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

137 lines
3.9 KiB
C

/***
*strnicmp.c - compare n chars of strings, ignoring case
*
* Copyright (c) 1985-2001, Microsoft Corporation. All rights reserved.
*
*Purpose:
* defines _strnicmp() - Compares at most n characters of two strings,
* without regard to case.
*
*Revision History:
* 02-27-90 GJF Fixed calling type, #include <cruntime.h>, fixed
* copyright.
* 10-02-90 GJF New-style function declarator.
* 01-18-91 GJF ANSI naming.
* 10-11-91 GJF Bug fix! Comparison of final bytes must use unsigned
* chars.
* 09-03-93 GJF Replaced _CALLTYPE1 with __cdecl.
* 09-21-93 CFW Avoid cast bug.
* 01-13-94 CFW Fix Comments.
* 10-19-94 GJF Sped up C locale. Also, made multi-thread safe.
* 12-29-94 CFW Merge non-Win32.
* 09-26-95 GJF New locking macro, and scheme, for functions which
* reference the locale.
* 11-15-95 BWT Fix _NTSUBSET_
* 08-11-98 GJF Revised multithread support based on threadlocinfo
* struct.
* 09-08-98 GJF Split out ASCII-only version.
* 05-17-99 PML Remove all Macintosh support.
* 26-01-00 GB Modified strnicmp for performance.
* 09-03-00 GB Moved the performance code to toupper and tolower.
* restored the original file.
*
*******************************************************************************/
#include <cruntime.h>
#include <string.h>
#include <mtdll.h>
#include <ctype.h>
#include <setlocal.h>
#include <locale.h>
/***
*int _strnicmp(first, last, count) - compares count char 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.
*
*Entry:
* char *first, *last - strings to compare
* size_t count - maximum number of characters to compare
*
*Exit:
* returns <0 if first < last
* returns 0 if first == last
* returns >0 if first > last
*
*Exceptions:
*
*******************************************************************************/
int __cdecl _strnicmp (
const char * dst,
const char * src,
size_t count
)
{
int f,l;
#ifdef _MT
pthreadlocinfo ptloci = _getptd()->ptlocinfo;
if ( ptloci != __ptlocinfo )
ptloci = __updatetlocinfo();
#endif
if ( count )
{
#if !defined(_NTSUBSET_)
#ifdef _MT
if ( ptloci->lc_handle[LC_CTYPE] == _CLOCALEHANDLE ) {
#else
if ( __lc_handle[LC_CTYPE] == _CLOCALEHANDLE ) {
#endif
#endif /* !_NTSUBSET_ */
return __ascii_strnicmp(dst, src, count);
#if !defined(_NTSUBSET_)
}
else {
do {
#ifdef _MT
f = __tolower_mt( ptloci, (unsigned char)(*(dst++)) );
l = __tolower_mt( ptloci, (unsigned char)(*(src++)) );
#else
f = tolower( (unsigned char)(*(dst++)) );
l = tolower( (unsigned char)(*(src++)) );
#endif
} while (--count && f && (f == l) );
}
#endif /* !_NTSUBSET_ */
return( f - l );
}
return( 0 );
}
#ifndef _M_IX86
int __cdecl __ascii_strnicmp (
const char * first,
const char * last,
size_t count
)
{
int f, l;
do {
if ( ((f = (unsigned char)(*(first++))) >= 'A') &&
(f <= 'Z') )
f -= 'A' - 'a';
if ( ((l = (unsigned char)(*(last++))) >= 'A') &&
(l <= 'Z') )
l -= 'A' - 'a';
} while ( --count && f && (f == l) );
return ( f - l );
}
#endif