fix(input): handle discontiguous STDIN input (#1119)

* log stdin reads and events

* attempt fix for incomplete mouse sequences

* read events directly from stdin

* fix flaky e2e test

* bring back bracketed paste

* rustfmt

* remove unused

Co-authored-by: Thomas Linford <linford.t@gmail.com>

src/tests/e2e/cases.rs

@@ -1733,7 +1733,7 @@ pub fn focus_tab_with_layout() {
                 let mut step_is_complete = false;
                 if remote_terminal.status_bar_appears()
                     && remote_terminal.tip_appears()
-                    && remote_terminal.snapshot_contains("Tab #3")
+                    && remote_terminal.snapshot_contains("Tab #9")
                     && remote_terminal.cursor_position_is(63, 2)
                 {
                     step_is_complete = true;

zellij-client/src/input_handler.rs

@@ -95,29 +95,9 @@ impl InputHandler {
                         }
                     }
                 }
-                Ok((
-                    InputInstruction::PastedText((
-                        send_bracketed_paste_start,
-                        raw_bytes,
-                        send_bracketed_paste_end,
-                    )),
-                    _error_context,
-                )) => {
+                Ok((InputInstruction::PastedText(raw_bytes), _error_context)) => {
                     if self.mode == InputMode::Normal || self.mode == InputMode::Locked {
-                        if send_bracketed_paste_start {
-                            let bracketed_paste_start = vec![27, 91, 50, 48, 48, 126]; // \u{1b}[200~
-                            let paste_start_action = Action::Write(bracketed_paste_start);
-                            self.dispatch_action(paste_start_action);
-                        }
-
-                        let pasted_text_action = Action::Write(raw_bytes);
-                        self.dispatch_action(pasted_text_action);
-
-                        if send_bracketed_paste_end {
-                            let bracketed_paste_end = vec![27, 91, 50, 48, 49, 126]; // \u{1b}[201~
-                            let paste_end_action = Action::Write(bracketed_paste_end);
-                            self.dispatch_action(paste_end_action);
-                        }
+                        self.dispatch_action(Action::Write(raw_bytes));
                     }
                 }
                 Ok((InputInstruction::SwitchToMode(input_mode), _error_context)) => {

zellij-client/src/lib.rs

@@ -107,7 +107,7 @@ impl ClientInfo {
 pub(crate) enum InputInstruction {
     KeyEvent(termion::event::Event, Vec<u8>),
     SwitchToMode(InputMode),
-    PastedText((bool, Vec<u8>, bool)), // (send_brackted_paste_start, pasted_text, send_bracketed_paste_end)
+    PastedText(Vec<u8>),
 }
 
 pub fn start_client(

zellij-client/src/os_input_output.rs

@@ -82,6 +82,7 @@ pub trait ClientOsApi: Send + Sync {
     fn unset_raw_mode(&self, fd: RawFd);
     /// Returns the writer that allows writing to standard output.
     fn get_stdout_writer(&self) -> Box<dyn io::Write>;
+    fn get_stdin_reader(&self) -> Box<dyn io::Read>;
     /// Returns the raw contents of standard input.
     fn read_from_stdin(&self) -> Vec<u8>;
     /// Returns a [`Box`] pointer to this [`ClientOsApi`] struct.
@@ -128,6 +129,11 @@ impl ClientOsApi for ClientOsInputOutput {
         let stdout = ::std::io::stdout();
         Box::new(stdout)
     }
+    fn get_stdin_reader(&self) -> Box<dyn io::Read> {
+        let stdin = ::std::io::stdin();
+        Box::new(stdin)
+    }
+
     fn send_to_server(&self, msg: ClientToServerMsg) {
         self.send_instructions_to_server
             .lock()

zellij-client/src/stdin_handler.rs

@@ -29,143 +29,81 @@ fn keys_to_adjust() -> HashMap<Vec<u8>, Vec<u8>> {
     keys_to_adjust
 }
 
