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use super::*;
use std::net;
#[derive(Debug)]
pub struct Connection {
pub conn: net::TcpStream,
pub addr: net::SocketAddr,
pub connect_timeout: core::time::Duration,
}
impl Connection {
pub fn connect_timeout(addr: &net::SocketAddr, timeout: core::time::Duration) -> Result<Self> {
Ok(Self {
conn: connect_timeout(addr, timeout)?,
addr: *addr,
connect_timeout: timeout,
})
}
pub fn exec(&mut self, command: &str, buf: &mut Vec<u8>) -> Result<()> {
use std::io::Write;
if command == "" {
buf.clear();
return Ok(());
}
if command.contains('\n') {
return Err("command contains newline".into());
}
self.conn.write_all(format!("{}\n", command).as_bytes())?;
if let Err(e) = read_message(&mut self.conn, buf) {
if *e.kind().to_string() == ErrorKind::EOF.to_string() {
self.conn = connect_timeout(&self.addr, self.connect_timeout)?;
}
return Err(e);
}
Ok(())
}
pub fn exec_eval(&mut self, command: &str, buf: &mut Vec<u8>) -> Result<()> {
if command == "" {
buf.clear();
return Ok(());
}
self.exec(format!(r#"eval "$({})\n""#, command).as_str(), buf)?;
if let Some(b) = buf.last() {
if *b == b'\\' {
buf.pop();
}
}
Ok(())
}
}
fn connect_timeout(
addr: &net::SocketAddr,
timeout: core::time::Duration,
) -> Result<net::TcpStream> {
let mut conn = net::TcpStream::connect_timeout(addr, timeout)?;
read_message(&mut conn, &mut Vec::new())?;
Ok(conn)
}
pub fn read_message(r: &mut impl std::io::Read, buf: &mut Vec<u8>) -> Result<()> {
buf.clear();
loop {
let mut b: [u8; 1] = [0];
if r.read(&mut b)? == 0 {
return Err(ErrorKind::EOF.into());
}
buf.push(b[0]);
const END_OF_MESSAGE: &str = "\n> ";
if buf.len() >= END_OF_MESSAGE.len()
&& buf.as_slice()[buf.len() - END_OF_MESSAGE.len()..] == *END_OF_MESSAGE.as_bytes()
{
buf.truncate(buf.len() - END_OF_MESSAGE.len());
if let Some(b) = buf.get(0) {
if *b == b'\n' {
buf.drain(..1);
}
}
return Ok(());
}
}
}
#[cfg(test)]
mod tests {
#[allow(unused_imports)]
use super::*;
#[test]
fn test_read_message() {
struct Test {
s: &'static [u8],
expected: &'static [u8],
expect_error: bool,
}
let tests = vec![
Test {
s: b"",
expected: b"",
expect_error: true,
},
Test {
s: b"\n",
expected: b"\n",
expect_error: true,
},
Test {
s: b"\n> ",
expected: b"",
expect_error: false,
},
Test {
s: b"a\n> ",
expected: b"a",
expect_error: false,
},
Test {
s: b"a\n> \n> ",
expected: b"a",
expect_error: false,
},
Test {
s: b"\na\n> ",
expected: b"a",
expect_error: false,
},
];
let mut buf: Vec<u8> = Vec::new();
for (i, test) in tests.iter().enumerate() {
use bytes::buf::ext::BufExt;
let result = read_message(&mut bytes::Bytes::from_static(test.s).reader(), &mut buf);
assert_eq!(result.is_err(), test.expect_error);
assert_eq!(buf.as_slice(), test.expected, "{}", i);
}
}
}