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 1.7 2006/04/06 13:03:09 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 void 50 _thread_exit(const char *fname, int lineno, const char *msg) 51 { 52 53 /* Write an error message to the standard error file descriptor: */ 54 _thread_printf(2, 55 "Fatal error '%s' at line %d in file %s (errno = %d)\n", 56 msg, lineno, fname, errno); 57 58 abort(); 59 } 60 61 /* 62 * Only called when a thread is cancelled. It may be more useful 63 * to call it from pthread_exit() if other ways of asynchronous or 64 * abnormal thread termination can be found. 65 */ 66 void 67 _thr_exit_cleanup(void) 68 { 69 struct pthread *curthread = tls_get_curthread(); 70 71 /* 72 * POSIX states that cancellation/termination of a thread should 73 * not release any visible resources (such as mutexes) and that 74 * it is the applications responsibility. Resources that are 75 * internal to the threads library, including file and fd locks, 76 * are not visible to the application and need to be released. 77 */ 78 /* Unlock all private mutexes: */ 79 _mutex_unlock_private(curthread); 80 81 /* 82 * This still isn't quite correct because we don't account 83 * for held spinlocks (see libc/stdlib/malloc.c). 84 */ 85 } 86 87 void 88 _pthread_exit(void *status) 89 { 90 struct pthread *curthread = tls_get_curthread(); 91 92 /* Check if this thread is already in the process of exiting: */ 93 if ((curthread->cancelflags & THR_CANCEL_EXITING) != 0) { 94 char msg[128]; 95 snprintf(msg, sizeof(msg), "Thread %p has called " 96 "pthread_exit() from a destructor. POSIX 1003.1 " 97 "1996 s16.2.5.2 does not allow this!", curthread); 98 PANIC(msg); 99 } 100 101 /* Flag this thread as exiting. */ 102 atomic_set_int(&curthread->cancelflags, THR_CANCEL_EXITING); 103 104 _thr_exit_cleanup(); 105 106 /* Save the return value: */ 107 curthread->ret = status; 108 while (curthread->cleanup != NULL) { 109 pthread_cleanup_pop(1); 110 } 111 112 /* Check if there is thread specific data: */ 113 if (curthread->specific != NULL) { 114 /* Run the thread-specific data destructors: */ 115 _thread_cleanupspecific(); 116 } 117 118 if (!_thr_isthreaded()) 119 exit(0); 120 121 THREAD_LIST_LOCK(curthread); 122 _thread_active_threads--; 123 if (_thread_active_threads == 0) { 124 THREAD_LIST_UNLOCK(curthread); 125 exit(0); 126 /* Never reach! */ 127 } 128 THR_LOCK(curthread); 129 curthread->state = PS_DEAD; 130 THR_UNLOCK(curthread); 131 curthread->refcount--; 132 if (curthread->tlflags & TLFLAGS_DETACHED) 133 THR_GCLIST_ADD(curthread); 134 THREAD_LIST_UNLOCK(curthread); 135 if (curthread->joiner) 136 _thr_umtx_wake(&curthread->state, INT_MAX); 137 138 /* XXX 139 * All the code is incorrect on DragonFly. 140 * DragonFly has race condition here. it should provide 141 * an interface to tell userland that a thread is now 142 * in kernel, and userland stack can be safely recycled 143 * by userland GC code. 144 */ 145 curthread->terminated = 1; 146 if (SHOULD_REPORT_EVENT(curthread, TD_DEATH)) 147 _thr_report_death(curthread); 148 _exit(0); 149 PANIC("thr_exit() returned"); 150 /* Never reach! */ 151 } 152 153 __strong_reference(_pthread_exit, pthread_exit); 154