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-rw-r--r--pthreads/pthread_rwlock_destroy.c143
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diff --git a/pthreads/pthread_rwlock_destroy.c b/pthreads/pthread_rwlock_destroy.c
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+/*
+ * pthread_rwlock_destroy.c
+ *
+ * Description:
+ * This translation unit implements read/write lock primitives.
+ *
+ * --------------------------------------------------------------------------
+ *
+ * Pthreads-win32 - POSIX Threads Library for Win32
+ * Copyright(C) 1998 John E. Bossom
+ * Copyright(C) 1999,2005 Pthreads-win32 contributors
+ *
+ * Contact Email: rpj@callisto.canberra.edu.au
+ *
+ * The current list of contributors is contained
+ * in the file CONTRIBUTORS included with the source
+ * code distribution. The list can also be seen at the
+ * following World Wide Web location:
+ * http://sources.redhat.com/pthreads-win32/contributors.html
+ *
+ * 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; either
+ * version 2 of the License, or (at your option) any later version.
+ *
+ * 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
+ * Lesser General Public License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public
+ * License along with this library in the file COPYING.LIB;
+ * if not, write to the Free Software Foundation, Inc.,
+ * 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA
+ */
+
+#include <errno.h>
+#include <limits.h>
+
+#include "pthread.h"
+#include "implement.h"
+
+int
+pthread_rwlock_destroy (pthread_rwlock_t * rwlock)
+{
+ pthread_rwlock_t rwl;
+ int result = 0, result1 = 0, result2 = 0;
+
+ if (rwlock == NULL || *rwlock == NULL)
+ {
+ return EINVAL;
+ }
+
+ if (*rwlock != PTHREAD_RWLOCK_INITIALIZER)
+ {
+ rwl = *rwlock;
+
+ if (rwl->nMagic != PTW32_RWLOCK_MAGIC)
+ {
+ return EINVAL;
+ }
+
+ if ((result = pthread_mutex_lock (&(rwl->mtxExclusiveAccess))) != 0)
+ {
+ return result;
+ }
+
+ if ((result =
+ pthread_mutex_lock (&(rwl->mtxSharedAccessCompleted))) != 0)
+ {
+ (void) pthread_mutex_unlock (&(rwl->mtxExclusiveAccess));
+ return result;
+ }
+
+ /*
+ * Check whether any threads own/wait for the lock (wait for ex.access);
+ * report "BUSY" if so.
+ */
+ if (rwl->nExclusiveAccessCount > 0
+ || rwl->nSharedAccessCount > rwl->nCompletedSharedAccessCount)
+ {
+ result = pthread_mutex_unlock (&(rwl->mtxSharedAccessCompleted));
+ result1 = pthread_mutex_unlock (&(rwl->mtxExclusiveAccess));
+ result2 = EBUSY;
+ }
+ else
+ {
+ rwl->nMagic = 0;
+
+ if ((result =
+ pthread_mutex_unlock (&(rwl->mtxSharedAccessCompleted))) != 0)
+ {
+ pthread_mutex_unlock (&rwl->mtxExclusiveAccess);
+ return result;
+ }
+
+ if ((result =
+ pthread_mutex_unlock (&(rwl->mtxExclusiveAccess))) != 0)
+ {
+ return result;
+ }
+
+ *rwlock = NULL; /* Invalidate rwlock before anything else */
+ result = pthread_cond_destroy (&(rwl->cndSharedAccessCompleted));
+ result1 = pthread_mutex_destroy (&(rwl->mtxSharedAccessCompleted));
+ result2 = pthread_mutex_destroy (&(rwl->mtxExclusiveAccess));
+ (void) free (rwl);
+ }
+ }
+ else
+ {
+ /*
+ * See notes in ptw32_rwlock_check_need_init() above also.
+ */
+ EnterCriticalSection (&ptw32_rwlock_test_init_lock);
+
+ /*
+ * Check again.
+ */
+ if (*rwlock == PTHREAD_RWLOCK_INITIALIZER)
+ {
+ /*
+ * This is all we need to do to destroy a statically
+ * initialised rwlock that has not yet been used (initialised).
+ * If we get to here, another thread
+ * waiting to initialise this rwlock will get an EINVAL.
+ */
+ *rwlock = NULL;
+ }
+ else
+ {
+ /*
+ * The rwlock has been initialised while we were waiting
+ * so assume it's in use.
+ */
+ result = EBUSY;
+ }
+
+ LeaveCriticalSection (&ptw32_rwlock_test_init_lock);
+ }
+
+ return ((result != 0) ? result : ((result1 != 0) ? result1 : result2));
+}