std: Add IntoRaw{Fd,Handle,Socket} traits

This commit is an implementation of [RFC 1174][rfc] which adds three new traits
to the standard library:

* `IntoRawFd` - implemented on Unix for all I/O types (files, sockets, etc)
* `IntoRawHandle` - implemented on Windows for files, processes, etc
* `IntoRawSocket` - implemented on Windows for networking types

[rfc]: https://github.com/rust-lang/rfcs/blob/master/text/1174-into-raw-fd-socket-handle-traits.md

Closes #27062

2 files changed, 15 insertions, 3 deletions

diff --git a/src/libstd/net/tcp.rs b/src/libstd/net/tcp.rs
index 66c8403b268..c410233df92 100644
--- a/src/libstd/net/tcp.rs
+++ b/src/libstd/net/tcp.rs
@@ -17,9 +17,9 @@ use io::prelude::*;
 use fmt;
 use io;
 use net::{ToSocketAddrs, SocketAddr, Shutdown};
-use sys_common::net as net_imp;
-use sys_common::{AsInner, FromInner};
 use sys_common::io::read_to_end_uninitialized;
+use sys_common::net as net_imp;
+use sys_common::{AsInner, FromInner, IntoInner};
 use time::Duration;
 
 /// A structure which represents a TCP stream between a local socket and a
@@ -220,6 +220,10 @@ impl FromInner<net_imp::TcpStream> for TcpStream {
     fn from_inner(inner: net_imp::TcpStream) -> TcpStream { TcpStream(inner) }
 }
 
+impl IntoInner<net_imp::TcpStream> for TcpStream {
+    fn into_inner(self) -> net_imp::TcpStream { self.0 }
+}
+
 impl fmt::Debug for TcpStream {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         self.0.fmt(f)
@@ -298,6 +302,10 @@ impl FromInner<net_imp::TcpListener> for TcpListener {
     }
 }
 
+impl IntoInner<net_imp::TcpListener> for TcpListener {
+    fn into_inner(self) -> net_imp::TcpListener { self.0 }
+}
+
 impl fmt::Debug for TcpListener {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         self.0.fmt(f)
diff --git a/src/libstd/net/udp.rs b/src/libstd/net/udp.rs
index 0545175d9ae..a98ccc38735 100644
--- a/src/libstd/net/udp.rs
+++ b/src/libstd/net/udp.rs
@@ -17,7 +17,7 @@ use fmt;
 use io::{self, Error, ErrorKind};
 use net::{ToSocketAddrs, SocketAddr, IpAddr};
 use sys_common::net as net_imp;
-use sys_common::{AsInner, FromInner};
+use sys_common::{AsInner, FromInner, IntoInner};
 use time::Duration;
 
 /// A User Datagram Protocol socket.
@@ -174,6 +174,10 @@ impl FromInner<net_imp::UdpSocket> for UdpSocket {
     fn from_inner(inner: net_imp::UdpSocket) -> UdpSocket { UdpSocket(inner) }
 }
 
+impl IntoInner<net_imp::UdpSocket> for UdpSocket {
+    fn into_inner(self) -> net_imp::UdpSocket { self.0 }
+}
+
 impl fmt::Debug for UdpSocket {
     fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
         self.0.fmt(f)