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Diffstat (limited to 'third_party/rust/tokio/src/io/util')
37 files changed, 6891 insertions, 0 deletions
diff --git a/third_party/rust/tokio/src/io/util/async_buf_read_ext.rs b/third_party/rust/tokio/src/io/util/async_buf_read_ext.rs new file mode 100644 index 0000000000..b241e354ba --- /dev/null +++ b/third_party/rust/tokio/src/io/util/async_buf_read_ext.rs @@ -0,0 +1,351 @@ +use crate::io::util::fill_buf::{fill_buf, FillBuf}; +use crate::io::util::lines::{lines, Lines}; +use crate::io::util::read_line::{read_line, ReadLine}; +use crate::io::util::read_until::{read_until, ReadUntil}; +use crate::io::util::split::{split, Split}; +use crate::io::AsyncBufRead; + +cfg_io_util! { + /// An extension trait which adds utility methods to [`AsyncBufRead`] types. + /// + /// [`AsyncBufRead`]: crate::io::AsyncBufRead + pub trait AsyncBufReadExt: AsyncBufRead { + /// Reads all bytes into `buf` until the delimiter `byte` or EOF is reached. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn read_until(&mut self, byte: u8, buf: &mut Vec<u8>) -> io::Result<usize>; + /// ``` + /// + /// This function will read bytes from the underlying stream until the + /// delimiter or EOF is found. Once found, all bytes up to, and including, + /// the delimiter (if found) will be appended to `buf`. + /// + /// If successful, this function will return the total number of bytes read. + /// + /// If this function returns `Ok(0)`, the stream has reached EOF. + /// + /// # Errors + /// + /// This function will ignore all instances of [`ErrorKind::Interrupted`] and + /// will otherwise return any errors returned by [`fill_buf`]. + /// + /// If an I/O error is encountered then all bytes read so far will be + /// present in `buf` and its length will have been adjusted appropriately. + /// + /// [`fill_buf`]: AsyncBufRead::poll_fill_buf + /// [`ErrorKind::Interrupted`]: std::io::ErrorKind::Interrupted + /// + /// # Cancel safety + /// + /// If the method is used as the event in a + /// [`tokio::select!`](crate::select) statement and some other branch + /// completes first, then some data may have been partially read. Any + /// partially read bytes are appended to `buf`, and the method can be + /// called again to continue reading until `byte`. + /// + /// This method returns the total number of bytes read. If you cancel + /// the call to `read_until` and then call it again to continue reading, + /// the counter is reset. + /// + /// # Examples + /// + /// [`std::io::Cursor`][`Cursor`] is a type that implements `BufRead`. In + /// this example, we use [`Cursor`] to read all the bytes in a byte slice + /// in hyphen delimited segments: + /// + /// [`Cursor`]: std::io::Cursor + /// + /// ``` + /// use tokio::io::AsyncBufReadExt; + /// + /// use std::io::Cursor; + /// + /// #[tokio::main] + /// async fn main() { + /// let mut cursor = Cursor::new(b"lorem-ipsum"); + /// let mut buf = vec![]; + /// + /// // cursor is at 'l' + /// let num_bytes = cursor.read_until(b'-', &mut buf) + /// .await + /// .expect("reading from cursor won't fail"); + /// + /// assert_eq!(num_bytes, 6); + /// assert_eq!(buf, b"lorem-"); + /// buf.clear(); + /// + /// // cursor is at 'i' + /// let num_bytes = cursor.read_until(b'-', &mut buf) + /// .await + /// .expect("reading from cursor won't fail"); + /// + /// assert_eq!(num_bytes, 5); + /// assert_eq!(buf, b"ipsum"); + /// buf.clear(); + /// + /// // cursor is at EOF + /// let num_bytes = cursor.read_until(b'-', &mut buf) + /// .await + /// .expect("reading from cursor won't fail"); + /// assert_eq!(num_bytes, 0); + /// assert_eq!(buf, b""); + /// } + /// ``` + fn read_until<'a>(&'a mut self, byte: u8, buf: &'a mut Vec<u8>) -> ReadUntil<'a, Self> + where + Self: Unpin, + { + read_until(self, byte, buf) + } + + /// Reads all bytes until a newline (the 0xA byte) is reached, and append + /// them to the provided buffer. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn read_line(&mut self, buf: &mut String) -> io::Result<usize>; + /// ``` + /// + /// This function will read bytes from the underlying stream until the + /// newline delimiter (the 0xA byte) or EOF is found. Once found, all bytes + /// up to, and including, the delimiter (if found) will be appended to + /// `buf`. + /// + /// If successful, this function will return the total number of bytes read. + /// + /// If this function returns `Ok(0)`, the stream has reached EOF. + /// + /// # Errors + /// + /// This function has the same error semantics as [`read_until`] and will + /// also return an error if the read bytes are not valid UTF-8. If an I/O + /// error is encountered then `buf` may contain some bytes already read in + /// the event that all data read so far was valid UTF-8. + /// + /// [`read_until`]: AsyncBufReadExt::read_until + /// + /// # Cancel safety + /// + /// This method is not cancellation safe. If the method is used as the + /// event in a [`tokio::select!`](crate::select) statement and some + /// other branch completes first, then some data may have been partially + /// read, and this data is lost. There are no guarantees regarding the + /// contents of `buf` when the call is cancelled. The current + /// implementation replaces `buf` with the empty string, but this may + /// change in the future. + /// + /// This function does not behave like [`read_until`] because of the + /// requirement that a string contains only valid utf-8. If you need a + /// cancellation safe `read_line`, there are three options: + /// + /// * Call [`read_until`] with a newline character and manually perform the utf-8 check. + /// * The stream returned by [`lines`] has a cancellation safe + /// [`next_line`] method. + /// * Use [`tokio_util::codec::LinesCodec`][LinesCodec]. + /// + /// [LinesCodec]: https://docs.rs/tokio-util/0.6/tokio_util/codec/struct.LinesCodec.html + /// [`read_until`]: Self::read_until + /// [`lines`]: Self::lines + /// [`next_line`]: crate::io::Lines::next_line + /// + /// # Examples + /// + /// [`std::io::Cursor`][`Cursor`] is a type that implements + /// `AsyncBufRead`. In this example, we use [`Cursor`] to read all the + /// lines in a byte slice: + /// + /// [`Cursor`]: std::io::Cursor + /// + /// ``` + /// use tokio::io::AsyncBufReadExt; + /// + /// use std::io::Cursor; + /// + /// #[tokio::main] + /// async fn main() { + /// let mut cursor = Cursor::new(b"foo\nbar"); + /// let mut buf = String::new(); + /// + /// // cursor is at 'f' + /// let num_bytes = cursor.read_line(&mut buf) + /// .await + /// .expect("reading from cursor won't fail"); + /// + /// assert_eq!(num_bytes, 4); + /// assert_eq!(buf, "foo\n"); + /// buf.clear(); + /// + /// // cursor is at 'b' + /// let num_bytes = cursor.read_line(&mut buf) + /// .await + /// .expect("reading from cursor won't fail"); + /// + /// assert_eq!(num_bytes, 3); + /// assert_eq!(buf, "bar"); + /// buf.clear(); + /// + /// // cursor is at EOF + /// let num_bytes = cursor.read_line(&mut buf) + /// .await + /// .expect("reading from cursor won't fail"); + /// + /// assert_eq!(num_bytes, 0); + /// assert_eq!(buf, ""); + /// } + /// ``` + fn read_line<'a>(&'a mut self, buf: &'a mut String) -> ReadLine<'a, Self> + where + Self: Unpin, + { + read_line(self, buf) + } + + /// Returns a stream of the contents of this reader split on the byte + /// `byte`. + /// + /// This method is the asynchronous equivalent to + /// [`BufRead::split`](std::io::BufRead::split). + /// + /// The stream returned from this function will yield instances of + /// [`io::Result`]`<`[`Option`]`<`[`Vec<u8>`]`>>`. Each vector returned will *not* have + /// the delimiter byte at the end. + /// + /// [`io::Result`]: std::io::Result + /// [`Option`]: core::option::Option + /// [`Vec<u8>`]: std::vec::Vec + /// + /// # Errors + /// + /// Each item of the stream has the same error semantics as + /// [`AsyncBufReadExt::read_until`](AsyncBufReadExt::read_until). + /// + /// # Examples + /// + /// ``` + /// # use tokio::io::AsyncBufRead; + /// use tokio::io::AsyncBufReadExt; + /// + /// # async fn dox(my_buf_read: impl AsyncBufRead + Unpin) -> std::io::Result<()> { + /// let mut segments = my_buf_read.split(b'f'); + /// + /// while let Some(segment) = segments.next_segment().await? { + /// println!("length = {}", segment.len()) + /// } + /// # Ok(()) + /// # } + /// ``` + fn split(self, byte: u8) -> Split<Self> + where + Self: Sized + Unpin, + { + split(self, byte) + } + + /// Returns the contents of the internal buffer, filling it with more + /// data from the inner reader if it is empty. + /// + /// This function is a lower-level call. It needs to be paired with the + /// [`consume`] method to function properly. When calling this method, + /// none of the contents will be "read" in the sense that later calling + /// `read` may return the same contents. As such, [`consume`] must be + /// called with the number of bytes that are consumed from this buffer + /// to ensure that the bytes are never returned twice. + /// + /// An empty buffer returned indicates that the stream has reached EOF. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn fill_buf(&mut self) -> io::Result<&[u8]>; + /// ``` + /// + /// # Errors + /// + /// This function will return an I/O error if the underlying reader was + /// read, but returned an error. + /// + /// [`consume`]: crate::io::AsyncBufReadExt::consume + fn fill_buf(&mut self) -> FillBuf<'_, Self> + where + Self: Unpin, + { + fill_buf(self) + } + + /// Tells this buffer that `amt` bytes have been consumed from the + /// buffer, so they should no longer be returned in calls to [`read`]. + /// + /// This function is a lower-level call. It needs to be paired with the + /// [`fill_buf`] method to function properly. This function does not + /// perform any I/O, it simply informs this object that some amount of + /// its buffer, returned from [`fill_buf`], has been consumed and should + /// no longer be returned. As such, this function may do odd things if + /// [`fill_buf`] isn't called before calling it. + /// + /// The `amt` must be less than the number of bytes in the buffer + /// returned by [`fill_buf`]. + /// + /// [`read`]: crate::io::AsyncReadExt::read + /// [`fill_buf`]: crate::io::AsyncBufReadExt::fill_buf + fn consume(&mut self, amt: usize) + where + Self: Unpin, + { + std::pin::Pin::new(self).consume(amt) + } + + /// Returns a stream over the lines of this reader. + /// This method is the async equivalent to [`BufRead::lines`](std::io::BufRead::lines). + /// + /// The stream returned from this function will yield instances of + /// [`io::Result`]`<`[`Option`]`<`[`String`]`>>`. Each string returned will *not* have a newline + /// byte (the 0xA byte) or CRLF (0xD, 0xA bytes) at the end. + /// + /// [`io::Result`]: std::io::Result + /// [`Option`]: core::option::Option + /// [`String`]: String + /// + /// # Errors + /// + /// Each line of the stream has the same error semantics as [`AsyncBufReadExt::read_line`]. + /// + /// # Examples + /// + /// [`std::io::Cursor`][`Cursor`] is a type that implements `BufRead`. In + /// this example, we use [`Cursor`] to iterate over all the lines in a byte + /// slice. + /// + /// [`Cursor`]: std::io::Cursor + /// + /// ``` + /// use tokio::io::AsyncBufReadExt; + /// + /// use std::io::Cursor; + /// + /// #[tokio::main] + /// async fn main() { + /// let cursor = Cursor::new(b"lorem\nipsum\r\ndolor"); + /// + /// let mut lines = cursor.lines(); + /// + /// assert_eq!(lines.next_line().await.unwrap(), Some(String::from("lorem"))); + /// assert_eq!(lines.next_line().await.unwrap(), Some(String::from("ipsum"))); + /// assert_eq!(lines.next_line().await.unwrap(), Some(String::from("dolor"))); + /// assert_eq!(lines.next_line().await.unwrap(), None); + /// } + /// ``` + /// + /// [`AsyncBufReadExt::read_line`]: AsyncBufReadExt::read_line + fn lines(self) -> Lines<Self> + where + Self: Sized, + { + lines(self) + } + } +} + +impl<R: AsyncBufRead + ?Sized> AsyncBufReadExt for R {} diff --git a/third_party/rust/tokio/src/io/util/async_read_ext.rs b/third_party/rust/tokio/src/io/util/async_read_ext.rs new file mode 100644 index 0000000000..df5445c2c6 --- /dev/null +++ b/third_party/rust/tokio/src/io/util/async_read_ext.rs @@ -0,0 +1,1294 @@ +use crate::io::util::chain::{chain, Chain}; +use crate::io::util::read::{read, Read}; +use crate::io::util::read_buf::{read_buf, ReadBuf}; +use crate::io::util::read_exact::{read_exact, ReadExact}; +use crate::io::util::read_int::{ReadF32, ReadF32Le, ReadF64, ReadF64Le}; +use crate::io::util::read_int::{ + ReadI128, ReadI128Le, ReadI16, ReadI16Le, ReadI32, ReadI32Le, ReadI64, ReadI64Le, ReadI8, +}; +use crate::io::util::read_int::{ + ReadU128, ReadU128Le, ReadU16, ReadU16Le, ReadU32, ReadU32Le, ReadU64, ReadU64Le, ReadU8, +}; +use crate::io::util::read_to_end::{read_to_end, ReadToEnd}; +use crate::io::util::read_to_string::{read_to_string, ReadToString}; +use crate::io::util::take::{take, Take}; +use crate::io::AsyncRead; + +use bytes::BufMut; + +cfg_io_util! { + /// Defines numeric reader + macro_rules! read_impl { + ( + $( + $(#[$outer:meta])* + fn $name:ident(&mut self) -> $($fut:ident)*; + )* + ) => { + $( + $(#[$outer])* + fn $name<'a>(&'a mut self) -> $($fut)*<&'a mut Self> where Self: Unpin { + $($fut)*::new(self) + } + )* + } + } + + /// Reads bytes from a source. + /// + /// Implemented as an extension trait, adding utility methods to all + /// [`AsyncRead`] types. Callers will tend to import this trait instead of + /// [`AsyncRead`]. + /// + /// ```no_run + /// use tokio::fs::File; + /// use tokio::io::{self, AsyncReadExt}; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut f = File::open("foo.txt").await?; + /// let mut buffer = [0; 10]; + /// + /// // The `read` method is defined by this trait. + /// let n = f.read(&mut buffer[..]).await?; + /// + /// Ok(()) + /// } + /// ``` + /// + /// See [module][crate::io] documentation for more details. + /// + /// [`AsyncRead`]: AsyncRead + pub trait AsyncReadExt: AsyncRead { + /// Creates a new `AsyncRead` instance that chains this stream with + /// `next`. + /// + /// The returned `AsyncRead` instance will first read all bytes from this object + /// until EOF is encountered. Afterwards the output is equivalent to the + /// output of `next`. + /// + /// # Examples + /// + /// [`File`][crate::fs::File]s implement `AsyncRead`: + /// + /// ```no_run + /// use tokio::fs::File; + /// use tokio::io::{self, AsyncReadExt}; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let f1 = File::open("foo.txt").await?; + /// let f2 = File::open("bar.txt").await?; + /// + /// let mut handle = f1.chain(f2); + /// let mut buffer = String::new(); + /// + /// // read the value into a String. We could use any AsyncRead + /// // method here, this is just one example. + /// handle.read_to_string(&mut buffer).await?; + /// Ok(()) + /// } + /// ``` + fn chain<R>(self, next: R) -> Chain<Self, R> + where + Self: Sized, + R: AsyncRead, + { + chain(self, next) + } + + /// Pulls some bytes from this source into the specified buffer, + /// returning how many bytes were read. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn read(&mut self, buf: &mut [u8]) -> io::Result<usize>; + /// ``` + /// + /// This method does not provide any guarantees about whether it + /// completes immediately or asynchronously. + /// + /// # Return + /// + /// If the return value of this method is `Ok(n)`, then it must be + /// guaranteed that `0 <= n <= buf.len()`. A nonzero `n` value indicates + /// that the buffer `buf` has been filled in with `n` bytes of data from + /// this source. If `n` is `0`, then it can indicate one of two + /// scenarios: + /// + /// 1. This reader has reached its "end of file" and will likely no longer + /// be able to produce bytes. Note that this does not mean that the + /// reader will *always* no longer be able to produce bytes. + /// 2. The buffer specified was 0 bytes in length. + /// + /// No guarantees are provided about the contents of `buf` when this + /// function is called, implementations cannot rely on any property of the + /// contents of `buf` being `true`. It is recommended that *implementations* + /// only write data to `buf` instead of reading its contents. + /// + /// Correspondingly, however, *callers* of this method may not assume + /// any guarantees about how the implementation uses `buf`. It is + /// possible that the code that's supposed to write to the buffer might + /// also read from it. It is your responsibility to make sure that `buf` + /// is initialized before calling `read`. + /// + /// # Errors + /// + /// If this function encounters any form of I/O or other error, an error + /// variant will be returned. If an error is returned then it must be + /// guaranteed that no bytes were read. + /// + /// # Cancel safety + /// + /// This method is cancel safe. If you use it as the event in a + /// [`tokio::select!`](crate::select) statement and some other branch + /// completes first, then it is guaranteed that no data was read. + /// + /// # Examples + /// + /// [`File`][crate::fs::File]s implement `Read`: + /// + /// ```no_run + /// use tokio::fs::File; + /// use tokio::io::{self, AsyncReadExt}; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut f = File::open("foo.txt").await?; + /// let mut buffer = [0; 10]; + /// + /// // read up to 10 bytes + /// let n = f.read(&mut buffer[..]).await?; + /// + /// println!("The bytes: {:?}", &buffer[..n]); + /// Ok(()) + /// } + /// ``` + fn read<'a>(&'a mut self, buf: &'a mut [u8]) -> Read<'a, Self> + where + Self: Unpin, + { + read(self, buf) + } + + /// Pulls some bytes from this source into the specified buffer, + /// advancing the buffer's internal cursor. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn read_buf<B: BufMut>(&mut self, buf: &mut B) -> io::Result<usize>; + /// ``` + /// + /// Usually, only a single `read` syscall is issued, even if there is + /// more space in the supplied buffer. + /// + /// This method does not provide any guarantees about whether it + /// completes immediately or asynchronously. + /// + /// # Return + /// + /// A nonzero `n` value indicates that the buffer `buf` has been filled + /// in with `n` bytes of data from this source. If `n` is `0`, then it + /// can indicate one of two scenarios: + /// + /// 1. This reader has reached its "end of file" and will likely no longer + /// be able to produce bytes. Note that this does not mean that the + /// reader will *always* no longer be able to produce bytes. + /// 2. The buffer specified had a remaining capacity of zero. + /// + /// # Errors + /// + /// If this function encounters any form of I/O or other error, an error + /// variant will be returned. If an error is returned then it must be + /// guaranteed that no bytes were read. + /// + /// # Cancel safety + /// + /// This method is cancel safe. If you use it as the event in a + /// [`tokio::select!`](crate::select) statement and some other branch + /// completes first, then it is guaranteed that no data was read. + /// + /// # Examples + /// + /// [`File`] implements `Read` and [`BytesMut`] implements [`BufMut`]: + /// + /// [`File`]: crate::fs::File + /// [`BytesMut`]: bytes::BytesMut + /// [`BufMut`]: bytes::BufMut + /// + /// ```no_run + /// use tokio::fs::File; + /// use tokio::io::{self, AsyncReadExt}; + /// + /// use bytes::BytesMut; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut f = File::open("foo.txt").await?; + /// let mut buffer = BytesMut::with_capacity(10); + /// + /// assert!(buffer.is_empty()); + /// + /// // read up to 10 bytes, note that the return value is not needed + /// // to access the data that was read as `buffer`'s internal + /// // cursor is updated. + /// f.read_buf(&mut buffer).await?; + /// + /// println!("The bytes: {:?}", &buffer[..]); + /// Ok(()) + /// } + /// ``` + fn read_buf<'a, B>(&'a mut self, buf: &'a mut B) -> ReadBuf<'a, Self, B> + where + Self: Sized + Unpin, + B: BufMut, + { + read_buf(self, buf) + } + + /// Reads the exact number of bytes required to fill `buf`. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn read_exact(&mut self, buf: &mut [u8]) -> io::Result<usize>; + /// ``` + /// + /// This function reads as many bytes as necessary to completely fill + /// the specified buffer `buf`. + /// + /// # Errors + /// + /// If the operation encounters an "end of file" before completely + /// filling the buffer, it returns an error of the kind + /// [`ErrorKind::UnexpectedEof`]. The contents of `buf` are unspecified + /// in this case. + /// + /// If any other read error is encountered then the operation + /// immediately returns. The contents of `buf` are unspecified in this + /// case. + /// + /// If this operation returns an error, it is unspecified how many bytes + /// it has read, but it will never read more than would be necessary to + /// completely fill the buffer. + /// + /// # Cancel safety + /// + /// This method is not cancellation safe. If the method is used as the + /// event in a [`tokio::select!`](crate::select) statement and some + /// other branch completes first, then some data may already have been + /// read into `buf`. + /// + /// # Examples + /// + /// [`File`][crate::fs::File]s implement `Read`: + /// + /// ```no_run + /// use tokio::fs::File; + /// use tokio::io::{self, AsyncReadExt}; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut f = File::open("foo.txt").await?; + /// let mut buffer = [0; 10]; + /// + /// // read exactly 10 bytes + /// f.read_exact(&mut buffer).await?; + /// Ok(()) + /// } + /// ``` + /// + /// [`ErrorKind::UnexpectedEof`]: std::io::ErrorKind::UnexpectedEof + fn read_exact<'a>(&'a mut self, buf: &'a mut [u8]) -> ReadExact<'a, Self> + where + Self: Unpin, + { + read_exact(self, buf) + } + + read_impl! { + /// Reads an unsigned 8 bit integer from the underlying reader. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn read_u8(&mut self) -> io::Result<u8>; + /// ``` + /// + /// It is recommended to use a buffered reader to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncReadExt::read_exact`]. + /// + /// [`AsyncReadExt::read_exact`]: AsyncReadExt::read_exact + /// + /// # Examples + /// + /// Read unsigned 8 bit integers from an `AsyncRead`: + /// + /// ```rust + /// use tokio::io::{self, AsyncReadExt}; + /// + /// use std::io::Cursor; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut reader = Cursor::new(vec![2, 5]); + /// + /// assert_eq!(2, reader.read_u8().await?); + /// assert_eq!(5, reader.read_u8().await?); + /// + /// Ok(()) + /// } + /// ``` + fn read_u8(&mut self) -> ReadU8; + + /// Reads a signed 8 bit integer from the underlying reader. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn read_i8(&mut self) -> io::Result<i8>; + /// ``` + /// + /// It is recommended to use a buffered reader to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncReadExt::read_exact`]. + /// + /// [`AsyncReadExt::read_exact`]: AsyncReadExt::read_exact + /// + /// # Examples + /// + /// Read unsigned 8 bit integers from an `AsyncRead`: + /// + /// ```rust + /// use tokio::io::{self, AsyncReadExt}; + /// + /// use std::io::Cursor; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut reader = Cursor::new(vec![0x02, 0xfb]); + /// + /// assert_eq!(2, reader.read_i8().await?); + /// assert_eq!(-5, reader.read_i8().await?); + /// + /// Ok(()) + /// } + /// ``` + fn read_i8(&mut self) -> ReadI8; + + /// Reads an unsigned 16-bit integer in big-endian order from the + /// underlying reader. