windows-nt/Source/XPSP1/NT/shell/ext/ratings/common/strqss.cpp
2020-09-26 16:20:57 +08:00

117 lines
2.7 KiB
C++

/*****************************************************************/
/** Microsoft Windows for Workgroups **/
/** Copyright (C) Microsoft Corp., 1991-1992 **/
/*****************************************************************/
/*
strqss.cxx
NLS/DBCS-aware string class: QuerySubStr method
This file contains the implementation of the QuerySubStr method
for the STRING class. It is separate so that clients of STRING which
do not use this operator need not link to it.
FILE HISTORY:
beng 01/18/91 Separated from original monolithic .cxx
beng 02/07/91 Uses lmui.hxx
*/
#include "npcommon.h"
extern "C"
{
#include <netlib.h>
}
#if defined(DEBUG)
static const CHAR szFileName[] = __FILE__;
#define _FILENAME_DEFINED_ONCE szFileName
#endif
#include <npassert.h>
#include <npstring.h>
// Magic value used below
//
#define CB_ENTIRE_STRING (-1)
/*******************************************************************
NAME: NLS_STR::QuerySubStr
SYNOPSIS: Return a pointer to a new NLS_STR that contains the contents
of *this from istrStart to:
istrStart end of string or
istrStart + istrEnd
ENTRY:
EXIT:
RETURNS: Pointer to newly alloc'd NLS_STR, or NULL if error
NOTES: The private method QuerySubStr(ISTR&, CB) is the worker
method, the other two just check the parameters and
pass the data. It is private since we can't allow the
user to access the string on a byte basis
CAVEAT: Note that this method creates an NLS_STR that the client is
responsible for deleting.
HISTORY:
johnl 11/26/90 Created
beng 04/26/91 Replaced CB wth INT; broke out CB_ENTIRE_STRING
magic value
beng 07/23/91 Allow on erroneous string; simplified CheckIstr
********************************************************************/
NLS_STR * NLS_STR::QuerySubStr( const ISTR & istrStart, INT cbLen ) const
{
if (QueryError())
return NULL;
CheckIstr( istrStart );
INT cchStrLen = ::strlenf(QueryPch(istrStart) );
INT cbCopyLen = ( cbLen == CB_ENTIRE_STRING || cbLen >= cchStrLen )
? cchStrLen
: cbLen;
NLS_STR *pnlsNew = new NLS_STR( cbCopyLen + 1 );
if ( pnlsNew == NULL )
return NULL;
if ( pnlsNew->QueryError() )
{
delete pnlsNew;
return NULL;
}
::memcpyf( pnlsNew->_pchData, QueryPch(istrStart), cbCopyLen );
*(pnlsNew->_pchData + cbCopyLen) = '\0';
pnlsNew->_cchLen = cbCopyLen;
return pnlsNew;
}
NLS_STR * NLS_STR::QuerySubStr( const ISTR & istrStart ) const
{
return QuerySubStr( istrStart, CB_ENTIRE_STRING );
}
NLS_STR * NLS_STR::QuerySubStr( const ISTR & istrStart,
const ISTR & istrEnd ) const
{
CheckIstr( istrEnd );
UIASSERT( istrEnd.QueryIB() >= istrStart.QueryIB() );
return QuerySubStr( istrStart, istrEnd - istrStart );
}