Actually replied to the mailing list this time...

>Have you considered just not unsetting caseglob?

Brilliant solution.
"Doctor, it hurts when I do this."
"Then don't do that."

As for the compliant version, here is a much more "polite" version which
also avoids the awkward checks if lock != NULL (at the cost of reformatting
O.o).

/* Check for search permissions. If we don't have them, get out. */
if (access(fn, X_OK) != 0) {
    return;
}
/* Check for read permissions. If we have them, try to open the directory.
*/
if (access(fn, R_OK) == 0) {
    DIR *lock = diropen(fn);
    if (lock == NULL)
        return;

    while (...) { ... }
    closedir(lock);
}
if (subdirs) { ... }


% chmod 111 ..
% echo $PWD/*
/tmp/inaccessible/a/a /tmp/inaccessible/a/b /tmp/inaccessible/a/c
% chmod 000 ..
% echo $PWD/*
zsh: no matches found: /tmp/inaccessible/a/*

This matches the POSIX behavior of requiring parent directories to be
searchable, and is a little more respectful to filesystem permissions.

On Tue, Jan 12, 2021, 8:58 PM Devin Hussey <husseydevin@gmail.com> wrote:

> >Have you considered just not unsetting caseglob?
>
> Brilliant solution.
> "Doctor, it hurts when I do this."
> "Then don't do that."
>
> As for the compliant version, here is a much more "polite" version.
>
> This matches the behavior of the POSIX globs: with a non searchable
> directory, it returns no match, but doesn't require read access for parent
> directories.
>
> DIR *lock = NULL;
>
> /* Check for search permissions. If we don't have them, get out. */
> if (access(fn, X_OK) != 0) {
>     return;
> }
> /* Check for read permissions. If we have them, try to open the directory.
> */
> if (access(fn, R_OK) == 0) {
>     lock = diropen(fn);
>     /* Error */
>     if (lock == NULL)
>         return;
> }
> while (lock != NULL &&...
>
> % chmod 111 ..
> % echo $PWD/*
> /tmp/inaccessible/a/a /tmp/inaccessible/a/b /tmp/inaccessible/a/c
> % chmod 000 ..
> % echo $PWD/*
> zsh: no matches found: /tmp/inaccessible/a/*
>