1 files changed, 39 insertions, 17 deletions

diff --git a/sys/link.c b/sys/link.c
index 5be9457..592fe8f 100644
--- a/sys/link.c
+++ b/sys/link.c
@@ -2,31 +2,23 @@
 #include "arch/x86_64/hal/obj.h"
 #include "hal/memory.h"
 
-void*
-obj_deref_linked(jove_owned_obj_t *obj)
+uint8_t 
+link_gettype(jove_owned_obj_t *obj)
 {
-    switch(obj_gettype(obj)) {
-        case JOVE_OBJ_LINK: return obj_deref_linked(link_deref(obj));
-        default: return obj_deref(obj);
-    }
+    return obj_gettype(link_deref(obj));
 }
 
 uint8_t 
-obj_gettype_linked(jove_owned_obj_t *obj)
+link_getperm(jove_owned_obj_t *link)
 {
-    switch(obj_gettype(obj)) {
-        case JOVE_OBJ_LINK: return obj_gettype_linked(link_deref(obj));
-        default: return obj_gettype(obj);
-    }
+    struct obj_link *linkval = obj_deref(link);
+    return linkval->permissions;
 }
 
 uint64_t 
-obj_getvalue_linked(jove_owned_obj_t *obj)
+link_getvalue(jove_owned_obj_t *obj)
 {
-    switch(obj_gettype(obj)) {
-        case JOVE_OBJ_LINK: return obj_getvalue_linked(link_deref(obj));
-        default: return obj_getvalue(obj);
-    }
+    return obj_getvalue(link_deref(obj));
 }
 
 jove_owned_obj_t*
@@ -36,11 +28,41 @@ link_deref(jove_owned_obj_t *link)
     return obj_take(&linkval->obj);
 }
 
-jove_owned_obj_t *link_new(jove_obj_t *tgt, jove_owned_obj_t *dst)
+jove_owned_obj_t*
+link_try_deref(jove_owned_obj_t *link)
+{
+    struct obj_link *linkval = obj_deref(link);
+    return obj_trytake(&linkval->obj);
+}
+
+jove_perm_obj_t 
+link_traverse(jove_owned_obj_t *link, lockstack_t *lockstack)
+{
+    jove_perm_obj_t perm_obj = { .obj = link, .permissions = JOVE_PERM_ALL };
+    while(obj_gettype(perm_obj.obj) == JOVE_OBJ_LINK) {
+        perm_obj.permissions &= link_getperm(perm_obj.obj);
+        perm_obj.obj = lockstack_push(lockstack, link_deref(perm_obj.obj));
+    }
+    return perm_obj;
+}
+
+jove_perm_obj_t 
+link_try_traverse(jove_owned_obj_t *link, lockstack_t *lockstack)
+{
+    jove_perm_obj_t perm_obj = { .obj = link, .permissions = JOVE_PERM_ALL };
+    while(perm_obj.obj != NULL && obj_gettype(perm_obj.obj) == JOVE_OBJ_LINK) {
+        perm_obj.permissions &= link_getperm(perm_obj.obj);
+        perm_obj.obj = lockstack_push(lockstack, link_deref(perm_obj.obj));
+    }
+    return perm_obj;
+}
+
+jove_owned_obj_t *link_new(jove_obj_t *tgt, jove_owned_obj_t *dst, uint16_t permissions)
 {
     struct obj_link *linkval = obj_deref(dst);
     linkval->obj = *tgt;
     linkval->refcount = 2;
+    linkval->permissions = permissions;
 
     {
         jove_owned_obj_t *tgt_owned = obj_take(tgt);