connection level window reaches zero, no |
| /// further data can be sent on any stream for that connection. |
| /// |
| /// When the remote peer is ready to receive more data, it sends `WINDOW_UPDATE` |
| /// frames. These frames increment the windows. See the [specification] for more |
| /// details on the principles of HTTP/2 flow control. |
| /// |
| /// The implications for sending data are that the caller **should** ensure that |
| /// both the stream and the connection has available window capacity before |
| /// loading the data to send into memory. The `SendStream` instance provides the |
| /// necessary APIs to perform this logic. This, however, is not an obligation. |
| /// If the caller attempts to send data on a stream when there is no available |
| /// window capacity, the library will buffer the data until capacity becomes |
| /// available, at which point the buffer will be flushed to the connection. |
| /// |
| /// **NOTE**: There is no bound on the amount of data that the library will |
| /// buffer. If you are sending large amounts of data, you really should hook |
| /// into the flow control lifecycle. Otherwise, you risk using up significant |
| /// amounts of memory. |
| /// |
| /// To hook into the flow control lifecycle, the caller signals to the library |
| /// that it intends to send data by calling [`reserve_capacity`], specifying the |
| /// amount of data, in octets, that the caller intends to send. After this, |
| /// `poll_capacity` is used to be notified when the requested capacity is |
| /// assigned to the stream. Once [`poll_capacity`] returns `Ready` with the number |
| /// of octets available to the stream, the caller is able to actually send the |
| /// data using [`send_data`]. |
| /// |
| /// Because there is also a connection level window that applies to **all** |
| /// streams on a connection, when capacity is assigned to a stream (indicated by |
| /// `poll_capacity` returning `Ready`), this capacity is reserved on the |
| /// connection and will **not** be assigned to any other stream. If data is |
| /// never written to the stream, that capacity is effectively lost to other |
| /// streams and this introduces the risk of deadlocking a connection. |
| /// |
| /// To avoid throttling data on a connection, the caller should not reserve |
| /// capacity until ready to send data and once any capacity is assigned to the |
| /// stream, the caller should immediately send data consuming this capacity. |
| /// There is no guarantee as to when the full capacity requested will become |
| /// available. For example, if the caller requests 64 KB of data and 512 bytes |
| /// become available, the caller should immediately send 512 bytes of data. |
| /// |
| /// See [`reserve_capacity`] documentation for more details. |
| /// |
| /// [`SendRequest`]: client/struct.SendRequest.html |
| /// [`SendResponse`]: server/struct.SendResponse.html |
| /// [specification]: http://httpwg.org/specs/rfc7540.html#FlowControl |
| /// [`reserve_capacity`]: #method.reserve_capacity |
| /// [`poll_capacity`]: #method.poll_capacity |
| /// [`send_data`]: #method.send_data |
| /// [`send_request`]: client/struct.SendRequest.html#method.send_request |
| /// [`send_response`]: server/struct.SendResponse.html#method.send_response |
| /// [`send_data`]: #method.send_data |
| /// [`send_trailers`]: #method.send_trailers |
| /// [`send_reset`]: #method.send_reset |
| </span><span class="attribute">#[derive(Debug)] |
| </span><span class="kw">pub struct </span>SendStream<B> { |
| inner: proto::StreamRef<B>, |
| } |
| |
| <span class="doccomment">/// A stream identifier, as described in [Section 5.1.1] of RFC 7540. |
| /// |
| /// Streams are identified with an unsigned 31-bit integer. Streams |
| /// initiated by a client MUST use odd-numbered stream identifiers; those |
| /// initiated by the server MUST use even-numbered stream identifiers. A |
| /// stream identifier of zero (0x0) is used for connection control |
| /// messages; the stream identifier of zero cannot be used to establish a |
| /// new stream. |
| /// |
| /// [Section 5.1.1]: https://tools.ietf.org/html/rfc7540#section-5.1.1 |
| </span><span class="attribute">#[derive(Debug, Clone, Copy, Eq, PartialEq, Hash)] |
