Bootstrap.cpp

Go to the documentation of this file.

//$Id: Bootstrap.cpp,v 1.14 2007/12/12 16:02:32 marcocle Exp $

#include <iostream>

#include "GaudiKernel/Bootstrap.h"
#include "GaudiKernel/System.h"

#include "GaudiKernel/IInterface.h"
#include "GaudiKernel/IAlgorithm.h"
#include "GaudiKernel/IService.h"
#include "GaudiKernel/IAppMgrUI.h"
#include "GaudiKernel/ISvcLocator.h"
#include "GaudiKernel/IClassManager.h"

#include "Reflex/PluginService.h"
using ROOT::Reflex::PluginService;


namespace Gaudi
{

  class BootSvcLocator : public implements1<ISvcLocator> {
  public:
    BootSvcLocator();
    virtual ~BootSvcLocator();
#if !defined(GAUDI_V22_API)|| defined(G22_NEW_SVCLOCATOR)
    virtual StatusCode getService( const Gaudi::Utils::TypeNameString& typeName,
                                   const InterfaceID& iid,
                                   IInterface*& pinterface );
    virtual StatusCode getService( const Gaudi::Utils::TypeNameString& typeName,
                                   IService*& svc,
                                   const bool createIf = true);
#endif
    virtual const std::list<IService*>& getServices( ) const;
    virtual bool existsService( const std::string& name ) const;

    virtual SmartIF<IService> &service(const Gaudi::Utils::TypeNameString &typeName, const bool createIf = true);

  };
}


static SmartIF<ISvcLocator> s_svclocInstance;
static SmartIF<IAppMgrUI>   s_appmgrInstance;

//------------------------------------------------------------------------------
IAppMgrUI* Gaudi::createApplicationMgr(const std::string& dllname,
                                       const std::string& factname)
//------------------------------------------------------------------------------
{
  // Allow not for multiple AppManagers: If already instantiated then just
  // return it
  if ( !s_appmgrInstance.isValid() )    {
    s_appmgrInstance = createApplicationMgrEx(dllname, factname);
    s_svclocInstance = s_appmgrInstance;
  }
  return s_appmgrInstance.get();
}

//------------------------------------------------------------------------------
IAppMgrUI* Gaudi::createApplicationMgrEx(const std::string& dllname,
                                         const std::string& factname)
//------------------------------------------------------------------------------
{
  StatusCode     status;
  IInterface*    iif;
  IAppMgrUI*     iappmgr;

  // Create an instance of the application Manager
  iif = Gaudi::createInstance( "ApplicationMgr", factname, dllname );
  if( iif == 0 ) {
    return 0;
  }
  // Locate few interfaces of the Application Manager
  status = iif->queryInterface( IAppMgrUI::interfaceID(), pp_cast<void>(&iappmgr) );
  if( status.isFailure() ) {
    return 0;
  }
  iif->release();
  return iappmgr;
}

//------------------------------------------------------------------------------
ISvcLocator* Gaudi::svcLocator()
//------------------------------------------------------------------------------
//
// A dual-stage boostrap mechanism is used to ensure an orderly startup
// of the ApplicationMgr. If this function is called before the singleton
// ApplicationMgr instance exists, a BootSvcLocator singleton instance is
// created. This responds to any subsequent requests for services by
// returning StatusCode::FAILURE, unless the ApplicationMgr singleton
// instance has been created in the interim. In this case, the BootSvcLocator
// forwards the request to the ApplicationMgr instance. The motiviation for
// this is to handle static object instances where the constructor attempts
// to locate services and would otherwise instantiate the ApplicationMgr
// instance in an unorderly manner. This logic requires that the
// ApplicationMgr instance is created explicitly.

{
  if( !s_svclocInstance.isValid() )   {
    IAppMgrUI* iappmgr = createApplicationMgr();
    if( iappmgr ) {
      s_svclocInstance = iappmgr;
      if( s_svclocInstance.isValid() ) {
        return s_svclocInstance;
      }
    }
    //---Reverted change to create a Minimal SvcLocator in case is requested before AppMgr is created
    //if( 0 == s_appmgrInstance ) {
    //  s_svclocInstance = new BootSvcLocator();
    //} else {
    //  StatusCode sc = s_appmgrInstance->queryInterface( ISvcLocator::interfaceID(),
    //                                                  pp_cast<void>(&s_svclocInstance) );
    //  if( sc.isSuccess() ) {
    //    return s_svclocInstance;
    //  }
    //}
  }
  return s_svclocInstance;
}

//------------------------------------------------------------------------------
ISvcLocator* Gaudi::setInstance(ISvcLocator* newInstance)
//------------------------------------------------------------------------------
{
  ISvcLocator* oldInstance = s_svclocInstance.get();
  s_svclocInstance = newInstance;
  s_appmgrInstance = s_svclocInstance;
  return oldInstance;
}

