On Sat, Oct 26, 2019 at 2:58 PM Aleksa Sarai [off-list ref] wrote:

+       /* LOOKUP_IN_ROOT treats absolute paths as being relative-to-dirfd. */
+       if (flags & LOOKUP_IN_ROOT)
+               while (*s == '/')
+                       s++;
+
        /* Figure out the starting path and root (if needed). */
        if (*s == '/') {
                error = nd_jump_root(nd);

So I'm still hung up on this.

I guess I can't help it, but I look at the above, and it makes me go
"whoever wrote those tests wasn't thinking".

It just annoys me how it tests for '/' completely unnecessarily.

If LOOKUP_IN_ROOT is true, we know the subsequent test for '/' is not
going to match, because we just removed it. So I look at that code and
go "that code is doing stupid things".

That's why I suggested moving the LOOKUP_IN_ROOT check inside the '/' test.

Alternatively, just make the logic be

        if (flags & LOOKUP_IN_ROOT) {
               .. remove '/'s ...
        } else if (*s == '/') {
                .. handl;e root ..

and remove the next "else" clause

    Linus