Fix OSError.winerror and errno/winerror converions

Cargo.lock

@@ -2063,6 +2063,7 @@ dependencies = [
  "siphasher",
  "volatile",
  "widestring",
+ "windows-sys 0.52.0",
 ]
 
 [[package]]

Cargo.toml

@@ -81,6 +81,7 @@ thiserror = "1.0"
 thread_local = "1.1.4"
 unicode_names2 = "1.1.0"
 widestring = "1.1.0"
+windows-sys = "0.52.0"
 
 [features]
 default = ["threading", "stdlib", "zlib", "importlib"]

Lib/test/test_tempfile.py

@@ -1418,7 +1418,6 @@ class TestTemporaryDirectory(BaseTestCase):
             with open(os.path.join(path, "test%d.txt" % i), "wb") as f:
                 f.write(b"Hello world!")
 
-    @unittest.expectedFailureIfWindows("TODO: RUSTPYTHON")
     def test_mkdtemp_failure(self):
         # Check no additional exception if mkdtemp fails
         # Previously would raise AttributeError instead

common/Cargo.toml

@@ -35,3 +35,7 @@ volatile = "0.3"
 
 [target.'cfg(windows)'.dependencies]
 widestring = { workspace = true }
+windows-sys = { workspace = true, features = [
+    "Win32_Foundation",
+    "Win32_Networking_WinSock",
+] }

common/src/crt_fd.rs

@@ -23,7 +23,7 @@ pub type Offset = libc::c_longlong;
 #[inline]
 fn cvt<T, I: num_traits::PrimInt>(ret: I, f: impl FnOnce(I) -> T) -> io::Result<T> {
     if ret < I::zero() {
-        Err(crate::os::errno())
+        Err(crate::os::last_os_error())
     } else {
         Ok(f(ret))
     }
@@ -86,7 +86,7 @@ impl Fd {
     }
 }
 
-impl io::Write for &Fd {
+impl io::Write for Fd {
     fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
         let count = cmp::min(buf.len(), MAX_RW);
         cvt(
@@ -101,19 +101,7 @@ impl io::Write for &Fd {
     }
 }
 
-impl io::Write for Fd {
-    #[inline]
-    fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
-        (&*self).write(buf)
-    }
-
-    #[inline]
-    fn flush(&mut self) -> io::Result<()> {
-        (&*self).flush()
-    }
-}
-
-impl io::Read for &Fd {
+impl io::Read for Fd {
     fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
         let count = cmp::min(buf.len(), MAX_RW);
         cvt(
@@ -122,10 +110,3 @@ impl io::Read for &Fd {
         )
     }
 }
-
-impl io::Read for Fd {
-    #[inline]
-    fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
-        (&*self).read(buf)
-    }
-}

common/src/os.rs

@@ -2,26 +2,64 @@
 
 use std::{io, str::Utf8Error};
 
+pub trait ErrorExt {
+    fn posix_errno(&self) -> i32;
+}
+
+impl ErrorExt for io::Error {
+    #[cfg(not(windows))]
+    fn posix_errno(&self) -> i32 {
+        self.raw_os_error().unwrap_or(0)
+    }
+    #[cfg(windows)]
+    fn posix_errno(&self) -> i32 {
+        let winerror = self.raw_os_error().unwrap_or(0);
+        winerror_to_errno(winerror)
+    }
+}
+
 #[cfg(windows)]
-pub fn errno() -> io::Error {
+pub fn last_os_error() -> io::Error {
     let err = io::Error::last_os_error();
     // FIXME: probably not ideal, we need a bigger dichotomy between GetLastError and errno
     if err.raw_os_error() == Some(0) {
         extern "C" {
             fn _get_errno(pValue: *mut i32) -> i32;
         }
-        let mut e = 0;
-        unsafe { suppress_iph!(_get_errno(&mut e)) };
-        io::Error::from_raw_os_error(e)
+        let mut errno = 0;
+        unsafe { suppress_iph!(_get_errno(&mut errno)) };
+        let errno = errno_to_winerror(errno);
+        io::Error::from_raw_os_error(errno)
     } else {
         err
     }
 }
+
 #[cfg(not(windows))]
-pub fn errno() -> io::Error {
+pub fn last_os_error() -> io::Error {
     io::Error::last_os_error()
 }
 
