Re: [PATCH v5 02/21] lib/vsprintf: Print time and date in human readable format via %pt

From: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
To: Geert Uytterhoeven <geert@linux-m68k.org>
Cc: Petr Mladek <pmladek@suse.com>,
	Alessandro Zummo <a.zummo@towertech.it>,
	Alexandre Belloni <alexandre.belloni@bootlin.com>,
	linux-rtc@vger.kernel.org, Arnd Bergmann <arnd@arndb.de>,
	Joe Perches <joe@perches.com>, Mark Salyzyn <salyzyn@android.com>,
	Linux Kernel Mailing List <linux-kernel@vger.kernel.org>,
	Rasmus Villemoes <rasmus.villemoes@prevas.dk>,
	Greg KH <gregkh@linuxfoundation.org>,
	Bartlomiej Zolnierkiewicz <b.zolnierkie@samsung.com>,
	Dmitry Torokhov <dmitry.torokhov@gmail.com>,
	Guan Xuetao <gxt@mprc.pku.edu.cn>, Ingo Molnar <mingo@kernel.org>,
	Jason Wessel <jason.wessel@windriver.com>,
	Jonathan Corbet <corbet@lwn.net>,
	Jon Hunter <jonathanh@nvidia.com>,
	Krzysztof Kozlowski <krzk@kernel.org>,
	"Rafael J. Wysocki" <rjw@rjwysocki.net>,
	Thierry Reding <thierry.reding@gmail.com>
Subject: Re: [PATCH v5 02/21] lib/vsprintf: Print time and date in human readable format via %pt
Date: Tue, 4 Dec 2018 18:38:49 +0200	[thread overview]
Message-ID: <20181204163849.GE10650@smile.fi.intel.com> (raw)
In-Reply-To: <CAMuHMdUXQX=Y6K5XZok38W75KSBM+5PNRMKMhavNG_JtbxoNAw@mail.gmail.com>

On Tue, Dec 04, 2018 at 05:16:58PM +0100, Geert Uytterhoeven wrote:
> On Tue, Dec 4, 2018 at 5:12 PM Andy Shevchenko
> <andriy.shevchenko@linux.intel.com> wrote:
> > On Tue, Dec 04, 2018 at 02:30:28PM +0100, Petr Mladek wrote:
> > > On Thu 2018-11-29 12:59:40, Andy Shevchenko wrote:
> > > > There are users which print time and date represented by content of
> > > > struct rtc_time in human readable format.
> > > >
> > > > Instead of open coding that each time introduce %ptR[dt][r] specifier.
> >
> > > > +static void __init
> > > > +struct_rtc_time(void)
> > > > +{
> > > > +}
> > >
> > > Just by chance, do you have any plans to add the test code? ;-)
> > >
> > > I understand that you did now want to spend time on it before
> > > the real change was accepted.
> >
> > You see, there were several iterations with no consensus on everything:
> > specifier format changed 3 times, for example.
> >
> > But it might be good idea to eventually add couple simple tests at some point.
> >
> > Is it a show stopper?
> 
> Can the user trigger formatting, and exploit a bug in the formatting code?

Might happen, it's a software at the end.
Do we need to revisit all formatting specifiers right now?

In any case, to be productive out of this discussion, I would like to gather
test cases you want to see.

-- 
With Best Regards,
Andy Shevchenko