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Merged
youknowone merged 1 commit into from
Aug 9, 2026
Merged

Use C string literals and w! instead of allocs #8474

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18 changes: 8 additions & 10 deletions crates/host_env/src/fileutils.rs
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Original file line number Diff line number Diff line change
@@ -1,6 +1,8 @@
// Python/fileutils.c in CPython
#![allow(non_snake_case)]

use alloc::ffi::CString;

#[cfg(not(windows))]
pub use rustix::fs::Stat as StatStruct;

Expand All @@ -16,9 +18,8 @@ pub fn fstat(fd: crate::crt_fd::Borrowed<'_>) -> std::io::Result<StatStruct> {
pub mod windows {
use crate::crt_fd;
use crate::windows::ToWideString;
use alloc::ffi::CString;
use libc::{S_IFCHR, S_IFDIR, S_IFMT};
use std::ffi::{OsStr, OsString};
use std::ffi::OsStr;
use std::os::windows::io::AsRawHandle;
use std::sync::OnceLock;
use windows_sys::Win32::Foundation::{
Expand All @@ -33,6 +34,7 @@ pub mod windows {
use windows_sys::Win32::System::LibraryLoader::{GetProcAddress, LoadLibraryW};
use windows_sys::Win32::System::SystemServices::IO_REPARSE_TAG_SYMLINK;
use windows_sys::core::PCWSTR;
use windows_sys::w;

pub const S_IFIFO: libc::c_int = 0o010000;
pub const S_IFLNK: libc::c_int = 0o120000;
Expand Down Expand Up @@ -302,16 +304,13 @@ pub mod windows {

let GetFileInformationByName = GET_FILE_INFORMATION_BY_NAME
.get_or_init(|| {
let library_name =
OsString::from("api-ms-win-core-file-l2-1-4.dll").to_wide_with_nul();
let module = unsafe { LoadLibraryW(library_name.as_ptr()) };
let library_name = w!("api-ms-win-core-file-l2-1-4.dll");
let module = unsafe { LoadLibraryW(library_name) };
if module.is_null() {
return None;
}
let name = CString::new("GetFileInformationByName").unwrap();
if let Some(proc) =
unsafe { GetProcAddress(module, name.as_bytes_with_nul().as_ptr()) }
{
let name = c"GetFileInformationByName";
if let Some(proc) = unsafe { GetProcAddress(module, name.as_ptr().cast()) } {
Some(unsafe {
core::mem::transmute::<
unsafe extern "system" fn() -> isize,
Expand Down Expand Up @@ -458,7 +457,6 @@ pub unsafe fn fclose(fp: *mut CFile) -> core::ffi::c_int {
reason = "false positive: core::io::ErrorKind is unstable (core_io)"
)]
pub fn fopen(path: &std::path::Path, mode: &str) -> std::io::Result<*mut CFile> {
use alloc::ffi::CString;
use std::fs::File;

// Currently only supports read mode
Expand Down
37 changes: 19 additions & 18 deletions crates/host_env/src/nt.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -22,19 +22,22 @@ use crate::{
windows::{CheckWin32Bool, CheckWin32Handle, CheckWin32Sentinel, HandleToOwned, ToWideString},
};
use libc::intptr_t;
use windows_sys::Win32::{
Foundation::{
CloseHandle, ERROR_INVALID_HANDLE, GetLastError, HANDLE, INVALID_HANDLE_VALUE, MAX_PATH,
},
Globalization::{CP_UTF8, MultiByteToWideChar, WideCharToMultiByte},
Storage::FileSystem::{
CreateFileW, FILE_BASIC_INFO, FILE_FLAG_BACKUP_SEMANTICS, FILE_FLAG_OPEN_REPARSE_POINT,
FILE_READ_ATTRIBUTES, FILE_TYPE_UNKNOWN, FileBasicInfo, FindClose, FindFirstFileW,
GetFileAttributesW, GetFileInformationByHandleEx, GetFileType, GetFullPathNameW,
INVALID_FILE_ATTRIBUTES, OPEN_EXISTING, SetFileAttributesW, SetFileInformationByHandle,
WIN32_FIND_DATAW,
use windows_sys::{
Win32::{
Foundation::{
CloseHandle, ERROR_INVALID_HANDLE, GetLastError, HANDLE, INVALID_HANDLE_VALUE, MAX_PATH,
},
Globalization::{CP_UTF8, MultiByteToWideChar, WideCharToMultiByte},
Storage::FileSystem::{
CreateFileW, FILE_BASIC_INFO, FILE_FLAG_BACKUP_SEMANTICS, FILE_FLAG_OPEN_REPARSE_POINT,
FILE_READ_ATTRIBUTES, FILE_TYPE_UNKNOWN, FileBasicInfo, FindClose, FindFirstFileW,
GetFileAttributesW, GetFileInformationByHandleEx, GetFileType, GetFullPathNameW,
INVALID_FILE_ATTRIBUTES, OPEN_EXISTING, SetFileAttributesW, SetFileInformationByHandle,
WIN32_FIND_DATAW,
},
System::{Console, Threading},
},
System::{Console, Threading},
w,
};

