forked from mirror/async-std
Revert "Stabilize most stream method and remove unnecessary macros"
nasa
5 years ago
committed by
GitHub
parent
61f9483cc5
commit
cc19592f80
@ -0,0 +1,261 @@
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use std::pin::Pin;
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use std::sync::Mutex;
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use std::future::Future;
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use crate::io::{self, Write};
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use crate::task::{spawn_blocking, Context, JoinHandle, Poll};
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cfg_unstable! {
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use once_cell::sync::Lazy;
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use std::io::Write as _;
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}
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/// Constructs a new handle to the standard error of the current process.
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///
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/// This function is an async version of [`std::io::stderr`].
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///
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/// [`std::io::stderr`]: https://doc.rust-lang.org/std/io/fn.stderr.html
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///
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/// ### Note: Windows Portability Consideration
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///
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/// When operating in a console, the Windows implementation of this stream does not support
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/// non-UTF-8 byte sequences. Attempting to write bytes that are not valid UTF-8 will return
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/// an error.
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///
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/// # Examples
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///
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/// ```no_run
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/// # fn main() -> std::io::Result<()> { async_std::task::block_on(async {
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/// #
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/// use async_std::io;
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/// use async_std::prelude::*;
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///
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/// let mut stderr = io::stderr();
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/// stderr.write_all(b"Hello, world!").await?;
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/// #
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/// # Ok(()) }) }
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/// ```
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pub fn stderr() -> Stderr {
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Stderr(Mutex::new(State::Idle(Some(Inner {
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stderr: std::io::stderr(),
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buf: Vec::new(),
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last_op: None,
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}))))
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}
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/// A handle to the standard error of the current process.
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///
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/// This writer is created by the [`stderr`] function. See its documentation for
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/// more.
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///
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/// ### Note: Windows Portability Consideration
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///
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/// When operating in a console, the Windows implementation of this stream does not support
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/// non-UTF-8 byte sequences. Attempting to write bytes that are not valid UTF-8 will return
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/// an error.
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///
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/// [`stderr`]: fn.stderr.html
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#[derive(Debug)]
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pub struct Stderr(Mutex<State>);
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/// A locked reference to the Stderr handle.
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///
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/// This handle implements the [`Write`] traits, and is constructed via the [`Stderr::lock`]
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/// method.
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///
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/// [`Write`]: trait.Read.html
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/// [`Stderr::lock`]: struct.Stderr.html#method.lock
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#[cfg(feature = "unstable")]
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#[cfg_attr(feature = "docs", doc(cfg(unstable)))]
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#[derive(Debug)]
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pub struct StderrLock<'a>(std::io::StderrLock<'a>);
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#[cfg(feature = "unstable")]
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#[cfg_attr(feature = "docs", doc(cfg(unstable)))]
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unsafe impl Send for StderrLock<'_> {}
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/// The state of the asynchronous stderr.
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///
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/// The stderr can be either idle or busy performing an asynchronous operation.
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#[derive(Debug)]
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enum State {
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/// The stderr is idle.
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Idle(Option<Inner>),
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/// The stderr is blocked on an asynchronous operation.
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///
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/// Awaiting this operation will result in the new state of the stderr.
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Busy(JoinHandle<State>),
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}
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/// Inner representation of the asynchronous stderr.
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#[derive(Debug)]
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struct Inner {
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/// The blocking stderr handle.
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stderr: std::io::Stderr,
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/// The write buffer.
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buf: Vec<u8>,
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/// The result of the last asynchronous operation on the stderr.
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last_op: Option<Operation>,
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}
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/// Possible results of an asynchronous operation on the stderr.
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#[derive(Debug)]
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enum Operation {
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Write(io::Result<usize>),
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Flush(io::Result<()>),
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}
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impl Stderr {
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/// Locks this handle to the standard error stream, returning a writable guard.
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///
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/// The lock is released when the returned lock goes out of scope. The returned guard also implements the Write trait for writing data.
