1 /* $NetBSD: libdwarf_loclist.c,v 1.5 2024/03/03 17:37:32 christos Exp $ */
2
3 /*-
4 * Copyright (c) 2009,2011 Kai Wang
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 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29 #include "_libdwarf.h"
30
31 __RCSID("$NetBSD: libdwarf_loclist.c,v 1.5 2024/03/03 17:37:32 christos Exp $");
32 ELFTC_VCSID("Id: libdwarf_loclist.c 3061 2014-06-02 00:42:41Z kaiwang27");
33
34 static int
_dwarf_loclist_add_locdesc(Dwarf_Debug dbg,Dwarf_CU cu,Dwarf_Section * ds,Dwarf_Unsigned * off,Dwarf_Locdesc ** ld,Dwarf_Signed * ldlen,Dwarf_Unsigned * total_len,Dwarf_Error * error)35 _dwarf_loclist_add_locdesc(Dwarf_Debug dbg, Dwarf_CU cu, Dwarf_Section *ds,
36 Dwarf_Unsigned *off, Dwarf_Locdesc **ld, Dwarf_Signed *ldlen,
37 Dwarf_Unsigned *total_len, Dwarf_Error *error)
38 {
39 uint64_t start, end;
40 int i, len, ret;
41
42 if (total_len != NULL)
43 *total_len = 0;
44
45 for (i = 0; *off < ds->ds_size; i++) {
46 start = dbg->read(ds->ds_data, off, cu->cu_pointer_size);
47 end = dbg->read(ds->ds_data, off, cu->cu_pointer_size);
48 if (ld != NULL) {
49 ld[i]->ld_lopc = start;
50 ld[i]->ld_hipc = end;
51 }
52
53 if (total_len != NULL)
54 *total_len += 2 * cu->cu_pointer_size;
55
56 /* Check if it is the end entry. */
57 if (start == 0 && end ==0) {
58 i++;
59 break;
60 }
61
62 /* Check if it is base-select entry. */
63 if ((cu->cu_pointer_size == 4 && start == ~0U) ||
64 (cu->cu_pointer_size == 8 && start == ~0ULL))
65 continue;
66
67 /* Otherwise it's normal entry. */
68 len = dbg->read(ds->ds_data, off, 2);
69 if (*off + len > ds->ds_size) {
70 DWARF_SET_ERROR(dbg, error,
71 DW_DLE_DEBUG_LOC_SECTION_SHORT);
72 return (DW_DLE_DEBUG_LOC_SECTION_SHORT);
73 }
74
75 if (total_len != NULL)
76 *total_len += len;
77
78 if (ld != NULL) {
79 ret = _dwarf_loc_fill_locdesc(dbg, ld[i],
80 ds->ds_data + *off, len, cu->cu_pointer_size,
81 cu->cu_length_size == 4 ? 4 : 8, cu->cu_version,
82 error);
83 if (ret != DW_DLE_NONE)
84 return (ret);
85 }
86
87 *off += len;
88 }
89
90 if (ldlen != NULL)
91 *ldlen = i;
92
93 return (DW_DLE_NONE);
94 }
95
96 int
_dwarf_loclist_find(Dwarf_Debug dbg,Dwarf_CU cu,uint64_t lloff,Dwarf_Locdesc *** ret_llbuf,Dwarf_Signed * listlen,Dwarf_Unsigned * entry_len,Dwarf_Error * error)97 _dwarf_loclist_find(Dwarf_Debug dbg, Dwarf_CU cu, uint64_t lloff,
98 Dwarf_Locdesc ***ret_llbuf, Dwarf_Signed *listlen,
99 Dwarf_Unsigned *entry_len, Dwarf_Error *error)
100 {
101 Dwarf_Locdesc **llbuf;
102 Dwarf_Section *ds;
103 Dwarf_Signed ldlen;
104 Dwarf_Unsigned off;
105 int i, ret;
106
107 if ((ds = _dwarf_find_section(dbg, ".debug_loc")) == NULL) {
108 DWARF_SET_ERROR(dbg, error, DW_DLE_NO_ENTRY);
109 return (DW_DLE_NO_ENTRY);
110 }
111
112 if (lloff >= ds->ds_size) {
113 DWARF_SET_ERROR(dbg, error, DW_DLE_NO_ENTRY);
114 return (DW_DLE_NO_ENTRY);
115 }
116
117 /* Get the number of locdesc the first round. */
118 off = lloff;
119 ret = _dwarf_loclist_add_locdesc(dbg, cu, ds, &off, NULL, &ldlen,
120 NULL, error);
121 if (ret != DW_DLE_NONE)
122 return (ret);
123
124 if (ldlen == 0)
125 return (DW_DLE_NO_ENTRY);
126
127 /*
128 * Dwarf_Locdesc list memory is allocated in this way (one more level
129 * of indirect) to make the loclist API be compatible with SGI libdwarf.
130 */
131 if ((llbuf = calloc(ldlen, sizeof(Dwarf_Locdesc *))) == NULL) {
132 DWARF_SET_ERROR(dbg, error, DW_DLE_MEMORY);
133 return (DW_DLE_MEMORY);
134 }
135 for (i = 0; i < ldlen; i++) {
136 if ((llbuf[i] = calloc(1, sizeof(Dwarf_Locdesc))) == NULL) {
137 DWARF_SET_ERROR(dbg, error, DW_DLE_MEMORY);
138 ret = DW_DLE_MEMORY;
139 goto fail_cleanup;
140 }
141 }
142
143 off = lloff;
144
145 /* Fill in locdesc. */
146 ret = _dwarf_loclist_add_locdesc(dbg, cu, ds, &off, llbuf, NULL,
147 entry_len, error);
148 if (ret != DW_DLE_NONE)
149 goto fail_cleanup;
150
151 *ret_llbuf = llbuf;
152 *listlen = ldlen;
153
154 return (DW_DLE_NONE);
155
156 fail_cleanup:
157
158 if (llbuf != NULL) {
159 for (i = 0; i < ldlen; i++) {
160 if (llbuf[i]->ld_s)
161 free(llbuf[i]->ld_s);
162 free(llbuf[i]);
163 }
164 free(llbuf);
165 }
166
167 return (ret);
168 }
169