Refactor Windows stdio and remove stdin double buffering

src/libstd/io/mod.rs

@@ -286,6 +286,9 @@ pub use self::stdio::{_print, _eprint};
 #[doc(no_inline, hidden)]
 pub use self::stdio::{set_panic, set_print};
 
+// Used inside the standard library for panic output.
+pub(crate) use self::stdio::stderr_raw;
+
 pub mod prelude;
 mod buffered;
 mod cursor;

src/libstd/io/stdio.rs

@@ -32,7 +32,9 @@ struct StdoutRaw(stdio::Stdout);
 ///
 /// This handle is not synchronized or buffered in any fashion. Constructed via
 /// the `std::io::stdio::stderr_raw` function.
-struct StderrRaw(stdio::Stderr);
+///
+/// Not exposed, but used inside the standard library for panic output.
+pub(crate) struct StderrRaw(stdio::Stderr);
 
 /// Constructs a new raw handle to the standard input of this process.
 ///
@@ -61,7 +63,9 @@ fn stdout_raw() -> io::Result<StdoutRaw> { stdio::Stdout::new().map(StdoutRaw) }
 ///
 /// The returned handle has no external synchronization or buffering layered on
 /// top.
-fn stderr_raw() -> io::Result<StderrRaw> { stdio::Stderr::new().map(StderrRaw) }
+///
+/// Not exposed, but used inside the standard library for panic output.
+pub(crate) fn stderr_raw() -> io::Result<StderrRaw> { stdio::Stderr::new().map(StderrRaw) }
 
 impl Read for StdinRaw {
     fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> { self.0.read(buf) }

src/libstd/sys/cloudabi/stdio.rs

@@ -9,8 +9,10 @@ impl Stdin {
     pub fn new() -> io::Result<Stdin> {
         Ok(Stdin(()))
     }
+}
 
-    pub fn read(&self, _: &mut [u8]) -> io::Result<usize> {
+impl io::Read for Stdin {
+    fn read(&mut self, _buf: &mut [u8]) -> io::Result<usize> {
         Ok(0)
     }
 }
@@ -19,15 +21,17 @@ impl Stdout {
     pub fn new() -> io::Result<Stdout> {
         Ok(Stdout(()))
     }
+}
 
-    pub fn write(&self, _: &[u8]) -> io::Result<usize> {
+impl io::Write for Stdout {
+    fn write(&mut self, _buf: &[u8]) -> io::Result<usize> {
         Err(io::Error::new(
             io::ErrorKind::BrokenPipe,
             "Stdout is not connected to any output in this environment",
         ))
     }
 
-    pub fn flush(&self) -> io::Result<()> {
+    fn flush(&mut self) -> io::Result<()> {
         Ok(())
     }
 }
@@ -36,29 +40,18 @@ impl Stderr {
     pub fn new() -> io::Result<Stderr> {
         Ok(Stderr(()))
     }
+}
 
-    pub fn write(&self, _: &[u8]) -> io::Result<usize> {
+impl io::Write for Stderr {
+    fn write(&mut self, _buf: &[u8]) -> io::Result<usize> {
         Err(io::Error::new(
             io::ErrorKind::BrokenPipe,
             "Stderr is not connected to any output in this environment",
         ))
     }
 
-    pub fn flush(&self) -> io::Result<()> {
-        Ok(())
-    }
-}
-
-// FIXME: right now this raw stderr handle is used in a few places because
-//        std::io::stderr_raw isn't exposed, but once that's exposed this impl
-//        should go away
-impl io::Write for Stderr {
-    fn write(&mut self, data: &[u8]) -> io::Result<usize> {
-        Stderr::write(self, data)
-    }
-
     fn flush(&mut self) -> io::Result<()> {
-        Stderr::flush(self)
+        Ok(())
     }
 }
 

src/libstd/sys/redox/stdio.rs

@@ -8,55 +8,48 @@ pub struct Stderr(());
 
 impl Stdin {
     pub fn new() -> io::Result<Stdin> { Ok(Stdin(())) }
+}
 
-    pub fn read(&self, data: &mut [u8]) -> io::Result<usize> {
+impl io::Read for Stdin {
+    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
         let fd = FileDesc::new(0);
-        let ret = fd.read(data);
+        let ret = fd.read(buf);
         fd.into_raw();
         ret
     }
 }
 
 impl Stdout {
     pub fn new() -> io::Result<Stdout> { Ok(Stdout(())) }
+}
 
-    pub fn write(&self, data: &[u8]) -> io::Result<usize> {
+impl io::Write for Stdout {
+    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
         let fd = FileDesc::new(1);
-        let ret = fd.write(data);
+        let ret = fd.write(buf);
         fd.into_raw();
         ret
     }
 
