Display Mirror Driver problems

>
> Hi, Nadav
>
> Issue One:
> First of all, your external DLL have reference to
> user-mode DLL (namely, kernel32.dll). Such a DLL cant be loaded
> at all. You have to check "Ignore standard libraries" in you project
> and remove link references to anything except for win32k.lib and
> possibly int64.lib, libcntpr.lib.
> The memory mapping and the other tasks that require calls to
> ntoskrnl are better performed by miniport driver.
> Miniport is not restricted in what it can do. Add 2 IOCTLs to
> it and call it from the display part.
>
> Issue Two:
> Yes, this hooking is mandatory. If you don't install this,
> the GDI will not be able to create the screen surface on your device.
> So your driver will be unloaded as being useless.
> Mandatory hooks are enumerated in Windows DDK.
>
> Issue Three:
> The mirror driver, as any other display driver, is unloaded
> when the video mode settings change and it is no longer
> required to be loaded.
> It is about Attach.ToDesktop registry value
> (CurrentControlSet\HardwareProfiles subtree, not

> one).
>
>
> ------------------------
> Unfortunately you didn't left your real e-mail address.
> So, if you want to talk more about mirror drivers, feel free to
> contact me.
>
> --------------------
> Lev Kazarkin
> Mirror drivers. Consulting and custom development.
>
>
>
> "Nadav" <Not@today.com> wrote in message
> news:eEGrUTT9DHA.3404@TK2MSFTNGP09.phx.gbl...

> > Hi,
> >
> > I am developing a display mirror drive, following is a description of
> > several issues I have encountered, any help will be appreciated.
> >
> > Issue One:
> > INTRODUCTION: I am tying to map kernel memory to user memory in a mirror
> > display driver based upon the sample given in the DDK, to achieve the
> > mapping I have created an external DLL ( Here on this DLL will be

> > as DispCmn.DLL ) that encapsulate all of the memory management functions

> > e.g. SHM_Alloc and SHM_Dealloc ), I am using EngLoadImage in combination
> > with EngFindImageProcAddress to access the methods just described
> > THE PROBLEM: EngLoadImage returns NULL although the binary DLL file is
> > actually being accessed by the kernel ( this was verified using

> sysinternals

> > FileMon ), Why is that happening? the DLL ( DispCmn.DLL ) is being

> > with wdm.lib and is dependent on NTOSKRNL.EXE and KERNEL32.DLL, may this
> > dependency impose any problems? does EngLoadImage restricts certain DLLs
> > from being loaded?
> >
> > Issue Two:
> > The Mirror sample provided with the DDK include some default hooking (

> e.g.

> > INDEX_DrvEnableSurface and INDEX_DrvDisableSurface ) Does this hooking

> > mandatory? Is it OK to disable those hooking ( for the time being )?
> > Is some hooking are mandatory how can one know what are and what are

> >
> > Issue Three:
> > The development cycle of a mirror driver is not of the shortest: one

> should

> > reboot the system each time the mirror driver is to be updated, I

> wonder...

> > Is there a way of unloading the mirror driver without rebooting the

> system?

> > this will save me a lot of the development time.
> >
> > ThanX
> > Nadav.
> > See a great COM Profiling tool I have developed at
> > http://www.ddevel.com/DrCOM.asp
> >

>
>

> following scenario as an example of what I have understand of your response:
> 1. A mirror Driver is loaded
> 2. I have set the 'Attach.ToDesktop' registry value to Zero
> 3. I am changing the video mode ( changing the resolution of the screen )
> 4. The mirror driver will be unloaded and the Driver .DLL would be able to
> be deleted/changed
> Did I get It right?