Re: [PATCH v4 05/12] sequencer.c: recognize "(cherry picked from ..." as part of s-o-b footer

From: Jonathan Nieder <jrnieder@gmail.com>
Date: Feb 12, 2013, 19:45 UTC
Message-ID: <20130212194502.GA12240@google.com>
In-Reply-To: <511A98C0.70201@nvidia.com>

Brandon Casey wrote:

> On 2/12/2013 11:13 AM, Junio C Hamano wrote:
>> Brandon Casey <drafnel@gmail.com> writes:

Show 14 quoted lines

>>> +static int is_cherry_picked_from_line(const char *buf, int len)
>>> +{
>>> +	/*
>>> +	 * We only care that it looks roughly like (cherry picked from ...)
>>> +	 */
>>> +	return len > strlen(cherry_picked_prefix) + 1 &&
>>> +		!prefixcmp(buf, cherry_picked_prefix) && buf[len - 1] == ')';
>>> +}
>>
>> Does the first "is it longer than the prefix?" check matter?  If it
>> is not, prefixcmp() would not match anyway, no?
>
> Probably not in practice, but technically we should only be accessing
> len characters in buf even though buf may be longer than len.

Yep. Technically the buf[len - 1] == ')' check is enough to avoid false positives, but if it and the 'len' check were dropped then this would be checking that buf is a "(cherry-picked from" line instead of checking that its first 'len' bytes are one.

So it's just paranoid futureproofing. In the long term, it would be nice to drop the "number of bytes to ignore at the end" argument to append_signoff to avoid having to think about this kind of thing.

Jonathan