1 files changed, 180 insertions, 0 deletions
diff --git a/TAO/examples/POA/On_Demand_Loading/Servant_Manager.cpp b/TAO/examples/POA/On_Demand_Loading/Servant_Manager.cpp
new file mode 100644
index 00000000000..7928d3143f9
--- /dev/null
+++ b/TAO/examples/POA/On_Demand_Loading/Servant_Manager.cpp
@@ -0,0 +1,180 @@
+// $Id$
+
+// ============================================================================
+//
+// = LIBRARY
+//     TAO/examples/POA/On_Demand_Loading
+//
+// = FILENAME
+//     Servant_Manager.cpp
+//
+// = DESCRIPTION
+//     Implementation of the helper class for the ServantActivator_i
+//     and the ServantLocator_i.
+//
+// = AUTHOR
+//     Kirthika Parameswaran <kirthika@cs.wustl.edu>
+//
+// ============================================================================
+
+#include "Servant_Manager.h"
+#include "tao/debug.h"
+
+ACE_RCSID(On_Demand_Activation, Servant_Manager, "$Id$")
+
+  // Initialization.
+  ServantManager_i::ServantManager_i (CORBA::ORB_ptr orb)
+    : orb_ (CORBA::ORB::_duplicate (orb))
+{
+}
+
+// Destruction.
+ServantManager_i::~ServantManager_i (void)
+{
+}
+
+// This method loads the dynamically linked DLL which is the servant
+// and returns the servant object which is then used for other
+// operations in the DLL.
+
+PortableServer::Servant
+ServantManager_i::obtain_servant (const char *str,
+                                  PortableServer::POA_ptr poa)
+{
+  // The string format is <dllname:factory_function> that must be
+  // parsed.
+  this->parse_string (str);
+
+  // Create the DLL object.
+  ACE_DLL *dll;
+
+  ACE_NEW_RETURN (dll,
+                  ACE_DLL,
+                  0);
+
+  // Obtain the ObjectId from the string argument.
+
+  PortableServer::ObjectId_var oid =
+    PortableServer::string_to_ObjectId (str);
+
+  if (TAO_debug_level > 0)
+    ACE_DEBUG ((LM_DEBUG,
+                "before bind\n"));
+  // Make an HASH_MAP entry by binding the object_id and the DLL
+  // object associated with it together.
+  if (this->servant_map_.bind (oid.in (),
+                               dll) == -1)
+    ACE_ERROR_RETURN ((LM_ERROR,
+                       "%p\n",
+                       "Bind failed"),
+                      0);
+  // Now that the dll name is available we open the dll.
+  if (dll->open (dllname_.c_str ()) == -1)
+    ACE_ERROR_RETURN ((LM_ERROR,
+                       "%p",
+                       dll->error ()),
+                      0);
+
+  // The next step is to obtain the symbol for the function that will
+  // create the servant object and return it.
+
+  // Cannot go from void* to function pointer directly. Cast the void*
+  // to long first.
+  void *symbol = dll->symbol (create_symbol_.c_str ());
+  intptr_t function = reinterpret_cast<intptr_t> (symbol);
+
+  SERVANT_FACTORY servant_creator =
+    reinterpret_cast<SERVANT_FACTORY> (function);
+
+  // Checking whether it is possible to create the servant.
+  if (servant_creator == 0)
+    ACE_ERROR_RETURN ((LM_ERROR,
+                       "%p",
+                       dll->error ()),
+                      0);
+
+  // Now create and return the servant using the <servant_creator>
+  // factory function.
+  return (*servant_creator) (this->orb_.in (),
+                             poa);
+}
+
+// The objectID is in a format of dllname:factory_function which has
+// to be parsed and separated into tokens to be used.
+
+void
+ServantManager_i::parse_string (const char *s)
+{
+  // The format of the objectid is <dll:factory_function>.  This
+  // string is parsed to obtain the dll name and the function name
+  // which will create trhe servant and return it to us.
+
+  ACE_CString str (s);
+
+  ACE_CString::size_type index = str.find (':');
+  // On error, npos is returned.
+  if (index == ACE_CString::npos)
+    ACE_ERROR ((LM_ERROR,
+                "Required character absent!\n"));
+
+  // The index gives us the location which is equivalent to the size
+  // of the dllname_ string.
+  this->dllname_ = str.substr (0, index);
+
+  // Obtain the substring from the offset which is one greater than
+  // the location of ':'.
+  this->create_symbol_ = str.substr (index + 1);
+
+  if (TAO_debug_level > 0)
+    ACE_DEBUG ((LM_DEBUG,
+                "the servant dll:%s\n the factory_function:%s\n ",
+                this->dllname_.c_str (),
+                this->create_symbol_.c_str ()));
+}
+
+// This method returns an ObjectId when given a DLL name and the
+// factory function to be invoked in the DLL.  The format of the
+// ObjectId is libname:factory_function.
+
+PortableServer::ObjectId_var
+ServantManager_i::create_dll_object_id (const char *libname,
+                                        const char *factory_function)
+{
+  ACE_CString format_string = libname;
+  format_string += ":";
+  format_string += factory_function;
+
+  ACE_DEBUG ((LM_DEBUG,
+              "format-string is %s\n",
+              format_string.c_str ()));
+  // The object ID is created.
+  PortableServer::ObjectId_var oid =
+    PortableServer::string_to_ObjectId (format_string.c_str ());
+  return oid;
+}
+
+// This method destroys the servant and its caretaking DLL object.
+
+void
+ServantManager_i::destroy_servant (PortableServer::Servant servant,
+                                   const PortableServer::ObjectId &oid)
+{
+  // The servant is destroyed.
+  delete servant;
+
+  // Since the servant is no more the DLL object associated with it
+  // has to be destroyed too.
+
+  ACE_DLL *dll = 0;
+
+  // Since the servant is no more the DLL object associated with it
+  // has to be destroyed too.
+
+  if (this->servant_map_.unbind (oid,
+                                 dll) == -1)
+    ACE_ERROR ((LM_ERROR,
+                "%p\n",
+                "Unbind failed!\n"));
+  delete dll;
+}
+