put some important constants in the 'msg' module

hptp-send/src/main.rs

@@ -5,7 +5,7 @@ extern crate tokio;
 extern crate thiserror;
 
 use hptp::log::Logger;
-use hptp::msg::Msg;
+use hptp::msg::{self, Msg};
 use hptp::peer::Peer;
 use std::net::SocketAddr;
 use tokio::io::AsyncRead;
@@ -69,12 +69,12 @@ fn parse_args(mut args: impl Iterator<Item = String>) -> Result<SocketAddr, Erro
         .map_err(|_| Error::InvalidArgs)
 }
 
-async fn read_some<IN>(inp: &mut IN) -> Result<Option<Vec<u8>>, Error>
+async fn read_data<IN>(inp: &mut IN) -> Result<Option<Vec<u8>>, Error>
 where
     IN: AsyncRead + Unpin,
 {
     use tokio::io::AsyncReadExt;
-    let mut buf = [0u8; 512];
+    let mut buf = [0u8; msg::MAX_DATA_SIZE];
     let len = inp.read(&mut buf).await?;
     Ok(if len > 0 {
         Some(buf[..len].into())
@@ -89,7 +89,7 @@ where
 {
     let mut pos = 0;
     loop {
-        match read_some(inp).await? {
+        match read_data(inp).await? {
             Some(data) => {
                 let len = data.len();
                 peer.send(Msg::Data(data)).await?;

hptp/src/msg.rs

@@ -3,6 +3,9 @@ pub enum Msg {
     Data(Vec<u8>),
 }
 
+pub const MAX_DATA_SIZE: usize = 999;
+pub const MAX_SERIALIZED_SIZE: usize = MAX_DATA_SIZE;
+
 impl Msg {
     pub fn des(data: &[u8]) -> Msg {
         Msg::Data(data.into())

hptp/src/peer.rs

@@ -1,15 +1,13 @@
 use std::net::SocketAddr;
 use tokio::net::UdpSocket;
 
-use super::msg::Msg;
+use super::msg::{self, Msg};
 
 pub struct Peer {
     sock: UdpSocket,
     targ: Option<SocketAddr>,
 }
 
-const BUFFER_SIZE: usize = 1000;
-
 impl Peer {
     pub fn new(sock: UdpSocket) -> Self {
         Peer { sock, targ: None }
@@ -31,7 +29,7 @@ impl Peer {
     }
 
     pub async fn recv(&mut self) -> Result<Msg, tokio::io::Error> {
-        let mut buf = [0u8; BUFFER_SIZE];
+        let mut buf = [0u8; msg::MAX_SERIALIZED_SIZE];
         let (len, who) = self.sock.recv_from(&mut buf).await?;
         self.set_known_target(who);
         Ok(Msg::des(&buf[..len]))