//------------------------------------------------------------------------------
IAppMgrUI* Gaudi::setInstance(IAppMgrUI* newInstance)
//------------------------------------------------------------------------------
{
  IAppMgrUI* oldInstance = s_appmgrInstance.get();
  s_appmgrInstance = newInstance;
  s_svclocInstance = s_appmgrInstance;
  return oldInstance;
}

//------------------------------------------------------------------------------
IInterface* Gaudi::createInstance( const std::string& name,
                                                const std::string& factname,
                                                const std::string& dllname)
//------------------------------------------------------------------------------
{

  IInterface* ii = PluginService::Create<IInterface*>(factname,(IInterface*)0);
  if ( ii ) return ii;
  IService* is = PluginService::Create<IService*>(factname, name, (ISvcLocator*)0);
  if ( is ) return is;
  IAlgorithm* ia = PluginService::Create<IAlgorithm*>(factname, name, (ISvcLocator*)0);
  if ( ia ) return ia;

  StatusCode status;
  void* libHandle = 0;
  status = System::loadDynamicLib( dllname, &libHandle);
  if ( status.isSuccess() )   {
    IInterface* ii = PluginService::Create<IInterface*>(factname, (IInterface*)0);
    if ( ii ) return ii;
    IService* is = PluginService::Create<IService*>(factname, name, (ISvcLocator*)0);
    if ( is ) return is;
    IAlgorithm* ia = PluginService::Create<IAlgorithm*>(factname, name, (ISvcLocator*)0);
    if ( ia ) return ia;

    return 0;
  }
  else {
    // DLL library not loaded. Try in the local module
    std::cout << System::getLastErrorString() << std::endl;
    std::cout << "Gaudi::Bootstrap: Not found DLL " << dllname << std::endl;
    return 0;
  }
}

namespace {
  class ShadowEntry    {
  public:
    std::string dllName;
    std::string facName;
    IFactory*   fac;
  public:
    ShadowEntry() {
    }
    ShadowEntry(const std::string& d, const std::string& n, const IFactory* f) {
      dllName = d;
      facName = n;
      fac     = const_cast<IFactory*>(f);
    }
    ShadowEntry(const ShadowEntry& copy)   {
      dllName = copy.dllName;
      facName = copy.facName;
      fac     = copy.fac;
    }
    ShadowEntry& operator=(const ShadowEntry& copy)   {
      dllName = copy.dllName;
      facName = copy.facName;
      fac     = copy.fac;
      return *this;
    }
  };
}

//------------------------------------------------------------------------------
IAppMgrUI* Gaudi::createApplicationMgr(const std::string& dllname )    {
//------------------------------------------------------------------------------
  return createApplicationMgr(dllname, "ApplicationMgr");
}

//------------------------------------------------------------------------------
IAppMgrUI* Gaudi::createApplicationMgr()    {
//------------------------------------------------------------------------------
  return createApplicationMgr("GaudiSvc", "ApplicationMgr");
}

//=======================================================================
// BootSvcLocator
//=======================================================================

static std::list<IService*> s_bootServices;
static SmartIF<IService>    s_bootService;
static SmartIF<IInterface>  s_bootInterface;

using Gaudi::BootSvcLocator;

BootSvcLocator::BootSvcLocator() {
}
BootSvcLocator::~BootSvcLocator() {
}

#if !defined(GAUDI_V22_API) || defined(G22_NEW_SVCLOCATOR)
StatusCode Gaudi::BootSvcLocator::getService( const Gaudi::Utils::TypeNameString& typeName,
                                       const InterfaceID& iid,
                                       IInterface*& pinterface ) {
  StatusCode sc = StatusCode::FAILURE;
  if ( s_appmgrInstance.isValid() ) {
    sc = s_svclocInstance->getService(typeName, iid, pinterface );
  } else {
    pinterface = s_bootInterface.get();
  }
  return sc;
}
StatusCode Gaudi::BootSvcLocator::getService( const Gaudi::Utils::TypeNameString& typeName,
                                       IService*& svc,
                                       const bool createIf ) {
  StatusCode sc = StatusCode::FAILURE;
  if ( s_appmgrInstance.isValid() ) {
    sc = s_svclocInstance->getService(typeName, svc, createIf );
  } else {
    svc = s_bootService.get();
  }
  return sc;
}
#endif

const std::list<IService*>& Gaudi::BootSvcLocator::getServices( ) const {
  StatusCode sc = StatusCode::FAILURE;
  if ( s_appmgrInstance.isValid() ) {
    return s_svclocInstance->getServices( );
  } else {
    return s_bootServices;
  }
}
bool Gaudi::BootSvcLocator::existsService( const std::string& name ) const {
  bool result = false;
  if ( s_appmgrInstance.isValid() ) {
    result = s_svclocInstance->existsService(name);
  }
  return result;
}


SmartIF<IService>& Gaudi::BootSvcLocator::service(const Gaudi::Utils::TypeNameString &typeName, const bool createIf) {
  if ( s_appmgrInstance.isValid() ) {
    return s_svclocInstance->service(typeName, createIf);
  } else {
    return s_bootService;
  }
}