path: root/ace/SUN_Proactor.cpp

/* -*- C++ -*- */
// $Id$

#include "ace/SUN_Proactor.h"

#if defined (ACE_HAS_AIO_CALLS) && defined (sun)

#if !defined (__ACE_INLINE__)
#include "ace/SUN_Proactor.i"
#endif /* __ACE_INLINE__ */

#include "ace/Task_T.h"
#include "ace/Log_Msg.h"
#include "ace/Object_Manager.h"

ACE_SUN_Proactor::ACE_SUN_Proactor (size_t max_aio_operations)
  : ACE_POSIX_AIOCB_Proactor (max_aio_operations, 
                              ACE_POSIX_Proactor::PROACTOR_SUN),
    condition_ (mutex_)
{
  // To provide correct virtual calls.
  create_notify_manager ();

  // we should start pseudo-asynchronous accept task
  // one per all future acceptors

  this->accept_task_.start ();
}

// Destructor.
ACE_SUN_Proactor::~ACE_SUN_Proactor (void)
{
  // stop asynch accept task
  this->get_asynch_accept_task().stop ();

  // to provide correct virtual calls
  delete_notify_manager ();
}

int
ACE_SUN_Proactor::handle_events (ACE_Time_Value &wait_time)
{
  // Decrement <wait_time> with the amount of time spent in the method
  ACE_Countdown_Time countdown (&wait_time);
  return this->handle_events (wait_time.msec ());
}

int
ACE_SUN_Proactor::handle_events (void)
{
  return this->handle_events (ACE_INFINITE);
}

int ACE_SUN_Proactor::wait_for_start (ACE_Time_Value * abstime)
{
#if defined (ACE_MT_SAFE) && (ACE_MT_SAFE != 0)

  ACE_MT (ACE_GUARD_RETURN (ACE_Thread_Mutex, ace_mon, mutex_, -1));

  if (num_started_aio_ != 0)  // double check
    return 0;

  return condition_.wait (abstime) ;

#else

  return 0;  // or -1 ???

#endif /* ACE_MT_SAFE */
}

int
ACE_SUN_Proactor::handle_events (u_long milli_seconds)
{
  int retval = 0;
  aio_result_t *result = 0;

  if (milli_seconds == ACE_INFINITE)
    {
      if (num_started_aio_ == 0)
        wait_for_start (0);

      result = aiowait (0);
    }
  else
    {
      struct timeval timeout;
      timeout.tv_sec = milli_seconds / 1000;
      timeout.tv_usec = (milli_seconds - (timeout.tv_sec * 1000)) * 1000;

      if (num_started_aio_ == 0)
        {
          ACE_Time_Value tv (timeout);

          tv += ACE_OS::gettimeofday ();
         
          wait_for_start (&tv);
        }
      result = aiowait (&timeout);
    }

  if (ACE_reinterpret_cast (long, result) == 0)
    {
      // timeout, do nothing,
      // we should process "post_completed" queue 
    }
  else if (ACE_reinterpret_cast (long, result) == -1)
    { 
      // Check errno  for  EINVAL,EAGAIN,EINTR ??
      switch (errno)
       {
       case EINTR :     // aiowait() was interrupted by a signal.
       case EINVAL:     // there are no outstanding asynchronous I/O requests.
         break;         // we should process "post_completed" queue 

       default:         // EFAULT
         ACE_ERROR_RETURN ((LM_ERROR,
                       "%N:%l:(%P | %t)::%p \nNumAIO=%d\n",
                       "ACE_SUN_Proactor::handle_events: aiowait failed",
                        num_started_aio_),
                      -1);
       }
    }
  else
    {
      int error_status = 0;
      int return_status = 0;

      ACE_POSIX_Asynch_Result *asynch_result =
        find_completed_aio (result,
                            error_status,
                            return_status);

      if (asynch_result != 0)
        {
          // Call the application code.
          this->application_specific_code (asynch_result,
                                       return_status, // Bytes transferred.
                                       1,             // Success
                                       0,             // No completion key.
                                       error_status); // Error
          retval ++ ;

        }
    }

  // process post_completed results
  retval += this->process_result_queue ();

  return retval > 0 ? 1 : 0 ;

}

ACE_POSIX_Asynch_Result *
ACE_SUN_Proactor::find_completed_aio (aio_result_t *result,
                                       int &error_status,
                                       int &return_status)
{
  ACE_MT (ACE_GUARD_RETURN (ACE_Thread_Mutex, ace_mon, mutex_, 0));

  size_t ai;
  error_status = -1;
  return_status= 0;

  //  we call find_completed_aio always with result != 0
        
  for (ai = 0; ai < aiocb_list_max_size_; ai++)
    if (aiocb_list_[ai] !=0 &&                 //check for non zero
        result == &aiocb_list_[ai]->aio_resultp)
      break;
  
  if (ai >= aiocb_list_max_size_)   // not found 
    return 0;

  error_status = result->aio_errno;
  return_status= result->aio_return;    

  if (error_status == -1)   // should never be
    {
      ACE_ERROR ((LM_ERROR,
                  "%N:%l:(%P | %t)::%p\n",
                  "ACE_SUN_Proactor::find_completed_aio:"
                  "<aio_errno> has failed\n"));

      return_status = 0;  

