cleanup and target list #2
cargo devel CI / cargo CI (push) Successful in 22s Details

This commit is contained in:
Christoph J. Scherr 2024-02-21 22:31:15 +01:00
parent efdf9a42e6
commit 15d6a1d2e1
Signed by: PlexSheep
GPG Key ID: 7CDD0B14851A08EF
1 changed files with 27 additions and 15 deletions

View File

@ -5,32 +5,44 @@ const BUFSIZ: usize = 2 << 8;
fn main() -> Result<(), io::Error> {
// /dev/tty points the currently opened terminal. If we write to it directly, we bypass piping
// to the next process
let mut tty = std::fs::File::options()
let tty = std::fs::File::options()
.write(true)
.read(false)
// try to use $TTY set by the terminal, otherwise use the default tty
.open(std::env::var("TTY").unwrap_or(String::from(TTY)))
.inspect_err(|err| eprintln!("could not open tty: {err}"))?;
// we want to write to the stdout too
let mut stdout = io::stdout();
// sadly, we need to store the content of `stdin` in a buffer and cannot just `io::copy()` it
// multiple times. `tee` from the GNU coreutils does this too.
// fill our targets
// any file or stream that we want our stdin to go to can be a target. The only condition is
// that we can write to it.
let mut targets: Vec<Box<dyn Write>> = vec![Box::new(tty), Box::new(io::stdout())];
// fill the buffer with data from stdin, then write the read data to all targets
let mut buf = [0; BUFSIZ];
let mut stdin = io::stdin();
let mut read_amount = buf.len();
while read_amount == buf.len() {
// first we read data from the stdin
read_amount = stdin.read(&mut buf).inspect_err(|err| eprintln!("{err}"))?;
// now we just write to our targets
tty.write_all(&buf[..read_amount])
.inspect_err(|err| eprintln!("{err}"))?;
stdout
// now we just write it to our targets
for target in targets.iter_mut() {
target
.write_all(&buf[..read_amount])
.inspect_err(|err| eprintln!("{err}"))?;
}
tty.write(b"\n").inspect_err(|err| eprintln!("{err}"))?; // otherwise weird wrapped together
// lines may happen
tty.flush().inspect_err(|err| eprintln!("{err}"))?; // make sure it comes there
stdout.flush().inspect_err(|err| eprintln!("{err}"))?; // make sure it comes there
}
// append a newline to the tty
// otherwise weird wrapped together lines may happen
targets[0]
.write(b"\n")
.inspect_err(|err| eprintln!("{err}"))?;
// flush all targets
for target in targets.iter_mut() {
target.flush().inspect_err(|err| eprintln!("{err}"))?; // make sure it comes there
}
Ok(())
}