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn read_u16(&mut self) -> io::Result<u16>; + /// ``` + /// + /// It is recommended to use a buffered reader to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncReadExt::read_exact`]. + /// + /// [`AsyncReadExt::read_exact`]: AsyncReadExt::read_exact + /// + /// # Examples + /// + /// Read unsigned 16 bit big-endian integers from a `AsyncRead`: + /// + /// ```rust + /// use tokio::io::{self, AsyncReadExt}; + /// + /// use std::io::Cursor; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut reader = Cursor::new(vec![2, 5, 3, 0]); + /// + /// assert_eq!(517, reader.read_u16().await?); + /// assert_eq!(768, reader.read_u16().await?); + /// Ok(()) + /// } + /// ``` + fn read_u16(&mut self) -> ReadU16; + + /// Reads a signed 16-bit integer in big-endian order from the + /// underlying reader. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn read_i16(&mut self) -> io::Result<i16>; + /// ``` + /// + /// It is recommended to use a buffered reader to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncReadExt::read_exact`]. + /// + /// [`AsyncReadExt::read_exact`]: AsyncReadExt::read_exact + /// + /// # Examples + /// + /// Read signed 16 bit big-endian integers from a `AsyncRead`: + /// + /// ```rust + /// use tokio::io::{self, AsyncReadExt}; + /// + /// use std::io::Cursor; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut reader = Cursor::new(vec![0x00, 0xc1, 0xff, 0x7c]); + /// + /// assert_eq!(193, reader.read_i16().await?); + /// assert_eq!(-132, reader.read_i16().await?); + /// Ok(()) + /// } + /// ``` + fn read_i16(&mut self) -> ReadI16; + + /// Reads an unsigned 32-bit integer in big-endian order from the + /// underlying reader. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn read_u32(&mut self) -> io::Result<u32>; + /// ``` + /// + /// It is recommended to use a buffered reader to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncReadExt::read_exact`]. + /// + /// [`AsyncReadExt::read_exact`]: AsyncReadExt::read_exact + /// + /// # Examples + /// + /// Read unsigned 32-bit big-endian integers from a `AsyncRead`: + /// + /// ```rust + /// use tokio::io::{self, AsyncReadExt}; + /// + /// use std::io::Cursor; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut reader = Cursor::new(vec![0x00, 0x00, 0x01, 0x0b]); + /// + /// assert_eq!(267, reader.read_u32().await?); + /// Ok(()) + /// } + /// ``` + fn read_u32(&mut self) -> ReadU32; + + /// Reads a signed 32-bit integer in big-endian order from the + /// underlying reader. + /// + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn read_i32(&mut self) -> io::Result<i32>; + /// ``` + /// + /// It is recommended to use a buffered reader to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncReadExt::read_exact`]. + /// + /// [`AsyncReadExt::read_exact`]: AsyncReadExt::read_exact + /// + /// # Examples + /// + /// Read signed 32-bit big-endian integers from a `AsyncRead`: + /// + /// ```rust + /// use tokio::io::{self, AsyncReadExt}; + /// + /// use std::io::Cursor; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut reader = Cursor::new(vec![0xff, 0xff, 0x7a, 0x33]); + /// + /// assert_eq!(-34253, reader.read_i32().await?); + /// Ok(()) + /// } + /// ``` + fn read_i32(&mut self) -> ReadI32; + + /// Reads an unsigned 64-bit integer in big-endian order from the + /// underlying reader. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn read_u64(&mut self) -> io::Result<u64>; + /// ``` + /// + /// It is recommended to use a buffered reader to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncReadExt::read_exact`]. + /// + /// [`AsyncReadExt::read_exact`]: AsyncReadExt::read_exact + /// + /// # Examples + /// + /// Read unsigned 64-bit big-endian integers from a `AsyncRead`: + /// + /// ```rust + /// use tokio::io::{self, AsyncReadExt}; + /// + /// use std::io::Cursor; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut reader = Cursor::new(vec![ + /// 0x00, 0x03, 0x43, 0x95, 0x4d, 0x60, 0x86, 0x83 + /// ]); + /// + /// assert_eq!(918733457491587, reader.read_u64().await?); + /// Ok(()) + /// } + /// ``` + fn read_u64(&mut self) -> ReadU64; + + /// Reads an signed 64-bit integer in big-endian order from the + /// underlying reader. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn read_i64(&mut self) -> io::Result<i64>; + /// ``` + /// + /// It is recommended to use a buffered reader to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncReadExt::read_exact`]. + /// + /// [`AsyncReadExt::read_exact`]: AsyncReadExt::read_exact + /// + /// # Examples + /// + /// Read signed 64-bit big-endian integers from a `AsyncRead`: + /// + /// ```rust + /// use tokio::io::{self, AsyncReadExt}; + /// + /// use std::io::Cursor; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut reader = Cursor::new(vec![0x80, 0, 0, 0, 0, 0, 0, 0]); + /// + /// assert_eq!(i64::MIN, reader.read_i64().await?); + /// Ok(()) + /// } + /// ``` + fn read_i64(&mut self) -> ReadI64; + + /// Reads an unsigned 128-bit integer in big-endian order from the + /// underlying reader. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn read_u128(&mut self) -> io::Result<u128>; + /// ``` + /// + /// It is recommended to use a buffered reader to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncReadExt::read_exact`]. + /// + /// [`AsyncReadExt::read_exact`]: AsyncReadExt::read_exact + /// + /// # Examples + /// + /// Read unsigned 128-bit big-endian integers from a `AsyncRead`: + /// + /// ```rust + /// use tokio::io::{self, AsyncReadExt}; + /// + /// use std::io::Cursor; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut reader = Cursor::new(vec![ + /// 0x00, 0x03, 0x43, 0x95, 0x4d, 0x60, 0x86, 0x83, + /// 0x00, 0x03, 0x43, 0x95, 0x4d, 0x60, 0x86, 0x83 + /// ]); + /// + /// assert_eq!(16947640962301618749969007319746179, reader.read_u128().await?); + /// Ok(()) + /// } + /// ``` + fn read_u128(&mut self) -> ReadU128; + + /// Reads an signed 128-bit integer in big-endian order from the + /// underlying reader. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn read_i128(&mut self) -> io::Result<i128>; + /// ``` + /// + /// It is recommended to use a buffered reader to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncReadExt::read_exact`]. + /// + /// [`AsyncReadExt::read_exact`]: AsyncReadExt::read_exact + /// + /// # Examples + /// + /// Read signed 128-bit big-endian integers from a `AsyncRead`: + /// + /// ```rust + /// use tokio::io::{self, AsyncReadExt}; + /// + /// use std::io::Cursor; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut reader = Cursor::new(vec![ + /// 0x80, 0, 0, 0, 0, 0, 0, 0, + /// 0, 0, 0, 0, 0, 0, 0, 0 + /// ]); + /// + /// assert_eq!(i128::MIN, reader.read_i128().await?); + /// Ok(()) + /// } + /// ``` + fn read_i128(&mut self) -> ReadI128; + + /// Reads an 32-bit floating point type in big-endian order from the + /// underlying reader. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn read_f32(&mut self) -> io::Result<f32>; + /// ``` + /// + /// It is recommended to use a buffered reader to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncReadExt::read_exact`]. + /// + /// [`AsyncReadExt::read_exact`]: AsyncReadExt::read_exact + /// + /// # Examples + /// + /// Read 32-bit floating point type from a `AsyncRead`: + /// + /// ```rust + /// use tokio::io::{self, AsyncReadExt}; + /// + /// use std::io::Cursor; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut reader = Cursor::new(vec![0xff, 0x7f, 0xff, 0xff]); + /// + /// assert_eq!(f32::MIN, reader.read_f32().await?); + /// Ok(()) + /// } + /// ``` + fn read_f32(&mut self) -> ReadF32; + + /// Reads an 64-bit floating point type in big-endian order from the + /// underlying reader. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn read_f64(&mut self) -> io::Result<f64>; + /// ``` + /// + /// It is recommended to use a buffered reader to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncReadExt::read_exact`]. + /// + /// [`AsyncReadExt::read_exact`]: AsyncReadExt::read_exact + /// + /// # Examples + /// + /// Read 64-bit floating point type from a `AsyncRead`: + /// + /// ```rust + /// use tokio::io::{self, AsyncReadExt}; + /// + /// use std::io::Cursor; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut reader = Cursor::new(vec![ + /// 0xff, 0xef, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff + /// ]); + /// + /// assert_eq!(f64::MIN, reader.read_f64().await?); + /// Ok(()) + /// } + /// ``` + fn read_f64(&mut self) -> ReadF64; + + /// Reads an unsigned 16-bit integer in little-endian order from the + /// underlying reader. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn read_u16_le(&mut self) -> io::Result<u16>; + /// ``` + /// + /// It is recommended to use a buffered reader to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncReadExt::read_exact`]. + /// + /// [`AsyncReadExt::read_exact`]: AsyncReadExt::read_exact + /// + /// # Examples + /// + /// Read unsigned 16 bit little-endian integers from a `AsyncRead`: + /// + /// ```rust + /// use tokio::io::{self, AsyncReadExt}; + /// + /// use std::io::Cursor; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut reader = Cursor::new(vec![2, 5, 3, 0]); + /// + /// assert_eq!(1282, reader.read_u16_le().await?); + /// assert_eq!(3, reader.read_u16_le().await?); + /// Ok(()) + /// } + /// ``` + fn read_u16_le(&mut self) -> ReadU16Le; + + /// Reads a signed 16-bit integer in little-endian order from the + /// underlying reader. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn read_i16_le(&mut self) -> io::Result<i16>; + /// ``` + /// + /// It is recommended to use a buffered reader to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncReadExt::read_exact`]. + /// + /// [`AsyncReadExt::read_exact`]: AsyncReadExt::read_exact + /// + /// # Examples + /// + /// Read signed 16 bit little-endian integers from a `AsyncRead`: + /// + /// ```rust + /// use tokio::io::{self, AsyncReadExt}; + /// + /// use std::io::Cursor; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut reader = Cursor::new(vec![0x00, 0xc1, 0xff, 0x7c]); + /// + /// assert_eq!(-16128, reader.read_i16_le().await?); + /// assert_eq!(31999, reader.read_i16_le().await?); + /// Ok(()) + /// } + /// ``` + fn read_i16_le(&mut self) -> ReadI16Le; + + /// Reads an unsigned 32-bit integer in little-endian order from the + /// underlying reader. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn read_u32_le(&mut self) -> io::Result<u32>; + /// ``` + /// + /// It is recommended to use a buffered reader to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncReadExt::read_exact`]. + /// + /// [`AsyncReadExt::read_exact`]: AsyncReadExt::read_exact + /// + /// # Examples + /// + /// Read unsigned 32-bit little-endian integers from a `AsyncRead`: + /// + /// ```rust + /// use tokio::io::{self, AsyncReadExt}; + /// + /// use std::io::Cursor; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut reader = Cursor::new(vec![0x00, 0x00, 0x01, 0x0b]); + /// + /// assert_eq!(184614912, reader.read_u32_le().await?); + /// Ok(()) + /// } + /// ``` + fn read_u32_le(&mut self) -> ReadU32Le; + + /// Reads a signed 32-bit integer in little-endian order from the + /// underlying reader. + /// + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn read_i32_le(&mut self) -> io::Result<i32>; + /// ``` + /// + /// It is recommended to use a buffered reader to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncReadExt::read_exact`]. + /// + /// [`AsyncReadExt::read_exact`]: AsyncReadExt::read_exact + /// + /// # Examples + /// + /// Read signed 32-bit little-endian integers from a `AsyncRead`: + /// + /// ```rust + /// use tokio::io::{self, AsyncReadExt}; + /// + /// use std::io::Cursor; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut reader = Cursor::new(vec![0xff, 0xff, 0x7a, 0x33]); + /// + /// assert_eq!(863698943, reader.read_i32_le().await?); + /// Ok(()) + /// } + /// ``` + fn read_i32_le(&mut self) -> ReadI32Le; + + /// Reads an unsigned 64-bit integer in little-endian order from the + /// underlying reader. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn read_u64_le(&mut self) -> io::Result<u64>; + /// ``` + /// + /// It is recommended to use a buffered reader to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncReadExt::read_exact`]. + /// + /// [`AsyncReadExt::read_exact`]: AsyncReadExt::read_exact + /// + /// # Examples + /// + /// Read unsigned 64-bit little-endian integers from a `AsyncRead`: + /// + /// ```rust + /// use tokio::io::{self, AsyncReadExt}; + /// + /// use std::io::Cursor; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut reader = Cursor::new(vec![ + /// 0x00, 0x03, 0x43, 0x95, 0x4d, 0x60, 0x86, 0x83 + /// ]); + /// + /// assert_eq!(9477368352180732672, reader.read_u64_le().await?); + /// Ok(()) + /// } + /// ``` + fn read_u64_le(&mut self) -> ReadU64Le; + + /// Reads an signed 64-bit integer in little-endian order from the + /// underlying reader. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn read_i64_le(&mut self) -> io::Result<i64>; + /// ``` + /// + /// It is recommended to use a buffered reader to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncReadExt::read_exact`]. + /// + /// [`AsyncReadExt::read_exact`]: AsyncReadExt::read_exact + /// + /// # Examples + /// + /// Read signed 64-bit little-endian integers from a `AsyncRead`: + /// + /// ```rust + /// use tokio::io::{self, AsyncReadExt}; + /// + /// use std::io::Cursor; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut reader = Cursor::new(vec![0x80, 0, 0, 0, 0, 0, 0, 0]); + /// + /// assert_eq!(128, reader.read_i64_le().await?); + /// Ok(()) + /// } + /// ``` + fn read_i64_le(&mut self) -> ReadI64Le; + + /// Reads an unsigned 128-bit integer in little-endian order from the + /// underlying reader. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn read_u128_le(&mut self) -> io::Result<u128>; + /// ``` + /// + /// It is recommended to use a buffered reader to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncReadExt::read_exact`]. + /// + /// [`AsyncReadExt::read_exact`]: AsyncReadExt::read_exact + /// + /// # Examples + /// + /// Read unsigned 128-bit little-endian integers from a `AsyncRead`: + /// + /// ```rust + /// use tokio::io::{self, AsyncReadExt}; + /// + /// use std::io::Cursor; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut reader = Cursor::new(vec![ + /// 0x00, 0x03, 0x43, 0x95, 0x4d, 0x60, 0x86, 0x83, + /// 0x00, 0x03, 0x43, 0x95, 0x4d, 0x60, 0x86, 0x83 + /// ]); + /// + /// assert_eq!(174826588484952389081207917399662330624, reader.read_u128_le().await?); + /// Ok(()) + /// } + /// ``` + fn read_u128_le(&mut self) -> ReadU128Le; + + /// Reads an signed 128-bit integer in little-endian order from the + /// underlying reader. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn read_i128_le(&mut self) -> io::Result<i128>; + /// ``` + /// + /// It is recommended to use a buffered reader to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncReadExt::read_exact`]. + /// + /// [`AsyncReadExt::read_exact`]: AsyncReadExt::read_exact + /// + /// # Examples + /// + /// Read signed 128-bit little-endian integers from a `AsyncRead`: + /// + /// ```rust + /// use tokio::io::{self, AsyncReadExt}; + /// + /// use std::io::Cursor; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut reader = Cursor::new(vec![ + /// 0x80, 0, 0, 0, 0, 0, 0, 0, + /// 0, 0, 0, 0, 0, 0, 0, 0 + /// ]); + /// + /// assert_eq!(128, reader.read_i128_le().await?); + /// Ok(()) + /// } + /// ``` + fn read_i128_le(&mut self) -> ReadI128Le; + + /// Reads an 32-bit floating point type in little-endian order from the + /// underlying reader. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn read_f32_le(&mut self) -> io::Result<f32>; + /// ``` + /// + /// It is recommended to use a buffered reader to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncReadExt::read_exact`]. + /// + /// [`AsyncReadExt::read_exact`]: AsyncReadExt::read_exact + /// + /// # Examples + /// + /// Read 32-bit floating point type from a `AsyncRead`: + /// + /// ```rust + /// use tokio::io::{self, AsyncReadExt}; + /// + /// use std::io::Cursor; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut reader = Cursor::new(vec![0xff, 0xff, 0x7f, 0xff]); + /// + /// assert_eq!(f32::MIN, reader.read_f32_le().await?); + /// Ok(()) + /// } + /// ``` + fn read_f32_le(&mut self) -> ReadF32Le; + + /// Reads an 64-bit floating point type in little-endian order from the + /// underlying reader. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn read_f64_le(&mut self) -> io::Result<f64>; + /// ``` + /// + /// It is recommended to use a buffered reader to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncReadExt::read_exact`]. + /// + /// [`AsyncReadExt::read_exact`]: AsyncReadExt::read_exact + /// + /// # Examples + /// + /// Read 64-bit floating point type from a `AsyncRead`: + /// + /// ```rust + /// use tokio::io::{self, AsyncReadExt}; + /// + /// use std::io::Cursor; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut reader = Cursor::new(vec![ + /// 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xef, 0xff + /// ]); + /// + /// assert_eq!(f64::MIN, reader.read_f64_le().await?); + /// Ok(()) + /// } + /// ``` + fn read_f64_le(&mut self) -> ReadF64Le; + } + + /// Reads all bytes until EOF in this source, placing them into `buf`. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn read_to_end(&mut self, buf: &mut Vec<u8>) -> io::Result<usize>; + /// ``` + /// + /// All bytes read from this source will be appended to the specified + /// buffer `buf`. This function will continuously call [`read()`] to + /// append more data to `buf` until [`read()`] returns `Ok(0)`. + /// + /// If successful, the total number of bytes read is returned. + /// + /// [`read()`]: AsyncReadExt::read + /// + /// # Errors + /// + /// If a read error is encountered then the `read_to_end` operation + /// immediately completes. Any bytes which have already been read will + /// be appended to `buf`. + /// + /// # Examples + /// + /// [`File`][crate::fs::File]s implement `Read`: + /// + /// ```no_run + /// use tokio::io::{self, AsyncReadExt}; + /// use tokio::fs::File; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut f = File::open("foo.txt").await?; + /// let mut buffer = Vec::new(); + /// + /// // read the whole file + /// f.read_to_end(&mut buffer).await?; + /// Ok(()) + /// } + /// ``` + /// + /// (See also the [`tokio::fs::read`] convenience function for reading from a + /// file.) + /// + /// [`tokio::fs::read`]: fn@crate::fs::read + fn read_to_end<'a>(&'a mut self, buf: &'a mut Vec<u8>) -> ReadToEnd<'a, Self> + where + Self: Unpin, + { + read_to_end(self, buf) + } + + /// Reads all bytes until EOF in this source, appending them to `buf`. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn read_to_string(&mut self, buf: &mut String) -> io::Result<usize>; + /// ``` + /// + /// If successful, the number of bytes which were read and appended to + /// `buf` is returned. + /// + /// # Errors + /// + /// If the data in this stream is *not* valid UTF-8 then an error is + /// returned and `buf` is unchanged. + /// + /// See [`read_to_end`][AsyncReadExt::read_to_end] for other error semantics. + /// + /// # Examples + /// + /// [`File`][crate::fs::File]s implement `Read`: + /// + /// ```no_run + /// use tokio::io::{self, AsyncReadExt}; + /// use tokio::fs::File; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut f = File::open("foo.txt").await?; + /// let mut buffer = String::new(); + /// + /// f.read_to_string(&mut buffer).await?; + /// Ok(()) + /// } + /// ``` + /// + /// (See also the [`crate::fs::read_to_string`] convenience function for + /// reading from a file.) + /// + /// [`crate::fs::read_to_string`]: fn@crate::fs::read_to_string + fn read_to_string<'a>(&'a mut self, dst: &'a mut String) -> ReadToString<'a, Self> + where + Self: Unpin, + { + read_to_string(self, dst) + } + + /// Creates an adaptor which reads at most `limit` bytes from it. + /// + /// This function returns a new instance of `AsyncRead` which will read + /// at most `limit` bytes, after which it will always return EOF + /// (`Ok(0)`). Any read errors will not count towards the number of + /// bytes read and future calls to [`read()`] may succeed. + /// + /// [`read()`]: fn@crate::io::AsyncReadExt::read + /// + /// [read]: AsyncReadExt::read + /// + /// # Examples + /// + /// [`File`][crate::fs::File]s implement `Read`: + /// + /// ```no_run + /// use tokio::io::{self, AsyncReadExt}; + /// use tokio::fs::File; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let f = File::open("foo.txt").await?; + /// let mut buffer = [0; 5]; + /// + /// // read at most five bytes + /// let mut handle = f.take(5); + /// + /// handle.read(&mut buffer).await?; + /// Ok(()) + /// } + /// ``` + fn take(self, limit: u64) -> Take<Self> + where + Self: Sized, + { + take(self, limit) + } + } +} + +impl<R: AsyncRead + ?Sized> AsyncReadExt for R {} diff --git a/third_party/rust/tokio/src/io/util/async_seek_ext.rs b/third_party/rust/tokio/src/io/util/async_seek_ext.rs new file mode 100644 index 0000000000..46b3e6c0d3 --- /dev/null +++ b/third_party/rust/tokio/src/io/util/async_seek_ext.rs @@ -0,0 +1,93 @@ +use crate::io::seek::{seek, Seek}; +use crate::io::AsyncSeek; +use std::io::SeekFrom; + +cfg_io_util! { + /// An extension trait that adds utility methods to [`AsyncSeek`] types. + /// + /// # Examples + /// + /// ``` + /// use std::io::{self, Cursor, SeekFrom}; + /// use tokio::io::{AsyncSeekExt, AsyncReadExt}; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut cursor = Cursor::new(b"abcdefg"); + /// + /// // the `seek` method is defined by this trait + /// cursor.seek(SeekFrom::Start(3)).await?; + /// + /// let mut buf = [0; 1]; + /// let n = cursor.read(&mut buf).await?; + /// assert_eq!(n, 1); + /// assert_eq!(buf, [b'd']); + /// + /// Ok(()) + /// } + /// ``` + /// + /// See [module][crate::io] documentation for more details. + /// + /// [`AsyncSeek`]: AsyncSeek + pub trait AsyncSeekExt: AsyncSeek { + /// Creates a future which will seek an IO object, and then yield the + /// new position in the object and the object itself. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn seek(&mut self, pos: SeekFrom) -> io::Result<u64>; + /// ``` + /// + /// In the case of an error the buffer and the object will be discarded, with + /// the error yielded. + /// + /// # Examples + /// + /// ```no_run + /// use tokio::fs::File; + /// use tokio::io::{AsyncSeekExt, AsyncReadExt}; + /// + /// use std::io::SeekFrom; + /// + /// # async fn dox() -> std::io::Result<()> { + /// let mut file = File::open("foo.txt").await?; + /// file.seek(SeekFrom::Start(6)).await?; + /// + /// let mut contents = vec![0u8; 10]; + /// file.read_exact(&mut contents).await?; + /// # Ok(()) + /// # } + /// ``` + fn seek(&mut self, pos: SeekFrom) -> Seek<'_, Self> + where + Self: Unpin, + { + seek(self, pos) + } + + /// Creates a future which will rewind to the beginning of the stream. + /// + /// This is convenience method, equivalent to to `self.seek(SeekFrom::Start(0))`. + fn rewind(&mut self) -> Seek<'_, Self> + where + Self: Unpin, + { + self.seek(SeekFrom::Start(0)) + } + + /// Creates a future which will return the current seek position from the + /// start of the stream. + /// + /// This is equivalent to `self.seek(SeekFrom::Current(0))`. + fn stream_position(&mut self) -> Seek<'_, Self> + where + Self: Unpin, + { + self.seek(SeekFrom::Current(0)) + } + } +} + +impl<S: AsyncSeek + ?Sized> AsyncSeekExt for S {} diff --git a/third_party/rust/tokio/src/io/util/async_write_ext.rs b/third_party/rust/tokio/src/io/util/async_write_ext.rs new file mode 100644 index 0000000000..93a318315e --- /dev/null +++ b/third_party/rust/tokio/src/io/util/async_write_ext.rs @@ -0,0 +1,1293 @@ +use crate::io::util::flush::{flush, Flush}; +use crate::io::util::shutdown::{shutdown, Shutdown}; +use crate::io::util::write::{write, Write}; +use crate::io::util::write_all::{write_all, WriteAll}; +use crate::io::util::write_all_buf::{write_all_buf, WriteAllBuf}; +use crate::io::util::write_buf::{write_buf, WriteBuf}; +use crate::io::util::write_int::{WriteF32, WriteF32Le, WriteF64, WriteF64Le}; +use crate::io::util::write_int::{ + WriteI128, WriteI128Le, WriteI16, WriteI16Le, WriteI32, WriteI32Le, WriteI64, WriteI64Le, + WriteI8, +}; +use crate::io::util::write_int::{ + WriteU128, WriteU128Le, WriteU16, WriteU16Le, WriteU32, WriteU32Le, WriteU64, WriteU64Le, + WriteU8, +}; +use crate::io::util::write_vectored::{write_vectored, WriteVectored}; +use crate::io::AsyncWrite; +use std::io::IoSlice; + +use bytes::Buf; + +cfg_io_util! { + /// Defines numeric writer. + macro_rules! write_impl { + ( + $( + $(#[$outer:meta])* + fn $name:ident(&mut self, n: $ty:ty) -> $($fut:ident)*; + )* + ) => { + $( + $(#[$outer])* + fn $name<'a>(&'a mut self, n: $ty) -> $($fut)*<&'a mut Self> where Self: Unpin { + $($fut)*::new(self, n) + } + )* + } + } + + /// Writes bytes to a sink. + /// + /// Implemented as an extension trait, adding utility methods to all + /// [`AsyncWrite`] types. Callers will tend to import this trait instead of + /// [`AsyncWrite`]. + /// + /// ```no_run + /// use tokio::io::{self, AsyncWriteExt}; + /// use tokio::fs::File; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let data = b"some bytes"; + /// + /// let mut pos = 0; + /// let mut buffer = File::create("foo.txt").await?; + /// + /// while pos < data.len() { + /// let bytes_written = buffer.write(&data[pos..]).await?; + /// pos += bytes_written; + /// } + /// + /// Ok(()) + /// } + /// ``` + /// + /// See [module][crate::io] documentation for more details. + /// + /// [`AsyncWrite`]: AsyncWrite + pub trait AsyncWriteExt: AsyncWrite { + /// Writes a buffer into this writer, returning how many bytes were + /// written. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn write(&mut self, buf: &[u8]) -> io::Result<usize>; + /// ``` + /// + /// This function will attempt to write the entire contents of `buf`, but + /// the entire write may not succeed, or the write may also generate an + /// error. A call to `write` represents *at most one* attempt to write to + /// any wrapped object. + /// + /// # Return + /// + /// If the return value is `Ok(n)` then it must be guaranteed that `n <= + /// buf.len()`. A return value of `0` typically means that the + /// underlying object is no longer able to accept bytes and will likely + /// not be able to in the future as well, or that the buffer provided is + /// empty. + /// + /// # Errors + /// + /// Each call to `write` may generate an I/O error indicating that the + /// operation could not be completed. If an error is returned then no bytes + /// in the buffer were written to this writer. + /// + /// It is **not** considered an error if the entire buffer could not be + /// written to this writer. + /// + /// # Cancel safety + /// + /// This method is cancellation safe in the sense that if it is used as + /// the event in a [`tokio::select!`](crate::select) statement and some + /// other branch completes first, then it is guaranteed that no data was + /// written to this `AsyncWrite`. + /// + /// # Examples + /// + /// ```no_run + /// use tokio::io::{self, AsyncWriteExt}; + /// use tokio::fs::File; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut file = File::create("foo.txt").await?; + /// + /// // Writes some prefix of the byte string, not necessarily all of it. + /// file.write(b"some bytes").await?; + /// Ok(()) + /// } + /// ``` + fn write<'a>(&'a mut self, src: &'a [u8]) -> Write<'a, Self> + where + Self: Unpin, + { + write(self, src) + } + + /// Like [`write`], except that it writes from a slice of buffers. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn write_vectored(&mut self, bufs: &[IoSlice<'_>]) -> io::Result<usize>; + /// ``` + /// + /// See [`AsyncWrite::poll_write_vectored`] for more details. + /// + /// # Cancel safety + /// + /// This method is cancellation safe in the sense that if it is used as + /// the event in a [`tokio::select!`](crate::select) statement and some + /// other branch completes first, then it is guaranteed that no data was + /// written to this `AsyncWrite`. + /// + /// # Examples + /// + /// ```no_run + /// use tokio::io::{self, AsyncWriteExt}; + /// use tokio::fs::File; + /// use std::io::IoSlice; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut file = File::create("foo.txt").await?; + /// + /// let bufs: &[_] = &[ + /// IoSlice::new(b"hello"), + /// IoSlice::new(b" "), + /// IoSlice::new(b"world"), + /// ]; + /// + /// file.write_vectored(&bufs).await?; + /// + /// Ok(()) + /// } + /// ``` + /// + /// [`write`]: AsyncWriteExt::write + fn write_vectored<'a, 'b>(&'a mut self, bufs: &'a [IoSlice<'b>]) -> WriteVectored<'a, 'b, Self> + where + Self: Unpin, + { + write_vectored(self, bufs) + } + + /// Writes a buffer into this writer, advancing the buffer's internal + /// cursor. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn write_buf<B: Buf>(&mut self, buf: &mut B) -> io::Result<usize>; + /// ``` + /// + /// This function will attempt to write the entire contents of `buf`, but + /// the entire write may not succeed, or the write may also generate an + /// error. After the operation completes, the buffer's + /// internal cursor is advanced by the number of bytes written. A + /// subsequent call to `write_buf` using the **same** `buf` value will + /// resume from the point that the first call to `write_buf` completed. + /// A call to `write_buf` represents *at most one* attempt to write to any + /// wrapped object. + /// + /// # Return + /// + /// If the return value is `Ok(n)` then it must be guaranteed that `n <= + /// buf.len()`. A return value of `0` typically means that the + /// underlying object is no longer able to accept bytes and will likely + /// not be able to in the future as well, or that the buffer provided is + /// empty. + /// + /// # Errors + /// + /// Each call to `write` may generate an I/O error indicating that the + /// operation could not be completed. If an error is returned then no bytes + /// in the buffer were written to this writer. + /// + /// It is **not** considered an error if the entire buffer could not be + /// written to this writer. + /// + /// # Cancel safety + /// + /// This method is cancellation safe in the sense that if it is used as + /// the event in a [`tokio::select!`](crate::select) statement and some + /// other branch completes first, then it is guaranteed that no data was + /// written to this `AsyncWrite`. + /// + /// # Examples + /// + /// [`File`] implements [`AsyncWrite`] and [`Cursor`]`<&[u8]>` implements [`Buf`]: + /// + /// [`File`]: crate::fs::File + /// [`Buf`]: bytes::Buf + /// [`Cursor`]: std::io::Cursor + /// + /// ```no_run + /// use tokio::io::{self, AsyncWriteExt}; + /// use tokio::fs::File; + /// + /// use bytes::Buf; + /// use std::io::Cursor; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut file = File::create("foo.txt").await?; + /// let mut buffer = Cursor::new(b"data to write"); + /// + /// // Loop until the entire contents of the buffer are written to + /// // the file. + /// while buffer.has_remaining() { + /// // Writes some prefix of the byte string, not necessarily + /// // all of it. + /// file.write_buf(&mut buffer).await?; + /// } + /// + /// Ok(()) + /// } + /// ``` + fn write_buf<'a, B>(&'a mut self, src: &'a mut B) -> WriteBuf<'a, Self, B> + where + Self: Sized + Unpin, + B: Buf, + { + write_buf(self, src) + } + + /// Attempts to write an entire buffer into this writer. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn write_all_buf(&mut self, buf: impl Buf) -> Result<(), io::Error> { + /// while buf.has_remaining() { + /// self.write_buf(&mut buf).await?; + /// } + /// Ok(()) + /// } + /// ``` + /// + /// This method will continuously call [`write`] until + /// [`buf.has_remaining()`](bytes::Buf::has_remaining) returns false. This method will not + /// return until the entire buffer has been successfully written or an error occurs. The + /// first error generated will be returned. + /// + /// The buffer is advanced after each chunk is successfully written. After failure, + /// `src.chunk()` will return the chunk that failed to write. + /// + /// # Cancel safety + /// + /// If `write_all_buf` is used as the event in a + /// [`tokio::select!`](crate::select) statement and some other branch + /// completes first, then the data in the provided buffer may have been + /// partially written. However, it is guaranteed that the provided + /// buffer has been [advanced] by the amount of bytes that have been + /// partially written. + /// + /// # Examples + /// + /// [`File`] implements [`AsyncWrite`] and [`Cursor`]`<&[u8]>` implements [`Buf`]: + /// + /// [`File`]: crate::fs::File + /// [`Buf`]: bytes::Buf + /// [`Cursor`]: std::io::Cursor + /// [advanced]: bytes::Buf::advance + /// + /// ```no_run + /// use tokio::io::{self, AsyncWriteExt}; + /// use tokio::fs::File; + /// + /// use std::io::Cursor; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut file = File::create("foo.txt").await?; + /// let mut buffer = Cursor::new(b"data to write"); + /// + /// file.write_all_buf(&mut buffer).await?; + /// Ok(()) + /// } + /// ``` + /// + /// [`write`]: AsyncWriteExt::write + fn write_all_buf<'a, B>(&'a mut self, src: &'a mut B) -> WriteAllBuf<'a, Self, B> + where + Self: Sized + Unpin, + B: Buf, + { + write_all_buf(self, src) + } + + /// Attempts to write an entire buffer into this writer. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn write_all(&mut self, buf: &[u8]) -> io::Result<()>; + /// ``` + /// + /// This method will continuously call [`write`] until there is no more data + /// to be written. This method will not return until the entire buffer + /// has been successfully written or such an error occurs. The first + /// error generated from this method will be returned. + /// + /// # Cancel safety + /// + /// This method is not cancellation safe. If it is used as the event + /// in a [`tokio::select!`](crate::select) statement and some other + /// branch completes first, then the provided buffer may have been + /// partially written, but future calls to `write_all` will start over + /// from the beginning of the buffer. + /// + /// # Errors + /// + /// This function will return the first error that [`write`] returns. + /// + /// # Examples + /// + /// ```no_run + /// use tokio::io::{self, AsyncWriteExt}; + /// use tokio::fs::File; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut file = File::create("foo.txt").await?; + /// + /// file.write_all(b"some bytes").await?; + /// Ok(()) + /// } + /// ``` + /// + /// [`write`]: AsyncWriteExt::write + fn write_all<'a>(&'a mut self, src: &'a [u8]) -> WriteAll<'a, Self> + where + Self: Unpin, + { + write_all(self, src) + } + + write_impl! { + /// Writes an unsigned 8-bit integer to the underlying writer. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn write_u8(&mut self, n: u8) -> io::Result<()>; + /// ``` + /// + /// It is recommended to use a buffered writer to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncWriteExt::write_all`]. + /// + /// [`AsyncWriteExt::write_all`]: AsyncWriteExt::write_all + /// + /// # Examples + /// + /// Write unsigned 8 bit integers to a `AsyncWrite`: + /// + /// ```rust + /// use tokio::io::{self, AsyncWriteExt}; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut writer = Vec::new(); + /// + /// writer.write_u8(2).await?; + /// writer.write_u8(5).await?; + /// + /// assert_eq!(writer, b"\x02\x05"); + /// Ok(()) + /// } + /// ``` + fn write_u8(&mut self, n: u8) -> WriteU8; + + /// Writes an unsigned 8-bit integer to the underlying writer. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn write_i8(&mut self, n: i8) -> io::Result<()>; + /// ``` + /// + /// It is recommended to use a buffered writer to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncWriteExt::write_all`]. + /// + /// [`AsyncWriteExt::write_all`]: AsyncWriteExt::write_all + /// + /// # Examples + /// + /// Write unsigned 8 bit integers to a `AsyncWrite`: + /// + /// ```rust + /// use tokio::io::{self, AsyncWriteExt}; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut writer = Vec::new(); + /// + /// writer.write_u8(2).await?; + /// writer.write_u8(5).await?; + /// + /// assert_eq!(writer, b"\x02\x05"); + /// Ok(()) + /// } + /// ``` + fn write_i8(&mut self, n: i8) -> WriteI8; + + /// Writes an unsigned 16-bit integer in big-endian order to the + /// underlying writer. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn write_u16(&mut self, n: u16) -> io::Result<()>; + /// ``` + /// + /// It is recommended to use a buffered writer to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncWriteExt::write_all`]. + /// + /// [`AsyncWriteExt::write_all`]: AsyncWriteExt::write_all + /// + /// # Examples + /// + /// Write unsigned 16-bit integers to a `AsyncWrite`: + /// + /// ```rust + /// use tokio::io::{self, AsyncWriteExt}; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut writer = Vec::new(); + /// + /// writer.write_u16(517).await?; + /// writer.write_u16(768).await?; + /// + /// assert_eq!(writer, b"\x02\x05\x03\x00"); + /// Ok(()) + /// } + /// ``` + fn write_u16(&mut self, n: u16) -> WriteU16; + + /// Writes a signed 16-bit integer in big-endian order to the + /// underlying writer. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn write_i16(&mut self, n: i16) -> io::Result<()>; + /// ``` + /// + /// It is recommended to use a buffered writer to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncWriteExt::write_all`]. + /// + /// [`AsyncWriteExt::write_all`]: AsyncWriteExt::write_all + /// + /// # Examples + /// + /// Write signed 16-bit integers to a `AsyncWrite`: + /// + /// ```rust + /// use tokio::io::{self, AsyncWriteExt}; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut writer = Vec::new(); + /// + /// writer.write_i16(193).await?; + /// writer.write_i16(-132).await?; + /// + /// assert_eq!(writer, b"\x00\xc1\xff\x7c"); + /// Ok(()) + /// } + /// ``` + fn write_i16(&mut self, n: i16) -> WriteI16; + + /// Writes an unsigned 32-bit integer in big-endian order to the + /// underlying writer. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn write_u32(&mut self, n: u32) -> io::Result<()>; + /// ``` + /// + /// It is recommended to use a buffered writer to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncWriteExt::write_all`]. + /// + /// [`AsyncWriteExt::write_all`]: AsyncWriteExt::write_all + /// + /// # Examples + /// + /// Write unsigned 32-bit integers to a `AsyncWrite`: + /// + /// ```rust + /// use tokio::io::{self, AsyncWriteExt}; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut writer = Vec::new(); + /// + /// writer.write_u32(267).await?; + /// writer.write_u32(1205419366).await?; + /// + /// assert_eq!(writer, b"\x00\x00\x01\x0b\x47\xd9\x3d\x66"); + /// Ok(()) + /// } + /// ``` + fn write_u32(&mut self, n: u32) -> WriteU32; + + /// Writes a signed 32-bit integer in big-endian order to the + /// underlying writer. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn write_i32(&mut self, n: i32) -> io::Result<()>; + /// ``` + /// + /// It is recommended to use a buffered writer to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncWriteExt::write_all`]. + /// + /// [`AsyncWriteExt::write_all`]: AsyncWriteExt::write_all + /// + /// # Examples + /// + /// Write signed 32-bit integers to a `AsyncWrite`: + /// + /// ```rust + /// use tokio::io::{self, AsyncWriteExt}; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut writer = Vec::new(); + /// + /// writer.write_i32(267).await?; + /// writer.write_i32(1205419366).await?; + /// + /// assert_eq!(writer, b"\x00\x00\x01\x0b\x47\xd9\x3d\x66"); + /// Ok(()) + /// } + /// ``` + fn write_i32(&mut self, n: i32) -> WriteI32; + + /// Writes an unsigned 64-bit integer in big-endian order to the + /// underlying writer. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn write_u64(&mut self, n: u64) -> io::Result<()>; + /// ``` + /// + /// It is recommended to use a buffered writer to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncWriteExt::write_all`]. + /// + /// [`AsyncWriteExt::write_all`]: AsyncWriteExt::write_all + /// + /// # Examples + /// + /// Write unsigned 64-bit integers to a `AsyncWrite`: + /// + /// ```rust + /// use tokio::io::{self, AsyncWriteExt}; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut writer = Vec::new(); + /// + /// writer.write_u64(918733457491587).await?; + /// writer.write_u64(143).await?; + /// + /// assert_eq!(writer, b"\x00\x03\x43\x95\x4d\x60\x86\x83\x00\x00\x00\x00\x00\x00\x00\x8f"); + /// Ok(()) + /// } + /// ``` + fn write_u64(&mut self, n: u64) -> WriteU64; + + /// Writes an signed 64-bit integer in big-endian order to the + /// underlying writer. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn write_i64(&mut self, n: i64) -> io::Result<()>; + /// ``` + /// + /// It is recommended to use a buffered writer to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncWriteExt::write_all`]. + /// + /// [`AsyncWriteExt::write_all`]: AsyncWriteExt::write_all + /// + /// # Examples + /// + /// Write signed 64-bit integers to a `AsyncWrite`: + /// + /// ```rust + /// use tokio::io::{self, AsyncWriteExt}; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut writer = Vec::new(); + /// + /// writer.write_i64(i64::MIN).await?; + /// writer.write_i64(i64::MAX).await?; + /// + /// assert_eq!(writer, b"\x80\x00\x00\x00\x00\x00\x00\x00\x7f\xff\xff\xff\xff\xff\xff\xff"); + /// Ok(()) + /// } + /// ``` + fn write_i64(&mut self, n: i64) -> WriteI64; + + /// Writes an unsigned 128-bit integer in big-endian order to the + /// underlying writer. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn write_u128(&mut self, n: u128) -> io::Result<()>; + /// ``` + /// + /// It is recommended to use a buffered writer to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncWriteExt::write_all`]. + /// + /// [`AsyncWriteExt::write_all`]: AsyncWriteExt::write_all + /// + /// # Examples + /// + /// Write unsigned 128-bit integers to a `AsyncWrite`: + /// + /// ```rust + /// use tokio::io::{self, AsyncWriteExt}; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut writer = Vec::new(); + /// + /// writer.write_u128(16947640962301618749969007319746179).await?; + /// + /// assert_eq!(writer, vec![ + /// 0x00, 0x03, 0x43, 0x95, 0x4d, 0x60, 0x86, 0x83, + /// 0x00, 0x03, 0x43, 0x95, 0x4d, 0x60, 0x86, 0x83 + /// ]); + /// Ok(()) + /// } + /// ``` + fn write_u128(&mut self, n: u128) -> WriteU128; + + /// Writes an signed 128-bit integer in big-endian order to the + /// underlying writer. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn write_i128(&mut self, n: i128) -> io::Result<()>; + /// ``` + /// + /// It is recommended to use a buffered writer to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncWriteExt::write_all`]. + /// + /// [`AsyncWriteExt::write_all`]: AsyncWriteExt::write_all + /// + /// # Examples + /// + /// Write signed 128-bit integers to a `AsyncWrite`: + /// + /// ```rust + /// use tokio::io::{self, AsyncWriteExt}; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut writer = Vec::new(); + /// + /// writer.write_i128(i128::MIN).await?; + /// + /// assert_eq!(writer, vec![ + /// 0x80, 0, 0, 0, 0, 0, 0, 0, + /// 0, 0, 0, 0, 0, 0, 0, 0 + /// ]); + /// Ok(()) + /// } + /// ``` + fn write_i128(&mut self, n: i128) -> WriteI128; + + /// Writes an 32-bit floating point type in big-endian order to the + /// underlying writer. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn write_f32(&mut self, n: f32) -> io::Result<()>; + /// ``` + /// + /// It is recommended to use a buffered writer to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncWriteExt::write_all`]. + /// + /// [`AsyncWriteExt::write_all`]: AsyncWriteExt::write_all + /// + /// # Examples + /// + /// Write 32-bit floating point type to a `AsyncWrite`: + /// + /// ```rust + /// use tokio::io::{self, AsyncWriteExt}; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut writer = Vec::new(); + /// + /// writer.write_f32(f32::MIN).await?; + /// + /// assert_eq!(writer, vec![0xff, 0x7f, 0xff, 0xff]); + /// Ok(()) + /// } + /// ``` + fn write_f32(&mut self, n: f32) -> WriteF32; + + /// Writes an 64-bit floating point type in big-endian order to the + /// underlying writer. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn write_f64(&mut self, n: f64) -> io::Result<()>; + /// ``` + /// + /// It is recommended to use a buffered writer to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncWriteExt::write_all`]. + /// + /// [`AsyncWriteExt::write_all`]: AsyncWriteExt::write_all + /// + /// # Examples + /// + /// Write 64-bit floating point type to a `AsyncWrite`: + /// + /// ```rust + /// use tokio::io::{self, AsyncWriteExt}; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut writer = Vec::new(); + /// + /// writer.write_f64(f64::MIN).await?; + /// + /// assert_eq!(writer, vec![ + /// 0xff, 0xef, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff + /// ]); + /// Ok(()) + /// } + /// ``` + fn write_f64(&mut self, n: f64) -> WriteF64; + + /// Writes an unsigned 16-bit integer in little-endian order to the + /// underlying writer. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn write_u16_le(&mut self, n: u16) -> io::Result<()>; + /// ``` + /// + /// It is recommended to use a buffered writer to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncWriteExt::write_all`]. + /// + /// [`AsyncWriteExt::write_all`]: AsyncWriteExt::write_all + /// + /// # Examples + /// + /// Write unsigned 16-bit integers to a `AsyncWrite`: + /// + /// ```rust + /// use tokio::io::{self, AsyncWriteExt}; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut writer = Vec::new(); + /// + /// writer.write_u16_le(517).await?; + /// writer.write_u16_le(768).await?; + /// + /// assert_eq!(writer, b"\x05\x02\x00\x03"); + /// Ok(()) + /// } + /// ``` + fn write_u16_le(&mut self, n: u16) -> WriteU16Le; + + /// Writes a signed 16-bit integer in little-endian order to the + /// underlying writer. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn write_i16_le(&mut self, n: i16) -> io::Result<()>; + /// ``` + /// + /// It is recommended to use a buffered writer to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncWriteExt::write_all`]. + /// + /// [`AsyncWriteExt::write_all`]: AsyncWriteExt::write_all + /// + /// # Examples + /// + /// Write signed 16-bit integers to a `AsyncWrite`: + /// + /// ```rust + /// use tokio::io::{self, AsyncWriteExt}; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut writer = Vec::new(); + /// + /// writer.write_i16_le(193).await?; + /// writer.write_i16_le(-132).await?; + /// + /// assert_eq!(writer, b"\xc1\x00\x7c\xff"); + /// Ok(()) + /// } + /// ``` + fn write_i16_le(&mut self, n: i16) -> WriteI16Le; + + /// Writes an unsigned 32-bit integer in little-endian order to the + /// underlying writer. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn write_u32_le(&mut self, n: u32) -> io::Result<()>; + /// ``` + /// + /// It is recommended to use a buffered writer to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncWriteExt::write_all`]. + /// + /// [`AsyncWriteExt::write_all`]: AsyncWriteExt::write_all + /// + /// # Examples + /// + /// Write unsigned 32-bit integers to a `AsyncWrite`: + /// + /// ```rust + /// use tokio::io::{self, AsyncWriteExt}; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut writer = Vec::new(); + /// + /// writer.write_u32_le(267).await?; + /// writer.write_u32_le(1205419366).await?; + /// + /// assert_eq!(writer, b"\x0b\x01\x00\x00\x66\x3d\xd9\x47"); + /// Ok(()) + /// } + /// ``` + fn write_u32_le(&mut self, n: u32) -> WriteU32Le; + + /// Writes a signed 32-bit integer in little-endian order to the + /// underlying writer. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn write_i32_le(&mut self, n: i32) -> io::Result<()>; + /// ``` + /// + /// It is recommended to use a buffered writer to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncWriteExt::write_all`]. + /// + /// [`AsyncWriteExt::write_all`]: AsyncWriteExt::write_all + /// + /// # Examples + /// + /// Write signed 32-bit integers to a `AsyncWrite`: + /// + /// ```rust + /// use tokio::io::{self, AsyncWriteExt}; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut writer = Vec::new(); + /// + /// writer.write_i32_le(267).await?; + /// writer.write_i32_le(1205419366).await?; + /// + /// assert_eq!(writer, b"\x0b\x01\x00\x00\x66\x3d\xd9\x47"); + /// Ok(()) + /// } + /// ``` + fn write_i32_le(&mut self, n: i32) -> WriteI32Le; + + /// Writes an unsigned 64-bit integer in little-endian order to the + /// underlying writer. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn write_u64_le(&mut self, n: u64) -> io::Result<()>; + /// ``` + /// + /// It is recommended to use a buffered writer to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncWriteExt::write_all`]. + /// + /// [`AsyncWriteExt::write_all`]: AsyncWriteExt::write_all + /// + /// # Examples + /// + /// Write unsigned 64-bit integers to a `AsyncWrite`: + /// + /// ```rust + /// use tokio::io::{self, AsyncWriteExt}; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut writer = Vec::new(); + /// + /// writer.write_u64_le(918733457491587).await?; + /// writer.write_u64_le(143).await?; + /// + /// assert_eq!(writer, b"\x83\x86\x60\x4d\x95\x43\x03\x00\x8f\x00\x00\x00\x00\x00\x00\x00"); + /// Ok(()) + /// } + /// ``` + fn write_u64_le(&mut self, n: u64) -> WriteU64Le; + + /// Writes an signed 64-bit integer in little-endian order to the + /// underlying writer. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn write_i64_le(&mut self, n: i64) -> io::Result<()>; + /// ``` + /// + /// It is recommended to use a buffered writer to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncWriteExt::write_all`]. + /// + /// [`AsyncWriteExt::write_all`]: AsyncWriteExt::write_all + /// + /// # Examples + /// + /// Write signed 64-bit integers to a `AsyncWrite`: + /// + /// ```rust + /// use tokio::io::{self, AsyncWriteExt}; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut writer = Vec::new(); + /// + /// writer.write_i64_le(i64::MIN).await?; + /// writer.write_i64_le(i64::MAX).await?; + /// + /// assert_eq!(writer, b"\x00\x00\x00\x00\x00\x00\x00\x80\xff\xff\xff\xff\xff\xff\xff\x7f"); + /// Ok(()) + /// } + /// ``` + fn write_i64_le(&mut self, n: i64) -> WriteI64Le; + + /// Writes an unsigned 128-bit integer in little-endian order to the + /// underlying writer. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn write_u128_le(&mut self, n: u128) -> io::Result<()>; + /// ``` + /// + /// It is recommended to use a buffered writer to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncWriteExt::write_all`]. + /// + /// [`AsyncWriteExt::write_all`]: AsyncWriteExt::write_all + /// + /// # Examples + /// + /// Write unsigned 128-bit integers to a `AsyncWrite`: + /// + /// ```rust + /// use tokio::io::{self, AsyncWriteExt}; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut writer = Vec::new(); + /// + /// writer.write_u128_le(16947640962301618749969007319746179).await?; + /// + /// assert_eq!(writer, vec![ + /// 0x83, 0x86, 0x60, 0x4d, 0x95, 0x43, 0x03, 0x00, + /// 0x83, 0x86, 0x60, 0x4d, 0x95, 0x43, 0x03, 0x00, + /// ]); + /// Ok(()) + /// } + /// ``` + fn write_u128_le(&mut self, n: u128) -> WriteU128Le; + + /// Writes an signed 128-bit integer in little-endian order to the + /// underlying writer. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn write_i128_le(&mut self, n: i128) -> io::Result<()>; + /// ``` + /// + /// It is recommended to use a buffered writer to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncWriteExt::write_all`]. + /// + /// [`AsyncWriteExt::write_all`]: AsyncWriteExt::write_all + /// + /// # Examples + /// + /// Write signed 128-bit integers to a `AsyncWrite`: + /// + /// ```rust + /// use tokio::io::{self, AsyncWriteExt}; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut writer = Vec::new(); + /// + /// writer.write_i128_le(i128::MIN).await?; + /// + /// assert_eq!(writer, vec![ + /// 0, 0, 0, 0, 0, 0, 0, + /// 0, 0, 0, 0, 0, 0, 0, 0, 0x80 + /// ]); + /// Ok(()) + /// } + /// ``` + fn write_i128_le(&mut self, n: i128) -> WriteI128Le; + + /// Writes an 32-bit floating point type in little-endian order to the + /// underlying writer. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn write_f32_le(&mut self, n: f32) -> io::Result<()>; + /// ``` + /// + /// It is recommended to use a buffered writer to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncWriteExt::write_all`]. + /// + /// [`AsyncWriteExt::write_all`]: AsyncWriteExt::write_all + /// + /// # Examples + /// + /// Write 32-bit floating point type to a `AsyncWrite`: + /// + /// ```rust + /// use tokio::io::{self, AsyncWriteExt}; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut writer = Vec::new(); + /// + /// writer.write_f32_le(f32::MIN).await?; + /// + /// assert_eq!(writer, vec![0xff, 0xff, 0x7f, 0xff]); + /// Ok(()) + /// } + /// ``` + fn write_f32_le(&mut self, n: f32) -> WriteF32Le; + + /// Writes an 64-bit floating point type in little-endian order to the + /// underlying writer. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn write_f64_le(&mut self, n: f64) -> io::Result<()>; + /// ``` + /// + /// It is recommended to use a buffered writer to avoid excessive + /// syscalls. + /// + /// # Errors + /// + /// This method returns the same errors as [`AsyncWriteExt::write_all`]. + /// + /// [`AsyncWriteExt::write_all`]: AsyncWriteExt::write_all + /// + /// # Examples + /// + /// Write 64-bit floating point type to a `AsyncWrite`: + /// + /// ```rust + /// use tokio::io::{self, AsyncWriteExt}; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let mut writer = Vec::new(); + /// + /// writer.write_f64_le(f64::MIN).await?; + /// + /// assert_eq!(writer, vec![ + /// 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xef, 0xff + /// ]); + /// Ok(()) + /// } + /// ``` + fn write_f64_le(&mut self, n: f64) -> WriteF64Le; + } + + /// Flushes this output stream, ensuring that all intermediately buffered + /// contents reach their destination. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn flush(&mut self) -> io::Result<()>; + /// ``` + /// + /// # Errors + /// + /// It is considered an error if not all bytes could be written due to + /// I/O errors or EOF being reached. + /// + /// # Examples + /// + /// ```no_run + /// use tokio::io::{self, BufWriter, AsyncWriteExt}; + /// use tokio::fs::File; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let f = File::create("foo.txt").await?; + /// let mut buffer = BufWriter::new(f); + /// + /// buffer.write_all(b"some bytes").await?; + /// buffer.flush().await?; + /// Ok(()) + /// } + /// ``` + fn flush(&mut self) -> Flush<'_, Self> + where + Self: Unpin, + { + flush(self) + } + + /// Shuts down the output stream, ensuring that the value can be dropped + /// cleanly. + /// + /// Equivalent to: + /// + /// ```ignore + /// async fn shutdown(&mut self) -> io::Result<()>; + /// ``` + /// + /// Similar to [`flush`], all intermediately buffered is written to the + /// underlying stream. Once the operation completes, the caller should + /// no longer attempt to write to the stream. For example, the + /// `TcpStream` implementation will issue a `shutdown(Write)` sys call. + /// + /// [`flush`]: fn@crate::io::AsyncWriteExt::flush + /// + /// # Examples + /// + /// ```no_run + /// use tokio::io::{self, BufWriter, AsyncWriteExt}; + /// use tokio::fs::File; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let f = File::create("foo.txt").await?; + /// let mut buffer = BufWriter::new(f); + /// + /// buffer.write_all(b"some bytes").await?; + /// buffer.shutdown().await?; + /// Ok(()) + /// } + /// ``` + fn shutdown(&mut self) -> Shutdown<'_, Self> + where + Self: Unpin, + { + shutdown(self) + } + } +} + +impl<W: AsyncWrite + ?Sized> AsyncWriteExt for W {} diff --git a/third_party/rust/tokio/src/io/util/buf_reader.rs b/third_party/rust/tokio/src/io/util/buf_reader.rs new file mode 100644 index 0000000000..60879c0fdc --- /dev/null +++ b/third_party/rust/tokio/src/io/util/buf_reader.rs @@ -0,0 +1,311 @@ +use crate::io::util::DEFAULT_BUF_SIZE; +use crate::io::{AsyncBufRead, AsyncRead, AsyncSeek, AsyncWrite, ReadBuf}; + +use pin_project_lite::pin_project; +use std::io::{self, IoSlice, SeekFrom}; +use std::pin::Pin; +use std::task::{Context, Poll}; +use std::{cmp, fmt, mem}; + +pin_project! { + /// The `BufReader` struct adds buffering to any reader. + /// + /// It can be excessively inefficient to work directly with a [`AsyncRead`] + /// instance. A `BufReader` performs large, infrequent reads on the underlying + /// [`AsyncRead`] and maintains an in-memory buffer of the results. + /// + /// `BufReader` can improve the speed of programs that make *small* and + /// *repeated* read calls to the same file or network socket. It does not + /// help when reading very large amounts at once, or reading just one or a few + /// times. It also provides no advantage when reading from a source that is + /// already in memory, like a `Vec<u8>`. + /// + /// When the `BufReader` is dropped, the contents of its buffer will be + /// discarded. Creating multiple instances of a `BufReader` on the same + /// stream can cause data loss. + #[cfg_attr(docsrs, doc(cfg(feature = "io-util")))] + pub struct BufReader<R> { + #[pin] + pub(super) inner: R, + pub(super) buf: Box<[u8]>, + pub(super) pos: usize, + pub(super) cap: usize, + pub(super) seek_state: SeekState, + } +} + +impl<R: AsyncRead> BufReader<R> { + /// Creates a new `BufReader` with a default buffer capacity. The default is currently 8 KB, + /// but may change in the future. + pub fn new(inner: R) -> Self { + Self::with_capacity(DEFAULT_BUF_SIZE, inner) + } + + /// Creates a new `BufReader` with the specified buffer capacity. + pub fn with_capacity(capacity: usize, inner: R) -> Self { + let buffer = vec![0; capacity]; + Self { + inner, + buf: buffer.into_boxed_slice(), + pos: 0, + cap: 0, + seek_state: SeekState::Init, + } + } + + /// Gets a reference to the underlying reader. + /// + /// It is inadvisable to directly read from the underlying reader. + pub fn get_ref(&self) -> &R { + &self.inner + } + + /// Gets a mutable reference to the underlying reader. + /// + /// It is inadvisable to directly read from the underlying reader. + pub fn get_mut(&mut self) -> &mut R { + &mut self.inner + } + + /// Gets a pinned mutable reference to the underlying reader. + /// + /// It is inadvisable to directly read from the underlying reader. + pub fn get_pin_mut(self: Pin<&mut Self>) -> Pin<&mut R> { + self.project().inner + } + + /// Consumes this `BufReader`, returning the underlying reader. + /// + /// Note that any leftover data in the internal buffer is lost. + pub fn into_inner(self) -> R { + self.inner + } + + /// Returns a reference to the internally buffered data. + /// + /// Unlike `fill_buf`, this will not attempt to fill the buffer if it is empty. + pub fn buffer(&self) -> &[u8] { + &self.buf[self.pos..self.cap] + } + + /// Invalidates all data in the internal buffer. + #[inline] + fn discard_buffer(self: Pin<&mut Self>) { + let me = self.project(); + *me.pos = 0; + *me.cap = 0; + } +} + +impl<R: AsyncRead> AsyncRead for BufReader<R> { + fn poll_read( + mut self: Pin<&mut Self>, + cx: &mut Context<'_>, + buf: &mut ReadBuf<'_>, + ) -> Poll<io::Result<()>> { + // If we don't have any buffered data and we're doing a massive read + // (larger than our internal buffer), bypass our internal buffer + // entirely. + if self.pos == self.cap && buf.remaining() >= self.buf.len() { + let res = ready!(self.as_mut().get_pin_mut().poll_read(cx, buf)); + self.discard_buffer(); + return Poll::Ready(res); + } + let rem = ready!(self.as_mut().poll_fill_buf(cx))?; + let amt = std::cmp::min(rem.len(), buf.remaining()); + buf.put_slice(&rem[..amt]); + self.consume(amt); + Poll::Ready(Ok(())) + } +} + +impl<R: AsyncRead> AsyncBufRead for BufReader<R> { + fn poll_fill_buf(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<&[u8]>> { + let me = self.project(); + + // If we've reached the end of our internal buffer then we need to fetch + // some more data from the underlying reader. + // Branch using `>=` instead of the more correct `==` + // to tell the compiler that the pos..cap slice is always valid. + if *me.pos >= *me.cap { + debug_assert!(*me.pos == *me.cap); + let mut buf = ReadBuf::new(me.buf); + ready!(me.inner.poll_read(cx, &mut buf))?; + *me.cap = buf.filled().len(); + *me.pos = 0; + } + Poll::Ready(Ok(&me.buf[*me.pos..*me.cap])) + } + + fn consume(self: Pin<&mut Self>, amt: usize) { + let me = self.project(); + *me.pos = cmp::min(*me.pos + amt, *me.cap); + } +} + +#[derive(Debug, Clone, Copy)] +pub(super) enum SeekState { + /// start_seek has not been called. + Init, + /// start_seek has been called, but poll_complete has not yet been called. + Start(SeekFrom), + /// Waiting for completion of the first poll_complete in the `n.checked_sub(remainder).is_none()` branch. + PendingOverflowed(i64), + /// Waiting for completion of poll_complete. + Pending, +} + +/// Seeks to an offset, in bytes, in the underlying reader. +/// +/// The position used for seeking with `SeekFrom::Current(_)` is the +/// position the underlying reader would be at if the `BufReader` had no +/// internal buffer. +/// +/// Seeking always discards the internal buffer, even if the seek position +/// would otherwise fall within it. This guarantees that calling +/// `.into_inner()` immediately after a seek yields the underlying reader +/// at the same position. +/// +/// See [`AsyncSeek`] for more details. +/// +/// Note: In the edge case where you're seeking with `SeekFrom::Current(n)` +/// where `n` minus the internal buffer length overflows an `i64`, two +/// seeks will be performed instead of one. If the second seek returns +/// `Err`, the underlying reader will be left at the same position it would +/// have if you called `seek` with `SeekFrom::Current(0)`. +impl<R: AsyncRead + AsyncSeek> AsyncSeek for BufReader<R> { + fn start_seek(self: Pin<&mut Self>, pos: SeekFrom) -> io::Result<()> { + // We needs to call seek operation multiple times. + // And we should always call both start_seek and poll_complete, + // as start_seek alone cannot guarantee that the operation will be completed. + // poll_complete receives a Context and returns a Poll, so it cannot be called + // inside start_seek. + *self.project().seek_state = SeekState::Start(pos); + Ok(()) + } + + fn poll_complete(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<u64>> { + let res = match mem::replace(self.as_mut().project().seek_state, SeekState::Init) { + SeekState::Init => { + // 1.x AsyncSeek recommends calling poll_complete before start_seek. + // We don't have to guarantee that the value returned by + // poll_complete called without start_seek is correct, + // so we'll return 0. + return Poll::Ready(Ok(0)); + } + SeekState::Start(SeekFrom::Current(n)) => { + let remainder = (self.cap - self.pos) as i64; + // it should be safe to assume that remainder fits within an i64 as the alternative + // means we managed to allocate 8 exbibytes and that's absurd. + // But it's not out of the realm of possibility for some weird underlying reader to + // support seeking by i64::MIN so we need to handle underflow when subtracting + // remainder. + if let Some(offset) = n.checked_sub(remainder) { + self.as_mut() + .get_pin_mut() + .start_seek(SeekFrom::Current(offset))?; + } else { + // seek backwards by our remainder, and then by the offset + self.as_mut() + .get_pin_mut() + .start_seek(SeekFrom::Current(-remainder))?; + if self.as_mut().get_pin_mut().poll_complete(cx)?.is_pending() { + *self.as_mut().project().seek_state = SeekState::PendingOverflowed(n); + return Poll::Pending; + } + + // https://github.com/rust-lang/rust/pull/61157#issuecomment-495932676 + self.as_mut().discard_buffer(); + + self.as_mut() + .get_pin_mut() + .start_seek(SeekFrom::Current(n))?; + } + self.as_mut().get_pin_mut().poll_complete(cx)? + } + SeekState::PendingOverflowed(n) => { + if self.as_mut().get_pin_mut().poll_complete(cx)?.is_pending() { + *self.as_mut().project().seek_state = SeekState::PendingOverflowed(n); + return Poll::Pending; + } + + // https://github.com/rust-lang/rust/pull/61157#issuecomment-495932676 + self.as_mut().discard_buffer(); + + self.as_mut() + .get_pin_mut() + .start_seek(SeekFrom::Current(n))?; + self.as_mut().get_pin_mut().poll_complete(cx)? + } + SeekState::Start(pos) => { + // Seeking with Start/End doesn't care about our buffer length. + self.as_mut().get_pin_mut().start_seek(pos)?; + self.as_mut().get_pin_mut().poll_complete(cx)? + } + SeekState::Pending => self.as_mut().get_pin_mut().poll_complete(cx)?, + }; + + match res { + Poll::Ready(res) => { + self.discard_buffer(); + Poll::Ready(Ok(res)) + } + Poll::Pending => { + *self.as_mut().project().seek_state = SeekState::Pending; + Poll::Pending + } + } + } +} + +impl<R: AsyncRead + AsyncWrite> AsyncWrite for BufReader<R> { + fn poll_write( + self: Pin<&mut Self>, + cx: &mut Context<'_>, + buf: &[u8], + ) -> Poll<io::Result<usize>> { + self.get_pin_mut().poll_write(cx, buf) + } + + fn poll_write_vectored( + self: Pin<&mut Self>, + cx: &mut Context<'_>, + bufs: &[IoSlice<'_>], + ) -> Poll<io::Result<usize>> { + self.get_pin_mut().poll_write_vectored(cx, bufs) + } + + fn is_write_vectored(&self) -> bool { + self.get_ref().is_write_vectored() + } + + fn poll_flush(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<()>> { + self.get_pin_mut().poll_flush(cx) + } + + fn poll_shutdown(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<()>> { + self.get_pin_mut().poll_shutdown(cx) + } +} + +impl<R: fmt::Debug> fmt::Debug for BufReader<R> { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + f.debug_struct("BufReader") + .field("reader", &self.inner) + .field( + "buffer", + &format_args!("{}/{}", self.cap - self.pos, self.buf.len()), + ) + .finish() + } +} + +#[cfg(test)] +mod tests { + use super::*; + + #[test] + fn assert_unpin() { + crate::is_unpin::<BufReader<()>>(); + } +} diff --git a/third_party/rust/tokio/src/io/util/buf_stream.rs b/third_party/rust/tokio/src/io/util/buf_stream.rs new file mode 100644 index 0000000000..595c142aca --- /dev/null +++ b/third_party/rust/tokio/src/io/util/buf_stream.rs @@ -0,0 +1,207 @@ +use crate::io::util::{BufReader, BufWriter}; +use crate::io::{AsyncBufRead, AsyncRead, AsyncSeek, AsyncWrite, ReadBuf}; + +use pin_project_lite::pin_project; +use std::io::{self, IoSlice, SeekFrom}; +use std::pin::Pin; +use std::task::{Context, Poll}; + +pin_project! { + /// Wraps a type that is [`AsyncWrite`] and [`AsyncRead`], and buffers its input and output. + /// + /// It can be excessively inefficient to work directly with something that implements [`AsyncWrite`] + /// and [`AsyncRead`]. For example, every `write`, however small, has to traverse the syscall + /// interface, and similarly, every read has to do the same. The [`BufWriter`] and [`BufReader`] + /// types aid with these problems respectively, but do so in only one direction. `BufStream` wraps + /// one in the other so that both directions are buffered. See their documentation for details. + #[derive(Debug)] + #[cfg_attr(docsrs, doc(cfg(feature = "io-util")))] + pub struct BufStream<RW> { + #[pin] + inner: BufReader<BufWriter<RW>>, + } +} + +impl<RW: AsyncRead + AsyncWrite> BufStream<RW> { + /// Wraps a type in both [`BufWriter`] and [`BufReader`]. + /// + /// See the documentation for those types and [`BufStream`] for details. + pub fn new(stream: RW) -> BufStream<RW> { + BufStream { + inner: BufReader::new(BufWriter::new(stream)), + } + } + + /// Creates a `BufStream` with the specified [`BufReader`] capacity and [`BufWriter`] + /// capacity. + /// + /// See the documentation for those types and [`BufStream`] for details. + pub fn with_capacity( + reader_capacity: usize, + writer_capacity: usize, + stream: RW, + ) -> BufStream<RW> { + BufStream { + inner: BufReader::with_capacity( + reader_capacity, + BufWriter::with_capacity(writer_capacity, stream), + ), + } + } + + /// Gets a reference to the underlying I/O object. + /// + /// It is inadvisable to directly read from the underlying I/O object. + pub fn get_ref(&self) -> &RW { + self.inner.get_ref().get_ref() + } + + /// Gets a mutable reference to the underlying I/O object. + /// + /// It is inadvisable to directly read from the underlying I/O object. + pub fn get_mut(&mut self) -> &mut RW { + self.inner.get_mut().get_mut() + } + + /// Gets a pinned mutable reference to the underlying I/O object. + /// + /// It is inadvisable to directly read from the underlying I/O object. + pub fn get_pin_mut(self: Pin<&mut Self>) -> Pin<&mut RW> { + self.project().inner.get_pin_mut().get_pin_mut() + } + + /// Consumes this `BufStream`, returning the underlying I/O object. + /// + /// Note that any leftover data in the internal buffer is lost. + pub fn into_inner(self) -> RW { + self.inner.into_inner().into_inner() + } +} + +impl<RW> From<BufReader<BufWriter<RW>>> for BufStream<RW> { + fn from(b: BufReader<BufWriter<RW>>) -> Self { + BufStream { inner: b } + } +} + +impl<RW> From<BufWriter<BufReader<RW>>> for BufStream<RW> { + fn from(b: BufWriter<BufReader<RW>>) -> Self { + // we need to "invert" the reader and writer + let BufWriter { + inner: + BufReader { + inner, + buf: rbuf, + pos, + cap, + seek_state: rseek_state, + }, + buf: wbuf, + written, + seek_state: wseek_state, + } = b; + + BufStream { + inner: BufReader { + inner: BufWriter { + inner, + buf: wbuf, + written, + seek_state: wseek_state, + }, + buf: rbuf, + pos, + cap, + seek_state: rseek_state, + }, + } + } +} + +impl<RW: AsyncRead + AsyncWrite> AsyncWrite for BufStream<RW> { + fn poll_write( + self: Pin<&mut Self>, + cx: &mut Context<'_>, + buf: &[u8], + ) -> Poll<io::Result<usize>> { + self.project().inner.poll_write(cx, buf) + } + + fn poll_write_vectored( + self: Pin<&mut Self>, + cx: &mut Context<'_>, + bufs: &[IoSlice<'_>], + ) -> Poll<io::Result<usize>> { + self.project().inner.poll_write_vectored(cx, bufs) + } + + fn is_write_vectored(&self) -> bool { + self.inner.is_write_vectored() + } + + fn poll_flush(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<()>> { + self.project().inner.poll_flush(cx) + } + + fn