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///
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/// # Examples
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///
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/// ```no_run
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/// # fn main() -> std::io::Result<()> { async_std::task::block_on(async {
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/// #
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/// use async_std::io;
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/// use async_std::prelude::*;
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///
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/// let stderr = io::stderr();
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/// let mut handle = stderr.lock().await;
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///
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/// handle.write_all(b"hello world").await?;
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/// #
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/// # Ok(()) }) }
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/// ```
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#[cfg_attr(feature = "docs", doc(cfg(unstable)))]
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#[cfg(any(feature = "unstable", feature = "docs"))]
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pub async fn lock(&self) -> StderrLock<'static> {
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static STDERR: Lazy<std::io::Stderr> = Lazy::new(std::io::stderr);
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spawn_blocking(move || StderrLock(STDERR.lock())).await
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}
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}
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impl Write for Stderr {
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fn poll_write(
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mut self: Pin<&mut Self>,
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cx: &mut Context<'_>,
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buf: &[u8],
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) -> Poll<io::Result<usize>> {
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let state = &mut *self.0.lock().unwrap();
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loop {
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match state {
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State::Idle(opt) => {
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let inner = opt.as_mut().unwrap();
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// Check if the operation has completed.
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if let Some(Operation::Write(res)) = inner.last_op.take() {
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let n = res?;
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// If more data was written than is available in the buffer, let's retry
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// the write operation.
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if n <= buf.len() {
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return Poll::Ready(Ok(n));
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}
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} else {
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let mut inner = opt.take().unwrap();
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// Set the length of the inner buffer to the length of the provided buffer.
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if inner.buf.len() < buf.len() {
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inner.buf.reserve(buf.len() - inner.buf.len());
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}
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unsafe {
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inner.buf.set_len(buf.len());
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}
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// Copy the data to write into the inner buffer.
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inner.buf[..buf.len()].copy_from_slice(buf);
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// Start the operation asynchronously.
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*state = State::Busy(spawn_blocking(move || {
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let res = std::io::Write::write(&mut inner.stderr, &inner.buf);
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inner.last_op = Some(Operation::Write(res));
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State::Idle(Some(inner))
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}));
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}
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}
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// Poll the asynchronous operation the stderr is currently blocked on.
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State::Busy(task) => *state = futures_core::ready!(Pin::new(task).poll(cx)),
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}
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}
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}
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fn poll_flush(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<()>> {
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let state = &mut *self.0.lock().unwrap();
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loop {
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match state {
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State::Idle(opt) => {
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let inner = opt.as_mut().unwrap();
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// Check if the operation has completed.
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if let Some(Operation::Flush(res)) = inner.last_op.take() {
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return Poll::Ready(res);
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} else {
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let mut inner = opt.take().unwrap();
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// Start the operation asynchronously.
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*state = State::Busy(spawn_blocking(move || {
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let res = std::io::Write::flush(&mut inner.stderr);
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inner.last_op = Some(Operation::Flush(res));
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State::Idle(Some(inner))
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}));
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}
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}
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// Poll the asynchronous operation the stderr is currently blocked on.
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State::Busy(task) => *state = futures_core::ready!(Pin::new(task).poll(cx)),
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}
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}
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}
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fn poll_close(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<()>> {
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self.poll_flush(cx)
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}
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}
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cfg_unix! {
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use crate::os::unix::io::{AsRawFd, RawFd};
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impl AsRawFd for Stderr {
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fn as_raw_fd(&self) -> RawFd {
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std::io::stderr().as_raw_fd()
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}
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}
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}
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cfg_windows! {
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use crate::os::windows::io::{AsRawHandle, RawHandle};
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impl AsRawHandle for Stderr {
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fn as_raw_handle(&self) -> RawHandle {
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std::io::stderr().as_raw_handle()
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}
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}
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}
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#[cfg(feature = "unstable")]
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#[cfg_attr(feature = "docs", doc(cfg(unstable)))]
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impl io::Write for StderrLock<'_> {
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fn poll_write(
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mut self: Pin<&mut Self>,
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_cx: &mut Context<'_>,
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buf: &[u8],
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) -> Poll<io::Result<usize>> {
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Poll::Ready(self.0.write(buf))
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}
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fn poll_flush(mut self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<io::Result<()>> {
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Poll::Ready(self.0.flush())
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}
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fn poll_close(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<()>> {
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self.poll_flush(cx)
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}
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}
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@ -0,0 +1,279 @@
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use std::future::Future;
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use std::pin::Pin;
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use std::sync::Mutex;
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use crate::future;
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use crate::io::{self, Read};
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use crate::task::{spawn_blocking, Context, JoinHandle, Poll};
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use crate::utils::Context as _;
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cfg_unstable! {
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use once_cell::sync::Lazy;
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use std::io::Read as _;
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}
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/// Constructs a new handle to the standard input of the current process.
