1 /* 2 * Copyright (c) 2005, David Xu <davidxu@freebsd.org> 3 * All rights reserved. 4 * 5 * Redistribution and use in source and binary forms, with or without 6 * modification, are permitted provided that the following conditions 7 * are met: 8 * 1. Redistributions of source code must retain the above copyright 9 * notice unmodified, this list of conditions, and the following 10 * disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR 16 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 17 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 18 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, 19 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT 20 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 21 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 22 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 23 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF 24 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 25 * 26 * $FreeBSD$ 27 * 28 */ 29 30 #include "namespace.h" 31 #include <errno.h> 32 #include <pthread.h> 33 #include "un-namespace.h" 34 35 #include "thr_private.h" 36 37 int _pthread_timedjoin_np(pthread_t pthread, void **thread_return, 38 const struct timespec *abstime); 39 static int join_common(pthread_t, void **, const struct timespec *); 40 41 __weak_reference(_pthread_join, pthread_join); 42 __weak_reference(_pthread_timedjoin_np, pthread_timedjoin_np); 43 44 static void backout_join(void *arg) 45 { 46 struct pthread *pthread = (struct pthread *)arg; 47 struct pthread *curthread = _get_curthread(); 48 49 THR_THREAD_LOCK(curthread, pthread); 50 pthread->joiner = NULL; 51 THR_THREAD_UNLOCK(curthread, pthread); 52 } 53 54 int 55 _pthread_join(pthread_t pthread, void **thread_return) 56 { 57 return (join_common(pthread, thread_return, NULL)); 58 } 59 60 int 61 _pthread_timedjoin_np(pthread_t pthread, void **thread_return, 62 const struct timespec *abstime) 63 { 64 if (abstime == NULL || abstime->tv_sec < 0 || abstime->tv_nsec < 0 || 65 abstime->tv_nsec >= 1000000000) 66 return (EINVAL); 67 68 return (join_common(pthread, thread_return, abstime)); 69 } 70 71 /* 72 * Cancellation behavior: 73 * if the thread is canceled, joinee is not recycled. 74 */ 75 static int 76 join_common(pthread_t pthread, void **thread_return, 77 const struct timespec *abstime) 78 { 79 struct pthread *curthread = _get_curthread(); 80 struct timespec ts, ts2, *tsp; 81 void *tmp; 82 long tid; 83 int ret = 0; 84 85 if (pthread == NULL) 86 return (EINVAL); 87 88 if (pthread == curthread) 89 return (EDEADLK); 90 91 if ((ret = _thr_find_thread(curthread, pthread, 1)) != 0) 92 return (ESRCH); 93 94 if ((pthread->flags & THR_FLAGS_DETACHED) != 0) { 95 ret = EINVAL; 96 } else if (pthread->joiner != NULL) { 97 /* Multiple joiners are not supported. */ 98 ret = ENOTSUP; 99 } 100 if (ret) { 101 THR_THREAD_UNLOCK(curthread, pthread); 102 return (ret); 103 } 104 /* Set the running thread to be the joiner: */ 105 pthread->joiner = curthread; 106 107 THR_THREAD_UNLOCK(curthread, pthread); 108 109 THR_CLEANUP_PUSH(curthread, backout_join, pthread); 110 _thr_cancel_enter(curthread); 111 112 tid = pthread->tid; 113 while (pthread->tid != TID_TERMINATED) { 114 _thr_testcancel(curthread); 115 if (abstime != NULL) { 116 clock_gettime(CLOCK_REALTIME, &ts); 117 TIMESPEC_SUB(&ts2, abstime, &ts); 118 if (ts2.tv_sec < 0) { 119 ret = ETIMEDOUT; 120 break; 121 } 122 tsp = &ts2; 123 } else 124 tsp = NULL; 125 ret = _thr_umtx_wait(&pthread->tid, tid, tsp); 126 if (ret == ETIMEDOUT) 127 break; 128 } 129 130 _thr_cancel_leave(curthread, 0); 131 THR_CLEANUP_POP(curthread, 0); 132 133 if (ret == ETIMEDOUT) { 134 THR_THREAD_LOCK(curthread, pthread); 135 pthread->joiner = NULL; 136 THR_THREAD_UNLOCK(curthread, pthread); 137 } else { 138 ret = 0; 139 tmp = pthread->ret; 140 THR_THREAD_LOCK(curthread, pthread); 141 pthread->flags |= THR_FLAGS_DETACHED; 142 pthread->joiner = NULL; 143 _thr_try_gc(curthread, pthread); /* thread lock released */ 144 145 if (thread_return != NULL) 146 *thread_return = tmp; 147 } 148 return (ret); 149 } 150