1 /* 2 * Copyright (c) 1995-1998 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: src/lib/libpthread/thread/thr_exit.c,v 1.39 2004/10/23 23:37:54 davidxu Exp $ 33 * $DragonFly: src/lib/libthread_xu/thread/thr_exit.c,v 1.4 2006/03/12 11:28:06 davidxu Exp $ 34 */ 35 36 #include <machine/tls.h> 37 38 #include <errno.h> 39 #include <unistd.h> 40 #include <fcntl.h> 41 #include <stdio.h> 42 #include <stdlib.h> 43 #include <string.h> 44 #include <pthread.h> 45 #include "thr_private.h" 46 47 void _pthread_exit(void *status); 48 49 __weak_reference(_pthread_exit, pthread_exit); 50 51 void 52 _thread_exit(char *fname, int lineno, char *msg) 53 { 54 55 /* Write an error message to the standard error file descriptor: */ 56 _thread_printf(2, 57 "Fatal error '%s' at line %d in file %s (errno = %d)\n", 58 msg, lineno, fname, errno); 59 60 abort(); 61 } 62 63 /* 64 * Only called when a thread is cancelled. It may be more useful 65 * to call it from pthread_exit() if other ways of asynchronous or 66 * abnormal thread termination can be found. 67 */ 68 void 69 _thr_exit_cleanup(void) 70 { 71 struct pthread *curthread = tls_get_curthread(); 72 73 /* 74 * POSIX states that cancellation/termination of a thread should 75 * not release any visible resources (such as mutexes) and that 76 * it is the applications responsibility. Resources that are 77 * internal to the threads library, including file and fd locks, 78 * are not visible to the application and need to be released. 79 */ 80 /* Unlock all private mutexes: */ 81 _mutex_unlock_private(curthread); 82 83 /* 84 * This still isn't quite correct because we don't account 85 * for held spinlocks (see libc/stdlib/malloc.c). 86 */ 87 } 88 89 void 90 _pthread_exit(void *status) 91 { 92 struct pthread *curthread = tls_get_curthread(); 93 94 /* Check if this thread is already in the process of exiting: */ 95 if ((curthread->cancelflags & THR_CANCEL_EXITING) != 0) { 96 char msg[128]; 97 snprintf(msg, sizeof(msg), "Thread %p has called " 98 "pthread_exit() from a destructor. POSIX 1003.1 " 99 "1996 s16.2.5.2 does not allow this!", curthread); 100 PANIC(msg); 101 } 102 103 /* Flag this thread as exiting. */ 104 atomic_set_int(&curthread->cancelflags, THR_CANCEL_EXITING); 105 106 _thr_exit_cleanup(); 107 108 /* Save the return value: */ 109 curthread->ret = status; 110 while (curthread->cleanup != NULL) { 111 pthread_cleanup_pop(1); 112 } 113 if (curthread->attr.cleanup_attr != NULL) { 114 curthread->attr.cleanup_attr(curthread->attr.arg_attr); 115 } 116 /* Check if there is thread specific data: */ 117 if (curthread->specific != NULL) { 118 /* Run the thread-specific data destructors: */ 119 _thread_cleanupspecific(); 120 } 121 122 if (!_thr_isthreaded()) 123 exit(0); 124 125 THREAD_LIST_LOCK(curthread); 126 _thread_active_threads--; 127 if (_thread_active_threads == 0) { 128 THREAD_LIST_UNLOCK(curthread); 129 exit(0); 130 /* Never reach! */ 131 } 132 THR_LOCK(curthread); 133 curthread->state = PS_DEAD; 134 THR_UNLOCK(curthread); 135 curthread->refcount--; 136 if (curthread->tlflags & TLFLAGS_DETACHED) 137 THR_GCLIST_ADD(curthread); 138 THREAD_LIST_UNLOCK(curthread); 139 if (curthread->joiner) 140 _thr_umtx_wake(&curthread->state, INT_MAX); 141 142 /* XXX 143 * All the code is incorrect on DragonFly. 144 * DragonFly has race condition here. it should provide 145 * an interface to tell userland that a thread is now 146 * in kernel, and userland stack can be safely recycled 147 * by userland GC code. 148 */ 149 curthread->terminated = 1; 150 if (SHOULD_REPORT_EVENT(curthread, TD_DEATH)) 151 _thr_report_death(curthread); 152 _exit(0); 153 PANIC("thr_exit() returned"); 154 /* Never reach! */ 155 } 156