xref: /illumos-gate/usr/src/cmd/sgs/rtld/amd64/dlamd64getunwind.c (revision b1d7ec75953cd517f5b7c3d9cb427ff8ec5d7d07)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright (c) 2004, 2010, Oracle and/or its affiliates. All rights reserved.
24  */
25 
26 #include	<string.h>
27 #include	<dlfcn.h>
28 #include	<stdio.h>
29 #include	<debug.h>
30 #include	"_rtld.h"
31 #include	"_elf.h"
32 #include	"_inline_gen.h"
33 #include	"msg.h"
34 
35 
36 static Dl_amd64_unwindinfo *
37 getunwind_core(Lm_list *lml, void *pc, Dl_amd64_unwindinfo *unwindinfo)
38 {
39 	Rt_map	*lmp;
40 
41 	/*
42 	 * Validate the version information.
43 	 */
44 	if (unwindinfo == NULL) {
45 		eprintf(lml, ERR_FATAL, MSG_INTL(MSG_ARG_ILLVAL));
46 		return (0);
47 	}
48 	if ((unwindinfo->dlui_version < DLUI_VERS_1) ||
49 	    (unwindinfo->dlui_version > DLUI_VERS_CURRENT)) {
50 		eprintf(lml, ERR_FATAL, MSG_INTL(MSG_UNW_BADVERS),
51 		    unwindinfo->dlui_version, DLUI_VERS_CURRENT);
52 		return (0);
53 	}
54 
55 	/*
56 	 * Clean out the structure.
57 	 */
58 	unwindinfo->dlui_flags = 0;
59 	unwindinfo->dlui_objname = 0;
60 	unwindinfo->dlui_unwindstart = 0;
61 	unwindinfo->dlui_unwindend = 0;
62 	unwindinfo->dlui_segstart = 0;
63 	unwindinfo->dlui_segend = 0;
64 
65 	/*
66 	 * Identify the link-map associated with the exception "pc".  Note,
67 	 * the "pc" might not correspond to a link-map (as can happen with a
68 	 * "pc" fabricated by a debugger such as dbx).  In this case, the
69 	 * unwind data buffer will be filled with flags set to indicate an
70 	 * unknown caller.
71 	 */
72 	lmp = _caller(pc, CL_NONE);
73 
74 	if (lmp) {
75 		mmapobj_result_t	*mpp;
76 
77 		/*
78 		 * Determine the associated segment.
79 		 */
80 		if ((mpp = find_segment(pc, lmp)) == NULL)
81 			return (0);
82 
83 		unwindinfo->dlui_objname = (char *)PATHNAME(lmp);
84 		unwindinfo->dlui_segstart = mpp->mr_addr;
85 		unwindinfo->dlui_segend = mpp->mr_addr + mpp->mr_msize;
86 
87 		if (PTUNWIND(lmp) && (mpp->mr_addr)) {
88 			uintptr_t   base;
89 
90 			if (FLAGS(lmp) & FLG_RT_FIXED)
91 				base = 0;
92 			else
93 				base = ADDR(lmp);
94 
95 			unwindinfo->dlui_unwindstart =
96 			    (void *)(PTUNWIND(lmp)->p_vaddr + base);
97 			unwindinfo->dlui_unwindend =
98 			    (void *)(PTUNWIND(lmp)->p_vaddr +
99 			    PTUNWIND(lmp)->p_memsz + base);
100 
101 		} else if (mpp->mr_addr)
102 			unwindinfo->dlui_flags |= DLUI_FLG_NOUNWIND;
103 		else
104 			unwindinfo->dlui_flags |=
105 			    DLUI_FLG_NOUNWIND | DLUI_FLG_NOOBJ;
106 	} else {
107 		/*
108 		 * No object found.
109 		 */
110 		unwindinfo->dlui_flags = DLUI_FLG_NOOBJ | DLUI_FLG_NOUNWIND;
111 	}
112 	return (unwindinfo);
113 }
114 
115 #pragma weak _dlamd64getunwind = dlamd64getunwind
116 
117 Dl_amd64_unwindinfo *
118 dlamd64getunwind(void *pc, Dl_amd64_unwindinfo *unwindinfo)
119 {
120 	Rt_map	*lmp;
121 	Lm_list	*lml;
122 	int	entry = enter(0);
123 
124 	lmp = _caller(caller(), CL_EXECDEF);
125 	lml = LIST(lmp);
126 
127 	unwindinfo = getunwind_core(lml, pc, unwindinfo);
128 
129 	if (entry)
130 		leave(lml, 0);
131 	return (unwindinfo);
132 }
133