1 /* $NetBSD: symtab.c,v 1.3 2013/09/03 08:44:45 christos Exp $ */
4 * Copyright (c) 2012 The NetBSD Foundation, Inc.
7 * This code is derived from software contributed to The NetBSD Foundation
10 * Redistribution and use in source and binary forms, with or without
11 * modification, are permitted provided that the following conditions
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.
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.
31 #include <sys/cdefs.h>
32 __RCSID("$NetBSD: symtab.c,v 1.3 2013/09/03 08:44:45 christos Exp $");
44 #define ELF_ST_BIND(x) ((x) >> 4)
47 #define ELF_ST_TYPE(x) (((unsigned int)x) & 0xf)
61 struct symbol
*symbols
;
65 address_compare(const void *a
, const void *b
)
67 const struct symbol
*sa
= a
;
68 const struct symbol
*sb
= b
;
69 return (int)(intmax_t)(sa
->st_value
- sb
->st_value
);
73 symtab_destroy(symtab_t
*s
)
77 for (size_t i
= 0; i
< s
->nsymbols
; i
++)
78 free(s
->symbols
[i
].st_name
);
84 symtab_create(int fd
, int bind
, int type
)
90 if (elf_version(EV_CURRENT
) == EV_NONE
) {
91 warnx("Elf Library is out of date.");
95 elf
= elf_begin(fd
, ELF_C_READ
, NULL
);
97 warnx("Error opening elf file: %s", elf_errmsg(elf_errno()));
100 st
= calloc(1, sizeof(*st
));
102 warnx("Error allocating symbol table");
107 while ((scn
= elf_nextscn(elf
, scn
)) != NULL
) {
113 gelf_getshdr(scn
, &shdr
);
114 if(shdr
.sh_type
!= SHT_SYMTAB
)
117 edata
= elf_getdata(scn
, NULL
);
118 ns
= shdr
.sh_size
/ shdr
.sh_entsize
;
119 s
= calloc(ns
, sizeof(*s
));
121 warn("Cannot allocate %zu symbols", ns
);
126 for (size_t i
= 0; i
< ns
; i
++) {
128 gelf_getsym(edata
, (int)i
, &sym
);
131 (unsigned)bind
!= ELF_ST_BIND(sym
.st_info
))
135 (unsigned)type
!= ELF_ST_TYPE(sym
.st_info
))
138 s
->st_value
= sym
.st_value
;
139 s
->st_info
= sym
.st_info
;
141 elf_strptr(elf
, shdr
.sh_link
, sym
.st_name
));
142 if (s
->st_name
== NULL
) {
143 warn("Cannot allocate symbol");
148 st
->nsymbols
= s
- st
->symbols
;
149 if (st
->nsymbols
== 0) {
150 warnx("No symbols found");
153 qsort(st
->symbols
, st
->nsymbols
, sizeof(*st
->symbols
),
166 symtab_find(const symtab_t
*st
, const void *p
, Dl_info
*dli
)
168 struct symbol
*s
= st
->symbols
;
169 size_t ns
= st
->nsymbols
;
173 uintptr_t dd
, sd
, me
= (uintptr_t)p
;
176 if (s
[mid
].st_value
< me
)
178 else if (s
[mid
].st_value
> me
)
188 dd
= me
- (uintptr_t)dli
->dli_saddr
;
189 sd
= me
- s
[mid
].st_value
;
191 dli
->dli_saddr
= (void *)s
[mid
].st_value
;
192 dli
->dli_sname
= s
[mid
].st_name
;