library/std/src/os/windows/io.rs

//! Windows-specific extensions to general I/O primitives.

#![stable(feature = "rust1", since = "1.0.0")]

use crate::fs;
use crate::io;
use crate::net;
use crate::os::windows::raw;
use crate::sys;
use crate::sys::c;
use crate::sys_common::{self, AsInner, FromInner, IntoInner};

/// Raw HANDLEs.
#[stable(feature = "rust1", since = "1.0.0")]
pub type RawHandle = raw::HANDLE;

/// Raw SOCKETs.
#[stable(feature = "rust1", since = "1.0.0")]
pub type RawSocket = raw::SOCKET;

/// Extracts raw handles.
#[stable(feature = "rust1", since = "1.0.0")]
pub trait AsRawHandle {
    /// Extracts the raw handle, without taking any ownership.
    #[stable(feature = "rust1", since = "1.0.0")]
    fn as_raw_handle(&self) -> RawHandle;
}

/// Construct I/O objects from raw handles.
#[stable(feature = "from_raw_os", since = "1.1.0")]
pub trait FromRawHandle {
    /// Constructs a new I/O object from the specified raw handle.
    ///
    /// This function will **consume ownership** of the handle given,
    /// passing responsibility for closing the handle to the returned
    /// object.
    ///
    /// This function is also unsafe as the primitives currently returned
    /// have the contract that they are the sole owner of the file
    /// descriptor they are wrapping. Usage of this function could
    /// accidentally allow violating this contract which can cause memory
    /// unsafety in code that relies on it being true.
    #[stable(feature = "from_raw_os", since = "1.1.0")]
    unsafe fn from_raw_handle(handle: RawHandle) -> Self;
}

/// A trait to express the ability to consume an object and acquire ownership of
/// its raw `HANDLE`.
#[stable(feature = "into_raw_os", since = "1.4.0")]
pub trait IntoRawHandle {
    /// Consumes this object, returning the raw underlying handle.
    ///
    /// This function **transfers ownership** of the underlying handle to the
    /// caller. Callers are then the unique owners of the handle and must close
    /// it once it's no longer needed.
    #[stable(feature = "into_raw_os", since = "1.4.0")]
    fn into_raw_handle(self) -> RawHandle;
}

#[stable(feature = "rust1", since = "1.0.0")]
impl AsRawHandle for fs::File {
    #[inline]
    fn as_raw_handle(&self) -> RawHandle {
        self.as_inner().handle().raw() as RawHandle
    }
}

#[stable(feature = "asraw_stdio", since = "1.21.0")]
impl AsRawHandle for io::Stdin {
    fn as_raw_handle(&self) -> RawHandle {
        unsafe { c::GetStdHandle(c::STD_INPUT_HANDLE) as RawHandle }
    }
}

#[stable(feature = "asraw_stdio", since = "1.21.0")]
impl AsRawHandle for io::Stdout {
    fn as_raw_handle(&self) -> RawHandle {
        unsafe { c::GetStdHandle(c::STD_OUTPUT_HANDLE) as RawHandle }
    }
}

#[stable(feature = "asraw_stdio", since = "1.21.0")]
impl AsRawHandle for io::Stderr {
    fn as_raw_handle(&self) -> RawHandle {
        unsafe { c::GetStdHandle(c::STD_ERROR_HANDLE) as RawHandle }
    }
}

#[stable(feature = "asraw_stdio_locks", since = "1.35.0")]
impl<'a> AsRawHandle for io::StdinLock<'a> {
    fn as_raw_handle(&self) -> RawHandle {
        unsafe { c::GetStdHandle(c::STD_INPUT_HANDLE) as RawHandle }
    }
}

#[stable(feature = "asraw_stdio_locks", since = "1.35.0")]
impl<'a> AsRawHandle for io::StdoutLock<'a> {
    fn as_raw_handle(&self) -> RawHandle {
        unsafe { c::GetStdHandle(c::STD_OUTPUT_HANDLE) as RawHandle }
    }
}

#[stable(feature = "asraw_stdio_locks", since = "1.35.0")]
impl<'a> AsRawHandle for io::StderrLock<'a> {
    fn as_raw_handle(&self) -> RawHandle {
        unsafe { c::GetStdHandle(c::STD_ERROR_HANDLE) as RawHandle }
    }
}

#[stable(feature = "from_raw_os", since = "1.1.0")]
impl FromRawHandle for fs::File {
    #[inline]
    unsafe fn from_raw_handle(handle: RawHandle) -> fs::File {
        let handle = handle as c::HANDLE;
        fs::File::from_inner(sys::fs::File::from_inner(handle))
    }
}

