2 * SPDX-License-Identifier: BSD-2-Clause
4 * Copyright (c) 2005, David Xu <davidxu@freebsd.org>
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
10 * 1. Redistributions of source code must retain the above copyright
11 * notice unmodified, this list of conditions, and the following
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
32 #include "namespace.h"
35 #include "un-namespace.h"
37 #include "thr_private.h"
39 int _pthread_peekjoin_np(pthread_t pthread, void **thread_return);
40 int _pthread_timedjoin_np(pthread_t pthread, void **thread_return,
41 const struct timespec *abstime);
42 static int join_common(pthread_t, void **, const struct timespec *, bool peek);
44 __weak_reference(_thr_join, pthread_join);
45 __weak_reference(_thr_join, _pthread_join);
46 __weak_reference(_pthread_timedjoin_np, pthread_timedjoin_np);
47 __weak_reference(_pthread_peekjoin_np, pthread_peekjoin_np);
49 static void backout_join(void *arg)
51 struct pthread *pthread = (struct pthread *)arg;
52 struct pthread *curthread = _get_curthread();
54 THR_THREAD_LOCK(curthread, pthread);
55 pthread->joiner = NULL;
56 THR_THREAD_UNLOCK(curthread, pthread);
60 _thr_join(pthread_t pthread, void **thread_return)
62 return (join_common(pthread, thread_return, NULL, false));
66 _pthread_timedjoin_np(pthread_t pthread, void **thread_return,
67 const struct timespec *abstime)
69 if (abstime == NULL || abstime->tv_sec < 0 || abstime->tv_nsec < 0 ||
70 abstime->tv_nsec >= 1000000000)
73 return (join_common(pthread, thread_return, abstime, false));
77 _pthread_peekjoin_np(pthread_t pthread, void **thread_return)
79 return (join_common(pthread, thread_return, NULL, true));
83 * Cancellation behavior:
84 * if the thread is canceled, joinee is not recycled.
87 join_common(pthread_t pthread, void **thread_return,
88 const struct timespec *abstime, bool peek)
90 struct pthread *curthread = _get_curthread();
91 struct timespec ts, ts2, *tsp;
99 if (pthread == curthread)
102 if ((ret = _thr_find_thread(curthread, pthread, 1)) != 0)
105 if ((pthread->flags & THR_FLAGS_DETACHED) != 0) {
107 } else if (pthread->joiner != NULL) {
108 /* Multiple joiners are not supported. */
112 THR_THREAD_UNLOCK(curthread, pthread);
116 /* Only peek into status, do not gc the thread. */
118 if (pthread->tid != TID_TERMINATED)
120 else if (thread_return != NULL)
121 *thread_return = pthread->ret;
122 THR_THREAD_UNLOCK(curthread, pthread);
126 /* Set the running thread to be the joiner: */
127 pthread->joiner = curthread;
129 THR_THREAD_UNLOCK(curthread, pthread);
131 THR_CLEANUP_PUSH(curthread, backout_join, pthread);
132 _thr_cancel_enter(curthread);
135 while (pthread->tid != TID_TERMINATED) {
136 _thr_testcancel(curthread);
137 if (abstime != NULL) {
138 clock_gettime(CLOCK_REALTIME, &ts);
139 TIMESPEC_SUB(&ts2, abstime, &ts);
140 if (ts2.tv_sec < 0) {
147 ret = _thr_umtx_wait(&pthread->tid, tid, tsp);
148 if (ret == ETIMEDOUT)
152 _thr_cancel_leave(curthread, 0);
153 THR_CLEANUP_POP(curthread, 0);
155 if (ret == ETIMEDOUT) {
156 THR_THREAD_LOCK(curthread, pthread);
157 pthread->joiner = NULL;
158 THR_THREAD_UNLOCK(curthread, pthread);
162 THR_THREAD_LOCK(curthread, pthread);
163 pthread->flags |= THR_FLAGS_DETACHED;
164 pthread->joiner = NULL;
165 _thr_try_gc(curthread, pthread); /* thread lock released */
167 if (thread_return != NULL)
168 *thread_return = tmp;