lib/string.c: remove duplicated function (cd514e72) · Commits · 戴 / test

lib/string.c contains two functions, strnicmp and strncasecmp, which do roughly the same thing, namely compare two strings case-insensitively up to a given bound. They have slightly different implementations, but the only important difference is that strncasecmp doesn't handle len==0 appropriately; it effectively becomes strcasecmp in that case. strnicmp correctly says that two strings are always equal in their first 0 characters. strncasecmp is the POSIX name for this functionality. So rename the non-broken function to the standard name. To minimize the impact on the rest of the kernel (and since both are exported to modules), make strnicmp a wrapper for strncasecmp. Signed-off-by:

Rasmus Villemoes <linux@rasmusvillemoes.dk> Cc: Grant Likely <grant.likely@linaro.org> Cc: Andi Kleen <ak@linux.intel.com> Cc: Dan Carpenter <dan.carpenter@oracle.com> Cc: "H. Peter Anvin" <hpa@linux.intel.com> Signed-off-by:

Andrew Morton <akpm@linux-foundation.org> Signed-off-by:

Linus Torvalds <torvalds@linux-foundation.org>

lib/string.c

+10 −17

Original line number	Diff line number	Diff line
		@@ -27,14 +27,14 @@
		#include <linux/bug.h>
		#include <linux/errno.h>

		#ifndef __HAVE_ARCH_STRNICMP
		#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;
		@@ -56,6 +56,13 @@ int strnicmp(const char s1, const char s2, size_t len)
		} while (--len);
		return (int)c1 - (int)c2;
		}
		EXPORT_SYMBOL(strncasecmp);
		#endif
		#ifndef __HAVE_ARCH_STRNICMP
		int strnicmp(const char s1, const char s2, size_t len)
		{
		return strncasecmp(s1, s2, len);
		}
		EXPORT_SYMBOL(strnicmp);
		#endif

		@@ -73,20 +80,6 @@ int strcasecmp(const char s1, const char s2)
		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

		#ifndef __HAVE_ARCH_STRCPY
		/**
		* strcpy - Copy a %NUL terminated string

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