poll_shutdown(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<()>> { + self.project().inner.poll_shutdown(cx) + } +} + +impl<RW: AsyncRead + AsyncWrite> AsyncRead for BufStream<RW> { + fn poll_read( + self: Pin<&mut Self>, + cx: &mut Context<'_>, + buf: &mut ReadBuf<'_>, + ) -> Poll<io::Result<()>> { + self.project().inner.poll_read(cx, buf) + } +} + +/// Seek to an offset, in bytes, in the underlying stream. +/// +/// The position used for seeking with `SeekFrom::Current(_)` is the +/// position the underlying stream would be at if the `BufStream` had no +/// internal buffer. +/// +/// Seeking always discards the internal buffer, even if the seek position +/// would otherwise fall within it. This guarantees that calling +/// `.into_inner()` immediately after a seek yields the underlying reader +/// at the same position. +/// +/// See [`AsyncSeek`] for more details. +/// +/// Note: In the edge case where you're seeking with `SeekFrom::Current(n)` +/// where `n` minus the internal buffer length overflows an `i64`, two +/// seeks will be performed instead of one. If the second seek returns +/// `Err`, the underlying reader will be left at the same position it would +/// have if you called `seek` with `SeekFrom::Current(0)`. +impl<RW: AsyncRead + AsyncWrite + AsyncSeek> AsyncSeek for BufStream<RW> { + fn start_seek(self: Pin<&mut Self>, position: SeekFrom) -> io::Result<()> { + self.project().inner.start_seek(position) + } + + fn poll_complete(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<u64>> { + self.project().inner.poll_complete(cx) + } +} + +impl<RW: AsyncRead + AsyncWrite> AsyncBufRead for BufStream<RW> { + fn poll_fill_buf(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<&[u8]>> { + self.project().inner.poll_fill_buf(cx) + } + + fn consume(self: Pin<&mut Self>, amt: usize) { + self.project().inner.consume(amt) + } +} + +#[cfg(test)] +mod tests { + use super::*; + + #[test] + fn assert_unpin() { + crate::is_unpin::<BufStream<()>>(); + } +} diff --git a/third_party/rust/tokio/src/io/util/buf_writer.rs b/third_party/rust/tokio/src/io/util/buf_writer.rs new file mode 100644 index 0000000000..8dd1bba60a --- /dev/null +++ b/third_party/rust/tokio/src/io/util/buf_writer.rs @@ -0,0 +1,310 @@ +use crate::io::util::DEFAULT_BUF_SIZE; +use crate::io::{AsyncBufRead, AsyncRead, AsyncSeek, AsyncWrite, ReadBuf}; + +use pin_project_lite::pin_project; +use std::fmt; +use std::io::{self, IoSlice, SeekFrom, Write}; +use std::pin::Pin; +use std::task::{Context, Poll}; + +pin_project! { + /// Wraps a writer and buffers its output. + /// + /// It can be excessively inefficient to work directly with something that + /// implements [`AsyncWrite`]. A `BufWriter` keeps an in-memory buffer of data and + /// writes it to an underlying writer in large, infrequent batches. + /// + /// `BufWriter` can improve the speed of programs that make *small* and + /// *repeated* write calls to the same file or network socket. It does not + /// help when writing very large amounts at once, or writing just one or a few + /// times. It also provides no advantage when writing to a destination that is + /// in memory, like a `Vec<u8>`. + /// + /// When the `BufWriter` is dropped, the contents of its buffer will be + /// discarded. Creating multiple instances of a `BufWriter` on the same + /// stream can cause data loss. If you need to write out the contents of its + /// buffer, you must manually call flush before the writer is dropped. + /// + /// [`AsyncWrite`]: AsyncWrite + /// [`flush`]: super::AsyncWriteExt::flush + /// + #[cfg_attr(docsrs, doc(cfg(feature = "io-util")))] + pub struct BufWriter<W> { + #[pin] + pub(super) inner: W, + pub(super) buf: Vec<u8>, + pub(super) written: usize, + pub(super) seek_state: SeekState, + } +} + +impl<W: AsyncWrite> BufWriter<W> { + /// Creates a new `BufWriter` with a default buffer capacity. The default is currently 8 KB, + /// but may change in the future. + pub fn new(inner: W) -> Self { + Self::with_capacity(DEFAULT_BUF_SIZE, inner) + } + + /// Creates a new `BufWriter` with the specified buffer capacity. + pub fn with_capacity(cap: usize, inner: W) -> Self { + Self { + inner, + buf: Vec::with_capacity(cap), + written: 0, + seek_state: SeekState::Init, + } + } + + fn flush_buf(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<()>> { + let mut me = self.project(); + + let len = me.buf.len(); + let mut ret = Ok(()); + while *me.written < len { + match ready!(me.inner.as_mut().poll_write(cx, &me.buf[*me.written..])) { + Ok(0) => { + ret = Err(io::Error::new( + io::ErrorKind::WriteZero, + "failed to write the buffered data", + )); + break; + } + Ok(n) => *me.written += n, + Err(e) => { + ret = Err(e); + break; + } + } + } + if *me.written > 0 { + me.buf.drain(..*me.written); + } + *me.written = 0; + Poll::Ready(ret) + } + + /// Gets a reference to the underlying writer. + pub fn get_ref(&self) -> &W { + &self.inner + } + + /// Gets a mutable reference to the underlying writer. + /// + /// It is inadvisable to directly write to the underlying writer. + pub fn get_mut(&mut self) -> &mut W { + &mut self.inner + } + + /// Gets a pinned mutable reference to the underlying writer. + /// + /// It is inadvisable to directly write to the underlying writer. + pub fn get_pin_mut(self: Pin<&mut Self>) -> Pin<&mut W> { + self.project().inner + } + + /// Consumes this `BufWriter`, returning the underlying writer. + /// + /// Note that any leftover data in the internal buffer is lost. + pub fn into_inner(self) -> W { + self.inner + } + + /// Returns a reference to the internally buffered data. + pub fn buffer(&self) -> &[u8] { + &self.buf + } +} + +impl<W: AsyncWrite> AsyncWrite for BufWriter<W> { + fn poll_write( + mut self: Pin<&mut Self>, + cx: &mut Context<'_>, + buf: &[u8], + ) -> Poll<io::Result<usize>> { + if self.buf.len() + buf.len() > self.buf.capacity() { + ready!(self.as_mut().flush_buf(cx))?; + } + + let me = self.project(); + if buf.len() >= me.buf.capacity() { + me.inner.poll_write(cx, buf) + } else { + Poll::Ready(me.buf.write(buf)) + } + } + + fn poll_write_vectored( + mut self: Pin<&mut Self>, + cx: &mut Context<'_>, + mut bufs: &[IoSlice<'_>], + ) -> Poll<io::Result<usize>> { + if self.inner.is_write_vectored() { + let total_len = bufs + .iter() + .fold(0usize, |acc, b| acc.saturating_add(b.len())); + if total_len > self.buf.capacity() - self.buf.len() { + ready!(self.as_mut().flush_buf(cx))?; + } + let me = self.as_mut().project(); + if total_len >= me.buf.capacity() { + // It's more efficient to pass the slices directly to the + // underlying writer than to buffer them. + // The case when the total_len calculation saturates at + // usize::MAX is also handled here. + me.inner.poll_write_vectored(cx, bufs) + } else { + bufs.iter().for_each(|b| me.buf.extend_from_slice(b)); + Poll::Ready(Ok(total_len)) + } + } else { + // Remove empty buffers at the beginning of bufs. + while bufs.first().map(|buf| buf.len()) == Some(0) { + bufs = &bufs[1..]; + } + if bufs.is_empty() { + return Poll::Ready(Ok(0)); + } + // Flush if the first buffer doesn't fit. + let first_len = bufs[0].len(); + if first_len > self.buf.capacity() - self.buf.len() { + ready!(self.as_mut().flush_buf(cx))?; + debug_assert!(self.buf.is_empty()); + } + let me = self.as_mut().project(); + if first_len >= me.buf.capacity() { + // The slice is at least as large as the buffering capacity, + // so it's better to write it directly, bypassing the buffer. + debug_assert!(me.buf.is_empty()); + return me.inner.poll_write(cx, &bufs[0]); + } else { + me.buf.extend_from_slice(&bufs[0]); + bufs = &bufs[1..]; + } + let mut total_written = first_len; + debug_assert!(total_written != 0); + // Append the buffers that fit in the internal buffer. + for buf in bufs { + if buf.len() > me.buf.capacity() - me.buf.len() { + break; + } else { + me.buf.extend_from_slice(buf); + total_written += buf.len(); + } + } + Poll::Ready(Ok(total_written)) + } + } + + fn is_write_vectored(&self) -> bool { + true + } + + fn poll_flush(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<()>> { + ready!(self.as_mut().flush_buf(cx))?; + self.get_pin_mut().poll_flush(cx) + } + + fn poll_shutdown(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<()>> { + ready!(self.as_mut().flush_buf(cx))?; + self.get_pin_mut().poll_shutdown(cx) + } +} + +#[derive(Debug, Clone, Copy)] +pub(super) enum SeekState { + /// start_seek has not been called. + Init, + /// start_seek has been called, but poll_complete has not yet been called. + Start(SeekFrom), + /// Waiting for completion of poll_complete. + Pending, +} + +/// Seek to the offset, in bytes, in the underlying writer. +/// +/// Seeking always writes out the internal buffer before seeking. +impl<W: AsyncWrite + AsyncSeek> AsyncSeek for BufWriter<W> { + fn start_seek(self: Pin<&mut Self>, pos: SeekFrom) -> io::Result<()> { + // We need to flush the internal buffer before seeking. + // It receives a `Context` and returns a `Poll`, so it cannot be called + // inside `start_seek`. + *self.project().seek_state = SeekState::Start(pos); + Ok(()) + } + + fn poll_complete(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<u64>> { + let pos = match self.seek_state { + SeekState::Init => { + return self.project().inner.poll_complete(cx); + } + SeekState::Start(pos) => Some(pos), + SeekState::Pending => None, + }; + + // Flush the internal buffer before seeking. + ready!(self.as_mut().flush_buf(cx))?; + + let mut me = self.project(); + if let Some(pos) = pos { + // Ensure previous seeks have finished before starting a new one + ready!(me.inner.as_mut().poll_complete(cx))?; + if let Err(e) = me.inner.as_mut().start_seek(pos) { + *me.seek_state = SeekState::Init; + return Poll::Ready(Err(e)); + } + } + match me.inner.poll_complete(cx) { + Poll::Ready(res) => { + *me.seek_state = SeekState::Init; + Poll::Ready(res) + } + Poll::Pending => { + *me.seek_state = SeekState::Pending; + Poll::Pending + } + } + } +} + +impl<W: AsyncWrite + AsyncRead> AsyncRead for BufWriter<W> { + fn poll_read( + self: Pin<&mut Self>, + cx: &mut Context<'_>, + buf: &mut ReadBuf<'_>, + ) -> Poll<io::Result<()>> { + self.get_pin_mut().poll_read(cx, buf) + } +} + +impl<W: AsyncWrite + AsyncBufRead> AsyncBufRead for BufWriter<W> { + fn poll_fill_buf(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<&[u8]>> { + self.get_pin_mut().poll_fill_buf(cx) + } + + fn consume(self: Pin<&mut Self>, amt: usize) { + self.get_pin_mut().consume(amt) + } +} + +impl<W: fmt::Debug> fmt::Debug for BufWriter<W> { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + f.debug_struct("BufWriter") + .field("writer", &self.inner) + .field( + "buffer", + &format_args!("{}/{}", self.buf.len(), self.buf.capacity()), + ) + .field("written", &self.written) + .finish() + } +} + +#[cfg(test)] +mod tests { + use super::*; + + #[test] + fn assert_unpin() { + crate::is_unpin::<BufWriter<()>>(); + } +} diff --git a/third_party/rust/tokio/src/io/util/chain.rs b/third_party/rust/tokio/src/io/util/chain.rs new file mode 100644 index 0000000000..84f37fc7d4 --- /dev/null +++ b/third_party/rust/tokio/src/io/util/chain.rs @@ -0,0 +1,144 @@ +use crate::io::{AsyncBufRead, AsyncRead, ReadBuf}; + +use pin_project_lite::pin_project; +use std::fmt; +use std::io; +use std::pin::Pin; +use std::task::{Context, Poll}; + +pin_project! { + /// Stream for the [`chain`](super::AsyncReadExt::chain) method. + #[must_use = "streams do nothing unless polled"] + #[cfg_attr(docsrs, doc(cfg(feature = "io-util")))] + pub struct Chain<T, U> { + #[pin] + first: T, + #[pin] + second: U, + done_first: bool, + } +} + +pub(super) fn chain<T, U>(first: T, second: U) -> Chain<T, U> +where + T: AsyncRead, + U: AsyncRead, +{ + Chain { + first, + second, + done_first: false, + } +} + +impl<T, U> Chain<T, U> +where + T: AsyncRead, + U: AsyncRead, +{ + /// Gets references to the underlying readers in this `Chain`. + pub fn get_ref(&self) -> (&T, &U) { + (&self.first, &self.second) + } + + /// Gets mutable references to the underlying readers in this `Chain`. + /// + /// Care should be taken to avoid modifying the internal I/O state of the + /// underlying readers as doing so may corrupt the internal state of this + /// `Chain`. + pub fn get_mut(&mut self) -> (&mut T, &mut U) { + (&mut self.first, &mut self.second) + } + + /// Gets pinned mutable references to the underlying readers in this `Chain`. + /// + /// Care should be taken to avoid modifying the internal I/O state of the + /// underlying readers as doing so may corrupt the internal state of this + /// `Chain`. + pub fn get_pin_mut(self: Pin<&mut Self>) -> (Pin<&mut T>, Pin<&mut U>) { + let me = self.project(); + (me.first, me.second) + } + + /// Consumes the `Chain`, returning the wrapped readers. + pub fn into_inner(self) -> (T, U) { + (self.first, self.second) + } +} + +impl<T, U> fmt::Debug for Chain<T, U> +where + T: fmt::Debug, + U: fmt::Debug, +{ + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + f.debug_struct("Chain") + .field("t", &self.first) + .field("u", &self.second) + .finish() + } +} + +impl<T, U> AsyncRead for Chain<T, U> +where + T: AsyncRead, + U: AsyncRead, +{ + fn poll_read( + self: Pin<&mut Self>, + cx: &mut Context<'_>, + buf: &mut ReadBuf<'_>, + ) -> Poll<io::Result<()>> { + let me = self.project(); + + if !*me.done_first { + let rem = buf.remaining(); + ready!(me.first.poll_read(cx, buf))?; + if buf.remaining() == rem { + *me.done_first = true; + } else { + return Poll::Ready(Ok(())); + } + } + me.second.poll_read(cx, buf) + } +} + +impl<T, U> AsyncBufRead for Chain<T, U> +where + T: AsyncBufRead, + U: AsyncBufRead, +{ + fn poll_fill_buf(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<&[u8]>> { + let me = self.project(); + + if !*me.done_first { + match ready!(me.first.poll_fill_buf(cx)?) { + buf if buf.is_empty() => { + *me.done_first = true; + } + buf => return Poll::Ready(Ok(buf)), + } + } + me.second.poll_fill_buf(cx) + } + + fn consume(self: Pin<&mut Self>, amt: usize) { + let me = self.project(); + if !*me.done_first { + me.first.consume(amt) + } else { + me.second.consume(amt) + } + } +} + +#[cfg(test)] +mod tests { + use super::*; + + #[test] + fn assert_unpin() { + crate::is_unpin::<Chain<(), ()>>(); + } +} diff --git a/third_party/rust/tokio/src/io/util/copy.rs b/third_party/rust/tokio/src/io/util/copy.rs new file mode 100644 index 0000000000..d0ab7cb140 --- /dev/null +++ b/third_party/rust/tokio/src/io/util/copy.rs @@ -0,0 +1,175 @@ +use crate::io::{AsyncRead, AsyncWrite, ReadBuf}; + +use std::future::Future; +use std::io; +use std::pin::Pin; +use std::task::{Context, Poll}; + +#[derive(Debug)] +pub(super) struct CopyBuffer { + read_done: bool, + need_flush: bool, + pos: usize, + cap: usize, + amt: u64, + buf: Box<[u8]>, +} + +impl CopyBuffer { + pub(super) fn new() -> Self { + Self { + read_done: false, + need_flush: false, + pos: 0, + cap: 0, + amt: 0, + buf: vec![0; super::DEFAULT_BUF_SIZE].into_boxed_slice(), + } + } + + pub(super) fn poll_copy<R, W>( + &mut self, + cx: &mut Context<'_>, + mut reader: Pin<&mut R>, + mut writer: Pin<&mut W>, + ) -> Poll<io::Result<u64>> + where + R: AsyncRead + ?Sized, + W: AsyncWrite + ?Sized, + { + loop { + // If our buffer is empty, then we need to read some data to + // continue. + if self.pos == self.cap && !self.read_done { + let me = &mut *self; + let mut buf = ReadBuf::new(&mut me.buf); + + match reader.as_mut().poll_read(cx, &mut buf) { + Poll::Ready(Ok(_)) => (), + Poll::Ready(Err(err)) => return Poll::Ready(Err(err)), + Poll::Pending => { + // Try flushing when the reader has no progress to avoid deadlock + // when the reader depends on buffered writer. + if self.need_flush { + ready!(writer.as_mut().poll_flush(cx))?; + self.need_flush = false; + } + + return Poll::Pending; + } + } + + let n = buf.filled().len(); + if n == 0 { + self.read_done = true; + } else { + self.pos = 0; + self.cap = n; + } + } + + // If our buffer has some data, let's write it out! + while self.pos < self.cap { + let me = &mut *self; + let i = ready!(writer.as_mut().poll_write(cx, &me.buf[me.pos..me.cap]))?; + if i == 0 { + return Poll::Ready(Err(io::Error::new( + io::ErrorKind::WriteZero, + "write zero byte into writer", + ))); + } else { + self.pos += i; + self.amt += i as u64; + self.need_flush = true; + } + } + + // If pos larger than cap, this loop will never stop. + // In particular, user's wrong poll_write implementation returning + // incorrect written length may lead to thread blocking. + debug_assert!( + self.pos <= self.cap, + "writer returned length larger than input slice" + ); + + // If we've written all the data and we've seen EOF, flush out the + // data and finish the transfer. + if self.pos == self.cap && self.read_done { + ready!(writer.as_mut().poll_flush(cx))?; + return Poll::Ready(Ok(self.amt)); + } + } + } +} + +/// A future that asynchronously copies the entire contents of a reader into a +/// writer. +#[derive(Debug)] +#[must_use = "futures do nothing unless you `.await` or poll them"] +struct Copy<'a, R: ?Sized, W: ?Sized> { + reader: &'a mut R, + writer: &'a mut W, + buf: CopyBuffer, +} + +cfg_io_util! { + /// Asynchronously copies the entire contents of a reader into a writer. + /// + /// This function returns a future that will continuously read data from + /// `reader` and then write it into `writer` in a streaming fashion until + /// `reader` returns EOF. + /// + /// On success, the total number of bytes that were copied from `reader` to + /// `writer` is returned. + /// + /// This is an asynchronous version of [`std::io::copy`][std]. + /// + /// [std]: std::io::copy + /// + /// # Errors + /// + /// The returned future will return an error immediately if any call to + /// `poll_read` or `poll_write` returns an error. + /// + /// # Examples + /// + /// ``` + /// use tokio::io; + /// + /// # async fn dox() -> std::io::Result<()> { + /// let mut reader: &[u8] = b"hello"; + /// let mut writer: Vec<u8> = vec![]; + /// + /// io::copy(&mut reader, &mut writer).await?; + /// + /// assert_eq!(&b"hello"[..], &writer[..]); + /// # Ok(()) + /// # } + /// ``` + pub async fn copy<'a, R, W>(reader: &'a mut R, writer: &'a mut W) -> io::Result<u64> + where + R: AsyncRead + Unpin + ?Sized, + W: AsyncWrite + Unpin + ?Sized, + { + Copy { + reader, + writer, + buf: CopyBuffer::new() + }.await + } +} + +impl<R, W> Future for Copy<'_, R, W> +where + R: AsyncRead + Unpin + ?Sized, + W: AsyncWrite + Unpin + ?Sized, +{ + type Output = io::Result<u64>; + + fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<u64>> { + let me = &mut *self; + + me.buf + .poll_copy(cx, Pin::new(&mut *me.reader), Pin::new(&mut *me.writer)) + } +} diff --git a/third_party/rust/tokio/src/io/util/copy_bidirectional.rs b/third_party/rust/tokio/src/io/util/copy_bidirectional.rs new file mode 100644 index 0000000000..c93060b361 --- /dev/null +++ b/third_party/rust/tokio/src/io/util/copy_bidirectional.rs @@ -0,0 +1,120 @@ +use super::copy::CopyBuffer; + +use crate::io::{AsyncRead, AsyncWrite}; + +use std::future::Future; +use std::io; +use std::pin::Pin; +use std::task::{Context, Poll}; + +enum TransferState { + Running(CopyBuffer), + ShuttingDown(u64), + Done(u64), +} + +struct CopyBidirectional<'a, A: ?Sized, B: ?Sized> { + a: &'a mut A, + b: &'a mut B, + a_to_b: TransferState, + b_to_a: TransferState, +} + +fn transfer_one_direction<A, B>( + cx: &mut Context<'_>, + state: &mut TransferState, + r: &mut A, + w: &mut B, +) -> Poll<io::Result<u64>> +where + A: AsyncRead + AsyncWrite + Unpin + ?Sized, + B: AsyncRead + AsyncWrite + Unpin + ?Sized, +{ + let mut r = Pin::new(r); + let mut w = Pin::new(w); + + loop { + match state { + TransferState::Running(buf) => { + let count = ready!(buf.poll_copy(cx, r.as_mut(), w.as_mut()))?; + *state = TransferState::ShuttingDown(count); + } + TransferState::ShuttingDown(count) => { + ready!(w.as_mut().poll_shutdown(cx))?; + + *state = TransferState::Done(*count); + } + TransferState::Done(count) => return Poll::Ready(Ok(*count)), + } + } +} + +impl<'a, A, B> Future for CopyBidirectional<'a, A, B> +where + A: AsyncRead + AsyncWrite + Unpin + ?Sized, + B: AsyncRead + AsyncWrite + Unpin + ?Sized, +{ + type Output = io::Result<(u64, u64)>; + + fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> { + // Unpack self into mut refs to each field to avoid borrow check issues. + let CopyBidirectional { + a, + b, + a_to_b, + b_to_a, + } = &mut *self; + + let a_to_b = transfer_one_direction(cx, a_to_b, &mut *a, &mut *b)?; + let b_to_a = transfer_one_direction(cx, b_to_a, &mut *b, &mut *a)?; + + // It is not a problem if ready! returns early because transfer_one_direction for the + // other direction will keep returning TransferState::Done(count) in future calls to poll + let a_to_b = ready!(a_to_b); + let b_to_a = ready!(b_to_a); + + Poll::Ready(Ok((a_to_b, b_to_a))) + } +} + +/// Copies data in both directions between `a` and `b`. +/// +/// This function returns a future that will read from both streams, +/// writing any data read to the opposing stream. +/// This happens in both directions concurrently. +/// +/// If an EOF is observed on one stream, [`shutdown()`] will be invoked on +/// the other, and reading from that stream will stop. Copying of data in +/// the other direction will continue. +/// +/// The future will complete successfully once both directions of communication has been shut down. +/// A direction is shut down when the reader reports EOF, +/// at which point [`shutdown()`] is called on the corresponding writer. When finished, +/// it will return a tuple of the number of bytes copied from a to b +/// and the number of bytes copied from b to a, in that order. +/// +/// [`shutdown()`]: crate::io::AsyncWriteExt::shutdown +/// +/// # Errors +/// +/// The future will immediately return an error if any IO operation on `a` +/// or `b` returns an error. Some data read from either stream may be lost (not +/// written to the other stream) in this case. +/// +/// # Return value +/// +/// Returns a tuple of bytes copied `a` to `b` and bytes copied `b` to `a`. +#[cfg_attr(docsrs, doc(cfg(feature = "io-util")))] +pub async fn copy_bidirectional<A, B>(a: &mut A, b: &mut B) -> Result<(u64, u64), std::io::Error> +where + A: AsyncRead + AsyncWrite + Unpin + ?Sized, + B: AsyncRead + AsyncWrite + Unpin + ?Sized, +{ + CopyBidirectional { + a, + b, + a_to_b: TransferState::Running(CopyBuffer::new()), + b_to_a: TransferState::Running(CopyBuffer::new()), + } + .await +} diff --git a/third_party/rust/tokio/src/io/util/copy_buf.rs b/third_party/rust/tokio/src/io/util/copy_buf.rs new file mode 100644 index 0000000000..6831580b40 --- /dev/null +++ b/third_party/rust/tokio/src/io/util/copy_buf.rs @@ -0,0 +1,102 @@ +use crate::io::{AsyncBufRead, AsyncWrite}; +use std::future::Future; +use std::io; +use std::pin::Pin; +use std::task::{Context, Poll}; + +cfg_io_util! { + /// A future that asynchronously copies the entire contents of a reader into a + /// writer. + /// + /// This struct is generally created by calling [`copy_buf`][copy_buf]. Please + /// see the documentation of `copy_buf()` for more details. + /// + /// [copy_buf]: copy_buf() + #[derive(Debug)] + #[must_use = "futures do nothing unless you `.await` or poll them"] + struct CopyBuf<'a, R: ?Sized, W: ?Sized> { + reader: &'a mut R, + writer: &'a mut W, + amt: u64, + } + + /// Asynchronously copies the entire contents of a reader into a writer. + /// + /// This function returns a future that will continuously read data from + /// `reader` and then write it into `writer` in a streaming fashion until + /// `reader` returns EOF. + /// + /// On success, the total number of bytes that were copied from `reader` to + /// `writer` is returned. + /// + /// + /// # Errors + /// + /// The returned future will finish with an error will return an error + /// immediately if any call to `poll_fill_buf` or `poll_write` returns an + /// error. + /// + /// # Examples + /// + /// ``` + /// use tokio::io; + /// + /// # async fn dox() -> std::io::Result<()> { + /// let mut reader: &[u8] = b"hello"; + /// let mut writer: Vec<u8> = vec![]; + /// + /// io::copy_buf(&mut reader, &mut writer).await?; + /// + /// assert_eq!