Fix exceptions with semaphore

src/utility/objaddr.rs

@@ -15,6 +15,7 @@ use crate::kernel::synch::{ Semaphore, Lock };
 /// A method allows to detect of an object corresponding to a given
 /// identifier exists; this is used to check the parameters of system
 /// calls.
+#[derive(PartialEq)]
 pub struct ObjAddr {
     last_id: i32,
     semaphores: HashMap<i32, Semaphore>,
@@ -47,12 +48,12 @@ impl ObjAddr {
     }
 
     /// Searches for a semaphore of id **id** in self
-    pub fn search_semaphore(&self, id: i32) -> Option<&mut Semaphore> {
+    pub fn search_semaphore(&mut self, id: i32) -> Option<&mut Semaphore> {
         self.semaphores.get_mut(&id)
     }
 
     /// Searches for a lock of id **id** in self
-    pub fn search_lock(&self, id:i32) -> Option<&mut Lock> {
+    pub fn search_lock(&mut self, id:i32) -> Option<&mut Lock> {
         self.locks.get_mut(&id)
     }