Use std::io::IoSlice[Mut] on AsyncRead/AsyncWrite

Also, this renames `poll_vectored_*` to `poll_*_vectored` to make it in
the same order as std.

Author: taiki-e

futures-io/Cargo.toml

@@ -15,12 +15,11 @@ The `AsyncRead` and `AsyncWrite` traits for the futures-rs library.
 name = "futures_io"
 
 [features]
-std = ["futures-core-preview/std", "iovec"]
+std = ["futures-core-preview/std"]
 default = ["std"]
 
 [dependencies]
 futures-core-preview = { path = "../futures-core", version = "=0.3.0-alpha.15", default-features = false }
-iovec = { version = "0.1", optional = true }
 
 [dev-dependencies]
 futures-preview = { path = "../futures", version = "=0.3.0-alpha.15" }

futures-io/src/lib.rs

@@ -20,14 +20,13 @@ mod if_std {
     use std::pin::Pin;
     use std::ptr;
 
-    // Re-export IoVec for convenience
-    pub use iovec::IoVec;
-
     // Re-export some types from `std::io` so that users don't have to deal
     // with conflicts when `use`ing `futures::io` and `std::io`.
     pub use self::StdIo::Error as Error;
     pub use self::StdIo::ErrorKind as ErrorKind;
     pub use self::StdIo::Result as Result;
+    pub use self::StdIo::IoSlice as IoSlice;
+    pub use self::StdIo::IoSliceMut as IoSliceMut;
     pub use self::StdIo::SeekFrom as SeekFrom;
 
     /// A type used to conditionally initialize buffers passed to `AsyncRead`
@@ -134,7 +133,7 @@ mod if_std {
         /// `Interrupted`.  Implementations must convert `WouldBlock` into
         /// `Poll::Pending` and either internally retry or convert
         /// `Interrupted` into another error kind.
-        fn poll_vectored_read(self: Pin<&mut Self>, cx: &mut Context<'_>, vec: &mut [&mut IoVec])
+        fn poll_read_vectored(self: Pin<&mut Self>, cx: &mut Context<'_>, vec: &mut [IoSliceMut<'_>])
             -> Poll<Result<usize>>
         {
             if let Some(ref mut first_iovec) = vec.get_mut(0) {
@@ -195,13 +194,13 @@ mod if_std {
         /// `Interrupted`.  Implementations must convert `WouldBlock` into
         /// `Poll::Pending` and either internally retry or convert
         /// `Interrupted` into another error kind.
-        fn poll_vectored_write(self: Pin<&mut Self>, cx: &mut Context<'_>, vec: &[&IoVec])
+        fn poll_write_vectored(self: Pin<&mut Self>, cx: &mut Context<'_>, bufs: &[IoSlice<'_>])
             -> Poll<Result<usize>>
         {
-            if let Some(ref first_iovec) = vec.get(0) {
+            if let Some(ref first_iovec) = bufs.get(0) {
                 self.poll_write(cx, &*first_iovec)
             } else {
-                // `vec` is empty.
+                // `bufs` is empty.
                 Poll::Ready(Ok(0))
             }
         }
@@ -335,10 +334,10 @@ mod if_std {
                 Pin::new(&mut **self).poll_read(cx, buf)
             }
 
-            fn poll_vectored_read(mut self: Pin<&mut Self>, cx: &mut Context<'_>, vec: &mut [&mut IoVec])
+            fn poll_read_vectored(mut self: Pin<&mut Self>, cx: &mut Context<'_>, vec: &mut [IoSliceMut<'_>])
                 -> Poll<Result<usize>>
             {
-                Pin::new(&mut **self).poll_vectored_read(cx, vec)
+                Pin::new(&mut **self).poll_read_vectored(cx, vec)
             }
         }
     }
@@ -366,10 +365,10 @@ mod if_std {
             Pin::get_mut(self).as_mut().poll_read(cx, buf)
         }
 
-        fn poll_vectored_read(self: Pin<&mut Self>, cx: &mut Context<'_>, vec: &mut [&mut IoVec])
+        fn poll_read_vectored(self: Pin<&mut Self>, cx: &mut Context<'_>, vec: &mut [IoSliceMut<'_>])
             -> Poll<Result<usize>>
         {
-            Pin::get_mut(self).as_mut().poll_vectored_read(cx, vec)
+            Pin::get_mut(self).as_mut().poll_read_vectored(cx, vec)
         }
     }
 
@@ -386,6 +385,12 @@ mod if_std {
             {
                 Poll::Ready(StdIo::Read::read(&mut *self, buf))
             }
+
+            fn poll_read_vectored(mut self: Pin<&mut Self>, _: &mut Context<'_>, vec: &mut [IoSliceMut<'_>])
+                -> Poll<Result<usize>>
+            {
+                Poll::Ready(StdIo::Read::read_vectored(&mut *self, vec))
+            }
         }
     }
 
