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-rw-r--r--barrier.c432
1 files changed, 34 insertions, 398 deletions
diff --git a/barrier.c b/barrier.c
index e82e9f6..762d742 100644
--- a/barrier.c
+++ b/barrier.c
@@ -4,409 +4,45 @@
* Description:
* This translation unit implements barrier primitives.
*
- * Pthreads-win32 - POSIX Threads Library for Win32
- * Copyright (C) 1998 Ben Elliston and Ross Johnson
- * Copyright (C) 1999,2000,2001 Ross Johnson
+ * --------------------------------------------------------------------------
*
- * Contact Email: rpj@ise.canberra.edu.au
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Library 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
- * Library General Public License for more details.
- *
- * You should have received a copy of the GNU Library General Public
- * License along with this library; if not, write to the Free
- * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
- * MA 02111-1307, USA
+ * Pthreads-win32 - POSIX Threads Library for Win32
+ * Copyright(C) 1998 John E. Bossom
+ * Copyright(C) 1999,2002 Pthreads-win32 contributors
+ *
+ * Contact Email: rpj@ise.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 "pthread.h"
#include "implement.h"
-int
-pthread_barrier_init(pthread_barrier_t * barrier,
- const pthread_barrierattr_t * attr,
- unsigned int count)
-{
- pthread_barrier_t b;
-
- if (barrier == NULL || count == 0)
- {
- return EINVAL;
- }
-
- if (NULL != (b = (pthread_barrier_t) calloc(1, sizeof(*b))))
- {
- b->pshared = (attr != NULL && *attr != NULL
- ? (*attr)->pshared
- : PTHREAD_PROCESS_PRIVATE);
-
- b->nCurrentBarrierHeight = b->nInitialBarrierHeight = count;
- b->iStep = 0;
-
- /*
- * Two semaphores are used in the same way as two stepping
- * stones might be used in crossing a stream. Once all
- * threads are safely on one stone, the other stone can
- * be moved ahead, and the threads can start moving to it.
- * If some threads decide to eat their lunch before moving
- * then the other threads have to wait.
- */
- if (0 == sem_init(&(b->semBarrierBreeched[0]), b->pshared, 0))
- {
- if (0 == sem_init(&(b->semBarrierBreeched[1]), b->pshared, 0))
- {
- *barrier = b;
- return 0;
- }
- (void) sem_destroy(&(b->semBarrierBreeched[0]));
- }
- (void) free(b);
- }
-
- return ENOMEM;
-}
-
-int
-pthread_barrier_destroy(pthread_barrier_t *barrier)
-{
- int result = 0;
- pthread_barrier_t b;
-
- if (barrier == NULL || *barrier == (pthread_barrier_t) PTW32_OBJECT_INVALID)
- {
- return EINVAL;
- }
-
- b = *barrier;
- *barrier = NULL;
-
- if (0 == (result = sem_destroy(&(b->semBarrierBreeched[0]))))
- {
- if (0 == (result = sem_destroy(&(b->semBarrierBreeched[1]))))
- {
- (void) free(b);
- return 0;
- }
- (void) sem_init(&(b->semBarrierBreeched[0]),
- b->pshared,
- 0);
- }
-
- *barrier = b;
- return(result);
-}
-
-
-int
-pthread_barrier_wait(pthread_barrier_t *barrier)
-{
- int result;
- int step;
- pthread_barrier_t b;
-
- if (barrier == NULL || *barrier == (pthread_barrier_t) PTW32_OBJECT_INVALID)
- {
- return EINVAL;
- }
-
- b = *barrier;
- step = b->iStep;
-
- if (0 == InterlockedDecrement((long *) &(b->nCurrentBarrierHeight)))
- {
- /* Must be done before posting the semaphore. */
- b->nCurrentBarrierHeight = b->nInitialBarrierHeight;
-
- /*
- * There is no race condition between the semaphore wait and post
- * because we are using two alternating semas and all threads have
- * entered barrier_wait and checked nCurrentBarrierHeight before this
- * barrier's sema can be posted. Any threads that have not quite
- * entered sem_wait below when the multiple_post has completed
- * will nevertheless continue through the semaphore (barrier)
- * and will not be left stranded.
