1/* Helper functions for form handling.
2   Copyright (C) 2003, 2004, 2006, 2007 Red Hat, Inc.
3   This file is part of Red Hat elfutils.
4   Written by Ulrich Drepper <drepper@redhat.com>, 2003.
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
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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
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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
61size_t
62internal_function
63__libdw_form_val_len (Dwarf *dbg, struct Dwarf_CU *cu, unsigned int form,
64		      const unsigned char *valp)
65{
66  const unsigned char *saved;
67  Dwarf_Word u128;
68  size_t result;
69
70  switch (form)
71    {
72    case DW_FORM_addr:
73      result = cu->address_size;
74      break;
75
76    case DW_FORM_ref_addr:
77      result = cu->version == 2 ? cu->address_size : cu->offset_size;
78      break;
79
80    case DW_FORM_strp:
81      result = cu->offset_size;
82      break;
83
84    case DW_FORM_block1:
85      result = *valp + 1;
86      break;
87
88    case DW_FORM_block2:
89      result = read_2ubyte_unaligned (dbg, valp) + 2;
90      break;
91
92    case DW_FORM_block4:
93      result = read_4ubyte_unaligned (dbg, valp) + 4;
94      break;
95
96    case DW_FORM_block:
97      saved = valp;
98      get_uleb128 (u128, valp);
99      result = u128 + (valp - saved);
100      break;
101
102    case DW_FORM_ref1:
103    case DW_FORM_data1:
104    case DW_FORM_flag:
105      result = 1;
106      break;
107
108    case DW_FORM_data2:
109    case DW_FORM_ref2:
110      result = 2;
111      break;
112
113    case DW_FORM_data4:
114    case DW_FORM_ref4:
115      result = 4;
116      break;
117
118    case DW_FORM_data8:
119    case DW_FORM_ref8:
120      result = 8;
121      break;
122
123    case DW_FORM_string:
124      result = strlen ((char *) valp) + 1;
125      break;
126
127    case DW_FORM_sdata:
128    case DW_FORM_udata:
129    case DW_FORM_ref_udata:
130      saved = valp;
131      get_uleb128 (u128, valp);
132      result = valp - saved;
133      break;
134
135    case DW_FORM_indirect:
136      saved = valp;
137      get_uleb128 (u128, valp);
138      // XXX Is this really correct?
139      result = __libdw_form_val_len (dbg, cu, u128, valp);
140      if (result != (size_t) -1)
141	result += valp - saved;
142      break;
143
144    default:
145      __libdw_seterrno (DWARF_E_INVALID_DWARF);
146      result = (size_t) -1l;
147      break;
148    }
149
150  return result;
151}
152