ImR_Locator_i.cpp

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// $Id: ImR_Locator_i.cpp 78858 2007-07-12 23:24:55Z sowayaa $

#include "ImR_Locator_i.h"
#include "utils.h"
#include "Iterator.h"
#include "INS_Locator.h"

#include "orbsvcs/Time_Utilities.h"

#include "tao/IORTable/IORTable.h"
#include "tao/PortableServer/PortableServer.h"
#include "tao/ORB_Core.h"
#include "tao/default_ports.h"
#include "tao/Messaging/Messaging.h"
#include "tao/AnyTypeCode/Any.h"

#include "ace/ARGV.h"
#include "ace/OS_NS_sys_time.h"
#include "ace/Vector_T.h"

static const int DEFAULT_START_LIMIT = 1;

static const int PING_RETRY_SCHEDULE[] = {0, 10, 100, 500, 1000, 1000, 1000, 1000, 5000, 5000};

static const ACE_Time_Value DEFAULT_SERVER_TIMEOUT (0, 10 * 1000); // 10ms
// We want to give shutdown a little more time to work, so that we
// can guarantee to the tao_imr utility that it has shutdown. The tao_imr
// utility prints a different message depending on whether shutdown succeeds
// or times out.
static const ACE_Time_Value DEFAULT_SHUTDOWN_TIMEOUT (0, 5000 * 1000);

static PortableServer::POA_ptr
createPersistentPOA (PortableServer::POA_ptr root_poa, const char* poa_name) {

  PortableServer::LifespanPolicy_var life =
    root_poa->create_lifespan_policy (PortableServer::PERSISTENT);

  PortableServer::IdAssignmentPolicy_var assign =
    root_poa->create_id_assignment_policy (PortableServer::USER_ID);

  CORBA::PolicyList pols;
  pols.length (2);
  pols[0] = PortableServer::LifespanPolicy::_duplicate (life.in ());
  pols[1] = PortableServer::IdAssignmentPolicy::_duplicate (assign.in ());

  PortableServer::POAManager_var mgr = root_poa->the_POAManager ();
  PortableServer::POA_var poa =
    root_poa->create_POA (poa_name, mgr.in (), pols);

  life->destroy ();
  assign->destroy ();

  return poa._retn ();
}

ImR_Locator_i::ImR_Locator_i (void)
  : forwarder_ (*this)
  , ins_locator_ (0)
  , debug_ (0)
  , read_only_ (false)
{
  // Visual C++ 6.0 is not smart enough to do a direct assignment
  // while allocating the INS_Locator.  So, we have to do it in
  // two steps.
  INS_Locator* locator;
  ACE_NEW (locator,
          INS_Locator (*this));
  ins_locator_ = locator;
}

ImR_Locator_i::~ImR_Locator_i (void)
{
  // For some reason g++ 4.0 needs this out-of-line destructor instead
  // of the default one generated by the compiler.  Without this
  // destructor, we get a number of "undefined reference" link errors
  // related to the virtual tables of the INS_Locator, ImR_Adapter and
  // ImR_Forwarder members in this class.
}

int
ImR_Locator_i::init_with_orb (CORBA::ORB_ptr orb, Options& opts)
{
  orb_ = CORBA::ORB::_duplicate (orb);
  debug_ = opts.debug ();
  read_only_ = opts.readonly ();
  startup_timeout_ = opts.startup_timeout ();
  ping_interval_ = opts.ping_interval ();

  CORBA::Object_var obj =
    this->orb_->resolve_initial_references ("RootPOA");
  this->root_poa_ = PortableServer::POA::_narrow (obj.in ());
  ACE_ASSERT (! CORBA::is_nil (this->root_poa_.in ()));

  this->forwarder_.init (orb);
  this->adapter_.init (& this->forwarder_);

  // Register the Adapter_Activator reference to be the RootPOA's
  // Adapter Activator.
  root_poa_->the_activator (&this->adapter_);

  // Use a persistent POA so that any IOR
  this->imr_poa_ = createPersistentPOA (this->root_poa_.in (),
                                        "ImplRepo_Service");
  ACE_ASSERT (! CORBA::is_nil (this->imr_poa_.in ()));

  waiter_svt_.debug (debug_ > 1);
  PortableServer::ObjectId_var id = PortableServer::string_to_ObjectId ("ImR_AsyncStartupWaiter");
  this->imr_poa_->activate_object_with_id (id.in (), &waiter_svt_);
  obj = this->imr_poa_->id_to_reference (id.in ());
  if (startup_timeout_ > ACE_Time_Value::zero)
    {
      obj = set_timeout_policy (obj.in (), startup_timeout_);
    }
  waiter_ = ImplementationRepository::AsyncStartupWaiter::_narrow (obj.in ());

  id = PortableServer::string_to_ObjectId ("ImplRepo_Service");
  this->imr_poa_->activate_object_with_id (id.in (), this);

  obj = this->imr_poa_->id_to_reference (id.in ());
  CORBA::String_var ior = this->orb_->object_to_string (obj.in ());

  // Register the ImR for use with INS
  obj = orb->resolve_initial_references ("IORTable");
  IORTable::Table_var ior_table = IORTable::Table::_narrow (obj.in ());
  ACE_ASSERT (! CORBA::is_nil (ior_table.in ()));
  ior_table->bind ("ImplRepoService", ior.in ());
  ior_table->bind ("ImR", ior.in ());
  ior_table->set_locator (this->ins_locator_.in ());

  // Set up multicast support (if enabled)
  if (opts.multicast ())
    {
      ACE_Reactor* reactor = orb->orb_core ()->reactor ();
      if (this->setup_multicast (reactor, ior.in ()) != 0)
        return -1;
    }

  // Initialize the persistent storage. This will load any values that
  // may have been persisted before.
  // The init can return 1 if there is no persistent file yet. In
  // that case, we need not do anything for now.
  int init_result =
    this->repository_.init (opts);
  if (init_result == -1)
    {
      ACE_ERROR_RETURN ((LM_ERROR, "Repository failed to initialize\n"), -1);
    }