- */
- result = (b->nInitialBarrierHeight > 1
- ? sem_post_multiple(&(b->semBarrierBreeched[step]),
- b->nInitialBarrierHeight - 1)
- : 0);
- }
- else
- {
- BOOL switchCancelState;
- int oldCancelState;
- pthread_t self = pthread_self();
-
- /*
- * This routine is not a cancelation point, so temporarily
- * prevent sem_wait() from being one.
- * PTHREAD_CANCEL_ASYNCHRONOUS threads can still be canceled.
- */
- switchCancelState = (self->cancelType == PTHREAD_CANCEL_DEFERRED &&
- 0 == pthread_setcancelstate(PTHREAD_CANCEL_DISABLE,
- &oldCancelState));
-
- result = sem_wait(&(b->semBarrierBreeched[step]));
-
- if (switchCancelState)
- {
- (void) pthread_setcancelstate(oldCancelState, NULL);
- }
- }
-
- /*
- * The first thread across will be the PTHREAD_BARRIER_SERIAL_THREAD.
- * This also sets up the alternate semaphore as the next barrier.
- */
- if (0 == result)
- {
- result = ((PTW32_INTERLOCKED_LONG) step ==
- ptw32_interlocked_compare_exchange((PTW32_INTERLOCKED_LPLONG) &(b->iStep),
- (PTW32_INTERLOCKED_LONG) (1L - step),
- (PTW32_INTERLOCKED_LONG) step)
- ? PTHREAD_BARRIER_SERIAL_THREAD
- : 0);
- }
-
- return(result);
-}
-
-
-int
-pthread_barrierattr_init (pthread_barrierattr_t * attr)
- /*
- * ------------------------------------------------------
- * DOCPUBLIC
- * Initializes a barrier attributes object with default
- * attributes.
- *
- * PARAMETERS
- * attr
- * pointer to an instance of pthread_barrierattr_t
- *
- *
- * DESCRIPTION
- * Initializes a barrier attributes object with default
- * attributes.
- *
- * NOTES:
- * 1) Used to define barrier types
- *
- * RESULTS
- * 0 successfully initialized attr,
- * ENOMEM insufficient memory for attr.
- *
- * ------------------------------------------------------
- */
-{
- pthread_barrierattr_t ba;
- int result = 0;
-
- ba = (pthread_barrierattr_t) calloc (1, sizeof (*ba));
-
- if (ba == NULL)
- {
- result = ENOMEM;
- }
- else
- {
- ba->pshared = PTHREAD_PROCESS_PRIVATE;
- }
-
- *attr = ba;
-
- return (result);
-} /* pthread_barrierattr_init */
-
-
-int
-pthread_barrierattr_destroy (pthread_barrierattr_t * attr)
- /*
- * ------------------------------------------------------
- * DOCPUBLIC
- * Destroys a barrier attributes object. The object can
- * no longer be used.
- *
- * PARAMETERS
- * attr
- * pointer to an instance of pthread_barrierattr_t
- *
- *
- * DESCRIPTION
- * Destroys a barrier attributes object. The object can
- * no longer be used.
- *
- * NOTES:
- * 1) Does not affect barrieres created using 'attr'
- *
- * RESULTS
- * 0 successfully released attr,
- * EINVAL 'attr' is invalid.
- *
- * ------------------------------------------------------
- */
-{
- int result = 0;
-
- if (attr == NULL || *attr == NULL)
- {
- result = EINVAL;
- }
- else
- {
- pthread_barrierattr_t ba = *attr;
-
- *attr = NULL;
- free (ba);
- }
-
- return (result);
-} /* pthread_barrierattr_destroy */
-
-
-int
-pthread_barrierattr_getpshared (const pthread_barrierattr_t * attr,
- int *pshared)
- /*
- * ------------------------------------------------------
- * DOCPUBLIC
- * Determine whether barriers created with 'attr' can be
- * shared between processes.
