RustPython
diff --git a/‎crates/host_env/src/ctypes.rs‎
Lines changed: 11 additions & 7 deletions b/‎crates/host_env/src/ctypes.rs‎
Lines changed: 11 additions & 7 deletions
diff --git a/‎crates/host_env/src/fileutils.rs‎
Lines changed: 11 additions & 18 deletions b/‎crates/host_env/src/fileutils.rs‎
Lines changed: 11 additions & 18 deletions
@@ -33,8 +33,7 @@ use libloading::Library;
 use libloading::os::unix::Library as UnixLibrary;
 #[cfg(any(unix, windows))]
 use parking_lot::{Mutex, RwLock};
-use rustpython_wtf8::Wtf8;
-use rustpython_wtf8::Wtf8Buf;
+use rustpython_wtf8::{Wtf8, Wtf8Buf};
 #[cfg(any(unix, windows))]
 use std::{collections::HashMap, ffi::OsStr, sync::OnceLock};
 use widestring::WideCStr;
@@ -503,7 +502,7 @@ pub fn encode_wtf8_to_wchar_padded(s: &Wtf8, size: usize) -> Vec<u8> {
     wchar_bytes
 }
 
-pub fn wchar_null_terminated_bytes(s: &Wtf8) -> Vec<u8> {
+pub fn clone_wchar_null_terminated(s: &Wtf8) -> Vec<u8> {
     if size_of::<WChar>() == 2 {
         // We can't cast u32 to WChar because it would truncate the value on platforms where WChar
         // is two bytes. Wtf8::encode_wide does all of the hard work for us, so all we have to do
@@ -1091,10 +1090,15 @@ pub fn utf16z_bytes(s: &Wtf8) -> Vec<u8> {
         .collect()
 }
 
-pub fn null_terminated_bytes(bytes: &[u8]) -> Vec<u8> {
-    let mut buffer = bytes.to_vec();
-    buffer.push(0);
-    buffer
+/// Return a NUL terminated copy of `bytes`.
+///
+/// The input may contain interior NULs.
+pub fn clone_as_null_terminated(bytes: &[u8]) -> Vec<u8> {
+    if bytes.last() == Some(&0) {
+        bytes.to_vec()
+    } else {
+        bytes.iter().copied().chain(Some(0)).collect()
+    }
 }
 
 pub fn decode_type_code(type_code: &str, bytes: &[u8]) -> DecodedValue {
 
@@ -17,10 +17,10 @@ pub fn fstat(fd: crate::crt_fd::Borrowed<'_>) -> std::io::Result<StatStruct> {
 #[cfg(windows)]
 pub mod windows {
     use crate::crt_fd;
-    use crate::windows::ToWideString;
     use libc::{S_IFCHR, S_IFDIR, S_IFMT};
     use std::ffi::OsStr;
     use std::os::windows::io::AsRawHandle;
+    use std::path::Path;
     use std::sync::OnceLock;
     use windows_sys::Win32::Foundation::{
         ERROR_INVALID_HANDLE, ERROR_NOT_SUPPORTED, FILETIME, FreeLibrary, SetLastError,
@@ -67,21 +67,15 @@ pub mod windows {
     impl StatStruct {
         // update_st_mode_from_path in cpython
         pub fn update_st_mode_from_path(&mut self, path: &OsStr, attr: u32) {
-            if attr & FILE_ATTRIBUTE_DIRECTORY == 0 {
-                let file_extension = path
-                    .to_wide()
-                    .split(|&c| c == '.' as u16)
-                    .next_back()
-                    .and_then(|s| String::from_utf16(s).ok());
-
-                if let Some(file_extension) = file_extension
-                    && (file_extension.eq_ignore_ascii_case("exe")
-                        || file_extension.eq_ignore_ascii_case("bat")
-                        || file_extension.eq_ignore_ascii_case("cmd")
-                        || file_extension.eq_ignore_ascii_case("com"))
-                {
-                    self.st_mode |= 0o111;
-                }
+            if attr & FILE_ATTRIBUTE_DIRECTORY == 0
+                && let Some(file_extension) =
+                    Path::new(path).extension().and_then(|ext| ext.to_str())
+                && (file_extension.eq_ignore_ascii_case("exe")
+                    || file_extension.eq_ignore_ascii_case("bat")
+                    || file_extension.eq_ignore_ascii_case("cmd")
+                    || file_extension.eq_ignore_ascii_case("com"))
+            {
+                self.st_mode |= 0o111;
             }
         }
     }
@@ -288,7 +282,7 @@ pub mod windows {
 
     // _Py_GetFileInformationByName in cpython
     pub fn get_file_information_by_name(
-        file_name: &OsStr,
+        file_name: &widestring::WideCStr,
         file_information_class: FILE_INFO_BY_NAME_CLASS,
     ) -> std::io::Result<FILE_STAT_BASIC_INFORMATION> {
         static GET_FILE_INFORMATION_BY_NAME: OnceLock<
@@ -329,7 +323,6 @@ pub mod windows {
             })
             .ok_or_else(|| std::io::Error::from_raw_os_error(ERROR_NOT_SUPPORTED as _))?;
 
-        let file_name = file_name.to_wide_with_nul();
         let file_info_buffer_size = core::mem::size_of::<FILE_STAT_BASIC_INFORMATION>() as u32;
         let mut file_info_buffer = core::mem::MaybeUninit::<FILE_STAT_BASIC_INFORMATION>::uninit();
         unsafe {