| </span><span class="kw">pub struct </span>StreamId(u32); |
| |
| <span class="kw">impl </span>From<StreamId> <span class="kw">for </span>u32 { |
| <span class="kw">fn </span>from(src: StreamId) -> <span class="self">Self </span>{ |
| src.<span class="number">0 |
| </span>} |
| } |
| |
| <span class="doccomment">/// Receives the body stream and trailers from the remote peer. |
| /// |
| /// A `RecvStream` is provided by [`client::ResponseFuture`] and |
| /// [`server::Connection`] with the received HTTP/2 message head (the response |
| /// and request head respectively). |
| /// |
| /// A `RecvStream` instance is used to receive the streaming message body and |
| /// any trailers from the remote peer. It is also used to manage inbound flow |
| /// control. |
| /// |
| /// See method level documentation for more details on receiving data. See |
| /// [`FlowControl`] for more details on inbound flow control. |
| /// |
| /// [`client::ResponseFuture`]: client/struct.ResponseFuture.html |
| /// [`server::Connection`]: server/struct.Connection.html |
| /// [`FlowControl`]: struct.FlowControl.html |
| /// [`Stream`]: https://docs.rs/futures/0.1/futures/stream/trait.Stream.html |
| </span><span class="attribute">#[must_use = <span class="string">"streams do nothing unless polled"</span>] |
| </span><span class="kw">pub struct </span>RecvStream { |
| inner: FlowControl, |
| } |
| |
| <span class="doccomment">/// A handle to release window capacity to a remote stream. |
| /// |
| /// This type allows the caller to manage inbound data [flow control]. The |
| /// caller is expected to call [`release_capacity`] after dropping data frames. |
| /// |
| /// # Overview |
| /// |
| /// Each stream has a window size. This window size is the maximum amount of |
| /// inbound data that can be in-flight. In-flight data is defined as data that |
| /// has been received, but not yet released. |
| /// |
| /// When a stream is created, the window size is set to the connection's initial |
| /// window size value. When a data frame is received, the window size is then |
| /// decremented by size of the data frame before the data is provided to the |
| /// caller. As the caller finishes using the data, [`release_capacity`] must be |
| /// called. This will then increment the window size again, allowing the peer to |
| /// send more data. |
| /// |
| /// There is also a connection level window as well as the stream level window. |
| /// Received data counts against the connection level window as well and calls |
| /// to [`release_capacity`] will also increment the connection level window. |
| /// |
| /// # Sending `WINDOW_UPDATE` frames |
| /// |
| /// `WINDOW_UPDATE` frames will not be sent out for **every** call to |
| /// `release_capacity`, as this would end up slowing down the protocol. Instead, |
| /// `h2` waits until the window size is increased to a certain threshold and |
| /// then sends out a single `WINDOW_UPDATE` frame representing all the calls to |
| /// `release_capacity` since the last `WINDOW_UPDATE` frame. |
| /// |
| /// This essentially batches window updating. |
| /// |
| /// # Scenarios |
| /// |
| /// Following is a basic scenario with an HTTP/2 connection containing a |
| /// single active stream. |
| /// |
| /// * A new stream is activated. The receive window is initialized to 1024 (the |
| /// value of the initial window size for this connection). |
| /// * A `DATA` frame is received containing a payload of 600 bytes. |
| /// * The receive window size is reduced to 424 bytes. |
| /// * [`release_capacity`] is called with 200. |
| /// * The receive window size is now 624 bytes. The peer may send no more than |
| /// this. |
| /// * A `DATA` frame is received with a payload of 624 bytes. |
| /// * The window size is now 0 bytes. The peer may not send any more data. |
| /// * [`release_capacity`] is called with 1024. |
| /// * The receive window size is now 1024 bytes. The peer may now send more |
| /// data. |
| /// |
| /// [flow control]: ../index.html#flow-control |
| /// [`release_capacity`]: struct.FlowControl.html#method.release_capacity |
| </span><span class="attribute">#[derive(Clone, Debug)] |
| </span><span class="kw">pub struct </span>FlowControl { |
| inner: proto::OpaqueStreamRef, |
| } |
| |
