Received-SPF: pass (google.com: best guess record for domain of linux-kernel-owner@vger.kernel.org designates 209.132.180.67 as permitted sender) client-ip=209.132.180.67;
MIME-Version: 1.0
References: <20190729151454.9606-1-hslester96@gmail.com> <20190729191511.GB2023@amd>
In-Reply-To: <20190729191511.GB2023@amd>
From:   Chuhong Yuan <hslester96@gmail.com>
Date:   Thu, 1 Aug 2019 16:07:47 +0800
Message-ID: <CANhBUQ3beB_aHMJSy9G942oUo_BT=x0w3gB3Vip_-nJxVjqu8A@mail.gmail.com>
Subject: Re: [PATCH 07/12] power: Replace strncmp with str_has_prefix
To:     Pavel Machek <pavel@ucw.cz>
Cc:     "Rafael J . Wysocki" <rjw@rjwysocki.net>,
        Len Brown <len.brown@intel.com>, linux-pm@vger.kernel.org,
        LKML <linux-kernel@vger.kernel.org>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
Sender: linux-kernel-owner@vger.kernel.org
Precedence: bulk

Pavel Machek <pavel@ucw.cz> =E4=BA=8E2019=E5=B9=B47=E6=9C=8830=E6=97=A5=E5=
=91=A8=E4=BA=8C =E4=B8=8A=E5=8D=883:15=E5=86=99=E9=81=93=EF=BC=9A
>
> On Mon 2019-07-29 23:14:54, Chuhong Yuan wrote:
> > strncmp(str, const, len) is error-prone.
> > We had better use newly introduced
> > str_has_prefix() instead of it.
> >
> > Signed-off-by: Chuhong Yuan <hslester96@gmail.com>
> > ---
> >  kernel/power/hibernate.c | 8 ++++----
> >  kernel/power/main.c      | 2 +-
> >  2 files changed, 5 insertions(+), 5 deletions(-)
> >
> > diff --git a/kernel/power/hibernate.c b/kernel/power/hibernate.c
> > index cd7434e6000d..49d4bfdb2b67 100644
> > --- a/kernel/power/hibernate.c
> > +++ b/kernel/power/hibernate.c
> > @@ -1188,15 +1188,15 @@ static int __init resume_offset_setup(char *str=
)
> >
> >  static int __init hibernate_setup(char *str)
> >  {
> > -     if (!strncmp(str, "noresume", 8)) {
> > +     if (str_has_prefix(str, "noresume")) {
> >               noresume =3D 1;
> > -     } else if (!strncmp(str, "nocompress", 10)) {
> > +     } else if (str_has_prefix(str, "nocompress")) {
> >               nocompress =3D 1;
>
> Ok, old code is bad, too... but this makes the error visible. We do
> not want "noresumenextmonday" to set noresume =3D 1, right?
>

I am not clear about the semantic of the code.
Therefore, what is the right way to fix this error?

>                                                                 Pavel
>
> --
> (english) http://www.livejournal.com/~pavelmachek
> (cesky, pictures) http://atrey.karlin.mff.cuni.cz/~pavel/picture/horses/b=
log.html