+#[cfg(windows)]
+pub fn last_posix_errno() -> i32 {
+    let err = io::Error::last_os_error();
+    if err.raw_os_error() == Some(0) {
+        extern "C" {
+            fn _get_errno(pValue: *mut i32) -> i32;
+        }
+        let mut errno = 0;
+        unsafe { suppress_iph!(_get_errno(&mut errno)) };
+        errno
+    } else {
+        err.posix_errno()
+    }
+}
+
+#[cfg(not(windows))]
+pub fn last_posix_errno() -> i32 {
+    last_os_error().posix_errno()
+}
+
 #[cfg(unix)]
 pub fn bytes_as_osstr(b: &[u8]) -> Result<&std::ffi::OsStr, Utf8Error> {
     use std::os::unix::ffi::OsStrExt;
@@ -37,3 +75,133 @@ pub fn bytes_as_osstr(b: &[u8]) -> Result<&std::ffi::OsStr, Utf8Error> {
 pub use std::os::unix::ffi;
 #[cfg(target_os = "wasi")]
 pub use std::os::wasi::ffi;
+
+#[cfg(windows)]
+pub fn errno_to_winerror(errno: i32) -> i32 {
+    use libc::*;
+    use windows_sys::Win32::Foundation::*;
+    let winerror = match errno {
+        ENOENT => ERROR_FILE_NOT_FOUND,
+        E2BIG => ERROR_BAD_ENVIRONMENT,
+        ENOEXEC => ERROR_BAD_FORMAT,
+        EBADF => ERROR_INVALID_HANDLE,
+        ECHILD => ERROR_WAIT_NO_CHILDREN,
+        EAGAIN => ERROR_NO_PROC_SLOTS,
+        ENOMEM => ERROR_NOT_ENOUGH_MEMORY,
+        EACCES => ERROR_ACCESS_DENIED,
+        EEXIST => ERROR_FILE_EXISTS,
+        EXDEV => ERROR_NOT_SAME_DEVICE,
+        ENOTDIR => ERROR_DIRECTORY,
+        EMFILE => ERROR_TOO_MANY_OPEN_FILES,
+        ENOSPC => ERROR_DISK_FULL,
+        EPIPE => ERROR_BROKEN_PIPE,
+        ENOTEMPTY => ERROR_DIR_NOT_EMPTY,
+        EILSEQ => ERROR_NO_UNICODE_TRANSLATION,
+        EINVAL => ERROR_INVALID_FUNCTION,
+        _ => ERROR_INVALID_FUNCTION,
+    };
+    winerror as _
+}
+
+// winerror: https://learn.microsoft.com/windows/win32/debug/system-error-codes--0-499-
+// errno: https://learn.microsoft.com/cpp/c-runtime-library/errno-constants?view=msvc-170
+#[cfg(windows)]
+pub fn winerror_to_errno(winerror: i32) -> i32 {
+    use libc::*;
+    use windows_sys::Win32::{
+        Foundation::*,
+        Networking::WinSock::{WSAEACCES, WSAEBADF, WSAEFAULT, WSAEINTR, WSAEINVAL, WSAEMFILE},
+    };
+    // Unwrap FACILITY_WIN32 HRESULT errors.
+    // if ((winerror & 0xFFFF0000) == 0x80070000) {
+    //     winerror &= 0x0000FFFF;
+    // }
+
+    // Winsock error codes (10000-11999) are errno values.
+    if (10000..12000).contains(&winerror) {
+        match winerror {
+            WSAEINTR | WSAEBADF | WSAEACCES | WSAEFAULT | WSAEINVAL | WSAEMFILE => {
+                // Winsock definitions of errno values. See WinSock2.h
+                return winerror - 10000;
+            }
+            _ => return winerror as _,
+        }
+    }
+
+    #[allow(non_upper_case_globals)]
