1 /*	$NetBSD: sigstackalign.c,v 1.2 2002/02/21 07:38:19 itojun Exp $       */
2 
3 /*-
4  * Copyright (c) 2001 The NetBSD Foundation, Inc.
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  * 3. All advertising materials mentioning features or use of this software
16  *    must display the following acknowledgement:
17  *	This product includes software developed by the NetBSD
18  *	Foundation, Inc. and its contributors.
19  * 4. Neither the name of The NetBSD Foundation nor the names of its
20  *    contributors may be used to endorse or promote products derived
21  *    from this software without specific prior written permission.
22  *
23  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
24  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
25  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
26  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
27  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
28  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
29  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
30  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
31  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
32  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
33  * POSSIBILITY OF SUCH DAMAGE.
34  */
35 
36 #include <sys/types.h>
37 
38 __RCSID("$NetBSD: sigstackalign.c,v 1.2 2002/02/21 07:38:19 itojun Exp $");
39 
40 #include <signal.h>
41 #include <stdio.h>
42 #include <stdlib.h>
43 
44 #define RANGE 16
45 #define STACKALIGN 8
46 #define BLOCKSIZE (MINSIGSTKSZ + RANGE)
47 
48 extern void getstackptr(int);
49 
50 void *stackptr;
51 
52 int
53 main(int argc, char **argv)
54 {
55 	char *stackblock;
56 	int i, ret;
57 	struct sigaction sa;
58 	stack_t ss;
59 
60 	ret = 0;
61 
62 	sa.sa_handler = getstackptr;
63 	sigemptyset(&sa.sa_mask);
64 	sa.sa_flags = SA_ONSTACK;
65 	if (sigaction(SIGUSR1, &sa, NULL) != 0)
66 		err(1, "sigaction");
67 
68 	stackblock = malloc(BLOCKSIZE);
69 	for (i = 0; i < RANGE; i++) {
70 		ss.ss_sp = stackblock;
71 		ss.ss_size = MINSIGSTKSZ + i;
72 		ss.ss_flags = 0;
73 		if (sigaltstack(&ss, NULL) != 0)
74 			err(1, "sigaltstack");
75 		kill(getpid(), SIGUSR1);
76 		if ((u_int)stackptr % STACKALIGN != 0) {
77 			fprintf(stderr, "Bad stack pointer %p\n", stackptr);
78 			ret = 1;
79 		}
80 #if 0
81 		printf("i = %d, stackptr = %p\n", i, stackptr);
82 #endif
83 	}
84 
85 	return ret;
86 }
87 
88