-    pub fn flush(&self) -> io::Result<()> {
+    fn flush(&mut self) -> io::Result<()> {
         cvt(syscall::fsync(1)).and(Ok(()))
     }
 }
 
 impl Stderr {
     pub fn new() -> io::Result<Stderr> { Ok(Stderr(())) }
+}
 
-    pub fn write(&self, data: &[u8]) -> io::Result<usize> {
+impl io::Write for Stderr {
+    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
         let fd = FileDesc::new(2);
-        let ret = fd.write(data);
+        let ret = fd.write(buf);
         fd.into_raw();
         ret
     }
 
-    pub fn flush(&self) -> io::Result<()> {
-        cvt(syscall::fsync(2)).and(Ok(()))
-    }
-}
-
-// FIXME: right now this raw stderr handle is used in a few places because
-//        std::io::stderr_raw isn't exposed, but once that's exposed this impl
-//        should go away
-impl io::Write for Stderr {
-    fn write(&mut self, data: &[u8]) -> io::Result<usize> {
-        Stderr::write(self, data)
-    }
-
     fn flush(&mut self) -> io::Result<()> {
-        Stderr::flush(self)
+        cvt(syscall::fsync(2)).and(Ok(()))
     }
 }
 
@@ -67,5 +60,5 @@ pub fn is_ebadf(err: &io::Error) -> bool {
 pub const STDIN_BUF_SIZE: usize = ::sys_common::io::DEFAULT_BUF_SIZE;
 
 pub fn panic_output() -> Option<impl io::Write> {
-    Stderr::new().ok()
+    io::stderr_raw().ok()
 }

src/libstd/sys/sgx/stdio.rs

@@ -16,46 +16,39 @@ fn with_std_fd<F: FnOnce(&FileDesc) -> R, R>(fd: abi::Fd, f: F) -> R {
 
 impl Stdin {
     pub fn new() -> io::Result<Stdin> { Ok(Stdin(())) }
+}
 
-    pub fn read(&self, data: &mut [u8]) -> io::Result<usize> {
-        with_std_fd(abi::FD_STDIN, |fd| fd.read(data))
+impl io::Read for Stdin {
+    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
+        with_std_fd(abi::FD_STDIN, |fd| fd.read(buf))
     }
 }
 
 impl Stdout {
     pub fn new() -> io::Result<Stdout> { Ok(Stdout(())) }
+}
 
-    pub fn write(&self, data: &[u8]) -> io::Result<usize> {
-        with_std_fd(abi::FD_STDOUT, |fd| fd.write(data))
+impl io::Write for Stdout {
+    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
+        with_std_fd(abi::FD_STDOUT, |fd| fd.write(buf))
     }
 
-    pub fn flush(&self) -> io::Result<()> {
+    fn flush(&mut self) -> io::Result<()> {
         with_std_fd(abi::FD_STDOUT, |fd| fd.flush())
     }
 }
 
 impl Stderr {
     pub fn new() -> io::Result<Stderr> { Ok(Stderr(())) }
-
-    pub fn write(&self, data: &[u8]) -> io::Result<usize> {
-        with_std_fd(abi::FD_STDERR, |fd| fd.write(data))
-    }
-
-    pub fn flush(&self) -> io::Result<()> {
-        with_std_fd(abi::FD_STDERR, |fd| fd.flush())
-    }
 }
 
-// FIXME: right now this raw stderr handle is used in a few places because
-//        std::io::stderr_raw isn't exposed, but once that's exposed this impl
-//        should go away
 impl io::Write for Stderr {
-    fn write(&mut self, data: &[u8]) -> io::Result<usize> {
-        Stderr::write(self, data)
+    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
+        with_std_fd(abi::FD_STDERR, |fd| fd.write(buf))
     }
 
     fn flush(&mut self) -> io::Result<()> {
-        Stderr::flush(self)
+        with_std_fd(abi::FD_STDERR, |fd| fd.flush())
     }
 }
 

src/libstd/sys/unix/stdio.rs

@@ -8,55 +8,48 @@ pub struct Stderr(());
 
 impl Stdin {
     pub fn new() -> io::Result<Stdin> { Ok(Stdin(())) }
+}
 
-    pub fn read(&self, data: &mut [u8]) -> io::Result<usize> {
+impl io::Read for Stdin {
+    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
         let fd = FileDesc::new(libc::STDIN_FILENO);
-        let ret = fd.read(data);
+        let ret = fd.read(buf);
         fd.into_raw(); // do not close this FD
         ret
     }
 }
 
 impl Stdout {
     pub fn new() -> io::Result<Stdout> { Ok(Stdout(())) }
+}
 
-    pub fn write(&self, data: &[u8]) -> io::Result<usize> {
+impl io::Write for Stdout {
+    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
         let fd = FileDesc::new(libc::STDOUT_FILENO);
-        let ret = fd.write(data);
+        let ret = fd.write(buf);
         fd.into_raw(); // do not close this FD
         ret
     }
 
