top: tui impl ^g (show cgroup)

Author: Bluemangoo

src/uu/top/src/picker.rs

@@ -432,6 +432,15 @@ fn mem(pid: u32, _stat: Stat) -> Box<dyn Column> {
     )
 }
 
+pub(crate) fn get_cgroup(pid: u32) -> String {
+    let path = PathBuf::from_str(&format!("/proc/{pid}/cgroup")).unwrap();
+    if let Ok(file) = File::open(path) {
+        read_to_string(file).unwrap()
+    } else {
+        String::new()
+    }
+}
+
 pub(crate) fn get_command(pid: u32, full_command_line: bool) -> String {
     let f = |cmd: &[OsString]| -> String {
         let binding = cmd

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

@@ -4,7 +4,7 @@
 // file that was distributed with this source code.
 
 use crate::header::Header;
-use crate::picker::get_command;
+use crate::picker::{get_cgroup, get_command};
 use crate::platform::get_numa_nodes;
 use crate::tui::stat::{CpuValueMode, TuiStat};
 use crate::Filter::{EUser, User};
@@ -98,6 +98,34 @@ pub fn handle_input(
                 data.write().unwrap().1 = ProcList::new(settings, &tui_stat.read().unwrap());
                 should_update.store(true, Ordering::Relaxed);
             }
+            Event::Key(KeyEvent {
+                code: KeyCode::Char('g'),
+                modifiers: KeyModifiers::CONTROL,
+                ..
+            }) => {
+                let mut data = data.write().unwrap();
+                if data.2.is_some() {
+                    data.2 = None;
+                } else {
+                    let tui_stat = tui_stat.read().unwrap();
+                    let mut nth = tui_stat.list_offset;
+                    if data.1.collected.is_empty() {
+                        return false;
+                    }
+                    if data.1.collected.len() <= nth {
+                        nth = data.1.collected.len() - 1;
+                    }
+                    let pid = data.1.collected[nth].0;
+                    let title = format!(
+                        "control groups for pid {}, {}",
+                        pid,
+                        get_command(pid, false)
+                    );
+                    let content = get_cgroup(pid);
+                    data.2 = Some(InfoBar { title, content });
+                }
+                should_update.store(true, Ordering::Relaxed);
+            }
             char!('I') => {
                 {
                     let mut stat = tui_stat.write().unwrap();
@@ -111,7 +139,6 @@ pub fn handle_input(
                 data.write().unwrap().1 = ProcList::new(settings, &tui_stat.read().unwrap());
                 should_update.store(true, Ordering::Relaxed);
             }
-
             Event::Key(KeyEvent {
                 code: KeyCode::Char('k'),
                 modifiers: KeyModifiers::CONTROL,