  // Activate the two poa managers
  PortableServer::POAManager_var poaman =
    this->root_poa_->the_POAManager ();
  poaman->activate ();
  poaman = this->imr_poa_->the_POAManager ();
  poaman->activate ();

  // We write the ior file last so that the tests can know we are ready.
  if (opts.ior_filename ().length () > 0)
    {
      FILE* fp = ACE_OS::fopen (opts.ior_filename ().c_str (), "w");
      if (fp == 0)
        {
          ACE_ERROR_RETURN ((LM_ERROR,
                             "ImR: Could not open file: %s\n", opts.ior_filename ().c_str ()), -1);
        }
      ACE_OS::fprintf (fp, "%s", ior.in ());
      ACE_OS::fclose (fp);
    }

  return 0;
}

int
ImR_Locator_i::init (Options& opts)
{
  ACE_CString cmdline = opts.cmdline ();
  cmdline += " -orbcollocation no -orbuseimr 0";
  ACE_ARGV av (cmdline.c_str ());
  int argc = av.argc ();
  char** argv = av.argv ();

  CORBA::ORB_var orb = CORBA::ORB_init (argc, argv, "TAO_ImR_Locator");
  int err = this->init_with_orb (orb.in (), opts);
  return err;
}

int
ImR_Locator_i::run (void)
{
  if (debug_ > 0)
    {
      // This debug message was split into two calls to
      // work around yet another bug in Visual Studio 2005.
      // When this was a single debug message, the value for
      // debug () came out garbled and the read-only string
      // caused an ACCESS VIOLATION -- Chad Elliott 10/4/2006
      ACE_DEBUG ((LM_DEBUG,
                  "Implementation Repository: Running\n"
                  "\tPing Interval : %dms\n"
                  "\tStartup Timeout : %ds\n"
                  "\tPersistence : %s\n"
                  "\tMulticast : %s\n",
                  ping_interval_.msec (),
                  startup_timeout_.sec (),
                  repository_.repo_mode (),
                  ior_multicast_.reactor () != 0 ? "Enabled" : "Disabled"));
      ACE_DEBUG ((LM_DEBUG,
                  "\tDebug : %d\n"
                  "\tLocked : %s\n\n",
                  debug (),
                  read_only_ ? "True" : "False"));
    }
  this->auto_start_servers ();

  this->orb_->run ();
  return 0;
}

void
ImR_Locator_i::shutdown (CORBA::Boolean activators, CORBA::Boolean servers)
{
  if (servers != 0 && this->repository_.servers ().current_size () > 0)
    {
      // Note : shutdown is oneway, so we can't throw
      ACE_ERROR ((LM_ERROR, "ImR: Shutdown of all servers not implemented.\n"));
    }
  if (activators != 0 && this->repository_.activators ().current_size () > 0)
    {
      ACE_Vector<ImplementationRepository::Activator_var> acts;
      Locator_Repository::AIMap::ENTRY* entry = 0;
      Locator_Repository::AIMap::ITERATOR it (this->repository_.activators ());
      for (;it.next (entry) != 0; it.advance ())
        {
          Activator_Info_Ptr info = entry->int_id_;
          ACE_ASSERT (! info.null ());
          connect_activator (*info);
          if (! CORBA::is_nil (info->activator.in ()))
            acts.push_back (info->activator);
        }

      int shutdown_errs = 0;

      for (size_t i = 0; i < acts.size (); ++i)
        {
          try
            {
              acts[i]->shutdown ();
              acts[i] = ImplementationRepository::Activator::_nil ();
            }
          catch (const CORBA::Exception& ex)
            {
              ++shutdown_errs;
              if (debug_ > 1)
                {
                  ex._tao_print_exception (
                    "ImR: shutdown activator");
                }
            }
        }
      if (debug_ > 0 && shutdown_errs > 0)
        {
          ACE_DEBUG ((LM_DEBUG, "ImR: Some activators could not be shut down.\n"));
        }
    }
  // Technically, we should wait for all the activators to unregister, but
  // ,for now at least, it doesn't seem worth it.
  this->shutdown (false);
}

void
ImR_Locator_i::shutdown (bool wait_for_completion)
{
  this->orb_->shutdown (wait_for_completion);
}

int
ImR_Locator_i::fini (void)
{
  try
    {
      if (debug_ > 1)
        ACE_DEBUG ((LM_DEBUG, "ImR: Shutting down...\n"));

      teardown_multicast ();

      this->root_poa_->destroy (1, 1);

      this->orb_->destroy ();

      if (debug_ > 0)
        ACE_DEBUG ((LM_DEBUG, "ImR: Shut down successfully.\n"));
    }
  catch (const CORBA::Exception& ex)
    {
      ex._tao_print_exception ("ImR_Locator_i::fini");
      throw;
    }
  return 0;
}

void
ImR_Locator_i::teardown_multicast ()
{
  ACE_Reactor* r = ior_multicast_.reactor ();
  if (r != 0) {
    r->remove_handler (&ior_multicast_, ACE_Event_Handler::READ_MASK);
    ior_multicast_.reactor (0);
  }
}

int
ImR_Locator_i::setup_multicast (ACE_Reactor* reactor, const char* ior)
{
  ACE_ASSERT (reactor != 0);
  ACE_ASSERT (ior != 0);
#if defined (ACE_HAS_IP_MULTICAST)

  TAO_ORB_Core* core = TAO_ORB_Core_instance ();
  // See if the -ORBMulticastDiscoveryEndpoint option was specified.
  ACE_CString mde (core->orb_params ()->mcast_discovery_endpoint ());

  if (mde.length () != 0)
    {
      if (this->ior_multicast_.init (ior,
                                     mde.c_str (), TAO_SERVICEID_IMPLREPOSERVICE) == -1)
        {
          return -1;
        }
    }
  else
    {
      // Port can be specified as param, env var, or default
      CORBA::UShort port =
        core->orb_params ()->service_port (TAO::MCAST_IMPLREPOSERVICE);
      if (port == 0)
        {
          // Check environment var. for multicast port.
          const char* port_number = ACE_OS::getenv ("ImplRepoServicePort");

          if (port_number != 0)
            port = static_cast<CORBA::UShort> (ACE_OS::atoi (port_number));
        }
      if (port == 0)
        port = TAO_DEFAULT_IMPLREPO_SERVER_REQUEST_PORT;

      if (this->ior_multicast_.init (ior, port,
                                     ACE_DEFAULT_MULTICAST_ADDR, TAO_SERVICEID_IMPLREPOSERVICE) == -1)
        {
          return -1;
        }
    }

