[barcode] UPC-E decoding

[Alessandro Rubini]

Hello.

> a minor bug (or feature who knows): 

A feature. Note that "upc-a" and "upc-e" are treated as synonyms to
"upc".  The internal encoder accepts strings that are valid according
to UPC-A or UPC-E. Since the two sets are separate, there's no problem.

> From my point of view (maybe I am wrong) it should come back with an
> error message.

This would require treating the encoder as two separate encoders. I
don't think it's worth the effort.  Specifying which standard to use
is mainly needed for ambiguous strings (that can be encoded in
different ways).  I'd better think of UPC as a single standard, as
long as all substandards can act on distinct sets of strings.

/alessandro
-- 
Alessandro Rubini, free software developer.
Device drivers, embedded systems, courses.
http://ar.linux.it/