/***********************************************************************
 * 
 *  Copyright (C) 2006 Novell, Inc. All Rights Reserved.
 *
 *  This library is free software; you can redistribute it and/or
 *  modify it under the terms of the GNU Lesser General Public
 *  License as published by the Free Software Foundation; version 2.1
 *  of the License.
 *
 *  This library 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
 *  Library Lesser General Public License for more details.
 *
 *  You should have received a copy of the GNU Lesser General Public
 *  License along with this library; if not, Novell, Inc.
 * 
 *  To contact Novell about this file by physical or electronic mail, 
 *  you may find current contact information at www.novell.com.
 * 
 *  Author: Juan Carlos Luciani <jluciani@novell.com>
 *
 ***********************************************************************/


//===[ Include files ]=====================================================

#include "ipcint.h"
#include "cchannel.h"
#include "clientreq.h"
#include "remoteendpoint.h"
#include <assert.h>     // Ensure that NDEBUG is defined for release builds!

//===[ External data ]=====================================================

//===[ External prototypes ]===============================================

//===[ Manifest constants ]================================================

#define REMOTE_ENDPOINT_SIGNATURE  0x54525653 // SVRT

//===[ Type definitions ]==================================================

//===[ Function prototypes ]===============================================

//===[ Global variables ]==================================================

//===[ Type definitions ]==================================================

//===[ Function prototypes ]===============================================

//===[ Global variables ]==================================================

//
// Object Counters
//
unsigned long  numRemoteEndPointObjects = 0;


//++=======================================================================
RemoteEndPoint::RemoteEndPoint(
   bool multithreaded,
   int maxRpcRetries,
   char *pSocketFileName) :

   m_signature (REMOTE_ENDPOINT_SIGNATURE),
   m_numChannelSubmits (0),
   m_maxRpcRetries (maxRpcRetries)
//
//  Arguments: 
//
//  Returns:   
//
//  Abstract:  
//
//  Notes:
//
// L1
//=======================================================================--
{
   DbgTrace(1, "RemoteEndPoint::RemoteEndPoint- Start, Obj = %08X\n", this);

   // Initialize our mutex
   pthread_mutex_init(&m_mutex, NULL);

   // Set the necessary information in the m_serverUnAddr variable
   m_serverUnAddr.sun_family = AF_UNIX;
   strcpy(m_serverUnAddr.sun_path, pSocketFileName);

   // Set the necessary flags to indicate that DOMAIN sockets
   // should be used for communications.
   m_Use_PF_UNIX = true;
   m_Use_AF_INET = false;

   // Setup the number of channels that we may have based on
   // whether the application is multi-threaded or not.
   if (multithreaded)
      m_numCChannels = MAX_CHANNELS_PER_ENDPOINT;
   else
      m_numCChannels = 1;

   // Instantiate entries in SmartCChannel vector
   try {
      for (int i = 0; i < m_numCChannels; i++)
         m_cchannelVector.push_back(SmartCChannelPointer());
   } catch (...) {
      DbgTrace(0, "RemoteEndPoint::RemoteEndPoint- Exception caught while initializing the cchannelVector\n", 0);
      throw bad_alloc();
   }

   // Increment the object count
   InterlockedIncrement(&numRemoteEndPointObjects);

   DbgTrace(1, "RemoteEndPoint::RemoteEndPoint- End\n", 0);

}  /*-- RemoteEndPoint::RemoteEndPoint() --*/


//++=======================================================================
RemoteEndPoint::RemoteEndPoint(
   bool multithreaded,
   int maxRpcRetries,
   unsigned short int port,
   uint32_t address) :

   m_signature (REMOTE_ENDPOINT_SIGNATURE),
   m_numChannelSubmits (0),
   m_maxRpcRetries (maxRpcRetries)
//
//  Arguments: 
//
//  Returns:   
//
//  Abstract:  
//
//  Notes:
//
// L2
//=======================================================================--
{
   DbgTrace(1, "RemoteEndPoint::RemoteEndPoint- Start, Obj = %08X\n", this);

   // Initialize our mutex
   pthread_mutex_init(&m_mutex, NULL);

