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@jfager
Last active December 18, 2015 09:59
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Writing a websocket server in Rust, ran into an issue where the server would hang after a few connection attempts. Here's a minimal client/server; in the server, if you uncomment the separate spawned task on the default scheduler, the hang always happens. Putting that other task on its own thread makes everything work fine.
extern mod extra;
use std::{int,io,result};
use extra::{net,net_tcp,uv};
fn main() {
let (accept_port, accept_chan) = stream();
let (finish_port, finish_chan) = stream();
let addr = extra::net_ip::v4::parse_addr("127.0.0.1");
let port = 8080;
do spawn {
let backlog = 128;
let iotask = &uv::global_loop::get();
net::tcp::listen(addr, port, backlog, iotask,
|_| {
io::println("Init callback");
},
|conn, kill_ch| {
io::println("Listen callback");
let (res_po, res_ch) = stream::<Option<net_tcp::TcpErrData>>();
accept_chan.send((conn, res_ch));
match res_po.recv() {
Some(err_data) => kill_ch.send(Some(err_data)),
None => ()
}
});
io::println("Done listening");
finish_chan.send(());
}
do spawn {
loop {
io::println("Waiting on accept_port");
let (conn, res_ch) = accept_port.recv();
io::println("accept_port received, spawning for accept");
do std::task::spawn {
io::println("Spawned");
let accept_result = net::tcp::accept(conn);
io::println("Accepted");
match accept_result {
Err(accept_error) => {
res_ch.send(Some(accept_error));
// fail?
},
Ok(sock) => {
res_ch.send(None);
let buf = net::tcp::socket_buf(sock);
let line = buf.read_line();
io::println(fmt!("From client: %s", line));
buf.write_str("pong\n");
}
}
io::println("Accept task completed");
}
}
}
// Oops, spawning in the default scheduler.
//do spawn {
// loop {
// unsafe { std::libc::sleep(1); }
// }
//}
// Put this task in its own thread and everything works great.
do task::spawn_sched(task::ManualThreads(1)) {
loop {
io::println("herp");
unsafe { std::libc::sleep(1); }
}
}
finish_port.recv();
}
extern mod extra;
use std::{int,io,result};
use extra::{net,net_tcp,uv};
fn main() {
let addr = extra::net_ip::v4::parse_addr("127.0.0.1");
let port = 8080;
let mut counter = 0;
loop {
let iotask = &uv::global_loop::get();
let connect_result = net_tcp::connect(copy addr, port, iotask);
assert!(connect_result.is_ok());
let sock = result::unwrap(connect_result);
let buf = net_tcp::socket_buf(sock);
buf.write_str(fmt!("ping %i\n", counter));
let line = buf.read_line();
io::println(fmt!("From server: %s", line));
counter += 1;
unsafe { std::libc::sleep(1); }
}
}
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