Adding upstream version 110.0.1.upstream/110.0.1upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 537 insertions, 0 deletions

diff --git a/third_party/rust/tokio/src/lib.rs b/third_party/rust/tokio/src/lib.rs
new file mode 100644
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+++ b/third_party/rust/tokio/src/lib.rs
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+#![allow(
+    clippy::cognitive_complexity,
+    clippy::large_enum_variant,
+    clippy::needless_doctest_main
+)]
+#![warn(
+    missing_debug_implementations,
+    missing_docs,
+    rust_2018_idioms,
+    unreachable_pub
+)]
+#![deny(unused_must_use)]
+#![doc(test(
+    no_crate_inject,
+    attr(deny(warnings, rust_2018_idioms), allow(dead_code, unused_variables))
+))]
+#![cfg_attr(docsrs, feature(doc_cfg))]
+#![cfg_attr(docsrs, allow(unused_attributes))]
+
+//! A runtime for writing reliable network applications without compromising speed.
+//!
+//! Tokio is an event-driven, non-blocking I/O platform for writing asynchronous
+//! applications with the Rust programming language. At a high level, it
+//! provides a few major components:
+//!
+//! * Tools for [working with asynchronous tasks][tasks], including
+//!   [synchronization primitives and channels][sync] and [timeouts, sleeps, and
+//!   intervals][time].
+//! * APIs for [performing asynchronous I/O][io], including [TCP and UDP][net] sockets,
+//!   [filesystem][fs] operations, and [process] and [signal] management.
+//! * A [runtime] for executing asynchronous code, including a task scheduler,
+//!   an I/O driver backed by the operating system's event queue (epoll, kqueue,
+//!   IOCP, etc...), and a high performance timer.
+//!
+//! Guide level documentation is found on the [website].
+//!
+//! [tasks]: #working-with-tasks
+//! [sync]: crate::sync
+//! [time]: crate::time
+//! [io]: #asynchronous-io
+//! [net]: crate::net
+//! [fs]: crate::fs
+//! [process]: crate::process
+//! [signal]: crate::signal
+//! [fs]: crate::fs
+//! [runtime]: crate::runtime
+//! [website]: https://tokio.rs/tokio/tutorial
+//!
+//! # A Tour of Tokio
+//!
+//! Tokio consists of a number of modules that provide a range of functionality
+//! essential for implementing asynchronous applications in Rust. In this
+//! section, we will take a brief tour of Tokio, summarizing the major APIs and
+//! their uses.
+//!
+//! The easiest way to get started is to enable all features. Do this by
+//! enabling the `full` feature flag:
+//!
+//! ```toml
+//! tokio = { version = "1", features = ["full"] }
+//! ```
+//!
+//! ### Authoring applications
+//!
+//! Tokio is great for writing applications and most users in this case shouldn't
+//! worry too much about what features they should pick. If you're unsure, we suggest
+//! going with `full` to ensure that you don't run into any road blocks while you're
+//! building your application.
+//!
+//! #### Example
+//!
+//! This example shows the quickest way to get started with Tokio.
+//!
+//! ```toml
+//! tokio = { version = "1", features = ["full"] }
+//! ```
+//!
+//! ### Authoring libraries
+//!
+//! As a library author your goal should be to provide the lightest weight crate
+//! that is based on Tokio. To achieve this you should ensure that you only enable
+//! the features you need. This allows users to pick up your crate without having
+//! to enable unnecessary features.
+//!
+//! #### Example
+//!
+//! This example shows how you may want to import features for a library that just
+//! needs to `tokio::spawn` and use a `TcpStream`.
+//!
+//! ```toml
+//! tokio = { version = "1", features = ["rt", "net"] }
+//! ```
+//!
+//! ## Working With Tasks
+//!
+//! Asynchronous programs in Rust are based around lightweight, non-blocking
+//! units of execution called [_tasks_][tasks]. The [`tokio::task`] module provides
+//! important tools for working with tasks:
+//!
+//! * The [`spawn`] function and [`JoinHandle`] type, for scheduling a new task
+//!   on the Tokio runtime and awaiting the output of a spawned task, respectively,
+//! * Functions for [running blocking operations][blocking] in an asynchronous
+//!   task context.
+//!
+//! The [`tokio::task`] module is present only when the "rt" feature flag
+//! is enabled.
+//!
