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/* Copyright (c) 2009 Corinna Vinschen <corinna@vinschen.de> */
/*
FUNCTION
<<wcsncasecmp>>---case-insensitive wide character string compare
INDEX
wcsncasecmp
SYNOPSIS
#include <wchar.h>
int wcsncasecmp(const wchar_t *<[a]>, const wchar_t * <[b]>, size_t <[length]>);
DESCRIPTION
<<wcsncasecmp>> compares up to <[length]> wide characters
from the string at <[a]> to the string at <[b]> in a
case-insensitive manner.
RETURNS
If <<*<[a]>>> sorts lexicographically after <<*<[b]>>> (after
both are converted to uppercase), <<wcsncasecmp>> returns a
number greater than zero. If the two strings are equivalent,
<<wcsncasecmp>> returns zero. If <<*<[a]>>> sorts
lexicographically before <<*<[b]>>>, <<wcsncasecmp>> returns a
number less than zero.
PORTABILITY
POSIX-1.2008
<<wcsncasecmp>> requires no supporting OS subroutines. It uses
tolower() from elsewhere in this library.
QUICKREF
wcsncasecmp
*/
#define _DEFAULT_SOURCE
#include <wchar.h>
#include <wctype.h>
int
wcsncasecmp(const wchar_t *s1, const wchar_t *s2, size_t n)
{
int d = 0;
for (; n != 0; n--) {
const int c1 = towlower(*s1++);
const int c2 = towlower(*s2++);
if (((d = c1 - c2) != 0) || (c2 == '\0'))
break;
}
return d;
}