  // Register event handler for the ior multicast.
  if (reactor->register_handler (&this->ior_multicast_,
                                 ACE_Event_Handler::READ_MASK) == -1)
    {
      if (debug_ >= 1)
        ACE_DEBUG ((LM_DEBUG, "ImR: cannot register Event handler\n"));
      return -1;
    }
#else /* ACE_HAS_IP_MULTICAST*/
  ACE_UNUSED_ARG (reactor);
  ACE_UNUSED_ARG (ior);
#endif /* ACE_HAS_IP_MULTICAST*/
  return 0;
}

CORBA::Long
ImR_Locator_i::register_activator (const char* aname,
                                   ImplementationRepository::Activator_ptr activator)
{
  ACE_ASSERT (aname != 0);
  ACE_ASSERT (! CORBA::is_nil (activator));

  // Before we can register the activator, we need to ensure that any existing
  // registration is purged.
  this->unregister_activator_i (aname);

  CORBA::String_var ior =
    this->orb_->object_to_string (activator);

  CORBA::Long token = ACE_OS::gettimeofday ().msec ();

  int err = this->repository_.add_activator (aname, token, ior.in (), activator);
  ACE_ASSERT (err == 0);
  ACE_UNUSED_ARG (err);

  if (this->debug_ > 0)
    ACE_DEBUG ((LM_DEBUG, "ImR: Activator registered for %s.\n", aname));

  return token;
}

void
ImR_Locator_i::unregister_activator (const char* aname,
                                     CORBA::Long token)
{
  ACE_ASSERT (aname != 0);
  Activator_Info_Ptr info = this->get_activator (aname);

  if (! info.null ())
    {
      if (info->token != token && this->debug_ > 0)
        {
          ACE_DEBUG ((LM_DEBUG, "ImR: Ignoring unregister activator:%s. Wrong token.\n", aname));
          return;
        }

      this->unregister_activator_i (aname);

      if (this->debug_ > 0)
        ACE_DEBUG ((LM_DEBUG, "ImR: Activator %s unregistered.\n", aname));
    }
  else
    {
      if (this->debug_ > 0)
        ACE_DEBUG ((LM_DEBUG, "ImR: Ignoring unregister activator:%s. Unknown activator.\n", aname));
    }
}

void
ImR_Locator_i::unregister_activator_i (const char* aname)
{
  ACE_ASSERT (aname != 0);
  int err = this->repository_.remove_activator (aname);
  ACE_UNUSED_ARG (err);
}

void
ImR_Locator_i::notify_child_death (const char* name)
{
  ACE_ASSERT (name != 0);

  if (this->debug_ > 1)
    ACE_DEBUG ((LM_DEBUG, "ImR: Server has died <%s>.\n", name));

  Server_Info_Ptr info = this->repository_.get_server (name);
  if (! info.null ())
    {
      info->ior = "";
      info->partial_ior = "";

      int err = this->repository_.update_server (*info);
      ACE_ASSERT (err == 0);
      ACE_UNUSED_ARG (err);
    }
  else
    {
      if (this->debug_ > 1)
        ACE_DEBUG ((LM_DEBUG,
                    "ImR: Failed to find server in repository.\n"));
    }
}

void
ImR_Locator_i::activate_server (const char* server)
{
  if (debug_ > 1)
    ACE_DEBUG ((LM_DEBUG, "ImR: Manually activating server <%s>\n", server));

  // This is the version called by tao_imr to activate the server, manually
  // starting it if necessary.
  activate_server_by_name (server, true);
}

char*
ImR_Locator_i::activate_server_by_name (const char* name, bool manual_start)
{
  // Activate the server, starting it if necessary. Don't start MANUAL
  // servers unless manual_start=true
  ACE_ASSERT (name != 0);

  Server_Info_Ptr info = this->repository_.get_server (name);
  if (info.null ())
    {
      ACE_ERROR ((LM_ERROR, "ImR: Cannot find info for server <%s>\n", name));
      throw ImplementationRepository::NotFound ();
    }

  return activate_server_i (*info, manual_start);
}

char*
ImR_Locator_i::activate_server_by_object (const char* object_name)
{
  ACE_ASSERT (object_name != 0);

  // We assume that the first part of the object name is the server name.
  // So a name of foo/bar means that the server name is foo.
  ACE_CString server_name (object_name);
  ACE_CString::size_type pos = server_name.find ('/');
  if (pos != ACE_CString::npos)
    server_name = server_name.substr (pos + 1);

  return activate_server_by_name (server_name.c_str (), false);
}

char*
ImR_Locator_i::activate_server_i (Server_Info& info, bool manual_start)
{
  if (info.activation_mode == ImplementationRepository::PER_CLIENT)
    {
      return activate_perclient_server_i (info, manual_start);
    }

  while (true)
    {
      if (is_alive (info))
        {
          if (debug_ > 1)
            {
              ACE_DEBUG ((LM_DEBUG, "ImR: Successfully activated <%s> at \n\t%s\n",
                          info.name.c_str (), info.partial_ior.c_str ()));
            }
          info.start_count = 0;

          waiter_svt_.unblock_all (info.name.c_str ());

          return CORBA::string_dup (info.partial_ior.c_str ());
        }

      info.reset ();

      if (! info.starting && info.start_count >= info.start_limit)
        {
          if (this->debug_ > 0)
            {
              ACE_DEBUG ((LM_DEBUG,
                          "ImR: Cannot Activate <%s>.\n", info.name.c_str ()));
            }

          waiter_svt_.unblock_all (info.name.c_str ());

          throw ImplementationRepository::CannotActivate(
            CORBA::string_dup (
              "Cannot start server."));
        }

