controller: implement automatic exit when process has exited

controller/src/ctl/console.rs

@@ -1,5 +1,11 @@
-use anyhow::{anyhow, Result};
+use std::{process::exit, time::Duration};
 
+use anyhow::{anyhow, Result};
+use log::warn;
+use tokio::time::sleep;
+use xenstore::client::XsdInterface;
+
+use super::destroy::ControllerDestroy;
 use crate::console::XenConsole;
 
 use super::ControllerContext;
@@ -22,7 +28,24 @@ impl ControllerConsole<'_> {
         let domid = info.domid;
         let tty = self.context.xen.get_console_path(domid).await?;
         let console = XenConsole::new(&tty).await?;
-        console.attach().await?;
-        Ok(())
+
+        let dom_path = self.context.xen.store.get_domain_path(domid).await?;
+
+        tokio::task::spawn(async move {
+            if let Err(error) = console.attach().await {
+                warn!("failed to attach to console: {}", error);
+            }
+        });
+
+        let exit_code_path = format!("{}/krata/guest/exit-code", dom_path);
+        loop {
+            let Some(code) = self.context.xen.store.read_string(&exit_code_path).await? else {
+                sleep(Duration::from_secs(1)).await;
+                continue;
+            };
+            let mut destroy = ControllerDestroy::new(self.context);
+            destroy.perform(&domid.to_string()).await?;
+            exit(code.parse::<i32>()?);
+        }
     }
 }