(b"hello", &writer[..]); + /// # Ok(()) + /// # } + /// ``` + pub async fn copy_buf<'a, R, W>(reader: &'a mut R, writer: &'a mut W) -> io::Result<u64> + where + R: AsyncBufRead + Unpin + ?Sized, + W: AsyncWrite + Unpin + ?Sized, + { + CopyBuf { + reader, + writer, + amt: 0, + }.await + } +} + +impl<R, W> Future for CopyBuf<'_, R, W> +where + R: AsyncBufRead + Unpin + ?Sized, + W: AsyncWrite + Unpin + ?Sized, +{ + type Output = io::Result<u64>; + + fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> { + loop { + let me = &mut *self; + let buffer = ready!(Pin::new(&mut *me.reader).poll_fill_buf(cx))?; + if buffer.is_empty() { + ready!(Pin::new(&mut self.writer).poll_flush(cx))?; + return Poll::Ready(Ok(self.amt)); + } + + let i = ready!(Pin::new(&mut *me.writer).poll_write(cx, buffer))?; + if i == 0 { + return Poll::Ready(Err(std::io::ErrorKind::WriteZero.into())); + } + self.amt += i as u64; + Pin::new(&mut *self.reader).consume(i); + } + } +} + +#[cfg(test)] +mod tests { + use super::*; + + #[test] + fn assert_unpin() { + use std::marker::PhantomPinned; + crate::is_unpin::<CopyBuf<'_, PhantomPinned, PhantomPinned>>(); + } +} diff --git a/third_party/rust/tokio/src/io/util/empty.rs b/third_party/rust/tokio/src/io/util/empty.rs new file mode 100644 index 0000000000..77db60e40b --- /dev/null +++ b/third_party/rust/tokio/src/io/util/empty.rs @@ -0,0 +1,100 @@ +use crate::io::{AsyncBufRead, AsyncRead, ReadBuf}; + +use std::fmt; +use std::io; +use std::pin::Pin; +use std::task::{Context, Poll}; + +cfg_io_util! { + /// An async reader which is always at EOF. + /// + /// This struct is generally created by calling [`empty`]. Please see + /// the documentation of [`empty()`][`empty`] for more details. + /// + /// This is an asynchronous version of [`std::io::empty`][std]. + /// + /// [`empty`]: fn@empty + /// [std]: std::io::empty + pub struct Empty { + _p: (), + } + + /// Creates a new empty async reader. + /// + /// All reads from the returned reader will return `Poll::Ready(Ok(0))`. + /// + /// This is an asynchronous version of [`std::io::empty`][std]. + /// + /// [std]: std::io::empty + /// + /// # Examples + /// + /// A slightly sad example of not reading anything into a buffer: + /// + /// ``` + /// use tokio::io::{self, AsyncReadExt}; + /// + /// #[tokio::main] + /// async fn main() { + /// let mut buffer = String::new(); + /// io::empty().read_to_string(&mut buffer).await.unwrap(); + /// assert!(buffer.is_empty()); + /// } + /// ``` + pub fn empty() -> Empty { + Empty { _p: () } + } +} + +impl AsyncRead for Empty { + #[inline] + fn poll_read( + self: Pin<&mut Self>, + cx: &mut Context<'_>, + _: &mut ReadBuf<'_>, + ) -> Poll<io::Result<()>> { + ready!(poll_proceed_and_make_progress(cx)); + Poll::Ready(Ok(())) + } +} + +impl AsyncBufRead for Empty { + #[inline] + fn poll_fill_buf(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<&[u8]>> { + ready!(poll_proceed_and_make_progress(cx)); + Poll::Ready(Ok(&[])) + } + + #[inline] + fn consume(self: Pin<&mut Self>, _: usize) {} +} + +impl fmt::Debug for Empty { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + f.pad("Empty { .. }") + } +} + +cfg_coop! { + fn poll_proceed_and_make_progress(cx: &mut Context<'_>) -> Poll<()> { + let coop = ready!(crate::coop::poll_proceed(cx)); + coop.made_progress(); + Poll::Ready(()) + } +} + +cfg_not_coop! { + fn poll_proceed_and_make_progress(_: &mut Context<'_>) -> Poll<()> { + Poll::Ready(()) + } +} + +#[cfg(test)] +mod tests { + use super::*; + + #[test] + fn assert_unpin() { + crate::is_unpin::<Empty>(); + } +} diff --git a/third_party/rust/tokio/src/io/util/fill_buf.rs b/third_party/rust/tokio/src/io/util/fill_buf.rs new file mode 100644 index 0000000000..bb07c766e2 --- /dev/null +++ b/third_party/rust/tokio/src/io/util/fill_buf.rs @@ -0,0 +1,59 @@ +use crate::io::AsyncBufRead; + +use pin_project_lite::pin_project; +use std::future::Future; +use std::io; +use std::marker::PhantomPinned; +use std::pin::Pin; +use std::task::{Context, Poll}; + +pin_project! { + /// Future for the [`fill_buf`](crate::io::AsyncBufReadExt::fill_buf) method. + #[derive(Debug)] + #[must_use = "futures do nothing unless you `.await` or poll them"] + pub struct FillBuf<'a, R: ?Sized> { + reader: Option<&'a mut R>, + #[pin] + _pin: PhantomPinned, + } +} + +pub(crate) fn fill_buf<R>(reader: &mut R) -> FillBuf<'_, R> +where + R: AsyncBufRead + ?Sized + Unpin, +{ + FillBuf { + reader: Some(reader), + _pin: PhantomPinned, + } +} + +impl<'a, R: AsyncBufRead + ?Sized + Unpin> Future for FillBuf<'a, R> { + type Output = io::Result<&'a [u8]>; + + fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> { + let me = self.project(); + + let reader = me.reader.take().expect("Polled after completion."); + match Pin::new(&mut *reader).poll_fill_buf(cx) { + Poll::Ready(Ok(slice)) => unsafe { + // Safety: This is necessary only due to a limitation in the + // borrow checker. Once Rust starts using the polonius borrow + // checker, this can be simplified. + // + // The safety of this transmute relies on the fact that the + // value of `reader` is `None` when we return in this branch. + // Otherwise the caller could poll us again after + // completion, and access the mutable reference while the + // returned immutable reference still exists. + let slice = std::mem::transmute::<&[u8], &'a [u8]>(slice); + Poll::Ready(Ok(slice)) + }, + Poll::Ready(Err(err)) => Poll::Ready(Err(err)), + Poll::Pending => { + *me.reader = Some(reader); + Poll::Pending + } + } + } +} diff --git a/third_party/rust/tokio/src/io/util/flush.rs b/third_party/rust/tokio/src/io/util/flush.rs new file mode 100644 index 0000000000..88d60b868d --- /dev/null +++ b/third_party/rust/tokio/src/io/util/flush.rs @@ -0,0 +1,46 @@ +use crate::io::AsyncWrite; + +use pin_project_lite::pin_project; +use std::future::Future; +use std::io; +use std::marker::PhantomPinned; +use std::pin::Pin; +use std::task::{Context, Poll}; + +pin_project! { + /// A future used to fully flush an I/O object. + /// + /// Created by the [`AsyncWriteExt::flush`][flush] function. + /// [flush]: crate::io::AsyncWriteExt::flush + #[derive(Debug)] + #[must_use = "futures do nothing unless you `.await` or poll them"] + pub struct Flush<'a, A: ?Sized> { + a: &'a mut A, + // Make this future `!Unpin` for compatibility with async trait methods. + #[pin] + _pin: PhantomPinned, + } +} + +/// Creates a future which will entirely flush an I/O object. +pub(super) fn flush<A>(a: &mut A) -> Flush<'_, A> +where + A: AsyncWrite + Unpin + ?Sized, +{ + Flush { + a, + _pin: PhantomPinned, + } +} + +impl<A> Future for Flush<'_, A> +where + A: AsyncWrite + Unpin + ?Sized, +{ + type Output = io::Result<()>; + + fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> { + let me = self.project(); + Pin::new(&mut *me.a).poll_flush(cx) + } +} diff --git a/third_party/rust/tokio/src/io/util/lines.rs b/third_party/rust/tokio/src/io/util/lines.rs new file mode 100644 index 0000000000..717f633f95 --- /dev/null +++ b/third_party/rust/tokio/src/io/util/lines.rs @@ -0,0 +1,145 @@ +use crate::io::util::read_line::read_line_internal; +use crate::io::AsyncBufRead; + +use pin_project_lite::pin_project; +use std::io; +use std::mem; +use std::pin::Pin; +use std::task::{Context, Poll}; + +pin_project! { + /// Reads lines from an [`AsyncBufRead`]. + /// + /// A `Lines` can be turned into a `Stream` with [`LinesStream`]. + /// + /// This type is usually created using the [`lines`] method. + /// + /// [`AsyncBufRead`]: crate::io::AsyncBufRead + /// [`LinesStream`]: https://docs.rs/tokio-stream/0.1/tokio_stream/wrappers/struct.LinesStream.html + /// [`lines`]: crate::io::AsyncBufReadExt::lines + #[derive(Debug)] + #[must_use = "streams do nothing unless polled"] + #[cfg_attr(docsrs, doc(cfg(feature = "io-util")))] + pub struct Lines<R> { + #[pin] + reader: R, + buf: String, + bytes: Vec<u8>, + read: usize, + } +} + +pub(crate) fn lines<R>(reader: R) -> Lines<R> +where + R: AsyncBufRead, +{ + Lines { + reader, + buf: String::new(), + bytes: Vec::new(), + read: 0, + } +} + +impl<R> Lines<R> +where + R: AsyncBufRead + Unpin, +{ + /// Returns the next line in the stream. + /// + /// # Cancel safety + /// + /// This method is cancellation safe. + /// + /// # Examples + /// + /// ``` + /// # use tokio::io::AsyncBufRead; + /// use tokio::io::AsyncBufReadExt; + /// + /// # async fn dox(my_buf_read: impl AsyncBufRead + Unpin) -> std::io::Result<()> { + /// let mut lines = my_buf_read.lines(); + /// + /// while let Some(line) = lines.next_line().await? { + /// println!("length = {}", line.len()) + /// } + /// # Ok(()) + /// # } + /// ``` + pub async fn next_line(&mut self) -> io::Result<Option<String>> { + use crate::future::poll_fn; + + poll_fn(|cx| Pin::new(&mut *self).poll_next_line(cx)).await + } + + /// Obtains a mutable reference to the underlying reader. + pub fn get_mut(&mut self) -> &mut R { + &mut self.reader + } + + /// Obtains a reference to the underlying reader. + pub fn get_ref(&mut self) -> &R { + &self.reader + } + + /// Unwraps this `Lines<R>`, returning the underlying reader. + /// + /// Note that any leftover data in the internal buffer is lost. + /// Therefore, a following read from the underlying reader may lead to data loss. + pub fn into_inner(self) -> R { + self.reader + } +} + +impl<R> Lines<R> +where + R: AsyncBufRead, +{ + /// Polls for the next line in the stream. + /// + /// This method returns: + /// + /// * `Poll::Pending` if the next line is not yet available. + /// * `Poll::Ready(Ok(Some(line)))` if the next line is available. + /// * `Poll::Ready(Ok(None))` if there are no more lines in this stream. + /// * `Poll::Ready(Err(err))` if an IO error occurred while reading the next line. + /// + /// When the method returns `Poll::Pending`, the `Waker` in the provided + /// `Context` is scheduled to receive a wakeup when more bytes become + /// available on the underlying IO resource. Note that on multiple calls to + /// `poll_next_line`, only the `Waker` from the `Context` passed to the most + /// recent call is scheduled to receive a wakeup. + pub fn poll_next_line( + self: Pin<&mut Self>, + cx: &mut Context<'_>, + ) -> Poll<io::Result<Option<String>>> { + let me = self.project(); + + let n = ready!(read_line_internal(me.reader, cx, me.buf, me.bytes, me.read))?; + debug_assert_eq!(*me.read, 0); + + if n == 0 && me.buf.is_empty() { + return Poll::Ready(Ok(None)); + } + + if me.buf.ends_with('\n') { + me.buf.pop(); + + if me.buf.ends_with('\r') { + me.buf.pop(); + } + } + + Poll::Ready(Ok(Some(mem::take(me.buf)))) + } +} + +#[cfg(test)] +mod tests { + use super::*; + + #[test] + fn assert_unpin() { + crate::is_unpin::<Lines<()>>(); + } +} diff --git a/third_party/rust/tokio/src/io/util/mem.rs b/third_party/rust/tokio/src/io/util/mem.rs new file mode 100644 index 0000000000..4019db56ff --- /dev/null +++ b/third_party/rust/tokio/src/io/util/mem.rs @@ -0,0 +1,295 @@ +//! In-process memory IO types. + +use crate::io::{AsyncRead, AsyncWrite, ReadBuf}; +use crate::loom::sync::Mutex; + +use bytes::{Buf, BytesMut}; +use std::{ + pin::Pin, + sync::Arc, + task::{self, Poll, Waker}, +}; + +/// A bidirectional pipe to read and write bytes in memory. +/// +/// A pair of `DuplexStream`s are created together, and they act as a "channel" +/// that can be used as in-memory IO types. Writing to one of the pairs will +/// allow that data to be read from the other, and vice versa. +/// +/// # Closing a `DuplexStream` +/// +/// If one end of the `DuplexStream` channel is dropped, any pending reads on +/// the other side will continue to read data until the buffer is drained, then +/// they will signal EOF by returning 0 bytes. Any writes to the other side, +/// including pending ones (that are waiting for free space in the buffer) will +/// return `Err(BrokenPipe)` immediately. +/// +/// # Example +/// +/// ``` +/// # async fn ex() -> std::io::Result<()> { +/// # use tokio::io::{AsyncReadExt, AsyncWriteExt}; +/// let (mut client, mut server) = tokio::io::duplex(64); +/// +/// client.write_all(b"ping").await?; +/// +/// let mut buf = [0u8; 4]; +/// server.read_exact(&mut buf).await?; +/// assert_eq!(&buf, b"ping"); +/// +/// server.write_all(b"pong").await?; +/// +/// client.read_exact(&mut buf).await?; +/// assert_eq!(&buf, b"pong"); +/// # Ok(()) +/// # } +/// ``` +#[derive(Debug)] +#[cfg_attr(docsrs, doc(cfg(feature = "io-util")))] +pub struct DuplexStream { + read: Arc<Mutex<Pipe>>, + write: Arc<Mutex<Pipe>>, +} + +/// A unidirectional IO over a piece of memory. +/// +/// Data can be written to the pipe, and reading will return that data. +#[derive(Debug)] +struct Pipe { + /// The buffer storing the bytes written, also read from. + /// + /// Using a `BytesMut` because it has efficient `Buf` and `BufMut` + /// functionality already. Additionally, it can try to copy data in the + /// same buffer if there read index has advanced far enough. + buffer: BytesMut, + /// Determines if the write side has been closed. + is_closed: bool, + /// The maximum amount of bytes that can be written before returning + /// `Poll::Pending`. + max_buf_size: usize, + /// If the `read` side has been polled and is pending, this is the waker + /// for that parked task. + read_waker: Option<Waker>, + /// If the `write` side has filled the `max_buf_size` and returned + /// `Poll::Pending`, this is the waker for that parked task. + write_waker: Option<Waker>, +} + +// ===== impl DuplexStream ===== + +/// Create a new pair of `DuplexStream`s that act like a pair of connected sockets. +/// +/// The `max_buf_size` argument is the maximum amount of bytes that can be +/// written to a side before the write returns `Poll::Pending`. +#[cfg_attr(docsrs, doc(cfg(feature = "io-util")))] +pub fn duplex(max_buf_size: usize) -> (DuplexStream, DuplexStream) { + let one = Arc::new(Mutex::new(Pipe::new(max_buf_size))); + let two = Arc::new(Mutex::new(Pipe::new(max_buf_size))); + + ( + DuplexStream { + read: one.clone(), + write: two.clone(), + }, + DuplexStream { + read: two, + write: one, + }, + ) +} + +impl AsyncRead for DuplexStream { + // Previous rustc required this `self` to be `mut`, even though newer + // versions recognize it isn't needed to call `lock()`. So for + // compatibility, we include the `mut` and `allow` the lint. + // + // See https://github.com/rust-lang/rust/issues/73592 + #[allow(unused_mut)] + fn poll_read( + mut self: Pin<&mut Self>, + cx: &mut task::Context<'_>, + buf: &mut ReadBuf<'_>, + ) -> Poll<std::io::Result<()>> { + Pin::new(&mut *self.read.lock()).poll_read(cx, buf) + } +} + +impl AsyncWrite for DuplexStream { + #[allow(unused_mut)] + fn poll_write( + mut self: Pin<&mut Self>, + cx: &mut task::Context<'_>, + buf: &[u8], + ) -> Poll<std::io::Result<usize>> { + Pin::new(&mut *self.write.lock()).poll_write(cx, buf) + } + + #[allow(unused_mut)] + fn poll_flush( + mut self: Pin<&mut Self>, + cx: &mut task::Context<'_>, + ) -> Poll<std::io::Result<()>> { + Pin::new(&mut *self.write.lock()).poll_flush(cx) + } + + #[allow(unused_mut)] + fn poll_shutdown( + mut self: Pin<&mut Self>, + cx: &mut task::Context<'_>, + ) -> Poll<std::io::Result<()>> { + Pin::new(&mut *self.write.lock()).poll_shutdown(cx) + } +} + +impl Drop for DuplexStream { + fn drop(&mut self) { + // notify the other side of the closure + self.write.lock().close_write(); + self.read.lock().close_read(); + } +} + +// ===== impl Pipe ===== + +impl Pipe { + fn new(max_buf_size: usize) -> Self { + Pipe { + buffer: BytesMut::new(), + is_closed: false, + max_buf_size, + read_waker: None, + write_waker: None, + } + } + + fn close_write(&mut self) { + self.is_closed = true; + // needs to notify any readers that no more data will come + if let Some(waker) = self.read_waker.take() { + waker.wake(); + } + } + + fn close_read(&mut self) { + self.is_closed = true; + // needs to notify any writers that they have to abort + if let Some(waker) = self.write_waker.take() { + waker.wake(); + } + } + + fn poll_read_internal( + mut self: Pin<&mut Self>, + cx: &mut task::Context<'_>, + buf: &mut ReadBuf<'_>, + ) -> Poll<std::io::Result<()>> { + if self.buffer.has_remaining() { + let max = self.buffer.remaining().min(buf.remaining()); + buf.put_slice(&self.buffer[..max]); + self.buffer.advance(max); + if max > 0 { + // The passed `buf` might have been empty, don't wake up if + // no bytes have been moved. + if let Some(waker) = self.write_waker.take() { + waker.wake(); + } + } + Poll::Ready(Ok(())) + } else if self.is_closed { + Poll::Ready(Ok(())) + } else { + self.read_waker = Some(cx.waker().clone()); + Poll::Pending + } + } + + fn poll_write_internal( + mut self: Pin<&mut Self>, + cx: &mut task::Context<'_>, + buf: &[u8], + ) -> Poll<std::io::Result<usize>> { + if self.is_closed { + return Poll::Ready(Err(std::io::ErrorKind::BrokenPipe.into())); + } + let avail = self.max_buf_size - self.buffer.len(); + if avail == 0 { + self.write_waker = Some(cx.waker().clone()); + return Poll::Pending; + } + + let len = buf.len().min(avail); + self.buffer.extend_from_slice(&buf[..len]); + if let Some(waker) = self.read_waker.take() { + waker.wake(); + } + Poll::Ready(Ok(len)) + } +} + +impl AsyncRead for Pipe { + cfg_coop! { + fn poll_read( + self: Pin<&mut Self>, + cx: &mut task::Context<'_>, + buf: &mut ReadBuf<'_>, + ) -> Poll<std::io::Result<()>> { + let coop = ready!(crate::coop::poll_proceed(cx)); + + let ret = self.poll_read_internal(cx, buf); + if ret.is_ready() { + coop.made_progress(); + } + ret + } + } + + cfg_not_coop! { + fn poll_read( + self: Pin<&mut Self>, + cx: &mut task::Context<'_>, + buf: &mut ReadBuf<'_>, + ) -> Poll<std::io::Result<()>> { + self.poll_read_internal(cx, buf) + } + } +} + +impl AsyncWrite for Pipe { + cfg_coop! { + fn poll_write( + self: Pin<&mut Self>, + cx: &mut task::Context<'_>, + buf: &[u8], + ) -> Poll<std::io::Result<usize>> { + let coop = ready!(crate::coop::poll_proceed(cx)); + + let ret = self.poll_write_internal(cx, buf); + if ret.is_ready() { + coop.made_progress(); + } + ret + } + } + + cfg_not_coop! { + fn poll_write( + self: Pin<&mut Self>, + cx: &mut task::Context<'_>, + buf: &[u8], + ) -> Poll<std::io::Result<usize>> { + self.poll_write_internal(cx, buf) + } + } + + fn poll_flush(self: Pin<&mut Self>, _: &mut task::Context<'_>) -> Poll<std::io::Result<()>> { + Poll::Ready(Ok(())) + } + + fn poll_shutdown( + mut self: Pin<&mut Self>, + _: &mut task::Context<'_>, + ) -> Poll<std::io::Result<()>> { + self.close_write(); + Poll::Ready(Ok(())) + } +} diff --git a/third_party/rust/tokio/src/io/util/mod.rs b/third_party/rust/tokio/src/io/util/mod.rs new file mode 100644 index 0000000000..21199d0be8 --- /dev/null +++ b/third_party/rust/tokio/src/io/util/mod.rs @@ -0,0 +1,97 @@ +#![allow(unreachable_pub)] // https://github.com/rust-lang/rust/issues/57411 + +cfg_io_util! { + mod async_buf_read_ext; + pub use async_buf_read_ext::AsyncBufReadExt; + + mod async_read_ext; + pub use async_read_ext::AsyncReadExt; + + mod async_seek_ext; + pub use async_seek_ext::AsyncSeekExt; + + mod async_write_ext; + pub use async_write_ext::AsyncWriteExt; + + mod buf_reader; + pub use buf_reader::BufReader; + + mod buf_stream; + pub use buf_stream::BufStream; + + mod buf_writer; + pub use buf_writer::BufWriter; + + mod chain; + + mod copy; + pub use copy::copy; + + mod copy_bidirectional; + pub use copy_bidirectional::copy_bidirectional; + + mod copy_buf; + pub use copy_buf::copy_buf; + + mod empty; + pub use empty::{empty, Empty}; + + mod flush; + + mod lines; + pub use lines::Lines; + + mod mem; + pub use mem::{duplex, DuplexStream}; + + mod read; + mod read_buf; + mod read_exact; + mod read_int; + mod read_line; + mod fill_buf; + + mod read_to_end; + mod vec_with_initialized; + cfg_process! { + pub(crate) use read_to_end::read_to_end; + } + + mod read_to_string; + mod read_until; + + mod repeat; + pub use repeat::{repeat, Repeat}; + + mod shutdown; + + mod sink; + pub use sink::{sink, Sink}; + + mod split; + pub use split::Split; + + mod take; + pub use take::Take; + + mod write; + mod write_vectored; + mod write_all; + mod write_buf; + mod write_all_buf; + mod write_int; + + + // used by `BufReader` and `BufWriter` + // https://github.com/rust-lang/rust/blob/master/library/std/src/sys_common/io.rs#L1 + const DEFAULT_BUF_SIZE: usize = 8 * 1024; +} + +cfg_not_io_util! { + cfg_process! { + mod vec_with_initialized; + mod read_to_end; + // Used by process + pub(crate) use read_to_end::read_to_end; + } +} diff --git a/third_party/rust/tokio/src/io/util/read.rs b/third_party/rust/tokio/src/io/util/read.rs new file mode 100644 index 0000000000..edc9d5a9e6 --- /dev/null +++ b/third_party/rust/tokio/src/io/util/read.rs @@ -0,0 +1,55 @@ +use crate::io::{AsyncRead, ReadBuf}; + +use pin_project_lite::pin_project; +use std::future::Future; +use std::io; +use std::marker::PhantomPinned; +use std::marker::Unpin; +use std::pin::Pin; +use std::task::{Context, Poll}; + +/// Tries to read some bytes directly into the given `buf` in asynchronous +/// manner, returning a future type. +/// +/// The returned future will resolve to both the I/O stream and the buffer +/// as well as the number of bytes read once the read operation is completed. +pub(crate) fn read<'a, R>(reader: &'a mut R, buf: &'a mut [u8]) -> Read<'a, R> +where + R: AsyncRead + Unpin + ?Sized, +{ + Read { + reader, + buf, + _pin: PhantomPinned, + } +} + +pin_project! { + /// A future which can be used to easily read available number of bytes to fill + /// a buffer. + /// + /// Created by the [`read`] function. + #[derive(Debug)] + #[must_use = "futures do nothing unless you `.await` or poll them"] + pub struct Read<'a, R: ?Sized> { + reader: &'a mut R, + buf: &'a mut [u8], + // Make this future `!Unpin` for compatibility with async trait methods. + #[pin] + _pin: PhantomPinned, + } +} + +impl<R> Future for Read<'_, R> +where + R: AsyncRead + Unpin + ?Sized, +{ + type Output = io::Result<usize>; + + fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<usize>> { + let me = self.project(); + let mut buf = ReadBuf::new(*me.buf); + ready!