      // Note: We already updated info with StartupInfo in server_is_running ()
      ImplementationRepository::StartupInfo_var si =
        start_server (info, manual_start, info.waiting_clients);
    }
}

char*
ImR_Locator_i::activate_perclient_server_i (Server_Info info, bool manual_start)
{
  Server_Info_Ptr shared_info = this->repository_.get_server (info.name);
  do
    {
      ImplementationRepository::StartupInfo* psi =
        start_server (info, manual_start, shared_info->waiting_clients);

      if (psi != 0)
        {
          ImplementationRepository::StartupInfo_var si = psi;
          ACE_ASSERT (info.name == si->name.in ());
          info.partial_ior = si->partial_ior.in ();
          info.ior = si->ior.in ();

          if (is_alive (info))
            {
              if (debug_ > 1)
                {
                  ACE_DEBUG ((LM_DEBUG, "ImR: Successfully activated <%s> at \n\t%s\n",
                              info.name.c_str (), info.partial_ior.c_str ()));
                }
              return CORBA::string_dup (info.partial_ior.c_str ());
            }
          info.reset ();
        }
    } while (info.start_count < info.start_limit);

  if (this->debug_ > 0)
    {
      ACE_DEBUG ((LM_DEBUG,
                  "ImR: Cannot Activate <%s>.\n", info.name.c_str ()));
    }
  throw ImplementationRepository::CannotActivate(
    CORBA::string_dup (
      "Cannot start server."));
}

ImplementationRepository::StartupInfo*
ImR_Locator_i::start_server (Server_Info& info, bool manual_start,
                             int& waiting_clients)
{
  if (info.activation_mode == ImplementationRepository::MANUAL && ! manual_start)
    {
      if (debug_ > 0)
        ACE_DEBUG ((LM_DEBUG, "ImR: Cannot start server <%s>. ActivationMode=MANUAL\n", info.name.c_str ()));
      throw ImplementationRepository::CannotActivate(
        CORBA::string_dup (
          "Cannot implicitly activate MANUAL server."));
    }
  if (info.cmdline.length () == 0)
    {
      if (debug_ > 0)
        ACE_DEBUG ((LM_DEBUG, "ImR: Cannot start server <%s>."
                    " No command line.\n", info.name.c_str ()));
      throw ImplementationRepository::CannotActivate(
        CORBA::string_dup (
          "No command line registered for server."));
    }

  Activator_Info_Ptr ainfo = get_activator (info.activator);

  if (ainfo.null () || CORBA::is_nil (ainfo->activator.in ()))
    {
      if (debug_ > 0)
        ACE_DEBUG ((LM_DEBUG, "ImR: Cannot start server <%s>. "
                    "Activator <%s> not found.\n", info.name.c_str (), info.activator.c_str ()));
      throw ImplementationRepository::CannotActivate(
        CORBA::string_dup (
          "No activator registered for server."));
    }

  try
    {
      ++waiting_clients;

      if (waiting_clients <= 1 ||
          info.activation_mode == ImplementationRepository::PER_CLIENT)
        {
          info.starting = true;
          ++info.start_count;
          ACE_ASSERT (info.start_count <= info.start_limit);
          if (this->debug_ > 0)
            {
              ACE_DEBUG ((LM_DEBUG, "ImR: Starting server <%s>. Attempt %d/%d.\n",
                          info.name.c_str (), info.start_count, info.start_limit));
            }
          ainfo->activator->start_server (
                                          info.name.c_str (),
                                          info.cmdline.c_str (),
                                          info.dir.c_str (),
                                          info.env_vars);
        }

      if (info.partial_ior.length () == 0)
        {
          if (this->debug_ > 0)
            {
              ACE_DEBUG ((LM_DEBUG, "ImR: Waiting for <%s> to start...\n", info.name.c_str ()));
            }

          ImplementationRepository::StartupInfo_var si =
            waiter_->wait_for_startup (info.name.c_str ());

          --waiting_clients;
          info.starting = false;

          return si._retn ();
        }
      else // The server_is_running () came in before the wait_for_startup ()
        {
          if (this->debug_ > 0)
            {
              ACE_DEBUG ((LM_DEBUG, "ImR: <%s> Skipping wait. Already started.\n", info.name.c_str ()));
            }
          --waiting_clients;
          info.starting = false;
        }
    }
  catch (const CORBA::TIMEOUT&)
    {
      --waiting_clients;
      info.starting = false;
      // We may have connected successfully, because the timeout could occur before
      // the AsyncStartupWaiter manages to return. In fact, when the ImR is very busy
      // this is the most likely code path.
      if (info.partial_ior.length () == 0)
        {
          if (debug_ > 0)
            ACE_DEBUG ((LM_DEBUG, "ImR : Timeout waiting for <%s> to start.\n", info.name.c_str ()));
          info.reset ();
        }
    }
  catch (const ImplementationRepository::CannotActivate&)
    {
      --waiting_clients;
      info.starting = false;
      info.reset ();
      if (debug_ > 0)
        ACE_DEBUG ((LM_DEBUG, "ImR: Activator cannot start <%s>.\n", info.name.c_str ()));
    }
  catch (const CORBA::Exception& ex)
    {
      --waiting_clients;
      info.starting = false;
      if (debug_ > 0)
        ACE_DEBUG ((LM_DEBUG, "ImR: Unexpected exception while starting <%s>.\n", info.name.c_str ()));
      if (debug_ > 1)
        ex._tao_print_exception ("");
      info.reset ();

      // Before we reset the activator info, let's see if it's still
      // there then let's keep it around for a while.
      bool dead_activator = false;
      try
        {
          dead_activator = ainfo->activator->_non_existent ();
        }
      catch (const CORBA::Exception&)
        {
          dead_activator = true;
        }

      if (dead_activator)
        {
          // Activator is damaged - reset our info.
          // Client's trying to restart a server on this host will
          // subsequently be told "no activator found for host ..." or
          // some such.
          ainfo->reset ();
        }
    }
  return 0; // This is not a corba call, so a zero should be ok
}