| <span class="doccomment">/// A handle to send and receive PING frames with the peer. |
| </span><span class="comment">// NOT Clone on purpose |
| </span><span class="kw">pub struct </span>PingPong { |
| inner: proto::UserPings, |
| } |
| |
| <span class="doccomment">/// Sent via [`PingPong`][] to send a PING frame to a peer. |
| /// |
| /// [`PingPong`]: struct.PingPong.html |
| </span><span class="kw">pub struct </span>Ping { |
| _p: (), |
| } |
| |
| <span class="doccomment">/// Received via [`PingPong`][] when a peer acknowledges a [`Ping`][]. |
| /// |
| /// [`PingPong`]: struct.PingPong.html |
| /// [`Ping`]: struct.Ping.html |
| </span><span class="kw">pub struct </span>Pong { |
| _p: (), |
| } |
| |
| <span class="comment">// ===== impl SendStream ===== |
| |
| </span><span class="kw">impl</span><B: Buf> SendStream<B> { |
| <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>new(inner: proto::StreamRef<B>) -> <span class="self">Self </span>{ |
| SendStream { inner } |
| } |
| |
| <span class="doccomment">/// Requests capacity to send data. |
| /// |
| /// This function is used to express intent to send data. This requests |
| /// connection level capacity. Once the capacity is available, it is |
| /// assigned to the stream and not reused by other streams. |
| /// |
| /// This function may be called repeatedly. The `capacity` argument is the |
| /// **total** amount of requested capacity. Sequential calls to |
| /// `reserve_capacity` are *not* additive. Given the following: |
| /// |
| /// ```rust |
| /// # use h2::*; |
| /// # fn doc(mut send_stream: SendStream<&'static [u8]>) { |
| /// send_stream.reserve_capacity(100); |
| /// send_stream.reserve_capacity(200); |
| /// # } |
| /// ``` |
| /// |
| /// After the second call to `reserve_capacity`, the *total* requested |
| /// capacity will be 200. |
| /// |
| /// `reserve_capacity` is also used to cancel previous capacity requests. |
| /// Given the following: |
| /// |
| /// ```rust |
| /// # use h2::*; |
| /// # fn doc(mut send_stream: SendStream<&'static [u8]>) { |
| /// send_stream.reserve_capacity(100); |
| /// send_stream.reserve_capacity(0); |
| /// # } |
| /// ``` |
| /// |
| /// After the second call to `reserve_capacity`, the *total* requested |
| /// capacity will be 0, i.e. there is no requested capacity for the stream. |
| /// |
| /// If `reserve_capacity` is called with a lower value than the amount of |
| /// capacity **currently** assigned to the stream, this capacity will be |
| /// returned to the connection to be re-assigned to other streams. |
| /// |
| /// Also, the amount of capacity that is reserved gets decremented as data |
| /// is sent. For example: |
| /// |
| /// ```rust |
| /// # use h2::*; |
| /// # async fn doc(mut send_stream: SendStream<&'static [u8]>) { |
| /// send_stream.reserve_capacity(100); |
| /// |
| /// send_stream.send_data(b"hello", false).unwrap(); |
| /// // At this point, the total amount of requested capacity is 95 bytes. |
| /// |
| /// // Calling `reserve_capacity` with `100` again essentially requests an |
| /// // additional 5 bytes. |
| /// send_stream.reserve_capacity(100); |
| /// # } |
| /// ``` |
| /// |
| /// See [Flow control](struct.SendStream.html#flow-control) for an overview |
| /// of how send flow control works. |
| </span><span class="kw">pub fn </span>reserve_capacity(<span class="kw-2">&mut </span><span class="self">self</span>, capacity: usize) { |
| <span class="comment">// TODO: Check for overflow |
| </span><span class="self">self</span>.inner.reserve_capacity(capacity <span class="kw">as </span>WindowSize) |
| } |
| |
| <span class="doccomment">/// Returns the stream's current send capacity. |
| /// |
| /// This allows the caller to check the current amount of available capacity |
| /// before sending data. |
| </span><span class="kw">pub fn </span>capacity(<span class="kw-2">&</span><span class="self">self</span>) -> usize { |
| <span class="self">self</span>.inner.capacity() <span class="kw">as </span>usize |
| } |
| |
| <span class="doccomment">/// Requests to be notified when the stream's capacity increases. |
| /// |
| /// Before calling this, capacity should be requested with |
| /// `reserve_capacity`. Once capacity is requested, the connection will |
| /// assign capacity to the stream **as it becomes available**. There is no |
