Add new thread exception (untested)

src/kernel/thread.rs

@@ -1,3 +1,5 @@
+use std::{rc::Rc, cell::RefCell};
+
 use super::{process::Process, system::ObjectType};
 use crate::{simulator::machine::{NUM_INT_REGS, NUM_FP_REGS, STACK_REG}};
 
@@ -22,7 +24,7 @@ pub struct ThreadContext {
 #[derive(PartialEq, Debug)]
 pub struct Thread {
     name: String,
-    pub process: Option<Process>,
+    pub process: Option<Rc<RefCell<Process>>>,
     pub thread_context: ThreadContext,
     pub stack_pointer: i32,
     object_type: ObjectType
@@ -66,6 +68,12 @@ impl Thread {
         self.name.clone()
     }
 
+    /// Return reference to an optional Process
+    /// can be None if Thread hasn't been initialize
+    pub fn get_process_owner(&self) -> &Option<Rc<RefCell<Process>>> {
+        &self.process
+    }
+
 }
 
 impl Drop for Thread {