   // Set the necessary information in the serverInAddr variable
   m_serverInAddr.sin_family = AF_INET;
   m_serverInAddr.sin_port = htons(port);
   m_serverInAddr.sin_addr.s_addr = htonl(address);

   // Set the necessary flags to indicate that TCP sockets
   // should be used for communications.
   m_Use_AF_INET = true;
   m_Use_PF_UNIX = false;

   // Setup the number of channels that we may have based on
   // whether the application is multi-threaded or not.
   if (multithreaded)
      m_numCChannels = MAX_CHANNELS_PER_ENDPOINT;
   else
      m_numCChannels = 1;

   // Instantiate entries in SmartCChannel vector
   try {
      for (int i = 0; i < m_numCChannels; i++)
         m_cchannelVector.push_back(SmartCChannelPointer());
   } catch (...) {
      DbgTrace(0, "RemoteEndPoint::RemoteEndPoint- Exception caught while initializing the cchannelVector\n", 0);
      throw bad_alloc();
   }

   // Increment the object count
   InterlockedIncrement(&numRemoteEndPointObjects);

   DbgTrace(1, "RemoteEndPoint::RemoteEndPoint- End\n", 0);

}  /*-- RemoteEndPoint::RemoteEndPoint() --*/


//++=======================================================================
RemoteEndPoint::~RemoteEndPoint(void)
//
//  Arguments: 
//
//  Returns:   
//
//  Abstract:  
//
//  Notes:
//
// L2
//=======================================================================--
{
   DbgTrace(1, "RemoteEndPoint::~RemoteEndPoint- Start, Obj = %08X\n", this);

   // Clean up all allocated SmartCChannel objects
   for (int i = 0; i < m_cchannelVector.size(); i++)
   {
      if (m_cchannelVector[i].getPointer() != NULL)
      {
         CChannel *pCChannel = *(m_cchannelVector[i].getPointer());
         pCChannel->closeChannel();
      }
   }
   m_cchannelVector.clear();

   // Decrement the object count
   InterlockedDecrement(&numRemoteEndPointObjects);

   DbgTrace(1, "RemoteEndPoint::~RemoteEndPoint- End\n", 0);

}  /*-- RemoteEndPoint::~RemoteEndPoint() --*/


//++=======================================================================
SmartCChannel*
RemoteEndPoint::getCChannel(void)
//
//  Arguments: 
//
//  Returns:   
//
//  Abstract:  
//
//  Notes:
//
// L2
//=======================================================================--
{
   SmartCChannel *pSmartCChannel = NULL;
   int            channelSelector = (m_numChannelSubmits++) % m_numCChannels;

   DbgTrace(1, "RemoteEndPoint::getCChannel- Start, Obj = %08X\n", this);

#if DEBUG
   assert(m_signature == REMOTE_ENDPOINT_SIGNATURE);
#endif

   // Obtain our mutex
   pthread_mutex_lock(&m_mutex);

   // Check if there is an available and usable channel for the client
   if (m_cchannelVector[channelSelector].getPointer() != NULL
       && (*m_cchannelVector[channelSelector].getPointer())->ok())
   {
      // Use the available channel
      pSmartCChannel = new SmartCChannel(*m_cchannelVector[channelSelector].getPointer());
   }
   else
   {
      // The channel is either unavailable or unusable, clean up
      // the channel if it is indeed unusable.
      if (m_cchannelVector[channelSelector].getPointer() != NULL)
      {
         // Clean up the channel
         CChannel *pCChannel = *m_cchannelVector[channelSelector].getPointer();
         pCChannel->closeChannel();
         delete m_cchannelVector[channelSelector].getPointer();
         m_cchannelVector[channelSelector].setPointer(NULL);
      }

      CChannel *pCChannel;
      try {

         // Use the appropriate server address when instantiating
         // the CChannel object.
         if (m_Use_PF_UNIX)
         {
            // PF_UNIX
            pCChannel = new CChannel(&m_serverUnAddr);
         }
         else
         {
            // Assume AF_INET
            pCChannel = new CChannel(&m_serverInAddr);
         }