| /// guarantee as to when and in what increments capacity gets assigned to |
| /// the stream. |
| /// |
| /// To get notified when the available capacity increases, the caller calls |
| /// `poll_capacity`, which returns `Ready(Some(n))` when `n` has been |
| /// increased by the connection. Note that `n` here represents the **total** |
| /// amount of assigned capacity at that point in time. It is also possible |
| /// that `n` is lower than the previous call if, since then, the caller has |
| /// sent data. |
| </span><span class="kw">pub fn </span>poll_capacity(<span class="kw-2">&mut </span><span class="self">self</span>, cx: <span class="kw-2">&mut </span>Context) -> Poll<<span class="prelude-ty">Option</span><<span class="prelude-ty">Result</span><usize, <span class="kw">crate</span>::Error>>> { |
| <span class="self">self</span>.inner |
| .poll_capacity(cx) |
| .map_ok(|w| w <span class="kw">as </span>usize) |
| .map_err(Into::into) |
| } |
| |
| <span class="doccomment">/// Sends a single data frame to the remote peer. |
| /// |
| /// This function may be called repeatedly as long as `end_of_stream` is set |
| /// to `false`. Setting `end_of_stream` to `true` sets the end stream flag |
| /// on the data frame. Any further calls to `send_data` or `send_trailers` |
| /// will return an [`Error`]. |
| /// |
| /// `send_data` can be called without reserving capacity. In this case, the |
| /// data is buffered and the capacity is implicitly requested. Once the |
| /// capacity becomes available, the data is flushed to the connection. |
| /// However, this buffering is unbounded. As such, sending large amounts of |
| /// data without reserving capacity before hand could result in large |
| /// amounts of data being buffered in memory. |
| /// |
| /// [`Error`]: struct.Error.html |
| </span><span class="kw">pub fn </span>send_data(<span class="kw-2">&mut </span><span class="self">self</span>, data: B, end_of_stream: bool) -> <span class="prelude-ty">Result</span><(), <span class="kw">crate</span>::Error> { |
| <span class="self">self</span>.inner |
| .send_data(data, end_of_stream) |
| .map_err(Into::into) |
| } |
| |
| <span class="doccomment">/// Sends trailers to the remote peer. |
| /// |
| /// Sending trailers implicitly closes the send stream. Once the send stream |
| /// is closed, no more data can be sent. |
| </span><span class="kw">pub fn </span>send_trailers(<span class="kw-2">&mut </span><span class="self">self</span>, trailers: HeaderMap) -> <span class="prelude-ty">Result</span><(), <span class="kw">crate</span>::Error> { |
| <span class="self">self</span>.inner.send_trailers(trailers).map_err(Into::into) |
| } |
| |
| <span class="doccomment">/// Resets the stream. |
| /// |
| /// This cancels the request / response exchange. If the response has not |
| /// yet been received, the associated `ResponseFuture` will return an |
| /// [`Error`] to reflect the canceled exchange. |
| /// |
| /// [`Error`]: struct.Error.html |
| </span><span class="kw">pub fn </span>send_reset(<span class="kw-2">&mut </span><span class="self">self</span>, reason: Reason) { |
| <span class="self">self</span>.inner.send_reset(reason) |
| } |
| |
| <span class="doccomment">/// Polls to be notified when the client resets this stream. |
| /// |
| /// If stream is still open, this returns `Poll::Pending`, and |
| /// registers the task to be notified if a `RST_STREAM` is received. |
| /// |
| /// If a `RST_STREAM` frame is received for this stream, calling this |
| /// method will yield the `Reason` for the reset. |
| /// |
| /// # Error |
| /// |
| /// If connection sees an error, this returns that error instead of a |
| /// `Reason`. |
| </span><span class="kw">pub fn </span>poll_reset(<span class="kw-2">&mut </span><span class="self">self</span>, cx: <span class="kw-2">&mut </span>Context) -> Poll<<span class="prelude-ty">Result</span><Reason, <span class="kw">crate</span>::Error>> { |
| <span class="self">self</span>.inner.poll_reset(cx, proto::PollReset::Streaming) |
| } |
| |
| <span class="doccomment">/// Returns the stream ID of this `SendStream`. |
| /// |
| /// # Panics |
| /// |
| /// If the lock on the stream store has been poisoned. |