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///
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/// This function is an async version of [`std::io::stdin`].
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///
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/// [`std::io::stdin`]: https://doc.rust-lang.org/std/io/fn.stdin.html
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///
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/// ### Note: Windows Portability Consideration
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///
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/// When operating in a console, the Windows implementation of this stream does not support
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/// non-UTF-8 byte sequences. Attempting to write bytes that are not valid UTF-8 will return
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/// an error.
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///
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/// # Examples
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///
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/// ```no_run
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/// # fn main() -> std::io::Result<()> { async_std::task::block_on(async {
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/// #
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/// use async_std::io;
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///
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/// let stdin = io::stdin();
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/// let mut line = String::new();
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/// stdin.read_line(&mut line).await?;
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/// #
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/// # Ok(()) }) }
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/// ```
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pub fn stdin() -> Stdin {
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Stdin(Mutex::new(State::Idle(Some(Inner {
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stdin: std::io::stdin(),
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line: String::new(),
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buf: Vec::new(),
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last_op: None,
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}))))
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}
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/// A handle to the standard input of the current process.
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///
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/// This reader is created by the [`stdin`] function. See its documentation for
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/// more.
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///
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/// ### Note: Windows Portability Consideration
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///
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/// When operating in a console, the Windows implementation of this stream does not support
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/// non-UTF-8 byte sequences. Attempting to write bytes that are not valid UTF-8 will return
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/// an error.
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///
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/// [`stdin`]: fn.stdin.html
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#[derive(Debug)]
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pub struct Stdin(Mutex<State>);
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/// A locked reference to the Stdin handle.
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///
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/// This handle implements the [`Read`] traits, and is constructed via the [`Stdin::lock`] method.
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///
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/// [`Read`]: trait.Read.html
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/// [`Stdin::lock`]: struct.Stdin.html#method.lock
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#[cfg_attr(feature = "docs", doc(cfg(unstable)))]
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#[cfg(feature = "unstable")]
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#[derive(Debug)]
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pub struct StdinLock<'a>(std::io::StdinLock<'a>);
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#[cfg(feature = "unstable")]
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#[cfg_attr(feature = "docs", doc(cfg(unstable)))]
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unsafe impl Send for StdinLock<'_> {}
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/// The state of the asynchronous stdin.
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///
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/// The stdin can be either idle or busy performing an asynchronous operation.
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#[derive(Debug)]
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enum State {
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/// The stdin is idle.
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Idle(Option<Inner>),
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/// The stdin is blocked on an asynchronous operation.
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///
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/// Awaiting this operation will result in the new state of the stdin.
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Busy(JoinHandle<State>),
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}
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/// Inner representation of the asynchronous stdin.
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#[derive(Debug)]
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struct Inner {
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/// The blocking stdin handle.
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stdin: std::io::Stdin,
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/// The line buffer.
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line: String,
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/// The write buffer.
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buf: Vec<u8>,
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/// The result of the last asynchronous operation on the stdin.
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last_op: Option<Operation>,
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}
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/// Possible results of an asynchronous operation on the stdin.
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#[derive(Debug)]
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enum Operation {
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ReadLine(io::Result<usize>),
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Read(io::Result<usize>),
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}
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impl Stdin {
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/// Reads a line of input into the specified buffer.
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///
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/// # Examples
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///
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/// ```no_run
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/// # fn main() -> std::io::Result<()> { async_std::task::block_on(async {
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/// #
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/// use async_std::io;
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///
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/// let stdin = io::stdin();
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/// let mut line = String::new();
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/// stdin.read_line(&mut line).await?;
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/// #
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/// # Ok(()) }) }
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/// ```
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pub async fn read_line(&self, buf: &mut String) -> io::Result<usize> {
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future::poll_fn(|cx| {
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let state = &mut *self.0.lock().unwrap();
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loop {
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match state {
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State::Idle(opt) => {
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let inner = opt.as_mut().unwrap();
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// Check if the operation has completed.
