Function get_file_information_by_name

crates/common/src/fileutils.rs:292–353

_Py_GetFileInformationByName in cpython

(
        file_name: &OsStr,
        file_information_class: FILE_INFO_BY_NAME_CLASS,
    )

    // _Py_GetFileInformationByName in cpython
    pub fn get_file_information_by_name(
        file_name: &OsStr,
        file_information_class: FILE_INFO_BY_NAME_CLASS,
    ) -> std::io::Result<FILE_STAT_BASIC_INFORMATION> {
        static GET_FILE_INFORMATION_BY_NAME: OnceLock<
            Option<
                unsafe extern "system" fn(
                    PCWSTR,
                    FILE_INFO_BY_NAME_CLASS,
                    *mut libc::c_void,
                    u32,
                ) -> i32,
            >,
        > = OnceLock::new();

        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()) };
                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()) }
                {
                    Some(unsafe {
                        core::mem::transmute::<
                            unsafe extern "system" fn() -> isize,
                            unsafe extern "system" fn(
                                *const u16,
                                FILE_INFO_BY_NAME_CLASS,
                                *mut libc::c_void,
                                u32,
                            ) -> i32,
                        >(proc)
                    })
                } else {
                    unsafe { FreeLibrary(module) };
                    None
                }
            })
            .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 {
            if GetFileInformationByName(
                file_name.as_ptr(),
                file_information_class as _,
                file_info_buffer.as_mut_ptr() as _,
                file_info_buffer_size,
            ) == 0
            {
                Err(std::io::Error::last_os_error())
            } else {