(Pin::new(me.reader).poll_read(cx, &mut buf))?; + Poll::Ready(Ok(buf.filled().len())) + } +} diff --git a/third_party/rust/tokio/src/io/util/read_buf.rs b/third_party/rust/tokio/src/io/util/read_buf.rs new file mode 100644 index 0000000000..8ec57c0d6f --- /dev/null +++ b/third_party/rust/tokio/src/io/util/read_buf.rs @@ -0,0 +1,72 @@ +use crate::io::AsyncRead; + +use bytes::BufMut; +use pin_project_lite::pin_project; +use std::future::Future; +use std::io; +use std::marker::PhantomPinned; +use std::pin::Pin; +use std::task::{Context, Poll}; + +pub(crate) fn read_buf<'a, R, B>(reader: &'a mut R, buf: &'a mut B) -> ReadBuf<'a, R, B> +where + R: AsyncRead + Unpin, + B: BufMut, +{ + ReadBuf { + reader, + buf, + _pin: PhantomPinned, + } +} + +pin_project! { + /// Future returned by [`read_buf`](crate::io::AsyncReadExt::read_buf). + #[derive(Debug)] + #[must_use = "futures do nothing unless you `.await` or poll them"] + pub struct ReadBuf<'a, R, B> { + reader: &'a mut R, + buf: &'a mut B, + #[pin] + _pin: PhantomPinned, + } +} + +impl<R, B> Future for ReadBuf<'_, R, B> +where + R: AsyncRead + Unpin, + B: BufMut, +{ + type Output = io::Result<usize>; + + fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<usize>> { + use crate::io::ReadBuf; + use std::mem::MaybeUninit; + + let me = self.project(); + + if !me.buf.has_remaining_mut() { + return Poll::Ready(Ok(0)); + } + + let n = { + let dst = me.buf.chunk_mut(); + let dst = unsafe { &mut *(dst as *mut _ as *mut [MaybeUninit<u8>]) }; + let mut buf = ReadBuf::uninit(dst); + let ptr = buf.filled().as_ptr(); + ready!(Pin::new(me.reader).poll_read(cx, &mut buf)?); + + // Ensure the pointer does not change from under us + assert_eq!(ptr, buf.filled().as_ptr()); + buf.filled().len() + }; + + // Safety: This is guaranteed to be the number of initialized (and read) + // bytes due to the invariants provided by `ReadBuf::filled`. + unsafe { + me.buf.advance_mut(n); + } + + Poll::Ready(Ok(n)) + } +} diff --git a/third_party/rust/tokio/src/io/util/read_exact.rs b/third_party/rust/tokio/src/io/util/read_exact.rs new file mode 100644 index 0000000000..dbdd58bae9 --- /dev/null +++ b/third_party/rust/tokio/src/io/util/read_exact.rs @@ -0,0 +1,69 @@ +use crate::io::{AsyncRead, ReadBuf}; + +use pin_project_lite::pin_project; +use std::future::Future; +use std::io; +use std::marker::PhantomPinned; +use std::marker::Unpin; +use std::pin::Pin; +use std::task::{Context, Poll}; + +/// A future which can be used to easily read exactly enough bytes to fill +/// a buffer. +/// +/// Created by the [`AsyncReadExt::read_exact`][read_exact]. +/// [read_exact]: [crate::io::AsyncReadExt::read_exact] +pub(crate) fn read_exact<'a, A>(reader: &'a mut A, buf: &'a mut [u8]) -> ReadExact<'a, A> +where + A: AsyncRead + Unpin + ?Sized, +{ + ReadExact { + reader, + buf: ReadBuf::new(buf), + _pin: PhantomPinned, + } +} + +pin_project! { + /// Creates a future which will read exactly enough bytes to fill `buf`, + /// returning an error if EOF is hit sooner. + /// + /// On success the number of bytes is returned + #[derive(Debug)] + #[must_use = "futures do nothing unless you `.await` or poll them"] + pub struct ReadExact<'a, A: ?Sized> { + reader: &'a mut A, + buf: ReadBuf<'a>, + // Make this future `!Unpin` for compatibility with async trait methods. + #[pin] + _pin: PhantomPinned, + } +} + +fn eof() -> io::Error { + io::Error::new(io::ErrorKind::UnexpectedEof, "early eof") +} + +impl<A> Future for ReadExact<'_, A> +where + A: AsyncRead + Unpin + ?Sized, +{ + type Output = io::Result<usize>; + + fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<usize>> { + let me = self.project(); + + loop { + // if our buffer is empty, then we need to read some data to continue. + let rem = me.buf.remaining(); + if rem != 0 { + ready!(Pin::new(&mut *me.reader).poll_read(cx, me.buf))?; + if me.buf.remaining() == rem { + return Err(eof()).into(); + } + } else { + return Poll::Ready(Ok(me.buf.capacity())); + } + } + } +} diff --git a/third_party/rust/tokio/src/io/util/read_int.rs b/third_party/rust/tokio/src/io/util/read_int.rs new file mode 100644 index 0000000000..164dcf5963 --- /dev/null +++ b/third_party/rust/tokio/src/io/util/read_int.rs @@ -0,0 +1,159 @@ +use crate::io::{AsyncRead, ReadBuf}; + +use bytes::Buf; +use pin_project_lite::pin_project; +use std::future::Future; +use std::io; +use std::io::ErrorKind::UnexpectedEof; +use std::marker::PhantomPinned; +use std::mem::size_of; +use std::pin::Pin; +use std::task::{Context, Poll}; + +macro_rules! reader { + ($name:ident, $ty:ty, $reader:ident) => { + reader!($name, $ty, $reader, size_of::<$ty>()); + }; + ($name:ident, $ty:ty, $reader:ident, $bytes:expr) => { + pin_project! { + #[doc(hidden)] + #[must_use = "futures do nothing unless you `.await` or poll them"] + pub struct $name<R> { + #[pin] + src: R, + buf: [u8; $bytes], + read: u8, + // Make this future `!Unpin` for compatibility with async trait methods. + #[pin] + _pin: PhantomPinned, + } + } + + impl<R> $name<R> { + pub(crate) fn new(src: R) -> Self { + $name { + src, + buf: [0; $bytes], + read: 0, + _pin: PhantomPinned, + } + } + } + + impl<R> Future for $name<R> + where + R: AsyncRead, + { + type Output = io::Result<$ty>; + + fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> { + let mut me = self.project(); + + if *me.read == $bytes as u8 { + return Poll::Ready(Ok(Buf::$reader(&mut &me.buf[..]))); + } + + while *me.read < $bytes as u8 { + let mut buf = ReadBuf::new(&mut me.buf[*me.read as usize..]); + + *me.read += match me.src.as_mut().poll_read(cx, &mut buf) { + Poll::Pending => return Poll::Pending, + Poll::Ready(Err(e)) => return Poll::Ready(Err(e.into())), + Poll::Ready(Ok(())) => { + let n = buf.filled().len(); + if n == 0 { + return Poll::Ready(Err(UnexpectedEof.into())); + } + + n as u8 + } + }; + } + + let num = Buf::$reader(&mut &me.buf[..]); + + Poll::Ready(Ok(num)) + } + } + }; +} + +macro_rules! reader8 { + ($name:ident, $ty:ty) => { + pin_project! { + /// Future returned from `read_u8` + #[doc(hidden)] + #[must_use = "futures do nothing unless you `.await` or poll them"] + pub struct $name<R> { + #[pin] + reader: R, + // Make this future `!Unpin` for compatibility with async trait methods. + #[pin] + _pin: PhantomPinned, + } + } + + impl<R> $name<R> { + pub(crate) fn new(reader: R) -> $name<R> { + $name { + reader, + _pin: PhantomPinned, + } + } + } + + impl<R> Future for $name<R> + where + R: AsyncRead, + { + type Output = io::Result<$ty>; + + fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> { + let me = self.project(); + + let mut buf = [0; 1]; + let mut buf = ReadBuf::new(&mut buf); + match me.reader.poll_read(cx, &mut buf) { + Poll::Pending => Poll::Pending, + Poll::Ready(Err(e)) => Poll::Ready(Err(e.into())), + Poll::Ready(Ok(())) => { + if buf.filled().len() == 0 { + return Poll::Ready(Err(UnexpectedEof.into())); + } + + Poll::Ready(Ok(buf.filled()[0] as $ty)) + } + } + } + } + }; +} + +reader8!(ReadU8, u8); +reader8!(ReadI8, i8); + +reader!(ReadU16, u16, get_u16); +reader!(ReadU32, u32, get_u32); +reader!(ReadU64, u64, get_u64); +reader!(ReadU128, u128, get_u128); + +reader!(ReadI16, i16, get_i16); +reader!(ReadI32, i32, get_i32); +reader!(ReadI64, i64, get_i64); +reader!(ReadI128, i128, get_i128); + +reader!(ReadF32, f32, get_f32); +reader!(ReadF64, f64, get_f64); + +reader!(ReadU16Le, u16, get_u16_le); +reader!(ReadU32Le, u32, get_u32_le); +reader!(ReadU64Le, u64, get_u64_le); +reader!(ReadU128Le, u128, get_u128_le); + +reader!(ReadI16Le, i16, get_i16_le); +reader!(ReadI32Le, i32, get_i32_le); +reader!(ReadI64Le, i64, get_i64_le); +reader!(ReadI128Le, i128, get_i128_le); + +reader!(ReadF32Le, f32, get_f32_le); +reader!(ReadF64Le, f64, get_f64_le); diff --git a/third_party/rust/tokio/src/io/util/read_line.rs b/third_party/rust/tokio/src/io/util/read_line.rs new file mode 100644 index 0000000000..e641f51532 --- /dev/null +++ b/third_party/rust/tokio/src/io/util/read_line.rs @@ -0,0 +1,119 @@ +use crate::io::util::read_until::read_until_internal; +use crate::io::AsyncBufRead; + +use pin_project_lite::pin_project; +use std::future::Future; +use std::io; +use std::marker::PhantomPinned; +use std::mem; +use std::pin::Pin; +use std::string::FromUtf8Error; +use std::task::{Context, Poll}; + +pin_project! { + /// Future for the [`read_line`](crate::io::AsyncBufReadExt::read_line) method. + #[derive(Debug)] + #[must_use = "futures do nothing unless you `.await` or poll them"] + pub struct ReadLine<'a, R: ?Sized> { + reader: &'a mut R, + // This is the buffer we were provided. It will be replaced with an empty string + // while reading to postpone utf-8 handling until after reading. + output: &'a mut String, + // The actual allocation of the string is moved into this vector instead. + buf: Vec<u8>, + // The number of bytes appended to buf. This can be less than buf.len() if + // the buffer was not empty when the operation was started. + read: usize, + // Make this future `!Unpin` for compatibility with async trait methods. + #[pin] + _pin: PhantomPinned, + } +} + +pub(crate) fn read_line<'a, R>(reader: &'a mut R, string: &'a mut String) -> ReadLine<'a, R> +where + R: AsyncBufRead + ?Sized + Unpin, +{ + ReadLine { + reader, + buf: mem::take(string).into_bytes(), + output: string, + read: 0, + _pin: PhantomPinned, + } +} + +fn put_back_original_data(output: &mut String, mut vector: Vec<u8>, num_bytes_read: usize) { + let original_len = vector.len() - num_bytes_read; + vector.truncate(original_len); + *output = String::from_utf8(vector).expect("The original data must be valid utf-8."); +} + +/// This handles the various failure cases and puts the string back into `output`. +/// +/// The `truncate_on_io_error` bool is necessary because `read_to_string` and `read_line` +/// disagree on what should happen when an IO error occurs. +pub(super) fn finish_string_read( + io_res: io::Result<usize>, + utf8_res: Result<String, FromUtf8Error>, + read: usize, + output: &mut String, + truncate_on_io_error: bool, +) -> Poll<io::Result<usize>> { + match (io_res, utf8_res) { + (Ok(num_bytes), Ok(string)) => { + debug_assert_eq!(read, 0); + *output = string; + Poll::Ready(Ok(num_bytes)) + } + (Err(io_err), Ok(string)) => { + *output = string; + if truncate_on_io_error { + let original_len = output.len() - read; + output.truncate(original_len); + } + Poll::Ready(Err(io_err)) + } + (Ok(num_bytes), Err(utf8_err)) => { + debug_assert_eq!(read, 0); + put_back_original_data(output, utf8_err.into_bytes(), num_bytes); + + Poll::Ready(Err(io::Error::new( + io::ErrorKind::InvalidData, + "stream did not contain valid UTF-8", + ))) + } + (Err(io_err), Err(utf8_err)) => { + put_back_original_data(output, utf8_err.into_bytes(), read); + + Poll::Ready(Err(io_err)) + } + } +} + +pub(super) fn read_line_internal<R: AsyncBufRead + ?Sized>( + reader: Pin<&mut R>, + cx: &mut Context<'_>, + output: &mut String, + buf: &mut Vec<u8>, + read: &mut usize, +) -> Poll<io::Result<usize>> { + let io_res = ready!(read_until_internal(reader, cx, b'\n', buf, read)); + let utf8_res = String::from_utf8(mem::take(buf)); + + // At this point both buf and output are empty. The allocation is in utf8_res. + + debug_assert!(buf.is_empty()); + debug_assert!(output.is_empty()); + finish_string_read(io_res, utf8_res, *read, output, false) +} + +impl<R: AsyncBufRead + ?Sized + Unpin> Future for ReadLine<'_, R> { + type Output = io::Result<usize>; + + fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> { + let me = self.project(); + + read_line_internal(Pin::new(*me.reader), cx, me.output, me.buf, me.read) + } +} diff --git a/third_party/rust/tokio/src/io/util/read_to_end.rs b/third_party/rust/tokio/src/io/util/read_to_end.rs new file mode 100644 index 0000000000..f4a564d7dd --- /dev/null +++ b/third_party/rust/tokio/src/io/util/read_to_end.rs @@ -0,0 +1,112 @@ +use crate::io::util::vec_with_initialized::{into_read_buf_parts, VecU8, VecWithInitialized}; +use crate::io::AsyncRead; + +use pin_project_lite::pin_project; +use std::future::Future; +use std::io; +use std::marker::PhantomPinned; +use std::mem; +use std::pin::Pin; +use std::task::{Context, Poll}; + +pin_project! { + #[derive(Debug)] + #[must_use = "futures do nothing unless you `.await` or poll them"] + pub struct ReadToEnd<'a, R: ?Sized> { + reader: &'a mut R, + buf: VecWithInitialized<&'a mut Vec<u8>>, + // The number of bytes appended to buf. This can be less than buf.len() if + // the buffer was not empty when the operation was started. + read: usize, + // Make this future `!Unpin` for compatibility with async trait methods. + #[pin] + _pin: PhantomPinned, + } +} + +pub(crate) fn read_to_end<'a, R>(reader: &'a mut R, buffer: &'a mut Vec<u8>) -> ReadToEnd<'a, R> +where + R: AsyncRead + Unpin + ?Sized, +{ + ReadToEnd { + reader, + buf: VecWithInitialized::new(buffer), + read: 0, + _pin: PhantomPinned, + } +} + +pub(super) fn read_to_end_internal<V: VecU8, R: AsyncRead + ?Sized>( + buf: &mut VecWithInitialized<V>, + mut reader: Pin<&mut R>, + num_read: &mut usize, + cx: &mut Context<'_>, +) -> Poll<io::Result<usize>> { + loop { + let ret = ready!(poll_read_to_end(buf, reader.as_mut(), cx)); + match ret { + Err(err) => return Poll::Ready(Err(err)), + Ok(0) => return Poll::Ready(Ok(mem::replace(num_read, 0))), + Ok(num) => { + *num_read += num; + } + } + } +} + +/// Tries to read from the provided AsyncRead. +/// +/// The length of the buffer is increased by the number of bytes read. +fn poll_read_to_end<V: VecU8, R: AsyncRead + ?Sized>( + buf: &mut VecWithInitialized<V>, + read: Pin<&mut R>, + cx: &mut Context<'_>, +) -> Poll<io::Result<usize>> { + // This uses an adaptive system to extend the vector when it fills. We want to + // avoid paying to allocate and zero a huge chunk of memory if the reader only + // has 4 bytes while still making large reads if the reader does have a ton + // of data to return. Simply tacking on an extra DEFAULT_BUF_SIZE space every + // time is 4,500 times (!) slower than this if the reader has a very small + // amount of data to return. + buf.reserve(32); + + // Get a ReadBuf into the vector. + let mut read_buf = buf.get_read_buf(); + + let filled_before = read_buf.filled().len(); + let poll_result = read.poll_read(cx, &mut read_buf); + let filled_after = read_buf.filled().len(); + let n = filled_after - filled_before; + + // Update the length of the vector using the result of poll_read. + let read_buf_parts = into_read_buf_parts(read_buf); + buf.apply_read_buf(read_buf_parts); + + match poll_result { + Poll::Pending => { + // In this case, nothing should have been read. However we still + // update the vector in case the poll_read call initialized parts of + // the vector's unused capacity. + debug_assert_eq!(filled_before, filled_after); + Poll::Pending + } + Poll::Ready(Err(err)) => { + debug_assert_eq!(filled_before, filled_after); + Poll::Ready(Err(err)) + } + Poll::Ready(Ok(())) => Poll::Ready(Ok(n)), + } +} + +impl<A> Future for ReadToEnd<'_, A> +where + A: AsyncRead + ?Sized + Unpin, +{ + type Output = io::Result<usize>; + + fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> { + let me = self.project(); + + read_to_end_internal(me.buf, Pin::new(*me.reader), me.read, cx) + } +} diff --git a/third_party/rust/tokio/src/io/util/read_to_string.rs b/third_party/rust/tokio/src/io/util/read_to_string.rs new file mode 100644 index 0000000000..b3d82a26ba --- /dev/null +++ b/third_party/rust/tokio/src/io/util/read_to_string.rs @@ -0,0 +1,78 @@ +use crate::io::util::read_line::finish_string_read; +use crate::io::util::read_to_end::read_to_end_internal; +use crate::io::util::vec_with_initialized::VecWithInitialized; +use crate::io::AsyncRead; + +use pin_project_lite::pin_project; +use std::future::Future; +use std::marker::PhantomPinned; +use std::pin::Pin; +use std::task::{Context, Poll}; +use std::{io, mem}; + +pin_project! { + /// Future for the [`read_to_string`](super::AsyncReadExt::read_to_string) method. + #[derive(Debug)] + #[must_use = "futures do nothing unless you `.await` or poll them"] + pub struct ReadToString<'a, R: ?Sized> { + reader: &'a mut R, + // This is the buffer we were provided. It will be replaced with an empty string + // while reading to postpone utf-8 handling until after reading. + output: &'a mut String, + // The actual allocation of the string is moved into this vector instead. + buf: VecWithInitialized<Vec<u8>>, + // The number of bytes appended to buf. This can be less than buf.len() if + // the buffer was not empty when the operation was started. + read: usize, + // Make this future `!Unpin` for compatibility with async trait methods. + #[pin] + _pin: PhantomPinned, + } +} + +pub(crate) fn read_to_string<'a, R>( + reader: &'a mut R, + string: &'a mut String, +) -> ReadToString<'a, R> +where + R: AsyncRead + ?Sized + Unpin, +{ + let buf = mem::take(string).into_bytes(); + ReadToString { + reader, + buf: VecWithInitialized::new(buf), + output: string, + read: 0, + _pin: PhantomPinned, + } +} + +fn read_to_string_internal<R: AsyncRead + ?Sized>( + reader: Pin<&mut R>, + output: &mut String, + buf: &mut VecWithInitialized<Vec<u8>>, + read: &mut usize, + cx: &mut Context<'_>, +) -> Poll<io::Result<usize>> { + let io_res = ready!(read_to_end_internal(buf, reader, read, cx)); + let utf8_res = String::from_utf8(buf.take()); + + // At this point both buf and output are empty. The allocation is in utf8_res. + + debug_assert!(buf.is_empty()); + debug_assert!(output.is_empty()); + finish_string_read(io_res, utf8_res, *read, output, true) +} + +impl<A> Future for ReadToString<'_, A> +where + A: AsyncRead + ?Sized + Unpin, +{ + type Output = io::Result<usize>; + + fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> { + let me = self.project(); + + read_to_string_internal(Pin::new(*me.reader), me.output, me.buf, me.read, cx) + } +} diff --git a/third_party/rust/tokio/src/io/util/read_until.rs b/third_party/rust/tokio/src/io/util/read_until.rs new file mode 100644 index 0000000000..90a0e8a18d --- /dev/null +++ b/third_party/rust/tokio/src/io/util/read_until.rs @@ -0,0 +1,79 @@ +use crate::io::AsyncBufRead; + +use pin_project_lite::pin_project; +use std::future::Future; +use std::io; +use std::marker::PhantomPinned; +use std::mem; +use std::pin::Pin; +use std::task::{Context, Poll}; + +pin_project! { + /// Future for the [`read_until`](crate::io::AsyncBufReadExt::read_until) method. + /// The delimiter is included in the resulting vector. + #[derive(Debug)] + #[must_use = "futures do nothing unless you `.await` or poll them"] + pub struct ReadUntil<'a, R: ?Sized> { + reader: &'a mut R, + delimiter: u8, + buf: &'a mut Vec<u8>, + // The number of bytes appended to buf. This can be less than buf.len() if + // the buffer was not empty when the operation was started. + read: usize, + // Make this future `!Unpin` for compatibility with async trait methods. + #[pin] + _pin: PhantomPinned, + } +} + +pub(crate) fn read_until<'a, R>( + reader: &'a mut R, + delimiter: u8, + buf: &'a mut Vec<u8>, +) -> ReadUntil<'a, R> +where + R: AsyncBufRead + ?Sized + Unpin, +{ + ReadUntil { + reader, + delimiter, + buf, + read: 0, + _pin: PhantomPinned, + } +} + +pub(super) fn read_until_internal<R: AsyncBufRead + ?Sized>( + mut reader: Pin<&mut R>, + cx: &mut Context<'_>, + delimiter: u8, + buf: &mut Vec<u8>, + read: &mut usize, +) -> Poll<io::Result<usize>> { + loop { + let (done, used) = { + let available = ready!(reader.as_mut().poll_fill_buf(cx))?; + if let Some(i) = memchr::memchr(delimiter, available) { + buf.extend_from_slice(&available[..=i]); + (true, i + 1) + } else { + buf.extend_from_slice(available); + (false, available.len()) + } + }; + reader.as_mut().consume(used); + *read += used; + if done || used == 0 { + return Poll::Ready(Ok(mem::replace(read, 0))); + } + } +} + +impl<R: AsyncBufRead + ?Sized + Unpin> Future for ReadUntil<'_, R> { + type Output = io::Result<usize>; + + fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> { + let me = self.project(); + read_until_internal(Pin::new(*me.reader), cx, *me.delimiter, me.buf, me.read) + } +} diff --git a/third_party/rust/tokio/src/io/util/repeat.rs b/third_party/rust/tokio/src/io/util/repeat.rs new file mode 100644 index 0000000000..1142765df5 --- /dev/null +++ b/third_party/rust/tokio/src/io/util/repeat.rs @@ -0,0 +1,72 @@ +use crate::io::{AsyncRead, ReadBuf}; + +use std::io; +use std::pin::Pin; +use std::task::{Context, Poll}; + +cfg_io_util! { + /// An async reader which yields one byte over and over and over and over and + /// over and... + /// + /// This struct is generally created by calling [`repeat`][repeat]. Please + /// see the documentation of `repeat()` for more details. + /// + /// This is an asynchronous version of [`std::io::Repeat`][std]. + /// + /// [repeat]: fn@repeat + /// [std]: std::io::Repeat + #[derive(Debug)] + pub struct Repeat { + byte: u8, + } + + /// Creates an instance of an async reader that infinitely repeats one byte. + /// + /// All reads from this reader will succeed by filling the specified buffer with + /// the given byte. + /// + /// This is an asynchronous version of [`std::io::repeat`][std]. + /// + /// [std]: std::io::repeat + /// + /// # Examples + /// + /// ``` + /// use tokio::io::{self, AsyncReadExt}; + /// + /// #[tokio::main] + /// async fn main() { + /// let mut buffer = [0; 3]; + /// io::repeat(0b101).read_exact(&mut buffer).await.unwrap(); + /// assert_eq!(buffer, [0b101, 0b101, 0b101]); + /// } + /// ``` + pub fn repeat(byte: u8) -> Repeat { + Repeat { byte } + } +} + +impl AsyncRead for Repeat { + #[inline] + fn poll_read( + self: Pin<&mut Self>, + _: &mut Context<'_>, + buf: &mut ReadBuf<'_>, + ) -> Poll<io::Result<()>> { + // TODO: could be faster, but should we unsafe it? + while buf.remaining() != 0 { + buf.put_slice(&[self.byte]); + } + Poll::Ready(Ok(())) + } +} + +#[cfg(test)] +mod tests { + use super::*; + + #[test] + fn assert_unpin() { + crate::is_unpin::<Repeat>(); + } +} diff --git a/third_party/rust/tokio/src/io/util/shutdown.rs b/third_party/rust/tokio/src/io/util/shutdown.rs new file mode 100644 index 0000000000..6d30b004b1 --- /dev/null +++ b/third_party/rust/tokio/src/io/util/shutdown.rs @@ -0,0 +1,46 @@ +use crate::io::AsyncWrite; + +use pin_project_lite::pin_project; +use std::future::Future; +use std::io; +use std::marker::PhantomPinned; +use std::pin::Pin; +use std::task::{Context, Poll}; + +pin_project! { + /// A future used to shutdown an I/O object. + /// + /// Created by the [`AsyncWriteExt::shutdown`][shutdown] function. + /// [shutdown]: crate::io::AsyncWriteExt::shutdown + #[must_use = "futures do nothing unless you `.await` or poll them"] + #[derive(Debug)] + pub struct Shutdown<'a, A: ?Sized> { + a: &'a mut A, + // Make this future `!Unpin` for compatibility with async trait methods. + #[pin] + _pin: PhantomPinned, + } +} + +/// Creates a future which will shutdown an I/O object. +pub(super) fn shutdown<A>(a: &mut A) -> Shutdown<'_, A> +where + A: AsyncWrite + Unpin + ?Sized, +{ + Shutdown { + a, + _pin: PhantomPinned, + } +} + +impl<A> Future for Shutdown<'_, A> +where + A: AsyncWrite + Unpin + ?Sized, +{ + type Output = io::Result<()>; + + fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> { + let me = self.project(); + Pin::new(me.a).poll_shutdown(cx) + } +} diff --git a/third_party/rust/tokio/src/io/util/sink.rs b/third_party/rust/tokio/src/io/util/sink.rs new file mode 100644 index 0000000000..05ee773fa3 --- /dev/null +++ b/third_party/rust/tokio/src/io/util/sink.rs @@ -0,0 +1,87 @@ +use crate::io::AsyncWrite; + +use std::fmt; +use std::io; +use std::pin::Pin; +use std::task::{Context, Poll}; + +cfg_io_util! { + /// An async writer which will move data into the void. + /// + /// This struct is generally created by calling [`sink`][sink]. Please + /// see the documentation of `sink()` for more details. + /// + /// This is an asynchronous version of [`std::io::Sink`][std]. + /// + /// [sink]: sink() + /// [std]: std::io::Sink + pub struct Sink { + _p: (), + } + + /// Creates an instance of an async writer which will successfully consume all + /// data. + /// + /// All calls to [`poll_write`] on the returned instance will return + /// `Poll::Ready(Ok(buf.len()))` and the contents of the buffer will not be + /// inspected. + /// + /// This is an asynchronous version of [`std::io::sink`][std]. + /// + /// [`poll_write`]: crate::io::AsyncWrite::poll_write() + /// [std]: std::io::sink + /// + /// # Examples + /// + /// ``` + /// use tokio::io::{self, AsyncWriteExt}; + /// + /// #[tokio::main] + /// async fn main() -> io::Result<()> { + /// let buffer = vec![1, 2, 3, 5, 8]; + /// let num_bytes = io::sink().write(&buffer).await?; + /// assert_eq!