CORBA::Object_ptr
ImR_Locator_i::set_timeout_policy (CORBA::Object_ptr obj, const ACE_Time_Value& to)
{
  CORBA::Object_var ret (CORBA::Object::_duplicate (obj));

  try
    {
      TimeBase::TimeT timeout;
      ORBSVCS_Time::Time_Value_to_TimeT (timeout, to);
      CORBA::Any tmp;
      tmp <<= timeout;

      CORBA::PolicyList policies (1);
      policies.length (1);
      policies[0] = orb_->create_policy (Messaging::RELATIVE_RT_TIMEOUT_POLICY_TYPE, tmp);

      ret = obj->_set_policy_overrides (policies, CORBA::ADD_OVERRIDE);

      policies[0]->destroy ();

      if (CORBA::is_nil (ret.in ()))
        {
          if (this->debug_ > 0)
            {
              ACE_DEBUG ((LM_DEBUG, "ImR: Unable to set timeout policy.\n"));
            }
          ret = CORBA::Object::_duplicate (obj);
        }
    }
  catch (const CORBA::Exception& ex)
    {
      ex._tao_print_exception (
        "ImR_Locator_i::set_timeout_policy ()");
    }

  return ret._retn ();
}

void
ImR_Locator_i::add_or_update_server (const char* server,
                                const ImplementationRepository::StartupOptions &options)
{
  ACE_ASSERT (server != 0);

  if (this->read_only_)
    {
      ACE_DEBUG ((LM_DEBUG, "ImR: Cannot add/update server <%s> due to locked database.\n", server));
      throw CORBA::NO_PERMISSION (
        CORBA::SystemException::_tao_minor_code (
          TAO_IMPLREPO_MINOR_CODE,
          0),
        CORBA::COMPLETED_NO);
    }

  if (debug_ > 0)
    ACE_DEBUG ((LM_DEBUG, "ImR: Add/Update server <%s>.\n", server));

  int limit = options.start_limit;
  if (limit < 0)
    {
      limit = -limit;
    }
  else if (limit == 0)
    {
      limit = 1;
    }

  Server_Info_Ptr info = this->repository_.get_server (server);
  if (info.null ())
    {
      if (this->debug_ > 1)
        ACE_DEBUG ((LM_DEBUG, "ImR: Adding server <%s>.\n", server));

      this->repository_.add_server (server,
                                    options.activator.in (),
                                    options.command_line.in (),
                                    options.environment,
                                    options.working_directory.in (),
                                    options.activation,
                                    limit);
    }
  else
    {
      if (this->debug_ > 1)
        ACE_DEBUG ((LM_DEBUG, "ImR: Updating server <%s>.\n", server));

      info->activator = options.activator.in ();
      info->cmdline = options.command_line.in ();
      info->env_vars = options.environment;
      info->dir = options.working_directory.in ();
      info->activation_mode = options.activation;
      info->start_limit = limit;
      info->start_count = 0;
      int err = this->repository_.update_server (*info);
      ACE_ASSERT (err == 0);
      ACE_UNUSED_ARG (err);
    }

  if (this->debug_ > 1)
    {
      // Note : The info var may be null, so we use options.
      ACE_DEBUG ((LM_DEBUG, "ImR: Server: %s\n"
                  "\tActivator: %s\n"
                  "\tCommand Line: %s\n"
                  "\tWorking Directory: %s\n"
                  "\tActivation: %s\n"
                  "\tStart Limit: %d\n"
                  "\n",
                  server,
                  options.activator.in (),
                  options.command_line.in (),
                  options.working_directory.in (),
                  ImR_Utils::activationModeToString (options.activation).c_str (),
                  limit
                  ));

      for (CORBA::ULong i = 0; i < options.environment.length (); ++i)
        ACE_DEBUG ((LM_DEBUG, "Environment variable %s=%s\n",
                    options.environment[i].name.in (),
                    options.environment[i].value.in ()));
    }
}

void
ImR_Locator_i::remove_server (const char* name)
{
  ACE_ASSERT (name != 0);
  if (this->read_only_)
    {
      ACE_ERROR ((LM_ERROR,
                  "ImR: Can't remove server <%s> due to locked database.\n", name));
      throw CORBA::NO_PERMISSION (
        CORBA::SystemException::_tao_minor_code (
          TAO_IMPLREPO_MINOR_CODE,
          0),
        CORBA::COMPLETED_NO);
    }

  // Note : This will be safe, because any Server_Info_Ptr objects will still
  // be valid, and the actual Server_Info will be destroyed when the last
  // one goes out of scope.

  Server_Info_Ptr info = this->repository_.get_server (name);
  if (! info.null ())
    {
      if (this->repository_.remove_server (name) == 0)
        {
          if (this->debug_ > 1)
            ACE_DEBUG ((LM_DEBUG, "ImR: Removing Server <%s>...\n", name));

          PortableServer::POA_var poa = findPOA (name);
          if (! CORBA::is_nil (poa.in ()))
            {
              bool etherealize = true;
              bool wait = false;
              poa->destroy (etherealize, wait);
            }
          if (this->debug_ > 0)
            ACE_DEBUG ((LM_DEBUG, "ImR: Removed Server <%s>.\n", name));
        }
    }
  else
    {
      ACE_ERROR ((LM_ERROR,
                  "ImR: Can't remove unknown server <%s>.\n", name));
      throw ImplementationRepository::NotFound ();
    }
}

PortableServer::POA_ptr
ImR_Locator_i::findPOA (const char* name)
{
  try
    {
      bool activate_it = false;
      return root_poa_->find_POA (name, activate_it);
    }
  catch (const CORBA::Exception&)
    {// Ignore
    }
  return PortableServer::POA::_nil ();
}

void
ImR_Locator_i::shutdown_server (const char* server)
{
  ACE_ASSERT (server != 0);

  if (this->debug_ > 0)
    ACE_DEBUG ((LM_DEBUG, "ImR: Shutting down server <%s>.\n", server));

