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#[macro_use]
extern crate serde_derive;
extern crate serde_cbor;
extern crate byteorder;
use std::io::{Read, Cursor, Error};
use byteorder::{BigEndian, WriteBytesExt, ReadBytesExt};
pub struct Hdr {
pub mlen: u32,
pub key: u64,
}
#[derive(Serialize, Deserialize, Debug)]
pub struct Msg {
pub uid: String,
pub channel: String,
pub message: Vec<u8>,
}
pub fn message_encode(msg: &Msg) -> Vec<u8> {
let encoded = serde_cbor::to_vec(msg);
match encoded {
Ok(encoded) => encoded,
Err(err) => {
println!("Error on encode: {}", err);
Vec::new()
}
}
}
pub fn message_decode(slice: &[u8]) -> Msg {
let value = serde_cbor::from_slice(slice);
match value {
Ok(value) => value,
Err(err) => {
println!("Error on decode: {}", err);
Msg { uid: "".to_string(), channel: "".to_string(), message: Vec::new() }
}
}
}
pub fn read_n<R>(reader: R, bytes_to_read: u64) -> (Result<usize, Error>, Vec<u8>)
where R: Read,
{
let mut buf = vec![];
let mut chunk = reader.take(bytes_to_read);
let status = chunk.read_to_end(&mut buf);
(status, buf)
}
pub fn read_hdr_type(hdr: &[u8]) -> u32 {
let mut buf = Cursor::new(&hdr[..]);
let num = buf.read_u32::<BigEndian>().unwrap();
num >> 24
}
pub fn read_hdr_len(hdr: &[u8]) -> usize {
let mut buf = Cursor::new(&hdr[..]);
let num = buf.read_u32::<BigEndian>().unwrap();
(num & 0xfff) as usize
}
pub fn write_hdr(len: usize) -> Vec<u8> {
let hdr = (('M' as u32) << 24) | len as u32;
let mut msgv = vec![];
msgv.write_u32::<BigEndian>(hdr).unwrap();
msgv
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn test_encode_decode_msg() {
let orig_msg = Msg { uid: "User".to_string(), channel: "Channel".to_string(), message: "a test msg".to_string().into_bytes() };
let cbor_msg = message_encode(&orig_msg);
let decoded_msg = message_decode(&cbor_msg);
assert_eq!(decoded_msg.uid, orig_msg.uid);
assert_eq!(decoded_msg.channel, orig_msg.channel);
assert_eq!(decoded_msg.message, orig_msg.message);
}
}