extern crate byteorder;
extern crate mio;
use crate::buffer::NetworkBuffer;
use crate::Error;
use byteorder::{NetworkEndian, ReadBytesExt, WriteBytesExt};
use std::any::Any;
use std::io::Cursor;
pub const PACKET_HEADER_SIZE: usize = 3; pub const MAX_PACKET_BODY_SIZE: usize = 8192;
pub const MAX_PACKET_SIZE: usize = PACKET_HEADER_SIZE + MAX_PACKET_BODY_SIZE;
#[derive(Clone)]
pub struct PacketHeader {
pub size: u16,
pub id: u8,
}
pub trait PacketBody: Any + Send + Sync {
fn box_clone(&self) -> Box<dyn PacketBody>;
fn serialize(&self) -> Result<Vec<u8>, Error>;
fn deserialize(data: &[u8]) -> Result<Self, Error>
where
Self: Sized;
fn id(&self) -> u8;
}
impl Clone for Box<dyn PacketBody> {
fn clone(&self) -> Box<dyn PacketBody> {
self.box_clone()
}
}
#[derive(Clone)]
pub struct Packet {
pub header: PacketHeader,
pub body: Vec<u8>,
}
pub fn serialize_packet(body: Box<dyn PacketBody>) -> Result<Vec<u8>, Error> {
let mut body_data: Vec<u8> = body.serialize()?;
let mut data: Vec<u8> = Vec::new();
data.write_u16::<NetworkEndian>(body_data.len() as u16)?;
data.write_u8(body.id())?;
data.append(&mut body_data);
Ok(data)
}
pub fn deserialize_packet_header(buffer: &mut NetworkBuffer) -> Result<PacketHeader, Error> {
let mut reader = Cursor::new(&buffer.data[..]);
let body_size = reader.read_u16::<NetworkEndian>()? as usize;
if body_size >= MAX_PACKET_BODY_SIZE {
eprintln!(
"Packet body is {} bytes, but max body size is ({} bytes)!",
body_size, MAX_PACKET_BODY_SIZE
);
return Err(Error::InvalidData);
}
let packet_id = reader.read_u8()?;
let header = PacketHeader {
size: body_size as u16,
id: packet_id,
};
Ok(header)
}