1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD 3 * 4 * Copyright (c) 2005, David Xu <davidxu@freebsd.org> 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice unmodified, this list of conditions, and the following 12 * disclaimer. 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. 16 * 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. 27 */ 28 29 #include <sys/cdefs.h> 30 __FBSDID("$FreeBSD$"); 31 32 #include "namespace.h" 33 #include <errno.h> 34 #include <pthread.h> 35 #include "un-namespace.h" 36 37 #include "thr_private.h" 38 39 int _pthread_timedjoin_np(pthread_t pthread, void **thread_return, 40 const struct timespec *abstime); 41 static int join_common(pthread_t, void **, const struct timespec *); 42 43 __weak_reference(_thr_join, pthread_join); 44 __weak_reference(_thr_join, _pthread_join); 45 __weak_reference(_pthread_timedjoin_np, pthread_timedjoin_np); 46 47 static void backout_join(void *arg) 48 { 49 struct pthread *pthread = (struct pthread *)arg; 50 struct pthread *curthread = _get_curthread(); 51 52 THR_THREAD_LOCK(curthread, pthread); 53 pthread->joiner = NULL; 54 THR_THREAD_UNLOCK(curthread, pthread); 55 } 56 57 int 58 _thr_join(pthread_t pthread, void **thread_return) 59 { 60 return (join_common(pthread, thread_return, NULL)); 61 } 62 63 int 64 _pthread_timedjoin_np(pthread_t pthread, void **thread_return, 65 const struct timespec *abstime) 66 { 67 if (abstime == NULL || abstime->tv_sec < 0 || abstime->tv_nsec < 0 || 68 abstime->tv_nsec >= 1000000000) 69 return (EINVAL); 70 71 return (join_common(pthread, thread_return, abstime)); 72 } 73 74 /* 75 * Cancellation behavior: 76 * if the thread is canceled, joinee is not recycled. 77 */ 78 static int 79 join_common(pthread_t pthread, void **thread_return, 80 const struct timespec *abstime) 81 { 82 struct pthread *curthread = _get_curthread(); 83 struct timespec ts, ts2, *tsp; 84 void *tmp; 85 long tid; 86 int ret = 0; 87 88 if (pthread == NULL) 89 return (EINVAL); 90 91 if (pthread == curthread) 92 return (EDEADLK); 93 94 if ((ret = _thr_find_thread(curthread, pthread, 1)) != 0) 95 return (ESRCH); 96 97 if ((pthread->flags & THR_FLAGS_DETACHED) != 0) { 98 ret = EINVAL; 99 } else if (pthread->joiner != NULL) { 100 /* Multiple joiners are not supported. */ 101 ret = ENOTSUP; 102 } 103 if (ret) { 104 THR_THREAD_UNLOCK(curthread, pthread); 105 return (ret); 106 } 107 /* Set the running thread to be the joiner: */ 108 pthread->joiner = curthread; 109 110 THR_THREAD_UNLOCK(curthread, pthread); 111 112 THR_CLEANUP_PUSH(curthread, backout_join, pthread); 113 _thr_cancel_enter(curthread); 114 115 tid = pthread->tid; 116 while (pthread->tid != TID_TERMINATED) { 117 _thr_testcancel(curthread); 118 if (abstime != NULL) { 119 clock_gettime(CLOCK_REALTIME, &ts); 120 TIMESPEC_SUB(&ts2, abstime, &ts); 121 if (ts2.tv_sec < 0) { 122 ret = ETIMEDOUT; 123 break; 124 } 125 tsp = &ts2; 126 } else 127 tsp = NULL; 128 ret = _thr_umtx_wait(&pthread->tid, tid, tsp); 129 if (ret == ETIMEDOUT) 130 break; 131 } 132 133 _thr_cancel_leave(curthread, 0); 134 THR_CLEANUP_POP(curthread, 0); 135 136 if (ret == ETIMEDOUT) { 137 THR_THREAD_LOCK(curthread, pthread); 138 pthread->joiner = NULL; 139 THR_THREAD_UNLOCK(curthread, pthread); 140 } else { 141 ret = 0; 142 tmp = pthread->ret; 143 THR_THREAD_LOCK(curthread, pthread); 144 pthread->flags |= THR_FLAGS_DETACHED; 145 pthread->joiner = NULL; 146 _thr_try_gc(curthread, pthread); /* thread lock released */ 147 148 if (thread_return != NULL) 149 *thread_return = tmp; 150 } 151 return (ret); 152 } 153