discovery: allow setting port explicitly

src/authentication/discovery.rs

@@ -13,6 +13,7 @@ use rand;
 use std::collections::BTreeMap;
 use std::io;
 use std::sync::Arc;
+use std::net::{SocketAddr,IpAddr,Ipv4Addr};
 use tokio_core::net::TcpListener;
 use tokio_core::reactor::Handle;
 use url;
@@ -206,12 +207,13 @@ pub struct DiscoveryStream {
     task: Box<Future<Item=(), Error=io::Error>>,
 }
 
-pub fn discovery(handle: &Handle, device_name: String, device_id: String)
+pub fn discovery(handle: &Handle, device_name: String, device_id: String, discovery_port: Option<u16>)
     -> io::Result<DiscoveryStream>
 {
     let (discovery, creds_rx) = Discovery::new(device_name.clone(), device_id);
+    let bind_addr = SocketAddr::new(IpAddr::V4(Ipv4Addr::new(0, 0, 0, 0)), discovery_port.unwrap_or(0));
 
-    let listener = TcpListener::bind(&"0.0.0.0:0".parse().unwrap(), handle)?;
+    let listener = TcpListener::bind(&bind_addr, handle)?;
     let addr = listener.local_addr()?;
 
     let http = Http::new();

src/main.rs

@@ -93,6 +93,7 @@ fn setup(args: &[String]) -> Setup {
         .optflag("v", "verbose", "Enable verbose output")
         .optopt("u", "username", "Username to sign in with", "USERNAME")
         .optopt("p", "password", "Password", "PASSWORD")
+        .optopt("", "discovery-port", "Explicitly set TCP port used for discovery", "PORT")
         .optflag("", "disable-discovery", "Disable discovery mode")
         .optopt("", "backend", "Audio backend to use. Use '?' to list options", "BACKEND")
         .optopt("", "device", "Audio device to use. Use '?' to list options", "DEVICE")
@@ -145,13 +146,15 @@ fn setup(args: &[String]) -> Setup {
                                       cached_credentials);
 
     let enable_discovery = !matches.opt_present("disable-discovery");
+    let discovery_port = matches.opt_str("discovery-port").map(|x| x.parse::<u16>().expect("invalid port"));
 
     let config = Config {
         user_agent: version::version_string(),
         device_id: device_id,
         bitrate: bitrate,
         onstart: matches.opt_str("onstart"),
         onstop: matches.opt_str("onstop"),
+        discovery_port: discovery_port
     };
 
     let device = matches.opt_str("device");
@@ -217,8 +220,9 @@ impl Main {
     fn discovery(&mut self) {
         let device_id = self.config.device_id.clone();
         let name = self.name.clone();
+        let discovery_port = self.config.discovery_port;
 
-        self.discovery = Some(discovery(&self.handle, name, device_id).unwrap());
+        self.discovery = Some(discovery(&self.handle, name, device_id, discovery_port).unwrap());
     }
 
     fn credentials(&mut self, credentials: Credentials) {

src/session.rs

@@ -49,6 +49,7 @@ pub struct Config {
     pub bitrate: Bitrate,
     pub onstart: Option<String>,
     pub onstop: Option<String>,
+    pub discovery_port: Option<u16>
 }
 
 impl Default for Config {
@@ -60,6 +61,7 @@ impl Default for Config {
             bitrate: Bitrate::Bitrate160,
             onstart: None,
             onstop: None,
+            discovery_port: None,
         }
     }
 }