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

[Ardelean, Alexandru]

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 at analog.com>
> ---
>  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;
>  	}