1 files changed, 87 insertions, 0 deletions
diff --git a/library/std/src/sys/windows/stdio_uwp.rs b/library/std/src/sys/windows/stdio_uwp.rs
new file mode 100644
index 000000000..32550f796
--- /dev/null
+++ b/library/std/src/sys/windows/stdio_uwp.rs
@@ -0,0 +1,87 @@
+#![unstable(issue = "none", feature = "windows_stdio")]
+
+use crate::io;
+use crate::mem::ManuallyDrop;
+use crate::os::windows::io::FromRawHandle;
+use crate::sys::c;
+use crate::sys::handle::Handle;
+
+pub struct Stdin {}
+pub struct Stdout;
+pub struct Stderr;
+
+const MAX_BUFFER_SIZE: usize = 8192;
+pub const STDIN_BUF_SIZE: usize = MAX_BUFFER_SIZE / 2 * 3;
+
+pub fn get_handle(handle_id: c::DWORD) -> io::Result<c::HANDLE> {
+    let handle = unsafe { c::GetStdHandle(handle_id) };
+    if handle == c::INVALID_HANDLE_VALUE {
+        Err(io::Error::last_os_error())
+    } else if handle.is_null() {
+        Err(io::Error::from_raw_os_error(c::ERROR_INVALID_HANDLE as i32))
+    } else {
+        Ok(handle)
+    }
+}
+
+fn write(handle_id: c::DWORD, data: &[u8]) -> io::Result<usize> {
+    let handle = get_handle(handle_id)?;
+    // SAFETY: The handle returned from `get_handle` must be valid and non-null.
+    let handle = unsafe { Handle::from_raw_handle(handle) };
+    ManuallyDrop::new(handle).write(data)
+}
+
+impl Stdin {
+    pub const fn new() -> Stdin {
+        Stdin {}
+    }
+}
+
+impl io::Read for Stdin {
+    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
+        let handle = get_handle(c::STD_INPUT_HANDLE)?;
+        // SAFETY: The handle returned from `get_handle` must be valid and non-null.
+        let handle = unsafe { Handle::from_raw_handle(handle) };
+        ManuallyDrop::new(handle).read(buf)
+    }
+}
+
+impl Stdout {
+    pub const fn new() -> Stdout {
+        Stdout
+    }
+}
+
+impl io::Write for Stdout {
+    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
+        write(c::STD_OUTPUT_HANDLE, buf)
+    }
+
+    fn flush(&mut self) -> io::Result<()> {
+        Ok(())
+    }
+}
+
+impl Stderr {
+    pub const fn new() -> Stderr {
+        Stderr
+    }
+}
+
+impl io::Write for Stderr {
+    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
+        write(c::STD_ERROR_HANDLE, buf)
+    }
+
+    fn flush(&mut self) -> io::Result<()> {
+        Ok(())
+    }
+}
+
+pub fn is_ebadf(err: &io::Error) -> bool {
+    err.raw_os_error() == Some(c::ERROR_INVALID_HANDLE as i32)
+}
+
+pub fn panic_output() -> Option<impl io::Write> {
+    Some(Stderr::new())
+}