+//! [tasks]: task/index.html#what-are-tasks
+//! [`tokio::task`]: crate::task
+//! [`spawn`]: crate::task::spawn()
+//! [`JoinHandle`]: crate::task::JoinHandle
+//! [blocking]: task/index.html#blocking-and-yielding
+//!
+//! The [`tokio::sync`] module contains synchronization primitives to use when
+//! needing to communicate or share data. These include:
+//!
+//! * channels ([`oneshot`], [`mpsc`], and [`watch`]), for sending values
+//!   between tasks,
+//! * a non-blocking [`Mutex`], for controlling access to a shared, mutable
+//!   value,
+//! * an asynchronous [`Barrier`] type, for multiple tasks to synchronize before
+//!   beginning a computation.
+//!
+//! The `tokio::sync` module is present only when the "sync" feature flag is
+//! enabled.
+//!
+//! [`tokio::sync`]: crate::sync
+//! [`Mutex`]: crate::sync::Mutex
+//! [`Barrier`]: crate::sync::Barrier
+//! [`oneshot`]: crate::sync::oneshot
+//! [`mpsc`]: crate::sync::mpsc
+//! [`watch`]: crate::sync::watch
+//!
+//! The [`tokio::time`] module provides utilities for tracking time and
+//! scheduling work. This includes functions for setting [timeouts][timeout] for
+//! tasks, [sleeping][sleep] work to run in the future, or [repeating an operation at an
+//! interval][interval].
+//!
+//! In order to use `tokio::time`, the "time" feature flag must be enabled.
+//!
+//! [`tokio::time`]: crate::time
+//! [sleep]: crate::time::sleep()
+//! [interval]: crate::time::interval()
+//! [timeout]: crate::time::timeout()
+//!
+//! Finally, Tokio provides a _runtime_ for executing asynchronous tasks. Most
+//! applications can use the [`#[tokio::main]`][main] macro to run their code on the
+//! Tokio runtime. However, this macro provides only basic configuration options. As
+//! an alternative, the [`tokio::runtime`] module provides more powerful APIs for configuring
+//! and managing runtimes. You should use that module if the `#[tokio::main]` macro doesn't
+//! provide the functionality you need.
+//!
+//! Using the runtime requires the "rt" or "rt-multi-thread" feature flags, to
+//! enable the basic [single-threaded scheduler][rt] and the [thread-pool
+//! scheduler][rt-multi-thread], respectively. See the [`runtime` module
+//! documentation][rt-features] for details. In addition, the "macros" feature
+//! flag enables the `#[tokio::main]` and `#[tokio::test]` attributes.
+//!
+//! [main]: attr.main.html
+//! [`tokio::runtime`]: crate::runtime
+//! [`Builder`]: crate::runtime::Builder
+//! [`Runtime`]: crate::runtime::Runtime
+//! [rt]: runtime/index.html#current-thread-scheduler
+//! [rt-multi-thread]: runtime/index.html#multi-thread-scheduler
+//! [rt-features]: runtime/index.html#runtime-scheduler
+//!
+//! ## CPU-bound tasks and blocking code
+//!
+//! Tokio is able to concurrently run many tasks on a few threads by repeatedly
+//! swapping the currently running task on each thread. However, this kind of
+//! swapping can only happen at `.await` points, so code that spends a long time
+//! without reaching an `.await` will prevent other tasks from running. To
+//! combat this, Tokio provides two kinds of threads: Core threads and blocking
+//! threads. The core threads are where all asynchronous code runs, and Tokio
+//! will by default spawn one for each CPU core. The blocking threads are
+//! spawned on demand, can be used to run blocking code that would otherwise
+//! block other tasks from running and are kept alive when not used for a certain
+//! amount of time which can be configured with [`thread_keep_alive`].
+//! Since it is not possible for Tokio to swap out blocking tasks, like it
+//! can do with asynchronous code, the upper limit on the number of blocking
+//! threads is very large. These limits can be configured on the [`Builder`].
+//!
+//! To spawn a blocking task, you should use the [`spawn_blocking`] function.
+//!
+//! [`Builder`]: crate::runtime::Builder
+//! [`spawn_blocking`]: crate::task::spawn_blocking()
+//! [`thread_keep_alive`]: crate::runtime::Builder::thread_keep_alive()
+//!
+//! ```
+//! #[tokio::main]
+//! async fn main() {
+//!     // This is running on a core thread.
+//!