(num_bytes, 5); + /// Ok(()) + /// } + /// ``` + pub fn sink() -> Sink { + Sink { _p: () } + } +} + +impl AsyncWrite for Sink { + #[inline] + fn poll_write( + self: Pin<&mut Self>, + _: &mut Context<'_>, + buf: &[u8], + ) -> Poll<Result<usize, io::Error>> { + Poll::Ready(Ok(buf.len())) + } + + #[inline] + fn poll_flush(self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<Result<(), io::Error>> { + Poll::Ready(Ok(())) + } + + #[inline] + fn poll_shutdown(self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<Result<(), io::Error>> { + Poll::Ready(Ok(())) + } +} + +impl fmt::Debug for Sink { + fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result { + f.pad("Sink { .. }") + } +} + +#[cfg(test)] +mod tests { + use super::*; + + #[test] + fn assert_unpin() { + crate::is_unpin::<Sink>(); + } +} diff --git a/third_party/rust/tokio/src/io/util/split.rs b/third_party/rust/tokio/src/io/util/split.rs new file mode 100644 index 0000000000..7489c24281 --- /dev/null +++ b/third_party/rust/tokio/src/io/util/split.rs @@ -0,0 +1,121 @@ +use crate::io::util::read_until::read_until_internal; +use crate::io::AsyncBufRead; + +use pin_project_lite::pin_project; +use std::io; +use std::mem; +use std::pin::Pin; +use std::task::{Context, Poll}; + +pin_project! { + /// Splitter for the [`split`](crate::io::AsyncBufReadExt::split) method. + /// + /// A `Split` can be turned into a `Stream` with [`SplitStream`]. + /// + /// [`SplitStream`]: https://docs.rs/tokio-stream/0.1/tokio_stream/wrappers/struct.SplitStream.html + #[derive(Debug)] + #[must_use = "streams do nothing unless polled"] + #[cfg_attr(docsrs, doc(cfg(feature = "io-util")))] + pub struct Split<R> { + #[pin] + reader: R, + buf: Vec<u8>, + delim: u8, + read: usize, + } +} + +pub(crate) fn split<R>(reader: R, delim: u8) -> Split<R> +where + R: AsyncBufRead, +{ + Split { + reader, + buf: Vec::new(), + delim, + read: 0, + } +} + +impl<R> Split<R> +where + R: AsyncBufRead + Unpin, +{ + /// Returns the next segment in the stream. + /// + /// # Examples + /// + /// ``` + /// # use tokio::io::AsyncBufRead; + /// use tokio::io::AsyncBufReadExt; + /// + /// # async fn dox(my_buf_read: impl AsyncBufRead + Unpin) -> std::io::Result<()> { + /// let mut segments = my_buf_read.split(b'f'); + /// + /// while let Some(segment) = segments.next_segment().await? { + /// println!("length = {}", segment.len()) + /// } + /// # Ok(()) + /// # } + /// ``` + pub async fn next_segment(&mut self) -> io::Result<Option<Vec<u8>>> { + use crate::future::poll_fn; + + poll_fn(|cx| Pin::new(&mut *self).poll_next_segment(cx)).await + } +} + +impl<R> Split<R> +where + R: AsyncBufRead, +{ + /// Polls for the next segment in the stream. + /// + /// This method returns: + /// + /// * `Poll::Pending` if the next segment is not yet available. + /// * `Poll::Ready(Ok(Some(segment)))` if the next segment is available. + /// * `Poll::Ready(Ok(None))` if there are no more segments in this stream. + /// * `Poll::Ready(Err(err))` if an IO error occurred while reading the + /// next segment. + /// + /// When the method returns `Poll::Pending`, the `Waker` in the provided + /// `Context` is scheduled to receive a wakeup when more bytes become + /// available on the underlying IO resource. + /// + /// Note that on multiple calls to `poll_next_segment`, only the `Waker` + /// from the `Context` passed to the most recent call is scheduled to + /// receive a wakeup. + pub fn poll_next_segment( + self: Pin<&mut Self>, + cx: &mut Context<'_>, + ) -> Poll<io::Result<Option<Vec<u8>>>> { + let me = self.project(); + + let n = ready!(read_until_internal( + me.reader, cx, *me.delim, me.buf, me.read, + ))?; + // read_until_internal resets me.read to zero once it finds the delimiter + debug_assert_eq!(*me.read, 0); + + if n == 0 && me.buf.is_empty() { + return Poll::Ready(Ok(None)); + } + + if me.buf.last() == Some(me.delim) { + me.buf.pop(); + } + + Poll::Ready(Ok(Some(mem::take(me.buf)))) + } +} + +#[cfg(test)] +mod tests { + use super::*; + + #[test] + fn assert_unpin() { + crate::is_unpin::<Split<()>>(); + } +} diff --git a/third_party/rust/tokio/src/io/util/take.rs b/third_party/rust/tokio/src/io/util/take.rs new file mode 100644 index 0000000000..df2f61b9e6 --- /dev/null +++ b/third_party/rust/tokio/src/io/util/take.rs @@ -0,0 +1,137 @@ +use crate::io::{AsyncBufRead, AsyncRead, ReadBuf}; + +use pin_project_lite::pin_project; +use std::pin::Pin; +use std::task::{Context, Poll}; +use std::{cmp, io}; + +pin_project! { + /// Stream for the [`take`](super::AsyncReadExt::take) method. + #[derive(Debug)] + #[must_use = "streams do nothing unless you `.await` or poll them"] + #[cfg_attr(docsrs, doc(cfg(feature = "io-util")))] + pub struct Take<R> { + #[pin] + inner: R, + // Add '_' to avoid conflicts with `limit` method. + limit_: u64, + } +} + +pub(super) fn take<R: AsyncRead>(inner: R, limit: u64) -> Take<R> { + Take { + inner, + limit_: limit, + } +} + +impl<R: AsyncRead> Take<R> { + /// Returns the remaining number of bytes that can be + /// read before this instance will return EOF. + /// + /// # Note + /// + /// This instance may reach `EOF` after reading fewer bytes than indicated by + /// this method if the underlying [`AsyncRead`] instance reaches EOF. + pub fn limit(&self) -> u64 { + self.limit_ + } + + /// Sets the number of bytes that can be read before this instance will + /// return EOF. This is the same as constructing a new `Take` instance, so + /// the amount of bytes read and the previous limit value don't matter when + /// calling this method. + pub fn set_limit(&mut self, limit: u64) { + self.limit_ = limit + } + + /// Gets a reference to the underlying reader. + pub fn get_ref(&self) -> &R { + &self.inner + } + + /// Gets a mutable reference to the underlying reader. + /// + /// Care should be taken to avoid modifying the internal I/O state of the + /// underlying reader as doing so may corrupt the internal limit of this + /// `Take`. + pub fn get_mut(&mut self) -> &mut R { + &mut self.inner + } + + /// Gets a pinned mutable reference to the underlying reader. + /// + /// Care should be taken to avoid modifying the internal I/O state of the + /// underlying reader as doing so may corrupt the internal limit of this + /// `Take`. + pub fn get_pin_mut(self: Pin<&mut Self>) -> Pin<&mut R> { + self.project().inner + } + + /// Consumes the `Take`, returning the wrapped reader. + pub fn into_inner(self) -> R { + self.inner + } +} + +impl<R: AsyncRead> AsyncRead for Take<R> { + fn poll_read( + self: Pin<&mut Self>, + cx: &mut Context<'_>, + buf: &mut ReadBuf<'_>, + ) -> Poll<Result<(), io::Error>> { + if self.limit_ == 0 { + return Poll::Ready(Ok(())); + } + + let me = self.project(); + let mut b = buf.take(*me.limit_ as usize); + + let buf_ptr = b.filled().as_ptr(); + ready!(me.inner.poll_read(cx, &mut b))?; + assert_eq!(b.filled().as_ptr(), buf_ptr); + + let n = b.filled().len(); + + // We need to update the original ReadBuf + unsafe { + buf.assume_init(n); + } + buf.advance(n); + *me.limit_ -= n as u64; + Poll::Ready(Ok(())) + } +} + +impl<R: AsyncBufRead> AsyncBufRead for Take<R> { + fn poll_fill_buf(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<&[u8]>> { + let me = self.project(); + + // Don't call into inner reader at all at EOF because it may still block + if *me.limit_ == 0 { + return Poll::Ready(Ok(&[])); + } + + let buf = ready!(me.inner.poll_fill_buf(cx)?); + let cap = cmp::min(buf.len() as u64, *me.limit_) as usize; + Poll::Ready(Ok(&buf[..cap])) + } + + fn consume(self: Pin<&mut Self>, amt: usize) { + let me = self.project(); + // Don't let callers reset the limit by passing an overlarge value + let amt = cmp::min(amt as u64, *me.limit_) as usize; + *me.limit_ -= amt as u64; + me.inner.consume(amt); + } +} + +#[cfg(test)] +mod tests { + use super::*; + + #[test] + fn assert_unpin() { + crate::is_unpin::<Take<()>>(); + } +} diff --git a/third_party/rust/tokio/src/io/util/vec_with_initialized.rs b/third_party/rust/tokio/src/io/util/vec_with_initialized.rs new file mode 100644 index 0000000000..208cc939c1 --- /dev/null +++ b/third_party/rust/tokio/src/io/util/vec_with_initialized.rs @@ -0,0 +1,132 @@ +use crate::io::ReadBuf; +use std::mem::MaybeUninit; + +mod private { + pub trait Sealed {} + + impl Sealed for Vec<u8> {} + impl Sealed for &mut Vec<u8> {} +} + +/// A sealed trait that constrains the generic type parameter in `VecWithInitialized<V>`. That struct's safety relies +/// on certain invariants upheld by `Vec<u8>`. +pub(crate) trait VecU8: AsMut<Vec<u8>> + private::Sealed {} + +impl VecU8 for Vec<u8> {} +impl VecU8 for &mut Vec<u8> {} +/// This struct wraps a `Vec<u8>` or `&mut Vec<u8>`, combining it with a +/// `num_initialized`, which keeps track of the number of initialized bytes +/// in the unused capacity. +/// +/// The purpose of this struct is to remember how many bytes were initialized +/// through a `ReadBuf` from call to call. +/// +/// This struct has the safety invariant that the first `num_initialized` of the +/// vector's allocation must be initialized at any time. +#[derive(Debug)] +pub(crate) struct VecWithInitialized<V> { + vec: V, + // The number of initialized bytes in the vector. + // Always between `vec.len()` and `vec.capacity()`. + num_initialized: usize, +} + +impl VecWithInitialized<Vec<u8>> { + #[cfg(feature = "io-util")] + pub(crate) fn take(&mut self) -> Vec<u8> { + self.num_initialized = 0; + std::mem::take(&mut self.vec) + } +} + +impl<V> VecWithInitialized<V> +where + V: VecU8, +{ + pub(crate) fn new(mut vec: V) -> Self { + // SAFETY: The safety invariants of vector guarantee that the bytes up + // to its length are initialized. + Self { + num_initialized: vec.as_mut().len(), + vec, + } + } + + pub(crate) fn reserve(&mut self, num_bytes: usize) { + let vec = self.vec.as_mut(); + if vec.capacity() - vec.len() >= num_bytes { + return; + } + // SAFETY: Setting num_initialized to `vec.len()` is correct as + // `reserve` does not change the length of the vector. + self.num_initialized = vec.len(); + vec.reserve(num_bytes); + } + + #[cfg(feature = "io-util")] + pub(crate) fn is_empty(&mut self) -> bool { + self.vec.as_mut().is_empty() + } + + pub(crate) fn get_read_buf<'a>(&'a mut self) -> ReadBuf<'a> { + let num_initialized = self.num_initialized; + + // SAFETY: Creating the slice is safe because of the safety invariants + // on Vec<u8>. The safety invariants of `ReadBuf` will further guarantee + // that no bytes in the slice are de-initialized. + let vec = self.vec.as_mut(); + let len = vec.len(); + let cap = vec.capacity(); + let ptr = vec.as_mut_ptr().cast::<MaybeUninit<u8>>(); + let slice = unsafe { std::slice::from_raw_parts_mut::<'a, MaybeUninit<u8>>(ptr, cap) }; + + // SAFETY: This is safe because the safety invariants of + // VecWithInitialized say that the first num_initialized bytes must be + // initialized. + let mut read_buf = ReadBuf::uninit(slice); + unsafe { + read_buf.assume_init(num_initialized); + } + read_buf.set_filled(len); + + read_buf + } + + pub(crate) fn apply_read_buf(&mut self, parts: ReadBufParts) { + let vec = self.vec.as_mut(); + assert_eq!(vec.as_ptr(), parts.ptr); + + // SAFETY: + // The ReadBufParts really does point inside `self.vec` due to the above + // check, and the safety invariants of `ReadBuf` guarantee that the + // first `parts.initialized` bytes of `self.vec` really have been + // initialized. Additionally, `ReadBuf` guarantees that `parts.len` is + // at most `parts.initialized`, so the first `parts.len` bytes are also + // initialized. + // + // Note that this relies on the fact that `V` is either `Vec<u8>` or + // `&mut Vec<u8>`, so the vector returned by `self.vec.as_mut()` cannot + // change from call to call. + unsafe { + self.num_initialized = parts.initialized; + vec.set_len(parts.len); + } + } +} + +pub(crate) struct ReadBufParts { + // Pointer is only used to check that the ReadBuf actually came from the + // right VecWithInitialized. + ptr: *const u8, + len: usize, + initialized: usize, +} + +// This is needed to release the borrow on `VecWithInitialized<V>`. +pub(crate) fn into_read_buf_parts(rb: ReadBuf<'_>) -> ReadBufParts { + ReadBufParts { + ptr: rb.filled().as_ptr(), + len: rb.filled().len(), + initialized: rb.initialized().len(), + } +} diff --git a/third_party/rust/tokio/src/io/util/write.rs b/third_party/rust/tokio/src/io/util/write.rs new file mode 100644 index 0000000000..92169ebc1d --- /dev/null +++ b/third_party/rust/tokio/src/io/util/write.rs @@ -0,0 +1,46 @@ +use crate::io::AsyncWrite; + +use pin_project_lite::pin_project; +use std::future::Future; +use std::io; +use std::marker::PhantomPinned; +use std::pin::Pin; +use std::task::{Context, Poll}; + +pin_project! { + /// A future to write some of the buffer to an `AsyncWrite`. + #[derive(Debug)] + #[must_use = "futures do nothing unless you `.await` or poll them"] + pub struct Write<'a, W: ?Sized> { + writer: &'a mut W, + buf: &'a [u8], + // Make this future `!Unpin` for compatibility with async trait methods. + #[pin] + _pin: PhantomPinned, + } +} + +/// Tries to write some bytes from the given `buf` to the writer in an +/// asynchronous manner, returning a future. +pub(crate) fn write<'a, W>(writer: &'a mut W, buf: &'a [u8]) -> Write<'a, W> +where + W: AsyncWrite + Unpin + ?Sized, +{ + Write { + writer, + buf, + _pin: PhantomPinned, + } +} + +impl<W> Future for Write<'_, W> +where + W: AsyncWrite + Unpin + ?Sized, +{ + type Output = io::Result<usize>; + + fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<usize>> { + let me = self.project(); + Pin::new(&mut *me.writer).poll_write(cx, me.buf) + } +} diff --git a/third_party/rust/tokio/src/io/util/write_all.rs b/third_party/rust/tokio/src/io/util/write_all.rs new file mode 100644 index 0000000000..abd3e39d31 --- /dev/null +++ b/third_party/rust/tokio/src/io/util/write_all.rs @@ -0,0 +1,55 @@ +use crate::io::AsyncWrite; + +use pin_project_lite::pin_project; +use std::future::Future; +use std::io; +use std::marker::PhantomPinned; +use std::mem; +use std::pin::Pin; +use std::task::{Context, Poll}; + +pin_project! { + #[derive(Debug)] + #[must_use = "futures do nothing unless you `.await` or poll them"] + pub struct WriteAll<'a, W: ?Sized> { + writer: &'a mut W, + buf: &'a [u8], + // Make this future `!Unpin` for compatibility with async trait methods. + #[pin] + _pin: PhantomPinned, + } +} + +pub(crate) fn write_all<'a, W>(writer: &'a mut W, buf: &'a [u8]) -> WriteAll<'a, W> +where + W: AsyncWrite + Unpin + ?Sized, +{ + WriteAll { + writer, + buf, + _pin: PhantomPinned, + } +} + +impl<W> Future for WriteAll<'_, W> +where + W: AsyncWrite + Unpin + ?Sized, +{ + type Output = io::Result<()>; + + fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<()>> { + let me = self.project(); + while !me.buf.is_empty() { + let n = ready!(Pin::new(&mut *me.writer).poll_write(cx, me.buf))?; + { + let (_, rest) = mem::take(&mut *me.buf).split_at(n); + *me.buf = rest; + } + if n == 0 { + return Poll::Ready(Err(io::ErrorKind::WriteZero.into())); + } + } + + Poll::Ready(Ok(())) + } +} diff --git a/third_party/rust/tokio/src/io/util/write_all_buf.rs b/third_party/rust/tokio/src/io/util/write_all_buf.rs new file mode 100644 index 0000000000..05af7fe99b --- /dev/null +++ b/third_party/rust/tokio/src/io/util/write_all_buf.rs @@ -0,0 +1,56 @@ +use crate::io::AsyncWrite; + +use bytes::Buf; +use pin_project_lite::pin_project; +use std::future::Future; +use std::io; +use std::marker::PhantomPinned; +use std::pin::Pin; +use std::task::{Context, Poll}; + +pin_project! { + /// A future to write some of the buffer to an `AsyncWrite`. + #[derive(Debug)] + #[must_use = "futures do nothing unless you `.await` or poll them"] + pub struct WriteAllBuf<'a, W, B> { + writer: &'a mut W, + buf: &'a mut B, + #[pin] + _pin: PhantomPinned, + } +} + +/// Tries to write some bytes from the given `buf` to the writer in an +/// asynchronous manner, returning a future. +pub(crate) fn write_all_buf<'a, W, B>(writer: &'a mut W, buf: &'a mut B) -> WriteAllBuf<'a, W, B> +where + W: AsyncWrite + Unpin, + B: Buf, +{ + WriteAllBuf { + writer, + buf, + _pin: PhantomPinned, + } +} + +impl<W, B> Future for WriteAllBuf<'_, W, B> +where + W: AsyncWrite + Unpin, + B: Buf, +{ + type Output = io::Result<()>; + + fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<()>> { + let me = self.project(); + while me.buf.has_remaining() { + let n = ready!(Pin::new(&mut *me.writer).poll_write(cx, me.buf.chunk())?); + me.buf.advance(n); + if n == 0 { + return Poll::Ready(Err(io::ErrorKind::WriteZero.into())); + } + } + + Poll::Ready(Ok(())) + } +} diff --git a/third_party/rust/tokio/src/io/util/write_buf.rs b/third_party/rust/tokio/src/io/util/write_buf.rs new file mode 100644 index 0000000000..82fd7a759f --- /dev/null +++ b/third_party/rust/tokio/src/io/util/write_buf.rs @@ -0,0 +1,55 @@ +use crate::io::AsyncWrite; + +use bytes::Buf; +use pin_project_lite::pin_project; +use std::future::Future; +use std::io; +use std::marker::PhantomPinned; +use std::pin::Pin; +use std::task::{Context, Poll}; + +pin_project! { + /// A future to write some of the buffer to an `AsyncWrite`. + #[derive(Debug)] + #[must_use = "futures do nothing unless you `.await` or poll them"] + pub struct WriteBuf<'a, W, B> { + writer: &'a mut W, + buf: &'a mut B, + #[pin] + _pin: PhantomPinned, + } +} + +/// Tries to write some bytes from the given `buf` to the writer in an +/// asynchronous manner, returning a future. +pub(crate) fn write_buf<'a, W, B>(writer: &'a mut W, buf: &'a mut B) -> WriteBuf<'a, W, B> +where + W: AsyncWrite + Unpin, + B: Buf, +{ + WriteBuf { + writer, + buf, + _pin: PhantomPinned, + } +} + +impl<W, B> Future for WriteBuf<'_, W, B> +where + W: AsyncWrite + Unpin, + B: Buf, +{ + type Output = io::Result<usize>; + + fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<usize>> { + let me = self.project(); + + if !me.buf.has_remaining() { + return Poll::Ready(Ok(0)); + } + + let n = ready!(Pin::new(me.writer).poll_write(cx, me.buf.chunk()))?; + me.buf.advance(n); + Poll::Ready(Ok(n)) + } +} diff --git a/third_party/rust/tokio/src/io/util/write_int.rs b/third_party/rust/tokio/src/io/util/write_int.rs new file mode 100644 index 0000000000..63cd49126f --- /dev/null +++ b/third_party/rust/tokio/src/io/util/write_int.rs @@ -0,0 +1,152 @@ +use crate::io::AsyncWrite; + +use bytes::BufMut; +use pin_project_lite::pin_project; +use std::future::Future; +use std::io; +use std::marker::PhantomPinned; +use std::mem::size_of; +use std::pin::Pin; +use std::task::{Context, Poll}; + +macro_rules! writer { + ($name:ident, $ty:ty, $writer:ident) => { + writer!($name, $ty, $writer, size_of::<$ty>()); + }; + ($name:ident, $ty:ty, $writer:ident, $bytes:expr) => { + pin_project! { + #[doc(hidden)] + #[must_use = "futures do nothing unless you `.await` or poll them"] + pub struct $name<W> { + #[pin] + dst: W, + buf: [u8; $bytes], + written: u8, + // Make this future `!Unpin` for compatibility with async trait methods. + #[pin] + _pin: PhantomPinned, + } + } + + impl<W> $name<W> { + pub(crate) fn new(w: W, value: $ty) -> Self { + let mut writer = Self { + buf: [0; $bytes], + written: 0, + dst: w, + _pin: PhantomPinned, + }; + BufMut::$writer(&mut &mut writer.buf[..], value); + writer + } + } + + impl<W> Future for $name<W> + where + W: AsyncWrite, + { + type Output = io::Result<()>; + + fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> { + let mut me = self.project(); + + if *me.written == $bytes as u8 { + return Poll::Ready(Ok(())); + } + + while *me.written < $bytes as u8 { + *me.written += match me + .dst + .as_mut() + .poll_write(cx, &me.buf[*me.written as usize..]) + { + Poll::Pending => return Poll::Pending, + Poll::Ready(Err(e)) => return Poll::Ready(Err(e.into())), + Poll::Ready(Ok(0)) => { + return Poll::Ready(Err(io::ErrorKind::WriteZero.into())); + } + Poll::Ready(Ok(n)) => n as u8, + }; + } + Poll::Ready(Ok(())) + } + } + }; +} + +macro_rules! writer8 { + ($name:ident, $ty:ty) => { + pin_project! { + #[doc(hidden)] + #[must_use = "futures do nothing unless you `.await` or poll them"] + pub struct $name<W> { + #[pin] + dst: W, + byte: $ty, + // Make this future `!Unpin` for compatibility with async trait methods. + #[pin] + _pin: PhantomPinned, + } + } + + impl<W> $name<W> { + pub(crate) fn new(dst: W, byte: $ty) -> Self { + Self { + dst, + byte, + _pin: PhantomPinned, + } + } + } + + impl<W> Future for $name<W> + where + W: AsyncWrite, + { + type Output = io::Result<()>; + + fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> { + let me = self.project(); + + let buf = [*me.byte as u8]; + + match me.dst.poll_write(cx, &buf[..]) { + Poll::Pending => Poll::Pending, + Poll::Ready(Err(e)) => Poll::Ready(Err(e.into())), + Poll::Ready(Ok(0)) => Poll::Ready(Err(io::ErrorKind::WriteZero.into())), + Poll::Ready(Ok(1)) => Poll::Ready(Ok(())), + Poll::Ready(Ok(_)) => unreachable!(), + } + } + } + }; +} + +writer8!(WriteU8, u8); +writer8!(WriteI8, i8); + +writer!(WriteU16, u16, put_u16); +writer!(WriteU32, u32, put_u32); +writer!(WriteU64, u64, put_u64); +writer!(WriteU128, u128, put_u128); + +writer!(WriteI16, i16, put_i16); +writer!(WriteI32, i32, put_i32); +writer!(WriteI64, i64, put_i64); +writer!(WriteI128, i128, put_i128); + +writer!(WriteF32, f32, put_f32); +writer!(WriteF64, f64, put_f64); + +writer!(WriteU16Le, u16, put_u16_le); +writer!(WriteU32Le, u32, put_u32_le); +writer!(WriteU64Le, u64, put_u64_le); +writer!(WriteU128Le, u128, put_u128_le); + +writer!(WriteI16Le, i16, put_i16_le); +writer!(WriteI32Le, i32, put_i32_le); +writer!(WriteI64Le, i64, put_i64_le); +writer!(WriteI128Le, i128, put_i128_le); + +writer!(WriteF32Le, f32, put_f32_le); +writer!(WriteF64Le, f64, put_f64_le); diff --git a/third_party/rust/tokio/src/io/util/write_vectored.rs b/third_party/rust/tokio/src/io/util/write_vectored.rs new file mode 100644 index 0000000000..be40322943 --- /dev/null +++ b/third_party/rust/tokio/src/io/util/write_vectored.rs @@ -0,0 +1,47 @@ +use crate::io::AsyncWrite; + +use pin_project_lite::pin_project; +use std::io; +use std::marker::PhantomPinned; +use std::pin::Pin; +use std::task::{Context, Poll}; +use std::{future::Future, io::IoSlice}; + +pin_project! { + /// A future to write a slice of buffers to an `AsyncWrite`. + #[derive(Debug)] + #[must_use = "futures do nothing unless you `.await` or poll them"] + pub struct WriteVectored<'a, 'b, W: ?Sized> { + writer: &'a mut W, + bufs: &'a [IoSlice<'b>], + // Make this future `!Unpin` for compatibility with async trait methods. + #[pin] + _pin: PhantomPinned, + } +} + +pub(crate) fn write_vectored<'a, 'b, W>( + writer: &'a mut W, + bufs: &'a [IoSlice<'b>], +) -> WriteVectored<'a, 'b, W> +where + W: AsyncWrite + Unpin + ?Sized, +{ + WriteVectored { + writer, + bufs, + _pin: PhantomPinned, + } +} + +impl<W> Future for WriteVectored<'_, '_, W> +where + W: AsyncWrite + Unpin + ?Sized, +{ + type Output = io::Result<usize>; + + fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<usize>> { + let me = self.project(); + Pin::new(&mut *me.writer).poll_write_vectored(cx, me.bufs) + } +} |