Re: [PATCH v2 5/5] mkfs.xfs: add configuration file parsing support using our own parser

From: "Luis R. Rodriguez" <mcgrof@kernel.org>
To: Dave Chinner <david@fromorbit.com>
Cc: "Luis R. Rodriguez" <mcgrof@kernel.org>,
	sandeen@sandeen.net, linux-xfs@vger.kernel.org,
	darrick.wong@oracle.com, jack@suse.com, jeffm@suse.com,
	okurz@suse.com, lpechacek@suse.com, jtulak@redhat.com
Subject: Re: [PATCH v2 5/5] mkfs.xfs: add configuration file parsing support using our own parser
Date: Tue, 22 May 2018 12:37:26 -0700	[thread overview]
Message-ID: <20180522193726.GA24593@garbanzo.do-not-panic.com> (raw)
In-Reply-To: <20180518004404.GF23861@dastard>

On Fri, May 18, 2018 at 10:44:04AM +1000, Dave Chinner wrote:
> On Thu, May 17, 2018 at 12:27:00PM -0700, Luis R. Rodriguez wrote:
> > +}
> > +
> > +static enum parse_line_type parse_get_line_type(const char *line, char *tag,
> > +						bool *value)
> > +{
> > +	int ret;
> > +	unsigned int uint_value;
> > +
> > +	memset(tag, 0, 80);
> 
> Why? This should be done in the caller, and if there's a fixed
> buffer size, then please use a #define.

I've modified to use 'm' specifier on scanf().

Using 'm' tells scanf() to allocate a buffer for us, this is easier as
we then enable the parser to do as it sees fit so long as the patterns
match. We just have to later free it after use.

That removes the need to memset() and stick to a predefined buffer sizes
for the tags (section or subopt name).

  Luis