+//!     let blocking_task = tokio::task::spawn_blocking(|| {
+//!         // This is running on a blocking thread.
+//!         // Blocking here is ok.
+//!     });
+//!
+//!     // We can wait for the blocking task like this:
+//!     // If the blocking task panics, the unwrap below will propagate the
+//!     // panic.
+//!     blocking_task.await.unwrap();
+//! }
+//! ```
+//!
+//! If your code is CPU-bound and you wish to limit the number of threads used
+//! to run it, you should use a separate thread pool dedicated to CPU bound tasks.
+//! For example, you could consider using the [rayon] library for CPU-bound
+//! tasks. It is also possible to create an extra Tokio runtime dedicated to
+//! CPU-bound tasks, but if you do this, you should be careful that the extra
+//! runtime runs _only_ CPU-bound tasks, as IO-bound tasks on that runtime
+//! will behave poorly.
+//!
+//! Hint: If using rayon, you can use a [`oneshot`] channel to send the result back
+//! to Tokio when the rayon task finishes.
+//!
+//! [rayon]: https://docs.rs/rayon
+//! [`oneshot`]: crate::sync::oneshot
+//!
+//! ## Asynchronous IO
+//!
+//! As well as scheduling and running tasks, Tokio provides everything you need
+//! to perform input and output asynchronously.
+//!
+//! The [`tokio::io`] module provides Tokio's asynchronous core I/O primitives,
+//! the [`AsyncRead`], [`AsyncWrite`], and [`AsyncBufRead`] traits. In addition,
+//! when the "io-util" feature flag is enabled, it also provides combinators and
+//! functions for working with these traits, forming as an asynchronous
+//! counterpart to [`std::io`].
+//!
+//! Tokio also includes APIs for performing various kinds of I/O and interacting
+//! with the operating system asynchronously. These include:
+//!
+//! * [`tokio::net`], which contains non-blocking versions of [TCP], [UDP], and
+//!   [Unix Domain Sockets][UDS] (enabled by the "net" feature flag),
+//! * [`tokio::fs`], similar to [`std::fs`] but for performing filesystem I/O
+//!   asynchronously (enabled by the "fs" feature flag),
+//! * [`tokio::signal`], for asynchronously handling Unix and Windows OS signals
+//!   (enabled by the "signal" feature flag),
+//! * [`tokio::process`], for spawning and managing child processes (enabled by
+//!   the "process" feature flag).
+//!
+//! [`tokio::io`]: crate::io
+//! [`AsyncRead`]: crate::io::AsyncRead
+//! [`AsyncWrite`]: crate::io::AsyncWrite
+//! [`AsyncBufRead`]: crate::io::AsyncBufRead
+//! [`std::io`]: std::io
+//! [`tokio::net`]: crate::net
+//! [TCP]: crate::net::tcp
+//! [UDP]: crate::net::UdpSocket
+//! [UDS]: crate::net::unix
+//! [`tokio::fs`]: crate::fs
+//! [`std::fs`]: std::fs
+//! [`tokio::signal`]: crate::signal
+//! [`tokio::process`]: crate::process
+//!
+//! # Examples
+//!
+//! A simple TCP echo server:
+//!
+//! ```no_run
+//! use tokio::net::TcpListener;
+//! use tokio::io::{AsyncReadExt, AsyncWriteExt};
+//!
+//! #[tokio::main]
+//! async fn main() -> Result<(), Box<dyn std::error::Error>> {
+//!     let listener = TcpListener::bind("127.0.0.1:8080").await?;
+//!
+//!     loop {
+//!         let (mut socket, _) = listener.accept().await?;
+//!
+//!         tokio::spawn(async move {
+//!             let mut buf = [0; 1024];
+//!
+//!             // In a loop, read data from the socket and write the data back.
+//!             loop {
+//!                 let n = match socket.read(&mut buf).await {
+//!                     // socket closed
+//!                     Ok(n) if n == 0 => return,
+//!                     Ok(n) => n,
+//!                     Err(e) => {
+//!                         eprintln!("failed to read from socket; err = {:?}", e);
+//!                         return;
+//!                     }
+//!                 };
+//!
+//!                 // Write the data back
+//!                 if let Err(e) = socket.write_all(&buf[0..n]).await {
+//!                     eprintln!("failed to write to socket; err = {:?}", e);
+//!                     return;
+//!                 }
+//!             }
+//!         });
+//!     }
+//! }
+//! ```
+//!