      // we should notify user, otherwise : 
      // memory leak for result and "hanging" user
      // what was before : 

      // aiocb_list_[ai] = 0;
      // result_list_[ai] = 0;
      // aiocb_list_cur_size_--;
      // return 0;
    }

  switch (error_status)
    {
    case EINPROGRESS :            // should never be
    case AIO_INPROGRESS :         // according to SUN doc
      return 0;   

    case ECANCELED :              // canceled
      return_status = 0;
      break;

    case 0 :                      // no error
      if (return_status == -1)   // return_status should be >= 0
        {
          ACE_ERROR ((LM_ERROR,   
                    "%N:%l:(%P | %t)::%p\n",
                    "ACE_SUN_Proactor::find_completed_aio:"
                    "<aio_return> failed\n"));

          return_status = 0;      // zero bytes transferred
        }
      break;

    default :                     // other errors
      if (return_status == -1)  // normal status for I/O Error
        return_status = 0;        // zero bytes transferred 
      break;
    }

  ACE_POSIX_Asynch_Result *asynch_result = result_list_[ai];

  aiocb_list_[ai] = 0;
  result_list_[ai] = 0;
  aiocb_list_cur_size_--;

  num_started_aio_ --;

  start_deferred_aio ();
  //make attempt to start deferred AIO
  //It is safe as we are protected by mutex_

  return asynch_result;
}

// start_aio has new return codes  
// 0  successful start
// 1  try later, OS queue overflow
// -1 invalid request and other errors

int
ACE_SUN_Proactor::start_aio (ACE_POSIX_Asynch_Result *result)
{
  ACE_TRACE ("ACE_SUN_Proactor::start_aio");

  int ret_val;
  const ACE_TCHAR *ptype;

  // Start IO

  switch (result->aio_lio_opcode)
    {
    case LIO_READ : 
      ptype = "read";
      ret_val = aioread (result->aio_fildes,
                        (char *) result->aio_buf,
                        result->aio_nbytes,
                        result->aio_offset,
                        SEEK_SET,
                        &result->aio_resultp);
      break;

    case LIO_WRITE :
      ptype = "write"; 
      ret_val = aiowrite (result->aio_fildes,
                         (char *) result->aio_buf,
                         result->aio_nbytes,
                         result->aio_offset,
                         SEEK_SET,
                         &result->aio_resultp);
      break;

    default:
      ptype = "?????"; 
      ret_val = -1;
      break;
    }
        
  if (ret_val == 0)
    {
      num_started_aio_ ++ ;
      if (num_started_aio_ == 1)  // wake up condition  
        condition_.broadcast ();
    }
  else // if (ret_val == -1)
    {
      if (errno == EAGAIN)  //try later, it will be deferred AIO
         ret_val = 1 ;
      else
         ACE_ERROR ((LM_ERROR,
                "%N:%l:(%P | %t)::start_aio: aio%s %p\n",
                ptype,
                "queueing failed\n"));
    }

  return ret_val;
}

int
ACE_SUN_Proactor::cancel_aiocb (ACE_POSIX_Asynch_Result *result)
{
  ACE_TRACE ("ACE_SUN_Proactor::cancel_aiocb");
  int rc = ::aiocancel (& result->aio_resultp);
  
  if (rc == 0)    //  AIO_CANCELED
     return 0;

  return 2;
}

int
ACE_SUN_Proactor::cancel_aio (ACE_HANDLE handle)
{
  ACE_TRACE ("ACE_SUN_Proactor::cancel_aio");

  int    num_total     = 0;
  int    num_cancelled = 0;

  {
    ACE_MT (ACE_GUARD_RETURN (ACE_Thread_Mutex, ace_mon, this->mutex_, -1));
          
    size_t ai = 0;

    for (ai = 0; ai < aiocb_list_max_size_; ai++)
      {
        if (result_list_[ai] == 0)    //skip empty slot
          continue ;

        if (result_list_[ai]->aio_fildes != handle)  //skip not our slot
          continue ;

        num_total++ ;  

        ACE_POSIX_Asynch_Result *asynch_result = result_list_[ai];

        int rc_cancel = 0 ;   // let assume canceled 
      
        if (aiocb_list_ [ai] == 0)  //deferred aio
          num_deferred_aiocb_--;
        else      //cancel started aio
          rc_cancel = this->cancel_aiocb (asynch_result);

        if (rc_cancel == 0)
          {  
            num_cancelled ++ ;   

            aiocb_list_[ai] = 0;
            result_list_[ai] = 0;
            aiocb_list_cur_size_--;

            // after aiocancel Sun does not notify us
            // so we should send notification  
            // to save POSIX behavoir.
            // Also we should do this for deffered aio's

            asynch_result->set_error (ECANCELED);
            asynch_result->set_bytes_transferred (0);
            this->putq_result (asynch_result);
          }
      }

  } // release mutex_ 


  if (num_total == 0)
    return 1;  // ALLDONE

  if (num_cancelled == num_total)
    return 0;  // CANCELLED

  return 2; // NOT CANCELLED
}

#endif /* ACE_HAS_AIO_CALLS && sun */