| </span><span class="kw">pub fn </span>stream_id(<span class="kw-2">&</span><span class="self">self</span>) -> StreamId { |
| StreamId::from_internal(<span class="self">self</span>.inner.stream_id()) |
| } |
| } |
| |
| <span class="comment">// ===== impl StreamId ===== |
| |
| </span><span class="kw">impl </span>StreamId { |
| <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>from_internal(id: <span class="kw">crate</span>::frame::StreamId) -> <span class="self">Self </span>{ |
| StreamId(id.into()) |
| } |
| |
| <span class="doccomment">/// Returns the `u32` corresponding to this `StreamId` |
| /// |
| /// # Note |
| /// |
| /// This is the same as the `From<StreamId>` implementation, but |
| /// included as an inherent method because that implementation doesn't |
| /// appear in rustdocs, as well as a way to force the type instead of |
| /// relying on inference. |
| </span><span class="kw">pub fn </span>as_u32(<span class="kw-2">&</span><span class="self">self</span>) -> u32 { |
| (<span class="kw-2">*</span><span class="self">self</span>).into() |
| } |
| } |
| <span class="comment">// ===== impl RecvStream ===== |
| |
| </span><span class="kw">impl </span>RecvStream { |
| <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>new(inner: FlowControl) -> <span class="self">Self </span>{ |
| RecvStream { inner } |
| } |
| |
| <span class="doccomment">/// Get the next data frame. |
| </span><span class="kw">pub async fn </span>data(<span class="kw-2">&mut </span><span class="self">self</span>) -> <span class="prelude-ty">Option</span><<span class="prelude-ty">Result</span><Bytes, <span class="kw">crate</span>::Error>> { |
| futures_util::future::poll_fn(<span class="kw">move </span>|cx| <span class="self">self</span>.poll_data(cx)).<span class="kw">await |
| </span>} |
| |
| <span class="doccomment">/// Get optional trailers for this stream. |
| </span><span class="kw">pub async fn </span>trailers(<span class="kw-2">&mut </span><span class="self">self</span>) -> <span class="prelude-ty">Result</span><<span class="prelude-ty">Option</span><HeaderMap>, <span class="kw">crate</span>::Error> { |
| futures_util::future::poll_fn(<span class="kw">move </span>|cx| <span class="self">self</span>.poll_trailers(cx)).<span class="kw">await |
| </span>} |
| |
| <span class="doccomment">/// Poll for the next data frame. |
| </span><span class="kw">pub fn </span>poll_data(<span class="kw-2">&mut </span><span class="self">self</span>, cx: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>) -> Poll<<span class="prelude-ty">Option</span><<span class="prelude-ty">Result</span><Bytes, <span class="kw">crate</span>::Error>>> { |
| <span class="self">self</span>.inner.inner.poll_data(cx).map_err(Into::into) |
| } |
| |
| <span class="attribute">#[doc(hidden)] |
| </span><span class="kw">pub fn </span>poll_trailers( |
| <span class="kw-2">&mut </span><span class="self">self</span>, |
| cx: <span class="kw-2">&mut </span>Context, |
| ) -> Poll<<span class="prelude-ty">Result</span><<span class="prelude-ty">Option</span><HeaderMap>, <span class="kw">crate</span>::Error>> { |
| <span class="kw">match </span><span class="macro">ready!</span>(<span class="self">self</span>.inner.inner.poll_trailers(cx)) { |
| <span class="prelude-val">Some</span>(<span class="prelude-val">Ok</span>(map)) => Poll::Ready(<span class="prelude-val">Ok</span>(<span class="prelude-val">Some</span>(map))), |
| <span class="prelude-val">Some</span>(<span class="prelude-val">Err</span>(e)) => Poll::Ready(<span class="prelude-val">Err</span>(e.into())), |
| <span class="prelude-val">None </span>=> Poll::Ready(<span class="prelude-val">Ok</span>(<span class="prelude-val">None</span>)), |
| } |
| } |
| |
| <span class="doccomment">/// Returns true if the receive half has reached the end of stream. |
| /// |
| /// A return value of `true` means that calls to `poll` and `poll_trailers` |
| /// will both return `None`. |
| </span><span class="kw">pub fn </span>is_end_stream(<span class="kw-2">&</span><span class="self">self</span>) -> bool { |
| <span class="self">self</span>.inner.inner.is_end_stream() |
| } |
| |
| <span class="doccomment">/// Get a mutable reference to this stream's `FlowControl`. |
| /// |
| /// It can be used immediately, or cloned to be used later. |
