Mixed mode ActiveX DLL

[NPotnis]

Hi ,

I am trying to host .Net UserControls in a MFC Application. The MFC
Application is an ActiveX DLL. I inserted required managed code inside the
MFC application, making it a mixed mode DLL.
I am following the KB article for mixed mode DLL's
http://support.microsoft.com/?id=814472
I linked the DLL with /noentry option. Also I added and exported the
DllEnsureInit and DllForceTerm methods in my DLL which call
__crt_dll_initi alize() and __crt_dll_termi nate() respectively. So far so good.

Now in the consumer application, this ActiveX control is created dynamically
by the COleControlSite ::CreateControl method. I understand that I would need
to invoke my init/term DLL functions manually after loading the the mixed
mode DLL.
How do I go about invoking these functions here ? The KB article
demonstrates use of GetModuleHandle and GetProcAddress which I believe may
not be usefule

Is this feasible ? Kindly advise.
Any inputs would be highly appreciated.
Thanks in advance,
Niranjan

[Marcus Heege]

The intention of the delayed CRT initialization is to avoid a deadlock,
which can happen if managed code is executed during DLLMain. After DLLMain
is called, your client will likely call DllGetClassObje ct to instantiate the
COM object. Unless some other code is called before DllGetClassObje ct, I
would initialize the CRT in your DllGetClassObje ct implementation.

Marcus

"NPotnis" <NP*****@discus sions.microsoft .comwrote in message
news:5C******** *************** ***********@mic rosoft.com...

Hi ,

I am trying to host .Net UserControls in a MFC Application. The MFC
Application is an ActiveX DLL. I inserted required managed code inside
the
MFC application, making it a mixed mode DLL.
I am following the KB article for mixed mode DLL's
http://support.microsoft.com/?id=814472
I linked the DLL with /noentry option. Also I added and exported the
DllEnsureInit and DllForceTerm methods in my DLL which call
__crt_dll_initi alize() and __crt_dll_termi nate() respectively. So far so
good.

Now in the consumer application, this ActiveX control is created
dynamically
by the COleControlSite ::CreateControl method. I understand that I would
need
to invoke my init/term DLL functions manually after loading the the mixed
mode DLL.
How do I go about invoking these functions here ? The KB article
demonstrates use of GetModuleHandle and GetProcAddress which I believe may
not be usefule

Is this feasible ? Kindly advise.
Any inputs would be highly appreciated.
Thanks in advance,
Niranjan

[NPotnis]

Hi Marcus,
Thanks for your reply.

I tried to investigate the current scenario without the CRT initialization
code in place. The client is calling the DllGetClassObje ct in library file
oleexp.cpp. I do not have my implementation of DllGetClassObje ct. If I try
to implement my DllGetClassObje ct in the DLL code, the linker gives error
saying DllGetClassObje ct is already linked from oleexp.cpp.

What would I need to do to provide and use my implementation of
DllGetClassObje ct ?

The call to DllGetClassObje ct is currently failing with
CLASS_E_CLASSNO TAVAILABLE (ClassFactory cannot supply
requested class ), which I would assume is because of lack of CRT
initialization.

Thanks,
Niranjan

"Marcus Heege" wrote:

The intention of the delayed CRT initialization is to avoid a deadlock,
which can happen if managed code is executed during DLLMain. After DLLMain
is called, your client will likely call DllGetClassObje ct to instantiate the
COM object. Unless some other code is called before DllGetClassObje ct, I
would initialize the CRT in your DllGetClassObje ct implementation.

Marcus

"NPotnis" <NP*****@discus sions.microsoft .comwrote in message
news:5C******** *************** ***********@mic rosoft.com...

Hi ,

I am trying to host .Net UserControls in a MFC Application. The MFC
Application is an ActiveX DLL. I inserted required managed code inside
the
MFC application, making it a mixed mode DLL.
I am following the KB article for mixed mode DLL's
http://support.microsoft.com/?id=814472
I linked the DLL with /noentry option. Also I added and exported the
DllEnsureInit and DllForceTerm methods in my DLL which call
__crt_dll_initi alize() and __crt_dll_termi nate() respectively. So far so
good.

Now in the consumer application, this ActiveX control is created
dynamically
by the COleControlSite ::CreateControl method. I understand that I would
need
to invoke my init/term DLL functions manually after loading the the mixed
mode DLL.
How do I go about invoking these functions here ? The KB article
demonstrates use of GetModuleHandle and GetProcAddress which I believe may
not be usefule

Is this feasible ? Kindly advise.
Any inputs would be highly appreciated.
Thanks in advance,
Niranjan

[Marcus Heege]

I my answer, I assumed that you used ATL instead of MFC. In this case, it
would have been easy to overwrite DllGetClassObje ct.With MFC, the story is
more difficult. I currently don't have VS2003 installed on my machine.
Therefore, I can't easily try it before I suggest something. But you may try
the following:

Modify the .def file so that

EXPORTS
DllCanUnloadNow PRIVATE
DllGetClassObje ct = MyDllGetClassOb ject PRIVATE
DllRegisterServ er PRIVATE
DllUnregisterSe rver PRIVATE

Implement MyDllGetClassOb ject so that you initialize the CRT if this has not
happened before. Once you ensured that the CRT is initialized, call
DllGetClassObje ct.

