From mboxrd@z Thu Jan  1 00:00:00 1970
From: David Kastrup <dak@gnu.org>
Subject: Re: [PATCH] general style: replaces memcmp() with proper starts_with()
Date: Thu, 13 Mar 2014 07:27:22 +0100
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Cc: Jeff King <peff@peff.net>,
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To: Junio C Hamano <gitster@pobox.com>
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In-Reply-To: <xmqqha73jb6q.fsf@gitster.dls.corp.google.com> (Junio C. Hamano's
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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?

-- 
David Kastrup