@@ -413,10 +418,10 @@ mod if_std {
                 Pin::new(&mut **self).poll_write(cx, buf)
             }
 
-            fn poll_vectored_write(mut self: Pin<&mut Self>, cx: &mut Context<'_>, vec: &[&IoVec])
+            fn poll_write_vectored(mut self: Pin<&mut Self>, cx: &mut Context<'_>, bufs: &[IoSlice<'_>])
                 -> Poll<Result<usize>>
             {
-                Pin::new(&mut **self).poll_vectored_write(cx, vec)
+                Pin::new(&mut **self).poll_write_vectored(cx, bufs)
             }
 
             fn poll_flush(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<()>> {
@@ -448,10 +453,10 @@ mod if_std {
             Pin::get_mut(self).as_mut().poll_write(cx, buf)
         }
 
-        fn poll_vectored_write(self: Pin<&mut Self>, cx: &mut Context<'_>, vec: &[&IoVec])
+        fn poll_write_vectored(self: Pin<&mut Self>, cx: &mut Context<'_>, bufs: &[IoSlice<'_>])
             -> Poll<Result<usize>>
         {
-            Pin::get_mut(self).as_mut().poll_vectored_write(cx, vec)
+            Pin::get_mut(self).as_mut().poll_write_vectored(cx, bufs)
         }
 
         fn poll_flush(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Result<()>> {
@@ -471,6 +476,12 @@ mod if_std {
                 Poll::Ready(StdIo::Write::write(&mut *self, buf))
             }
 
+            fn poll_write_vectored(mut self: Pin<&mut Self>, _: &mut Context<'_>, bufs: &[IoSlice<'_>])
+                -> Poll<Result<usize>>
+            {
+                Poll::Ready(StdIo::Write::write_vectored(&mut *self, bufs))
+            }
+
             fn poll_flush(mut self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<Result<()>> {
                 Poll::Ready(StdIo::Write::flush(&mut *self))
             }
@@ -499,6 +510,12 @@ mod if_std {
             Poll::Ready(result)
         }
 
+        fn poll_write_vectored(self: Pin<&mut Self>, _: &mut Context<'_>, bufs: &[IoSlice<'_>])
+            -> Poll<Result<usize>>
+        {
+            Poll::Ready(StdIo::Write::write_vectored(&mut self.get_mut().get_mut().as_mut(), bufs))
+        }
+
         fn poll_flush(self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<Result<()>> {
             Poll::Ready(StdIo::Write::flush(&mut self.get_mut().get_mut().as_mut()))
         }

futures-util/src/io/allow_std.rs

@@ -1,5 +1,5 @@
 use futures_core::task::{Context, Poll};
-use futures_io::{AsyncRead, AsyncWrite, AsyncSeek, AsyncBufRead};
+use futures_io::{AsyncRead, AsyncWrite, AsyncSeek, AsyncBufRead, IoSlice, IoSliceMut, SeekFrom};
 use std::{fmt, io};
 use std::pin::Pin;
 
@@ -62,6 +62,9 @@ impl<T> io::Write for AllowStdIo<T> where T: io::Write {
     fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
         self.0.write(buf)
     }
+    fn write_vectored(&mut self, bufs: &[IoSlice<'_>]) -> io::Result<usize> {
+        self.0.write_vectored(bufs)
+    }
     fn flush(&mut self) -> io::Result<()> {
         self.0.flush()
     }
@@ -80,6 +83,12 @@ impl<T> AsyncWrite for AllowStdIo<T> where T: io::Write {
         Poll::Ready(Ok(try_with_interrupt!(self.0.write(buf))))
     }
 
+    fn poll_write_vectored(mut self: Pin<&mut Self>, _: &mut Context<'_>, bufs: &[IoSlice<'_>])
+        -> Poll<io::Result<usize>>
+    {
+        Poll::Ready(Ok(try_with_interrupt!(self.0.write_vectored(bufs))))
+    }
+
     fn poll_flush(mut self: Pin<&mut Self>, _: &mut Context<'_>) -> Poll<io::Result<()>> {
         try_with_interrupt!(self.0.flush());
         Poll::Ready(Ok(()))
@@ -94,6 +103,9 @@ impl<T> io::Read for AllowStdIo<T> where T: io::Read {
     fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
         self.0.read(buf)
     }
+    fn read_vectored(&mut self, bufs: &mut [IoSliceMut<'_>]) -> io::Result<usize> {
+        self.0.read_vectored(bufs)
+    }
     // TODO: implement the `initializer` fn when it stabilizes.
     // See rust-lang/rust #42788
     fn read_to_end(&mut self, buf: &mut Vec<u8>) -> io::Result<usize> {
@@ -113,16 +125,22 @@ impl<T> AsyncRead for AllowStdIo<T> where T: io::Read {
     {
         Poll::Ready(Ok(try_with_interrupt!(self.0.read(buf))))
     }
+
+    fn poll_read_vectored(mut self: Pin<&mut Self>, _: &mut Context<'_>, bufs: &mut [IoSliceMut<'_>])
+        -> Poll<io::Result<usize>>
+    {
+        Poll::Ready(Ok(try_with_interrupt!(self.0.read_vectored(bufs))))
+    }
 }
 