+    match winerror as u32 {
+        ERROR_FILE_NOT_FOUND
+        | ERROR_PATH_NOT_FOUND
+        | ERROR_INVALID_DRIVE
+        | ERROR_NO_MORE_FILES
+        | ERROR_BAD_NETPATH
+        | ERROR_BAD_NET_NAME
+        | ERROR_BAD_PATHNAME
+        | ERROR_FILENAME_EXCED_RANGE => ENOENT,
+        ERROR_BAD_ENVIRONMENT => E2BIG,
+        ERROR_BAD_FORMAT
+        | ERROR_INVALID_STARTING_CODESEG
+        | ERROR_INVALID_STACKSEG
+        | ERROR_INVALID_MODULETYPE
+        | ERROR_INVALID_EXE_SIGNATURE
+        | ERROR_EXE_MARKED_INVALID
+        | ERROR_BAD_EXE_FORMAT
+        | ERROR_ITERATED_DATA_EXCEEDS_64k
+        | ERROR_INVALID_MINALLOCSIZE
+        | ERROR_DYNLINK_FROM_INVALID_RING
+        | ERROR_IOPL_NOT_ENABLED
+        | ERROR_INVALID_SEGDPL
+        | ERROR_AUTODATASEG_EXCEEDS_64k
+        | ERROR_RING2SEG_MUST_BE_MOVABLE
+        | ERROR_RELOC_CHAIN_XEEDS_SEGLIM
+        | ERROR_INFLOOP_IN_RELOC_CHAIN => ENOEXEC,
+        ERROR_INVALID_HANDLE | ERROR_INVALID_TARGET_HANDLE | ERROR_DIRECT_ACCESS_HANDLE => EBADF,
+        ERROR_WAIT_NO_CHILDREN | ERROR_CHILD_NOT_COMPLETE => ECHILD,
+        ERROR_NO_PROC_SLOTS | ERROR_MAX_THRDS_REACHED | ERROR_NESTING_NOT_ALLOWED => EAGAIN,
+        ERROR_ARENA_TRASHED
+        | ERROR_NOT_ENOUGH_MEMORY
+        | ERROR_INVALID_BLOCK
+        | ERROR_NOT_ENOUGH_QUOTA => ENOMEM,
+        ERROR_ACCESS_DENIED
+        | ERROR_CURRENT_DIRECTORY
+        | ERROR_WRITE_PROTECT
+        | ERROR_BAD_UNIT
+        | ERROR_NOT_READY
+        | ERROR_BAD_COMMAND
+        | ERROR_CRC
+        | ERROR_BAD_LENGTH
+        | ERROR_SEEK
+        | ERROR_NOT_DOS_DISK
+        | ERROR_SECTOR_NOT_FOUND
+        | ERROR_OUT_OF_PAPER
+        | ERROR_WRITE_FAULT
+        | ERROR_READ_FAULT
+        | ERROR_GEN_FAILURE
+        | ERROR_SHARING_VIOLATION
+        | ERROR_LOCK_VIOLATION
+        | ERROR_WRONG_DISK
+        | ERROR_SHARING_BUFFER_EXCEEDED
+        | ERROR_NETWORK_ACCESS_DENIED
+        | ERROR_CANNOT_MAKE
+        | ERROR_FAIL_I24
+        | ERROR_DRIVE_LOCKED
+        | ERROR_SEEK_ON_DEVICE
+        | ERROR_NOT_LOCKED
+        | ERROR_LOCK_FAILED
+        | 35 => EACCES,
+        ERROR_FILE_EXISTS | ERROR_ALREADY_EXISTS => EEXIST,
+        ERROR_NOT_SAME_DEVICE => EXDEV,
+        ERROR_DIRECTORY => ENOTDIR,
+        ERROR_TOO_MANY_OPEN_FILES => EMFILE,
+        ERROR_DISK_FULL => ENOSPC,
+        ERROR_BROKEN_PIPE | ERROR_NO_DATA => EPIPE,
+        ERROR_DIR_NOT_EMPTY => ENOTEMPTY,
+        ERROR_NO_UNICODE_TRANSLATION => EILSEQ,
+        ERROR_INVALID_FUNCTION
+        | ERROR_INVALID_ACCESS
+        | ERROR_INVALID_DATA
+        | ERROR_INVALID_PARAMETER
+        | ERROR_NEGATIVE_SEEK => EINVAL,
+        _ => EINVAL,
+    }
+}