#[stable(feature = "into_raw_os", since = "1.4.0")]
impl IntoRawHandle for fs::File {
    #[inline]
    fn into_raw_handle(self) -> RawHandle {
        self.into_inner().into_handle().into_raw() as *mut _
    }
}

/// Extracts raw sockets.
#[stable(feature = "rust1", since = "1.0.0")]
pub trait AsRawSocket {
    /// Extracts the underlying raw socket from this object.
    #[stable(feature = "rust1", since = "1.0.0")]
    fn as_raw_socket(&self) -> RawSocket;
}

/// Creates I/O objects from raw sockets.
#[stable(feature = "from_raw_os", since = "1.1.0")]
pub trait FromRawSocket {
    /// Creates a new I/O object from the given raw socket.
    ///
    /// This function will **consume ownership** of the socket provided and
    /// it will be closed when the returned object goes out of scope.
    ///
    /// This function is also unsafe as the primitives currently returned
    /// have the contract that they are the sole owner of the file
    /// descriptor they are wrapping. Usage of this function could
    /// accidentally allow violating this contract which can cause memory
    /// unsafety in code that relies on it being true.
    #[stable(feature = "from_raw_os", since = "1.1.0")]
    unsafe fn from_raw_socket(sock: RawSocket) -> Self;
}

/// A trait to express the ability to consume an object and acquire ownership of
/// its raw `SOCKET`.
#[stable(feature = "into_raw_os", since = "1.4.0")]
pub trait IntoRawSocket {
    /// Consumes this object, returning the raw underlying socket.
    ///
    /// This function **transfers ownership** of the underlying socket to the
    /// caller. Callers are then the unique owners of the socket and must close
    /// it once it's no longer needed.
    #[stable(feature = "into_raw_os", since = "1.4.0")]
    fn into_raw_socket(self) -> RawSocket;
}

#[stable(feature = "rust1", since = "1.0.0")]
impl AsRawSocket for net::TcpStream {
    #[inline]
    fn as_raw_socket(&self) -> RawSocket {
        *self.as_inner().socket().as_inner()
    }
}
#[stable(feature = "rust1", since = "1.0.0")]
impl AsRawSocket for net::TcpListener {
    #[inline]
    fn as_raw_socket(&self) -> RawSocket {
        *self.as_inner().socket().as_inner()
    }
}
#[stable(feature = "rust1", since = "1.0.0")]
impl AsRawSocket for net::UdpSocket {
    #[inline]
    fn as_raw_socket(&self) -> RawSocket {
        *self.as_inner().socket().as_inner()
    }
}

#[stable(feature = "from_raw_os", since = "1.1.0")]
impl FromRawSocket for net::TcpStream {
    #[inline]
    unsafe fn from_raw_socket(sock: RawSocket) -> net::TcpStream {
        let sock = sys::net::Socket::from_inner(sock);
        net::TcpStream::from_inner(sys_common::net::TcpStream::from_inner(sock))
    }
}
#[stable(feature = "from_raw_os", since = "1.1.0")]
impl FromRawSocket for net::TcpListener {
    #[inline]
    unsafe fn from_raw_socket(sock: RawSocket) -> net::TcpListener {
        let sock = sys::net::Socket::from_inner(sock);
        net::TcpListener::from_inner(sys_common::net::TcpListener::from_inner(sock))
    }
}
#[stable(feature = "from_raw_os", since = "1.1.0")]
impl FromRawSocket for net::UdpSocket {
    #[inline]
    unsafe fn from_raw_socket(sock: RawSocket) -> net::UdpSocket {
        let sock = sys::net::Socket::from_inner(sock);
        net::UdpSocket::from_inner(sys_common::net::UdpSocket::from_inner(sock))
    }
}

#[stable(feature = "into_raw_os", since = "1.4.0")]
impl IntoRawSocket for net::TcpStream {
    #[inline]
    fn into_raw_socket(self) -> RawSocket {
        self.into_inner().into_socket().into_inner()
    }
}

#[stable(feature = "into_raw_os", since = "1.4.0")]
impl IntoRawSocket for net::TcpListener {
    #[inline]
    fn into_raw_socket(self) -> RawSocket {
        self.into_inner().into_socket().into_inner()
    }
}

#[stable(feature = "into_raw_os", since = "1.4.0")]
impl IntoRawSocket for net::UdpSocket {
    #[inline]
    fn into_raw_socket(self) -> RawSocket {
        self.into_inner().into_socket().into_inner()
    }
}