mqtt_codec_kit/common/variable_header/
packet_identifier.rs

1use std::io::{self, Read, Write};
2
3use byteorder::{BigEndian, ReadBytesExt, WriteBytesExt};
4
5use crate::common::{Decodable, Encodable};
6
7/// Packet identifier
8#[derive(Debug, Eq, PartialEq, Copy, Clone)]
9pub struct PacketIdentifier(pub u16);
10
11impl Encodable for PacketIdentifier {
12    fn encode<W: Write>(&self, writer: &mut W) -> Result<(), io::Error> {
13        writer.write_u16::<BigEndian>(self.0)
14    }
15
16    fn encoded_length(&self) -> u32 {
17        2
18    }
19}
20
21impl Decodable for PacketIdentifier {
22    type Error = io::Error;
23    type Cond = ();
24
25    fn decode_with<R: Read>(reader: &mut R, _rest: ()) -> Result<PacketIdentifier, io::Error> {
26        reader
27            .read_u16::<BigEndian>()
28            .map(PacketIdentifier)
29            .map_err(From::from)
30    }
31}