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* ptw32_spinlock_check_need_init.c
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* This translation unit implements spin lock primitives.
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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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* Contact Email: rpj@callisto.canberra.edu.au
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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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* 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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* 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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* 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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#include "implement.h"
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ptw32_spinlock_check_need_init (pthread_spinlock_t * lock)
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* The following guarded test is specifically for statically
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* initialised spinlocks (via PTHREAD_SPINLOCK_INITIALIZER).
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* Note that by not providing this synchronisation we risk
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* introducing race conditions into applications which are
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EnterCriticalSection (&ptw32_spinlock_test_init_lock);
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* We got here possibly under race
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* conditions. Check again inside the critical section
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* and only initialise if the spinlock is valid (not been destroyed).
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* If a static spinlock has been destroyed, the application can
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* re-initialise it only by calling pthread_spin_init()
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if (*lock == PTHREAD_SPINLOCK_INITIALIZER)
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result = pthread_spin_init (lock, PTHREAD_PROCESS_PRIVATE);
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else if (*lock == NULL)
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* The spinlock has been destroyed while we were waiting to
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* initialise it, so the operation that caused the
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* auto-initialisation should fail.
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LeaveCriticalSection (&ptw32_spinlock_test_init_lock);