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 * $FreeBSD$
30 */
31
32#include "namespace.h"
33#include <errno.h>
34#include <unistd.h>
35#include <fcntl.h>
36#include <stdio.h>
37#include <stdlib.h>
38#include <string.h>
39#include <pthread.h>
40#include "un-namespace.h"
41#include "thr_private.h"
42
43void	_pthread_exit(void *status);
44
45__weak_reference(_pthread_exit, pthread_exit);
46
47void
48_thr_exit(const char *fname, int lineno, const char *msg)
49{
50
51	/* Write an error message to the standard error file descriptor: */
52	_thread_printf(2,
53	    "Fatal error '%s' at line %d in file %s (errno = %d)\n",
54	    msg, lineno, fname, errno);
55
56	abort();
57}
58
59/*
60 * Only called when a thread is cancelled.  It may be more useful
61 * to call it from pthread_exit() if other ways of asynchronous or
62 * abnormal thread termination can be found.
63 */
64void
65_thr_exit_cleanup(void)
66{
67	struct pthread	*curthread = _get_curthread();
68
69	/*
70	 * POSIX states that cancellation/termination of a thread should
71	 * not release any visible resources (such as mutexes) and that
72	 * it is the applications responsibility.  Resources that are
73	 * internal to the threads library, including file and fd locks,
74	 * are not visible to the application and need to be released.
75	 */
76	/* Unlock all private mutexes: */
77	_mutex_unlock_private(curthread);
78
79	/*
80	 * This still isn't quite correct because we don't account
81	 * for held spinlocks (see libc/stdlib/malloc.c).
82	 */
83}
84
85void
86_pthread_exit(void *status)
87{
88	struct pthread *curthread = _get_curthread();
89	kse_critical_t crit;
90	struct kse *curkse;
91
92	/* Check if this thread is already in the process of exiting: */
93	if ((curthread->flags & THR_FLAGS_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	/*
102	 * Flag this thread as exiting.  Threads should now be prevented
103	 * from joining to this thread.
104	 */
105	THR_SCHED_LOCK(curthread, curthread);
106	curthread->flags |= THR_FLAGS_EXITING;
107	THR_SCHED_UNLOCK(curthread, curthread);
108
109	/*
110	 * To avoid signal-lost problem, if signals had already been
111	 * delivered to us, handle it. we have already set EXITING flag
112	 * so no new signals should be delivered to us.
113	 * XXX this is not enough if signal was delivered just before
114	 * thread called sigprocmask and masked it! in this case, we
115	 * might have to re-post the signal by kill() if the signal
116	 * is targeting process (not for a specified thread).
117	 * Kernel has same signal-lost problem, a signal may be delivered
118	 * to a thread which is on the way to call sigprocmask or thr_exit()!
119	 */
120	if (curthread->check_pending)
121		_thr_sig_check_pending(curthread);
122	/* Save the return value: */
123	curthread->ret = status;
124	while (curthread->cleanup != NULL) {
125		_pthread_cleanup_pop(1);
126	}
127	if (curthread->attr.cleanup_attr != NULL) {
128		curthread->attr.cleanup_attr(curthread->attr.arg_attr);
129	}
130	/* Check if there is thread specific data: */
131	if (curthread->specific != NULL) {
132		/* Run the thread-specific data destructors: */
133		_thread_cleanupspecific();
134	}
135	if (!_kse_isthreaded())
136		exit(0);
137	crit = _kse_critical_enter();
138	curkse = _get_curkse();
139	KSE_LOCK_ACQUIRE(curkse, &_thread_list_lock);
140	/* Use thread_list_lock */
141	_thread_active_threads--;
142	if ((_thread_scope_system <= 0 && _thread_active_threads == 1) ||
143	    (_thread_scope_system > 0 && _thread_active_threads == 0)) {
144		KSE_LOCK_RELEASE(curkse, &_thread_list_lock);
145		_kse_critical_leave(crit);
146		exit(0);
147		/* Never reach! */
148	}
149	KSE_LOCK_RELEASE(curkse, &_thread_list_lock);
150
151	/* This thread will never be re-scheduled. */
152	KSE_LOCK(curkse);
153	THR_SET_STATE(curthread, PS_DEAD);
154	_thr_sched_switch_unlocked(curthread);
155	/* Never reach! */
156
157	/* This point should not be reached. */
158	PANIC("Dead thread has resumed");
159}
160