1/* Get macro information.
2   Copyright (C) 2002-2009 Red Hat, Inc.
3   This file is part of Red Hat elfutils.
4   Written by Ulrich Drepper <drepper@redhat.com>, 2002.
5
6   Red Hat elfutils is free software; you can redistribute it and/or modify
7   it under the terms of the GNU General Public License as published by the
8   Free Software Foundation; version 2 of the License.
9
10   Red Hat elfutils is distributed in the hope that it will be useful, but
11   WITHOUT ANY WARRANTY; without even the implied warranty of
12   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
13   General Public License for more details.
14
15   You should have received a copy of the GNU General Public License along
16   with Red Hat elfutils; if not, write to the Free Software Foundation,
17   Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA.
18
19   In addition, as a special exception, Red Hat, Inc. gives You the
20   additional right to link the code of Red Hat elfutils with code licensed
21   under any Open Source Initiative certified open source license
22   (http://www.opensource.org/licenses/index.php) which requires the
23   distribution of source code with any binary distribution and to
24   distribute linked combinations of the two.  Non-GPL Code permitted under
25   this exception must only link to the code of Red Hat elfutils through
26   those well defined interfaces identified in the file named EXCEPTION
27   found in the source code files (the "Approved Interfaces").  The files
28   of Non-GPL Code may instantiate templates or use macros or inline
29   functions from the Approved Interfaces without causing the resulting
30   work to be covered by the GNU General Public License.  Only Red Hat,
31   Inc. may make changes or additions to the list of Approved Interfaces.
32   Red Hat's grant of this exception is conditioned upon your not adding
33   any new exceptions.  If you wish to add a new Approved Interface or
34   exception, please contact Red Hat.  You must obey the GNU General Public
35   License in all respects for all of the Red Hat elfutils code and other
36   code used in conjunction with Red Hat elfutils except the Non-GPL Code
37   covered by this exception.  If you modify this file, you may extend this
38   exception to your version of the file, but you are not obligated to do
39   so.  If you do not wish to provide this exception without modification,
40   you must delete this exception statement from your version and license
41   this file solely under the GPL without exception.
42
43   Red Hat elfutils is an included package of the Open Invention Network.
44   An included package of the Open Invention Network is a package for which
45   Open Invention Network licensees cross-license their patents.  No patent
46   license is granted, either expressly or impliedly, by designation as an
47   included package.  Should you wish to participate in the Open Invention
48   Network licensing program, please visit www.openinventionnetwork.com
49   <http://www.openinventionnetwork.com>.  */
50
51#ifdef HAVE_CONFIG_H
52# include <config.h>
53#endif
54
55#include <dwarf.h>
56#include <string.h>
57
58#include <libdwP.h>
59
60
61ptrdiff_t
62dwarf_getmacros (die, callback, arg, offset)
63     Dwarf_Die *die;
64     int (*callback) (Dwarf_Macro *, void *);
65     void *arg;
66     ptrdiff_t offset;
67{
68  if (die == NULL)
69    return -1;
70
71  Elf_Data *d = die->cu->dbg->sectiondata[IDX_debug_macinfo];
72  if (unlikely (d == NULL) || unlikely (d->d_buf == NULL))
73    {
74      __libdw_seterrno (DWARF_E_NO_ENTRY);
75      return -1;
76    }
77
78  if (offset == 0)
79    {
80      /* Get the appropriate attribute.  */
81      Dwarf_Attribute attr;
82      if (INTUSE(dwarf_attr) (die, DW_AT_macro_info, &attr) == NULL)
83	return -1;
84
85      /* Offset into the .debug_macinfo section.  */
86      Dwarf_Word macoff;
87      if (INTUSE(dwarf_formudata) (&attr, &macoff) != 0)
88	return -1;
89
90      offset = macoff;
91    }
92  if (unlikely (offset > (ptrdiff_t) d->d_size))
93    goto invalid;
94
95  const unsigned char *readp = d->d_buf + offset;
96  const unsigned char *readendp = d->d_buf + d->d_size;
97
98  if (readp == readendp)
99    return 0;
100
101  while (readp < readendp)
102    {
103      unsigned int opcode = *readp++;
104      unsigned int u128;
105      unsigned int u128_2 = 0;
106      const char *str = NULL;
107      const unsigned char *endp;
108
109      switch (opcode)
110	{
111	case DW_MACINFO_define:
112	case DW_MACINFO_undef:
113	case DW_MACINFO_vendor_ext:
114	  /*  For the first two opcodes the parameters are
115	        line, string
116	      For the latter
117	        number, string.
118	      We can treat these cases together.  */
119	  get_uleb128 (u128, readp);
120
121	  endp = memchr (readp, '\0', readendp - readp);
122	  if (endp == NULL)
123	    goto invalid;
124
125	  str = (char *) readp;
126	  readp = endp + 1;
127	  break;
128
129	case DW_MACINFO_start_file:
130	  /* The two parameters are line and file index.  */
131	  get_uleb128 (u128, readp);
132	  get_uleb128 (u128_2, readp);
133	  break;
134
135	case DW_MACINFO_end_file:
136	  /* No parameters for this one.  */
137	  u128 = 0;
138	  break;
139
140	case 0:
141	  /* Nothing more to do.  */
142	  return 0;
143
144	default:
145	  goto invalid;
146	}
147
148      Dwarf_Macro mac;
149      mac.opcode = opcode;
150      mac.param1 = u128;
151      if (str == NULL)
152	mac.param2.u = u128_2;
153      else
154	mac.param2.s = str;
155
156      if (callback (&mac, arg) != DWARF_CB_OK)
157	return readp - (const unsigned char *) d->d_buf;
158    }
159
160  /* If we come here the termination of the data for the CU is not
161     present.  */
162 invalid:
163  __libdw_seterrno (DWARF_E_INVALID_DWARF);
164  return -1;
165}
166