Re: [PATCH] unpack-trees: do not abort when overwriting an existing file with the same content

From: Junio C Hamano <gitster@pobox.com>
Date: Jan 20, 2013, 18:35 UTC
Message-ID: <7va9s3n1my.fsf@alter.siamese.dyndns.org>
In-Reply-To: <1358594648-26851-1-git-send-email-pclouds@gmail.com>

Nguyễn Thái Ngọc Duy  <pclouds@gmail.com> writes:

> +	/*
> +	 * If it has the same content that we are going to write down,

write down???

> +	 * there's no point in complaining. We still overwrite it in the
> +	 * end though. Permission is not checked so it may be lost.
> +	 */

That is a regression, isn't it? Is it too cumbersome to avoid losing the permission bits by stopping in that case?

Show 24 quoted lines

> +	if (ce &&
> +	    S_ISREG(st->st_mode) && S_ISREG(ce->ce_mode) &&
> +	    st->st_size < 1024 * 1024 && /* should be configurable */
> +	    sha1_object_info(ce->sha1, &ce_size) == OBJ_BLOB &&
> +	    ce_size == st->st_size) {
> +		void *buffer = NULL;
> +		unsigned long size;
> +		enum object_type type;
> +		struct strbuf sb = STRBUF_INIT;
> +		int matched =
> +			strbuf_read_file(&sb, ce->name, ce_size) == ce_size &&
> +			(buffer = read_sha1_file(ce->sha1, &type, &size)) != NULL &&
> +			type == OBJ_BLOB &&
> +			size == ce_size &&
> +			!memcmp(buffer, sb.buf, size);
> +		free(buffer);
> +		strbuf_release(&sb);
> +		if (matched)
> +			return 0;
> +	}
> +
>  	return o->gently ? -1 :
>  		add_rejected_path(o, error_type, name);
>  }