+//! ## Feature flags
+//!
+//! Tokio uses a set of [feature flags] to reduce the amount of compiled code. It
+//! is possible to just enable certain features over others. By default, Tokio
+//! does not enable any features but allows one to enable a subset for their use
+//! case. Below is a list of the available feature flags. You may also notice
+//! above each function, struct and trait there is listed one or more feature flags
+//! that are required for that item to be used. If you are new to Tokio it is
+//! recommended that you use the `full` feature flag which will enable all public APIs.
+//! Beware though that this will pull in many extra dependencies that you may not
+//! need.
+//!
+//! - `full`: Enables all features listed below except `test-util` and `tracing`.
+//! - `rt`: Enables `tokio::spawn`, the basic (current thread) scheduler,
+//!         and non-scheduler utilities.
+//! - `rt-multi-thread`: Enables the heavier, multi-threaded, work-stealing scheduler.
+//! - `io-util`: Enables the IO based `Ext` traits.
+//! - `io-std`: Enable `Stdout`, `Stdin` and `Stderr` types.
+//! - `net`: Enables `tokio::net` types such as `TcpStream`, `UnixStream` and
+//!          `UdpSocket`, as well as (on Unix-like systems) `AsyncFd` and (on
+//!          FreeBSD) `PollAio`.
+//! - `time`: Enables `tokio::time` types and allows the schedulers to enable
+//!           the built in timer.
+//! - `process`: Enables `tokio::process` types.
+//! - `macros`: Enables `#[tokio::main]` and `#[tokio::test]` macros.
+//! - `sync`: Enables all `tokio::sync` types.
+//! - `signal`: Enables all `tokio::signal` types.
+//! - `fs`: Enables `tokio::fs` types.
+//! - `test-util`: Enables testing based infrastructure for the Tokio runtime.
+//!
+//! _Note: `AsyncRead` and `AsyncWrite` traits do not require any features and are
+//! always available._
+//!
+//! ### Internal features
+//!
+//! These features do not expose any new API, but influence internal
+//! implementation aspects of Tokio, and can pull in additional
+//! dependencies.
+//!
+//! - `parking_lot`: As a potential optimization, use the _parking_lot_ crate's
+//! synchronization primitives internally. MSRV may increase according to the
+//! _parking_lot_ release in use.
+//!
+//! ### Unstable features
+//!
+//! These feature flags enable **unstable** features. The public API may break in 1.x
+//! releases. To enable these features, the `--cfg tokio_unstable` must be passed to
+//! `rustc` when compiling. This is easiest done using the `RUSTFLAGS` env variable:
+//! `RUSTFLAGS="--cfg tokio_unstable"`.
+//!
+//! - `tracing`: Enables tracing events.
+//!
+//! [feature flags]: https://doc.rust-lang.org/cargo/reference/manifest.html#the-features-section
+
+// Test that pointer width is compatible. This asserts that e.g. usize is at
+// least 32 bits, which a lot of components in Tokio currently assumes.
+//
+// TODO: improve once we have MSRV access to const eval to make more flexible.
+#[cfg(not(any(
+    target_pointer_width = "32",
+    target_pointer_width = "64",
+    target_pointer_width = "128"
+)))]
+compile_error! {
+    "Tokio requires the platform pointer width to be 32, 64, or 128 bits"
+}
+
+// Includes re-exports used by macros.
+//
+// This module is not intended to be part of the public API. In general, any
+// `doc(hidden)` code is not part of Tokio's public and stable API.
+#[macro_use]
+#[doc(hidden)]
+pub mod macros;
+
+cfg_fs! {
+    pub mod fs;
+}
+
+mod future;
+
+pub mod io;
+pub mod net;
+
+mod loom;
+mod park;
+
+cfg_process! {
+    pub mod process;
+}
+
+#[cfg(any(feature = "net", feature = "fs", feature = "io-std"))]
+mod blocking;
+
+cfg_rt! {
+    pub mod runtime;
+}
+
+pub(crate) mod coop;
+
+cfg_signal! {
+    pub mod signal;
+}
+
+cfg_signal_internal! {
+    #[cfg(not(feature = "signal"))]
+    #[allow(dead_code)]
+    #[allow(unreachable_pub)]
+    pub(crate) mod signal;
+}
+
+cfg_sync! {
+    pub mod sync;
+}
+cfg_not_sync! {
+    mod sync;
+}
+
+pub mod task;
+cfg_rt! {
+    pub use task::spawn;
+}
+
+cfg_time! {
+    pub mod time;
+}
+
+mod util;
+
+/// Due to the `Stream` trait's inclusion in `std` landing later than Tokio's 1.0
+/// release, most of the Tokio stream utilities have been moved into the [`tokio-stream`]
+/// crate.