 impl<T> io::Seek for AllowStdIo<T> where T: io::Seek {
-    fn seek(&mut self, pos: io::SeekFrom) -> io::Result<u64> {
+    fn seek(&mut self, pos: SeekFrom) -> io::Result<u64> {
         self.0.seek(pos)
     }
 }
 
 impl<T> AsyncSeek for AllowStdIo<T> where T: io::Seek {
-    fn poll_seek(mut self: Pin<&mut Self>, _: &mut Context<'_>, pos: io::SeekFrom)
+    fn poll_seek(mut self: Pin<&mut Self>, _: &mut Context<'_>, pos: SeekFrom)
         -> Poll<io::Result<u64>>
     {
         Poll::Ready(Ok(try_with_interrupt!(self.0.seek(pos))))

futures-util/src/io/mod.rs

@@ -6,7 +6,7 @@
 //! to the `AsyncRead` and `AsyncWrite` types.
 
 pub use futures_io::{
-    AsyncRead, AsyncWrite, AsyncSeek, AsyncBufRead, IoVec, SeekFrom,
+    AsyncRead, AsyncWrite, AsyncSeek, AsyncBufRead, IoSlice, IoSliceMut, SeekFrom,
 };
 
 #[cfg(feature = "io-compat")] use crate::compat::Compat;

futures-util/src/io/split.rs

@@ -1,6 +1,6 @@
 use crate::lock::BiLock;
 use futures_core::task::{Context, Poll};
-use futures_io::{AsyncRead, AsyncWrite, IoVec};
+use futures_io::{AsyncRead, AsyncWrite, IoSlice, IoSliceMut};
 use std::io;
 use std::pin::Pin;
 
@@ -43,10 +43,10 @@ impl<R: AsyncRead> AsyncRead for ReadHalf<R> {
         lock_and_then(&self.handle, cx, |l, cx| l.poll_read(cx, buf))
     }
 
-    fn poll_vectored_read(self: Pin<&mut Self>, cx: &mut Context<'_>, vec: &mut [&mut IoVec])
+    fn poll_read_vectored(self: Pin<&mut Self>, cx: &mut Context<'_>, vec: &mut [IoSliceMut<'_>])
         -> Poll<io::Result<usize>>
     {
-        lock_and_then(&self.handle, cx, |l, cx| l.poll_vectored_read(cx, vec))
+        lock_and_then(&self.handle, cx, |l, cx| l.poll_read_vectored(cx, vec))
     }
 }
 
@@ -57,10 +57,10 @@ impl<W: AsyncWrite> AsyncWrite for WriteHalf<W> {
         lock_and_then(&self.handle, cx, |l, cx| l.poll_write(cx, buf))
     }
 
-    fn poll_vectored_write(self: Pin<&mut Self>, cx: &mut Context<'_>, vec: &[&IoVec])
+    fn poll_write_vectored(self: Pin<&mut Self>, cx: &mut Context<'_>, bufs: &[IoSlice<'_>])
         -> Poll<io::Result<usize>>
     {
-        lock_and_then(&self.handle, cx, |l, cx| l.poll_vectored_write(cx, vec))
+        lock_and_then(&self.handle, cx, |l, cx| l.poll_write_vectored(cx, bufs))
     }
 
     fn poll_flush(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<io::Result<()>> {

futures/src/lib.rs

@@ -272,8 +272,9 @@ pub mod io {
 
     pub use futures_io::{
         AsyncRead, AsyncWrite, AsyncSeek, AsyncBufRead, Error, ErrorKind,
-        Initializer, IoVec, Result, SeekFrom,
+        Initializer, IoSlice, IoSliceMut, Result, SeekFrom,
     };
+
     pub use futures_util::io::{
         AsyncReadExt, AsyncWriteExt, AsyncSeekExt, AsyncBufReadExt, AllowStdIo,
         Close, CopyInto, Flush, Read, ReadExact, ReadHalf, ReadToEnd, ReadUntil,