xmlstream: implement simple timeout logic

This allows to detect and handle dying streams without getting stuck
forever.

Timeouts are always wrong, though, so we put the burden of choosing the
right values (mostly) on the creator of a stream.

xmpp/src/builder.rs

@@ -15,6 +15,7 @@ use tokio_xmpp::{
         disco::{DiscoInfoResult, Feature, Identity},
         ns,
     },
+    xmlstream::Timeouts,
     Client as TokioXmppClient,
 };
 
@@ -51,6 +52,7 @@ pub struct ClientBuilder<'a, C: ServerConnector> {
     disco: (ClientType, String),
     features: Vec<ClientFeature>,
     resource: Option<String>,
+    timeouts: Timeouts,
 }
 
 #[cfg(any(feature = "starttls-rust", feature = "starttls-native"))]
@@ -80,6 +82,7 @@ impl<C: ServerConnector> ClientBuilder<'_, C> {
             disco: (ClientType::default(), String::from("tokio-xmpp")),
             features: vec![],
             resource: None,
+            timeouts: Timeouts::default(),
         }
     }
 
@@ -109,6 +112,15 @@ impl<C: ServerConnector> ClientBuilder<'_, C> {
         self
     }
 
+    /// Configure the timeouts used.
+    ///
+    /// See [`Timeouts`] for more information on the semantics and the
+    /// defaults (which are used unless you call this method).
+    pub fn set_timeouts(mut self, timeouts: Timeouts) -> Self {
+        self.timeouts = timeouts;
+        self
+    }
+
     pub fn enable_feature(mut self, feature: ClientFeature) -> Self {
         self.features.push(feature);
         self
@@ -146,8 +158,12 @@ impl<C: ServerConnector> ClientBuilder<'_, C> {
             self.jid.clone().into()
         };
 
-        let mut client =
-            TokioXmppClient::new_with_connector(jid, self.password, self.server_connector.clone());
+        let mut client = TokioXmppClient::new_with_connector(
+            jid,
+            self.password,
+            self.server_connector.clone(),
+            self.timeouts,
+        );
         client.set_reconnect(true);
         self.build_impl(client)
     }