  Server_Info_Ptr info = this->repository_.get_server (server);
  if (info.null ())
    {
      ACE_ERROR ((LM_ERROR,
                  "ImR: shutdown_server () Cannot find info for server <%s>\n", server));
      throw ImplementationRepository::NotFound ();
    }

  connect_server (*info);

  if (CORBA::is_nil (info->server.in ()))
    {
      ACE_ERROR ((LM_ERROR,
                  "ImR: shutdown_server () Cannot connect to server <%s>\n", server));
      throw ImplementationRepository::NotFound ();
    }

  try
    {
      CORBA::Object_var obj = set_timeout_policy (info->server.in (), DEFAULT_SHUTDOWN_TIMEOUT);
      ImplementationRepository::ServerObject_var server =
        ImplementationRepository::ServerObject::_unchecked_narrow (obj.in ());
      server->shutdown ();
    }
  catch (const CORBA::TIMEOUT&)
    {
      info->reset ();
      int err = this->repository_.update_server (*info);
      ACE_ASSERT (err == 0);
      ACE_UNUSED_ARG (err);
      // Note : This is a good thing. It means we didn't waste our time waiting for
      // the server to finish shutting down.
      if (this->debug_ > 1)
        {
          ACE_DEBUG ((LM_DEBUG, "ImR: Timeout while waiting for <%s> shutdown.\n", server));
        }
      throw;
    }
  catch (const CORBA::Exception&)
    {
      if (this->debug_ > 1)
        {
          ACE_DEBUG ((LM_DEBUG, "ImR: Exception ignored while shutting down <%s>\n", server));
        }
    }

  // Note : In most cases this has already been done in the server_is_shutting_down ()
  // operation, but it doesn't hurt to update it again.
  info->reset ();

  int err = this->repository_.update_server (*info);
  ACE_ASSERT (err == 0);
  ACE_UNUSED_ARG (err);
}

void
ImR_Locator_i::server_is_running (const char* name,
                                  const char* partial_ior,
                                  ImplementationRepository::ServerObject_ptr server)
{
  ACE_ASSERT (name != 0);
  ACE_ASSERT (partial_ior != 0);
  ACE_ASSERT (! CORBA::is_nil (server));

  if (this->debug_ > 0)
    ACE_DEBUG ((LM_DEBUG, "ImR: Server %s is running at %s.\n", name, partial_ior));

  CORBA::String_var ior = orb_->object_to_string (server);

  if (this->debug_ > 1)
    ACE_DEBUG ((LM_DEBUG, "ImR: Server %s callback at %s.\n", name, ior.in ()));

  Server_Info_Ptr info = this->repository_.get_server (name);
  if (info.null ())
    {
      if (this->debug_ > 0)
        ACE_DEBUG ((LM_DEBUG, "ImR: Auto adding NORMAL server <%s>.\n", name));

      ImplementationRepository::EnvironmentList env (0);
      this->repository_.add_server (name,
                                    "", // no activator
                                    "", // no cmdline
                                    ImplementationRepository::EnvironmentList (),
                                    "", // no working dir
                                    ImplementationRepository::NORMAL,
                                    DEFAULT_START_LIMIT,
                                    partial_ior,
                                    ior.in (),
                                    ImplementationRepository::ServerObject::_nil () // Will connect at first access
                                    );
    }
  else
    {
      if (info->activation_mode != ImplementationRepository::PER_CLIENT) {
        info->ior = ior.in ();
        info->partial_ior = partial_ior;
        info->server = ImplementationRepository::ServerObject::_nil (); // Will connect at first access

        int err = this->repository_.update_server (*info);
        ACE_ASSERT (err == 0);
        ACE_UNUSED_ARG (err);

        waiter_svt_.unblock_one (name, partial_ior, ior.in (), false);
      } else {
        // Note : There's no need to unblock all the waiting request until
        // we know the final status of the server.
        if (info->waiting_clients > 0)
        {
          waiter_svt_.unblock_one (name, partial_ior, ior.in (), true);
        }
        else if (this->debug_ > 1)
        {
          ACE_DEBUG ((LM_DEBUG,
                      ACE_TEXT ("ImR - Ignoring server_is_running due to no ")
                      ACE_TEXT ("waiting PER_CLIENT clients.\n")));
        }
      }
    }
}

void
ImR_Locator_i::server_is_shutting_down (const char* server)
{
  ACE_ASSERT (server != 0);
  Server_Info_Ptr info = this->repository_.get_server (server);
  if (info.null ())
    {
      if (this->debug_ > 1)
        {
          ACE_DEBUG ((LM_DEBUG,
                      "ImR_Locator_i::server_is_shutting_down: Unknown server:%s\n", server));
        }
      return;
    }

  if (this->debug_ > 0)
    ACE_DEBUG ((LM_DEBUG, "ImR: Server <%s> is shutting down.\n", server));

  info->reset ();

  int err = this->repository_.update_server (*info);
  ACE_ASSERT (err == 0);
  ACE_UNUSED_ARG (err);
}

void
ImR_Locator_i::find (const char* server,
                     ImplementationRepository::ServerInformation_out imr_info)
{
  ACE_ASSERT (server != 0);
  ACE_NEW_THROW_EX (imr_info, ImplementationRepository::ServerInformation, CORBA::NO_MEMORY ());

  Server_Info_Ptr info = this->repository_.get_server (server);
  if (! info.null ())
    {
      imr_info = info->createImRServerInfo ();

      if (this->debug_ > 1)
        ACE_DEBUG ((LM_DEBUG, "ImR: Found server %s.\n", server));
    }
  else
    {
      if (debug_ > 1)
        ACE_DEBUG ((LM_DEBUG, "ImR: Cannot find server <%s>\n", server));
    }
}

void
ImR_Locator_i::list (CORBA::ULong how_many,
                     ImplementationRepository::ServerInformationList_out server_list,
                     ImplementationRepository::ServerInformationIterator_out server_iterator)
{
  if (this->debug_ > 1)
    ACE_DEBUG ((LM_DEBUG, "ImR: List servers.\n"));

