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

[Alastair D'Silva]

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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 11:07
> ...
> > In the above example the author only wants the hex output, while in
> > other situations, both hex & ASCII output is desirable. If you just
> > want ASCII output, the caller should just use a printk or one of it's
> wrappers.
> 
> Hexdump will 'sanitise' the ASCII.
> 

This is functionality that doesn't exist in the current hexdump implementation (you always get the hex version).

I think a better option would be to factor out the sanitisation and expose that as a separate function.

> 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'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. 

-- 
Alastair D'Silva           mob: 0423 762 819
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