windows-nt/Source/XPSP1/NT/com/ole32/stg/async/cruntime.cxx
2020-09-26 16:20:57 +08:00

202 lines
4.4 KiB
C++

//+---------------------------------------------------------------------------
//
// Microsoft Windows
// Copyright (C) Microsoft Corporation, 1992 - 1996.
//
// File: cruntime.cxx
//
// Contents: Implementation of Cruntimes that we need since we
// can't use MSVCRT and WIn95 doesn't implement the lstr*W
// versions. (well, it implements them but they are just stubs)
//
//
// Functions: Laylstrcmp
// Laylstrcpy
// Laylstrcpyn
// Laylstrlen
// Laylstrcat
//
// History: 20-Jun-96 SusiA Created
//
//----------------------------------------------------------------------------
#pragma hdrstop
#include <string.h>
/***
* Laylstrcmp - compare two wchar_t strings,
* returning less than, equal to, or greater than
*
*Purpose:
* wcscmp compares two wide-character strings 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 wchar_t by wchar_t on an UNSIGNED basis, which is to
* say that Null wchar_t(0) is less than any other character.
*
*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 Laylstrcmp (
const wchar_t * src,
const wchar_t * dst
)
{
int ret = 0 ;
while( ! (ret = (int)(*src - *dst)) && *dst)
++src, ++dst;
if ( ret < 0 )
ret = -1 ;
else if ( ret > 0 )
ret = 1 ;
return( ret );
}
/***
*wchar_t *Laylstrcat(dst, src) - concatenate (append) one wchar_t string to another
*
*Purpose:
* Concatenates src onto the end of dest. Assumes enough
* space in dest.
*
*Entry:
* wchar_t *dst - wchar_t string to which "src" is to be appended
* const wchar_t *src - wchar_t string to be appended to the end of "dst"
*
*Exit:
* The address of "dst"
*
*Exceptions:
*
*******************************************************************************/
wchar_t * Laylstrcat (
wchar_t * dst,
const wchar_t * src
)
{
wchar_t * cp = dst;
while( *cp )
cp++; /* find end of dst */
while( *cp++ = *src++ ) ; /* Copy src to end of dst */
return( dst ); /* return dst */
}
/***
*wchar_t *Laylstrcpy(dst, src) - copy one wchar_t string over another
*
*Purpose:
* Copies the wchar_t string src into the spot specified by
* dest; assumes enough room.
*
*Entry:
* wchar_t * dst - wchar_t string over which "src" is to be copied
* const wchar_t * src - wchar_t string to be copied over "dst"
*
*Exit:
* The address of "dst"
*
*Exceptions:
*******************************************************************************/
wchar_t * Laylstrcpy(wchar_t * dst, const wchar_t * src)
{
wchar_t * cp = dst;
while( *cp++ = *src++ )
; /* Copy src over dst */
return( dst );
}
/***
*wchar_t *Laylstrcpyn(dest, source, count) - copy at most n wide characters
*
*Purpose:
* Copies count characters from the source string to the
* destination. If count is less than the length of source,
* NO NULL CHARACTER is put onto the end of the copied string.
* If count is greater than the length of sources, dest is padded
* with null characters to length count (wide-characters).
*
*
*Entry:
* wchar_t *dest - pointer to destination
* wchar_t *source - source string for copy
* size_t count - max number of characters to copy
*
*Exit:
* returns dest
*
*Exceptions:
*
*******************************************************************************/
wchar_t * Laylstrcpyn (
wchar_t * dest,
const wchar_t * source,
size_t count
)
{
wchar_t *start = dest;
while (count && (*dest++ = *source++)) /* copy string */
count--;
if (count) /* pad out with zeroes */
while (--count)
*dest++ = L'\0';
return(start);
}
/***
*Laylstrlen - return the length of a null-terminated wide-character string
*
*Purpose:
* Finds the length in wchar_t's of the given string, not including
* the final null wchar_t (wide-characters).
*
*Entry:
* const wchar_t * wcs - string whose length is to be computed
*
*Exit:
* length of the string "wcs", exclusive of the final null wchar_t
*
*Exceptions:
*
*******************************************************************************/
size_t Laylstrlen (
const wchar_t * wcs
)
{
const wchar_t *eos = wcs;
while( *eos++ ) ;
return( (size_t)(eos - wcs - 1) );
}