windows-nt/Source/XPSP1/NT/base/crts/crtw32/string/wcsnicmp.c
2020-09-26 16:20:57 +08:00

113 lines
3.4 KiB
C

/***
*wcsnicmp.c - compare n chars of wide-character strings, ignoring case
*
* Copyright (c) 1985-2001, Microsoft Corporation. All rights reserved.
*
*Purpose:
* defines _wcsnicmp() - Compares at most n characters of two wchar_t
* strings, without regard to case.
*
*Revision History:
* 09-09-91 ETC Created from strnicmp.c and wcsicmp.c.
* 12-09-91 ETC Use C for neutral locale.
* 04-07-92 KRS Updated and ripped out _INTL switches.
* 04-06-93 SKS Replace _CRTAPI* with __cdecl
* 04-14-93 CFW Remove locale-sensitive portion.
* 09-07-93 GJF Fixed bug introduced on 4-14 (return value not was
* not well-defined if count == 0).
* 02-07-94 CFW POSIXify.
* 09-06-94 CFW Remove _INTL switch.
* 10-25-94 GJF Now works in non-C locales.
* 09-26-95 GJF New locking macro, and scheme, for functions which
* reference the locale.
* 10-11-95 BWT Fix NTSUBSET
* 08-27-98 GJF Revised multithread support based on threadlocinfo
* struct.
*
*******************************************************************************/
#ifndef _POSIX_
#include <cruntime.h>
#include <string.h>
#include <ctype.h>
#include <locale.h>
#include <setlocal.h>
#include <mtdll.h>
/***
*int _wcsnicmp(first, last, count) - compares count wchar_t of strings,
* ignore case
*
*Purpose:
* Compare the two strings for lexical order. Stops the comparison
* when the following occurs: (1) strings differ, (2) the end of the
* strings is reached, or (3) count characters have been compared.
* For the purposes of the comparison, upper case characters are
* converted to lower case (wide-characters).
*
*Entry:
* wchar_t *first, *last - strings to compare
* size_t count - maximum number of characters to compare
*
*Exit:
* -1 if first < last
* 0 if first == last
* 1 if first > last
* This range of return values may differ from other *cmp/*coll functions.
*
*Exceptions:
*
*******************************************************************************/
int __cdecl _wcsnicmp (
const wchar_t * first,
const wchar_t * last,
size_t count
)
{
wchar_t f,l;
int result = 0;
#ifdef _MT
pthreadlocinfo ptloci = _getptd()->ptlocinfo;
if ( ptloci != __ptlocinfo )
ptloci = __updatetlocinfo();
#endif
if ( count ) {
#ifndef _NTSUBSET_
#ifdef _MT
if ( ptloci->lc_handle[LC_CTYPE] == _CLOCALEHANDLE ) {
#else
if ( __lc_handle[LC_CTYPE] == _CLOCALEHANDLE ) {
#endif
#endif /* _NTSUBSET_ */
do {
f = __ascii_towlower(*first);
l = __ascii_towlower(*last);
first++;
last++;
} while ( (--count) && f && (f == l) );
#ifndef _NTSUBSET_
}
else {
do {
#ifdef _MT
f = __towlower_mt( ptloci, (unsigned short)(*(first++)) );
l = __towlower_mt( ptloci, (unsigned short)(*(last++)) );
#else
f = towlower( (unsigned short)(*(first++)) );
l = towlower( (unsigned short)(*(last++)) );
#endif
} while ( (--count) && f && (f == l) );
}
#endif /* _NTSUBSET_ */
result = (int)(f - l);
}
return result;
}
#endif /* _POSIX_ */