  // Initialize the out variables, so if we return early, they will
  // not be dangling.
  server_iterator = ImplementationRepository::ServerInformationIterator::_nil ();
  ACE_NEW_THROW_EX (server_list,
                    ImplementationRepository::ServerInformationList (0), CORBA::NO_MEMORY ());

  Locator_Repository::SIMap::ENTRY* entry = 0;
  Locator_Repository::SIMap::ITERATOR it (this->repository_.servers ());

  // Number of servers that will go into the server_list.
  CORBA::ULong n = this->repository_.servers ().current_size ();
  if (how_many > 0 && n > how_many)
    {
      n = how_many;
    }

  server_list->length (n);

  if (this->debug_ > 1)
    ACE_DEBUG ((LM_DEBUG, "ImR_Locator_i::list: Filling ServerList with %d servers\n", n));

  for (CORBA::ULong i = 0; i < n; i++)
    {
      it.next (entry);
      it.advance ();
      ACE_ASSERT (entry != 0);

      Server_Info_Ptr info = entry->int_id_;

      ImplementationRepository::ServerInformation_var imr_info = info->createImRServerInfo ();
      server_list[i] = *imr_info;
    }

  if (this->repository_.servers ().current_size () > n)
    {
      if (this->debug_ > 1)
        ACE_DEBUG ((LM_DEBUG, "ImR_Locator_i::list: Creating ServerInformation Iterator\n"));

      ImR_Iterator* imr_iter = 0;

      ACE_NEW_THROW_EX (imr_iter,
                        ImR_Iterator (n, this->repository_, this->imr_poa_.in ()),
                        CORBA::NO_MEMORY ());

      PortableServer::ServantBase_var tmp (imr_iter);

      try
        {
          PortableServer::ObjectId_var id =
            this->imr_poa_->activate_object (imr_iter);
          CORBA::Object_var obj = this->imr_poa_->id_to_reference (id.in ());
          server_iterator = ImplementationRepository::
            ServerInformationIterator::_unchecked_narrow (obj.in ());
        }
      catch (const CORBA::Exception&)
        {
          throw;
        }
    }
}

Activator_Info_Ptr
ImR_Locator_i::get_activator (const ACE_CString& aname)
{
  Activator_Info_Ptr info = this->repository_.get_activator (aname);
  if (! info.null ())
    {
      this->connect_activator (*info);
    }
  return info;
}

void
ImR_Locator_i::connect_activator (Activator_Info& info)
{
  if (! CORBA::is_nil (info.activator.in ()) || info.ior.length () == 0)
    return;

  try
    {
      CORBA::Object_var obj =
        this->orb_->string_to_object (info.ior.c_str ());

      if (CORBA::is_nil (obj.in ()))
        {
          info.reset ();
          return;
        }

      if (startup_timeout_ > ACE_Time_Value::zero)
        {
          obj = set_timeout_policy (obj.in (), startup_timeout_);
        }

      info.activator =
        ImplementationRepository::Activator::_unchecked_narrow (obj.in ());

      if (CORBA::is_nil (info.activator.in ()))
        {
          info.reset ();
          return;
        }

      if (debug_ > 1)
        ACE_DEBUG ((LM_DEBUG, "ImR: Connected to activator <%s>\n", info.name.c_str ()));
    }
  catch (const CORBA::Exception&)
    {
      info.reset ();
    }
}

void
ImR_Locator_i::auto_start_servers (void)
{
  if (this->repository_.servers ().current_size () == 0)
    return;

  Locator_Repository::SIMap::ENTRY* server_entry;
  Locator_Repository::SIMap::ITERATOR server_iter (this->repository_.servers ());

  // For each of the entries in the Locator_Repository, get the startup
  // information and activate the servers, if they are not already
  // running.
  for (;server_iter.next (server_entry) != 0; server_iter.advance ())
    {
      Server_Info_Ptr info = server_entry->int_id_;
      ACE_ASSERT (! info.null ());

      try
        {
          if (info->activation_mode == ImplementationRepository::AUTO_START
              && info->cmdline.length () > 0)
            {
              this->activate_server_i (*info, true);
            }
        }
      catch (const CORBA::Exception& ex)
        {
          if (this->debug_ > 1)
            {
              ACE_DEBUG ((LM_DEBUG,
                          "ImR: AUTO_START Could not activate <%s>\n",
                          server_entry->ext_id_.c_str ()));
              ex._tao_print_exception ("AUTO_START");
            }
          // Ignore exceptions
        }
    }
}

void
ImR_Locator_i::connect_server (Server_Info& info)
{
  if (! CORBA::is_nil (info.server.in ()))
    {
      return; // already connected
    }

  if (info.ior.length () == 0)
    {
      info.reset ();
      return; // can't connect
    }

  try
    {
      CORBA::Object_var obj = orb_->string_to_object (info.ior.c_str ());

      if (CORBA::is_nil (obj.in ()))
        {
          info.reset ();
          return;
        }

      obj = set_timeout_policy (obj.in (), DEFAULT_SERVER_TIMEOUT);

      info.server =
        ImplementationRepository::ServerObject::_unchecked_narrow (obj.in ());

      if (CORBA::is_nil (info.server.in ()))
        {
          info.reset ();
          return;
        }

      if (debug_ > 1)
        ACE_DEBUG ((LM_DEBUG, "ImR: Connected to server <%s>\n", info.name.c_str ()));
    }
  catch (const CORBA::Exception&)
    {
      info.reset ();
    }
}

bool
ImR_Locator_i::is_alive (Server_Info& info)
{
  const size_t table_size = sizeof (PING_RETRY_SCHEDULE) /
                            sizeof (*PING_RETRY_SCHEDULE);

  for (size_t i = 0; i < table_size; ++i)
    {
      int status = this->is_alive_i (info);
      if (status == 0)
        return false;
      if (status == 1)
        return true;

