use super::IOStream;
use crate::disc::DiscTitle;
use std::io::{self, Read, Write};
pub struct StdioStream {
disc_title: DiscTitle,
reader: Option<io::Stdin>,
writer: Option<io::Stdout>,
}
impl StdioStream {
pub fn input() -> Self {
Self {
disc_title: DiscTitle::empty(),
reader: Some(io::stdin()),
writer: None,
}
}
pub fn output() -> Self {
Self {
disc_title: DiscTitle::empty(),
reader: None,
writer: Some(io::stdout()),
}
}
pub fn meta(mut self, dt: &DiscTitle) -> Self {
self.disc_title = dt.clone();
self
}
}
impl IOStream for StdioStream {
fn info(&self) -> &DiscTitle {
&self.disc_title
}
fn finish(&mut self) -> io::Result<()> {
if let Some(ref mut w) = self.writer {
w.flush()?;
}
Ok(())
}
}
impl Read for StdioStream {
fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
match self.reader {
Some(ref mut r) => r.read(buf),
None => Err(io::Error::new(
io::ErrorKind::Unsupported,
"stdio:// opened for output — cannot read",
)),
}
}
}
impl Write for StdioStream {
fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
match self.writer {
Some(ref mut w) => w.write(buf),
None => Err(io::Error::new(
io::ErrorKind::Unsupported,
"stdio:// opened for input — cannot write",
)),
}
}
fn flush(&mut self) -> io::Result<()> {
match self.writer {
Some(ref mut w) => w.flush(),
None => Ok(()),
}
}
}
#[cfg(test)]
mod tests {
use super::*;
use std::io::{Read, Write};
#[test]
fn stdio_output_write_errors_on_read() {
let mut stream = StdioStream::output();
let mut buf = [0u8; 10];
let err = stream.read(&mut buf).unwrap_err();
assert_eq!(err.kind(), io::ErrorKind::Unsupported);
assert!(err.to_string().contains("cannot read"), "got: {}", err);
}
#[test]
fn stdio_input_read_errors_on_write() {
let mut stream = StdioStream::input();
let err = stream.write(&[0u8; 10]).unwrap_err();
assert_eq!(err.kind(), io::ErrorKind::Unsupported);
assert!(err.to_string().contains("cannot write"), "got: {}", err);
}
#[test]
fn stdio_total_bytes_returns_none() {
let input = StdioStream::input();
assert_eq!(input.total_bytes(), None);
let output = StdioStream::output();
assert_eq!(output.total_bytes(), None);
}
}