Re: new module: relpath

[Eli Zaretskii]

> Date: Mon, 18 Jun 2012 09:39:26 -0600
> From: Eric Blake <address@hidden>
> CC: Akim Demaille <address@hidden>, address@hidden
> 
> >> +  while (*path1 && *path2)
> >> +    {
> >> +      if (*path1 != *path2)
> > 
> > This comparison should be case-insensitive for MS-Windows.
> 
> Shouldn't normalization already guarantee canonical case, so that by the
> time we get here, case-sensitive comparison is correct?

Maybe, but it's not entirely clear to me it is a good idea to rely on
that.  There's more than one way of canonicalizing a file name.  Even
if you document that gnulib's functions should be used for that, how
those functions work may change some day.  So I think it would be
better to be less dependent on what exactly a canonical file name is
on MS-Windows.

> >> +char *
> >> +convert_abs_rel (const char *from, const char *target)
> >> +{
> >> +  char *realtarget = canonicalize_filename_mode (target, CAN_MISSING);
> >> +  char *realfrom = canonicalize_filename_mode (from, CAN_MISSING);
> > 
> > AFAICT, canonicalize_filename_mode can return NULL, but the rest of
> > the code doesn't cope with that.
> 
> No, canonicalize_filename_mode is GPL because it calls xalloc() and dies
> rather than return NULL.

Maybe I'm looking at the wrong source file in gnulib. but I see these
at the beginning of canonicalize_filename_mode:

  if (name == NULL)
    {
      errno = EINVAL;
      return NULL;
    }

  if (name[0] == '\0')
    {
      errno = ENOENT;
      return NULL;
    }

  if (name[0] != '/')
    {
      rname = xgetcwd ();
      if (!rname)
        return NULL;