| </span><span class="kw">pub fn </span>flow_control(<span class="kw-2">&mut </span><span class="self">self</span>) -> <span class="kw-2">&mut </span>FlowControl { |
| <span class="kw-2">&mut </span><span class="self">self</span>.inner |
| } |
| |
| <span class="doccomment">/// Returns the stream ID of this stream. |
| /// |
| /// # Panics |
| /// |
| /// If the lock on the stream store has been poisoned. |
| </span><span class="kw">pub fn </span>stream_id(<span class="kw-2">&</span><span class="self">self</span>) -> StreamId { |
| <span class="self">self</span>.inner.stream_id() |
| } |
| } |
| |
| <span class="attribute">#[cfg(feature = <span class="string">"stream"</span>)] |
| </span><span class="kw">impl </span>futures_core::Stream <span class="kw">for </span>RecvStream { |
| <span class="kw">type </span>Item = <span class="prelude-ty">Result</span><Bytes, <span class="kw">crate</span>::Error>; |
| |
| <span class="kw">fn </span>poll_next(<span class="kw-2">mut </span><span class="self">self</span>: Pin<<span class="kw-2">&mut </span><span class="self">Self</span>>, cx: <span class="kw-2">&mut </span>Context<<span class="lifetime">'_</span>>) -> Poll<<span class="prelude-ty">Option</span><<span class="self">Self</span>::Item>> { |
| <span class="self">self</span>.poll_data(cx) |
| } |
| } |
| |
| <span class="kw">impl </span>fmt::Debug <span class="kw">for </span>RecvStream { |
| <span class="kw">fn </span>fmt(<span class="kw-2">&</span><span class="self">self</span>, fmt: <span class="kw-2">&mut </span>fmt::Formatter) -> fmt::Result { |
| fmt.debug_struct(<span class="string">"RecvStream"</span>) |
| .field(<span class="string">"inner"</span>, <span class="kw-2">&</span><span class="self">self</span>.inner) |
| .finish() |
| } |
| } |
| |
| <span class="kw">impl </span>Drop <span class="kw">for </span>RecvStream { |
| <span class="kw">fn </span>drop(<span class="kw-2">&mut </span><span class="self">self</span>) { |
| <span class="comment">// Eagerly clear any received DATA frames now, since its no longer |
| // possible to retrieve them. However, this will be called |
| // again once *all* stream refs have been dropped, since |
| // this won't send a RST_STREAM frame, in case the user wishes to |
| // still *send* DATA. |
| </span><span class="self">self</span>.inner.inner.clear_recv_buffer(); |
| } |
| } |
| |
| <span class="comment">// ===== impl FlowControl ===== |
| |
| </span><span class="kw">impl </span>FlowControl { |
| <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>new(inner: proto::OpaqueStreamRef) -> <span class="self">Self </span>{ |
| FlowControl { inner } |
| } |
| |
| <span class="doccomment">/// Returns the stream ID of the stream whose capacity will |
| /// be released by this `FlowControl`. |
| </span><span class="kw">pub fn </span>stream_id(<span class="kw-2">&</span><span class="self">self</span>) -> StreamId { |
| StreamId::from_internal(<span class="self">self</span>.inner.stream_id()) |
| } |
| |
| <span class="doccomment">/// Get the current available capacity of data this stream *could* receive. |
| </span><span class="kw">pub fn </span>available_capacity(<span class="kw-2">&</span><span class="self">self</span>) -> isize { |
| <span class="self">self</span>.inner.available_recv_capacity() |
| } |
| |
| <span class="doccomment">/// Get the currently *used* capacity for this stream. |
| /// |
| /// This is the amount of bytes that can be released back to the remote. |
| </span><span class="kw">pub fn </span>used_capacity(<span class="kw-2">&</span><span class="self">self</span>) -> usize { |
| <span class="self">self</span>.inner.used_recv_capacity() <span class="kw">as </span>usize |
| } |
| |
| <span class="doccomment">/// Release window capacity back to remote stream. |
| /// |
| /// This releases capacity back to the stream level and the connection level |
| /// windows. Both window sizes will be increased by `sz`. |
| /// |
| /// See [struct level] documentation for more details. |
| /// |
| /// # Errors |
| /// |
| /// This function errors if increasing the receive window size by `sz` would |
| /// result in a window size greater than the target window size. In other |
| /// words, the caller cannot release more capacity than data has been |
| /// received. If 1024 bytes of data have been received, at most 1024 bytes |
