[PATCH 1/3] vsprintf: add support for printing raw buffers as hex (%*ph)

[Ahmad Fatoum]

Hello Sascha,

On 14.12.21 08:27, Sascha Hauer wrote:
> On Tue, Dec 14, 2021 at 07:57:01AM +0100, Ahmad Fatoum wrote:
>> On 13.12.21 23:28, Sascha Hauer wrote:
>>> On Thu, Dec 09, 2021 at 11:57:06AM +0100, Ahmad Fatoum wrote:
>>>> Import from Linux support for printing buffers as a hex string
>>>> with a certain separator. For larger buffers consider using
>>>> print_hex_dump(). Examples:
>>>>
>>>>   %*ph	00 01 02  ...  3f
>>>>   %*phC	00:01:02: ... :3f
>>>>   %*phD	00-01-02- ... -3f
>>>>   %*phN	000102 ... 3f
>>>>
>>>> Signed-off-by: Ahmad Fatoum <a.fatoum at pengutronix.de>
>>>> ---
>>>>  lib/Kconfig    |  3 +++
>>>>  lib/vsprintf.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++
>>>>  2 files changed, 53 insertions(+)
>>>>
>>>> diff --git a/lib/Kconfig b/lib/Kconfig
>>>> index 718033e56e64..27e7bea6852f 100644
>>>> --- a/lib/Kconfig
>>>> +++ b/lib/Kconfig
>>>> @@ -166,6 +166,9 @@ config PRINTF_UUID
>>>>  config PRINTF_WCHAR
>>>>  	bool
>>>>  
>>>> +config PRINTF_HEXSTR
>>>> +	bool
>>>
>>> So hexdumps are silently ignored when this option is disabled. Not sure
>>> if this should really be configurable, but I think when it is
>>> configurable it should be default y to avoid surprises.
>>
>> It will be printed as a raw pointer when the option is disabled.
>> There's no code in-tree that uses this format specifier yet,
>> so I prefer to not make this the default and increase binary size.
> 
> Ok for now, but we should revise it once this actually gets used.

This is still left after a rebase.

Cheers,
Ahmad

> 
> Sascha
> 
> 


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