[PATCH v2 1/2] string: add mem_is_zero() helper to check if memory area is all zeros

[Andy Shevchenko]

On Wed, Aug 14, 2024 at 1:00 PM Jani Nikula <jani.nikula at intel.com> wrote:
>
> Almost two thirds of the memchr_inv() usages check if the memory area is
> all zeros, with no interest in where in the buffer the first non-zero
> byte is located. Checking for !memchr_inv(s, 0, n) is also not very
> intuitive or discoverable. Add an explicit mem_is_zero() helper for this
> use case.
>
> Signed-off-by: Jani Nikula <jani.nikula at intel.com>

...

>  void *memchr_inv(const void *s, int c, size_t n);

I would group them here, or move the above.

>  char *strreplace(char *str, char old, char new);
>
> +/**
> + * mem_is_zero - Check if an area of memory is all 0's.
> + * @s: The memory area
> + * @n: The size of the area
> + *
> + * Return: True if the area of memory is all 0's.
> + */
> +static inline bool mem_is_zero(const void *s, size_t n)
> +{
> +       return !memchr_inv(s, 0, n);
> +}

Reviewed-by: Andy Shevchenko <andy at kernel.org>

-- 
With Best Regards,
Andy Shevchenko