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if let Some(Operation::ReadLine(res)) = inner.last_op.take() {
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let n = res?;
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// Copy the read data into the buffer and return.
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buf.push_str(&inner.line);
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return Poll::Ready(Ok(n));
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} else {
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let mut inner = opt.take().unwrap();
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// Start the operation asynchronously.
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*state = State::Busy(spawn_blocking(move || {
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inner.line.clear();
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let res = inner.stdin.read_line(&mut inner.line);
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inner.last_op = Some(Operation::ReadLine(res));
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State::Idle(Some(inner))
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}));
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}
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}
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// Poll the asynchronous operation the stdin is currently blocked on.
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State::Busy(task) => *state = futures_core::ready!(Pin::new(task).poll(cx)),
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}
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}
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})
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.await
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.context(|| String::from("could not read line on stdin"))
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}
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/// Locks this handle to the standard input stream, returning a readable guard.
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///
|
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/// The lock is released when the returned lock goes out of scope. The returned guard also implements the Read trait for accessing the underlying data.
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///
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/// # Examples
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///
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/// ```no_run
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/// # fn main() -> std::io::Result<()> { async_std::task::block_on(async {
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/// #
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/// use async_std::io;
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/// use async_std::prelude::*;
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///
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/// let mut buffer = String::new();
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///
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/// let stdin = io::stdin();
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/// let mut handle = stdin.lock().await;
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///
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/// handle.read_to_string(&mut buffer).await?;
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/// #
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/// # Ok(()) }) }
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/// ```
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#[cfg_attr(feature = "docs", doc(cfg(unstable)))]
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#[cfg(any(feature = "unstable", feature = "docs"))]
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pub async fn lock(&self) -> StdinLock<'static> {
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static STDIN: Lazy<std::io::Stdin> = Lazy::new(std::io::stdin);
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spawn_blocking(move || StdinLock(STDIN.lock())).await
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}
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}
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impl Read for Stdin {
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fn poll_read(
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mut self: Pin<&mut Self>,
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cx: &mut Context<'_>,
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buf: &mut [u8],
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) -> Poll<io::Result<usize>> {
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let state = &mut *self.0.lock().unwrap();
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|
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loop {
|
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match state {
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State::Idle(opt) => {
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let inner = opt.as_mut().unwrap();
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|
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// Check if the operation has completed.
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if let Some(Operation::Read(res)) = inner.last_op.take() {
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let n = res?;
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// If more data was read than fits into the buffer, let's retry the read
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// operation.
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if n <= buf.len() {
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// Copy the read data into the buffer and return.
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buf[..n].copy_from_slice(&inner.buf[..n]);
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return Poll::Ready(Ok(n));
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}
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} else {
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let mut inner = opt.take().unwrap();
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// Set the length of the inner buffer to the length of the provided buffer.
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if inner.buf.len() < buf.len() {
|
||||
inner.buf.reserve(buf.len() - inner.buf.len());
|
||||
}
|
||||
unsafe {
|
||||
inner.buf.set_len(buf.len());
|
||||
}
|
||||
|
||||
// Start the operation asynchronously.
|
||||
*state = State::Busy(spawn_blocking(move || {
|
||||
let res = std::io::Read::read(&mut inner.stdin, &mut inner.buf);
|
||||
inner.last_op = Some(Operation::Read(res));
|
||||
State::Idle(Some(inner))
|
||||
}));
|
||||
}
|
||||
}
|
||||
// Poll the asynchronous operation the stdin is currently blocked on.
