refactor client to prepare for reconnecting

src/server/client.rs

@@ -5,7 +5,7 @@ use crate::mux::domain::alloc_domain_id;
 use crate::mux::domain::DomainId;
 use crate::mux::Mux;
 use crate::server::codec::*;
-use crate::server::domain::ClientDomain;
+use crate::server::domain::{ClientDomain, ClientDomainConfig};
 use crate::server::pollable::*;
 use crate::server::tab::ClientTab;
 use crate::server::UnixStream;
@@ -104,7 +104,7 @@ fn process_unilateral(local_domain_id: DomainId, decoded: DecodedPdu) -> Fallibl
 }
 
 fn client_thread(
-    mut stream: Box<dyn ReadAndWrite>,
+    mut reconnectable: Reconnectable,
     local_domain_id: DomainId,
     rx: PollableReceiver<ReaderMessage>,
 ) -> Fallible<()> {
@@ -120,8 +120,8 @@ fn client_thread(
                         next_serial += 1;
                         promises.insert(serial, promise);
 
-                        pdu.encode(&mut stream, serial)?;
-                        stream.flush()?;
+                        pdu.encode(reconnectable.stream(), serial)?;
+                        reconnectable.stream().flush()?;
                     }
                 },
                 Err(TryRecvError::Empty) => break,
@@ -129,10 +129,10 @@ fn client_thread(
             };
         }
 
-        let mut poll_array = [rx.as_poll_fd(), stream.as_poll_fd()];
+        let mut poll_array = [rx.as_poll_fd(), reconnectable.stream().as_poll_fd()];
         poll_for_read(&mut poll_array);
 
-        if poll_array[1].revents != 0 || stream.has_read_buffered() {
+        if poll_array[1].revents != 0 || reconnectable.stream().has_read_buffered() {
             // When TLS is enabled on a stream, it may require a mixture of
             // reads AND writes in order to satisfy a given read or write.
             // As a result, we may appear ready to read a PDU, but may not
@@ -140,9 +140,9 @@ fn client_thread(
             // Set to non-blocking mode while we try to decode a packet to
             // avoid blocking.
             loop {
-                stream.set_non_blocking(true)?;
-                let res = Pdu::try_read_and_decode(&mut stream, &mut read_buffer);
-                stream.set_non_blocking(false)?;
+                reconnectable.stream().set_non_blocking(true)?;
+                let res = Pdu::try_read_and_decode(reconnectable.stream(), &mut read_buffer);
+                reconnectable.stream().set_non_blocking(false)?;
                 if let Some(decoded) = res? {
                     log::trace!("decoded serial {}", decoded.serial);
                     if decoded.serial == 0 {
@@ -179,56 +179,28 @@ fn unix_connect_with_retry(path: &Path) -> Result<UnixStream, std::io::Error> {
     Err(error)
 }
 
-impl Client {
-    pub fn new(local_domain_id: DomainId, stream: Box<dyn ReadAndWrite>) -> Self {
-        let (sender, receiver) = pollable_channel().expect("failed to create pollable_channel");
+struct Reconnectable {
+    config: ClientDomainConfig,
+    stream: Option<Box<dyn ReadAndWrite>>,
+}
 
-        thread::spawn(move || {
-            if let Err(e) = client_thread(stream, local_domain_id, receiver) {
-                log::debug!("client thread ended: {}", e);
-                Future::with_executor(gui_executor().unwrap(), move || {
-                    let mux = Mux::get().unwrap();
-                    let client_domain = mux
-                        .get_domain(local_domain_id)
-                        .ok_or_else(|| format_err!("no such domain {}", local_domain_id))?;
-                    let client_domain =
-                        client_domain
-                            .downcast_ref::<ClientDomain>()
-                            .ok_or_else(|| {
-                                format_err!(
-                                    "domain {} is not a ClientDomain instance",
-                                    local_domain_id
-                                )
-                            })?;
-                    client_domain.perform_detach();
-                    Ok(())
-                });
+impl Reconnectable {
+    fn new(config: ClientDomainConfig, stream: Option<Box<dyn ReadAndWrite>>) -> Self {
+        Self { config, stream }
     }
-        });
 
-        Self {
-            sender,
-            local_domain_id,
+    fn stream(&mut self) -> &mut Box<dyn ReadAndWrite> {
+        self.stream.as_mut().unwrap()
+    }
+
+    fn connect(&mut self) -> Fallible<()> {
+        match self.config.clone() {
+            ClientDomainConfig::Unix(unix_dom) => self.unix_connect(unix_dom),
+            ClientDomainConfig::Tls(tls) => self.tls_connect(tls),
         }
     }
 
