1 /*-
2  * Copyright (c) 2011 David Chisnall
3  * Copyright (c) 2015 embedded brains GmbH
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
16  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
19  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25  * SUCH DAMAGE.
26  *
27  * $FreeBSD$
28  */
29 
30 #include <stdlib.h>
31 #include <unistd.h>
32 #include <sys/lock.h>
33 
34 /**
35  * Linked list of quick exit handlers.  This is simpler than the atexit()
36  * version, because it is not required to support C++ destructors or
37  * DSO-specific cleanups.
38  */
39 struct quick_exit_handler {
40 	struct quick_exit_handler *next;
41 	void (*cleanup)(void);
42 };
43 
44 /**
45  * Lock protecting the handlers list.
46  */
47 #ifndef __SINGLE_THREAD__
48 __LOCK_INIT(static, __at_quick_exit_mutex);
49 #endif
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 #ifndef __SINGLE_THREAD__
66 	__lock_acquire(__at_quick_exit_mutex);
67 #endif
68 	h->next = handlers;
69 	handlers = h;
70 #ifndef __SINGLE_THREAD__
71 	__lock_release(__at_quick_exit_mutex);
72 #endif
73 	return (0);
74 }
75 
76 void
quick_exit(int status)77 quick_exit(int status)
78 {
79 	struct quick_exit_handler *h;
80 
81 	/*
82 	 * XXX: The C++ spec requires us to call std::terminate if there is an
83 	 * exception here.
84 	 */
85 	for (h = handlers; NULL != h; h = h->next)
86 		h->cleanup();
87 	_exit(status);
88 }
89