imap: interpret empty server response as BYE

This should trigger a reconnect to the IMAP server.

Signed-off-by: Manos Pitsidianakis <manos@pitsidianak.is>

melib/src/imap/connection.rs

@@ -55,7 +55,7 @@ use crate::{
     imap::{
         protocol_parser::{
             self, id_ext::id_ext_response, ImapLineSplit, ImapResponse, RequiredResponses,
-            SelectResponse,
+            ResponseCode, SelectResponse,
         },
         Capabilities, ImapServerConf, UIDStore,
     },
@@ -926,6 +926,12 @@ impl ImapConnection {
             *self.uid_store.is_online.lock().unwrap() = (SystemTime::now(), Ok(()));
 
             match self.server_conf.protocol {
+                ImapProtocol::IMAP { .. } if response.trim().is_empty() => {
+                    let r: ImapResponse =
+                        ImapResponse::Bye(ResponseCode::Alert("Disconnected".into()));
+                    self.stream = Err(Error::new("Offline"));
+                    r.into()
+                }
                 ImapProtocol::IMAP { .. } => {
                     let r: ImapResponse = ImapResponse::try_from(response.as_slice())?;
                     match r {

melib/src/imap/protocol_parser.rs

@@ -302,12 +302,12 @@ pub enum ImapResponse {
 
 impl TryFrom<&'_ [u8]> for ImapResponse {
     type Error = Error;
-    fn try_from(val: &'_ [u8]) -> Result<Self> {
-        let val: &[u8] = val.split_rn().last().unwrap_or(val);
+    fn try_from(original_val: &'_ [u8]) -> Result<Self> {
+        let val: &[u8] = original_val.split_rn().last().unwrap_or(original_val);
         let mut val = val[val.find(b" ").ok_or_else(|| {
             Error::new(format!(
                 "Expected tagged IMAP response (OK,NO,BAD, etc) but found {:?}",
-                val
+                String::from_utf8_lossy(original_val)
             ))
         })? + 1..]
             .trim();
@@ -317,7 +317,7 @@ impl TryFrom<&'_ [u8]> for ImapResponse {
             val = &val[..val.rfind(b"(").ok_or_else(|| {
                 Error::new(format!(
                     "Expected tagged IMAP response (OK,NO,BAD, etc) but found {:?}",
-                    val
+                    String::from_utf8_lossy(original_val)
                 ))
             })?];
         }
@@ -335,7 +335,7 @@ impl TryFrom<&'_ [u8]> for ImapResponse {
         } else {
             return Err(Error::new(format!(
                 "Expected tagged IMAP response (OK,NO,BAD, etc) but found {:?}",
-                val
+                String::from_utf8_lossy(original_val)
             )));
         })
     }