|
||||
State::Busy(task) => *state = futures_core::ready!(Pin::new(task).poll(cx)),
|
||||
}
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
cfg_unix! {
|
||||
use crate::os::unix::io::{AsRawFd, RawFd};
|
||||
|
||||
impl AsRawFd for Stdin {
|
||||
fn as_raw_fd(&self) -> RawFd {
|
||||
std::io::stdin().as_raw_fd()
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
cfg_windows! {
|
||||
use crate::os::windows::io::{AsRawHandle, RawHandle};
|
||||
|
||||
impl AsRawHandle for Stdin {
|
||||
fn as_raw_handle(&self) -> RawHandle {
|
||||
std::io::stdin().as_raw_handle()
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
#[cfg(feature = "unstable")]
|
||||
#[cfg_attr(feature = "docs", doc(cfg(unstable)))]
|
||||
impl Read for StdinLock<'_> {
|
||||
fn poll_read(
|
||||
mut self: Pin<&mut Self>,
|
||||
_cx: &mut Context<'_>,
|
||||
buf: &mut [u8],
|
||||
) -> Poll<io::Result<usize>> {
|
||||
Poll::Ready(self.0.read(buf))
|
||||
}
|
||||
}
|
||||
@ -0,0 +1,21 @@
|
||||
//! Internal types for stdio.
|
||||
//!
|
||||
//! This module is a port of `libstd/io/stdio.rs`,and contains internal types for `print`/`eprint`.
|
||||
|
||||
use crate::io::{stderr, stdout};
|
||||
use crate::prelude::*;
|
||||
use std::fmt;
|
||||
|
||||
#[doc(hidden)]
|
||||
pub async fn _print(args: fmt::Arguments<'_>) {
|
||||
if let Err(e) = stdout().write_fmt(args).await {
|
||||
panic!("failed printing to stdout: {}", e);
|
||||
}
|
||||
}
|
||||
|
||||
#[doc(hidden)]
|
||||
pub async fn _eprint(args: fmt::Arguments<'_>) {
|
||||
if let Err(e) = stderr().write_fmt(args).await {
|
||||
panic!("failed printing to stderr: {}", e);
|
||||
}
|
||||
}
|
||||
@ -0,0 +1,261 @@
|
||||
use std::pin::Pin;
|
||||
use std::sync::Mutex;
|
||||
use std::future::Future;
|
||||
|
||||
use crate::io::{self, Write};
|
||||
use crate::task::{spawn_blocking, Context, JoinHandle, Poll};
|
||||
|
||||
cfg_unstable! {
|
||||
use once_cell::sync::Lazy;
|
||||
use std::io::Write as _;
|
||||
}
|
||||
|
||||
/// Constructs a new handle to the standard output of the current process.
|
||||
///
|
||||
/// This function is an async version of [`std::io::stdout`].
|
||||
///
|
||||
/// [`std::io::stdout`]: https://doc.rust-lang.org/std/io/fn.stdout.html
|
||||
///
|
||||
/// ### Note: Windows Portability Consideration
|
||||
///
|
||||
/// When operating in a console, the Windows implementation of this stream does not support
|
||||
/// non-UTF-8 byte sequences. Attempting to write bytes that are not valid UTF-8 will return
|
||||
/// an error.
|
||||
///
|
||||
/// # Examples
|
||||
///
|
||||
/// ```no_run
|
||||
/// # fn main() -> std::io::Result<()> { async_std::task::block_on(async {
|
||||
/// #
|
||||
/// use async_std::io;
|
||||
/// use async_std::prelude::*;
|
||||
///
|
||||
/// let mut stdout = io::stdout();
|
||||
/// stdout.write_all(b"Hello, world!").await?;
|
||||
/// #
|
||||
/// # Ok(()) }) }
|
||||
/// ```
|
||||
pub fn stdout() -> Stdout {
|
||||
Stdout(Mutex::new(State::Idle(Some(Inner {
|
||||
stdout: std::io::stdout(),
|
||||
buf: Vec::new(),
|
||||
last_op: None,
|
||||
}))))
|
||||
}
|
||||
|
||||
/// A handle to the standard output of the current process.
|
||||
///
|
||||
/// This writer is created by the [`stdout`] function. See its documentation
|
||||
/// for more.
|
||||
///
|
||||
/// ### Note: Windows Portability Consideration
|
||||
///
|
||||
/// When operating in a console, the Windows implementation of this stream does not support
|
||||
/// non-UTF-8 byte sequences. Attempting to write bytes that are not valid UTF-8 will return
|
||||
/// an error.
