library/std/src/sys/net/connection/socket/windows.rs - rust - Git at Google

 #![unstable(issue = "none", feature = "windows_net")]

 use core::ffi::{c_int, c_long, c_ulong, c_ushort};

 use super::{getsockopt, setsockopt, socket_addr_from_c, socket_addr_to_c};
 use crate::io::{self, BorrowedBuf, BorrowedCursor, IoSlice, IoSliceMut, Read};
 use crate::net::{Shutdown, SocketAddr};
 use crate::os::windows::io::{
     AsRawSocket, AsSocket, BorrowedSocket, FromRawSocket, IntoRawSocket, OwnedSocket, RawSocket,
 };
 use crate::sync::atomic::Atomic;
 use crate::sync::atomic::Ordering::{AcqRel, Relaxed};
 use crate::sys::c;
 use crate::sys_common::{AsInner, FromInner, IntoInner};
 use crate::time::Duration;
 use crate::{cmp, mem, ptr, sys};

 #[allow(non_camel_case_types)]
 pub type wrlen_t = i32;

 pub(super) mod netc {
     //! BSD socket compatibility shim
     //!
     //! Some Windows API types are not quite what's expected by our cross-platform
     //! net code. E.g. naming differences or different pointer types.

     use core::ffi::{c_char, c_int, c_uint, c_ulong, c_ushort, c_void};

     use crate::sys::c::{self, ADDRESS_FAMILY, ADDRINFOA, SOCKADDR, SOCKET};
     // re-exports from Windows API bindings.
     pub use crate::sys::c::{
         ADDRESS_FAMILY as sa_family_t, ADDRINFOA as addrinfo, IP_ADD_MEMBERSHIP,
         IP_DROP_MEMBERSHIP, IP_MULTICAST_LOOP, IP_MULTICAST_TTL, IP_TTL, IPPROTO_IP, IPPROTO_IPV6,
         IPV6_ADD_MEMBERSHIP, IPV6_DROP_MEMBERSHIP, IPV6_MULTICAST_LOOP, IPV6_V6ONLY, SO_BROADCAST,
         SO_RCVTIMEO, SO_SNDTIMEO, SOCK_DGRAM, SOCK_STREAM, SOCKADDR as sockaddr,
         SOCKADDR_STORAGE as sockaddr_storage, SOL_SOCKET, bind, connect, freeaddrinfo, getpeername,
         getsockname, getsockopt, listen, setsockopt,
     };

     #[allow(non_camel_case_types)]
     pub type socklen_t = c_int;

     pub const AF_INET: i32 = c::AF_INET as i32;
     pub const AF_INET6: i32 = c::AF_INET6 as i32;

     // The following two structs use a union in the generated bindings but
     // our cross-platform code expects a normal field so it's redefined here.
     // As a consequence, we also need to redefine other structs that use this struct.
     #[repr(C)]
     #[derive(Copy, Clone)]
     pub struct in_addr {
         pub s_addr: u32,
     }

     #[repr(C)]
     #[derive(Copy, Clone)]
     pub struct in6_addr {
         pub s6_addr: [u8; 16],
     }

     #[repr(C)]
     pub struct ip_mreq {
         pub imr_multiaddr: in_addr,
         pub imr_interface: in_addr,
     }

     #[repr(C)]
     pub struct ipv6_mreq {
         pub ipv6mr_multiaddr: in6_addr,
         pub ipv6mr_interface: c_uint,
     }

     #[repr(C)]
     #[derive(Copy, Clone)]
     pub struct sockaddr_in {
         pub sin_family: ADDRESS_FAMILY,
         pub sin_port: c_ushort,
         pub sin_addr: in_addr,
         pub sin_zero: [c_char; 8],
     }

     #[repr(C)]
     #[derive(Copy, Clone)]
     pub struct sockaddr_in6 {
         pub sin6_family: ADDRESS_FAMILY,
         pub sin6_port: c_ushort,
         pub sin6_flowinfo: c_ulong,
         pub sin6_addr: in6_addr,
         pub sin6_scope_id: c_ulong,
     }

     pub unsafe fn send(socket: SOCKET, buf: *const c_void, len: c_int, flags: c_int) -> c_int {
         unsafe { c::send(socket, buf.cast::<u8>(), len, flags) }
     }
     pub unsafe fn sendto(
         socket: SOCKET,
         buf: *const c_void,
         len: c_int,
         flags: c_int,
         addr: *const SOCKADDR,
         addrlen: c_int,
     ) -> c_int {
         unsafe { c::sendto(socket, buf.cast::<u8>(), len, flags, addr, addrlen) }
     }
     pub unsafe fn getaddrinfo(
         node: *const c_char,
         service: *const c_char,
         hints: *const ADDRINFOA,
         res: *mut *mut ADDRINFOA,
     ) -> c_int {
         unsafe { c::getaddrinfo(node.cast::<u8>(), service.cast::<u8>(), hints, res) }
     }
 }

 #[expect(missing_debug_implementations)]
 pub struct Socket(OwnedSocket);

 static WSA_INITIALIZED: Atomic<bool> = Atomic::<bool>::new(false);

