sessioncontainer.cpp

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//
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/*************************************************************************


  Disclaimer:

    This code and information is provided "as is" without warranty of
    any kind, either expressed or implied, including but not limited to
    the implied warranties of merchantability and/or fitness for a
    particular purpose.

Module Name:

	SessionContainer.cpp

Abstract:
	
	CSessonContainer (IRTCSession to CSession map and storage object) function declarations.

Notes:
	
	The session container is an abstraction allowing us to use any implementation of a map as we see fit.
 	It is used to provide a global storage for the session objects and allow for easy access of the CSession
 	class with use of a IRTCSession pointer (critical for the event handling).  Hopefully this will make the 
 	code cleaner for support of multiple IM sessions, etc..

 	This class provides a central location for storing CSession objects, used here as
 	HANDLEs.  A chained hash table is used for quick lookup, with size presently limited
 	to SESSION_CONTAINER_HASH_SIZE (17) which should be large enough and sufficiently prime
 	 to ensure that each session will get it's own unique bucket (keeping the search speed near O(1)).

 	Important: Presently a remove from the container will call delete on any CSession* 
 		stored inside the container.  Modify later?

**************************************************************************/

#include "SessionContainer.h"
#include "Session.h"

/************************************************************************************************

  CSessionContainer::CSessionContainer()

	  default ctor

 ************************************************************************************************/

CSessionContainer::CSessionContainer()
{		
}


/************************************************************************************************
 
   CSessionContainer::~CSessionContainer()
 
 	Cleanup the container by calling Clear(). (will hangup any open sessions)
 
 *************************************************************************************************/

CSessionContainer::~CSessionContainer()
{
	// shutdown msg called by destructor of the session
	Clear();
}

/************************************************************************************************ 

  Add()
 
	Interface into the CHashTable. return the same session on success and NULL on failure.

 *************************************************************************************************/


HANDLE 
CSessionContainer::Add( 
					   IN HANDLE pSess,
					   IN CSession* pCSession
					   )
{	
	if (m_ht.Add(pSess, pCSession))
		return pSess;
	else
		return NULL;
}

/************************************************************************************************
 
   CSessionContainer::Access()
 
 	Get at the pointer for the CSession object, allows for easier debugging.
 
 	NOTE: Since a pointer is returned, explicitly ASSERT to check for non-existence errors.

 ************************************************************************************************/

CSession* CSessionContainer::Access( 
									IN HANDLE hKey
									) 
{
	CSession* pRetVal = NULL;
	pRetVal = m_ht.Access(hKey);
	ASSERT( pRetVal != NULL );
	
	return pRetVal;
}


/************************************************************************************************

  CSessionContainer::Exist()
 
 	Check for the existence of hKey in the hash table
 
 ************************************************************************************************/

BOOL
CSessionContainer::Exist( 
						 IN HANDLE hKey
						 ) 
{
	return m_ht.Exist( hKey );	
}

/************************************************************************************************
 
   CSessionContainer::Remove()
 	
 	Remove the Session from the container and call it's destructor, removes
 	both the node and the session itself.
 
 ************************************************************************************************/

void 
CSessionContainer::Remove(
						  IN HANDLE hKey						  
						  )
{	
	m_ht.Remove( hKey );
}

/************************************************************************************************
 
   CSessionContainer::Clear()
 
 	Remove all sessions from the container, explicitly call their destructors.
 
 ************************************************************************************************/

void 
CSessionContainer::Clear() 
{
	m_ht.Clear();
}