      // This is evil, but there's not much else we can do for now. We
      // should never reach this code once the ImR Servers are fixed
      // so that they don't lie about server_is_running. Currently,
      // they send this notification during poa creation.  We have to
      // run the orb, because the very thing that may be slowing the
      // aliveness of the servers is the fact that they're trying to
      // register more objects with us.  In practical testing, we
      // never retried the ping more than once, because the second
      // ping always timed out, even if the servers poa manager had
      // not been activated. The only way we saw multiple retries was
      // if we ran the orb on the server before the poa manager was
      // activated.  For this reason, the first retry is immediate,
      // and the orb->run () call is not required. The call will
      // likely timeout, and is_alive will return true.
      if (PING_RETRY_SCHEDULE[i] > 0)
        {
          ACE_Time_Value tv (0, PING_RETRY_SCHEDULE[i] * 1000);
          this->orb_->run (tv);
        }
    }
  if (debug_ > 0)
    {
      ACE_DEBUG ((LM_DEBUG,
                  "ImR: <%s> Ping retry count exceeded. alive=maybe.\n", info.name.c_str ()));
    }
  // We return true here, because the server *might* be alive, it's just not starting in a timely
  // manner. We can't return false, because then we'll just try to start another instance, and the
  // same thing will likely happen.
  info.last_ping = ACE_OS::gettimeofday ();
  return true;
}

int
ImR_Locator_i::is_alive_i (Server_Info& info)
{
  // This is used by the ACE_TRY below when exceptions are turned off.

  if (info.ior.length () == 0 || info.partial_ior.length () == 0)
    {
      if (debug_ > 1)
        {
          ACE_DEBUG ((LM_DEBUG,
                      "ImR: <%s> not running. alive=false.\n", info.name.c_str ()));
        }
      info.last_ping = ACE_Time_Value::zero;
      return 0;
    }

  if (ping_interval_ == ACE_Time_Value::zero)
    {
      if (debug_ > 1)
        {
          ACE_DEBUG ((LM_DEBUG,
                      "ImR: <%s> Ping verification disabled. alive=true.\n", info.name.c_str ()));
        }
      return 1;
    }

  if ((ACE_OS::gettimeofday () - info.last_ping) < ping_interval_)
    {
      if (debug_ > 1)
        {
          ACE_DEBUG ((LM_DEBUG,
                      "ImR: <%s> within ping interval. alive=true.\n", info.name.c_str ()));
        }
      return 1;
    }

  // If we don't have enough information to start the server if it isn't already
  // then we might as well assume it is running. That way the client can get the
  // status directly from the server.
  if (info.cmdline.length () == 0 || ! repository_.has_activator (info.activator))
    {
      if (debug_ > 1)
        {
          ACE_DEBUG ((LM_DEBUG,
                      "ImR: Ping verification skipped. <%s> not startable.\n", info.name.c_str ()));
        }
      return 1;
    }

  connect_server (info);

  if (CORBA::is_nil (info.server.in ()))
    {
      if (debug_ > 1)
        {
          ACE_DEBUG ((LM_DEBUG,
                      "ImR: <%s> Could not connect. alive=false.\n", info.name.c_str ()));
        }
      return 0;
    }

  try
    {
      // Make a copy, in case the info is updated during the ping.
      ImplementationRepository::ServerObject_var server = info.server;

      // This will timeout if it takes too long
      server->ping ();

      if (debug_ > 1)
        {
          ACE_DEBUG ((LM_DEBUG,
                      "ImR: <%s> Ping successful. alive=true\n", info.name.c_str ()));
        }
      info.last_ping = ACE_OS::gettimeofday ();
    }
  catch (const CORBA::TRANSIENT& ex)
    {
      const CORBA::ULong BITS_5_THRU_12_MASK = 0x00000f80;
      switch (ex.minor () & BITS_5_THRU_12_MASK)
        {
        case TAO_INVOCATION_SEND_REQUEST_MINOR_CODE:
          {
            if (debug_ > 1)
              {
                ACE_DEBUG ((LM_DEBUG,
                            "ImR: <%s> Local TRANSIENT. alive=false.\n", info.name.c_str ()));
              }
          }
        info.last_ping = ACE_Time_Value::zero;
        return 0;
        case TAO_POA_DISCARDING:
        case TAO_POA_HOLDING:
          {
            if (debug_ > 1)
              {
                ACE_DEBUG ((LM_DEBUG,
                            "ImR: <%s> Remote TRANSIENT. alive=maybe.\n", info.name.c_str ()));
              }
          }
        return -1; // We keep trying to ping, because returning 1 now, would just lead
        // to clients getting the same exception. If we can't ping after several
        // attempts, then we'll give up and return 1, letting the client worry about it.
        default:
          {
            if (debug_ > 1)
              {
                ACE_DEBUG ((LM_DEBUG,
                            "ImR: <%s> TRANSIENT exception. alive=false.\n", info.name.c_str ()));
              }
            info.last_ping = ACE_Time_Value::zero;
          }
        return 0;
        }
    }
  catch (const CORBA::TIMEOUT&)
    {
      if (debug_ > 1)
        {
          ACE_DEBUG ((LM_DEBUG,
                      "ImR: <%s> Ping timed out. alive=true.\n", info.name.c_str ()));
        }
      return 1; // This is "alive" as far as we're concerned. Presumably the client
      // will have a less stringent timeout policy, or will want to know
      // about the timeout. In any case, we're only guaranteeing that the
      // server is alive, not that it's responsive.
    }
  catch (const CORBA::Exception& ex)
    {
      if (debug_ > 1)
        {
          ACE_DEBUG ((LM_DEBUG, "ImR: <%s> Unexpected Ping exception. alive=false\n", info.name.c_str ()));
          ex._tao_print_exception ("\n");
        }
      info.last_ping = ACE_Time_Value::zero;
      return false;
    }
  return 1;
}

int
ImR_Locator_i::debug () const
{
  return debug_;
}

---