RE: [PATCH 3/4] lib/hexdump.c: Replace ascii bool in hex_dump_to_buffer with flags

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

> -----Original Message-----
> From: David Laight <David.Laight@ACULAB.COM>
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> Subject: RE: [PATCH 3/4] lib/hexdump.c: Replace ascii bool in
> hex_dump_to_buffer with flags
> 
> From: Alastair D'Silva
> > Sent: 15 April 2019 11:45
> ...
> > > Although I think you'd want a 'no hex' flag to suppress the hex.
> > >
> > > Probably more useful flags are ones to suppress the address column.
> >
> > This is already supported by the prefix_type parameter - are you
> > proposing that we eliminate the parameter & combine it with flags?
> 
> I was looking at the flags on one of my hexdump() functions...
> 
> > > I've also used flags to enable (or disable) suppression of multiple
> > > lines of zeros of constant bytes.
> > > In that case you may want hexdump to return the flags for the next
> > > call when a large buffer is being dumped in fragments.
> >
> > I'm afraid I don't quite follow here, hex_dump_to_buffer doesn't alter
> > the flags, so the caller already knows it.
> 
> If you are suppressing lines of zeros and dumping a buffer in several blocks
> then subsequent calls need to know that the last line of the previous call was
> suppressed zeros - and carry on with the same suppressed block.

Why wouldn't you do this with a single call to print_hex_dump? (that is where the repeated lines are suppressed)

That will already take chunks of the buffer until the whole thing is output, in what situation do you see a caller chunking the access themselves?

-- 
Alastair D'Silva           mob: 0423 762 819
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