104 lines
		
	
	
		
			3.3 KiB
		
	
	
	
		
			C
		
	
	
	
			
		
		
	
	
			104 lines
		
	
	
		
			3.3 KiB
		
	
	
	
		
			C
		
	
	
	
/*
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 * pthread_barrier_destroy.c
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 *
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 * Description:
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 * This translation unit implements barrier primitives.
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 *
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 * --------------------------------------------------------------------------
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 *
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 *      Pthreads-win32 - POSIX Threads Library for Win32
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 *      Copyright(C) 1998 John E. Bossom
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 *      Copyright(C) 1999,2005 Pthreads-win32 contributors
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 * 
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 *      Contact Email: rpj@callisto.canberra.edu.au
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 * 
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 *      The current list of contributors is contained
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 *      in the file CONTRIBUTORS included with the source
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 *      code distribution. The list can also be seen at the
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 *      following World Wide Web location:
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 *      http://sources.redhat.com/pthreads-win32/contributors.html
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 * 
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 *      This library is free software; you can redistribute it and/or
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 *      modify it under the terms of the GNU Lesser General Public
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 *      License as published by the Free Software Foundation; either
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 *      version 2 of the License, or (at your option) any later version.
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 * 
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 *      This library is distributed in the hope that it will be useful,
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 *      but WITHOUT ANY WARRANTY; without even the implied warranty of
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 *      MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
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 *      Lesser General Public License for more details.
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 * 
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 *      You should have received a copy of the GNU Lesser General Public
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 *      License along with this library in the file COPYING.LIB;
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 *      if not, write to the Free Software Foundation, Inc.,
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 *      59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
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 */
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#include "pthread.h"
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#include "implement.h"
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int
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pthread_barrier_destroy (pthread_barrier_t * barrier)
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{
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  int result = 0;
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  pthread_barrier_t b;
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  ptw32_mcs_local_node_t node;
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  if (barrier == NULL || *barrier == (pthread_barrier_t) PTW32_OBJECT_INVALID)
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    {
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      return EINVAL;
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    }
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  if (0 != ptw32_mcs_lock_try_acquire(&(*barrier)->lock, &node))
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    {
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      return EBUSY;
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    }
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  b = *barrier;
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  if (b->nCurrentBarrierHeight < b->nInitialBarrierHeight)
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    {
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      result = EBUSY;
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    }
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  else
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	{
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      if (0 == (result = sem_destroy (&(b->semBarrierBreeched))))
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        {
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          *barrier = (pthread_barrier_t) PTW32_OBJECT_INVALID;
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          /*
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           * Release the lock before freeing b.
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           *
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           * FIXME: There may be successors which, when we release the lock,
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           * will be linked into b->lock, which will be corrupted at some
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           * point with undefined results for the application. To fix this
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           * will require changing pthread_barrier_t from a pointer to
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           * pthread_barrier_t_ to an instance. This is a change to the ABI
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           * and will require a major version number increment.
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           */
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          ptw32_mcs_lock_release(&node);
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	  (void) free (b);
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	  return 0;
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	}
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      else
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        {
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          /*
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           * This should not ever be reached.
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           * Restore the barrier to working condition before returning.
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           */
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          (void) sem_init (&(b->semBarrierBreeched), b->pshared, 0);
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        }
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      if (result != 0)
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        {
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          /*
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           * The barrier still exists and is valid
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           * in the event of any error above.
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           */
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          result = EBUSY;
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        }
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    }
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  ptw32_mcs_lock_release(&node);
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  return (result);
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}
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