top: tui impl n # (max list display)

Author: Bluemangoo

src/uu/top/src/tui/input.rs

@@ -18,6 +18,7 @@ pub(crate) enum InputMode {
 }
 #[derive(Eq, PartialEq, Copy, Clone)]
 pub(crate) enum InputEvent {
+    MaxListDisplay,
     NumaNode,
 }
 
@@ -80,6 +81,17 @@ pub fn handle_input(
                 stat.memory_graph_mode = stat.memory_graph_mode.next();
                 should_update.store(true, Ordering::Relaxed);
             }
+            char!('n') => {
+                let mut stat = tui_stat.write().unwrap();
+                stat.input_label = format!(
+                    "Maximum tasks = {}, change to (0 is unlimited)",
+                    stat.max_list_display
+                );
+                stat.input_value.clear();
+                stat.input_mode = InputMode::Input(InputEvent::MaxListDisplay);
+
+                should_update.store(true, Ordering::Relaxed);
+            }
             char!('R') => {
                 {
                     let mut stat = tui_stat.write().unwrap();
@@ -147,6 +159,17 @@ pub fn handle_input(
                 stat.cpu_column = stat.cpu_column % 8 + 1;
                 should_update.store(true, Ordering::Relaxed);
             }
+            char!('#') => {
+                let mut stat = tui_stat.write().unwrap();
+                stat.input_label = format!(
+                    "Maximum tasks = {}, change to (0 is unlimited)",
+                    stat.max_list_display
+                );
+                stat.input_value.clear();
+                stat.input_mode = InputMode::Input(InputEvent::MaxListDisplay);
+
+                should_update.store(true, Ordering::Relaxed);
+            }
             char!('<') => {
                 {
                     let mut stat = tui_stat.write().unwrap();
@@ -255,6 +278,21 @@ fn handle_input_value(
     should_update: &AtomicBool,
 ) {
     match input_event {
+        InputEvent::MaxListDisplay => {
+            let input_value = { tui_stat.read().unwrap().input_value.parse::<usize>() };
+            if input_value.is_err() {
+                let mut stat = tui_stat.write().unwrap();
+                stat.reset_input();
+                stat.input_error = Some(" invalid number ".into());
+                should_update.store(true, Ordering::Relaxed);
+                return;
+            }
+            let input_value = input_value.unwrap();
+            let mut stat = tui_stat.write().unwrap();
+            stat.max_list_display = input_value;
+            stat.reset_input();
+            should_update.store(true, Ordering::Relaxed);
+        }
         InputEvent::NumaNode => {
             let input_value = { tui_stat.read().unwrap().input_value.parse::<usize>() };
             let numa_nodes = get_numa_nodes();

src/uu/top/src/tui/mod.rs

@@ -497,6 +497,11 @@ impl Widget for Tui<'_> {
 
         self.render_header(layout[0], buf);
         self.render_input(layout[1], buf);
-        self.render_list(layout[2], buf);
+        let mut list_area = layout[2];
+        if self.stat.max_list_display > 0 {
+            let list_height = min(layout[2].height, self.stat.max_list_display as u16) + 1; // 1 for header
+            list_area.height = list_height;
+        }
+        self.render_list(list_area, buf);
     }
 }

src/uu/top/src/tui/stat.rs

@@ -20,6 +20,7 @@ pub(crate) struct TuiStat {
     pub cpu_column: u16,
     pub list_offset: usize,
     pub horizontal_offset: usize,
+    pub max_list_display: usize,
     pub colorful: bool,
     pub full_command_line: bool,
     pub delay: Duration,
@@ -53,6 +54,7 @@ impl TuiStat {
             cpu_column: 2,
             list_offset: 0,
             horizontal_offset: 0,
+            max_list_display: 0, // unlimited
             colorful: true,
             full_command_line: true,
             delay: Duration::from_millis(1500), // 1.5s