sys/link.c


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#include "link.h"
#include "arch/x86_64/hal/obj.h"
#include "sys/objdir.h"
#include "hal/memory.h"
#include "lib/printf.h"
#include "jove.h"


jove_perm_obj_t 
link_traverse(jove_owned_obj_t *link)
{
    jove_perm_obj_t perm_obj = { .obj = link, .permissions = JOVE_PERM_ALL };

    while(obj_gettype(perm_obj.obj) == JOVE_OBJ_LINK) {
        jove_link_obj_t *link = obj_deref(perm_obj.obj);
        perm_obj.permissions &= link_getperm(link);
        
        jove_owned_obj_t *linked_obj = link_deref(link);
        obj_release(perm_obj.obj);
        perm_obj.obj = linked_obj;
    }
    return perm_obj;
}

jove_perm_obj_t 
link_traverse_objdir(
        jove_obj_t *objdir,
        size_t pathlen,
        objpath_part_t *path)
{
    jove_owned_obj_t *objdir_obj = obj_take(objdir);
    jove_perm_obj_t perm_obj = link_traverse(objdir_obj);
    obj_release(objdir_obj);

    if(pathlen == 0) return perm_obj;

    jove_owned_obj_t *child_obj = objdir_getlocal(obj_release(perm_obj.obj), path[0]);
    perm_obj.obj = child_obj;
    
    jove_perm_obj_t traverse_obj = link_traverse_objdir(obj_release(child_obj), pathlen - 1, &path[1]);
    if(traverse_obj.obj != child_obj) {
        obj_release(perm_obj.obj);
    }
    traverse_obj.permissions &= perm_obj.permissions;

    return traverse_obj;
}