1/*-
2 * Copyright (c) 2006 Joseph Koshy
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27
28#include <sys/param.h>
| 1/*-
2 * Copyright (c) 2006 Joseph Koshy
3 * All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 * notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 * notice, this list of conditions and the following disclaimer in the
12 * documentation and/or other materials provided with the distribution.
13 *
14 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24 * SUCH DAMAGE.
25 */
26
27
28#include <sys/param.h>
|
| 29#ifdef __sun
30#include <sys/sysmacros.h>
31#endif
|
29
30#include <assert.h>
31#include "gelf.h"
32
33#include "_libelf.h"
34
35/*
36 * Convert an ELF section#,offset pair to a string pointer.
37 */
38
39char *
40elf_strptr(Elf *e, size_t scndx, size_t offset)
41{
42 Elf_Scn *s;
43 Elf_Data *d;
44 size_t alignment, count;
45 GElf_Shdr shdr;
46
47 if (e == NULL || e->e_kind != ELF_K_ELF) {
48 LIBELF_SET_ERROR(ARGUMENT, 0);
49 return (NULL);
50 }
51
52 if ((s = elf_getscn(e, scndx)) == NULL ||
53 gelf_getshdr(s, &shdr) == NULL)
54 return (NULL);
55
56 if (shdr.sh_type != SHT_STRTAB ||
57 offset >= shdr.sh_size) {
58 LIBELF_SET_ERROR(ARGUMENT, 0);
59 return (NULL);
60 }
61
62 d = NULL;
63 if (e->e_flags & ELF_F_LAYOUT) {
64
65 /*
66 * The application is taking responsibility for the
67 * ELF object's layout, so we can directly translate
68 * an offset to a `char *' address using the `d_off'
69 * members of Elf_Data descriptors.
70 */
71 while ((d = elf_getdata(s, d)) != NULL) {
72
73 if (d->d_buf == 0 || d->d_size == 0)
74 continue;
75
76 if (d->d_type != ELF_T_BYTE) {
77 LIBELF_SET_ERROR(DATA, 0);
78 return (NULL);
79 }
80
81 if (offset >= d->d_off &&
82 offset < d->d_off + d->d_size)
83 return ((char *) d->d_buf + offset - d->d_off);
84 }
85 } else {
86 /*
87 * Otherwise, the `d_off' members are not useable and
88 * we need to compute offsets ourselves, taking into
89 * account 'holes' in coverage of the section introduced
90 * by alignment requirements.
91 */
92 count = (size_t) 0; /* cumulative count of bytes seen */
93 while ((d = elf_getdata(s, d)) != NULL && count <= offset) {
94
95 if (d->d_buf == NULL || d->d_size == 0)
96 continue;
97
98 if (d->d_type != ELF_T_BYTE) {
99 LIBELF_SET_ERROR(DATA, 0);
100 return (NULL);
101 }
102
103 if ((alignment = d->d_align) > 1) {
104 if ((alignment & (alignment - 1)) != 0) {
105 LIBELF_SET_ERROR(DATA, 0);
106 return (NULL);
107 }
108 count = roundup(count, alignment);
109 }
110
111 if (offset < count) {
112 /* offset starts in the 'hole' */
113 LIBELF_SET_ERROR(ARGUMENT, 0);
114 return (NULL);
115 }
116
117 if (offset < count + d->d_size) {
118 if (d->d_buf != NULL)
119 return ((char *) d->d_buf +
120 offset - count);
121 LIBELF_SET_ERROR(DATA, 0);
122 return (NULL);
123 }
124
125 count += d->d_size;
126 }
127 }
128
129 LIBELF_SET_ERROR(ARGUMENT, 0);
130 return (NULL);
131}
| 32
33#include <assert.h>
34#include "gelf.h"
35
36#include "_libelf.h"
37
38/*
39 * Convert an ELF section#,offset pair to a string pointer.
40 */
41
42char *
43elf_strptr(Elf *e, size_t scndx, size_t offset)
44{
45 Elf_Scn *s;
46 Elf_Data *d;
47 size_t alignment, count;
48 GElf_Shdr shdr;
49
50 if (e == NULL || e->e_kind != ELF_K_ELF) {
51 LIBELF_SET_ERROR(ARGUMENT, 0);
52 return (NULL);
53 }
54
55 if ((s = elf_getscn(e, scndx)) == NULL ||
56 gelf_getshdr(s, &shdr) == NULL)
57 return (NULL);
58
59 if (shdr.sh_type != SHT_STRTAB ||
60 offset >= shdr.sh_size) {
61 LIBELF_SET_ERROR(ARGUMENT, 0);
62 return (NULL);
63 }
64
65 d = NULL;
66 if (e->e_flags & ELF_F_LAYOUT) {
67
68 /*
69 * The application is taking responsibility for the
70 * ELF object's layout, so we can directly translate
71 * an offset to a `char *' address using the `d_off'
72 * members of Elf_Data descriptors.
73 */
74 while ((d = elf_getdata(s, d)) != NULL) {
75
76 if (d->d_buf == 0 || d->d_size == 0)
77 continue;
78
79 if (d->d_type != ELF_T_BYTE) {
80 LIBELF_SET_ERROR(DATA, 0);
81 return (NULL);
82 }
83
84 if (offset >= d->d_off &&
85 offset < d->d_off + d->d_size)
86 return ((char *) d->d_buf + offset - d->d_off);
87 }
88 } else {
89 /*
90 * Otherwise, the `d_off' members are not useable and
91 * we need to compute offsets ourselves, taking into
92 * account 'holes' in coverage of the section introduced
93 * by alignment requirements.
94 */
95 count = (size_t) 0; /* cumulative count of bytes seen */
96 while ((d = elf_getdata(s, d)) != NULL && count <= offset) {
97
98 if (d->d_buf == NULL || d->d_size == 0)
99 continue;
100
101 if (d->d_type != ELF_T_BYTE) {
102 LIBELF_SET_ERROR(DATA, 0);
103 return (NULL);
104 }
105
106 if ((alignment = d->d_align) > 1) {
107 if ((alignment & (alignment - 1)) != 0) {
108 LIBELF_SET_ERROR(DATA, 0);
109 return (NULL);
110 }
111 count = roundup(count, alignment);
112 }
113
114 if (offset < count) {
115 /* offset starts in the 'hole' */
116 LIBELF_SET_ERROR(ARGUMENT, 0);
117 return (NULL);
118 }
119
120 if (offset < count + d->d_size) {
121 if (d->d_buf != NULL)
122 return ((char *) d->d_buf +
123 offset - count);
124 LIBELF_SET_ERROR(DATA, 0);
125 return (NULL);
126 }
127
128 count += d->d_size;
129 }
130 }
131
132 LIBELF_SET_ERROR(ARGUMENT, 0);
133 return (NULL);
134}
|