/* -*- Mode:C++; c-file-style:"gnu"; indent-tabs-mode:nil; -*- */
/*
* Copyright (c) 2007 INRIA, Gustavo Carneiro
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License version 2 as
* published by the Free Software Foundation;
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA
*
* Authors: Gustavo Carneiro <gjcarneiro@gmail.com>,
* Mathieu Lacage <mathieu.lacage@sophia.inria.fr>
*/
#ifndef OBJECT_H
#define OBJECT_H
#include <stdint.h>
#include <string>
#include "ptr.h"
namespace ns3 {
class TraceResolver;
class CallbackBase;
/**
* \brief a unique identifier for an interface.
*
* Instances of this class can be created only through
* calls to ns3::MakeInterfaceId.
*
* Note: This class is quite similar to COM's UUIDs.
*/
class InterfaceId
{
public:
/**
* \param name the name of the requested interface
* \returns the unique id associated with the requested
* name.
*
* This method cannot fail: it will crash if the input
* name is not a valid interface name.
*/
static InterfaceId LookupByName (std::string name);
/**
* \param iid a unique id
* \returns the parent of the requested id, as registered
* by ns3::MakeInterfaceId.
*
* This method cannot fail: it will crash if the input
* id is not a valid interface id.
*/
static InterfaceId LookupParent (InterfaceId iid);
~InterfaceId ();
private:
InterfaceId (uint16_t iid);
friend InterfaceId MakeInterfaceId (std::string name, const InterfaceId &parent);
friend InterfaceId MakeObjectInterfaceId (void);
friend bool operator == (const InterfaceId &a, const InterfaceId &b);
friend bool operator != (const InterfaceId &a, const InterfaceId &b);
uint16_t m_iid;
};
/**
* \param name of the new InterfaceId to create.
* \param parent the "parent" of the InterfaceId to create.
* \returns a new InterfaceId
* \relates InterfaceId
*
* Every InterfaceId is a child of another InterfaceId. The
* top-most InterfaceId is Object::iid and its parent is
* itself.
*/
InterfaceId
MakeInterfaceId (std::string name, const InterfaceId &parent);
/**
* \brief a base class which provides memory management and object aggregation
*
* Note: This base class is quite similar in spirit to IUnknown in COM or
* BonoboObject in Bonobo: it provides three main methods: Ref, Unref and
* QueryInterface.
*/
class Object
{
public:
static const InterfaceId iid;
Object ();
virtual ~Object ();
/**
* Increment the reference count. This method should not be called
* by user code. Object instances are expected to be used in conjunction
* of the Ptr template which would make calling Ref unecessary and
* dangerous.
*/
inline void Ref (void) const;
/**
* Decrement the reference count. This method should not be called
* by user code. Object instances are expected to be used in conjunction
* of the Ptr template which would make calling Ref unecessary and
* dangerous.
*/
inline void Unref (void) const;
/**
* \param iid the interface requested
* \returns a pointer to the requested interface or zero if it could not be found.
*
*/
template <typename T>
Ptr<T> QueryInterface (InterfaceId iid) const;
/**
* Run the DoDispose methods of this object and all the
* objects aggregated to it.
* After calling this method, the object is expected to be
* totally unusable except for the Ref and Unref methods.
* It is an error to call Dispose twice on the same object
* instance
*/
void Dispose (void);
/**
* \param other another object pointer
*
* This method aggregates the two objects together: after this
* method returns, it becomes possible to call QueryInterface
* on one to get the other, and vice-versa.
*/
void AddInterface (Ptr<Object> other);
void TraceConnect (std::string path, const CallbackBase &cb);
void TraceDisconnect (std::string path, const CallbackBase &cb);
protected:
/**
* \param iid an InterfaceId
*
* Every subclass which defines a new InterfaceId for itself
* should register this InterfaceId by calling this method
* from its constructor.
*/
void SetInterfaceId (InterfaceId iid);
/**
* This method is called by Object::Dispose.
* Subclasses are expected to override this method and chain
* up to their parent's implementation once they are done.
*/
virtual void DoDispose (void);
virtual Ptr<TraceResolver> GetTraceResolver (void) const;
private:
Ptr<Object> DoQueryInterface (InterfaceId iid) const;
bool Check (void) const;
void MaybeDelete (void) const;
mutable uint32_t m_count;
InterfaceId m_iid;
bool m_disposed;
Object *m_next;
};
} // namespace ns3
namespace ns3 {
void
Object::Ref (void) const
{
m_count++;
}
void
Object::Unref (void) const
{
NS_ASSERT (Check ());
m_count--;
if (m_count == 0)
{
MaybeDelete ();
}
}
template <typename T>
Ptr<T>
Object::QueryInterface (InterfaceId iid) const
{
Ptr<Object> found = DoQueryInterface (iid);
if (found != 0)
{
return Ptr<T> (dynamic_cast<T *> (PeekPointer (found)));
}
return 0;
}
} // namespace ns3
#endif /* OBJECT_H */