Remove usage of vmsplice from yes

Addresses issue #7625
Remove the usage of vmsplice from `yes` utility since it can cause
errors.

src/uu/yes/src/splice.rs

@@ -1,77 +0,0 @@
-// This file is part of the uutils coreutils package.
-//
-// For the full copyright and license information, please view the LICENSE
-// file that was distributed with this source code.
-//! On Linux we can use vmsplice() to write data more efficiently.
-//!
-//! This does not always work. We're not allowed to splice to some targets,
-//! and on some systems (notably WSL 1) it isn't supported at all.
-//!
-//! If we get an error code that suggests splicing isn't supported then we
-//! tell that to the caller so it can fall back to a robust naïve method. If
-//! we get another kind of error we bubble it up as normal.
-//!
-//! vmsplice() can only splice into a pipe, so if the output is not a pipe
-//! we make our own and use splice() to bridge the gap from the pipe to the
-//! output.
-//!
-//! We assume that an "unsupported" error will only ever happen before any
-//! data was successfully written to the output. That way we don't have to
-//! make any effort to rescue data from the pipe if splice() fails, we can
-//! just fall back and start over from the beginning.
-
-use std::{
-    io,
-    os::fd::{AsFd, AsRawFd},
-};
-
-use nix::{errno::Errno, libc::S_IFIFO, sys::stat::fstat};
-
-use uucore::pipes::{pipe, splice_exact, vmsplice};
-
-pub(crate) fn splice_data<T>(bytes: &[u8], out: &T) -> Result<()>
-where
-    T: AsRawFd + AsFd,
-{
-    let is_pipe = fstat(out.as_raw_fd())?.st_mode as nix::libc::mode_t & S_IFIFO != 0;
-
-    if is_pipe {
-        loop {
-            let mut bytes = bytes;
-            while !bytes.is_empty() {
-                let len = vmsplice(out, bytes).map_err(maybe_unsupported)?;
-                bytes = &bytes[len..];
-            }
-        }
-    } else {
-        let (read, write) = pipe()?;
-        loop {
-            let mut bytes = bytes;
-            while !bytes.is_empty() {
-                let len = vmsplice(&write, bytes).map_err(maybe_unsupported)?;
-                splice_exact(&read, out, len).map_err(maybe_unsupported)?;
-                bytes = &bytes[len..];
-            }
-        }
-    }
-}
-
-pub(crate) enum Error {
-    Unsupported,
-    Io(io::Error),
-}
-
-type Result<T> = std::result::Result<T, Error>;
-
-impl From<nix::Error> for Error {
-    fn from(error: nix::Error) -> Self {
-        Self::Io(io::Error::from_raw_os_error(error as i32))
-    }
-}
-
-fn maybe_unsupported(error: nix::Error) -> Error {
-    match error {
-        Errno::EINVAL | Errno::ENOSYS | Errno::EBADF => Error::Unsupported,
-        _ => error.into(),
-    }
-}

src/uu/yes/src/yes.rs

@@ -9,14 +9,10 @@ use clap::{Arg, ArgAction, Command, builder::ValueParser};
 use std::error::Error;
 use std::ffi::OsString;
 use std::io::{self, Write};
-#[cfg(any(target_os = "linux", target_os = "android"))]
-use std::os::fd::AsFd;
 use uucore::error::{UResult, USimpleError};
 #[cfg(unix)]
 use uucore::signals::enable_pipe_errors;
 use uucore::{format_usage, help_about, help_usage};
-#[cfg(any(target_os = "linux", target_os = "android"))]
-mod splice;
 
 const ABOUT: &str = help_about!("yes.md");
 const USAGE: &str = help_usage!("yes.md");
@@ -118,15 +114,6 @@ pub fn exec(bytes: &[u8]) -> io::Result<()> {
     #[cfg(unix)]
     enable_pipe_errors()?;
 
-    #[cfg(any(target_os = "linux", target_os = "android"))]
-    {
-        match splice::splice_data(bytes, &stdout.as_fd()) {
-            Ok(_) => return Ok(()),
-            Err(splice::Error::Io(err)) => return Err(err),
-            Err(splice::Error::Unsupported) => (),
-        }
-    }
-
     loop {
         stdout.write_all(bytes)?;
     }