include/GaudiKernel/ServiceLocatorHelper.h

0001 /***********************************************************************************\
0002 * (c) Copyright 1998-2019 CERN for the benefit of the LHCb and ATLAS collaborations *
0003 *                                                                                   *
0004 * This software is distributed under the terms of the Apache version 2 licence,     *
0005 * copied verbatim in the file "LICENSE".                                            *
0006 *                                                                                   *
0007 * In applying this licence, CERN does not waive the privileges and immunities       *
0008 * granted to it by virtue of its status as an Intergovernmental Organization        *
0009 * or submit itself to any jurisdiction.                                             *
0010 \***********************************************************************************/
0011 #ifndef GAUDIKERNEL_SERVICELOCATORHELPER_H
0012 #define GAUDIKERNEL_SERVICELOCATORHELPER_H
0013
0014 #include <GaudiKernel/IService.h>
0015 #include <GaudiKernel/ISvcLocator.h>
0016 #include <GaudiKernel/SmartIF.h>
0017 #include <GaudiKernel/StatusCode.h>
0018 #include <string>
0019
0020 class InterfaceID;
0021 class MsgStream;
0022
0023 /** @class ServiceLocatorHelper
0024  *  @brief an helper to share the implementation of service() among the
0025  *         various kernel base classes
0026  */
0027 class GAUDI_API ServiceLocatorHelper {
0028 public:
0029   ServiceLocatorHelper( ISvcLocator& svcLoc, const INamedInterface& requester )
0030       : m_svcLoc( svcLoc )
0031       , m_msgLog( SmartIF<IMessageSvc>( &svcLoc ), requester.name() )
0032       , // use requester msg level
0033       m_requesterName( requester.name() ) {}
0034   ServiceLocatorHelper( ISvcLocator& svcLoc, std::string loggedName, std::string requesterName )
0035       : m_svcLoc( svcLoc )
0036       , m_msgLog( SmartIF<IMessageSvc>( &svcLoc ), std::move( loggedName ) )
0037       , // use requester msg level
0038       m_requesterName( std::move( requesterName ) ) {}
0039   ServiceLocatorHelper( ISvcLocator& svcLoc, std::string requesterName )
0040       : m_svcLoc( svcLoc )
0041       , m_msgLog( SmartIF<IMessageSvc>( &svcLoc ), requesterName )
0042       , // use requester msg level
0043       m_requesterName( std::move( requesterName ) ) {}
0044 #if !defined( GAUDI_V22_API ) || defined( G22_NEW_SVCLOCATOR )
0045   ServiceLocatorHelper( ISvcLocator&     svcLoc,
0046                         const MsgStream& log, // use requester msg level
0047                         std::string      requesterName )
0048       : m_svcLoc( svcLoc ), m_msgLog( log ), m_requesterName( std::move( requesterName ) ) {}
0049 #endif
0050
0051   StatusCode getService( std::string_view name, bool createIf, const InterfaceID& iid, void** ppSvc ) const {
0052     return createIf ? createService( name, iid, ppSvc ) : locateService( name, iid, ppSvc, true );
0053   }
0054
0055   StatusCode locateService( std::string_view name, const InterfaceID& iid, void** ppSvc, bool quiet = false ) const;
0056
0057   StatusCode createService( std::string_view name, const InterfaceID& iid, void** ppSvc ) const;
0058
0059   StatusCode createService( std::string_view type, std::string_view name, const InterfaceID& iid, void** ppSvc ) const;
0060
0061   SmartIF<IService> service( std::string_view name, const bool quiet = false, const bool createIf = true ) const;
0062
0063   template <typename T>
0064   SmartIF<T> service( std::string_view name, const bool quiet = false, const bool createIf = true ) const {
0065     return service( name, quiet, createIf ).as<T>();
0066   }
0067
0068 private:
0069   ISvcLocator*       serviceLocator() const { return &m_svcLoc; }
0070   MsgStream&         log() const { return m_msgLog; }
0071   const std::string& requesterName() const { return m_requesterName; }
0072   ISvcLocator&       m_svcLoc;
0073   mutable MsgStream  m_msgLog;
0074   std::string        m_requesterName;
0075 };
0076 #endif