thr_join.c revision 56277
1/* 2 * Copyright (c) 1995 John Birrell <jb@cimlogic.com.au>. 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, this list of conditions and the following disclaimer. 10 * 2. Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in the 12 * documentation and/or other materials provided with the distribution. 13 * 3. All advertising materials mentioning features or use of this software 14 * must display the following acknowledgement: 15 * This product includes software developed by John Birrell. 16 * 4. Neither the name of the author nor the names of any co-contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * $FreeBSD: head/lib/libkse/thread/thr_join.c 56277 2000-01-19 07:04:50Z jasone $ 33 */ 34#include <errno.h> 35#ifdef _THREAD_SAFE 36#include <pthread.h> 37#include "pthread_private.h" 38 39int 40pthread_join(pthread_t pthread, void **thread_return) 41{ 42 int ret = 0; 43 pthread_t pthread1 = NULL; 44 45 _thread_enter_cancellation_point(); 46 47 /* Check if the caller has specified an invalid thread: */ 48 if (pthread == NULL || pthread->magic != PTHREAD_MAGIC) { 49 /* Invalid thread: */ 50 _thread_leave_cancellation_point(); 51 return(EINVAL); 52 } 53 54 /* Check if the caller has specified itself: */ 55 if (pthread == _thread_run) { 56 /* Avoid a deadlock condition: */ 57 _thread_leave_cancellation_point(); 58 return(EDEADLK); 59 } 60 61 /* 62 * Find the thread in the list of active threads or in the 63 * list of dead threads: 64 */ 65 if (_find_thread(pthread) == 0 || 66 _find_dead_thread(pthread) == 0) 67 pthread1 = pthread; 68 69 if (pthread1 == NULL) 70 /* Return an error: */ 71 ret = ESRCH; 72 73 /* Check if this thread has been detached: */ 74 else if ((pthread->attr.flags & PTHREAD_DETACHED) != 0) 75 /* Return an error: */ 76 ret = ESRCH; 77 78 /* Check if the thread is not dead: */ 79 else if (pthread->state != PS_DEAD) { 80 /* Clear the interrupted flag: */ 81 _thread_run->interrupted = 0; 82 83 /* 84 * Protect against being context switched out while 85 * adding this thread to the join queue. 86 */ 87 _thread_kern_sig_defer(); 88 89 /* Add the running thread to the join queue: */ 90 TAILQ_INSERT_TAIL(&(pthread->join_queue), _thread_run, qe); 91 92 /* Schedule the next thread: */ 93 _thread_kern_sched_state(PS_JOIN, __FILE__, __LINE__); 94 95 if (_thread_run->interrupted != 0) 96 TAILQ_REMOVE(&(pthread->join_queue), _thread_run, qe); 97 98 _thread_kern_sig_undefer(); 99 100 if (_thread_run->interrupted != 0 && 101 _thread_run->continuation != NULL) 102 _thread_run->continuation(_thread_run); 103 104 /* Check if the thread is not detached: */ 105 if ((pthread->attr.flags & PTHREAD_DETACHED) == 0) { 106 /* Check if the return value is required: */ 107 if (thread_return) 108 /* Return the thread's return value: */ 109 *thread_return = pthread->ret; 110 } 111 else 112 /* Return an error: */ 113 ret = ESRCH; 114 115 /* Check if the return value is required: */ 116 } else if (thread_return != NULL) 117 /* Return the thread's return value: */ 118 *thread_return = pthread->ret; 119 120 _thread_leave_cancellation_point(); 121 122 /* Return the completion status: */ 123 return (ret); 124} 125#endif 126