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Date:   Tue, 10 Aug 2021 17:43:03 +0200
From:   Len Baker <len.baker@gmx.com>
To:     Andy Shevchenko <andy.shevchenko@gmail.com>,
        David Laight <David.Laight@ACULAB.COM>,
        Jonathan Cameron <Jonathan.Cameron@huawei.com>
Cc:     Len Baker <len.baker@gmx.com>,
        Lars-Peter Clausen <lars@metafoo.de>,
        Kees Cook <keescook@chromium.org>,
        linux-hardening@vger.kernel.org,
        linux-iio <linux-iio@vger.kernel.org>,
        Linux Kernel Mailing List <linux-kernel@vger.kernel.org>
Subject: Re: [PATCH v2] drivers/iio: Remove all strcpy() uses in favor of
 strscpy()
Message-ID: <20210810154303.GA2508@titan>
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Hi Andy, David and Jonathan

First of all thanks you very much for your code snippets ;)
More below.

On Tue, Aug 10, 2021 at 03:11:01PM +0300, Andy Shevchenko wrote:
> On Tue, Aug 10, 2021 at 3:06 PM Andy Shevchenko
> <andy.shevchenko@gmail.com> wrote:
> > On Mon, Aug 9, 2021 at 7:14 PM Len Baker <len.baker@gmx.com> wrote:
>
>
>
> > Even if we leave the logic as is, this might be better
> >
> > if (orient[0] =3D=3D '-')
> >    str =3D devm_kstrdup(dev, orient + 1, GFP_KERNEL);
>
> > else if (orient[0] !=3D '0' || orient[1] !=3D '\0')
> >    str =3D devm_kasprintf(dev, GFP_KERNEL, "-%s", orient);
> > else
> >    str =3D devm_kstrdup(dev, orient, GFP_KERNEL);

I think the above snippet is the right one: Is compact and easy
to understand.

>
> Or these two swapped for better reading
>
>  else if (orient[0] =3D=3D '0' **&& orient[1] =3D=3D '\0')
>     str =3D devm_kstrdup(dev, orient, GFP_KERNEL);
> else
>     str =3D devm_kasprintf(dev, GFP_KERNEL, "-%s", orient);
>
> And with a comment added that we negate the result according to the
> rules: 1) drop leading '-' (minus); 2) leave 0 as is; add leading '-'
> (minus).
>
> > if (!str)
> >    return -ENOMEM;

Also, I think that it is better to leave the logic as is and don't
try to use always the +/- sign.

Again thanks to all for the feedback.

Regards,
Len