// This may look like C, but it's really -*- C++ -*-
// $Id$

// ============================================================================
//
// = LIBRARY
//    TAO
//
// = FILENAME
//    Request.h
//
// = DESCRIPTION
//    Header file for CORBA's Dynamic Invocation Interface "Request"
//    type.
//
// = AUTHOR
//     Copyright 1994-1995 by Sun Microsystems, Inc.
//
// ============================================================================

#ifndef TAO_REQUEST_H
#define TAO_REQUEST_ H

#include "tao/corbafwd.h"
#include "tao/NVList.h"
#include "tao/Environment.h"

class TAO_Export CORBA_Request
{
  // = TITLE
  //   CORBA_Request
  //
  // = DESCRIPTION
  //   Provides a way to create requests and populate it with parameters for
  //   use in the Dynamic Invocation Interface
  //
public:
  CORBA::Object_ptr target (void) const;
  // Return the target of this request.

  const CORBA::Char *operation (void) const;
  // Return the operation name for the request.

  CORBA::NVList_ptr arguments (void);
  // Return the arguments for the request.

  CORBA::NamedValue_ptr result (void);
  // Return the result for the request.

  CORBA::ExceptionList_ptr exceptions (void);
  // Return the exceptions resulting from this request.

  CORBA_Environment *env (void);
  // Return the <Environment> for this request.

  // Argument manipulation helper functions.

  // Arg adders, one for each type of parameter,
  // with and without optional name. Returns
  // reference to Any for insertion using <<=.
  CORBA_Any &add_in_arg (void);
  CORBA_Any &add_in_arg (const char* name);
  CORBA_Any &add_inout_arg (void);
  CORBA_Any &add_inout_arg (const char* name);
  CORBA_Any &add_out_arg (void);
  CORBA_Any &add_out_arg (const char* name);
  // Initialize the return type.
  void set_return_type (CORBA::TypeCode_ptr tc);
  // Returns reference to Any for extraction using >>=.
  CORBA_Any &return_value (void);

  void invoke (void);
  // Perform method resolution and invoke an appropriate method. If
  // the method returns successfully, its result is placed in the
  // result argument specified on <create_request>. The behavior is
  // undefined if this <Request> has already been used with a previous
  // call to <invoke>, <send>, or <send_multiple_requests>.

  void send_oneway (void);
  // Send a oneway request.

  // Pseudo object methods
  static CORBA_Request* _duplicate (CORBA_Request*);
  static CORBA_Request* _nil (void);

  // = Reference counting.
  CORBA::ULong _incr_refcnt (void);
  CORBA::ULong _decr_refcnt (void);

private:
  friend class CORBA_Object;

  // following are not allowed

  CORBA_Request (CORBA::Object_ptr obj,
                 const CORBA::Char *op,
                 CORBA::NVList_ptr args,
                 CORBA::NamedValue_ptr result,
                 CORBA::Flags flags);

  CORBA_Request (CORBA::Object_ptr obj,
                 const CORBA::Char *op);

  ~CORBA_Request (void);

  CORBA::Object_ptr target_;
  // target object

  const CORBA::Char *opname_;
  // operation name

  CORBA::NVList_ptr args_;
  // parameter list

  CORBA::NamedValue_ptr result_;
  // result of the operation

  CORBA::Flags flags_;
  // invocation flags

  CORBA_Environment env_;
  // holds exceptions

  CORBA::ExceptionList exceptions_;
  // list of exceptions raised by the operation

  CORBA::ULong refcount_;
  // reference counting

  ACE_SYNCH_MUTEX refcount_lock_;
  // protect the reference count
};

typedef CORBA_Request* CORBA_Request_ptr;

class TAO_Export CORBA_Request_var
{
  // = TITLE
  //   The T_var class for Request
  //
  // = DESCRIPTION
  //   As any other pseudo object Request must have a T_var class,
  //   the interface an semantics are specified in the CORBA spec.
  //
  // = NOTE
  //   We use CORBA_Request_ptr as the _ptr type instead of
  //   CORBA::Request_ptr, this is an attempt to reduced the cyclic
  //   dependencies in TAO.
  //
public:
  CORBA_Request_var (void);
  CORBA_Request_var (CORBA_Request_ptr);
  CORBA_Request_var (const CORBA_Request_var &);
  ~CORBA_Request_var (void);

  CORBA_Request_var &operator= (CORBA_Request_ptr);
  CORBA_Request_var &operator= (const CORBA_Request_var &);
  CORBA_Request_ptr operator-> (void) const;

  operator const CORBA_Request_ptr &() const;
  operator CORBA_Request_ptr &();
  // in, inout, out, _retn
  CORBA_Request_ptr in (void) const;
  CORBA_Request_ptr &inout (void);
  CORBA_Request_ptr &out (void);
  CORBA_Request_ptr _retn (void);
  CORBA_Request_ptr ptr (void) const;

private:
  CORBA_Request_ptr ptr_;
};

class TAO_Export CORBA_Request_out
{
  // = TITLE
  //   The T_out class for Request
  //
  // = DESCRIPTION
  //   As any other pseudo object Request must have a T_out class,
  //   the interface an semantics are specified in the CORBA spec.
  //
  // = NOTE
  //   We use CORBA_Request_ptr as the _ptr type instead of
  //   CORBA::Request_ptr, this is an attempt to reduced the cyclic
  //   dependencies in TAO.
  //
public:
  CORBA_Request_out (CORBA_Request_ptr &);
  CORBA_Request_out (CORBA_Request_var &);
  CORBA_Request_out (CORBA_Request_out &);
  CORBA_Request_out &operator= (CORBA_Request_out &);
  CORBA_Request_out &operator= (const CORBA_Request_var &);
  CORBA_Request_out &operator= (CORBA_Request_ptr);
  operator CORBA_Request_ptr &();
  CORBA_Request_ptr &ptr (void);
  CORBA_Request_ptr operator-> (void);

private:
  CORBA_Request_ptr &ptr_;
};

#if defined (__ACE_INLINE__)
# include "tao/Request.i"
#endif /* __ACE_INLINE__ */

#endif /* TAO_REQUEST_H */