Please let us know if this works

Marcus
"NPotnis" <NP*****@discus sions.microsoft .comwrote in message
news:3E******** *************** ***********@mic rosoft.com...

Hi Marcus,
Thanks for your reply.

I tried to investigate the current scenario without the CRT initialization
code in place. The client is calling the DllGetClassObje ct in library file
oleexp.cpp. I do not have my implementation of DllGetClassObje ct. If I
try
to implement my DllGetClassObje ct in the DLL code, the linker gives error
saying DllGetClassObje ct is already linked from oleexp.cpp.

What would I need to do to provide and use my implementation of
DllGetClassObje ct ?

The call to DllGetClassObje ct is currently failing with
CLASS_E_CLASSNO TAVAILABLE (ClassFactory cannot supply
requested class ), which I would assume is because of lack of CRT
initialization.

Thanks,
Niranjan

"Marcus Heege" wrote:

>The intention of the delayed CRT initialization is to avoid a deadlock,
which can happen if managed code is executed during DLLMain. After
DLLMain
is called, your client will likely call DllGetClassObje ct to instantiate
the
COM object. Unless some other code is called before DllGetClassObje ct, I
would initialize the CRT in your DllGetClassObje ct implementation.

Marcus

"NPotnis" <NP*****@discus sions.microsoft .comwrote in message
news:5C******* *************** ************@mi crosoft.com...

Hi ,

I am trying to host .Net UserControls in a MFC Application. The MFC
Application is an ActiveX DLL. I inserted required managed code inside
the
MFC application, making it a mixed mode DLL.
I am following the KB article for mixed mode DLL's
http://support.microsoft.com/?id=814472
I linked the DLL with /noentry option. Also I added and exported the
DllEnsureInit and DllForceTerm methods in my DLL which call
__crt_dll_initi alize() and __crt_dll_termi nate() respectively. So far
so
good.

Now in the consumer application, this ActiveX control is created
dynamically
by the COleControlSite ::CreateControl method. I understand that I would
need
to invoke my init/term DLL functions manually after loading the the
mixed
mode DLL.
How do I go about invoking these functions here ? The KB article
demonstrates use of GetModuleHandle and GetProcAddress which I believe
may
not be usefule

Is this feasible ? Kindly advise.
Any inputs would be highly appreciated.
Thanks in advance,
Niranjan

[NPotnis]

Hi Marcus,
Actually I did it in a different way and it works. Though it has taken me by
a bit of surprise. Heres the story - If I provide implementation of only
DllGetClassObje ct
the linker complains of multiply defined symbols. Same is the case if I just
implement DllCanUnloadNow . However if I implement both, the linker is happy
and moreover my implementations get used. I implemented both
DllGetClassObje ct and DllCanUnloadNow and put the CRT initilization in
DllGetClassObje ct. It worked.
What do you think have made this happen ? (is it an intelligent compiler /
linker ?)

Thanks,
Niranjan

"Marcus Heege" wrote:

I my answer, I assumed that you used ATL instead of MFC. In this case, it
would have been easy to overwrite DllGetClassObje ct.With MFC, the story is
more difficult. I currently don't have VS2003 installed on my machine.
Therefore, I can't easily try it before I suggest something. But you may try
the following:

Modify the .def file so that

EXPORTS
DllCanUnloadNow PRIVATE
DllGetClassObje ct = MyDllGetClassOb ject PRIVATE
DllRegisterServ er PRIVATE
DllUnregisterSe rver PRIVATE

Implement MyDllGetClassOb ject so that you initialize the CRT if this has not
happened before. Once you ensured that the CRT is initialized, call
DllGetClassObje ct.

Please let us know if this works

Marcus
"NPotnis" <NP*****@discus sions.microsoft .comwrote in message
news:3E******** *************** ***********@mic rosoft.com...

Hi Marcus,
Thanks for your reply.

I tried to investigate the current scenario without the CRT initialization
code in place. The client is calling the DllGetClassObje ct in library file
oleexp.cpp. I do not have my implementation of DllGetClassObje ct. If I
try
to implement my DllGetClassObje ct in the DLL code, the linker gives error
saying DllGetClassObje ct is already linked from oleexp.cpp.

What would I need to do to provide and use my implementation of
DllGetClassObje ct ?

The call to DllGetClassObje ct is currently failing with
CLASS_E_CLASSNO TAVAILABLE (ClassFactory cannot supply
requested class ), which I would assume is because of lack of CRT
initialization.

Thanks,
Niranjan

"Marcus Heege" wrote:

The intention of the delayed CRT initialization is to avoid a deadlock,
which can happen if managed code is executed during DLLMain. After
DLLMain
is called, your client will likely call DllGetClassObje ct to instantiate
the
COM object. Unless some other code is called before DllGetClassObje ct, I
would initialize the CRT in your DllGetClassObje ct implementation.

