1 /*
2 * pthread_barrier_destroy.c
3 *
4 * Description:
5 * This translation unit implements barrier primitives.
6 *
7 * --------------------------------------------------------------------------
8 *
9 * Pthreads-win32 - POSIX Threads Library for Win32
10 * Copyright(C) 1998 John E. Bossom
11 * Copyright(C) 1999,2005 Pthreads-win32 contributors
12 *
13 * Contact Email: rpj@callisto.canberra.edu.au
14 *
15 * The current list of contributors is contained
16 * in the file CONTRIBUTORS included with the source
17 * code distribution. The list can also be seen at the
18 * following World Wide Web location:
19 * http://sources.redhat.com/pthreads-win32/contributors.html
20 *
21 * This library is free software; you can redistribute it and/or
22 * modify it under the terms of the GNU Lesser General Public
23 * License as published by the Free Software Foundation; either
24 * version 2 of the License, or (at your option) any later version.
25 *
26 * This library is distributed in the hope that it will be useful,
27 * but WITHOUT ANY WARRANTY; without even the implied warranty of
28 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
29 * Lesser General Public License for more details.
30 *
31 * You should have received a copy of the GNU Lesser General Public
32 * License along with this library in the file COPYING.LIB;
33 * if not, write to the Free Software Foundation, Inc.,
34 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA
35 */
36
37 #include "pthread.h"
38 #include "implement.h"
39
40 int
pthread_barrier_destroy(pthread_barrier_t * barrier)41 pthread_barrier_destroy (pthread_barrier_t * barrier)
42 {
43 int result = 0;
44 pthread_barrier_t b;
45 ptw32_mcs_local_node_t node;
46
47 if (barrier == NULL || *barrier == (pthread_barrier_t) PTW32_OBJECT_INVALID)
48 {
49 return EINVAL;
50 }
51
52 if (0 != ptw32_mcs_lock_try_acquire(&(*barrier)->lock, &node))
53 {
54 return EBUSY;
55 }
56
57 b = *barrier;
58
59 if (b->nCurrentBarrierHeight < b->nInitialBarrierHeight)
60 {
61 result = EBUSY;
62 }
63 else
64 {
65 if (0 == (result = sem_destroy (&(b->semBarrierBreeched))))
66 {
67 *barrier = (pthread_barrier_t) PTW32_OBJECT_INVALID;
68 /*
69 * Release the lock before freeing b.
70 *
71 * FIXME: There may be successors which, when we release the lock,
72 * will be linked into b->lock, which will be corrupted at some
73 * point with undefined results for the application. To fix this
74 * will require changing pthread_barrier_t from a pointer to
75 * pthread_barrier_t_ to an instance. This is a change to the ABI
76 * and will require a major version number increment.
77 */
78 ptw32_mcs_lock_release(&node);
79 (void) free (b);
80 return 0;
81 }
82 else
83 {
84 /*
85 * This should not ever be reached.
86 * Restore the barrier to working condition before returning.
87 */
88 (void) sem_init (&(b->semBarrierBreeched), b->pshared, 0);
89 }
90
91 if (result != 0)
92 {
93 /*
94 * The barrier still exists and is valid
95 * in the event of any error above.
96 */
97 result = EBUSY;
98 }
99 }
100
101 ptw32_mcs_lock_release(&node);
102 return (result);
103 }
104