 /// Checks whether the Windows socket interface has been started already, and
 /// if not, starts it.
 #[inline]
 pub fn init() {
     if !WSA_INITIALIZED.load(Relaxed) {
         wsa_startup();
     }
 }

 #[cold]
 fn wsa_startup() {
     unsafe {
         let mut data: c::WSADATA = mem::zeroed();
         let ret = c::WSAStartup(
             0x202, // version 2.2
             &mut data,
         );
         assert_eq!(ret, 0);
         if WSA_INITIALIZED.swap(true, AcqRel) {
             // If another thread raced with us and called WSAStartup first then call
             // WSACleanup so it's as though WSAStartup was only called once.
             c::WSACleanup();
         }
     }
 }

 pub fn cleanup() {
     // We don't need to call WSACleanup here because exiting the process will cause
     // the OS to clean everything for us, which is faster than doing it manually.
     // See #141799.
 }

 /// Returns the last error from the Windows socket interface.
 fn last_error() -> io::Error {
     io::Error::from_raw_os_error(unsafe { c::WSAGetLastError() })
 }

 #[doc(hidden)]
 pub trait IsMinusOne {
     fn is_minus_one(&self) -> bool;
 }

 macro_rules! impl_is_minus_one {
     ($($t:ident)*) => ($(impl IsMinusOne for $t {
         fn is_minus_one(&self) -> bool {
             *self == -1
         }
     })*)
 }

 impl_is_minus_one! { i8 i16 i32 i64 isize }

 /// Checks if the signed integer is the Windows constant `SOCKET_ERROR` (-1)
 /// and if so, returns the last error from the Windows socket interface. This
 /// function must be called before another call to the socket API is made.
 pub fn cvt<T: IsMinusOne>(t: T) -> io::Result<T> {
     if t.is_minus_one() { Err(last_error()) } else { Ok(t) }
 }

 /// A variant of `cvt` for `getaddrinfo` which return 0 for a success.
 pub fn cvt_gai(err: c_int) -> io::Result<()> {
     if err == 0 { Ok(()) } else { Err(last_error()) }
 }

 /// Just to provide the same interface as sys/pal/unix/net.rs
 pub fn cvt_r<T, F>(mut f: F) -> io::Result<T>
 where
     T: IsMinusOne,
     F: FnMut() -> T,
 {
     cvt(f())
 }

 impl Socket {
     pub fn new(addr: &SocketAddr, ty: c_int) -> io::Result<Socket> {
         let family = match *addr {
             SocketAddr::V4(..) => netc::AF_INET,
             SocketAddr::V6(..) => netc::AF_INET6,
         };
         let socket = unsafe {
             c::WSASocketW(
                 family,
                 ty,
                 0,
                 ptr::null_mut(),
                 0,
                 c::WSA_FLAG_OVERLAPPED | c::WSA_FLAG_NO_HANDLE_INHERIT,
             )
         };

         if socket != c::INVALID_SOCKET {
             unsafe { Ok(Self::from_raw(socket)) }
         } else {
             let error = unsafe { c::WSAGetLastError() };

             if error != c::WSAEPROTOTYPE && error != c::WSAEINVAL {
                 return Err(io::Error::from_raw_os_error(error));
             }

             let socket =
                 unsafe { c::WSASocketW(family, ty, 0, ptr::null_mut(), 0, c::WSA_FLAG_OVERLAPPED) };

             if socket == c::INVALID_SOCKET {
                 return Err(last_error());
             }

             unsafe {
                 let socket = Self::from_raw(socket);
                 socket.0.set_no_inherit()?;
                 Ok(socket)
             }
         }
     }

     pub fn connect(&self, addr: &SocketAddr) -> io::Result<()> {
         let (addr, len) = socket_addr_to_c(addr);
         let result = unsafe { c::connect(self.as_raw(), addr.as_ptr(), len) };
         cvt(result).map(drop)
     }

     pub fn connect_timeout(&self, addr: &SocketAddr, timeout: Duration) -> io::Result<()> {
         self.set_nonblocking(true)?;
         let result = self.connect(addr);
         self.set_nonblocking(false)?;

         match result {
             Err(ref error) if error.kind() == io::ErrorKind::WouldBlock => {
                 if timeout.as_secs() == 0 && timeout.subsec_nanos() == 0 {
                     return Err(io::Error::ZERO_TIMEOUT);
                 }

                 let mut timeout = c::TIMEVAL {
                     tv_sec: cmp::min(timeout.as_secs(), c_long::MAX as u64) as c_long,
                     tv_usec: timeout.subsec_micros() as c_long,
                 };

                 if timeout.tv_sec == 0 && timeout.tv_usec == 0 {
                     timeout.tv_usec = 1;
                 }

                 let fds = {
                     let mut fds = unsafe { mem::zeroed::<c::FD_SET>() };
                     fds.fd_count = 1;
                     fds.fd_array[0] = self.as_raw();
                     fds
                 };

                 let mut writefds = fds;
                 let mut errorfds = fds;

                 let count = {
                     let result = unsafe {
                         c::select(1, ptr::null_mut(), &mut writefds, &mut errorfds, &timeout)
                     };
                     cvt(result)?
                 };

                 match count {
                     0 => Err(io::const_error!(io::ErrorKind::TimedOut, "connection timed out")),
                     _ => {
                         if writefds.fd_count != 1 {
                             if let Some(e) = self.take_error()? {
                                 return Err(e);
                             }
                         }

