From mboxrd@z Thu Jan  1 00:00:00 1970
From: Wolfgang Denk <wd@denx.de>
Date: Mon, 12 Jun 2017 09:45:57 +0200
Subject: [U-Boot] [PATCH v6 3/3] GPT: provide commands to selectively
	rename partitions
In-Reply-To: <1497137617-772-1-git-send-email-alison@peloton-tech.com>
References: <20170610065138.2410A120BB0@gemini.denx.de>
 <1497137617-772-1-git-send-email-alison@peloton-tech.com>
Message-ID: <20170612074557.E32A3120432@gemini.denx.de>
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To: u-boot@lists.denx.de

Dear Alison,

In message <1497137617-772-1-git-send-email-alison@peloton-tech.com> you wrote:
> 
> This patch provides support in u-boot for renaming GPT
> partitions.  The renaming is accomplished via new 'gpt swap'
> and 'gpt rename' commands.

Thanks.

One question: can multiple GPT partitions have the same name?

> The 'swap' mode prints a warning if no matching partition names
> are found.  If only one matching name of a provided pair is found, it
> renames the matching partitions to the new name.

I see a problem here...

> +	if (!strcmp(subcomm, "swap")) {
> +		if ((strlen(name1) > PART_NAME_LEN) || (strlen(name2) > PART_NAME_LEN)) {
> +			printf("Names longer than %d characters are truncated.\n", PART_NAME_LEN);
> +			return -EINVAL;
> +		}
> +		list_for_each(pos, &disk_partitions) {
> +			curr = list_entry(pos, struct disk_part, list);
> +			if (!strcmp((char *)curr->gpt_part_info.name, name1)) {
> +				strcpy((char *)curr->gpt_part_info.name, name2);
> +				changed++;
> +			}
> +			else if (!strcmp((char *)curr->gpt_part_info.name, name2)) {
> +				strcpy((char *)curr->gpt_part_info.name, name1);
> +				changed++;
> +			}
> +
> +		}
> +		if (changed == 0) {
> +			printf("No matching partition names were found.\n");
> +			return ret;
> +		}

You will never know if there really was a pair of names that was
swapped.  Just a single rename of name1->name2 _or_ of name2->name1
will make the user think everything was fine.

[Note: I'm in the process of relocating and will be offline for the
next 2..3. days.  Don't expect more comments from mee soon.
Sorry...]

Best regards,

Wolfgang Denk

-- 
DENX Software Engineering GmbH,      Managing Director: Wolfgang Denk
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Phone: (+49)-8142-66989-10 Fax: (+49)-8142-66989-80 Email: wd at denx.de
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