dfs_rename should work when the new file exsits about rt-thread HOT 3 CLOSED

int dfs_file_rename(const char *oldpath, const char *newpath)
{
    int result;
    struct dfs_filesystem *oldfs, *newfs;
    char *oldfullpath, *newfullpath;

    result = DFS_STATUS_OK;
    newfullpath = RT_NULL;
    oldfullpath = RT_NULL;

    oldfullpath = dfs_normalize_path(RT_NULL, oldpath);
    if (oldfullpath == RT_NULL)
    {
        result = -DFS_STATUS_ENOENT;
        goto __exit;
    }

    newfullpath = dfs_normalize_path(RT_NULL, newpath);
    if (newfullpath == RT_NULL)
    {
        result = -DFS_STATUS_ENOENT;
        goto __exit;
    }

    oldfs = dfs_filesystem_lookup(oldfullpath);
    newfs = dfs_filesystem_lookup(newfullpath);

    if (oldfs == newfs)
    {
        if (oldfs->ops->rename == RT_NULL)
        {
            result = -DFS_STATUS_ENOSYS;
        }
        else
        {
            if (oldfs->ops->flags & DFS_FS_FLAG_FULLPATH)
                result = oldfs->ops->rename(oldfs, oldfullpath, newfullpath);
            else
                /* use sub directory to rename in file system */
                result = oldfs->ops->rename(oldfs,
                                            dfs_subdir(oldfs->path, oldfullpath),
                                            dfs_subdir(newfs->path, newfullpath));
        }
    }
    else
    {
        result = -DFS_STATUS_EXDEV;
    }

__exit:
    rt_free(oldfullpath);
    rt_free(newfullpath);

    /* not at same file system, return EXDEV */
    return result;
}