pub type Handle = HANDLE;
Expand Down Expand Up @@ -1172,12 +1175,10 @@ pub fn mkdir(path: &widestring::WideCStr, mode: i32) -> io::Result<()> {
lpSecurityDescriptor: core::ptr::null_mut(),
bInheritHandle: 0,
};
let sddl: Vec<u16> = "D:P(A;OICI;FA;;;SY)(A;OICI;FA;;;BA)(A;OICI;FA;;;OW)\0"
.encode_utf16()
.collect();
let sddl = w!("D:P(A;OICI;FA;;;SY)(A;OICI;FA;;;BA)(A;OICI;FA;;;OW)");
unsafe {
ConvertStringSecurityDescriptorToSecurityDescriptorW(
sddl.as_ptr(),
sddl,
SDDL_REVISION_1,
&mut sec_attr.lpSecurityDescriptor,
core::ptr::null_mut(),
Expand Down Expand Up @@ -1699,10 +1700,10 @@ pub fn get_terminal_size_handle(h: HANDLE) -> io::Result<(usize, usize)> {
if err != windows_sys::Win32::Foundation::ERROR_ACCESS_DENIED {
return Err(io::Error::last_os_error());
}
let conout: Vec<u16> = "CONOUT$\0".encode_utf16().collect();
let conout = w!("CONOUT$");
let console_handle = unsafe {
CreateFileW(
conout.as_ptr(),
conout,
windows_sys::Win32::Foundation::GENERIC_READ
| windows_sys::Win32::Foundation::GENERIC_WRITE,
windows_sys::Win32::Storage::FileSystem::FILE_SHARE_READ
Expand Down
5 changes: 3 additions & 2 deletions crates/host_env/src/winapi.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -65,6 +65,7 @@ pub use windows_sys::Win32::{
},
UI::WindowsAndMessaging::SW_HIDE,
};
use windows_sys::w;

pub type Handle = HANDLE;
pub type StdHandle = windows_sys::Win32::System::Console::STD_HANDLE;
Expand Down Expand Up @@ -1093,14 +1094,14 @@ where
return Err(MimeRegistryReadError::Os(err));
}

let content_type_key: Vec<u16> = "Content Type\0".encode_utf16().collect();
let content_type_key = w!("Content Type");
let mut type_buf = [0u16; 256];
let mut cb_type = (type_buf.len() * 2) as u32;
let mut reg_type = 0;
let err = unsafe {
RegQueryValueExW(
subkey,
content_type_key.as_ptr(),
content_type_key,
core::ptr::null_mut(),
&mut reg_type,
type_buf.as_mut_ptr().cast(),
Expand Down
43 changes: 23 additions & 20 deletions crates/host_env/src/windows.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -4,24 +4,27 @@ use std::{
io,
os::windows::ffi::{OsStrExt, OsStringExt},
};
use windows_sys::Win32::{
Foundation::{
E_POINTER, ERROR_INSUFFICIENT_BUFFER, ERROR_INVALID_FLAGS, ERROR_NO_UNICODE_TRANSLATION,
MAX_PATH, S_OK,
},
Networking::WinSock::WSAStartup,
Storage::FileSystem::{
GetFileVersionInfoSizeW, GetFileVersionInfoW, VS_FIXEDFILEINFO, VerQueryValueW,
},
System::{
Diagnostics::Debug::{
FORMAT_MESSAGE_ALLOCATE_BUFFER, FORMAT_MESSAGE_FROM_SYSTEM,
FORMAT_MESSAGE_IGNORE_INSERTS, FormatMessageW,
use windows_sys::{
Win32::{
Foundation::{
E_POINTER, ERROR_INSUFFICIENT_BUFFER, ERROR_INVALID_FLAGS,
ERROR_NO_UNICODE_TRANSLATION, MAX_PATH, S_OK,
},
Networking::WinSock::WSAStartup,
Storage::FileSystem::{
GetFileVersionInfoSizeW, GetFileVersionInfoW, VS_FIXEDFILEINFO, VerQueryValueW,
},
System::{
Diagnostics::Debug::{
FORMAT_MESSAGE_ALLOCATE_BUFFER, FORMAT_MESSAGE_FROM_SYSTEM,
FORMAT_MESSAGE_IGNORE_INSERTS, FormatMessageW,
},
LibraryLoader::{GetModuleFileNameW, GetModuleHandleW},
SystemInformation::{GetVersionExW, OSVERSIONINFOEXW, OSVERSIONINFOW},
Threading::{GetCurrentThreadStackLimits, SetThreadStackGuarantee},
},
LibraryLoader::{GetModuleFileNameW, GetModuleHandleW},
SystemInformation::{GetVersionExW, OSVERSIONINFOEXW, OSVERSIONINFOW},
Threading::{GetCurrentThreadStackLimits, SetThreadStackGuarantee},
},
w,
};