Marcus

"NPotnis" <NP*****@discus sions.microsoft .comwrote in message
news:5C******** *************** ***********@mic rosoft.com...
Hi ,

I am trying to host .Net UserControls in a MFC Application. The MFC
Application is an ActiveX DLL. I inserted required managed code inside
the
MFC application, making it a mixed mode DLL.
I am following the KB article for mixed mode DLL's
http://support.microsoft.com/?id=814472
I linked the DLL with /noentry option. Also I added and exported the
DllEnsureInit and DllForceTerm methods in my DLL which call
__crt_dll_initi alize() and __crt_dll_termi nate() respectively. So far
so
good.

Now in the consumer application, this ActiveX control is created
dynamically
by the COleControlSite ::CreateControl method. I understand that I would
need
to invoke my init/term DLL functions manually after loading the the
mixed
mode DLL.
How do I go about invoking these functions here ? The KB article
demonstrates use of GetModuleHandle and GetProcAddress which I believe
may
not be usefule

Is this feasible ? Kindly advise.
Any inputs would be highly appreciated.
Thanks in advance,
Niranjan

[NPotnis]

Marcus,
I have tried it your way too and it works as well. However I have still not
been able to find how does the linker permits multiply defined symbols in my
case, as I have mentioned in the previous post.
Thanks.

"NPotnis" wrote:

Hi Marcus,
Actually I did it in a different way and it works. Though it has taken me by
a bit of surprise. Heres the story - If I provide implementation of only
DllGetClassObje ct
the linker complains of multiply defined symbols. Same is the case if I just
implement DllCanUnloadNow . However if I implement both, the linker is happy
and moreover my implementations get used. I implemented both
DllGetClassObje ct and DllCanUnloadNow and put the CRT initilization in
DllGetClassObje ct. It worked.
What do you think have made this happen ? (is it an intelligent compiler /
linker ?)

Thanks,
Niranjan

"Marcus Heege" wrote:

I my answer, I assumed that you used ATL instead of MFC. In this case, it
would have been easy to overwrite DllGetClassObje ct.With MFC, the story is
more difficult. I currently don't have VS2003 installed on my machine.
Therefore, I can't easily try it before I suggest something. But you may try
the following:

Modify the .def file so that

EXPORTS
DllCanUnloadNow PRIVATE
DllGetClassObje ct = MyDllGetClassOb ject PRIVATE
DllRegisterServ er PRIVATE
DllUnregisterSe rver PRIVATE

Implement MyDllGetClassOb ject so that you initialize the CRT if this has not
happened before. Once you ensured that the CRT is initialized, call
DllGetClassObje ct.

Please let us know if this works

Marcus
"NPotnis" <NP*****@discus sions.microsoft .comwrote in message
news:3E******** *************** ***********@mic rosoft.com...

Hi Marcus,
Thanks for your reply.
>
I tried to investigate the current scenario without the CRT initialization
code in place. The client is calling the DllGetClassObje ct in library file
oleexp.cpp. I do not have my implementation of DllGetClassObje ct. If I
try
to implement my DllGetClassObje ct in the DLL code, the linker gives error
saying DllGetClassObje ct is already linked from oleexp.cpp.
>
What would I need to do to provide and use my implementation of
DllGetClassObje ct ?
>
The call to DllGetClassObje ct is currently failing with
CLASS_E_CLASSNO TAVAILABLE (ClassFactory cannot supply
requested class ), which I would assume is because of lack of CRT
initialization.
>
Thanks,
Niranjan
>
"Marcus Heege" wrote:
>
>The intention of the delayed CRT initialization is to avoid a deadlock,
>which can happen if managed code is executed during DLLMain. After
>DLLMain
>is called, your client will likely call DllGetClassObje ct to instantiate
>the
>COM object. Unless some other code is called before DllGetClassObje ct, I
>would initialize the CRT in your DllGetClassObje ct implementation.
>>
>Marcus
>>
>"NPotnis" <NP*****@discus sions.microsoft .comwrote in message
>news:5C******* *************** ************@mi crosoft.com...
Hi ,
>
I am trying to host .Net UserControls in a MFC Application. The MFC
Application is an ActiveX DLL. I inserted required managed code inside
the
MFC application, making it a mixed mode DLL.
I am following the KB article for mixed mode DLL's
http://support.microsoft.com/?id=814472
I linked the DLL with /noentry option. Also I added and exported the
DllEnsureInit and DllForceTerm methods in my DLL which call
__crt_dll_initi alize() and __crt_dll_termi nate() respectively. So far
so
good.
>
Now in the consumer application, this ActiveX control is created
dynamically
by the COleControlSite ::CreateControl method. I understand that I would
need
to invoke my init/term DLL functions manually after loading the the
mixed
mode DLL.
How do I go about invoking these functions here ? The KB article
demonstrates use of GetModuleHandle and GetProcAddress which I believe
may
not be usefule
>
Is this feasible ? Kindly advise.
Any inputs would be highly appreciated.
Thanks in advance,
Niranjan
>
>
>>
>>
>>