windows-nt/Source/XPSP1/NT/com/ole32/stg/wclib/wcsicmp.c

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2020-09-26 03:20:57 -05:00
/***
*wcsicmp.c - compares two wide character strings with case insensitivity
*
* Copyright (c) 1985-1988, Microsoft Corporation. All rights reserved.
*
*Purpose:
* defines wcsicmp() - compares two wide character strings for lexical
* order with case insensitivity.
*
*Revision History:
* 11-Mar-92 CarlH Created.
*
*******************************************************************************/
#include <stdlib.h>
/***
*wchar_t wcUp(wc) - upper case wide character
*
*Notes:
* This was copied from AlexT's version of wcsnicmp.c from the Win4
* common project.
*/
static wchar_t wcUp(wchar_t wc)
{
if ('a' <= wc && wc <= 'z')
wc += (wchar_t)('A' - 'a');
return(wc);
}
/***
*wcsicmp - compare two wide character strings with case insensitivity,
* returning less than, equal to, or greater than
*
*Purpose:
* WCSICMP compares two wide character strings with case insensitivity
* and returns an integer to indicate whether the first is less than
* the second, the two are equal, or whether the first is greater than
* the second.
*
* Comparison is done byte by byte on an UNSIGNED basis with lower to
* upper case mapping by wcUp. Null (0) is less than any other
* character (1-0xffff).
*
*Entry:
* const wchar_t * src - string for left-hand side of comparison
* const wchar_t * dst - string for right-hand side of comparison
*
*Exit:
* returns -1 if src < dst
* returns 0 if src == dst
* returns +1 if src > dst
*
*Exceptions:
*
*******************************************************************************/
int __cdecl wcsicmp(const wchar_t * src, const wchar_t * dst)
{
int ret = 0 ;
while( ! (ret = wcUp(*src) - wcUp(*dst)) && *dst)
++src, ++dst;
if ( ret < 0 )
ret = -1 ;
else if ( ret > 0 )
ret = 1 ;
return ret;
}