umemmov.c

来自「开放源码的编译器open watcom 1.6.0版的源代码」· C语言 代码 · 共 61 行

/****************************************************************************
*
*                            Open Watcom Project
*
*    Portions Copyright (c) 1983-2002 Sybase, Inc. All Rights Reserved.
*
*  ========================================================================
*
*    This file contains Original Code and/or Modifications of Original
*    Code as defined in and that are subject to the Sybase Open Watcom
*    Public License version 1.0 (the 'License'). You may not use this file
*    except in compliance with the License. BY USING THIS FILE YOU AGREE TO
*    ALL TERMS AND CONDITIONS OF THE LICENSE. A copy of the License is
*    provided with the Original Code and Modifications, and is also
*    available at www.sybase.com/developer/opensource.
*
*    The Original Code and all software distributed under the License are
*    distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
*    EXPRESS OR IMPLIED, AND SYBASE AND ALL CONTRIBUTORS HEREBY DISCLAIM
*    ALL SUCH WARRANTIES, INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF
*    MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR
*    NON-INFRINGEMENT. Please see the License for the specific language
*    governing rights and limitations under the License.
*
*  ========================================================================
*
* Description:  Implementation of wmemmove().
*
****************************************************************************/


#include "variety.h"
#include "widechar.h"
#include <wchar.h>


_WCRTLINK wchar_t *wmemmove( wchar_t *toStart, const wchar_t *fromStart, size_t len )
{
    const wchar_t   *from = fromStart;
    wchar_t         *to = toStart;

    if( from == to ) {
        return( to );
    }
    if( (from < to) && (from + len > to) ) {    /* if buffers are overlapped */
        to += len;
        from += len;
        while( len != 0 ) {
            *--to = *--from;
            --len;
        }
    } else {
        while( len != 0 ) {
            *to++ = *from++;
            --len;
        }
    }

    return( toStart );
}