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Enhance Tech and English
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数据加载中……

char operator source code

size_t __cdecl strlen (
        const char * str
        )
{
        const char *eos = str;

        while( *eos++ ) ;

        return( eos - str - 1 );
}

int __cdecl strcmp (
        const char * src,
        const char * dst
        )
{
        int ret = 0 ;

        while( ! (ret = *(unsigned char *)src - *(unsigned char *)dst) && *dst)
                ++src, ++dst;

        if ( ret < 0 )
                ret = -1 ;
        else if ( ret > 0 )
                ret = 1 ;

        return( ret );
}

_FUNC_PROLOGUE
errno_t __cdecl _FUNC_NAME(_CHAR *_DEST, size_t _SIZE, const _CHAR *_SRC)
{
    _CHAR *p;
    size_t available;

    /* validation section */
    _VALIDATE_STRING(_DEST, _SIZE);
    _VALIDATE_POINTER_RESET_STRING(_SRC, _DEST, _SIZE);

    p = _DEST;
    available = _SIZE;
    while ((*p++ = *_SRC++) != 0 && --available > 0)
    {
    }

    if (available == 0)
    {
        _RESET_STRING(_DEST, _SIZE);
        _RETURN_BUFFER_TOO_SMALL(_DEST, _SIZE);
    }
    _FILL_STRING(_DEST, _SIZE, _SIZE - available + 1);
    _RETURN_NO_ERROR;
}

_FUNC_PROLOGUE
errno_t __cdecl _FUNC_NAME(_CHAR *_DEST, size_t _SIZE, const _CHAR *_SRC)
{
    _CHAR *p;
    size_t available;

    /* validation section */
    _VALIDATE_STRING(_DEST, _SIZE);
    _VALIDATE_POINTER_RESET_STRING(_SRC, _DEST, _SIZE);

    p = _DEST;
    available = _SIZE;
    while (available > 0 && *p != 0)
    {
        p++;
        available--;
    }

    if (available == 0)
    {
        _RESET_STRING(_DEST, _SIZE);
        _RETURN_DEST_NOT_NULL_TERMINATED(_DEST, _SIZE);
    }

    while ((*p++ = *_SRC++) != 0 && --available > 0)
    {
    }

    if (available == 0)
    {
        _RESET_STRING(_DEST, _SIZE);
        _RETURN_BUFFER_TOO_SMALL(_DEST, _SIZE);
    }
    _FILL_STRING(_DEST, _SIZE, _SIZE - available + 1);
    _RETURN_NO_ERROR;
}


posted on 2011-04-12 11:13 Mike Song 阅读(261) 评论(0)  编辑 收藏 引用


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