stdlib/Cargo.toml

@@ -117,7 +117,7 @@ features = [
 ]
 
 [target.'cfg(windows)'.dependencies.windows-sys]
-version = "0.52.0"
+workspace = true
 features = [
   "Win32_Networking_WinSock",
   "Win32_NetworkManagement_IpHelper",

stdlib/src/socket.rs

@@ -13,6 +13,7 @@ mod _socket {
     use crate::common::lock::{PyMappedRwLockReadGuard, PyRwLock, PyRwLockReadGuard};
     use crate::vm::{
         builtins::{PyBaseExceptionRef, PyListRef, PyStrRef, PyTupleRef, PyTypeRef},
+        common::os::ErrorExt,
         convert::{IntoPyException, ToPyObject, TryFromBorrowedObject, TryFromObject},
         function::{ArgBytesLike, ArgMemoryBuffer, Either, FsPath, OptionalArg, OptionalOption},
         types::{DefaultConstructor, Initializer, Representable},
@@ -1018,7 +1019,7 @@ mod _socket {
                     let sock = self.sock()?;
                     let err = sock.take_error()?;
                     match err {
-                        Some(e) if e.raw_os_error() == Some(libc::EISCONN) => Ok(()),
+                        Some(e) if e.posix_errno() == libc::EISCONN => Ok(()),
                         Some(e) => Err(e),
                         // TODO: is this accurate?
                         None => Ok(()),
@@ -1408,7 +1409,7 @@ mod _socket {
                     )
                 };
                 if ret < 0 {
-                    return Err(crate::common::os::errno().into());
+                    return Err(crate::common::os::last_os_error().into());
                 }
                 Ok(vm.ctx.new_int(flag).into())
             } else {
@@ -1429,7 +1430,7 @@ mod _socket {
                     )
                 };
                 if ret < 0 {
-                    return Err(crate::common::os::errno().into());
+                    return Err(crate::common::os::last_os_error().into());
                 }
                 buf.truncate(buflen as usize);
                 Ok(vm.ctx.new_bytes(buf).into())
@@ -1470,7 +1471,7 @@ mod _socket {
                 }
             };
             if ret < 0 {
-                Err(crate::common::os::errno().into())
+                Err(crate::common::os::last_os_error().into())
             } else {
                 Ok(())
             }
@@ -1694,10 +1695,7 @@ mod _socket {
         fn errno(self) -> PyResult<i32> {
             match self {
                 Self::Timeout => Ok(errcode!(EWOULDBLOCK)),
-                Self::Io(err) => {
-                    // TODO: just unwrap()?
-                    Ok(err.raw_os_error().unwrap_or(1))
-                }
+                Self::Io(err) => Ok(err.posix_errno()),
                 Self::Py(exc) => Err(exc),
             }
         }
@@ -2354,7 +2352,7 @@ mod _socket {
         use windows_sys::Win32::Networking::WinSock::closesocket as close;
         let ret = unsafe { close(x as _) };
         if ret < 0 {
-            let err = crate::common::os::errno();
+            let err = crate::common::os::last_os_error();
             if err.raw_os_error() != Some(errcode!(ECONNRESET)) {
                 return Err(err);
             }

stdlib/src/ssl.rs

@@ -680,7 +680,7 @@ mod _ssl {
                     )
                 };
                 if ret != 1 {
-                    let errno = std::io::Error::last_os_error().raw_os_error().unwrap();
+                    let errno = crate::common::os::last_posix_errno();
                     let err = if errno != 0 {
                         crate::vm::stdlib::os::errno_err(vm)
                     } else {

stdlib/src/termios.rs

@@ -4,6 +4,7 @@ pub(crate) use self::termios::make_module;
 mod termios {
     use crate::vm::{
         builtins::{PyBaseExceptionRef, PyBytes, PyInt, PyListRef, PyTypeRef},
+        common::os::ErrorExt,
         convert::ToPyObject,
         PyObjectRef, PyResult, TryFromObject, VirtualMachine,
     };
@@ -259,7 +260,7 @@ mod termios {
         vm.new_exception(
             error_type(vm),
             vec![
-                err.raw_os_error().to_pyobject(vm),
+                err.posix_errno().to_pyobject(vm),
                 vm.ctx.new_str(err.to_string()).into(),
             ],
         )

vm/Cargo.toml

@@ -119,7 +119,7 @@ features = [
 ]
 
