From mboxrd@z Thu Jan  1 00:00:00 1970
From: Junio C Hamano <gitster@pobox.com>
Subject: Re: [PATCH] general style: replaces memcmp() with proper starts_with()
Date: Thu, 13 Mar 2014 10:47:28 -0700
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Cc: Jeff King <peff@peff.net>,
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To: David Kastrup <dak@gnu.org>
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In-Reply-To: <877g7yipf9.fsf@fencepost.gnu.org> (David Kastrup's message of
	"Thu, 13 Mar 2014 07:27:22 +0100")
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David Kastrup <dak@gnu.org> writes:

> Junio C Hamano <gitster@pobox.com> writes:
>
>> Taking two random examples from an early and a late parts of the
>> patch:
>>
>> --- a/builtin/cat-file.c
>> +++ b/builtin/cat-file.c
>> @@ -82,7 +82,7 @@ static int cat_one_file(int opt, const char *exp_type, const char *obj_name)
>>  				enum object_type type;
>>  				unsigned long size;
>>  				char *buffer = read_sha1_file(sha1, &type, &size);
>> -				if (memcmp(buffer, "object ", 7) ||
>> +				if (!starts_with(buffer, "object ") ||
>
> [...]
>
>> The original hunks show that the code knows and relies on magic
>> numbers 7 and 8 very clearly and there are rooms for improvement.
>
> Like: what if the file is empty?

Yes.