TAO/tao/Abstract_Servant_Base.h

   1 // -*- C++ -*-
   2
   3 //=============================================================================
   4 /**
   5  *  @file    Abstract_Servant_Base.h
   6  *
   7  *  This files contains the TAO_Abstract_ServantBase, which is used
   8  *  as a way to decouple the PortableServer from the TAO Core,
   9  *  and make it possible to keep the reference to the servant in
  10  *  the CORBA::Object class.
  11  *
  12  *  @author  Angelo Corsaro <corsaro@cs.wustl.edu>
  13  */
  14 //=============================================================================
  15
  16 #ifndef TAO_ABSTRACT_SERVANT_BASE_H_
  17 #define TAO_ABSTRACT_SERVANT_BASE_H_
  18
  19 #include /**/ "ace/pre.h"
  20
  21 #include /**/ "tao/TAO_Export.h"
  22
  23 #if !defined (ACE_LACKS_PRAGMA_ONCE)
  24 # pragma once
  25 #endif /* ACE_LACKS_PRAGMA_ONCE */
  26
  27 #include "tao/Basic_Types.h"
  28 #include "tao/Collocation_Strategy.h"
  29 #include "tao/CORBA_methods.h"
  30 #include "tao/Pseudo_VarOut_T.h"
  31
  32 TAO_BEGIN_VERSIONED_NAMESPACE_DECL
  33
  34 class TAO_ServerRequest;
  35 class TAO_Stub;
  36 class TAO_Abstract_ServantBase;
  37 class TAO_ServantBase;
  38
  39 namespace CORBA
  40 {
  41   class InterfaceDef;
  42   typedef InterfaceDef *InterfaceDef_ptr;
  43
  44   class Object;
  45   typedef Object *Object_ptr;
  46   typedef TAO_Pseudo_Var_T<Object> Object_var;
  47   typedef TAO_Pseudo_Out_T<Object> Object_out;
  48 }
  49
  50 namespace TAO
  51 {
  52   class Argument;
  53
  54   namespace Portable_Server
  55   {
  56     class Servant_Upcall;
  57   }
  58 }
  59
  60 typedef void (*TAO_Skeleton)(
  61     TAO_ServerRequest &,
  62     TAO::Portable_Server::Servant_Upcall *,
  63     TAO_ServantBase *);
  64
  65 typedef void (*TAO_Collocated_Skeleton)(
  66     TAO_Abstract_ServantBase *,
  67     TAO::Argument **);
  68
  69 class TAO_Export TAO_Abstract_ServantBase
  70 {
  71 public:
  72   /// Destructor
  73   virtual ~TAO_Abstract_ServantBase ();
  74
  75   /// Local implementation of the CORBA::Object::_is_a method.
  76   virtual CORBA::Boolean _is_a (const char* logical_type_id) = 0;
  77
  78 #if (TAO_HAS_MINIMUM_CORBA == 0)
  79   /// Default @c _non_existent: always returns false.
  80   virtual CORBA::Boolean _non_existent () = 0;
  81
  82 #if !defined (CORBA_E_COMPACT) && !defined (CORBA_E_MICRO)
  83   /// Query the Interface Repository.
  84   virtual CORBA::InterfaceDef_ptr _get_interface () = 0;
  85
  86   /// Default @c _get_component: always returns nil.
  87   virtual CORBA::Object_ptr _get_component () = 0;
  88 #endif
  89
  90   /// Default @c _repository_id
  91   virtual char * _repository_id () = 0;
  92 #endif /* TAO_HAS_MINIMUM_CORBA */
  93
  94   //@{
  95   /**
  96    * @name Reference Counting Operations
  97    */
  98   /// Increase reference count by one.
  99   virtual void _add_ref () = 0;
 100
 101   /**
 102    * Decreases reference count by one; if the resulting reference
 103    * count equals zero, _remove_ref invokes delete on its this pointer
 104    * in order to destroy the servant.
 105    */
 106   virtual void _remove_ref () = 0;
 107
 108   /// Returns the current reference count value.
 109   virtual CORBA::ULong _refcount_value () const = 0;
 110   //@}
 111
 112   /// This is an auxiliary method for _this() and _narrow().
 113   virtual TAO_Stub *_create_stub () = 0;
 114
 115   /// Find an operation in the operation table and return a
 116   /// TAO_Skeleton which can be used to make upcalls
 117   virtual int _find (const char *opname,
 118                      TAO_Skeleton &skelfunc,
 119                      const size_t length = 0) = 0;
 120
 121   /// Find an operation in the operation table and return a
 122   /// TAO_Collocated_Skeleton which can be used to make upcalls onto
 123   /// collocated servants.
 124   virtual int _find (const char *opname,
 125                      TAO_Collocated_Skeleton &skelfunc,
 126                      TAO::Collocation_Strategy s,
 127                      const size_t length = 0) = 0;
 128
 129   virtual void _collocated_dispatch (::CORBA::Object_ptr obj,
 130                                      ::CORBA::Object_out forward_obj,
 131                                      bool &is_forwarded,
 132                                      TAO::Argument ** args,
 133                                      int num_args,
 134                                      const char * op,
 135                                      size_t op_len,
 136                                      TAO::Collocation_Strategy strategy) = 0;
 137
 138 protected:
 139   /// Default constructor, only derived classes can be created.
 140   TAO_Abstract_ServantBase ();
 141
 142   /// Copy constructor, protected so no instances can be created.
 143   TAO_Abstract_ServantBase (const TAO_Abstract_ServantBase &);
 144
 145   /// Assignment operator.
 146   TAO_Abstract_ServantBase &operator= (const TAO_Abstract_ServantBase &);
 147
 148   /// Dispatches a request to the object
 149   /**
 150    * Find the operation, cast the type to the most derived type,
 151    * demarshall all the parameters from the request and finally
 152    * invokes the operation, storing the results and out parameters (if
 153    * any) or the exceptions thrown into @a request.
 154    */
 155   virtual void _dispatch (
 156     TAO_ServerRequest &request,
 157     TAO::Portable_Server::Servant_Upcall *servant_upcall) = 0;
 158
 159   /// Get this interface's repository id (TAO specific).
 160   virtual const char *_interface_repository_id () const = 0;
 161 };
 162
 163 TAO_END_VERSIONED_NAMESPACE_DECL
 164
 165 #if defined(__ACE_INLINE__)
 166 #include "tao/Abstract_Servant_Base.inl"
 167 #endif /* __ACE_INLINE__ */
 168
 169 #include /**/ "ace/post.h"
 170
 171 #endif /* TAO_ABSTRACT_SERVANT_BASE_H_ */