- *
- * PARAMETERS
- * attr
- * pointer to an instance of pthread_barrierattr_t
- *
- * pshared
- * will be set to one of:
- *
- * PTHREAD_PROCESS_SHARED
- * May be shared if in shared memory
- *
- * PTHREAD_PROCESS_PRIVATE
- * Cannot be shared.
- *
- *
- * DESCRIPTION
- * Mutexes creatd with 'attr' can be shared between
- * processes if pthread_barrier_t variable is allocated
- * in memory shared by these processes.
- * NOTES:
- * 1) pshared barriers MUST be allocated in shared
- * memory.
- * 2) The following macro is defined if shared barriers
- * are supported:
- * _POSIX_THREAD_PROCESS_SHARED
- *
- * RESULTS
- * 0 successfully retrieved attribute,
- * EINVAL 'attr' is invalid,
- *
- * ------------------------------------------------------
- */
-{
- int result;
-
- if ((attr != NULL && *attr != NULL) &&
- (pshared != NULL))
- {
- *pshared = (*attr)->pshared;
- result = 0;
- }
- else
- {
- result = EINVAL;
- }
-
- return (result);
-} /* pthread_barrierattr_getpshared */
-
+#include "barrier_init.c"
+#include "barrier_destroy.c"
+#include "barrier_wait.c"
+#include "barrier_attr_init.c"
+#include "barrier_attr_destroy.c"
+#include "barrier_attr_getpshared.c"
+#include "barrier_attr_setpshared.c"
-int
-pthread_barrierattr_setpshared (pthread_barrierattr_t * attr,
- int pshared)
- /*
- * ------------------------------------------------------
- * DOCPUBLIC
- * Barriers created with 'attr' can be shared between
- * processes if pthread_barrier_t variable is allocated
- * in memory shared by these processes.
- *
- * PARAMETERS
- * attr
- * pointer to an instance of pthread_barrierattr_t
- *
- * pshared
- * must be one of:
- *
- * PTHREAD_PROCESS_SHARED
- * May be shared if in shared memory
- *
- * PTHREAD_PROCESS_PRIVATE
- * Cannot be shared.
- *
- * DESCRIPTION
- * Mutexes creatd with 'attr' can be shared between
- * processes if pthread_barrier_t variable is allocated
- * in memory shared by these processes.
- *
- * NOTES:
- * 1) pshared barriers MUST be allocated in shared
- * memory.
- *
- * 2) The following macro is defined if shared barriers
- * are supported:
- * _POSIX_THREAD_PROCESS_SHARED
- *
- * RESULTS
- * 0 successfully set attribute,
- * EINVAL 'attr' or pshared is invalid,
- * ENOSYS PTHREAD_PROCESS_SHARED not supported,
- *
- * ------------------------------------------------------
- */
-{
- int result;
-
- if ((attr != NULL && *attr != NULL) &&
- ((pshared == PTHREAD_PROCESS_SHARED) ||
- (pshared == PTHREAD_PROCESS_PRIVATE)))
- {
- if (pshared == PTHREAD_PROCESS_SHARED)
- {
-
-#if !defined( _POSIX_THREAD_PROCESS_SHARED )
-
- result = ENOSYS;
- pshared = PTHREAD_PROCESS_PRIVATE;
-
-#else
-
- result = 0;
-
-#endif /* _POSIX_THREAD_PROCESS_SHARED */
-
- }
- else
- {
- result = 0;
- }
-
- (*attr)->pshared = pshared;
- }
- else
- {
- result = EINVAL;
- }
-
- return (result);
-
-} /* pthread_barrierattr_setpshared */