                         Ok(())
                     }
                 }
             }
             _ => result,
         }
     }

     pub fn accept(&self, storage: *mut c::SOCKADDR, len: *mut c_int) -> io::Result<Socket> {
         let socket = unsafe { c::accept(self.as_raw(), storage, len) };

         match socket {
             c::INVALID_SOCKET => Err(last_error()),
             _ => unsafe { Ok(Self::from_raw(socket)) },
         }
     }

     pub fn duplicate(&self) -> io::Result<Socket> {
         Ok(Self(self.0.try_clone()?))
     }

     fn recv_with_flags(&self, mut buf: BorrowedCursor<'_>, flags: c_int) -> io::Result<()> {
         // On unix when a socket is shut down all further reads return 0, so we
         // do the same on windows to map a shut down socket to returning EOF.
         let length = cmp::min(buf.capacity(), i32::MAX as usize) as i32;
         let result =
             unsafe { c::recv(self.as_raw(), buf.as_mut().as_mut_ptr() as *mut _, length, flags) };

         match result {
             c::SOCKET_ERROR => {
                 let error = unsafe { c::WSAGetLastError() };

                 if error == c::WSAESHUTDOWN {
                     Ok(())
                 } else {
                     Err(io::Error::from_raw_os_error(error))
                 }
             }
             _ => {
                 unsafe { buf.advance_unchecked(result as usize) };
                 Ok(())
             }
         }
     }

     pub fn read(&self, buf: &mut [u8]) -> io::Result<usize> {
         let mut buf = BorrowedBuf::from(buf);
         self.recv_with_flags(buf.unfilled(), 0)?;
         Ok(buf.len())
     }

     pub fn read_buf(&self, buf: BorrowedCursor<'_>) -> io::Result<()> {
         self.recv_with_flags(buf, 0)
     }

     pub fn read_vectored(&self, bufs: &mut [IoSliceMut<'_>]) -> io::Result<usize> {
         // On unix when a socket is shut down all further reads return 0, so we
         // do the same on windows to map a shut down socket to returning EOF.
         let length = cmp::min(bufs.len(), u32::MAX as usize) as u32;
         let mut nread = 0;
         let mut flags = 0;
         let result = unsafe {
             c::WSARecv(
                 self.as_raw(),
                 bufs.as_mut_ptr() as *mut c::WSABUF,
                 length,
                 &mut nread,
                 &mut flags,
                 ptr::null_mut(),
                 None,
             )
         };

         match result {
             0 => Ok(nread as usize),
             _ => {
                 let error = unsafe { c::WSAGetLastError() };

                 if error == c::WSAESHUTDOWN {
                     Ok(0)
                 } else {
                     Err(io::Error::from_raw_os_error(error))
                 }
             }
         }
     }

     #[inline]
     pub fn is_read_vectored(&self) -> bool {
         true
     }

     pub fn peek(&self, buf: &mut [u8]) -> io::Result<usize> {
         let mut buf = BorrowedBuf::from(buf);
         self.recv_with_flags(buf.unfilled(), c::MSG_PEEK)?;
         Ok(buf.len())
     }

     fn recv_from_with_flags(
         &self,
         buf: &mut [u8],
         flags: c_int,
     ) -> io::Result<(usize, SocketAddr)> {
         let mut storage = unsafe { mem::zeroed::<c::SOCKADDR_STORAGE>() };
         let mut addrlen = size_of_val(&storage) as netc::socklen_t;
         let length = cmp::min(buf.len(), <wrlen_t>::MAX as usize) as wrlen_t;

         // On unix when a socket is shut down all further reads return 0, so we
         // do the same on windows to map a shut down socket to returning EOF.
         let result = unsafe {
             c::recvfrom(
                 self.as_raw(),
                 buf.as_mut_ptr() as *mut _,
                 length,
                 flags,
                 (&raw mut storage) as *mut _,
                 &mut addrlen,
             )
         };

         match result {
             c::SOCKET_ERROR => {
                 let error = unsafe { c::WSAGetLastError() };

                 if error == c::WSAESHUTDOWN {
                     Ok((0, unsafe { socket_addr_from_c(&storage, addrlen as usize)? }))
                 } else {
                     Err(io::Error::from_raw_os_error(error))
                 }
             }
             _ => Ok((result as usize, unsafe { socket_addr_from_c(&storage, addrlen as usize)? })),
         }
     }

     pub fn recv_from(&self, buf: &mut [u8]) -> io::Result<(usize, SocketAddr)> {
         self.recv_from_with_flags(buf, 0)
     }

     pub fn peek_from(&self, buf: &mut [u8]) -> io::Result<(usize, SocketAddr)> {
         self.recv_from_with_flags(buf, c::MSG_PEEK)
     }

     pub fn write_vectored(&self, bufs: &[IoSlice<'_>]) -> io::Result<usize> {
         let length = cmp::min(bufs.len(), u32::MAX as usize) as u32;
         let mut nwritten = 0;
         let result = unsafe {
             c::WSASend(
                 self.as_raw(),
                 bufs.as_ptr() as *const c::WSABUF as *mut _,
                 length,
                 &mut nwritten,
                 0,
                 ptr::null_mut(),
                 None,
             )
         };
         cvt(result).map(|_| nwritten as usize)
     }

