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From: Rob Clark <robdclark@gmail.com>
Date: Sat, 5 Nov 2016 12:49:01 -0400
Message-ID: <CAF6AEGuEB82fjZ_YF61MAAqU=8ahXuMo06MN0_ZuWY5fkyHnoQ@mail.gmail.com>
Subject: Re: [PATCH] drm: move allocation out of drm_get_format_name()
To: Eric Engestrom <eric@engestrom.ch>
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On Sat, Nov 5, 2016 at 12:38 PM, Eric Engestrom <eric@engestrom.ch> wrote:
> On Saturday, 2016-11-05 13:11:36 +0100, Christian König wrote:
>> Am 05.11.2016 um 02:33 schrieb Eric Engestrom:
>> > +typedef char drm_format_name_buf[32];
>>
>> Please don't use a typedef for this, just define the maximum size of
>> characters the function might write somewhere.
>>
>> See the kernel coding style as well:
>> > In general, a pointer, or a struct that has elements that can reasonably
>> > be directly accessed should **never** be a typedef.
>>
>
> I would normally agree as I tend to hate typedefs ($DAYJOB {ab,mis}uses
> them way too much), and your way was what I wrote at first, but Rob Clark's
> typedef idea makes it much harder for someone to allocate a buffer of
> the wrong size, which IMO is good thing here.

IMHO I would make a small test program to verify this actually helps
the compiler catch problems.  And if it does, I would stick with it.
The coding-style should be guidelines, not something that supersedes
common sense / practicality.

That is my $0.02 anyways.. if others vehemently disagree and want to
dogmatically stick to the coding-style guidelines, ok then.  OTOH, if
this approach doesn't help the compiler catch issues, then it isn't
worth it.

BR,
-R

> I can rewrite the typedef out if you think it's better.
>
> Cheers,
>   Eric
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