improve localnet-sanity's robustness (#1160)

* fix poll_gossip_for_leader() loop to actually wait
         for 30 seconds
    * reduce reuseaddr use to only when necessary,
         try to avoid already bound sockets
    * move nat.rs to netutil.rs
    * add gossip tracing to thin_client and bench-tps

src/netutil.rs

@@ -0,0 +1,173 @@
+//! The `netutil` module assists with networking
+
+use nix::sys::socket::setsockopt;
+use nix::sys::socket::sockopt::{ReuseAddr, ReusePort};
+use pnet_datalink as datalink;
+use rand::{thread_rng, Rng};
+use reqwest;
+use socket2::{Domain, SockAddr, Socket, Type};
+use std::io;
+use std::net::{IpAddr, Ipv4Addr, SocketAddr, UdpSocket};
+use std::os::unix::io::AsRawFd;
+
+/// A data type representing a public Udp socket
+pub struct UdpSocketPair {
+    pub addr: SocketAddr,    // Public address of the socket
+    pub receiver: UdpSocket, // Locally bound socket that can receive from the public address
+    pub sender: UdpSocket,   // Locally bound socket to send via public address
+}
+
+/// Tries to determine the public IP address of this machine
+pub fn get_public_ip_addr() -> Result<IpAddr, String> {
+    let body = reqwest::get("http://ifconfig.co/ip")
+        .map_err(|err| err.to_string())?
+        .text()
+        .map_err(|err| err.to_string())?;
+
+    match body.lines().next() {
+        Some(ip) => Result::Ok(ip.parse().unwrap()),
+        None => Result::Err("Empty response body".to_string()),
+    }
+}
+
+pub fn parse_port_or_addr(optstr: Option<&str>, default_port: u16) -> SocketAddr {
+    let daddr = SocketAddr::from(([0, 0, 0, 0], default_port));
+
+    if let Some(addrstr) = optstr {
+        if let Ok(port) = addrstr.parse() {
+            let mut addr = daddr;
+            addr.set_port(port);
+            addr
+        } else if let Ok(addr) = addrstr.parse() {
+            addr
+        } else {
+            daddr
+        }
+    } else {
+        daddr
+    }
+}
+
+pub fn get_ip_addr() -> Option<IpAddr> {
+    for iface in datalink::interfaces() {
+        for p in iface.ips {
+            if !p.ip().is_loopback() && !p.ip().is_multicast() {
+                match p.ip() {
+                    IpAddr::V4(addr) => {
+                        if !addr.is_link_local() {
+                            return Some(p.ip());
+                        }
+                    }
+                    IpAddr::V6(_addr) => {
+                        // Select an ipv6 address if the config is selected
+                        #[cfg(feature = "ipv6")]
+                        {
+                            return Some(p.ip());
+                        }
+                    }
+                }
+            }
+        }
+    }
+    None
+}
+
+fn udp_socket(reuseaddr: bool) -> io::Result<Socket> {
+    let sock = Socket::new(Domain::ipv4(), Type::dgram(), None)?;
+    let sock_fd = sock.as_raw_fd();
+
+    if reuseaddr {
+        // best effort, i.e. ignore errors here, we'll get the failure in caller
+        setsockopt(sock_fd, ReusePort, &true).ok();
+        setsockopt(sock_fd, ReuseAddr, &true).ok();
+    }
+
+    Ok(sock)
+}
+
+pub fn bind_in_range(range: (u16, u16)) -> io::Result<(u16, UdpSocket)> {
+    let sock = udp_socket(false)?;
+
+    let (start, end) = range;
+    let mut tries_left = end - start;
+    loop {
+        let rand_port = thread_rng().gen_range(start, end);
+        let addr = SocketAddr::new(IpAddr::V4(Ipv4Addr::new(0, 0, 0, 0)), rand_port);
+
+        match sock.bind(&SockAddr::from(addr)) {
+            Ok(_) => {
+                let sock = sock.into_udp_socket();
+                break Result::Ok((sock.local_addr().unwrap().port(), sock));
+            }
+            Err(err) => if err.kind() != io::ErrorKind::AddrInUse || tries_left == 0 {
+                return Err(err);
+            },
+        }
+        tries_left -= 1;
+    }
+}
+
+// binds many sockets to the same port in a range
+pub fn multi_bind_in_range(range: (u16, u16), num: usize) -> io::Result<(u16, Vec<UdpSocket>)> {
+    let mut sockets = Vec::with_capacity(num);
+
+    let port = {
+        let (port, _) = bind_in_range(range)?;
+        port
+    }; // drop the probe, port should be available... briefly.
+
+    for _ in 0..num {
+        sockets.push(bind_to(port, true)?);
+    }
+    Ok((port, sockets))
+}
+
+pub fn bind_to(port: u16, reuseaddr: bool) -> io::Result<UdpSocket> {
+    let sock = udp_socket(reuseaddr)?;
+
+    let addr = SocketAddr::new(IpAddr::V4(Ipv4Addr::new(0, 0, 0, 0)), port);
+
+    match sock.bind(&SockAddr::from(addr)) {
+        Ok(_) => Result::Ok(sock.into_udp_socket()),
+        Err(err) => Err(err),
+    }
+}
+
+#[cfg(test)]
+mod tests {
+    use netutil::*;
+
+    #[test]
+    fn test_parse_port_or_addr() {
+        let p1 = parse_port_or_addr(Some("9000"), 1);
+        assert_eq!(p1.port(), 9000);
+        let p2 = parse_port_or_addr(Some("127.0.0.1:7000"), 1);
+        assert_eq!(p2.port(), 7000);
+        let p2 = parse_port_or_addr(Some("hi there"), 1);
+        assert_eq!(p2.port(), 1);
+        let p3 = parse_port_or_addr(None, 1);
+        assert_eq!(p3.port(), 1);
+    }
+
+    #[test]
+    fn test_bind() {
+        assert_eq!(bind_in_range((2000, 2001)).unwrap().0, 2000);
+        let x = bind_to(2002, true).unwrap();
+        let y = bind_to(2002, true).unwrap();
+        assert_eq!(
+            x.local_addr().unwrap().port(),
+            y.local_addr().unwrap().port()
+        );
+        let (port, v) = multi_bind_in_range((2010, 2110), 10).unwrap();
+        for sock in &v {
+            assert_eq!(port, sock.local_addr().unwrap().port());
+        }
+    }
+
+    #[test]
+    #[should_panic]
+    fn test_bind_in_range_nil() {
+        let _ = bind_in_range((2000, 2000));
+    }
+
+}