     #[inline]
     pub fn is_write_vectored(&self) -> bool {
         true
     }

     pub fn set_timeout(&self, dur: Option<Duration>, kind: c_int) -> io::Result<()> {
         let timeout = match dur {
             Some(dur) => {
                 let timeout = sys::dur2timeout(dur);
                 if timeout == 0 {
                     return Err(io::Error::ZERO_TIMEOUT);
                 }
                 timeout
             }
             None => 0,
         };
         setsockopt(self, c::SOL_SOCKET, kind, timeout)
     }

     pub fn timeout(&self, kind: c_int) -> io::Result<Option<Duration>> {
         let raw: u32 = getsockopt(self, c::SOL_SOCKET, kind)?;
         if raw == 0 {
             Ok(None)
         } else {
             let secs = raw / 1000;
             let nsec = (raw % 1000) * 1000000;
             Ok(Some(Duration::new(secs as u64, nsec as u32)))
         }
     }

     pub fn shutdown(&self, how: Shutdown) -> io::Result<()> {
         let how = match how {
             Shutdown::Write => c::SD_SEND,
             Shutdown::Read => c::SD_RECEIVE,
             Shutdown::Both => c::SD_BOTH,
         };
         let result = unsafe { c::shutdown(self.as_raw(), how) };
         cvt(result).map(drop)
     }

     pub fn set_nonblocking(&self, nonblocking: bool) -> io::Result<()> {
         let mut nonblocking = nonblocking as c_ulong;
         let result =
             unsafe { c::ioctlsocket(self.as_raw(), c::FIONBIO as c_int, &mut nonblocking) };
         cvt(result).map(drop)
     }

     pub fn set_linger(&self, linger: Option<Duration>) -> io::Result<()> {
         let linger = c::LINGER {
             l_onoff: linger.is_some() as c_ushort,
             l_linger: linger.unwrap_or_default().as_secs() as c_ushort,
         };

         setsockopt(self, c::SOL_SOCKET, c::SO_LINGER, linger)
     }

     pub fn linger(&self) -> io::Result<Option<Duration>> {
         let val: c::LINGER = getsockopt(self, c::SOL_SOCKET, c::SO_LINGER)?;

         Ok((val.l_onoff != 0).then(|| Duration::from_secs(val.l_linger as u64)))
     }

     pub fn set_nodelay(&self, nodelay: bool) -> io::Result<()> {
         setsockopt(self, c::IPPROTO_TCP, c::TCP_NODELAY, nodelay as c::BOOL)
     }

     pub fn nodelay(&self) -> io::Result<bool> {
         let raw: c::BOOL = getsockopt(self, c::IPPROTO_TCP, c::TCP_NODELAY)?;
         Ok(raw != 0)
     }

     pub fn take_error(&self) -> io::Result<Option<io::Error>> {
         let raw: c_int = getsockopt(self, c::SOL_SOCKET, c::SO_ERROR)?;
         if raw == 0 { Ok(None) } else { Ok(Some(io::Error::from_raw_os_error(raw as i32))) }
     }

     // This is used by sys_common code to abstract over Windows and Unix.
     pub fn as_raw(&self) -> c::SOCKET {
         debug_assert_eq!(size_of::<c::SOCKET>(), size_of::<RawSocket>());
         debug_assert_eq!(align_of::<c::SOCKET>(), align_of::<RawSocket>());
         self.as_inner().as_raw_socket() as c::SOCKET
     }
     pub unsafe fn from_raw(raw: c::SOCKET) -> Self {
         debug_assert_eq!(size_of::<c::SOCKET>(), size_of::<RawSocket>());
         debug_assert_eq!(align_of::<c::SOCKET>(), align_of::<RawSocket>());
         unsafe { Self::from_raw_socket(raw as RawSocket) }
     }
 }

 #[unstable(reason = "not public", issue = "none", feature = "fd_read")]
 impl<'a> Read for &'a Socket {
     fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
         (**self).read(buf)
     }
 }

 impl AsInner<OwnedSocket> for Socket {
     #[inline]
     fn as_inner(&self) -> &OwnedSocket {
         &self.0
     }
 }

 impl FromInner<OwnedSocket> for Socket {
     fn from_inner(sock: OwnedSocket) -> Socket {
         Socket(sock)
     }
 }

 impl IntoInner<OwnedSocket> for Socket {
     fn into_inner(self) -> OwnedSocket {
         self.0
     }
 }

 impl AsSocket for Socket {
     fn as_socket(&self) -> BorrowedSocket<'_> {
         self.0.as_socket()
     }
 }

 impl AsRawSocket for Socket {
     fn as_raw_socket(&self) -> RawSocket {
         self.0.as_raw_socket()
     }
 }

 impl IntoRawSocket for Socket {
     fn into_raw_socket(self) -> RawSocket {
         self.0.into_raw_socket()
     }
 }

