path: root/TAO/orbsvcs/Fault_Detector/FT_FaultDetectorFactory_i.h

/* -*- C++ -*- */
//=============================================================================
/**
 *  @file    FT_FaultDetectorFactory_i.h
 *
 *  This file is part of Fault Tolerant CORBA.
 *  It declares the implementation of FaultDetectorFactory which
 *  creates and manages FaultDetectors as an agent for
 *  the ReplicationManager as defined in the FT CORBA specification.
 *
 *  @author Dale Wilson <wilson_d@ociweb.com>
 */
//=============================================================================

#ifndef FT_FAULTDETECTORFACTORY_I_H_
#define FT_FAULTDETECTORFACTORY_I_H_
#include /**/ "ace/pre.h"
#include "ace/ACE.h"
#include "ace/SString.h"
#if !defined (ACE_LACKS_PRAGMA_ONCE)
# pragma once
#endif /* ACE_LACKS_PRAGMA_ONCE */

/////////////////////////////////
// Includes needed by this header
#include <ace/Vector_T.h>
#include <orbsvcs/FT_FaultDetectorFactoryS.h>
#include <orbsvcs/FT_ReplicationManagerC.h>
#include <ace/Thread_Manager.h>


TAO_BEGIN_VERSIONED_NAMESPACE_DECL

/////////////////////
// Forward references

/**
 * Implement the FaultDetectorFactory interface.
 *
 * Because each FaultDetector runs in a separate thread, care
 * must be taken to insure that the thread comes to an end, and
 * that the Fault_Detector_i object is deleted at the right time.
 * Hence, the FaultDetector life cycle:
 *  Creation:
 *  The create_object method of the factory creates a Fault_Detector_i
 *
 *  A pointer to the Fault_Detector_i is stored in the detectors_ table.
 *
 *  The start method of the Fault_Detector_i is called to create a thread
 *  that will monotor the object-to-be-monitored.  An ACE_Thread_Manager
 *  supplied by the factory is used to keep track of the thread.
 *
 *  Destruction:
 *
 *  If the factory wants the detector to go away, it calls the
 *  quitRequested method of the detector which sets a flag that must
 *  be checked regularly by the detector.
 *
 *  If the object being monitored faults, the detector sends the
 *  notification message then sets its own quit requested flag.
 *
 *  When a detector discovers the quit requested flag has been set
 *  it calls the remove_detector method of the factory, then ends
 *  the thread.
 *
 *  The remove_detector method of the factory removes the detector from
 *  the detectors_ collection, then deletes the Fault_Detector_i object.
 *
 *  Shutdown:
 *
 *  The destructor of the factory calls the shutdown method of all
 *  remaining Fault_Detector_i objects.
 *
 *  It then closes the ACE_Thread_Manager to ensure that all
 *  detector threads have departed before the factory itself is
 *  deleted.
 */

namespace TAO
{
  /////////////////////
  // Forward references
  class Fault_Detector_i;

  /////////////////////
  // Class Declarations
  class  FT_FaultDetectorFactory_i : public virtual POA_FT::FaultDetectorFactory
  {
    typedef ACE_Vector<Fault_Detector_i *> DetectorVec;

    //////////////////////
    // non-CORBA interface
  public:
    /**
     * Default constructor.
     */
    FT_FaultDetectorFactory_i ();

    /**
     * Virtual destructor.
     */
    virtual ~FT_FaultDetectorFactory_i ();

    /**
     * Parse command line arguments.
     * @param argc traditional C argc
     * @param argv traditional C argv
     * @return zero for success; nonzero is process return code for failure.
     */
    int parse_args (int argc, ACE_TCHAR * argv[]);

    /**
     * Initialize this object.
     * @param orb our ORB -- we keep var to it.
     * @return zero for success; nonzero is process return code for failure.
     */
    int init (CORBA::ORB_ptr orb);

    /**
     * Prepare to exit.
     * @return zero for success; nonzero is process return code for failure.
     */
    int fini (void);

    /**
     * Idle-time activity.
     *
     * @param result is set to process return code if return value is non-zero.
     * @return zero to continue; nonzero to exit
     */
    int idle(int & result);


