1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
|
/*-
* Copyright (c) 1983, 1993
* The Regents of the University of California. All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its contributors
* may be used to endorse or promote products derived from this software
* without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#include <sys/types.h>
#include <sys/mman.h>
#include <sys/stat.h>
#include <elf.h>
#include <err.h>
#include <fcntl.h>
#include <string.h>
#include <unistd.h>
#include "gprof.h"
static bool wantsym(const Elf_Sym *, const char *);
/* Things which get -E excluded by default. */
static char *excludes[] = { ".mcount", "_mcleanup", NULL };
int
getnfile(const char *filename, char ***defaultEs)
{
int fd;
Elf_Ehdr h;
struct stat s;
void *mapbase;
const char *base;
const Elf_Shdr *shdrs;
const Elf_Shdr *sh_symtab;
const Elf_Shdr *sh_strtab;
const char *strtab;
const Elf_Sym *symtab;
int symtabct;
int i;
if ((fd = open(filename, O_RDONLY)) == -1)
err(1, "%s", filename);
if (read(fd, &h, sizeof h) != sizeof h || !IS_ELF(h)) {
close(fd);
return -1;
}
if (fstat(fd, &s) == -1)
err(1, "Cannot fstat %s", filename);
if ((mapbase = mmap(0, s.st_size, PROT_READ, MAP_SHARED, fd, 0)) ==
MAP_FAILED)
err(1, "Cannot mmap %s", filename);
close(fd);
base = (const char *)mapbase;
shdrs = (const Elf_Shdr *)(base + h.e_shoff);
/* Find the symbol table and associated string table section. */
for (i = 1; i < h.e_shnum; i++)
if (shdrs[i].sh_type == SHT_SYMTAB)
break;
if (i == h.e_shnum)
errx(1, "%s has no symbol table", filename);
sh_symtab = &shdrs[i];
sh_strtab = &shdrs[sh_symtab->sh_link];
symtab = (const Elf_Sym *)(base + sh_symtab->sh_offset);
symtabct = sh_symtab->sh_size / sh_symtab->sh_entsize;
strtab = (const char *)(base + sh_strtab->sh_offset);
/* Count the symbols that we're interested in. */
nname = 0;
for (i = 1; i < symtabct; i++)
if (wantsym(&symtab[i], strtab))
nname++;
#ifdef DEBUG
if (debug & ELFDEBUG) {
printf("[getnfile] symtab at %p, strtab at %p\n", symtab, strtab);
printf("[getnfile] %d of %d symbols wanted\n", nname, symtabct);
}
#endif
/* Allocate memory for them, plus a terminating entry. */
if ((nl = calloc(nname + 1, sizeof(nltype))) == NULL)
errx(1, "Insufficient memory for symbol table");
/* Read them in. */
npe = nl;
for (i = 1; i < symtabct; i++) {
const Elf_Sym *sym = &symtab[i];
if (wantsym(sym, strtab)) {
npe->value = sym->st_value;
npe->name = strtab + sym->st_name;
#ifdef DEBUG
if (debug & ELFDEBUG)
printf("[getnfile] symbol %d: %s -> %lx\n", i,
npe->name ? npe->name : "(none)", npe->value);
#endif
npe++;
}
}
npe->value = -1;
*defaultEs = excludes;
return 0;
}
static bool
wantsym(const Elf_Sym *sym, const char *strtab)
{
int type;
int bind;
type = ELF_ST_TYPE(sym->st_info);
bind = ELF_ST_BIND(sym->st_info);
if (type != STT_FUNC || (aflag && bind == STB_LOCAL))
#if 0
||
(uflag && strchr(strtab + sym->st_name, '.') != NULL))
#endif
return 0;
#ifdef __arm__
/* ignore what gas calls "mapping symbols" */
{
const char *c = strtab + sym->st_name;
if (c[0] == '$')
return 0;
}
#endif
return 1;
}
|
