lookaround/src/server.rs

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2.2 KiB
Rust
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use crate::prelude::*;
pub async fn server <I: Iterator <Item=String>> (mut args: I) -> Result <(), AppError>
{
let common_params = app_common::Params::default ();
let mut bind_addr = "0.0.0.0".to_string ();
let mut nickname = String::new ();
while let Some (arg) = args.next () {
match arg.as_str () {
"--bind-addr" => {
bind_addr = match args.next () {
None => return Err (CliArgError::MissingArgumentValue (arg).into ()),
Some (x) => x
};
},
"--nickname" => {
nickname = match args.next () {
None => return Err (CliArgError::MissingArgumentValue (arg).into ()),
Some (x) => x
};
},
_ => return Err (CliArgError::UnrecognizedArgument (arg).into ()),
}
}
let our_mac = get_mac_address ()?.map (|x| x.bytes ());
if our_mac.is_none () {
println! ("Warning: Can't find our own MAC address. We won't be able to respond to MAC-specific lookaround requests");
}
let socket = UdpSocket::bind (SocketAddrV4::new (Ipv4Addr::from_str (&bind_addr)?, common_params.server_port)).await?;
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socket.join_multicast_v4 (common_params.multicast_addr, [0u8, 0, 0, 0].into ())?;
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let mut recent_idem_ids = Vec::with_capacity (32);
loop {
println! ("Waiting for messages...");
let (req_msgs, remote_addr) = match recv_msg_from (&socket).await {
Ok (x) => x,
Err (e) => {
println! ("Error while receiving message: {:?}", e);
continue;
},
};
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let req = match req_msgs.into_iter ().next () {
Some (x) => x,
_ => {
println! ("Don't know how to handle this message, ignoring");
continue;
},
};
let resp = match req {
Message::Request1 {
mac: None,
idem_id,
} => {
if recent_idem_ids.contains (&idem_id) {
println! ("Ignoring request we already processed");
None
}
else {
recent_idem_ids.insert (0, idem_id);
recent_idem_ids.truncate (30);
Some (vec! [
Message::Response1 (our_mac),
Message::Response2 (message::Response2 {
idem_id,
nickname: nickname.clone (),
}),
])
}
},
_ => continue,
};
if let Some (resp) = resp {
socket.send_to (&Message::many_to_vec (&resp)?, remote_addr).await?;
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}
}
}