-    pub fn local_domain_id(&self) -> DomainId {
-        self.local_domain_id
-    }
-
-    pub fn new_default_unix_domain(config: &Arc<Config>) -> Fallible<Self> {
-        let unix_dom = config
-            .unix_domains
-            .first()
-            .ok_or_else(|| err_msg("no default unix domain is configured"))?;
-        Self::new_unix_domain(alloc_domain_id(), config, unix_dom)
-    }
-
-    pub fn new_unix_domain(
-        local_domain_id: DomainId,
-        _config: &Arc<Config>,
-        unix_dom: &UnixDomain,
-    ) -> Fallible<Self> {
+    fn unix_connect(&mut self, unix_dom: UnixDomain) -> Fallible<()> {
         let sock_path = unix_dom.socket_path();
         info!("connect to {}", sock_path.display());
 
@@ -252,15 +224,12 @@ impl Client {
         };
 
         let stream: Box<dyn ReadAndWrite> = Box::new(stream);
-        Ok(Self::new(local_domain_id, stream))
+        self.stream.replace(stream);
+        Ok(())
     }
 
     #[cfg(any(feature = "openssl", unix))]
-    pub fn new_tls(
-        local_domain_id: DomainId,
-        _config: &Arc<Config>,
-        tls_client: &TlsDomainClient,
-    ) -> Fallible<Self> {
+    pub fn tls_connect(&mut self, tls_client: TlsDomainClient) -> Fallible<()> {
         use crate::server::listener::read_bytes;
         use openssl::ssl::{SslConnector, SslFiletype, SslMethod};
         use openssl::x509::X509;
@@ -333,15 +302,12 @@ impl Client {
                     )
                 })?,
         );
-        Ok(Self::new(local_domain_id, stream))
+        self.stream.replace(stream);
+        Ok(())
     }
 
     #[cfg(not(any(feature = "openssl", unix)))]
-    pub fn new_tls(
-        local_domain_id: DomainId,
-        _config: &Arc<Config>,
-        tls_client: &TlsDomainClient,
-    ) -> Fallible<Self> {
+    pub fn tls_connect(&mut self, tls_client: TlsDomainClient) -> Fallible<()> {
         use crate::server::listener::IdentitySource;
         use native_tls::TlsConnector;
         use std::convert::TryInto;
@@ -383,7 +349,76 @@ impl Client {
                 e
             )
         })?);
-        Ok(Self::new(local_domain_id, stream))
+        self.stream.replace(stream);
+        Ok(())
+    }
+}
+
+impl Client {
+    fn new(local_domain_id: DomainId, reconnectable: Reconnectable) -> Self {
+        let (sender, receiver) = pollable_channel().expect("failed to create pollable_channel");
+
+        thread::spawn(move || {
+            if let Err(e) = client_thread(reconnectable, local_domain_id, receiver) {
+                log::debug!("client thread ended: {}", e);
+                Future::with_executor(gui_executor().unwrap(), move || {
+                    let mux = Mux::get().unwrap();
+                    let client_domain = mux
+                        .get_domain(local_domain_id)
+                        .ok_or_else(|| format_err!("no such domain {}", local_domain_id))?;
+                    let client_domain =
+                        client_domain
+                            .downcast_ref::<ClientDomain>()
+                            .ok_or_else(|| {
+                                format_err!(
+                                    "domain {} is not a ClientDomain instance",
+                                    local_domain_id
+                                )
+                            })?;
+                    client_domain.perform_detach();
+                    Ok(())
+                });
+            }
+        });
+
+        Self {
+            sender,
+            local_domain_id,
+        }
+    }
+
+    pub fn local_domain_id(&self) -> DomainId {
+        self.local_domain_id
+    }
+
+    pub fn new_default_unix_domain(config: &Arc<Config>) -> Fallible<Self> {
+        let unix_dom = config
+            .unix_domains
+            .first()
+            .ok_or_else(|| err_msg("no default unix domain is configured"))?;
+        Self::new_unix_domain(alloc_domain_id(), config, unix_dom)
+    }
+
+    pub fn new_unix_domain(
+        local_domain_id: DomainId,
+        _config: &Arc<Config>,
+        unix_dom: &UnixDomain,
+    ) -> Fallible<Self> {
+        let mut reconnectable =
+            Reconnectable::new(ClientDomainConfig::Unix(unix_dom.clone()), None);
+        reconnectable.connect()?;
+        Ok(Self::new(local_domain_id, reconnectable))
+    }
+
+    pub fn new_tls(
+        local_domain_id: DomainId,
+        _config: &Arc<Config>,
+        tls_client: &TlsDomainClient,
+    ) -> Fallible<Self> {
+        let mut reconnectable =
+            Reconnectable::new(ClientDomainConfig::Tls(tls_client.clone()), None);
+        reconnectable.connect()?;
+        Ok(Self::new(local_domain_id, reconnectable))
     }
 
     pub fn send_pdu(&self, pdu: Pdu) -> Future<Pdu> {

src/server/domain.rs

@@ -54,6 +54,7 @@ impl ClientInner {
     }
 }
 
+#[derive(Clone, Debug)]
 pub enum ClientDomainConfig {
     Unix(UnixDomain),
     Tls(TlsDomainClient),