+///
+/// # Why was `Stream` not included in Tokio 1.0?
+///
+/// Originally, we had planned to ship Tokio 1.0 with a stable `Stream` type
+/// but unfortunately the [RFC] had not been merged in time for `Stream` to
+/// reach `std` on a stable compiler in time for the 1.0 release of Tokio. For
+/// this reason, the team has decided to move all `Stream` based utilities to
+/// the [`tokio-stream`] crate. While this is not ideal, once `Stream` has made
+/// it into the standard library and the MSRV period has passed, we will implement
+/// stream for our different types.
+///
+/// While this may seem unfortunate, not all is lost as you can get much of the
+/// `Stream` support with `async/await` and `while let` loops. It is also possible
+/// to create a `impl Stream` from `async fn` using the [`async-stream`] crate.
+///
+/// [`tokio-stream`]: https://docs.rs/tokio-stream
+/// [`async-stream`]: https://docs.rs/async-stream
+/// [RFC]: https://github.com/rust-lang/rfcs/pull/2996
+///
+/// # Example
+///
+/// Convert a [`sync::mpsc::Receiver`] to an `impl Stream`.
+///
+/// ```rust,no_run
+/// use tokio::sync::mpsc;
+///
+/// let (tx, mut rx) = mpsc::channel::<usize>(16);
+///
+/// let stream = async_stream::stream! {
+///     while let Some(item) = rx.recv().await {
+///         yield item;
+///     }
+/// };
+/// ```
+pub mod stream {}
+
+// local re-exports of platform specific things, allowing for decent
+// documentation to be shimmed in on docs.rs
+
+#[cfg(docsrs)]
+pub mod doc;
+
+#[cfg(docsrs)]
+#[allow(unused)]
+pub(crate) use self::doc::os;
+
+#[cfg(not(docsrs))]
+#[allow(unused)]
+pub(crate) use std::os;
+
+#[cfg(docsrs)]
+#[allow(unused)]
+pub(crate) use self::doc::winapi;
+
+#[cfg(all(not(docsrs), windows, feature = "net"))]
+#[allow(unused)]
+pub(crate) use ::winapi;
+
+cfg_macros! {
+    /// Implementation detail of the `select!` macro. This macro is **not**
+    /// intended to be used as part of the public API and is permitted to
+    /// change.
+    #[doc(hidden)]
+    pub use tokio_macros::select_priv_declare_output_enum;
+
+    /// Implementation detail of the `select!` macro. This macro is **not**
+    /// intended to be used as part of the public API and is permitted to
+    /// change.
+    #[doc(hidden)]
+    pub use tokio_macros::select_priv_clean_pattern;
+
+    cfg_rt! {
+        #[cfg(feature = "rt-multi-thread")]
+        #[cfg(not(test))] // Work around for rust-lang/rust#62127
+        #[cfg_attr(docsrs, doc(cfg(feature = "macros")))]
+        #[doc(inline)]
+        pub use tokio_macros::main;
+
+        #[cfg(feature = "rt-multi-thread")]
+        #[cfg_attr(docsrs, doc(cfg(feature = "macros")))]
+        #[doc(inline)]
+        pub use tokio_macros::test;
+
+        cfg_not_rt_multi_thread! {
+            #[cfg(not(test))] // Work around for rust-lang/rust#62127
+            #[doc(inline)]
+            pub use tokio_macros::main_rt as main;
+
+            #[doc(inline)]
+            pub use tokio_macros::test_rt as test;
+        }
+    }
+
+    // Always fail if rt is not enabled.
+    cfg_not_rt! {
+        #[cfg(not(test))]
+        #[doc(inline)]
+        pub use tokio_macros::main_fail as main;
+
+        #[doc(inline)]
+        pub use tokio_macros::test_fail as test;
+    }
+}
+
+// TODO: rm
+#[cfg(feature = "io-util")]
+#[cfg(test)]
+fn is_unpin<T: Unpin>() {}