 [target.'cfg(windows)'.dependencies.windows-sys]
-version = "0.52.0"
+workspace = true
 features = [
   "Win32_Foundation",
   "Win32_Networking_WinSock",

vm/src/exceptions.rs

@@ -800,10 +800,8 @@ impl ExceptionZoo {
             // second exception filename
             "filename2" => ctx.none(),
         });
-        // TODO: this isn't really accurate
         #[cfg(windows)]
-        excs.os_error
-            .set_str_attr("winerror", errno_getter.clone(), ctx);
+        excs.os_error.set_str_attr("winerror", ctx.none(), ctx);
 
         extend_exception!(PyBlockingIOError, ctx, excs.blocking_io_error);
         extend_exception!(PyChildProcessError, ctx, excs.child_process_error);
@@ -1013,14 +1011,9 @@ impl<C> ToPyException for widestring::error::ContainsNul<C> {
 }
 
 #[cfg(any(unix, windows, target_os = "wasi"))]
-pub(crate) fn raw_os_error_to_exc_type(
-    errno: i32,
-    vm: &VirtualMachine,
-) -> Option<&'static Py<PyType>> {
+pub(crate) fn errno_to_exc_type(errno: i32, vm: &VirtualMachine) -> Option<&'static Py<PyType>> {
     use crate::stdlib::errno::errors;
     let excs = &vm.ctx.exceptions;
-    #[cfg(windows)]
-    let errno = win_error_to_errno(errno as u32);
     match errno {
         errors::EWOULDBLOCK => Some(excs.blocking_io_error),
         errors::EALREADY => Some(excs.blocking_io_error),
@@ -1045,111 +1038,8 @@ pub(crate) fn raw_os_error_to_exc_type(
     }
 }
 
