Re: [PATCH 01/16] lib: fix match_string() helper on -1 array size

From: "Ardelean, Alexandru" <alexandru.Ardelean-OyLXuOCK7orQT0dZR+AlfA@public.gmane.org>
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Subject: Re: [PATCH 01/16] lib: fix match_string() helper on -1 array size
Date: Wed, 8 May 2019 11:31:15 +0000	[thread overview]
Message-ID: <c8cfa5dbdfc0b0665d1b48f37ba57c3ec1233197.camel__29211.3176825055$1557315348$gmane$org@analog.com> (raw)
In-Reply-To: <20190508112842.11654-2-alexandru.ardelean-OyLXuOCK7orQT0dZR+AlfA@public.gmane.org>

On Wed, 2019-05-08 at 14:28 +0300, Alexandru Ardelean wrote:
> The documentation the `_match_string()` helper mentions that `n`
> should be:
>  * @n: number of strings in the array or -1 for NULL terminated arrays
> 
> The behavior of the function is different, in the sense that it exits on
> the first NULL element in the array, regardless of whether `n` is -1 or a
> positive number.
> 
> This patch changes the behavior, to exit the loop when a NULL element is
> found and n == -1. Essentially, this aligns the behavior with the
> doc-string.
> 
> There are currently many users of `match_string()`, and so, in order to
> go
> through them, the next patches in the series will focus on doing some
> cosmetic changes, which are aimed at grouping the users of
> `match_string()`.
> 

This is the duplicate & should be dropped.
Sorry for this.

> Signed-off-by: Alexandru Ardelean <alexandru.ardelean-OyLXuOCK7orQT0dZR+AlfA@public.gmane.org>
> ---
>  lib/string.c | 5 ++++-
>  1 file changed, 4 insertions(+), 1 deletion(-)
> 
> diff --git a/lib/string.c b/lib/string.c
> index 3ab861c1a857..76edb7bf76cb 100644
> --- a/lib/string.c
> +++ b/lib/string.c
> @@ -648,8 +648,11 @@ int match_string(const char * const *array, size_t
> n, const char *string)
>  
>  	for (index = 0; index < n; index++) {
>  		item = array[index];
> -		if (!item)
> +		if (!item) {
> +			if (n != (size_t)-1)
> +				continue;
>  			break;
> +		}
>  		if (!strcmp(item, string))
>  			return index;
>  	}