use std::io;use std::path::Path;pub(crate) async fn open(path: &Path) -> io::Result<tokio::fs::File> {    let mut options = tokio::fs::OpenOptions::new();    options.read(true);    configure_open(&mut options);    let file = options.open(path).await?;    if !is_disk_file(&file) || !file.metadata().await?.is_file() {        return Err(io::Error::new(            io::ErrorKind::InvalidInput,            format!("path `{}` is not a file", path.display()),        ));    }    Ok(file)}#[cfg(unix)]fn configure_open(options: &mut tokio::fs::OpenOptions) {    options.custom_flags(libc::O_NONBLOCK);}#[cfg(windows)]fn configure_open(options: &mut tokio::fs::OpenOptions) {    use windows_sys::Win32::Storage::FileSystem::SECURITY_IDENTIFICATION;    options.security_qos_flags(SECURITY_IDENTIFICATION);}#[cfg(not(any(unix, windows)))]fn configure_open(_options: &mut tokio::fs::OpenOptions) {}#[cfg(windows)]fn is_disk_file(file: &tokio::fs::File) -> bool {    use std::os::windows::io::AsRawHandle;    use windows_sys::Win32::Foundation::HANDLE;    use windows_sys::Win32::Storage::FileSystem::FILE_TYPE_DISK;    use windows_sys::Win32::Storage::FileSystem::GetFileType;    // SAFETY: `file` owns this handle for the duration of the call.    unsafe { GetFileType(file.as_raw_handle() as HANDLE) == FILE_TYPE_DISK }}#[cfg(not(windows))]fn is_disk_file(_file: &tokio::fs::File) -> bool {    true}