-#[cfg(windows)]
-pub(crate) fn win_error_to_errno(winerror: u32) -> i32 {
-    use crate::stdlib::errno::errors;
-    use windows_sys::Win32::Foundation::*;
-    // Unwrap FACILITY_WIN32 HRESULT errors.
-    // if ((winerror & 0xFFFF0000) == 0x80070000) {
-    //     winerror &= 0x0000FFFF;
-    // }
-
-    // Winsock error codes (10000-11999) are errno values.
-    // if winerror >= 10000 && winerror < 12000 {
-    //     match winerror {
-    //         WSAEINTR | WSAEBADF | WSAEACCES | WSAEFAULT | WSAEINVAL | WSAEMFILE => {
-    //             // Winsock definitions of errno values. See WinSock2.h
-    //             return winerror - 10000;
-    //         },
-    //         _ => return winerror,
-    //     }
-    // }
-
-    #[allow(non_upper_case_globals)]
-    match winerror {
-        ERROR_FILE_NOT_FOUND
-        | ERROR_PATH_NOT_FOUND
-        | ERROR_INVALID_DRIVE
-        | ERROR_NO_MORE_FILES
-        | ERROR_BAD_NETPATH
-        | ERROR_BAD_NET_NAME
-        | ERROR_BAD_PATHNAME
-        | ERROR_FILENAME_EXCED_RANGE => errors::ENOENT,
-        ERROR_BAD_ENVIRONMENT => errors::E2BIG,
-        ERROR_BAD_FORMAT
-        | ERROR_INVALID_STARTING_CODESEG
-        | ERROR_INVALID_STACKSEG
-        | ERROR_INVALID_MODULETYPE
-        | ERROR_INVALID_EXE_SIGNATURE
-        | ERROR_EXE_MARKED_INVALID
-        | ERROR_BAD_EXE_FORMAT
-        | ERROR_ITERATED_DATA_EXCEEDS_64k
-        | ERROR_INVALID_MINALLOCSIZE
-        | ERROR_DYNLINK_FROM_INVALID_RING
-        | ERROR_IOPL_NOT_ENABLED
-        | ERROR_INVALID_SEGDPL
-        | ERROR_AUTODATASEG_EXCEEDS_64k
-        | ERROR_RING2SEG_MUST_BE_MOVABLE
-        | ERROR_RELOC_CHAIN_XEEDS_SEGLIM
-        | ERROR_INFLOOP_IN_RELOC_CHAIN => errors::ENOEXEC,
-        ERROR_INVALID_HANDLE | ERROR_INVALID_TARGET_HANDLE | ERROR_DIRECT_ACCESS_HANDLE => {
-            errors::EBADF
-        }
-        ERROR_WAIT_NO_CHILDREN | ERROR_CHILD_NOT_COMPLETE => errors::ECHILD,
-        ERROR_NO_PROC_SLOTS | ERROR_MAX_THRDS_REACHED | ERROR_NESTING_NOT_ALLOWED => errors::EAGAIN,
-        ERROR_ARENA_TRASHED
-        | ERROR_NOT_ENOUGH_MEMORY
-        | ERROR_INVALID_BLOCK
-        | ERROR_NOT_ENOUGH_QUOTA => errors::ENOMEM,
-        ERROR_ACCESS_DENIED
-        | ERROR_CURRENT_DIRECTORY
-        | ERROR_WRITE_PROTECT
-        | ERROR_BAD_UNIT
-        | ERROR_NOT_READY
-        | ERROR_BAD_COMMAND
-        | ERROR_CRC
-        | ERROR_BAD_LENGTH
-        | ERROR_SEEK
-        | ERROR_NOT_DOS_DISK
-        | ERROR_SECTOR_NOT_FOUND
-        | ERROR_OUT_OF_PAPER
-        | ERROR_WRITE_FAULT
-        | ERROR_READ_FAULT
-        | ERROR_GEN_FAILURE
-        | ERROR_SHARING_VIOLATION
-        | ERROR_LOCK_VIOLATION
-        | ERROR_WRONG_DISK
-        | ERROR_SHARING_BUFFER_EXCEEDED
-        | ERROR_NETWORK_ACCESS_DENIED
-        | ERROR_CANNOT_MAKE
-        | ERROR_FAIL_I24
-        | ERROR_DRIVE_LOCKED
-        | ERROR_SEEK_ON_DEVICE
-        | ERROR_NOT_LOCKED
-        | ERROR_LOCK_FAILED
-        | 35 => errors::EACCES,
-        ERROR_FILE_EXISTS | ERROR_ALREADY_EXISTS => errors::EEXIST,
-        ERROR_NOT_SAME_DEVICE => errors::EXDEV,
-        ERROR_DIRECTORY => errors::ENOTDIR,
-        ERROR_TOO_MANY_OPEN_FILES => errors::EMFILE,
-        ERROR_DISK_FULL => errors::ENOSPC,
-        ERROR_BROKEN_PIPE | ERROR_NO_DATA => errors::EPIPE,
-        ERROR_DIR_NOT_EMPTY => errors::ENOTEMPTY,
-        ERROR_NO_UNICODE_TRANSLATION => errors::EILSEQ,
-        ERROR_INVALID_FUNCTION
-        | ERROR_INVALID_ACCESS
-        | ERROR_INVALID_DATA
-        | ERROR_INVALID_PARAMETER
-        | ERROR_NEGATIVE_SEEK => errors::EINVAL,
-        _ => errors::EINVAL,
-    }
-}
-
 #[cfg(all(target_arch = "wasm32", not(target_os = "wasi")))]
-pub(crate) fn raw_os_error_to_exc_type(
-    _errno: i32,
-    _vm: &VirtualMachine,
-) -> Option<&'static Py<PyType>> {
+pub(crate) fn errno_to_exc_type(_errno: i32, _vm: &VirtualMachine) -> Option<&'static Py<PyType>> {
     None
 }
 
@@ -1359,7 +1249,7 @@ pub(super) mod types {
                 errno
                     .payload_if_subclass::<PyInt>(vm)
                     .and_then(|errno| errno.try_to_primitive::<i32>(vm).ok())
-                    .and_then(|errno| super::raw_os_error_to_exc_type(errno, vm))
+                    .and_then(|errno| super::errno_to_exc_type(errno, vm))
                     .and_then(|typ| vm.invoke_exception(typ.to_owned(), args.to_vec()).ok())
             } else {
                 None
@@ -1392,8 +1282,12 @@ pub(super) mod types {
             let mut new_args = args;
             if (3..=5).contains(&len) {
                 zelf.set_attr("filename", new_args.args[2].clone(), vm)?;
-                if len == 5 {
-                    zelf.set_attr("filename2", new_args.args[4].clone(), vm)?;
+                #[cfg(windows)]
+                if let Some(winerror) = new_args.args.get(3) {
+                    zelf.set_attr("winerror", winerror.clone(), vm)?;
+                }
+                if let Some(filename2) = new_args.args.get(4) {
+                    zelf.set_attr("filename2", filename2.clone(), vm)?;
                 }
 