 impl FromRawSocket for Socket {
     unsafe fn from_raw_socket(raw_socket: RawSocket) -> Self {
         unsafe { Self(FromRawSocket::from_raw_socket(raw_socket)) }
     }
 }
	#![unstable(issue = "none", feature = "windows_net")]

	use core::ffi::{c_int, c_long, c_ulong, c_ushort};

	use super::{getsockopt, setsockopt, socket_addr_from_c, socket_addr_to_c};
	use crate::io::{self, BorrowedBuf, BorrowedCursor, IoSlice, IoSliceMut, Read};
	use crate::net::{Shutdown, SocketAddr};
	use crate::os::windows::io::{
	AsRawSocket, AsSocket, BorrowedSocket, FromRawSocket, IntoRawSocket, OwnedSocket, RawSocket,
	};
	use crate::sync::atomic::Atomic;
	use crate::sync::atomic::Ordering::{AcqRel, Relaxed};
	use crate::sys::c;
	use crate::sys_common::{AsInner, FromInner, IntoInner};
	use crate::time::Duration;
	use crate::{cmp, mem, ptr, sys};

	#[allow(non_camel_case_types)]
	pub type wrlen_t = i32;

	pub(super) mod netc {
	//! BSD socket compatibility shim
	//!
	//! Some Windows API types are not quite what's expected by our cross-platform
	//! net code. E.g. naming differences or different pointer types.

	use core::ffi::{c_char, c_int, c_uint, c_ulong, c_ushort, c_void};

	use crate::sys::c::{self, ADDRESS_FAMILY, ADDRINFOA, SOCKADDR, SOCKET};
	// re-exports from Windows API bindings.
	pub use crate::sys::c::{
	ADDRESS_FAMILY as sa_family_t, ADDRINFOA as addrinfo, IP_ADD_MEMBERSHIP,
	IP_DROP_MEMBERSHIP, IP_MULTICAST_LOOP, IP_MULTICAST_TTL, IP_TTL, IPPROTO_IP, IPPROTO_IPV6,
	IPV6_ADD_MEMBERSHIP, IPV6_DROP_MEMBERSHIP, IPV6_MULTICAST_LOOP, IPV6_V6ONLY, SO_BROADCAST,
	SO_RCVTIMEO, SO_SNDTIMEO, SOCK_DGRAM, SOCK_STREAM, SOCKADDR as sockaddr,
	SOCKADDR_STORAGE as sockaddr_storage, SOL_SOCKET, bind, connect, freeaddrinfo, getpeername,
	getsockname, getsockopt, listen, setsockopt,
	};

	#[allow(non_camel_case_types)]
	pub type socklen_t = c_int;

	pub const AF_INET: i32 = c::AF_INET as i32;
	pub const AF_INET6: i32 = c::AF_INET6 as i32;

	// The following two structs use a union in the generated bindings but
	// our cross-platform code expects a normal field so it's redefined here.
	// As a consequence, we also need to redefine other structs that use this struct.
	#[repr(C)]
	#[derive(Copy, Clone)]
	pub struct in_addr {
	pub s_addr: u32,
	}

	#[repr(C)]
	#[derive(Copy, Clone)]
	pub struct in6_addr {
	pub s6_addr: [u8; 16],
	}

	#[repr(C)]
	pub struct ip_mreq {
	pub imr_multiaddr: in_addr,
	pub imr_interface: in_addr,
	}

	#[repr(C)]
	pub struct ipv6_mreq {
	pub ipv6mr_multiaddr: in6_addr,
	pub ipv6mr_interface: c_uint,
	}

	#[repr(C)]
	#[derive(Copy, Clone)]
	pub struct sockaddr_in {
	pub sin_family: ADDRESS_FAMILY,
	pub sin_port: c_ushort,
	pub sin_addr: in_addr,
	pub sin_zero: [c_char; 8],
	}

	#[repr(C)]
	#[derive(Copy, Clone)]
	pub struct sockaddr_in6 {
	pub sin6_family: ADDRESS_FAMILY,
	pub sin6_port: c_ushort,
	pub sin6_flowinfo: c_ulong,
	pub sin6_addr: in6_addr,
	pub sin6_scope_id: c_ulong,
	}

	pub unsafe fn send(socket: SOCKET, buf: *const c_void, len: c_int, flags: c_int) -> c_int {
	unsafe { c::send(socket, buf.cast::<u8>(), len, flags) }
	}
	pub unsafe fn sendto(
	socket: SOCKET,
	buf: *const c_void,
	len: c_int,
	flags: c_int,
	addr: *const SOCKADDR,
	addrlen: c_int,
	) -> c_int {
	unsafe { c::sendto(socket, buf.cast::<u8>(), len, flags, addr, addrlen) }
	}
	pub unsafe fn getaddrinfo(
	node: *const c_char,
	service: *const c_char,
	hints: *const ADDRINFOA,
	res: mut mut ADDRINFOA,
	) -> c_int {
	unsafe { c::getaddrinfo(node.cast::<u8>(), service.cast::<u8>(), hints, res) }
	}
	}

	#[expect(missing_debug_implementations)]
	pub struct Socket(OwnedSocket);

	static WSA_INITIALIZED: Atomic<bool> = Atomic::<bool>::new(false);

