RE: [PATCH v2 3/7] lib/hexdump.c: Optionally suppress lines of repeated bytes

["Alastair D'Silva" <alastair@d-silva.org>]

> -----Original Message-----
> From: Geert Uytterhoeven <geert@linux-m68k.org>
> Sent: Monday, 13 May 2019 5:01 PM
> To: Alastair D'Silva <alastair@au1.ibm.com>
> Cc: alastair@d-silva.org; Jani Nikula <jani.nikula@linux.intel.com>; Joonas
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> Subject: Re: [PATCH v2 3/7] lib/hexdump.c: Optionally suppress lines of
> repeated bytes
> 
> Hi Alastair,
> 
> Thanks for your patch!

And thanks for your politeness :)

> 
> On Wed, May 8, 2019 at 9:04 AM Alastair D'Silva <alastair@au1.ibm.com>
> wrote:
> > From: Alastair D'Silva <alastair@d-silva.org>
> >
> > Some buffers may only be partially filled with useful data, while the
> > rest is padded (typically with 0x00 or 0xff).
> >
> > This patch introduces a flag to allow the supression of lines of
> > repeated bytes,
> 
> Given print_hex_dump() operates on entities of groupsize (1, 2, 4, or 8)
> bytes, wouldn't it make more sense to consider repeated groups instead of
> repeated bytes?

Maybe, it would mean that subsequent addresses may not be a multiple of rowsize though, which is useful.

> > which are replaced with '** Skipped %u bytes of value 0x%x **'
> 
> Using a custom message instead of just "*", like "hexdump" uses, will require
> preprocessing the output when recovering the original binary data by
> feeding it to e.g. "xxd".
> This may sound worse than it is, though, as I never got "xxd" to work without
> preprocessing anyway ;-)

I think showing the details of the skipped values is useful when reading the output directly. In situations where binary extracts are desired, the feature can always be disabled.

-- 
Alastair D'Silva           mob: 0423 762 819
skype: alastair_dsilva     msn: alastair@d-silva.org
blog: http://alastair.d-silva.org    Twitter: @EvilDeece