|
||||
///
|
||||
/// [`stdout`]: fn.stdout.html
|
||||
#[derive(Debug)]
|
||||
pub struct Stdout(Mutex<State>);
|
||||
|
||||
/// A locked reference to the Stderr handle.
|
||||
///
|
||||
/// This handle implements the [`Write`] traits, and is constructed via the [`Stdout::lock`]
|
||||
/// method.
|
||||
///
|
||||
/// [`Write`]: trait.Read.html
|
||||
/// [`Stdout::lock`]: struct.Stdout.html#method.lock
|
||||
#[cfg(feature = "unstable")]
|
||||
#[cfg_attr(feature = "docs", doc(cfg(unstable)))]
|
||||
#[derive(Debug)]
|
||||
pub struct StdoutLock<'a>(std::io::StdoutLock<'a>);
|
||||
|
||||
#[cfg(feature = "unstable")]
|
||||
#[cfg_attr(feature = "docs", doc(cfg(unstable)))]
|
||||
unsafe impl Send for StdoutLock<'_> {}
|
||||
|
||||
/// The state of the asynchronous stdout.
|
||||
///
|
||||
/// The stdout can be either idle or busy performing an asynchronous operation.
|
||||
#[derive(Debug)]
|
||||
enum State {
|
||||
/// The stdout is idle.
|
||||
Idle(Option<Inner>),
|
||||
|
||||
/// The stdout is blocked on an asynchronous operation.
|
||||
///
|
||||
/// Awaiting this operation will result in the new state of the stdout.
|
||||
Busy(JoinHandle<State>),
|
||||
}
|
||||
|
||||
/// Inner representation of the asynchronous stdout.
|
||||
#[derive(Debug)]
|
||||
struct Inner {
|
||||
/// The blocking stdout handle.
|
||||
stdout: std::io::Stdout,
|
||||
|
||||
/// The write buffer.
|
||||
buf: Vec<u8>,
|
||||
|
||||
/// The result of the last asynchronous operation on the stdout.
|
||||
last_op: Option<Operation>,
|
||||
}
|
||||
|
||||
/// Possible results of an asynchronous operation on the stdout.
|
||||
#[derive(Debug)]
|
||||
enum Operation {
|
||||
Write(io::Result<usize>),
|
||||
Flush(io::Result<()>),
|
||||
}
|
||||
|
||||
impl Stdout {
|
||||
/// Locks this handle to the standard error stream, returning a writable guard.
|
||||
///
|
||||
/// The lock is released when the returned lock goes out of scope. The returned guard also implements the Write trait for writing data.
|
||||
///
|
||||
/// # Examples
|
||||
///
|
||||
/// ```no_run
|
||||
/// # fn main() -> std::io::Result<()> { async_std::task::block_on(async {
|
||||
/// #
|
||||
/// use async_std::io;
|
||||
/// use async_std::prelude::*;
|
||||
///
|
||||
/// let stdout = io::stdout();
|
||||
/// let mut handle = stdout.lock().await;
|
||||
///
|
||||
/// handle.write_all(b"hello world").await?;
|
||||
/// #
|
||||
/// # Ok(()) }) }
|
||||
/// ```
|
||||
#[cfg_attr(feature = "docs", doc(cfg(unstable)))]
|
||||
#[cfg(any(feature = "unstable", feature = "docs"))]
|
||||
pub async fn lock(&self) -> StdoutLock<'static> {
|
||||
static STDOUT: Lazy<std::io::Stdout> = Lazy::new(std::io::stdout);
|
||||
|
||||
spawn_blocking(move || StdoutLock(STDOUT.lock())).await
|
||||
}
|
||||
}
|
||||
|
||||
impl Write for Stdout {
|
||||
fn poll_write(
|
||||
mut self: Pin<&mut Self>,
|
||||
cx: &mut Context<'_>,
|
||||
buf: &[u8],
|
||||
) -> Poll<io::Result<usize>> {
|
||||
let state = &mut *self.0.lock().unwrap();
|
||||
|
||||
loop {
|
||||
match state {
|
||||
State::Idle(opt) => {
|
||||
let inner = opt.as_mut().unwrap();
|
||||
|
||||
// Check if the operation has completed.
