summaryrefslogtreecommitdiffstats
path: root/tests/next_cfi.c
blob: 6a847b4dd668ca69b972628d13dbe9d0449730dd (plain)
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
/* Test program for dwarf_next_cfi
   Copyright (C) 2018 Red Hat, Inc.
   This file is part of elfutils.

   This file is free software; you can redistribute it and/or modify
   it under the terms of the GNU General Public License as published by
   the Free Software Foundation; either version 3 of the License, or
   (at your option) any later version.

   elfutils is distributed in the hope that it will be useful, but
   WITHOUT ANY WARRANTY; without even the implied warranty of
   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
   GNU General Public License for more details.

   You should have received a copy of the GNU General Public License
   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */

#include <config.h>
#include <assert.h>
#include <inttypes.h>
#include ELFUTILS_HEADER(dw)
#include <dwarf.h>
#include <argp.h>
#include <stdbool.h>
#include <stdio.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <locale.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include "system.h"

void
handle_section (char *name, const unsigned char e_ident[],
		Elf_Scn *scn, const bool is_eh)
{
  if (is_eh)
    printf (".eh_frame\n");
  else
    printf (".debug_frame\n");

  GElf_Shdr mem;
  GElf_Shdr *shdr = gelf_getshdr (scn, &mem);
  if (shdr == NULL)
    error (EXIT_FAILURE, 0, "Couldn't get section header: %s",
	   elf_errmsg (-1));
  if ((shdr->sh_flags & SHF_COMPRESSED) != 0)
    {
      if (elf_compress (scn, 0, 0) < 0)
	error (EXIT_FAILURE, 0, "Couldn't decompress section: %s",
	       elf_errmsg (-1));
    }
  else if (name[0] == '.' && name[1] == 'z')
    {
      if (elf_compress_gnu (scn, 0, 0) < 0)
	error (EXIT_FAILURE, 0, "Couldn't decompress section: %s",
	       elf_errmsg (-1));
    }

  Elf_Data *data = elf_getdata (scn, NULL);
  if (data == NULL || data->d_buf == NULL)
    error (EXIT_FAILURE, 0, "no section data");

  int res;
  Dwarf_Off off;
  Dwarf_Off next_off = 0;
  Dwarf_CFI_Entry entry;
  while ((res = dwarf_next_cfi (e_ident, data, is_eh, off = next_off,
				&next_off, &entry)) == 0)
    {
      printf ("[%" PRId64 "] ", off);
      if (dwarf_cfi_cie_p (&entry))
	printf ("CIE augmentation=\"%s\"\n", entry.cie.augmentation);
      else
	{
	  printf ("FDE cie=[%" PRId64 "]\n", entry.fde.CIE_pointer);

	  Dwarf_Off cie_off = entry.fde.CIE_pointer;
	  Dwarf_Off cie_off_next;
	  Dwarf_CFI_Entry cie_entry;
	  if (dwarf_next_cfi (e_ident, data, is_eh, cie_off, &cie_off_next,
			      &cie_entry) != 0
	      || !dwarf_cfi_cie_p (&cie_entry))
	    error (EXIT_FAILURE, 0, "FDE doesn't point to CIE");
	}
    }

  if (res < 0)
    error (EXIT_FAILURE, 0, "dwarf_next_cfi failed: %s\n",
	   dwarf_errmsg (-1));
}

int
main (int argc, char *argv[])
{
  if (argc != 2)
    error (EXIT_FAILURE, 0, "need file name argument");

  const char *file = argv[1];
  printf ("%s\n", file);

  int fd = open (file, O_RDONLY);
  if (fd == -1)
    error (EXIT_FAILURE, errno, "cannot open input file `%s'", file);

  elf_version (EV_CURRENT);

  Elf *elf = elf_begin (fd, ELF_C_READ, NULL);
  if (elf == NULL)
    error (EXIT_FAILURE, 0, "cannot create ELF descriptor: %s",
	   elf_errmsg (-1));

  size_t esize;
  const unsigned char *ident = (const unsigned char *) elf_getident (elf,
								     &esize);
  if (ident == NULL || esize < EI_NIDENT)
    error (EXIT_FAILURE, 0, "no, or too small, ELF ident");

  GElf_Ehdr ehdr;
  if (gelf_getehdr (elf, &ehdr) == NULL)
    error (EXIT_FAILURE, 0, "cannot get the ELF header: %s\n",
	   elf_errmsg (-1));

  size_t strndx = ehdr.e_shstrndx;

  Elf_Scn *scn = NULL;
  while ((scn = elf_nextscn (elf, scn)) != NULL)
    {
      GElf_Shdr shdr;
      if (gelf_getshdr (scn, &shdr) != NULL)
	{
	  char *name = elf_strptr (elf, strndx, (size_t) shdr.sh_name);
	  if (name != NULL && shdr.sh_type == SHT_PROGBITS)
	    {
	      if (strcmp (name, ".eh_frame") == 0)
		handle_section (name, ident, scn, true);
	      if (strcmp (name, ".debug_frame") == 0
		  || strcmp (name, ".zdebug_frame") == 0)
		handle_section (name, ident, scn, false);
	    }
	}
    }

  elf_end (elf);
  close (fd);

  return 0;
}