Re: [PATCH] vbscript: Implemented Asc(try 3)

[Nikolay Sivov]

On 04.03.2015 9:19, Shuai Meng wrote:
> - switch(V_VT(arg)) {
> - case VT_NULL:
> -
>    return MAKE_VBSERROR(VBSE_ILLEGAL_NULL_USE);
> - case VT_BSTR:
> -
>    bstr = V_BSTR(arg);
> -
>    break;
> - default:
> -
>    hres = to_string(arg, &bstr);
> -
>    if(FAILED(hres))
> -
>        return hres;
> - }
> -
> - ret = bstr[0];
> - SysFreeString(bstr);
> -
> - if(ret == 0)
> -
>    return MAKE_VBSERROR(VBSE_ILLEGAL_FUNC_CALL);
> - return return_short(res, ret);

This is wrong too. You can't always free it like that, please look 
carefully at where 'bstr' comes from.

[PATCH] vbscript: Implemented Asc(try 3)

[Shuai Meng]

Thanks for commenting.

2015-03-04 15:48 GMT+08:00 Nikolay Sivov :
> On 04.03.2015 9:19, Shuai Meng wrote:
> > - switch(V_VT(arg)) {
> > - case VT_NULL:
> > -
> >    return MAKE_VBSERROR(VBSE_ILLEGAL_NULL_USE);
> > - case VT_BSTR:
> > -
> >    bstr = V_BSTR(arg);
> > -
> >    break;
> > - default:
> > -
> >    hres = to_string(arg, &bstr);
> > -
> >    if(FAILED(hres))
> > -
> >        return hres;
> > - }
> > -
> > - ret = bstr[0];
> > - SysFreeString(bstr);
> > -
> > - if(ret == 0)
> > -
> >    return MAKE_VBSERROR(VBSE_ILLEGAL_FUNC_CALL);
> > - return return_short(res, ret);
>
> This is wrong too. You can't always free it like that, please look
> carefully at where 'bstr' comes from.

Yeah, you are right, I am so anxious that  I didn't check it carefully.
'bstr' has two source, only when it comes from to_string(), it can be freed
with this way.