Re: Re: -e vs. -x, revisited

[Andrew Brown <atatat () atatdot net>]

> > actually, it oughta be simpler than you think.  provided that all the
> > functions that may end up being returned from lookup_printer() set
> > packetp and snapend (as it seems they do), then one could simply
> > change default_print_unaligned as follows:
>
> Unfortunately, "default_print()" is used for other purposes - if neither
> "-x" nor "-q" is specified, the payload of the packet is often printed
> in hex if it wasn't printed by any dissector, and in that case I suspect
> the intent is to have it print only the payload, not the link-layer
> header.

i think i disagree.  if i have asked to see the link layer headers,
then the default_print() routine should print them.  the alternative
is either (a) sometimes you get them and sometimes you don't depending
on whether or not the dissector printed a packet dump, or (b)
sometimes you get two dumps of the packet (again, depending on the
dissector).

> (BTW, as per another recent discussioin, that means multi-line output
> even if "-v" isn't specified....)

we're already pretty much in that boat if the dissector calls
default_print(), right?

> It also struck me as a bit ugly to make "default_print_unaligned()"
> ignore its arguments, and use a global variable, if "-e" was specified -
> and, besides, that global variable no longer exists (I just checked in a
> change to get rid of "packetp").

perhaps it's a tad ugly, but it's certainly simpler.  see below.

> So I checked in a change to add a new "default_print_packet()" routine,
> which takes a pointer to the beginning of the raw packet data (*not*
> skipping the link-layer header), the number of bytes of raw packet data
> captured, and the size of the link-layer header; if "-e" is specified,
> it prints the raw packet data, and if it's not specified, it prints the
> part of the raw packet data past the link-layer header, if there is any.
> I also changed the "xxx_if_print()" routines to call that routine if
> "xflag" is set.

if (1) default_print_packet() were allowed to ignore its arguments so
that it could behave "properly" as per the given flags, (2) it set a
flag once called, that we could clear somewhere else, (3) a shim layer
was added in between pcap and the xxx_if_print() routines, then (4)
you could remove all xflag processing from all the xxx_if_print()
routines.  *that* sounds decidedly not ugly.

-- 
|-----< "CODE WARRIOR" >-----|
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twofsonet () graffiti com (Andrew Brown)                that goes *ping*!"
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