Fake COM to real COM about potto HOT 1 CLOSED

Hi @yyokyfo , thanks for your inspired question. Potto is only a minimal subset implementation of MS COM concept and it exposed the same IUnknown interface of the object, theoretically speaking you can consume the potto object in MS COM runtime as long as you can get the object instance created by potto. If you would like to try you can make some modification of Potto as follow instructions:

1. compile Potto with POTTO_USE_GUID enabled, because MS COM uses real GUID but potto uses string by default:
   

   potto/include/potto/pottouuid.hpp

   Line 19 in 8f2b1d3

   #ifdef POTTO_USE_GUID

2. change the UUID value of Potto::IUnknown({10000000-0000-0000-0000-000000000000}), you need to change the UUID to the value which exactly the same with MS IUnknown({00000000-0000-0000-C000-000000000046}) :
   

   potto/include/potto/pottointerface.hpp

   Line 16 in 8f2b1d3

   const char* const IID_IUnknown = "10000000-0000-0000-0000-000000000000";

3. change the UUID value of Potto::IClassFactory({10000000-0000-0000-0000-100000000001}) to MS IClassFactory({0000001B-0000-0000-C000-000000000046}):
   

   potto/include/potto/pottointerface.hpp

   Line 48 in 8f2b1d3

   const char* const IID_IClassFactory = "10000000-0000-0000-0000-100000000001";

4. then you should initialize and create potto object by Potto methods:
   initialize potto runtime
   

   potto/include/potto/potto.h

   Line 47 in 8f2b1d3

   POTTO_API POTTO_ERROR Initialize(const std::string& moduleDatabase,

   
   ceate instance and get interface
   

   potto/include/potto/potto.h

   Line 65 in 8f2b1d3

   POTTO_API POTTO_ERROR CreateInstance(const PottoUuid& classId, const PottoUuid& interfaceId,

   
   or
   

   potto/include/potto/potto.h

   Line 83 in 8f2b1d3

   POTTO_API POTTO_ERROR GetClassObject(const PottoUuid& classId, const PottoUuid& interfaceId,

then you can pass the interface to MS COM runtime methods.

limitatios of Potto

• No complex apartment models
• No Dispatch supports
• No Windows registry available

Good luck~

from potto.