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// $Id$
// ============================================================================
//
// = 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 ());
long function = reinterpret_cast<long> (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);
ssize_t 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;
}
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