strlcpy.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 65 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
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* Description:  Implementation of BSD style strlcpy() and wcslcpy().
*
****************************************************************************/


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


_WCRTLINK size_t __F_NAME(strlcpy,wcslcpy)( CHAR_TYPE *dst, const CHAR_TYPE *src, size_t len )
{
    const CHAR_TYPE     *s;
    size_t              count;

    count = len;
    if( len ) {
        --len;                  // leave space for terminating null
        for( ; len; --len ) {
            if( *src == NULLCHAR ) {
                break;
            }
            *dst++ = *src++;
        }
        *dst = NULLCHAR;        // terminate 'dst'
    } else {
        ++count;                // account for not decrementing 'len'
    }

    if( !len ) {                // source string was truncated
        s = src;
        while( *s != NULLCHAR ) {
            ++s;
        }
        count += s - src;       // find out how long 'src' really is
    }
    return( count - len - 1 );  // final null doesn't count
}