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use std::mem;
use std::net::{SocketAddr, ToSocketAddrs};
use std::fmt;
use mio::udp::UdpSocket;
use mio::{Token, EventLoop, Handler, EventSet, PollOpt};
use rand::Rng;
use rand;
use ::error::*;
use client::ClientConnection;
const RESPONSE: Token = Token(0);
pub struct UdpClientConnection {
name_server: SocketAddr,
socket: Option<UdpSocket>,
event_loop: EventLoop<Response>,
}
impl UdpClientConnection {
fn next_bound_local_address() -> ClientResult<UdpSocket> {
let mut rand = rand::thread_rng();
let mut error = Err(ClientErrorKind::Message("could not bind address in 10 tries").into());
for _ in 0..10 {
let zero_addr = ("0.0.0.0", rand.gen_range(1025_u16, u16::max_value())).to_socket_addrs().expect("could not parse 0.0.0.0 address").
next().expect("no addresses parsed from 0.0.0.0");
match UdpSocket::bound(&zero_addr) {
Ok(socket) => return Ok(socket),
Err(err) => error = Err(err.into()),
}
}
error
}
pub fn new(name_server: SocketAddr) -> ClientResult<Self> {
let socket = try!(Self::next_bound_local_address());
let mut event_loop: EventLoop<Response> = try!(EventLoop::new());
if event_loop.timeout_ms((), 5000).is_err() { return Err(ClientErrorKind::Message("error setting timer").into()) };
try!(event_loop.register(&socket, RESPONSE, EventSet::readable(), PollOpt::all()));
debug!("client event_loop created");
Ok(UdpClientConnection{name_server: name_server, socket: Some(socket), event_loop: event_loop})
}
}
impl ClientConnection for UdpClientConnection {
fn send(&mut self, buffer: Vec<u8>) -> ClientResult<Vec<u8>> {
debug!("client reregistering");
try!(self.event_loop.reregister(self.socket.as_ref().expect("never none 86"), RESPONSE, EventSet::readable(), PollOpt::all()));
debug!("client sending");
try!(self.socket.as_ref().expect("never none 88").send_to(&buffer, &self.name_server));
debug!("client sent data");
let mut response: Response = Response::new(mem::replace(&mut self.socket, None).expect("never none 92"));
try!(self.event_loop.run(&mut response));
debug!("client event_loop running");
if response.error.is_some() { return Err(response.error.unwrap()) }
if response.buf.is_none() { return Err(ClientErrorKind::Message("no data was received from the remote").into()) }
let result = Ok(response.buf.unwrap());
self.socket = Some(response.socket);
result
}
}
impl fmt::Debug for UdpClientConnection {
fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "UdpClientConnection ns: {:?} socket: {:?}", self.name_server, self.socket)
}
}
struct Response {
pub buf: Option<Vec<u8>>,
pub addr: Option<SocketAddr>,
pub error: Option<ClientError>,
pub socket: UdpSocket,
}
impl Response {
pub fn new(socket: UdpSocket) -> Self {
Response{ buf: None, addr: None, error: None, socket: socket }
}
}
impl Handler for Response {
type Timeout = ();
type Message = ();
fn ready(&mut self, event_loop: &mut EventLoop<Self>, token: Token, events: EventSet) {
match token {
RESPONSE => {
if !events.is_readable() {
debug!("got woken up, but not readable: {:?}", token);
return
}
let mut buf: [u8; 4096] = [0u8; 4096];
let recv_result = self.socket.recv_from(&mut buf);
if recv_result.is_err() {
debug!("could not recv_from on {:?}: {:?}", self.socket, recv_result);
self.error = Some(recv_result.unwrap_err().into());
return
}
if recv_result.as_ref().unwrap().is_none() {
debug!("no return address on recv_from: {:?}", self.socket);
self.error = Some(ClientErrorKind::Message("no address received in response").into());
return
}
let (length, addr) = recv_result.unwrap().unwrap();
debug!("bytes: {:?} from: {:?}", length, addr);
self.addr = Some(addr);
if length == 0 {
debug!("0 bytes recieved from: {}", addr);
return
}
event_loop.shutdown();
self.buf = Some(buf.iter().take(length).cloned().collect());
},
_ => {
error!("unrecognized token: {:?}", token);
self.error = Some(ClientErrorKind::Message("no data was received from the remote").into());
},
}
}
fn timeout(&mut self, event_loop: &mut EventLoop<Self>, _: ()) {
self.error = Some(ClientErrorKind::Message("timed out awaiting response from server(s)").into());
event_loop.shutdown();
}
}