| /// can be released. |
| /// |
| /// [struct level]: # |
| </span><span class="kw">pub fn </span>release_capacity(<span class="kw-2">&mut </span><span class="self">self</span>, sz: usize) -> <span class="prelude-ty">Result</span><(), <span class="kw">crate</span>::Error> { |
| <span class="kw">if </span>sz > proto::MAX_WINDOW_SIZE <span class="kw">as </span>usize { |
| <span class="kw">return </span><span class="prelude-val">Err</span>(UserError::ReleaseCapacityTooBig.into()); |
| } |
| <span class="self">self</span>.inner |
| .release_capacity(sz <span class="kw">as </span>proto::WindowSize) |
| .map_err(Into::into) |
| } |
| } |
| |
| <span class="comment">// ===== impl PingPong ===== |
| |
| </span><span class="kw">impl </span>PingPong { |
| <span class="kw">pub</span>(<span class="kw">crate</span>) <span class="kw">fn </span>new(inner: proto::UserPings) -> <span class="self">Self </span>{ |
| PingPong { inner } |
| } |
| |
| <span class="doccomment">/// Send a PING frame and wait for the peer to send the pong. |
| </span><span class="kw">pub async fn </span>ping(<span class="kw-2">&mut </span><span class="self">self</span>, ping: Ping) -> <span class="prelude-ty">Result</span><Pong, <span class="kw">crate</span>::Error> { |
| <span class="self">self</span>.send_ping(ping)<span class="question-mark">?</span>; |
| futures_util::future::poll_fn(|cx| <span class="self">self</span>.poll_pong(cx)).<span class="kw">await |
| </span>} |
| |
| <span class="attribute">#[doc(hidden)] |
| </span><span class="kw">pub fn </span>send_ping(<span class="kw-2">&mut </span><span class="self">self</span>, ping: Ping) -> <span class="prelude-ty">Result</span><(), <span class="kw">crate</span>::Error> { |
| <span class="comment">// Passing a `Ping` here is just to be forwards-compatible with |
| // eventually allowing choosing a ping payload. For now, we can |
| // just ignore it. |
| </span><span class="kw">let _ </span>= ping; |
| |
| <span class="self">self</span>.inner.send_ping().map_err(|err| <span class="kw">match </span>err { |
| <span class="prelude-val">Some</span>(err) => err.into(), |
| <span class="prelude-val">None </span>=> UserError::SendPingWhilePending.into(), |
| }) |
| } |
| |
| <span class="attribute">#[doc(hidden)] |
| </span><span class="kw">pub fn </span>poll_pong(<span class="kw-2">&mut </span><span class="self">self</span>, cx: <span class="kw-2">&mut </span>Context) -> Poll<<span class="prelude-ty">Result</span><Pong, <span class="kw">crate</span>::Error>> { |
| <span class="macro">ready!</span>(<span class="self">self</span>.inner.poll_pong(cx))<span class="question-mark">?</span>; |
| Poll::Ready(<span class="prelude-val">Ok</span>(Pong { _p: () })) |
| } |
| } |
| |
| <span class="kw">impl </span>fmt::Debug <span class="kw">for </span>PingPong { |
| <span class="kw">fn </span>fmt(<span class="kw-2">&</span><span class="self">self</span>, fmt: <span class="kw-2">&mut </span>fmt::Formatter) -> fmt::Result { |
| fmt.debug_struct(<span class="string">"PingPong"</span>).finish() |
| } |
| } |
| |
| <span class="comment">// ===== impl Ping ===== |
| |
| </span><span class="kw">impl </span>Ping { |
| <span class="doccomment">/// Creates a new opaque `Ping` to be sent via a [`PingPong`][]. |
| /// |
| /// The payload is "opaque", such that it shouldn't be depended on. |
| /// |
| /// [`PingPong`]: struct.PingPong.html |
| </span><span class="kw">pub fn </span>opaque() -> Ping { |
| Ping { _p: () } |
| } |
| } |
| |
| <span class="kw">impl </span>fmt::Debug <span class="kw">for </span>Ping { |
| <span class="kw">fn </span>fmt(<span class="kw-2">&</span><span class="self">self</span>, fmt: <span class="kw-2">&mut </span>fmt::Formatter) -> fmt::Result { |
| fmt.debug_struct(<span class="string">"Ping"</span>).finish() |
| } |
| } |
| |
| <span class="comment">// ===== impl Pong ===== |
| |
| </span><span class="kw">impl </span>fmt::Debug <span class="kw">for </span>Pong { |
| <span class="kw">fn </span>fmt(<span class="kw-2">&</span><span class="self">self</span>, fmt: <span class="kw-2">&mut </span>fmt::Formatter) -> fmt::Result { |
| fmt.debug_struct(<span class="string">"Pong"</span>).finish() |
| } |
| } |
| </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> |
