/* * plugin.h * * Plugin Class Declarations * * Portable Windows Library * * Contributor(s): Snark at GnomeMeeting * * $Log: plugin.h,v $ * Revision 1.11  2004/08/16 11:57:47  csoutheren * More changes for VS.net * * Revision 1.10  2004/08/16 10:55:09  csoutheren * Fixed problems compiling under Linux * * Revision 1.9  2004/08/16 06:40:59  csoutheren * Added adapters template to make device plugins available via the abstract factory interface * * Revision 1.8  2004/06/21 10:40:02  csoutheren * Fixed problem with dynamic plugins * * Revision 1.7  2004/06/21 00:57:40  csoutheren * Changed service plugin static registration to use attribute (( constructor )) * * Revision 1.6  2003/12/19 00:34:27  csoutheren * Ensured that older compilers do not get confused about functions wth empty * parameter lists. Thanks to Kilian Krause * * Revision 1.5  2003/11/19 09:29:19  csoutheren * Added super hack to avoid problems with multiple plugins in a single file * * Revision 1.4  2003/11/12 10:24:35  csoutheren * Changes to allow operation of static plugins under Windows * * Revision 1.3  2003/11/12 06:58:21  csoutheren * Changes to help in making static plugins autoregister under Windows * * Revision 1.2  2003/11/12 03:26:17  csoutheren * Initial version of plugin code from Snark of GnomeMeeting with changes *    by Craig Southeren os Post Increment * * */#ifndef _PLUGIN_H#define _PLUGIN_H//////////////////////////////////////////////////////////  these templates implement an adapter to make the old style device plugins appear in the new factory system//#include <ptlib/pfactory.h>template <class _Abstract_T, typename _Key_T = PString>class PDevicePluginFactory : public PFactory<_Abstract_T, _Key_T>{  public:    class Worker : public PFactory<_Abstract_T, _Key_T>::WorkerBase     {      public:        Worker(const _Key_T & key, bool singleton = false)          : PFactory<_Abstract_T, _Key_T>::WorkerBase(singleton)        {          PFactory<_Abstract_T, _Key_T>::Register(key, this);        }      protected:        virtual _Abstract_T * Create(const _Key_T & key) const;    };};class PDevicePluginAdapterBase{  public:    PDevicePluginAdapterBase()    { }    virtual ~PDevicePluginAdapterBase()    { }    virtual void CreateFactory(const PString & device) = 0;};template <typename DeviceBase>class PDevicePluginAdapter : public PDevicePluginAdapterBase{  public:    typedef PDevicePluginFactory<DeviceBase> Factory_T;    typedef typename Factory_T::Worker Worker_T;    void CreateFactory(const PString & device)    { new Worker_T(device, TRUE); }};#define PWLIB_PLUGIN_API_VERSION 0//////////////////////////////////////////////////////////  Ancestor Service descriptor for plugins//class PPluginServiceDescriptor {  public:    PPluginServiceDescriptor(unsigned (*_GetPluginAPIVersion)())      : GetPluginAPIVersion(_GetPluginAPIVersion)    { }    unsigned (*GetPluginAPIVersion)();};////////////////////////////////////////////////////////// Define a service provided by a plugin, which consists of the following:////    serviceType - the base class name of the service which is used to identify//                  the service type, such as PSoundChannel, ////    serviceName - the name of the service provided by the plugin. This will usually//                  be related to the class implementing the service, such as://                       service name = OSS, class name = PSoundChannelOSS////    descriptor  - a pointer to a class containing pointers to any static functions//                  for this class//   //class PPluginService: public PObject{  public:    PPluginService(const PString & _serviceName,                   const PString & _serviceType,                   PPluginServiceDescriptor *_descriptor)    {      serviceName = _serviceName;      serviceType = _serviceType;      descriptor  = _descriptor;    }    PString serviceName;    PString serviceType;    PPluginServiceDescriptor * descriptor;};//////////////////////////////////////////////////////#define PCREATE_PLUGIN_VERSION_DECLARE #define PCREATE_STATIC_PLUGIN_VERSION_FN(serviceName, serviceType) \unsigned PPlugin_##serviceType##_##serviceName##_GetVersion() \  { return PWLIB_PLUGIN_API_VERSION; } #define PCREATE_DYNAMIC_PLUGIN_VERSION_FN(serviceName, serviceType) \extern "C" unsigned PWLibPlugin_GetAPIVersion (void) \{ return PWLIB_PLUGIN_API_VERSION; } //////////////////////////////////////////////////////////  These crazy macros are needed to cause automatic registration of //  static plugins. They are made more complex by the arcane behaviour//  of the Windows link system that requires an external reference in the//  object module before it will instantiate any globals in in it//#define PCREATE_PLUGIN_REGISTERER(serviceName, serviceType, descriptor) \class PPlugin_##serviceType##_##serviceName##_Registration { \  public: \    PPlugin_##serviceType##_##serviceName##_Registration(PPluginManager * pluginMgr) \    { \      static PDevicePluginFactory<serviceType>::Worker factory(#serviceName); \      pluginMgr->RegisterService(#serviceName, #serviceType, descriptor); \    } \    int kill_warning; \}; \#ifdef _WIN32#define PCREATE_PLUGIN_STATIC(serviceName, serviceType, descriptor) \PCREATE_PLUGIN_REGISTERER(serviceName, serviceType, descriptor) \PPlugin_##serviceType##_##serviceName##_Registration \  PPlugin_##serviceType##_##serviceName##_Registration_Instance(&PPluginManager::GetPluginManager()); \#define PWLIB_STATIC_LOAD_PLUGIN(cls) \  class PPlugin_##cls##_Registration; \  extern PPlugin_##cls##_Registration PPlugin_##cls##_Registration_Instance; \  static PPlugin_##cls##_Registration * PPlugin_##cls##_Registration_Static_Library_Loader = &PPlugin_##cls##_Registration_Instance#else#define PCREATE_PLUGIN_STATIC(serviceName, serviceType, descriptor) \static void __attribute__ (( constructor )) PWLIB_StaticLoader_##serviceName##_##serviceType() \{ PPluginManager::GetPluginManager().RegisterService(#serviceName, #serviceType, descriptor); } \#define PWLIB_STATIC_LOAD_PLUGIN(cls) #endif#define PCREATE_PLUGIN_DYNAMIC(serviceName, serviceType, descriptor) \PCREATE_PLUGIN_REGISTERER(serviceName, serviceType, descriptor) \extern "C" void PWLibPlugin_TriggerRegister (PPluginManager * pluginMgr) { \PPlugin_##serviceType##_##serviceName##_Registration \     pplugin_##serviceType##_##serviceName##_Registration_Instance(pluginMgr); \     pplugin_##serviceType##_##serviceName##_Registration_Instance.kill_warning = 0; \} //////////////////////////////////////////////////////#if defined(P_HAS_PLUGINS) && ! defined(P_FORCE_STATIC_PLUGIN)#  define PCREATE_PLUGIN(serviceName, serviceType, descriptor) \    PCREATE_PLUGIN_DYNAMIC(serviceName, serviceType, descriptor)#  define PCREATE_PLUGIN_VERSION_FN(serviceName, serviceType) \    PCREATE_DYNAMIC_PLUGIN_VERSION_FN(serviceName, serviceType)#  define PPLUGIN_VERSION_FN(serviceName, serviceType) \    PWLibPlugin_GetAPIVersion#else#  define PCREATE_PLUGIN(serviceName, serviceType, descriptor) \    PCREATE_PLUGIN_STATIC(serviceName, serviceType, descriptor)#  define PCREATE_PLUGIN_VERSION_FN(serviceName, serviceType) \    PCREATE_STATIC_PLUGIN_VERSION_FN(serviceName, serviceType)#  define PPLUGIN_VERSION_FN(serviceName, serviceType) \    PPlugin_##serviceType##_##serviceName##_GetVersion#endif//////////////////////////////////////////////////////#endif