include/GaudiKernel/ServiceLocatorHelper.h

0001 /***********************************************************************************\
0002 * (c) Copyright 1998-2024 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   [[deprecated( "use ServiceLocatorHelper(svcLoc, requesterName) instead" )]] ServiceLocatorHelper(
0046       ISvcLocator&     svcLoc,
0047       const MsgStream& log, // use requester msg level
0048       std::string      requesterName )
0049       : m_svcLoc( svcLoc ), m_msgLog( log ), m_requesterName( std::move( requesterName ) ) {}
0050 #endif
0051
0052   StatusCode getService( std::string_view name, bool createIf, const InterfaceID& iid, void** ppSvc ) const {
0053     return createIf ? createService( name, iid, ppSvc ) : locateService( name, iid, ppSvc, true );
0054   }
0055
0056   StatusCode locateService( std::string_view name, const InterfaceID& iid, void** ppSvc, bool quiet = false ) const;
0057
0058   StatusCode createService( std::string_view name, const InterfaceID& iid, void** ppSvc ) const;
0059
0060   StatusCode createService( std::string_view type, std::string_view name, const InterfaceID& iid, void** ppSvc ) const;
0061
0062   SmartIF<IService> service( std::string_view name, const bool quiet = false, const bool createIf = true ) const;
0063
0064   template <typename T>
0065   SmartIF<T> service( std::string_view name, const bool quiet = false, const bool createIf = true ) const {
0066     return service( name, quiet, createIf ).as<T>();
0067   }
0068
0069 private:
0070   ISvcLocator*       serviceLocator() const { return &m_svcLoc; }
0071   MsgStream&         log() const { return m_msgLog; }
0072   const std::string& requesterName() const { return m_requesterName; }
0073   ISvcLocator&       m_svcLoc;
0074   mutable MsgStream  m_msgLog;
0075   std::string        m_requesterName;
0076 };
0077 #endif