/// _MAX_ENV from Windows CRT stdlib.h - maximum environment variable size
Expand Down Expand Up @@ -154,8 +157,8 @@ pub struct WindowsVersionInfo {

fn get_kernel32_version() -> io::Result<(u32, u32, u32)> {
unsafe {
let module_name: Vec<u16> = OsStr::new("kernel32.dll").to_wide_with_nul();
let h_kernel32 = GetModuleHandleW(module_name.as_ptr()).check_nonnull()?;
let module_name = w!("kernel32.dll");
let h_kernel32 = GetModuleHandleW(module_name).check_nonnull()?;

let mut kernel32_path = [0u16; MAX_PATH as usize];
let len = GetModuleFileNameW(
Expand All @@ -181,13 +184,13 @@ fn get_kernel32_version() -> io::Result<(u32, u32, u32)> {
)
.check_win32_bool()?;

let sub_block: Vec<u16> = OsStr::new("").to_wide_with_nul();
let sub_block = w!("");

let mut ffi_ptr: *mut VS_FIXEDFILEINFO = core::ptr::null_mut();
let mut ffi_len: u32 = 0;
VerQueryValueW(
ver_block.as_ptr() as *const _,
sub_block.as_ptr(),
sub_block,
&mut ffi_ptr as *mut *mut VS_FIXEDFILEINFO as *mut *mut _,
&mut ffi_len as *mut u32,
)
Expand Down
24 changes: 12 additions & 12 deletions crates/host_env/src/wmi.rs
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Original file line number Diff line number Diff line change
Expand Up @@ -7,15 +7,17 @@

use core::ffi::c_void;
use core::ptr::{NonNull, null, null_mut};
use widestring::WideCString;
use windows_sys::Win32::Foundation::{
CloseHandle, ERROR_BROKEN_PIPE, ERROR_MORE_DATA, ERROR_NOT_ENOUGH_MEMORY, GetLastError, HANDLE,
WAIT_OBJECT_0, WAIT_TIMEOUT,
CloseHandle, ERROR_BROKEN_PIPE, ERROR_INVALID_NAME, ERROR_MORE_DATA, ERROR_NOT_ENOUGH_MEMORY,
GetLastError, HANDLE, WAIT_OBJECT_0, WAIT_TIMEOUT,
};
use windows_sys::Win32::Storage::FileSystem::{ReadFile, WriteFile};
use windows_sys::Win32::System::Pipes::CreatePipe;
use windows_sys::Win32::System::Threading::{
CreateEventW, CreateThread, GetExitCodeThread, SetEvent, WaitForSingleObject,
};
use windows_sys::w;

use crate::ctypes::wcslen;

Expand Down Expand Up @@ -256,10 +258,6 @@ const fn failed(hr: HRESULT) -> bool {
hr < 0
}

fn wide_str(s: &str) -> Vec<u16> {
s.encode_utf16().chain(core::iter::once(0)).collect()
}

unsafe fn wait_event(event: HANDLE, timeout: u32) -> u32 {
match unsafe { WaitForSingleObject(event, timeout) } {
WAIT_OBJECT_0 => 0,
Expand Down Expand Up @@ -346,8 +344,8 @@ unsafe fn query_thread_impl(param: *mut c_void) -> u32 {
}

