1/* Copyright (C) 2015 Red Hat, Inc.
2   This file is part of elfutils.
3
4   This file is free software; you can redistribute it and/or modify
5   it under the terms of the GNU General Public License as published by
6   the Free Software Foundation; either version 3 of the License, or
7   (at your option) any later version.
8
9   elfutils is distributed in the hope that it will be useful, but
10   WITHOUT ANY WARRANTY; without even the implied warranty of
11   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
12   GNU General Public License for more details.
13
14   You should have received a copy of the GNU General Public License
15   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
16
17#ifdef HAVE_CONFIG_H
18# include <config.h>
19#endif
20
21#include <sys/types.h>
22#include <sys/stat.h>
23#include <fcntl.h>
24#include <inttypes.h>
25#include <libelf.h>
26#include <gelf.h>
27#include <stdbool.h>
28#include <stdio.h>
29#include <string.h>
30#include <unistd.h>
31
32
33int
34main (int argc, char *argv[])
35{
36  int result = 0;
37  int cnt;
38
39  if (argc < 3
40      || (strcmp (argv[1], "read") != 0
41          && strcmp (argv[1], "mmap") != 0))
42    {
43      printf ("Usage: (read|mmap) files...\n");
44      return -1;
45    }
46
47  bool mmap = strcmp (argv[1], "mmap") == 0;
48
49  elf_version (EV_CURRENT);
50
51  for (cnt = 2; cnt < argc; ++cnt)
52    {
53      int fd = open (argv[cnt], O_RDONLY);
54
55      Elf *elf = elf_begin (fd, mmap ? ELF_C_READ_MMAP : ELF_C_READ, NULL);
56      if (elf == NULL)
57	{
58	  printf ("%s not usable %s\n", argv[cnt], elf_errmsg (-1));
59	  result = 1;
60	  close (fd);
61	  continue;
62	}
63
64      /* To get the section names.  */
65      size_t strndx;
66      elf_getshdrstrndx (elf, &strndx);
67
68      Elf_Scn *scn = NULL;
69      while ((scn = elf_nextscn (elf, scn)) != NULL)
70	{
71	  size_t idx = elf_ndxscn (scn);
72	  GElf_Shdr mem;
73	  GElf_Shdr *shdr = gelf_getshdr (scn, &mem);
74	  const char *name = elf_strptr (elf, strndx, shdr->sh_name);
75	  if ((shdr->sh_flags & SHF_COMPRESSED) != 0)
76	    {
77	      /* Real compressed section.  */
78	      if (elf_compress (scn, 0, 0) < 0)
79		{
80		  printf ("elf_compress failed for section %zd: %s\n",
81			  idx, elf_errmsg (-1));
82		  return -1;
83		}
84	      Elf_Data *d = elf_getdata (scn, NULL);
85	      printf ("%zd: %s, ELF compressed, size: %zx\n",
86		      idx, name, d->d_size);
87	    }
88	  else
89	    {
90	      /* Maybe an old GNU compressed .z section?  */
91	      if (name[0] == '.' && name[1] == 'z')
92		{
93		  if (elf_compress_gnu (scn, 0, 0) < 0)
94		    {
95		      printf ("elf_compress_gnu failed for section %zd: %s\n",
96			      idx, elf_errmsg (-1));
97		      return -1;
98		    }
99		  Elf_Data *d = elf_getdata (scn, NULL);
100		  printf ("%zd: %s, GNU compressed, size: %zx\n",
101			  idx, name, d->d_size);
102		}
103	      else
104		printf ("%zd: %s, NOT compressed\n", idx, name);
105	    }
106	}
107
108      elf_end (elf);
109      close (fd);
110    }
111
112  return result;
113}
114