1 /* 2 * Copyright (C) 2008 The Android Open Source Project 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 * * Redistributions of source code must retain the above copyright 9 * notice, this list of conditions and the following disclaimer. 10 * * Redistributions in binary form must reproduce the above copyright 11 * notice, this list of conditions and the following disclaimer in 12 * the documentation and/or other materials provided with the 13 * distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 16 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 17 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 18 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 19 * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 21 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS 22 * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED 23 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, 24 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT 25 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 */ 28 29 #include <errno.h> 30 31 #include "pthread_accessor.h" 32 33 int pthread_join(pthread_t t, void ** ret_val) { 34 if (t == pthread_self()) { 35 return EDEADLK; 36 } 37 38 pthread_accessor thread(t); 39 if (thread.get() == NULL) { 40 return ESRCH; 41 } 42 43 if (thread->attr.flags & PTHREAD_ATTR_FLAG_DETACHED) { 44 return EINVAL; 45 } 46 47 // Wait for thread death when needed. 48 49 // If the 'join_count' is negative, this is a 'zombie' thread that 50 // is already dead and without stack/TLS. Otherwise, we need to increment 'join-count' 51 // and wait to be signaled 52 int count = thread->join_count; 53 if (count >= 0) { 54 thread->join_count += 1; 55 pthread_cond_wait(&thread->join_cond, &gThreadListLock); 56 count = --thread->join_count; 57 } 58 if (ret_val) { 59 *ret_val = thread->return_value; 60 } 61 62 // Remove thread from thread list when we're the last joiner or when the 63 // thread was already a zombie. 64 if (count <= 0) { 65 _pthread_internal_remove_locked(thread.get()); 66 } 67 return 0; 68 } 69
