tui: implement scroll-back for pseudo term

README.md

@@ -219,6 +219,8 @@ Options:
           Set the frame rate of the TUI (60 by default)
   -m, --max-events <MAX_EVENTS>
           Max number of events to keep in TUI (0=unlimited)
+      --scrollback-lines <SCROLLBACK_LINES>
+          Number of scrollback lines to keep in the pseudo terminal (1000 by default)
   -D, --default-external-command <DEFAULT_EXTERNAL_COMMAND>
           Set the default external command to run when using "Detach, Stop and Run Command" feature in Hit Manager
   -b, --add-breakpoint <BREAKPOINTS>

config.toml

@@ -72,6 +72,9 @@
 # Max number of events to keep in TUI. (0=unlimited)
 # max_events = 1_000_000
 
+# Number of scrollback lines to keep in the pseudo terminal
+# scrollback_lines = 1000
+
 #
 # Config for Log mode
 #

crates/tracexec-core/src/cli/args.rs

@@ -490,6 +490,12 @@ pub struct TuiModeArgs {
     help = "Max number of events to keep in TUI (0=unlimited)"
   )]
   pub max_events: Option<u64>,
+  #[clap(
+    long,
+    help = "Number of scrollback lines to keep in the pseudo terminal (1000 by default)",
+    requires = "tty"
+  )]
+  pub scrollback_lines: Option<usize>,
 }
 
 #[derive(Args, Debug, Default, Clone)]
@@ -515,6 +521,7 @@ impl TuiModeArgs {
     self.layout = self.layout.or(config.layout);
     self.frame_rate = self.frame_rate.or(config.frame_rate);
     self.max_events = self.max_events.or(config.max_events);
+    self.scrollback_lines = self.scrollback_lines.or(config.scrollback_lines);
     self.follow |= config.follow.unwrap_or_default();
     if (!self.terminate_on_exit) && (!self.kill_on_exit) {
       match config.exit_handling {

crates/tracexec-core/src/cli/config.rs

@@ -96,6 +96,7 @@ pub struct TuiModeConfig {
   #[serde(default, deserialize_with = "deserialize_frame_rate")]
   pub frame_rate: Option<f64>,
   pub max_events: Option<u64>,
+  pub scrollback_lines: Option<usize>,
 }
 
 #[derive(Debug, Default, Clone, Deserialize, Serialize)]

crates/tracexec-tui/Cargo.toml

@@ -55,3 +55,4 @@ indexset = "0.15"
 [dev-dependencies]
 insta = "1.41.0"
 serial_test = { workspace = true }
+tracing-test = { workspace = true }

crates/tracexec-tui/src/app.rs

@@ -167,6 +167,7 @@ impl App {
             pixel_height: 0,
           },
           pty_master,
+          tui_args.scrollback_lines.unwrap_or(1000),
         )?;
         if active_pane == ActivePane::Terminal {
           term.focus(true);

crates/tracexec-tui/src/app/ui.rs

@@ -235,6 +235,22 @@ impl App {
       items.extend(help_item!("Q", "Quit"));
     } else {
       // Terminal
+      if let Some(term) = self.term.as_ref() {
+        if term.is_scrollback_mode() {
+          // In scrollback mode - show navigation keys highlighted
+          items.extend([
+            help_key("Ctrl+U"),
+            fancy_help_desc("Exit\u{00a0}Scroll"),
+            "\u{200b}".into(),
+          ]);
+          items.extend(help_item!("↑↓", "Scroll"));
+          items.extend(help_item!("PgUp/PgDn", "Page"));
+          items.extend(help_item!("Home/End", "Jump"));
+        } else {
+          // Normal mode - show how to enter scrollback
+          items.extend(help_item!("Ctrl+U", "Scroll"));
+        }
+      }
       if let Some(h) = self.hit_manager_state.as_ref()
         && h.count() > 0
       {