1 files changed, 51 insertions, 1 deletions

diff --git a/arch/x86_64/hal/obj.c b/arch/x86_64/hal/obj.c
index af0491a..cb0e13d 100644
--- a/arch/x86_64/hal/obj.c
+++ b/arch/x86_64/hal/obj.c
@@ -16,6 +16,18 @@ obj_take(jove_obj_t *obj)
     return (jove_owned_obj_t*)obj;
 }
 
+jove_owned_obj_t*
+obj_trytake(jove_obj_t *obj)
+{
+    if((uintptr_t)obj < IDENT_VIRT_BASE) {
+        reterr(EBADOBJ);
+    }
+    if(try_take_mutex(&obj->lock)) {
+        reterr(EBUSY);
+    }
+    return (jove_owned_obj_t*)obj;
+}
+
 jove_obj_t*
 obj_release(jove_owned_obj_t *obj)
 {
@@ -97,16 +109,32 @@ objdir_getlocal(
 }
 
 jove_owned_obj_t*
+objdir_trygetlocal(
+        jove_owned_obj_t *objdir_obj, 
+        uint16_t entry)
+{
+    if(obj_gettype_linked(objdir_obj) != JOVE_OBJ_OBJDIR) {
+        reterr(EBADOBJ);
+    }
+    if(entry >= JOVE_OBJDIR_ENTRIES) {
+        reterr(EBADPATH);
+    }
+
+    jove_objdir_t *objtab = obj_deref_linked(objdir_obj);
+    return obj_trytake(&objtab->entries[entry]);
+}
+
+jove_owned_obj_t*
 objdir_getobj(
         jove_owned_obj_t *objdir_obj, 
         const uint16_t *path, 
         size_t path_len)
 {
+    errno = 0;
     if(path_len == 0) {
         return objdir_obj;
     }
     {
-        errno = 0;
         jove_owned_obj_t *child_objdir = objdir_getlocal(objdir_obj, path[0]);
         if(child_objdir == 0) {
             reterr(EBADPATH);
@@ -118,3 +146,25 @@ objdir_getobj(
     }
 }
 
+jove_owned_obj_t*
+objdir_trygetobj(
+        jove_owned_obj_t *objdir_obj, 
+        const uint16_t *path, 
+        size_t path_len)
+{
+    errno = 0;
+    if(path_len == 0) {
+        return objdir_obj;
+    }
+    {
+        jove_owned_obj_t *child_objdir = objdir_trygetlocal(objdir_obj, path[0]);
+        if(child_objdir == 0) {
+            return 0;
+        }
+
+        jove_owned_obj_t *target_obj = objdir_trygetobj(child_objdir, path + 1, path_len - 1);
+        obj_release(child_objdir);
+        return target_obj;
+    }
+}
+