if succeeded(hr) {
let root_cimv2 = wide_str("ROOT\\CIMV2");
let bstr_root = unsafe { SysAllocString(root_cimv2.as_ptr()) };
let root_cimv2 = w!("ROOT\\CIMV2");
let bstr_root = unsafe { SysAllocString(root_cimv2) };
hr = unsafe {
locator_connect_server(
locator,
Expand Down Expand Up @@ -384,8 +382,8 @@ unsafe fn query_thread_impl(param: *mut c_void) -> u32 {
};
}
if succeeded(hr) {
let wql = wide_str("WQL");
let bstr_wql = unsafe { SysAllocString(wql.as_ptr()) };
let wql = w!("WQL");
let bstr_wql = unsafe { SysAllocString(wql) };
hr = unsafe {
services_exec_query(
services,
Expand Down Expand Up @@ -557,7 +555,9 @@ unsafe fn query_thread_impl(param: *mut c_void) -> u32 {
}

pub fn exec_query(query_str: &str) -> Result<String, ExecQueryError> {
let query_wide = wide_str(query_str);
let query = WideCString::from_str(query_str)
.map_err(|_| ExecQueryError::Code(ERROR_INVALID_NAME))?
.into();
Comment on lines +558 to +560

@coderabbitai coderabbitai Bot Aug 9, 2026

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🩺 Stability & Availability | 🔴 Critical | ⚡ Quick win

🧩 Analysis chain

🏁 Script executed:

#!/usr/bin/env bash
set -euo pipefail

cargo tree -i widestring --edges normal
rg -n 'WideCString::from_str|into_vec(_with_nul)?|SysAllocString|struct QueryThreadData' \
  crates/host_env/src/wmi.rs Cargo.toml Cargo.lock

Repository: RustPython/RustPython

Length of output: 1110

🏁 Script executed:

#!/usr/bin/env bash
set -euo pipefail

sed -n '240,310p' crates/host_env/src/wmi.rs
printf '\n--- 540-590 ---\n'
sed -n '540,590p' crates/host_env/src/wmi.rs

printf '\n--- Widestring references in Cargo.lock ---\n'
rg -n 'name = "widestring"|version = "1\.' Cargo.lock || true

printf '\n--- Source docs from local wide string crate if present ---\n'
fd -a 'ucstring.rs|widestring' Cargo.lock .cargo registry 2>/dev/null | head -20

Repository: RustPython/RustPython

Length of output: 6019

🌐 Web query:

widestring 1.2.1 U16CString into_vec into_vec_with_nul documentation

💡 Result:

In the widestring crate, U16CString is an owned, mutable, nul-terminated 16-bit wide string designed for FFI [1][2][3]. The methods into_vec and into_vec_with_nul are used to consume the U16CString and convert it into a standard Rust Vec [1][4]. into_vec Converts the U16CString into a Vec without a nul terminator [1][4]. The resulting vector will contain no nul values [1]. into_vec_with_nul Converts the U16CString into a Vec including the terminating nul character [1][4]. The resulting vector will contain a nul-terminator at the end and no interior nul values [1][4]. Example usage: use widestring::U16CString; let wcstr = U16CString::from_str("example").unwrap; // Convert to Vec without nul terminator let v = wcstr.into_vec; assert_eq!(v, vec!); // Convert to Vec with nul terminator let wcvec = wcstr.into_vec_with_nul; assert_eq!(wcvec[wcvec.len-1], 0);

Citations:

Retain the WMI query NUL terminator before calling SysAllocString.

QueryThreadData.query: Vec<u16> is passed to SysAllocString(data.query.as_ptr()), so query_vec must include the terminating u16. WideCString::into() drops it via U16CString::<u16>::into_vec(); use into_vec_with_nul() when converting the WQL query string.

Also applies to the WQL Bstr construction at line 386.

🤖 Prompt for AI Agents 
Verify each finding against current code. Fix only still-valid issues, skip the
rest with a brief reason, keep changes minimal, and validate.

In `@crates/host_env/src/wmi.rs` around lines 558 - 560, Update the WQL query
conversions in the affected query path and the WQL BSTR construction to call
WideCString::into_vec_with_nul() rather than into_vec(), preserving the
terminating u16 required by SysAllocString through QueryThreadData.query.


let mut h_thread: HANDLE = null_mut();
let mut err: u32 = 0;
Expand All @@ -579,7 +579,7 @@ pub fn exec_query(query_str: &str) -> Result<String, ExecQueryError> {
err = GetLastError();
} else {
let thread_data = Box::new(QueryThreadData {
query: query_wide,
query,
write_pipe,
init_event,
connect_event,
Expand Down
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