rollup merge of #21835: alexcrichton/iov2

This commit is an implementation of [RFC 576][rfc] which adds back the `std::io`
module to the standard library. No functionality in `std::old_io` has been
deprecated just yet, and the new `std::io` module is behind the same `io`
feature gate.

[rfc]: https://github.com/rust-lang/rfcs/pull/576

A good bit of functionality was copied over from `std::old_io`, but many tweaks
were required for the new method signatures. Behavior such as precisely when
buffered objects call to the underlying object may have been tweaked slightly in
the transition. All implementations were audited to use composition wherever
possible. For example the custom `pos` and `cap` cursors in `BufReader` were
removed in favor of just using `Cursor<Vec<u8>>`.

A few liberties were taken during this implementation which were not explicitly
spelled out in the RFC:

* The old `LineBufferedWriter` is now named `LineWriter`
* The internal representation of `Error` now favors OS error codes (a
  0-allocation path) and contains a `Box` for extra semantic data.
* The io prelude currently reexports `Seek` as `NewSeek` to prevent conflicts
  with the real prelude reexport of `old_io::Seek`
* The `chars` method was moved from `BufReadExt` to `ReadExt`.
* The `chars` iterator returns a custom error with a variant that explains that
  the data was not valid UTF-8.

1 files changed, 29 insertions, 0 deletions

diff --git a/src/libstd/sys/windows/mod.rs b/src/libstd/sys/windows/mod.rs
index 8dd467eba9e..f1af70e2cf7 100644
--- a/src/libstd/sys/windows/mod.rs
+++ b/src/libstd/sys/windows/mod.rs
@@ -15,6 +15,7 @@
 use prelude::v1::*;
 
 use ffi::OsStr;
+use io::ErrorKind;
 use libc;
 use mem;
 use old_io::{self, IoResult, IoError};
@@ -143,6 +144,34 @@ pub fn decode_error_detailed(errno: i32) -> IoError {
     err
 }
 
+pub fn decode_error_kind(errno: i32) -> ErrorKind {
+    match errno as libc::c_int {
+        libc::ERROR_ACCESS_DENIED => ErrorKind::PermissionDenied,
+        libc::ERROR_ALREADY_EXISTS => ErrorKind::PathAlreadyExists,
+        libc::ERROR_BROKEN_PIPE => ErrorKind::BrokenPipe,
+        libc::ERROR_FILE_NOT_FOUND => ErrorKind::FileNotFound,
+        libc::ERROR_INVALID_FUNCTION => ErrorKind::InvalidInput,
+        libc::ERROR_INVALID_HANDLE => ErrorKind::MismatchedFileTypeForOperation,
+        libc::ERROR_INVALID_NAME => ErrorKind::InvalidInput,
+        libc::ERROR_NOTHING_TO_TERMINATE => ErrorKind::InvalidInput,
+        libc::ERROR_NO_DATA => ErrorKind::BrokenPipe,
+        libc::ERROR_OPERATION_ABORTED => ErrorKind::TimedOut,
+
+        libc::WSAEACCES => ErrorKind::PermissionDenied,
+        libc::WSAEADDRINUSE => ErrorKind::ConnectionRefused,
+        libc::WSAEADDRNOTAVAIL => ErrorKind::ConnectionRefused,
+        libc::WSAECONNABORTED => ErrorKind::ConnectionAborted,
+        libc::WSAECONNREFUSED => ErrorKind::ConnectionRefused,
+        libc::WSAECONNRESET => ErrorKind::ConnectionReset,
+        libc::WSAEINVAL => ErrorKind::InvalidInput,
+        libc::WSAENOTCONN => ErrorKind::NotConnected,
+        libc::WSAEWOULDBLOCK => ErrorKind::ResourceUnavailable,
+
+        _ => ErrorKind::Other,
+    }
+}
+
+
 #[inline]
 pub fn retry<I, F>(f: F) -> I where F: FnOnce() -> I { f() } // PR rust-lang/rust/#17020