1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3 *
4 * Copyright (c) 2011 David Chisnall
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 * notice, this list of conditions and the following disclaimer in the
14 * documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 *
28 * $FreeBSD: head/lib/libc/stdlib/quick_exit.c 326193 2017-11-25 17:12:48Z pfg $
29 */
30
31 #include <sys/types.h>
32 #include <machine/atomic.h>
33 #include <stdlib.h>
34 #include <pthread.h>
35
36 /**
37 * Linked list of quick exit handlers. This is simpler than the atexit()
38 * version, because it is not required to support C++ destructors or
39 * DSO-specific cleanups.
40 */
41 struct quick_exit_handler {
42 struct quick_exit_handler *next;
43 void (*cleanup)(void);
44 };
45
46 /**
47 * Lock protecting the handlers list.
48 */
49 static pthread_mutex_t atexit_mutex = PTHREAD_MUTEX_INITIALIZER;
50 /**
51 * Stack of cleanup handlers. These will be invoked in reverse order when
52 */
53 static struct quick_exit_handler *handlers;
54
55 int
at_quick_exit(void (* func)(void))56 at_quick_exit(void (*func)(void))
57 {
58 struct quick_exit_handler *h;
59
60 h = malloc(sizeof(*h));
61
62 if (NULL == h)
63 return (1);
64 h->cleanup = func;
65 pthread_mutex_lock(&atexit_mutex);
66 h->next = handlers;
67 __compiler_membar();
68 handlers = h;
69 pthread_mutex_unlock(&atexit_mutex);
70 return (0);
71 }
72
73 void
quick_exit(int status)74 quick_exit(int status)
75 {
76 struct quick_exit_handler *h;
77
78 /*
79 * XXX: The C++ spec requires us to call std::terminate if there is an
80 * exception here.
81 */
82 for (h = handlers; NULL != h; h = h->next) {
83 __compiler_membar();
84 h->cleanup();
85 }
86 _Exit(status);
87 }
88