Re: [PATCH 1/7] lib/string: add strnchrnul()

[Andy Shevchenko]

On Tue, Apr 30, 2019 at 06:06:30PM -0700, Yury Norov wrote:
> New function works like strchrnul() with a length limited strings.
> 

Reviewed-by: Andy Shevchenko <andriy.shevchenko@xxxxxxxxxxxxxxx>

> Signed-off-by: Yury Norov <ynorov@xxxxxxxxxxx>
> ---
>  include/linux/string.h |  1 +
>  lib/string.c           | 17 +++++++++++++++++
>  2 files changed, 18 insertions(+)
> 
> diff --git a/include/linux/string.h b/include/linux/string.h
> index 4deb11f7976b..ae934d6c50bf 100644
> --- a/include/linux/string.h
> +++ b/include/linux/string.h
> @@ -62,6 +62,7 @@ extern char * strchr(const char *,int);
>  #ifndef __HAVE_ARCH_STRCHRNUL
>  extern char * strchrnul(const char *,int);
>  #endif
> +extern char * strnchrnul(const char *, size_t, int);
>  #ifndef __HAVE_ARCH_STRNCHR
>  extern char * strnchr(const char *, size_t, int);
>  #endif
> diff --git a/lib/string.c b/lib/string.c
> index 6016eb3ac73d..eee521ad1f40 100644
> --- a/lib/string.c
> +++ b/lib/string.c
> @@ -429,6 +429,23 @@ char *strchrnul(const char *s, int c)
>  EXPORT_SYMBOL(strchrnul);
>  #endif
>  
> +/**
> + * strnchrnul - Find and return a character in a length limited string,
> + * or end of string
> + * @s: The string to be searched
> + * @count: The number of characters to be searched
> + * @c: The character to search for
> + *
> + * Returns pointer to the first occurrence of 'c' in s. If c is not found,
> + * then return a pointer to the last character of the string.
> + */
> +char *strnchrnul(const char *s, size_t count, int c)
> +{
> +	while (count-- && *s && *s != (char)c)
> +		s++;
> +	return (char *)s;
> +}
> +
>  #ifndef __HAVE_ARCH_STRRCHR
>  /**
>   * strrchr - Find the last occurrence of a character in a string
> -- 
> 2.17.1
> 

-- 
With Best Regards,
Andy Shevchenko