Re: oleaut32: Copying a NULL BSTR should result in an empty BSTR in VariantCopy

[Robert Shearman]

qingdoa daoo wrote:
> Hi,
>
> This patch should fix Bug 4141
>
> Changelog:
> Copying a NULL BSTR should result in an empty BSTR in VariantCopy
>
> ------------------------------------------------------------------------
>
> --- dlls/oleaut32/variant.c.cvs	2006-07-05 17:23:04.000000000 +0800
> +++ dlls/oleaut32/variant.c	2006-07-05 17:31:53.000000000 +0800
> @@ -719,13 +719,16 @@ HRESULT WINAPI VariantCopy(VARIANTARG* p
>       else if (V_VT(pvargSrc) == VT_BSTR)
>       {
>         if (V_BSTR(pvargSrc))
> -        {
>           V_BSTR(pvargDest) = SysAllocStringByteLen((char*)V_BSTR(pvargSrc), SysStringByteLen(V_BSTR(pvargSrc)));
> -          if (!V_BSTR(pvargDest))
> -	  {
> -	    TRACE("!V_BSTR(pvargDest), SysAllocStringByteLen() failed to allocate %d bytes\n", SysStringByteLen(V_BSTR(pvargSrc)));
> -            hres = E_OUTOFMEMORY;
> -	  }
> +        else
> +        {
> +          OLECHAR c = 0;
> +          V_BSTR(pvargDest) = SysAllocString(&c);
> +        }
> +        if (!V_BSTR(pvargDest))
> +        {
> +          TRACE("Allocation failed for destination BSTR\n");
> +          hres = E_OUTOFMEMORY;
>         }
>       }
>       else if (V_VT(pvargSrc) == VT_RECORD)

I think you could get the same result by just removing the "if 
(V_BSTR(pvargSrc)" check. This should result in simpler code.

-- 
Rob Shearman