-fn bracketed_paste_end_position(stdin_buffer: &[u8]) -> Option<usize> {
-    let bracketed_paste_end = vec![27, 91, 50, 48, 49, 126]; // \u{1b}[201~
-    let mut bp_position = 0;
-    let mut position = None;
-    for (i, byte) in stdin_buffer.iter().enumerate() {
-        if Some(byte) == bracketed_paste_end.get(bp_position) {
-            position = Some(i);
-            bp_position += 1;
-            if bp_position == bracketed_paste_end.len() {
-                break;
-            }
-        } else {
-            bp_position = 0;
-            position = None;
-        }
-    }
-    if bp_position == bracketed_paste_end.len() {
-        position
-    } else {
-        None
-    }
-}
-
 pub(crate) fn stdin_loop(
     os_input: Box<dyn ClientOsApi>,
     send_input_instructions: SenderWithContext<InputInstruction>,
 ) {
     let mut pasting = false;
-    let bracketed_paste_start = vec![27, 91, 50, 48, 48, 126]; // \u{1b}[200~
+    let mut pasted_text = vec![];
+    let bracketed_paste_start = termion::event::Event::Unsupported(vec![27, 91, 50, 48, 48, 126]); // \u{1b}[200~
+    let bracketed_paste_end = termion::event::Event::Unsupported(vec![27, 91, 50, 48, 49, 126]); // \u{1b}[201~
     let csi_mouse_sgr_start = vec![27, 91, 60];
     let adjusted_keys = keys_to_adjust();
-    loop {
-        let mut stdin_buffer = os_input.read_from_stdin();
-        if pasting
-            || (stdin_buffer.len() > bracketed_paste_start.len()
-                && stdin_buffer
-                    .iter()
-                    .take(bracketed_paste_start.len())
-                    .eq(&bracketed_paste_start))
-        {
-            match bracketed_paste_end_position(&stdin_buffer) {
-                Some(paste_end_position) => {
-                    let starts_with_bracketed_paste_start = stdin_buffer
-                        .iter()
-                        .take(bracketed_paste_start.len())
-                        .eq(&bracketed_paste_start);
+    for key_result in os_input.get_stdin_reader().events_and_raw() {
+        let (key_event, mut raw_bytes) = key_result.unwrap();
 
