Wireshark · Ethereal-dev: Re: [Ethereal-dev] While we're on the subject of new frametypes...

[Devin Heitmueller <dheitmueller@xxxxxxxxxxx>]

Ah!  I see the problem now.  If I'm reading you right, the issue is that
the hf_register_info structure is hard-coded at compile time.  

Now that I understand your argument, I totally agree that your proposal
is the right way to go.

Sorry for the confusion,

-Devin

On Fri, 2002-12-13 at 14:50, Guy Harris wrote:
> On Fri, Dec 13, 2002 at 10:33:17AM -0500, Devin Heitmueller wrote:
> > Since there are numerous variants of extended
> > ASCII, it should be left to the dissector to decide which character set
> > they are using.  This means that we should add types like
> > FT_STRING_ISO8859-1 and FT_STRING_UCS2_LE.
> 
> That's precisely the idea that I said might not work.
> 
> What if a string's character set can only be determined at run time, as
> per
> 
> 	   Making the character set a property of the field might not
> 	   work - for example, that wouldn't work for OEM character sets
> 	   in SMB, as that'd have to be something set by an SMB
> 	   preference item at run time.  It might work for the Mac
> 	   character set in Appletalk, however.
> 
> The alternative I suggested, which also lets the dissector decide what
> character set is being used, was
> 
> 		perhaps have the byte-order argument to
> 		"proto_tree_add_item()" specify, for FT_STRING types,
> 		the character set and, in cases where a multi-byte
> 		character type can come in either byte order, the byte
> 		order;
> 
> 		add a character set+byte order argument to
> 		"proto_tree_add_string()"?
> 
> Then "proto_tree_add_item()" would perform conversation as necessary:
> 
> 	If the type (supplied in the field that's currently used only
> 	for byte order) is CHARSET_ISO8859-1, it would convert to UTF-8.
> 
> 	If it was CHARSET_UCS2|LITTLE_ENDIAN, it would convert to UTF-8.
> 
> 	If it was CHARSET_UCS2|BIG_ENDIAN, it would convert to UTF-8.
> 
> 	If it was CHARSET_ASCII, it would convert to UTF-8.
> 
> and so on
-- 
Devin Heitmueller
Senior Software Engineer
Netilla Networks Inc