1 /* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */

     2 /*

     3  * Copyright (c) 2007 INRIA

     4  * All rights reserved.

     5  *

     6  * This program is free software; you can redistribute it and/or modify

     7  * it under the terms of the GNU General Public License version 2 as

     8  * published by the Free Software Foundation;

     9  *

    10  * This program is distributed in the hope that it will be useful,

    11  * but WITHOUT ANY WARRANTY; without even the implied warranty of

    12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the

    13  * GNU General Public License for more details.

    14  *

    15  * You should have received a copy of the GNU General Public License

    16  * along with this program; if not, write to the Free Software

    17  * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA

    18  *

    19  * Author: Mathieu Lacage <mathieu.lacage@sophia.inria.fr>

    20  */

    21 #ifndef INTERFACE_H

    22 #define INTERFACE_H

    23 

    24 #include <string>

    25 #include "ptr.h"

    26 

    27 namespace ns3 {

    28 

    29 class NsUnknownImpl;

    30 

    31 class Iid

    32 {

    33 public:

    34   Iid (std::string name);

    35 private:

    36   friend bool operator == (const Iid &a, const Iid &b);

    37   uint32_t m_iid;

    38 };

    39 

    40 /**

    41  * \brief COM-like IUnknown

    42  *

    43  * This class should be used as a base class for every object which

    44  * wishes to provide a COM-like QueryInterface API. Multiple 

    45  * inheritance where this base class is at the top of the dreaded 

    46  * "diamond" shape is not allowed.

    47  */

    48 class NsUnknown

    49 {

    50 public:

    51   virtual ~NsUnknown ();

    52   void Ref (void) const;

    53   void Unref (void) const;

    54 

    55   /**

    56    * \param iid the NsUnknown id of the requested interface

    57    */

    58   template <typename T>

    59   Ptr<T> QueryInterface (Iid iid) const;

    60 

    61   /**

    62    * \param interface another interface

    63    * 

    64    * Aggregate together the two interfaces. After this call,

    65    * the two interface objects are tied together: each of them

    66    * will be able to perform QI on each other and their lifetimes

    67    * will be found by the same reference count.

    68    */

    69   void AddInterface (Ptr<NsUnknown> interface);

    70 

    71   void Dispose (void);

    72 protected:

    73   /**

    74    * \param iid the Interface Id of the interface defined by a direct subclass

    75    * of this base class

    76    *

    77    * If you are a direct subclass of this class, you _must_ register

    78    * the name of your interface with this constructor.

    79    */

    80   NsUnknown (Iid iid);

    81   /**

    82    * \param iid the Interface id of the interface

    83    * \param a pointer to the interface object

    84    *

    85    * If you are not a direct subclass of the ns3::NsUnknown base class,

    86    * and if you want to register yourself as another accessible interface

    87    * (typically, your subclass has added API), you need to call

    88    * this method to associate an interface id to your interface.

    89    */

    90   void AddSelfInterface (Iid iid, Ptr<NsUnknown> interface);

    91 protected:

    92   /**

    93    * Subclasses who want to handle the "dispose" event should

    94    * override this method. They are also responsible for

    95    * "chaining up" to their parent class' DoDispose method

    96    * once they have done their own "dispose".

    97    */

    98   virtual void DoDispose (void);

    99 private:

   100   friend class NsUnknownImpl;

   101   NsUnknown ();

   102   Ptr<NsUnknown> DoQueryInterface (Iid iid) const;

   103   void RefInternal (void);

   104   void UnrefInternal (void);

   105   NsUnknownImpl *m_impl;

   106   uint32_t m_ref;

   107 };

   108 

   109 }//namespace ns3

   110 

   111 namespace ns3 {

   112 

   113 template <typename T>

   114 Ptr<T>

   115 NsUnknown::QueryInterface (Iid iid) const

   116 {

   117   Ptr<NsUnknown> found = DoQueryInterface (iid);

   118   if (found != 0)

   119     {

   120       return Ptr<T> (dynamic_cast<T *> (PeekPointer (found)));

   121     }

   122   return 0;

   123 }

   124 

   125 

   126 }//namespace ns3

   127 

   128 #endif /* INTERFACE_H */