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, Version 1.0 only
6 * (the "License"). You may not use this file except in compliance
7 * with the License.
8 *
9 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10 * or http://www.opensolaris.org/os/licensing.
11 * See the License for the specific language governing permissions
12 * and limitations under the License.
13 *
14 * When distributing Covered Code, include this CDDL HEADER in each
15 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16 * If applicable, add the following below this CDDL HEADER, with the
17 * fields enclosed by brackets "[]" replaced with your own identifying
18 * information: Portions Copyright [yyyy] [name of copyright owner]
19 *
20 * CDDL HEADER END
21 */
22 /* Copyright (c) 1988 AT&T */
23 /* All Rights Reserved */
24
25
26 /*
27 * Copyright (c) 1998 by Sun Microsystems, Inc.
28 * All rights reserved.
29 */
30
31 #include "libelf.h"
32 #include <unistd.h>
33 #include <fcntl.h>
34 #include <string.h>
35 #include <nlist.h>
36 #include "syms.h"
37 #include "gelf.h"
38
39 #undef n_name /* This undef is to handle a #define in syms.h */
40 /* which conflicts with the member nlist->n_name */
41 /* as defined in nlist.h */
42
43
44 #define SPACE 100 /* number of symbols read at a time */
45 #define ISELF (strncmp(magic_buf, ELFMAG, SELFMAG) == 0)
46
47
48 int
end_elf_job(int fd,Elf * elfdes)49 end_elf_job(int fd, Elf * elfdes)
50 {
51 (void) elf_end(elfdes);
52 (void) close(fd);
53 return (-1);
54 }
55
56
57 int
_elf_nlist(int fd,struct nlist * list)58 _elf_nlist(int fd, struct nlist * list)
59 {
60 Elf *elfdes; /* ELF descriptor */
61 GElf_Ehdr ehdr; /* ELF Ehdr */
62 GElf_Shdr s_buf; /* buffer storing section header */
63 Elf_Data *symdata; /* buffer points to symbol table */
64 Elf_Scn *secidx = 0; /* index of the section header table */
65 GElf_Sym sym; /* buffer storing one symbol information */
66 unsigned strtab; /* index of symbol name in string table */
67 long count; /* number of symbols */
68 long ii; /* loop control */
69
70 if (elf_version(EV_CURRENT) == EV_NONE) {
71 (void) close(fd);
72 return (-1);
73 }
74 elfdes = elf_begin(fd, ELF_C_READ, (Elf *)0);
75 if (gelf_getehdr(elfdes, &ehdr) == 0)
76 return (end_elf_job(fd, elfdes));
77
78 while ((secidx = elf_nextscn(elfdes, secidx)) != 0) {
79 if ((gelf_getshdr(secidx, &s_buf)) == 0)
80 return (end_elf_job(fd, elfdes));
81 if (s_buf.sh_type != SHT_SYMTAB) /* not symbol table */
82 continue;
83 symdata = elf_getdata(secidx, (Elf_Data *)0);
84 if (symdata == 0)
85 return (end_elf_job(fd, elfdes));
86 if (symdata->d_size == 0)
87 break;
88 strtab = s_buf.sh_link;
89 count = symdata->d_size / s_buf.sh_entsize;
90 for (ii = 1; ii < count; ++ii) {
91 struct nlist *p;
92 register char *name;
93 /* LINTED */
94 (void) gelf_getsym(symdata, (int)ii, &sym);
95 name = elf_strptr(elfdes, strtab, (size_t)sym.st_name);
96 if (name == 0)
97 continue;
98 for (p = list; p->n_name && p->n_name[0]; ++p) {
99 if (strcmp(p->n_name, name))
100 continue;
101 p->n_value = (long)sym.st_value;
102 p->n_type = GELF_ST_TYPE(sym.st_info);
103 p->n_scnum = sym.st_shndx;
104 break;
105 }
106 }
107 break;
108 /*
109 * Currently there is only one symbol table section
110 * in an object file, but this restriction may be
111 * relaxed in the future.
112 */
113 }
114 (void) elf_end(elfdes);
115 (void) close(fd);
116 return (0);
117 }
118
119 int
nlist(const char * name,struct nlist * list)120 nlist(const char * name, struct nlist * list)
121 {
122 register struct nlist *p;
123 char magic_buf[EI_NIDENT];
124 int fd;
125
126 for (p = list; p->n_name && p->n_name[0]; p++) { /* n_name can be ptr */
127 p->n_type = 0;
128 p->n_value = 0L;
129 p->n_scnum = 0;
130 p->n_sclass = 0;
131 p->n_numaux = 0;
132 }
133
134 if ((fd = open(name, 0)) < 0)
135 return (-1);
136 if (read(fd, magic_buf, EI_NIDENT) == -1) {
137 (void) close(fd);
138 return (-1);
139 }
140
141 if (lseek(fd, 0L, 0) == -1L) { /* rewind to beginning of object file */
142 (void) close(fd);
143 return (-1);
144 }
145
146 #ifndef _LP64
147 if (ISELF && (magic_buf[EI_CLASS] == ELFCLASS32))
148 #else
149 if (ISELF) /* 64-bit case handles both Elf32 and Elf64 */
150 #endif
151 return (_elf_nlist(fd, list));
152 else {
153 (void) close(fd);
154 return (-1);
155 }
156 }
157