-    pub fn flush(&self) -> io::Result<()> {
+    fn flush(&mut self) -> io::Result<()> {
         Ok(())
     }
 }
 
 impl Stderr {
     pub fn new() -> io::Result<Stderr> { Ok(Stderr(())) }
+}
 
-    pub fn write(&self, data: &[u8]) -> io::Result<usize> {
+impl io::Write for Stderr {
+    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
         let fd = FileDesc::new(libc::STDERR_FILENO);
-        let ret = fd.write(data);
+        let ret = fd.write(buf);
         fd.into_raw(); // do not close this FD
         ret
     }
 
-    pub fn flush(&self) -> io::Result<()> {
-        Ok(())
-    }
-}
-
-// FIXME: right now this raw stderr handle is used in a few places because
-//        std::io::stderr_raw isn't exposed, but once that's exposed this impl
-//        should go away
-impl io::Write for Stderr {
-    fn write(&mut self, data: &[u8]) -> io::Result<usize> {
-        Stderr::write(self, data)
-    }
-
     fn flush(&mut self) -> io::Result<()> {
-        Stderr::flush(self)
+        Ok(())
     }
 }
 
@@ -67,5 +60,5 @@ pub fn is_ebadf(err: &io::Error) -> bool {
 pub const STDIN_BUF_SIZE: usize = ::sys_common::io::DEFAULT_BUF_SIZE;
 
 pub fn panic_output() -> Option<impl io::Write> {
-    Stderr::new().ok()
+    io::stderr_raw().ok()
 }

src/libstd/sys/wasm/stdio.rs

@@ -9,23 +9,27 @@ impl Stdin {
     pub fn new() -> io::Result<Stdin> {
         Ok(Stdin)
     }
+}
 
-    pub fn read(&self, data: &mut [u8]) -> io::Result<usize> {
-        Ok(ReadSysCall::perform(0, data))
+impl io::Read for Stdin {
+    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
+        Ok(ReadSysCall::perform(0, buf))
     }
 }
 
 impl Stdout {
     pub fn new() -> io::Result<Stdout> {
         Ok(Stdout)
     }
+}
 
-    pub fn write(&self, data: &[u8]) -> io::Result<usize> {
-        WriteSysCall::perform(1, data);
-        Ok(data.len())
+impl io::Write for Stdout {
+    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
+        WriteSysCall::perform(1, buf);
+        Ok(buf.len())
     }
 
-    pub fn flush(&self) -> io::Result<()> {
+    fn flush(&mut self) -> io::Result<()> {
         Ok(())
     }
 }
@@ -34,23 +38,16 @@ impl Stderr {
     pub fn new() -> io::Result<Stderr> {
         Ok(Stderr)
     }
-
-    pub fn write(&self, data: &[u8]) -> io::Result<usize> {
-        WriteSysCall::perform(2, data);
-        Ok(data.len())
-    }
-
-    pub fn flush(&self) -> io::Result<()> {
-        Ok(())
-    }
 }
 
 impl io::Write for Stderr {
-    fn write(&mut self, data: &[u8]) -> io::Result<usize> {
-        (&*self).write(data)
+    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
+        WriteSysCall::perform(2, buf);
+        Ok(buf.len())
     }
+
     fn flush(&mut self) -> io::Result<()> {
-        (&*self).flush()
+        Ok(())
     }
 }
 
@@ -62,7 +59,7 @@ pub fn is_ebadf(_err: &io::Error) -> bool {
 
 pub fn panic_output() -> Option<impl io::Write> {
     if cfg!(feature = "wasm_syscall") {
-        Stderr::new().ok()
+        io::stderr_raw().ok()
     } else {
         None
     }

src/libstd/sys/windows/process.rs

@@ -252,9 +252,9 @@ impl Stdio {
             // should still be unavailable so propagate the
             // INVALID_HANDLE_VALUE.
             Stdio::Inherit => {
-                match stdio::get(stdio_id) {
+                match stdio::get_handle(stdio_id) {
                     Ok(io) => {
-                        let io = Handle::new(io.handle());
+                        let io = Handle::new(io);
                         let ret = io.duplicate(0, true,
                                                c::DUPLICATE_SAME_ACCESS);
                         io.into_raw();