|
||||
if let Some(Operation::Write(res)) = inner.last_op.take() {
|
||||
let n = res?;
|
||||
|
||||
// If more data was written than is available in the buffer, let's retry
|
||||
// the write operation.
|
||||
if n <= buf.len() {
|
||||
return Poll::Ready(Ok(n));
|
||||
}
|
||||
} else {
|
||||
let mut inner = opt.take().unwrap();
|
||||
|
||||
// Set the length of the inner buffer to the length of the provided buffer.
|
||||
if inner.buf.len() < buf.len() {
|
||||
inner.buf.reserve(buf.len() - inner.buf.len());
|
||||
}
|
||||
unsafe {
|
||||
inner.buf.set_len(buf.len());
|
||||
}
|
||||
|
||||
// Copy the data to write into the inner buffer.
|
||||
inner.buf[..buf.len()].copy_from_slice(buf);
|
||||
|
||||
// Start the operation asynchronously.
|
||||
*state = State::Busy(spawn_blocking(move || {
|
||||
let res = std::io::Write::write(&mut inner.stdout, &inner.buf);
|
||||
inner.last_op = Some(Operation::Write(res));
|
||||
State::Idle(Some(inner))
|
||||
}));
|
||||
}
|
||||
}
|
||||
// Poll the asynchronous operation the stdout is currently blocked on.
|
||||
State::Busy(task) => *state = futures_core::ready!(Pin::new(task).poll(cx)),
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
fn poll_flush(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<()>> {
|
||||
let state = &mut *self.0.lock().unwrap();
|
||||
|
||||
loop {
|
||||
match state {
|
||||
State::Idle(opt) => {
|
||||
let inner = opt.as_mut().unwrap();
|
||||
|
||||
// Check if the operation has completed.
|
||||
if let Some(Operation::Flush(res)) = inner.last_op.take() {
|
||||
return Poll::Ready(res);
|
||||
} else {
|
||||
let mut inner = opt.take().unwrap();
|
||||
|
||||
// Start the operation asynchronously.
|
||||
*state = State::Busy(spawn_blocking(move || {
|
||||
let res = std::io::Write::flush(&mut inner.stdout);
|
||||
inner.last_op = Some(Operation::Flush(res));
|
||||
State::Idle(Some(inner))
|
||||
}));
|
||||
}
|
||||
}
|
||||
// Poll the asynchronous operation the stdout is currently blocked on.
|
||||
State::Busy(task) => *state = futures_core::ready!(Pin::new(task).poll(cx)),
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
fn poll_close(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<()>> {
|
||||
self.poll_flush(cx)
|
||||
}
|
||||
}
|
||||
|
||||
cfg_unix! {
|
||||
use crate::os::unix::io::{AsRawFd, RawFd};
|
||||
|
||||
impl AsRawFd for Stdout {
|
||||
fn as_raw_fd(&self) -> RawFd {
|
||||
std::io::stdout().as_raw_fd()
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
cfg_windows! {
|
||||
use crate::os::windows::io::{AsRawHandle, RawHandle};
|
||||
|
||||
impl AsRawHandle for Stdout {
|
||||
fn as_raw_handle(&self) -> RawHandle {
|
||||
std::io::stdout().as_raw_handle()
|
||||
}
|
||||
}
|
||||
}
|
||||
|
||||
#[cfg(feature = "unstable")]
|
||||
#[cfg_attr(feature = "docs", doc(cfg(unstable)))]
|
||||
impl Write for StdoutLock<'_> {
|
||||
fn poll_write(
|
||||
mut self: Pin<&mut Self>,
|
||||
_cx: &mut Context<'_>,
|
||||
buf: &[u8],
|
||||
) -> Poll<io::Result<usize>> {
|
||||
Poll::Ready(self.0.write(buf))
|
||||
}
|
||||
|
||||
fn poll_flush(mut self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<io::Result<()>> {
|
||||
Poll::Ready(self.0.flush())
|
||||
}
|
||||
|
||||
fn poll_close(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<()>> {
|
||||
self.poll_flush(cx)
|
||||
}
|
||||
}
|
||||
Loading…
Reference in New Issue