Re: [Libexif-devel] Need some help with adding support for extra canon makernotes

[Marcus M. <mei...@su...>]

On Wed, Sep 06, 2006 at 03:39:30PM +0200, Jef Driesen wrote:
> Jan Patera wrote:
> >> case MNOTE_CANON_TAG_FOCAL_LENGTH:
> >>     CF (entry->format, EXIF_FORMAT_SHORT, val, maxlen);
> >>     n = exif_get_short (data, entry->order) / 2;
> >>     if (t >= n) return NULL;
> >>     CC (entry->components, n, val, maxlen);
> >>     vs = exif_get_short (entry->data + 2 + t * 2, entry->order);
> >>     snprintf (buf, sizeof (buf), "0x%04x", vs);
> >>     strncpy (val, buf, maxlen - strlen (val));
> >>     break;
> >>
> >> But when I run the exif commandline utility, an error is reported for
> >> the new tag:
> >>
> >> Focal type          |Invalid number of components (4, expected 1).
> >>
> >> What am I doing wrong here?
> > 
> > 
> > this message is printed by the CC macro. It checks whether
> > 1st & 2nd arguments are equal. apparently entry->components is 4,
> > but n is only 1.
> 
> I knew it was reported by the CC macro, but I don't understand why it is
> happening. It is exactly the same code as is used for
> MNOTE_CANON_TAG_SETTINGS_1 (which also has multiple components), but no
> error there! Probably I forgot to add some code somewhere else, but I
> don't see it.

Just a wild guess:
Did you adjust mnote_canon_entry_count_values() too?

Ciao, Marcus