	/// Checks whether the Windows socket interface has been started already, and
	/// if not, starts it.
	#[inline]
	pub fn init() {
	if !WSA_INITIALIZED.load(Relaxed) {
	wsa_startup();
	}
	}

	#[cold]
	fn wsa_startup() {
	unsafe {
	let mut data: c::WSADATA = mem::zeroed();
	let ret = c::WSAStartup(
	0x202, // version 2.2
	&mut data,
	);
	assert_eq!(ret, 0);
	if WSA_INITIALIZED.swap(true, AcqRel) {
	// If another thread raced with us and called WSAStartup first then call
	// WSACleanup so it's as though WSAStartup was only called once.
	c::WSACleanup();
	}
	}
	}

	pub fn cleanup() {
	// We don't need to call WSACleanup here because exiting the process will cause
	// the OS to clean everything for us, which is faster than doing it manually.
	// See #141799.
	}

	/// Returns the last error from the Windows socket interface.
	fn last_error() -> io::Error {
	io::Error::from_raw_os_error(unsafe { c::WSAGetLastError() })
	}

	#[doc(hidden)]
	pub trait IsMinusOne {
	fn is_minus_one(&self) -> bool;
	}

	macro_rules! impl_is_minus_one {
	($($t:ident)*) => ($(impl IsMinusOne for $t {
	fn is_minus_one(&self) -> bool {
	*self == -1
	}
	})*)
	}

	impl_is_minus_one! { i8 i16 i32 i64 isize }

	/// Checks if the signed integer is the Windows constant `SOCKET_ERROR` (-1)
	/// and if so, returns the last error from the Windows socket interface. This
	/// function must be called before another call to the socket API is made.
	pub fn cvt<T: IsMinusOne>(t: T) -> io::Result<T> {
	if t.is_minus_one() { Err(last_error()) } else { Ok(t) }
	}

	/// A variant of `cvt` for `getaddrinfo` which return 0 for a success.
	pub fn cvt_gai(err: c_int) -> io::Result<()> {
	if err == 0 { Ok(()) } else { Err(last_error()) }
	}

	/// Just to provide the same interface as sys/pal/unix/net.rs
	pub fn cvt_r<T, F>(mut f: F) -> io::Result<T>
	where
	T: IsMinusOne,
	F: FnMut() -> T,
	{
	cvt(f())
	}

	impl Socket {
	pub fn new(addr: &SocketAddr, ty: c_int) -> io::Result<Socket> {
	let family = match *addr {
	SocketAddr::V4(..) => netc::AF_INET,
	SocketAddr::V6(..) => netc::AF_INET6,
	};
	let socket = unsafe {
	c::WSASocketW(
	family,
	ty,
	0,
	ptr::null_mut(),
	0,
	c::WSA_FLAG_OVERLAPPED \| c::WSA_FLAG_NO_HANDLE_INHERIT,
	)
	};

	if socket != c::INVALID_SOCKET {
	unsafe { Ok(Self::from_raw(socket)) }
	} else {
	let error = unsafe { c::WSAGetLastError() };

	if error != c::WSAEPROTOTYPE && error != c::WSAEINVAL {
	return Err(io::Error::from_raw_os_error(error));
	}

	let socket =
	unsafe { c::WSASocketW(family, ty, 0, ptr::null_mut(), 0, c::WSA_FLAG_OVERLAPPED) };

	if socket == c::INVALID_SOCKET {
	return Err(last_error());
	}

	unsafe {
	let socket = Self::from_raw(socket);
	socket.0.set_no_inherit()?;
	Ok(socket)
	}
	}
	}

	pub fn connect(&self, addr: &SocketAddr) -> io::Result<()> {
	let (addr, len) = socket_addr_to_c(addr);
	let result = unsafe { c::connect(self.as_raw(), addr.as_ptr(), len) };
	cvt(result).map(drop)
	}

	pub fn connect_timeout(&self, addr: &SocketAddr, timeout: Duration) -> io::Result<()> {
	self.set_nonblocking(true)?;
	let result = self.connect(addr);
	self.set_nonblocking(false)?;

	match result {
	Err(ref error) if error.kind() == io::ErrorKind::WouldBlock => {
	if timeout.as_secs() == 0 && timeout.subsec_nanos() == 0 {
	return Err(io::Error::ZERO_TIMEOUT);
	}

	let mut timeout = c::TIMEVAL {
	tv_sec: cmp::min(timeout.as_secs(), c_long::MAX as u64) as c_long,
	tv_usec: timeout.subsec_micros() as c_long,
	};

	if timeout.tv_sec == 0 && timeout.tv_usec == 0 {
	timeout.tv_usec = 1;
	}

	let fds = {
	let mut fds = unsafe { mem::zeroed::<c::FD_SET>() };
	fds.fd_count = 1;
	fds.fd_array[0] = self.as_raw();
	fds
	};

	let mut writefds = fds;
	let mut errorfds = fds;

	let count = {
	let result = unsafe {
	c::select(1, ptr::null_mut(), &mut writefds, &mut errorfds, &timeout)
	};
	cvt(result)?
	};

	match count {
	0 => Err(io::const_error!(io::ErrorKind::TimedOut, "connection timed out")),
	_ => {
	if writefds.fd_count != 1 {
	if let Some(e) = self.take_error()? {
	return Err(e);
	}
	}

