1 /*-
2  * Copyright (c) 2017 Juniper Networks.  All rights reserved.
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  *
13  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
14  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
17  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23  * SUCH DAMAGE.
24  *
25  * $FreeBSD: head/lib/libc/stdlib/set_constraint_handler_s.c 322427 2017-08-12 15:18:17Z kib $
26  */
27 
28 #include "namespace.h"
29 #include <sys/types.h>
30 #include <machine/atomic.h>
31 #include <errno.h>
32 #include <pthread.h>
33 #include <stddef.h>
34 #include <stdlib.h>
35 #include <string.h>
36 #include <unistd.h>
37 #include "un-namespace.h"
38 #include "libc_private.h"
39 
40 /*
41  * Rationale recommends allocating new memory each time.
42  */
43 static constraint_handler_t *_ch = NULL;
44 static pthread_mutex_t ch_lock = PTHREAD_MUTEX_INITIALIZER;
45 
46 constraint_handler_t
47 set_constraint_handler_s(constraint_handler_t handler)
48 {
49 	constraint_handler_t *new, *old, ret;
50 
51 	new = malloc(sizeof(constraint_handler_t));
52 	if (new == NULL)
53 		return (NULL);
54 	*new = handler;
55 	if (__isthreaded)
56 		_pthread_mutex_lock(&ch_lock);
57 	old = _ch;
58 	_ch = new;
59 	if (__isthreaded)
60 		_pthread_mutex_unlock(&ch_lock);
61 	if (old == NULL) {
62 		ret = NULL;
63 	} else {
64 		ret = *old;
65 		free(old);
66 	}
67 	return (ret);
68 }
69 
70 void
71 __throw_constraint_handler_s(const char * restrict msg, errno_t error)
72 {
73 	constraint_handler_t ch;
74 
75 	if (__isthreaded)
76 		_pthread_mutex_lock(&ch_lock);
77 	ch = _ch != NULL ? *_ch : NULL;
78 	if (__isthreaded)
79 		_pthread_mutex_unlock(&ch_lock);
80 	if (ch != NULL)
81 		ch(msg, NULL, error);
82 }
83 
84 void
85 abort_handler_s(const char * restrict msg, void * restrict ptr __unused,
86     errno_t error __unused)
87 {
88 	static const char ahs[] = "abort_handler_s : ";
89 
90 	(void) _write(STDERR_FILENO, ahs, sizeof(ahs) - 1);
91 	(void) _write(STDERR_FILENO, msg, strlen(msg));
92 	(void) _write(STDERR_FILENO, "\n", 1);
93 	abort();
94 }
95 
96 void
97 ignore_handler_s(const char * restrict msg __unused,
98     void * restrict ptr __unused, errno_t error __unused)
99 {
100 }
101