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. Neither the name of the author nor the names of any co-contributors
14 * may be used to endorse or promote products derived from this software
15 * without specific prior written permission.
16 *
17 * THIS SOFTWARE IS PROVIDED BY JOHN BIRRELL AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * $FreeBSD: src/lib/libpthread/thread/thr_exit.c,v 1.39 2004/10/23 23:37:54 davidxu Exp $
30 */
31
32 #include "namespace.h"
33 #include <machine/tls.h>
34 #include <errno.h>
35 #include <unistd.h>
36 #include <fcntl.h>
37 #include <stdarg.h>
38 #include <stdio.h>
39 #include <stdlib.h>
40 #include <string.h>
41 #include <pthread.h>
42 #include "un-namespace.h"
43
44 #include "libc_private.h"
45 #include "thr_private.h"
46
47 static void exit_thread(void) __dead2;
48
49 void
_thread_exitf(const char * fname,int lineno,const char * fmt,...)50 _thread_exitf(const char *fname, int lineno, const char *fmt, ...)
51 {
52 va_list ap;
53
54 /* Write an error message to the standard error file descriptor: */
55 _thread_printf(STDERR_FILENO, "Fatal error '");
56
57 va_start(ap, fmt);
58 _thread_vprintf(STDERR_FILENO, fmt, ap);
59 va_end(ap);
60
61 _thread_printf(STDERR_FILENO, "' at line %d in file %s (errno = %d)\n",
62 lineno, fname, errno);
63
64 abort();
65 }
66
67 void
_thread_exit(const char * fname,int lineno,const char * msg)68 _thread_exit(const char *fname, int lineno, const char *msg)
69 {
70 _thread_exitf(fname, lineno, "%s", msg);
71 }
72
73 /*
74 * Only called when a thread is cancelled. It may be more useful
75 * to call it from pthread_exit() if other ways of asynchronous or
76 * abnormal thread termination can be found.
77 */
78 void
_thr_exit_cleanup(void)79 _thr_exit_cleanup(void)
80 {
81 pthread_t curthread = tls_get_curthread();
82
83 /*
84 * POSIX states that cancellation/termination of a thread should
85 * not release any visible resources (such as mutexes) and that
86 * it is the applications responsibility. Resources that are
87 * internal to the threads library, including file and fd locks,
88 * are not visible to the application and need to be released.
89 */
90 /* Unlock all private mutexes: */
91 _mutex_unlock_private(curthread);
92
93 /*
94 * This still isn't quite correct because we don't account
95 * for held spinlocks (see libc/stdlib/malloc.c).
96 */
97 }
98
99 void
_pthread_exit(void * status)100 _pthread_exit(void *status)
101 {
102 pthread_t curthread = tls_get_curthread();
103
104 /* Check if this thread is already in the process of exiting: */
105 if ((curthread->cancelflags & THR_CANCEL_EXITING) != 0) {
106 PANIC("Thread %p has called "
107 "pthread_exit() from a destructor. POSIX 1003.1 "
108 "1996 s16.2.5.2 does not allow this!", curthread);
109 }
110
111 /* Flag this thread as exiting. */
112 atomic_set_int(&curthread->cancelflags, THR_CANCEL_EXITING);
113
114 _thr_exit_cleanup();
115
116 /* Save the return value: */
117 curthread->ret = status;
118 while (curthread->cleanup != NULL) {
119 _pthread_cleanup_pop(1);
120 }
121 /* Call TLS destructors, if any. */
122 _thread_finalize();
123
124 exit_thread();
125 }
126
127 __strong_reference(_pthread_exit, pthread_exit);
128
129 static void
exit_thread(void)130 exit_thread(void)
131 {
132 pthread_t curthread = tls_get_curthread();
133
134 /* Check if there is thread specific data: */
135 if (curthread->specific != NULL) {
136 /* Run the thread-specific data destructors: */
137 _thread_cleanupspecific();
138 }
139
140 if (!_thr_isthreaded())
141 exit(0);
142
143 THREAD_LIST_LOCK(curthread);
144 _thread_active_threads--;
145 if (_thread_active_threads == 0) {
146 THREAD_LIST_UNLOCK(curthread);
147 exit(0);
148 /* Never reach! */
149 }
150 THR_LOCK(curthread);
151 curthread->state = PS_DEAD;
152 THR_UNLOCK(curthread);
153 curthread->refcount--;
154 if (curthread->tlflags & TLFLAGS_DETACHED)
155 THR_GCLIST_ADD(curthread);
156 THREAD_LIST_UNLOCK(curthread);
157 if (curthread->joiner)
158 _thr_umtx_wake(&curthread->state, 0);
159 if (SHOULD_REPORT_EVENT(curthread, TD_DEATH))
160 _thr_report_death(curthread);
161 /* Exit and set terminated to once we're really dead. */
162 extexit(EXTEXIT_SETINT|EXTEXIT_LWP, 1, &curthread->terminated);
163 PANIC("thr_exit() returned");
164 /* Never reach! */
165 }
166