	Ok(())
	}
	}
	}
	_ => result,
	}
	}

	pub fn accept(&self, storage: mut c::SOCKADDR, len: mut c_int) -> io::Result<Socket> {
	let socket = unsafe { c::accept(self.as_raw(), storage, len) };

	match socket {
	c::INVALID_SOCKET => Err(last_error()),
	_ => unsafe { Ok(Self::from_raw(socket)) },
	}
	}

	pub fn duplicate(&self) -> io::Result<Socket> {
	Ok(Self(self.0.try_clone()?))
	}

	fn recv_with_flags(&self, mut buf: BorrowedCursor<'_>, flags: c_int) -> io::Result<()> {
	// On unix when a socket is shut down all further reads return 0, so we
	// do the same on windows to map a shut down socket to returning EOF.
	let length = cmp::min(buf.capacity(), i32::MAX as usize) as i32;
	let result =
	unsafe { c::recv(self.as_raw(), buf.as_mut().as_mut_ptr() as *mut _, length, flags) };

	match result {
	c::SOCKET_ERROR => {
	let error = unsafe { c::WSAGetLastError() };

	if error == c::WSAESHUTDOWN {
	Ok(())
	} else {
	Err(io::Error::from_raw_os_error(error))
	}
	}
	_ => {
	unsafe { buf.advance_unchecked(result as usize) };
	Ok(())
	}
	}
	}

	pub fn read(&self, buf: &mut [u8]) -> io::Result<usize> {
	let mut buf = BorrowedBuf::from(buf);
	self.recv_with_flags(buf.unfilled(), 0)?;
	Ok(buf.len())
	}

	pub fn read_buf(&self, buf: BorrowedCursor<'_>) -> io::Result<()> {
	self.recv_with_flags(buf, 0)
	}

	pub fn read_vectored(&self, bufs: &mut [IoSliceMut<'_>]) -> io::Result<usize> {
	// On unix when a socket is shut down all further reads return 0, so we
	// do the same on windows to map a shut down socket to returning EOF.
	let length = cmp::min(bufs.len(), u32::MAX as usize) as u32;
	let mut nread = 0;
	let mut flags = 0;
	let result = unsafe {
	c::WSARecv(
	self.as_raw(),
	bufs.as_mut_ptr() as *mut c::WSABUF,
	length,
	&mut nread,
	&mut flags,
	ptr::null_mut(),
	None,
	)
	};

	match result {
	0 => Ok(nread as usize),
	_ => {
	let error = unsafe { c::WSAGetLastError() };

	if error == c::WSAESHUTDOWN {
	Ok(0)
	} else {
	Err(io::Error::from_raw_os_error(error))
	}
	}
	}
	}

	#[inline]
	pub fn is_read_vectored(&self) -> bool {
	true
	}

	pub fn peek(&self, buf: &mut [u8]) -> io::Result<usize> {
	let mut buf = BorrowedBuf::from(buf);
	self.recv_with_flags(buf.unfilled(), c::MSG_PEEK)?;
	Ok(buf.len())
	}

	fn recv_from_with_flags(
	&self,
	buf: &mut [u8],
	flags: c_int,
	) -> io::Result<(usize, SocketAddr)> {
	let mut storage = unsafe { mem::zeroed::<c::SOCKADDR_STORAGE>() };
	let mut addrlen = size_of_val(&storage) as netc::socklen_t;
	let length = cmp::min(buf.len(), <wrlen_t>::MAX as usize) as wrlen_t;

	// On unix when a socket is shut down all further reads return 0, so we
	// do the same on windows to map a shut down socket to returning EOF.
	let result = unsafe {
	c::recvfrom(
	self.as_raw(),
	buf.as_mut_ptr() as *mut _,
	length,
	flags,
	(&raw mut storage) as *mut _,
	&mut addrlen,
	)
	};

	match result {
	c::SOCKET_ERROR => {
	let error = unsafe { c::WSAGetLastError() };

	if error == c::WSAESHUTDOWN {
	Ok((0, unsafe { socket_addr_from_c(&storage, addrlen as usize)? }))
	} else {
	Err(io::Error::from_raw_os_error(error))
	}
	}
	_ => Ok((result as usize, unsafe { socket_addr_from_c(&storage, addrlen as usize)? })),
	}
	}

	pub fn recv_from(&self, buf: &mut [u8]) -> io::Result<(usize, SocketAddr)> {
	self.recv_from_with_flags(buf, 0)
	}

	pub fn peek_from(&self, buf: &mut [u8]) -> io::Result<(usize, SocketAddr)> {
	self.recv_from_with_flags(buf, c::MSG_PEEK)
	}

	pub fn write_vectored(&self, bufs: &[IoSlice<'_>]) -> io::Result<usize> {
	let length = cmp::min(bufs.len(), u32::MAX as usize) as u32;
	let mut nwritten = 0;
	let result = unsafe {
	c::WSASend(
	self.as_raw(),
	bufs.as_ptr() as const c::WSABUF as mut _,
	length,
	&mut nwritten,
	0,
	ptr::null_mut(),
	None,
	)
	};
	cvt(result).map(\|_\| nwritten as usize)
	}

