src/libstd/sys/unix/ext/io.rs

   1 // Copyright 2015 The Rust Project Developers. See the COPYRIGHT
   2 // file at the top-level directory of this distribution and at
   3 // http://rust-lang.org/COPYRIGHT.
   4 //
   5 // Licensed under the Apache License, Version 2.0 <LICENSE-APACHE or
   6 // http://www.apache.org/licenses/LICENSE-2.0> or the MIT license
   7 // <LICENSE-MIT or http://opensource.org/licenses/MIT>, at your
   8 // option. This file may not be copied, modified, or distributed
   9 // except according to those terms.
  10
  11 //! Unix-specific extensions to general I/O primitives
  12
  13 #![stable(feature = "rust1", since = "1.0.0")]
  14
  15 use fs;
  16 use net;
  17 use os::raw;
  18 use sys;
  19 use sys_common::{self, AsInner, FromInner, IntoInner};
  20
  21 /// Raw file descriptors.
  22 #[stable(feature = "rust1", since = "1.0.0")]
  23 pub type RawFd = raw::c_int;
  24
  25 /// A trait to extract the raw unix file descriptor from an underlying
  26 /// object.
  27 ///
  28 /// This is only available on unix platforms and must be imported in order
  29 /// to call the method. Windows platforms have a corresponding `AsRawHandle`
  30 /// and `AsRawSocket` set of traits.
  31 #[stable(feature = "rust1", since = "1.0.0")]
  32 pub trait AsRawFd {
  33     /// Extracts the raw file descriptor.
  34     ///
  35     /// This method does **not** pass ownership of the raw file descriptor
  36     /// to the caller. The descriptor is only guarantee to be valid while
  37     /// the original object has not yet been destroyed.
  38     #[stable(feature = "rust1", since = "1.0.0")]
  39     fn as_raw_fd(&self) -> RawFd;
  40 }
  41
  42 /// A trait to express the ability to construct an object from a raw file
  43 /// descriptor.
  44 #[stable(feature = "from_raw_os", since = "1.1.0")]
  45 pub trait FromRawFd {
  46     /// Constructs a new instances of `Self` from the given raw file
  47     /// descriptor.
  48     ///
  49     /// This function **consumes ownership** of the specified file
  50     /// descriptor. The returned object will take responsibility for closing
  51     /// it when the object goes out of scope.
  52     ///
  53     /// This function is also unsafe as the primitives currently returned
  54     /// have the contract that they are the sole owner of the file
  55     /// descriptor they are wrapping. Usage of this function could
  56     /// accidentally allow violating this contract which can cause memory
  57     /// unsafety in code that relies on it being true.
  58     #[stable(feature = "from_raw_os", since = "1.1.0")]
  59     unsafe fn from_raw_fd(fd: RawFd) -> Self;
  60 }
  61
  62 /// A trait to express the ability to consume an object and acquire ownership of
  63 /// its raw file descriptor.
  64 #[unstable(feature = "into_raw_os", reason = "recently added API")]
  65 pub trait IntoRawFd {
  66     /// Consumes this object, returning the raw underlying file descriptor.
  67     ///
  68     /// This function **transfers ownership** of the underlying file descriptor
  69     /// to the caller. Callers are then the unique owners of the file descriptor
  70     /// and must close the descriptor once it's no longer needed.
  71     fn into_raw_fd(self) -> RawFd;
  72 }
  73
  74 #[stable(feature = "rust1", since = "1.0.0")]
  75 impl AsRawFd for fs::File {
  76     fn as_raw_fd(&self) -> RawFd {
  77         self.as_inner().fd().raw()
  78     }
  79 }
  80 #[stable(feature = "from_raw_os", since = "1.1.0")]
  81 impl FromRawFd for fs::File {
  82     unsafe fn from_raw_fd(fd: RawFd) -> fs::File {
  83         fs::File::from_inner(sys::fs::File::from_inner(fd))
  84     }
  85 }
  86 impl IntoRawFd for fs::File {
  87     fn into_raw_fd(self) -> RawFd {
  88         self.into_inner().into_fd().into_raw()
  89     }
  90 }
  91
  92 #[stable(feature = "rust1", since = "1.0.0")]
  93 impl AsRawFd for net::TcpStream {
  94     fn as_raw_fd(&self) -> RawFd { *self.as_inner().socket().as_inner() }
  95 }
  96 #[stable(feature = "rust1", since = "1.0.0")]
  97 impl AsRawFd for net::TcpListener {
  98     fn as_raw_fd(&self) -> RawFd { *self.as_inner().socket().as_inner() }
  99 }
 100 #[stable(feature = "rust1", since = "1.0.0")]
 101 impl AsRawFd for net::UdpSocket {
 102     fn as_raw_fd(&self) -> RawFd { *self.as_inner().socket().as_inner() }
 103 }
 104
 105 #[stable(feature = "from_raw_os", since = "1.1.0")]
 106 impl FromRawFd for net::TcpStream {
 107     unsafe fn from_raw_fd(fd: RawFd) -> net::TcpStream {
 108         let socket = sys::net::Socket::from_inner(fd);
 109         net::TcpStream::from_inner(sys_common::net::TcpStream::from_inner(socket))
 110     }
 111 }
 112 #[stable(feature = "from_raw_os", since = "1.1.0")]
 113 impl FromRawFd for net::TcpListener {
 114     unsafe fn from_raw_fd(fd: RawFd) -> net::TcpListener {
 115         let socket = sys::net::Socket::from_inner(fd);
 116         net::TcpListener::from_inner(sys_common::net::TcpListener::from_inner(socket))
 117     }
 118 }
 119 #[stable(feature = "from_raw_os", since = "1.1.0")]
 120 impl FromRawFd for net::UdpSocket {
 121     unsafe fn from_raw_fd(fd: RawFd) -> net::UdpSocket {
 122         let socket = sys::net::Socket::from_inner(fd);
 123         net::UdpSocket::from_inner(sys_common::net::UdpSocket::from_inner(socket))
 124     }
 125 }
 126
 127 impl IntoRawFd for net::TcpStream {
 128     fn into_raw_fd(self) -> RawFd {
 129         self.into_inner().into_socket().into_inner()
 130     }
 131 }
 132 impl IntoRawFd for net::TcpListener {
 133     fn into_raw_fd(self) -> RawFd {
 134         self.into_inner().into_socket().into_inner()
 135     }
 136 }
 137 impl IntoRawFd for net::UdpSocket {
 138     fn into_raw_fd(self) -> RawFd {
 139         self.into_inner().into_socket().into_inner()
 140     }
 141 }