    /**
     * Identify this fault detector factory.
     * @return a string to identify this object for logging/console message purposes.
     */
    const char * identity () const;

    /**
     * Remove pointer to individual detector; delete Fault_Detector_i.
     * See FaultDetector life cycle description.
     * @param id the numerical id assigned to this FaultDetector.
     * @param detector a pointer to the detector object (redundant for safety.)
     */
    void remove_detector (CORBA::ULong id, Fault_Detector_i * detector);

    //////////////////
    // CORBA interface
    // See IDL for documentation

    ///////////////////////////////////////////////
    // CORBA interface FaultDetectorFactory methods
    virtual void change_properties (
        const PortableGroup::Properties & property_set
      );

    virtual void shutdown (void);

    /////////////////////////////////////////
    // CORBA interface GenericFactory methods
    virtual CORBA::Object_ptr create_object (
      const char * type_id,
      const PortableGroup::Criteria & the_criteria,
      PortableGroup::GenericFactory::FactoryCreationId_out factory_creation_id
    );

    virtual void delete_object (
      const PortableGroup::GenericFactory::FactoryCreationId & factory_creation_id
    );

    //////////////////////////////////////////
    // CORBA interface PullMonitorable methods

    virtual CORBA::Boolean is_alive (void);

    /////////////////////////
    // Implementation methods
  private:
    /**
     * Find or allocate an ID for a new detector
     */
    CORBA::ULong allocate_id();

    /**
     * Write this factory's IOR to a file
     */
    int write_ior ();

    /**
     * Clean house for factory shut down.
     */
    void shutdown_i ();

    ///////////////
    // Data Members
  private:

    /**
     * Protect internal state.
     * Mutex should be locked by corba methods, or by
     * external (public) methods before calling implementation
     * methods.
     * Implementation methods should assume the mutex is
     * locked if necessary.
     */
    TAO_SYNCH_MUTEX internals_;

    /**
     * The orb
     */
    CORBA::ORB_var orb_;

    /**
     * The POA used to activate this object.
     */
    PortableServer::POA_var poa_;

    /**
     * The CORBA object id assigned to this object.
     */
    PortableServer::ObjectId_var objectId_;


    /**
     * IOR of this object as assigned by orb.
     */
    CORBA::String_var ior_;

    /**
     * A file to which the factory's IOR should be written.
     */
    const ACE_TCHAR * ior_output_file_;

    /**
     * A name to be used to register the factory with the name service.
     */
    const char * ns_name_;

    ::CosNaming::NamingContext_var naming_context_;

    ::CosNaming::Name this_name_;

    /**
     * Quit on idle flag.
     */
    int quit_on_idle_;

    /**
     * the FT::Domain where we're operating
     */
    PortableGroup::GroupDomainId domain_;

    /**
     * the FT::Location within the domain
     */
    PortableGroup::Location location_;

    /**
     * the notifer to use by default
     */

    FT::FaultNotifier_var notifier_;

    /**
     * bool: if true, register with ReplicationManager.
     * default is true.  -x turns it off.
     */
    int rm_register_;

    /**
     * the replication manager
     */
    ::FT::ReplicationManager_var replication_manager_;

    /**
     * bool: if true the registration with ReplicationManager was successful.
     */
    int registered_;

    /**
     * The factory registry with which to register.
     */
    PortableGroup::FactoryRegistry_var factory_registry_;

    /**
     * A human-readable string to distinguish this from other Notifiers.
     */
    ACE_CString identity_;

    /**
     * A manager for all FaultDetector threads.
     */
    ACE_Thread_Manager threadManager_;

    /**
     * A vector of FaultDetectors.  Note that the FaultDetector ID
     * is an index into this vector.
     */
    DetectorVec detectors_;

    /**
     * count of empty entries in detectors_
     * Used to determine when the factory is idle, and to avoid
     * fruitless searches for empty slots.
     */
    size_t empty_slots_;

    /**
     * boolean: starts false.  Set to true when it's time to quit.
     */
    int quit_requested_;
  };
}   // namespace TAO

TAO_END_VERSIONED_NAMESPACE_DECL

#include /**/ "ace/post.h"
#endif /* FT_FAULTDETECTORFACTORY_I_H_  */