	#[inline]
	pub fn is_write_vectored(&self) -> bool {
	true
	}

	pub fn set_timeout(&self, dur: Option<Duration>, kind: c_int) -> io::Result<()> {
	let timeout = match dur {
	Some(dur) => {
	let timeout = sys::dur2timeout(dur);
	if timeout == 0 {
	return Err(io::Error::ZERO_TIMEOUT);
	}
	timeout
	}
	None => 0,
	};
	setsockopt(self, c::SOL_SOCKET, kind, timeout)
	}

	pub fn timeout(&self, kind: c_int) -> io::Result<Option<Duration>> {
	let raw: u32 = getsockopt(self, c::SOL_SOCKET, kind)?;
	if raw == 0 {
	Ok(None)
	} else {
	let secs = raw / 1000;
	let nsec = (raw % 1000) * 1000000;
	Ok(Some(Duration::new(secs as u64, nsec as u32)))
	}
	}

	pub fn shutdown(&self, how: Shutdown) -> io::Result<()> {
	let how = match how {
	Shutdown::Write => c::SD_SEND,
	Shutdown::Read => c::SD_RECEIVE,
	Shutdown::Both => c::SD_BOTH,
	};
	let result = unsafe { c::shutdown(self.as_raw(), how) };
	cvt(result).map(drop)
	}

	pub fn set_nonblocking(&self, nonblocking: bool) -> io::Result<()> {
	let mut nonblocking = nonblocking as c_ulong;
	let result =
	unsafe { c::ioctlsocket(self.as_raw(), c::FIONBIO as c_int, &mut nonblocking) };
	cvt(result).map(drop)
	}

	pub fn set_linger(&self, linger: Option<Duration>) -> io::Result<()> {
	let linger = c::LINGER {
	l_onoff: linger.is_some() as c_ushort,
	l_linger: linger.unwrap_or_default().as_secs() as c_ushort,
	};

	setsockopt(self, c::SOL_SOCKET, c::SO_LINGER, linger)
	}

	pub fn linger(&self) -> io::Result<Option<Duration>> {
	let val: c::LINGER = getsockopt(self, c::SOL_SOCKET, c::SO_LINGER)?;

	Ok((val.l_onoff != 0).then(\|\| Duration::from_secs(val.l_linger as u64)))
	}

	pub fn set_nodelay(&self, nodelay: bool) -> io::Result<()> {
	setsockopt(self, c::IPPROTO_TCP, c::TCP_NODELAY, nodelay as c::BOOL)
	}

	pub fn nodelay(&self) -> io::Result<bool> {
	let raw: c::BOOL = getsockopt(self, c::IPPROTO_TCP, c::TCP_NODELAY)?;
	Ok(raw != 0)
	}

	pub fn take_error(&self) -> io::Result<Option<io::Error>> {
	let raw: c_int = getsockopt(self, c::SOL_SOCKET, c::SO_ERROR)?;
	if raw == 0 { Ok(None) } else { Ok(Some(io::Error::from_raw_os_error(raw as i32))) }
	}

	// This is used by sys_common code to abstract over Windows and Unix.
	pub fn as_raw(&self) -> c::SOCKET {
	debug_assert_eq!(size_of::<c::SOCKET>(), size_of::<RawSocket>());
	debug_assert_eq!(align_of::<c::SOCKET>(), align_of::<RawSocket>());
	self.as_inner().as_raw_socket() as c::SOCKET
	}
	pub unsafe fn from_raw(raw: c::SOCKET) -> Self {
	debug_assert_eq!(size_of::<c::SOCKET>(), size_of::<RawSocket>());
	debug_assert_eq!(align_of::<c::SOCKET>(), align_of::<RawSocket>());
	unsafe { Self::from_raw_socket(raw as RawSocket) }
	}
	}

	#[unstable(reason = "not public", issue = "none", feature = "fd_read")]
	impl<'a> Read for &'a Socket {
	fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
	(**self).read(buf)
	}
	}

	impl AsInner<OwnedSocket> for Socket {
	#[inline]
	fn as_inner(&self) -> &OwnedSocket {
	&self.0
	}
	}

	impl FromInner<OwnedSocket> for Socket {
	fn from_inner(sock: OwnedSocket) -> Socket {
	Socket(sock)
	}
	}

	impl IntoInner<OwnedSocket> for Socket {
	fn into_inner(self) -> OwnedSocket {
	self.0
	}
	}

	impl AsSocket for Socket {
	fn as_socket(&self) -> BorrowedSocket<'_> {
	self.0.as_socket()
	}
	}

	impl AsRawSocket for Socket {
	fn as_raw_socket(&self) -> RawSocket {
	self.0.as_raw_socket()
	}
	}

	impl IntoRawSocket for Socket {
	fn into_raw_socket(self) -> RawSocket {
	self.0.into_raw_socket()
	}
	}

	impl FromRawSocket for Socket {
	unsafe fn from_raw_socket(raw_socket: RawSocket) -> Self {
	unsafe { Self(FromRawSocket::from_raw_socket(raw_socket)) }
	}
	}