xref: /dragonfly/lib/libexecinfo/builtin.c (revision 0ca59c34)
1 /*	$NetBSD: builtin.c,v 1.1 2012/05/26 22:02:29 christos Exp $	*/
2 
3 /*-
4  * Copyright (c) 2012 The NetBSD Foundation, Inc.
5  * All rights reserved.
6  *
7  * This code is derived from software contributed to The NetBSD Foundation
8  * by Christos Zoulas.
9  *
10  * Redistribution and use in source and binary forms, with or without
11  * modification, are permitted provided that the following conditions
12  * are met:
13  * 1. Redistributions of source code must retain the above copyright
14  *    notice, this list of conditions and the following disclaimer.
15  * 2. Redistributions in binary form must reproduce the above copyright
16  *    notice, this list of conditions and the following disclaimer in the
17  *    documentation and/or other materials provided with the distribution.
18  *
19  * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
20  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
21  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22  * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
23  * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
24  * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
25  * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
26  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
27  * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
28  * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
29  * POSSIBILITY OF SUCH DAMAGE.
30  */
31 #include <sys/cdefs.h>
32 #include <sys/param.h>
33 #include <sys/types.h>
34 
35 #include "execinfo.h"
36 
37 #ifdef __MACHINE_STACK_GROWS_UP
38 #define BELOW >
39 #else
40 #define BELOW <
41 #endif
42 
43 #ifdef __lint__
44 #define __builtin_frame_address(a)	((void *)a)
45 #endif
46 
47 struct frameinfo {
48 	struct frameinfo *next;
49 	void *return_address;
50 };
51 
52 size_t
53 backtrace(void **trace, size_t len)
54 {
55 	const struct frameinfo *frame = __builtin_frame_address(0);
56 	void *stack = &stack;
57 
58 	for (size_t i = 0; i < len; i++) {
59 		if ((const void *)frame BELOW stack)
60 			return i;
61 		trace[i] = frame->return_address;
62 		frame = frame->next;
63 	}
64 
65 	return len;
66 }
67