Rollup merge of #59852 - alexcrichton:more-vectored, r=sfackler

std: Add `{read,write}_vectored` for more types

This commit implements the `{read,write}_vectored` methods on more types
in the standard library, namely:

* `std::fs::File`
* `std::process::ChildStd{in,out,err}`
* `std::io::Std{in,out,err}`
* `std::io::Std{in,out,err}Lock`
* `std::io::Std{in,out,err}Raw`

Where supported the OS implementations hook up to native support,
otherwise it falls back to the already-defaulted implementation.

2 files changed, 24 insertions, 4 deletions

diff --git a/src/libstd/sys/wasi/pipe.rs b/src/libstd/sys/wasi/pipe.rs
index 2582b993b60..aa6bf8076f6 100644
--- a/src/libstd/sys/wasi/pipe.rs
+++ b/src/libstd/sys/wasi/pipe.rs
@@ -1,4 +1,4 @@
-use crate::io;
+use crate::io::{self, IoVec, IoVecMut};
 use crate::sys::Void;
 
 pub struct AnonPipe(Void);
@@ -8,10 +8,18 @@ impl AnonPipe {
         match self.0 {}
     }
 
+    pub fn read_vectored(&self, _bufs: &mut [IoVecMut<'_>]) -> io::Result<usize> {
+        match self.0 {}
+    }
+
     pub fn write(&self, _buf: &[u8]) -> io::Result<usize> {
         match self.0 {}
     }
 
+    pub fn write_vectored(&self, _bufs: &[IoVec<'_>]) -> io::Result<usize> {
+        match self.0 {}
+    }
+
     pub fn diverge(&self) -> ! {
         match self.0 {}
     }
diff --git a/src/libstd/sys/wasi/stdio.rs b/src/libstd/sys/wasi/stdio.rs
index 19294788666..bdad4084891 100644
--- a/src/libstd/sys/wasi/stdio.rs
+++ b/src/libstd/sys/wasi/stdio.rs
@@ -13,8 +13,12 @@ impl Stdin {
     }
 
     pub fn read(&self, data: &mut [u8]) -> io::Result<usize> {
+        self.read_vectored(&mut [IoVecMut::new(data)])
+    }
+
+    pub fn read_vectored(&self, data: &mut [IoVecMut<'_>]) -> io::Result<usize> {
         ManuallyDrop::new(unsafe { WasiFd::from_raw(libc::STDIN_FILENO as u32) })
-            .read(&mut [IoVecMut::new(data)])
+            .read(data)
     }
 }
 
@@ -24,8 +28,12 @@ impl Stdout {
     }
 
     pub fn write(&self, data: &[u8]) -> io::Result<usize> {
+        self.write_vectored(&[IoVec::new(data)])
+    }
+
+    pub fn write_vectored(&self, data: &[IoVec<'_>]) -> io::Result<usize> {
         ManuallyDrop::new(unsafe { WasiFd::from_raw(libc::STDOUT_FILENO as u32) })
-            .write(&[IoVec::new(data)])
+            .write(data)
     }
 
     pub fn flush(&self) -> io::Result<()> {
@@ -39,8 +47,12 @@ impl Stderr {
     }
 
     pub fn write(&self, data: &[u8]) -> io::Result<usize> {
+        self.write_vectored(&[IoVec::new(data)])
+    }
+
+    pub fn write_vectored(&self, data: &[IoVec<'_>]) -> io::Result<usize> {
         ManuallyDrop::new(unsafe { WasiFd::from_raw(libc::STDERR_FILENO as u32) })
-            .write(&[IoVec::new(data)])
+            .write(data)
     }
 
     pub fn flush(&self) -> io::Result<()> {