irc_proto/
irc.rs

1//! Implementation of IRC codec for Tokio.
2use bytes::BytesMut;
3use tokio_util::codec::{Decoder, Encoder};
4
5use crate::error;
6use crate::line::LineCodec;
7use crate::message::Message;
8
9/// An IRC codec built around an inner codec.
10pub struct IrcCodec {
11    inner: LineCodec,
12}
13
14impl IrcCodec {
15    /// Creates a new instance of IrcCodec wrapping a LineCodec with the specific encoding.
16    pub fn new(label: &str) -> error::Result<IrcCodec> {
17        LineCodec::new(label).map(|codec| IrcCodec { inner: codec })
18    }
19
20    /// Sanitizes the input string by cutting up to (and including) the first occurence of a line
21    /// terminiating phrase (`\r\n`, `\r`, or `\n`). This is used in sending messages through the
22    /// codec to prevent the injection of additional commands.
23    pub fn sanitize(mut data: String) -> String {
24        // n.b. ordering matters here to prefer "\r\n" over "\r"
25        if let Some((pos, len)) = ["\r\n", "\r", "\n"]
26            .iter()
27            .flat_map(|needle| data.find(needle).map(|pos| (pos, needle.len())))
28            .min_by_key(|&(pos, _)| pos)
29        {
30            data.truncate(pos + len);
31        }
32        data
33    }
34}
35
36impl Decoder for IrcCodec {
37    type Item = Message;
38    type Error = error::ProtocolError;
39
40    fn decode(&mut self, src: &mut BytesMut) -> error::Result<Option<Message>> {
41        self.inner
42            .decode(src)
43            .and_then(|res| res.map_or(Ok(None), |msg| msg.parse::<Message>().map(Some)))
44    }
45}
46
47impl Encoder<Message> for IrcCodec {
48    type Error = error::ProtocolError;
49
50    fn encode(&mut self, msg: Message, dst: &mut BytesMut) -> error::Result<()> {
51        self.inner.encode(IrcCodec::sanitize(msg.to_string()), dst)
52    }
53}
irc_proto/irc.rs

irc_proto/
irc.rs