-                    let ends_with_bracketed_paste_end = true;
-
-                    let mut pasted_input: Vec<u8> =
-                        stdin_buffer.drain(..=paste_end_position).collect();
-                    if starts_with_bracketed_paste_start {
-                        drop(pasted_input.drain(..6)); // bracketed paste start
-                    }
-                    drop(pasted_input.drain(pasted_input.len() - 6..)); // bracketed paste end
-
-                    send_input_instructions
-                        .send(InputInstruction::PastedText((
-                            starts_with_bracketed_paste_start,
-                            pasted_input,
-                            ends_with_bracketed_paste_end,
-                        )))
-                        .unwrap();
-                    pasting = false;
-                }
-                None => {
-                    let starts_with_bracketed_paste_start = stdin_buffer
-                        .iter()
-                        .take(bracketed_paste_start.len())
-                        .eq(&bracketed_paste_start);
-                    if starts_with_bracketed_paste_start {
-                        drop(stdin_buffer.drain(..6)); // bracketed paste start
-                    }
-
-                    send_input_instructions
-                        .send(InputInstruction::PastedText((
-                            starts_with_bracketed_paste_start,
-                            stdin_buffer,
-                            false,
-                        )))
-                        .unwrap();
-                    pasting = true;
-                    continue;
-                }
-            }
-        }
-        if stdin_buffer.is_empty() {
+        if key_event == bracketed_paste_start {
+            pasting = true;
+            pasted_text.append(&mut raw_bytes);
+            continue;
+        } else if pasting && key_event == bracketed_paste_end {
+            pasting = false;
+            let mut pasted_text: Vec<u8> = pasted_text.drain(..).collect();
+            pasted_text.append(&mut raw_bytes);
+            send_input_instructions
+                .send(InputInstruction::PastedText(pasted_text))
+                .unwrap();
+            continue;
+        } else if pasting {
+            pasted_text.append(&mut raw_bytes);
             continue;
         }
-        for key_result in stdin_buffer.events_and_raw() {
-            let (key_event, raw_bytes) = key_result.unwrap();
-            let raw_bytes = adjusted_keys.get(&raw_bytes).cloned().unwrap_or(raw_bytes);
-            if let termion::event::Event::Mouse(me) = key_event {
-                let mouse_event = zellij_utils::input::mouse::MouseEvent::from(me);
-                if let MouseEvent::Hold(_) = mouse_event {
-                    // as long as the user is holding the mouse down (no other stdin, eg.
-                    // MouseRelease) we need to keep sending this instruction to the app,
-                    // because the app itself doesn't have an event loop in the proper
-                    // place
-                    let mut poller = os_input.stdin_poller();
+
+        let raw_bytes = adjusted_keys.get(&raw_bytes).cloned().unwrap_or(raw_bytes);
+        if let termion::event::Event::Mouse(me) = key_event {
+            let mouse_event = zellij_utils::input::mouse::MouseEvent::from(me);
+            if let MouseEvent::Hold(_) = mouse_event {
+                // as long as the user is holding the mouse down (no other stdin, eg.
+                // MouseRelease) we need to keep sending this instruction to the app,
+                // because the app itself doesn't have an event loop in the proper
+                // place
+                let mut poller = os_input.stdin_poller();
+                send_input_instructions
+                    .send(InputInstruction::KeyEvent(
+                        key_event.clone(),
+                        raw_bytes.clone(),
+                    ))
+                    .unwrap();
+                loop {
+                    let ready = poller.ready();
+                    if ready {
+                        break;
+                    }
                     send_input_instructions
                         .send(InputInstruction::KeyEvent(
                             key_event.clone(),
                             raw_bytes.clone(),
                         ))
                         .unwrap();
-                    loop {
-                        let ready = poller.ready();
-                        if ready {
-                            break;
-                        }
-                        send_input_instructions
-                            .send(InputInstruction::KeyEvent(
-                                key_event.clone(),
-                                raw_bytes.clone(),
-                            ))
-                            .unwrap();
-                    }
-                    continue;
                 }
+                continue;
             }
-
-            // FIXME: termion does not properly parse some csi sgr mouse sequences
-            // like ctrl + click.
-            // As a workaround, to avoid writing these sequences to tty stdin,
-            // we discard them.
-            if let termion::event::Event::Unsupported(_) = key_event {
-                if raw_bytes.len() > csi_mouse_sgr_start.len()
-                    && raw_bytes[0..csi_mouse_sgr_start.len()] == csi_mouse_sgr_start
-                {
-                    continue;
-                }
-            }
-
-            send_input_instructions
-                .send(InputInstruction::KeyEvent(key_event, raw_bytes))
-                .unwrap();
         }
+
+        // FIXME: termion does not properly parse some csi sgr mouse sequences
+        // like ctrl + click.
+        // As a workaround, to avoid writing these sequences to tty stdin,
+        // we discard them.
+        if let termion::event::Event::Unsupported(_) = key_event {
+            if raw_bytes.len() > csi_mouse_sgr_start.len()
+                && raw_bytes[0..csi_mouse_sgr_start.len()] == csi_mouse_sgr_start
+            {
+                continue;
+            }
+        }
+
+        send_input_instructions
+            .send(InputInstruction::KeyEvent(key_event, raw_bytes))
+            .unwrap();
     }
 }

zellij-client/src/unit/input_handler_tests.rs

@@ -106,6 +106,9 @@ impl ClientOsApi for FakeClientOsApi {
     fn get_stdout_writer(&self) -> Box<dyn io::Write> {
         unimplemented!()
     }
+    fn get_stdin_reader(&self) -> Box<dyn io::Read> {
+        unimplemented!()
+    }
     fn read_from_stdin(&self) -> Vec<u8> {
         unimplemented!()
     }