Re: [PATCH] lib: string: remove duplicated function

[Sascha Hauer <s.hauer@pengutronix.de>]

On Thu, Mar 16, 2023 at 10:36:50AM +0300, Denis Orlov wrote:
> We have two functions that are doing the same thing: 'strncasecmp' and
> 'strnicmp'. The only difference between them is that the latter is
> correctly handling the len argument of 0. So rename it into the former
> one ('strncasecmp', as it is the POSIX name for this function), deleting
> the other implementation. As no one is actually using 'strnicmp', no
> other code requires any fixes.
> 
> This change is effectively forwarded from the Linux commits
> 'lib/string.c: remove duplicated function'
> (hash cd514e727b18ff4d189b8e268db13729a4175091) and
> 'lib/string.c: remove strnicmp()'
> (hash af3cd13501eb04ca61d017ff4406f1cbffafdc04).
> 
> Signed-off-by: Denis Orlov <denorl2009@gmail.com>
> ---
>  include/linux/string.h |  3 ---
>  lib/string.c           | 48 +++++++++++++++---------------------------
>  2 files changed, 17 insertions(+), 34 deletions(-)

Applied, thanks

Sascha

> 
> diff --git a/include/linux/string.h b/include/linux/string.h
> index 0c79d3e5cf..cd81ab1396 100644
> --- a/include/linux/string.h
> +++ b/include/linux/string.h
> @@ -58,9 +58,6 @@ extern int strcmp(const char *,const char *);
>  #ifndef __HAVE_ARCH_STRNCMP
>  extern int strncmp(const char *,const char *,__kernel_size_t);
>  #endif
> -#ifndef __HAVE_ARCH_STRNICMP
> -extern int strnicmp(const char *, const char *, __kernel_size_t);
> -#endif
>  #ifndef __HAVE_ARCH_STRCASECMP
>  extern int strcasecmp(const char *s1, const char *s2);
>  #endif
> diff --git a/lib/string.c b/lib/string.c
> index 005f4532bb..8ea68044cc 100644
> --- a/lib/string.c
> +++ b/lib/string.c
> @@ -24,14 +24,28 @@
>  #include <linux/ctype.h>
>  #include <malloc.h>
>  
> -#ifndef __HAVE_ARCH_STRNICMP
> +#ifndef __HAVE_ARCH_STRCASECMP
> +int strcasecmp(const char *s1, const char *s2)
> +{
> +	int c1, c2;
> +
> +	do {
> +		c1 = tolower(*s1++);
> +		c2 = tolower(*s2++);
> +	} while (c1 == c2 && c1 != 0);
> +	return c1 - c2;
> +}
> +EXPORT_SYMBOL(strcasecmp);
> +#endif
> +
> +#ifndef __HAVE_ARCH_STRNCASECMP
>  /**
> - * strnicmp - Case insensitive, length-limited string comparison
> + * strncasecmp - Case insensitive, length-limited string comparison
>   * @s1: One string
>   * @s2: The other string
>   * @len: the maximum number of characters to compare
>   */
> -int strnicmp(const char *s1, const char *s2, size_t len)
> +int strncasecmp(const char *s1, const char *s2, size_t len)
>  {
>  	/* Yes, Virginia, it had better be unsigned */
>  	unsigned char c1, c2;
> @@ -53,34 +67,6 @@ int strnicmp(const char *s1, const char *s2, size_t len)
>  	} while (--len);
>  	return (int)c1 - (int)c2;
>  }
> -EXPORT_SYMBOL(strnicmp);
> -#endif
> -
> -#ifndef __HAVE_ARCH_STRCASECMP
> -int strcasecmp(const char *s1, const char *s2)
> -{
> -	int c1, c2;
> -
> -	do {
> -		c1 = tolower(*s1++);
> -		c2 = tolower(*s2++);
> -	} while (c1 == c2 && c1 != 0);
> -	return c1 - c2;
> -}
> -EXPORT_SYMBOL(strcasecmp);
> -#endif
> -
> -#ifndef __HAVE_ARCH_STRNCASECMP
> -int strncasecmp(const char *s1, const char *s2, size_t n)
> -{
> -	int c1, c2;
> -
> -	do {
> -		c1 = tolower(*s1++);
> -		c2 = tolower(*s2++);
> -	} while ((--n > 0) && c1 == c2 && c1 != 0);
> -	return c1 - c2;
> -}
>  EXPORT_SYMBOL(strncasecmp);
>  #endif
>  
> -- 
> 2.30.2
> 
> 

-- 
Pengutronix e.K.                           |                             |
Steuerwalder Str. 21                       | http://www.pengutronix.de/  |
31137 Hildesheim, Germany                  | Phone: +49-5121-206917-0    |
Amtsgericht Hildesheim, HRA 2686           | Fax:   +49-5121-206917-5555 |