start building out the muxed client Domain

src/server/domain.rs

@@ -0,0 +1,46 @@
+use crate::mux::domain::{alloc_domain_id, Domain, DomainId};
+use crate::mux::tab::Tab;
+use crate::server::client::Client;
+use crate::server::codec::Spawn;
+use failure::{bail, Fallible};
+use portable_pty::{CommandBuilder, PtySize};
+use std::rc::Rc;
+use std::sync::{Arc, Mutex};
+
+pub struct ClientDomain {
+    client: Arc<Mutex<Client>>,
+    local_domain_id: DomainId,
+    remote_domain_id: DomainId,
+}
+
+impl ClientDomain {
+    pub fn new(client: &Arc<Mutex<Client>>) -> Self {
+        let local_domain_id = alloc_domain_id();
+        // Assumption: that the domain id on the other end is
+        // always the first created default domain.  In the future
+        // we'll add a way to discover/enumerate domains to populate
+        // this a bit rigorously.
+        let remote_domain_id = 0;
+        Self {
+            client: Arc::clone(client),
+            local_domain_id,
+            remote_domain_id,
+        }
+    }
+}
+
+impl Domain for ClientDomain {
+    fn domain_id(&self) -> DomainId {
+        self.local_domain_id
+    }
+
+    fn spawn(&self, size: PtySize, command: Option<CommandBuilder>) -> Fallible<Rc<dyn Tab>> {
+        let mut client = self.client.lock().unwrap();
+        let remote_tab_id = client.spawn(Spawn {
+            domain_id: self.remote_domain_id,
+            size,
+            command,
+        });
+        bail!("need to wrap in a tab proxy");
+    }
+}

src/server/mod.rs

@@ -5,4 +5,5 @@ use uds_windows::{UnixListener, UnixStream};
 
 pub mod client;
 pub mod codec;
+pub mod domain;
 pub mod listener;