         // CChannel object created, now associate a SmartCChannel
         // object with it. It is important to do this to keep
         // the object from being deleted as we initialize it.
         m_cchannelVector[channelSelector].setPointer(new SmartCChannel(pCChannel));

         // Initialize the CChannel
         if (pCChannel->init() == 0)
         {
            // CChannel initialization succeeded, use it to
            // satisfy the caller.
            pSmartCChannel = new SmartCChannel(*m_cchannelVector[channelSelector].getPointer());
         }
         else
         {
            // CChannel initialization failed
            delete m_cchannelVector[channelSelector].getPointer();
            m_cchannelVector[channelSelector].setPointer(NULL);
         }
      }
      catch (...) {
         DbgTrace(0, "getCChannel- Exception caught\n", 0);

         // Try to clean things up just in case
         if (m_cchannelVector[channelSelector].getPointer())
         {
            delete m_cchannelVector[channelSelector].getPointer();
            m_cchannelVector[channelSelector].setPointer(NULL);
         }
         else
         {
            if (pCChannel != NULL)
               delete pCChannel;
         }
      }
   }

   // Release client mutex
   pthread_mutex_unlock(&m_mutex);

   DbgTrace(1, "RemoteEndPoint::getCChannel- End\n", 0);

   return pSmartCChannel;

}  /*-- RemoteEndPoint::getCChannel() --*/


//++=======================================================================
int
RemoteEndPoint::submitReq(
   char *pClientData,
   int clientDataLen,
   char **ppServerData,
   int *pServerDataLen)
//
//  Arguments: 
//
//  Returns:   
//
//  Abstract:  
//
//  Notes:
//
// L2
//=======================================================================--
{
   int   retStatus = -1;

   DbgTrace(1, "RemoteEndPoint::submitReq- Start, Obj = %08X\n", this);

   try {
      SmartCChannel *pSmartCChannel;

      // Perform the following in a loop to deal with abnormal connection terminations
      unsigned long  rpcRetryCount = 0;
      while (rpcRetryCount < m_maxRpcRetries)
      {
         // Get SmartCChannel
         pSmartCChannel = getCChannel();
         if (pSmartCChannel != NULL)
         {
            // Get pointer to channel object
            CChannel *pCChannel = *pSmartCChannel;

            // Allocate a requestId
            uint32_t reqId = pCChannel->allocReqId();

            // Allocate client request object.
            ClientReq clientReq(reqId);

            // Submit the request via the channel
            if (pCChannel->submitReq(reqId,
                                     clientReq,
                                     pClientData,
                                     clientDataLen) == 0)
            {
               // Request submission over the channel succeeded, now
               // wait for the completion of the request.
               clientReq.waitForCompletion(ppServerData,
                                           pServerDataLen);

               // Remove the request from the channel
               pCChannel->removeReq(reqId);

               // Now proceed based on the completion status
               ClientReq::CompletionStatus compStatus = clientReq.completionStatus();
               if (compStatus == ClientReq::SuccessCompletionStatus)
               {
                  // Success
                  retStatus = 0;
               }
            }
            else
            {
               DbgTrace(0, "RemoteEndPoint::submitReq- Request submittion over the channel failed\n", 0);

               // Remove the request from the channel
               pCChannel->removeReq(reqId);
            }

            // Delete the SmartCChannel
            delete pSmartCChannel;
         }
         else
         {
            DbgTrace(0, "RemoteEndPoint::submitReq- Channel unavailable\n", 0);
         }

         // Stop trying if the RPC succeeded
         if (retStatus == 0)
            break;

         // Account for this RPC try
         rpcRetryCount ++;
         DbgTrace(0, "RemoteEndPoint::submitReq- Will attempt to retry RPC, count = %d\n", rpcRetryCount);
      }
   }
   catch(...) {

      DbgTrace(0, "RemoteEndPoint::submitReq- Exception caught\n", 0);
   }

   DbgTrace(1, "RemoteEndPoint::submitReq- End\n", 0);

   return retStatus;

}  /*-- RemoteEndPoint::submitReq() --*/


//=========================================================================
//=========================================================================