                 new_args.args.truncate(2);

vm/src/stdlib/io.rs

@@ -10,9 +10,9 @@ cfg_if::cfg_if! {
 }
 
 use crate::{
-    builtins::PyBaseExceptionRef,
-    builtins::PyModule,
-    convert::{IntoPyException, ToPyException, ToPyObject},
+    builtins::{PyBaseExceptionRef, PyModule},
+    common::os::ErrorExt,
+    convert::{IntoPyException, ToPyException},
     PyObjectRef, PyRef, PyResult, TryFromObject, VirtualMachine,
 };
 pub use _io::io_open as open;
@@ -28,14 +28,32 @@ impl ToPyException for std::io::Error {
             ErrorKind::PermissionDenied => excs.permission_error,
             ErrorKind::AlreadyExists => excs.file_exists_error,
             ErrorKind::WouldBlock => excs.blocking_io_error,
-            _ => self
-                .raw_os_error()
-                .and_then(|errno| crate::exceptions::raw_os_error_to_exc_type(errno, vm))
+            _ => crate::exceptions::errno_to_exc_type(self.posix_errno(), vm)
                 .unwrap_or(excs.os_error),
         };
-        let errno = self.raw_os_error().to_pyobject(vm);
+
+        let errno = self.raw_os_error().unwrap_or(0);
+        let errno_obj = vm.new_pyobj(errno);
+        #[cfg(windows)]
+        let (winerror_obj, errno_obj) = {
+            let winerror = errno;
+            let winerror_obj = errno_obj.clone();
+            let errno = crate::common::os::winerror_to_errno(winerror);
+            (winerror_obj, vm.new_pyobj(errno))
+        };
+
         let msg = vm.ctx.new_str(self.to_string()).into();
-        vm.new_exception(exc_type.to_owned(), vec![errno, msg])
+        #[allow(clippy::let_and_return)]
+        let exc = vm.new_exception(exc_type.to_owned(), vec![errno_obj, msg]);
+        #[cfg(windows)]
+        {
+            // FIXME: manual setup winerror due to lack of OSError.__init__ support
+            use crate::object::AsObject;
+            exc.as_object()
+                .set_attr("winerror", vm.new_pyobj(winerror_obj), vm)
+                .unwrap();
+        }
+        exc
     }
 }
 

vm/src/stdlib/nt.rs

@@ -14,7 +14,7 @@ pub(crate) mod module {
     use crate::builtins::PyListRef;
     use crate::{
         builtins::{PyDictRef, PyStrRef, PyTupleRef},
-        common::{crt_fd::Fd, os::errno, suppress_iph},
+        common::{crt_fd::Fd, os::last_os_error, suppress_iph},
         convert::ToPyException,
         function::Either,
         function::OptionalArg,
@@ -385,7 +385,7 @@ pub(crate) mod module {
             Foundation::SetHandleInformation(handle as _, Foundation::HANDLE_FLAG_INHERIT, flags)
         };
         if res == 0 {
-            Err(errno())
+            Err(last_os_error())
         } else {
             Ok(())
         }

vm/src/stdlib/os.rs

@@ -1,7 +1,7 @@
 use crate::{
     builtins::{PyBaseExceptionRef, PyModule, PySet},
     common::crt_fd::Fd,
-    convert::IntoPyException,
+    convert::{IntoPyException, ToPyException},
     function::{ArgumentError, FromArgs, FsPath, FuncArgs},
     AsObject, Py, PyObjectRef, PyPayload, PyResult, TryFromObject, VirtualMachine,
 };
@@ -205,7 +205,7 @@ impl IntoPyException for IOErrorBuilder {
 /// Convert the error stored in the `errno` variable into an Exception
 #[inline]
 pub fn errno_err(vm: &VirtualMachine) -> PyBaseExceptionRef {
-    crate::common::os::errno().into_pyexception(vm)
+    crate::common::os::last_os_error().to_pyexception(vm)
 }
 
 #[allow(dead_code)]