Re: [ros-dev] Problem with out current NtGdiExtGetObjectW implementation

[Timo Kreuzer]

That's what we are using.
And in fact it seems that Windows supports a maximum of 16 styles for 
extpens and that will fit in our union.
Yay! ;-)

Jerry schrieb:
> What about a stack buffer that can hold most of all cases?
>
> On 4/30/07, Alex Ionescu [e-mail] wrote:
> > Hi,
> >
> > The NtGdi function in NT, according to my tests, only copies whatever can
> > fit in the union. I suggest we keep this behaviour.
> >
> > Best regards,
> > Alex Ionescu
> >
> > -----Original Message-----
> > From: [e-mail] [mailto:[e-mail]] On
> > Behalf Of Timo Kreuzer
> > Sent: April-30-07 9:38 AM
> > To: [e-mail]
> > Subject: [ros-dev] Problem with out current NtGdiExtGetObjectW
> > implementation
> >
> > Hi,
> >
> > although I like the way NtGdiExtGetObjectW is using the union, we will
> > get a problem with it.
> > We don't know how many styles an extpen has, so we cannot statically
> > allocate a kmode buffer that is big enough.
> >
> > I can currently think of 3 possible solutions:
> > Add a big additional hack for GDI_OBJECT_TYPE_EXTPEN in
> >
> > NtGdiExtGetObjectW, that will copy the styles, wich seems to be a bad idea.
> > Use the old method of first calling IntGdiExtGetObjectW to get the
> >
> > needed buffer size then allocate a kernelmode buffer then call
> > IntGdiExtGetObjectW again to tranfer the data then copy to usermode.
> > This is slower and needs extra memory.
> > Move the copying to usermode to the XXX_GetObject functions. This
> >
> > would remove the need for an extra kernelmode buffer and we wouldn't
> > really need IntGdiExtGetObjectW anymore. But it doesn't match the rest
> > of our call chain design.
> >
> > Comments appreciated.
> > Timo
> >
> > Ros-dev mailing list
> > [e-mail]
> > http://www.reactos.org/mailman/listinfo/ros-dev
> >
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