Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 1 | /* Advance to next CU header. |
| 2 | Copyright (C) 2002, 2003, 2004, 2005 Red Hat, Inc. |
Ulrich Drepper | 361df7d | 2006-04-04 21:38:57 +0000 | [diff] [blame] | 3 | This file is part of Red Hat elfutils. |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 4 | Written by Ulrich Drepper <drepper@redhat.com>, 2002. |
| 5 | |
Ulrich Drepper | 361df7d | 2006-04-04 21:38:57 +0000 | [diff] [blame] | 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. |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 9 | |
Ulrich Drepper | 361df7d | 2006-04-04 21:38:57 +0000 | [diff] [blame] | 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, |
Ulrich Drepper | 1e9ef50 | 2006-04-04 22:29:06 +0000 | [diff] [blame] | 17 | Inc., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301 USA. |
Ulrich Drepper | 361df7d | 2006-04-04 21:38:57 +0000 | [diff] [blame] | 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>. */ |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 50 | |
| 51 | #ifdef HAVE_CONFIG_H |
| 52 | # include <config.h> |
| 53 | #endif |
| 54 | |
| 55 | #include <libdwP.h> |
Ulrich Drepper | 35f08c4 | 2008-01-18 19:59:08 +0000 | [diff] [blame^] | 56 | #include <dwarf.h> |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 57 | |
| 58 | |
| 59 | int |
| 60 | dwarf_nextcu (dwarf, off, next_off, header_sizep, abbrev_offsetp, |
| 61 | address_sizep, offset_sizep) |
| 62 | Dwarf *dwarf; |
| 63 | Dwarf_Off off; |
| 64 | Dwarf_Off *next_off; |
| 65 | size_t *header_sizep; |
| 66 | Dwarf_Off *abbrev_offsetp; |
| 67 | uint8_t *address_sizep; |
| 68 | uint8_t *offset_sizep; |
| 69 | { |
| 70 | /* Maybe there has been an error before. */ |
| 71 | if (dwarf == NULL) |
| 72 | return -1; |
| 73 | |
| 74 | /* If we reached the end before don't do anything. */ |
| 75 | if (off == (Dwarf_Off) -1l |
| 76 | /* Make sure there is enough space in the .debug_info section |
| 77 | for at least the initial word. We cannot test the rest since |
| 78 | we don't know yet whether this is a 64-bit object or not. */ |
| 79 | || unlikely (off + 4 >= dwarf->sectiondata[IDX_debug_info]->d_size)) |
| 80 | { |
| 81 | *next_off = (Dwarf_Off) -1l; |
| 82 | return 1; |
| 83 | } |
| 84 | |
| 85 | /* This points into the .debug_info section to the beginning of the |
| 86 | CU entry. */ |
| 87 | char *bytes = (char *) dwarf->sectiondata[IDX_debug_info]->d_buf + off; |
| 88 | |
| 89 | /* The format of the CU header is described in dwarf2p1 7.5.1: |
| 90 | |
| 91 | 1. A 4-byte or 12-byte unsigned integer representing the length |
| 92 | of the .debug_info contribution for that compilation unit, not |
| 93 | including the length field itself. In the 32-bit DWARF format, |
| 94 | this is a 4-byte unsigned integer (which must be less than |
Ulrich Drepper | 35f08c4 | 2008-01-18 19:59:08 +0000 | [diff] [blame^] | 95 | 0xfffffff0); in the 64-bit DWARF format, this consists of the |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 96 | 4-byte value 0xffffffff followed by an 8-byte unsigned integer |
Ulrich Drepper | 35f08c4 | 2008-01-18 19:59:08 +0000 | [diff] [blame^] | 97 | that gives the actual length (see Section 7.2.2). |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 98 | |
| 99 | 2. A 2-byte unsigned integer representing the version of the |
| 100 | DWARF information for that compilation unit. For DWARF Version |
| 101 | 2.1, the value in this field is 2. |
| 102 | |
| 103 | 3. A 4-byte or 8-byte unsigned offset into the .debug_abbrev |
| 104 | section. This offset associates the compilation unit with a |
| 105 | particular set of debugging information entry abbreviations. In |
| 106 | the 32-bit DWARF format, this is a 4-byte unsigned length; in |
| 107 | the 64-bit DWARF format, this is an 8-byte unsigned length (see |
| 108 | Section 7.4). |
| 109 | |
| 110 | 4. A 1-byte unsigned integer representing the size in bytes of |
| 111 | an address on the target architecture. If the system uses |
| 112 | segmented addressing, this value represents the size of the |
| 113 | offset portion of an address. */ |
| 114 | uint64_t length = read_4ubyte_unaligned_inc (dwarf, bytes); |
| 115 | size_t offset_size = 4; |
Ulrich Drepper | 35f08c4 | 2008-01-18 19:59:08 +0000 | [diff] [blame^] | 116 | /* Lengths of 0xfffffff0 - 0xffffffff are escape codes. Oxffffffff is |
| 117 | used to indicate that 64-bit dwarf information is being used, the |
| 118 | other values are currently reserved. */ |
| 119 | if (length == DWARF3_LENGTH_64_BIT) |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 120 | offset_size = 8; |
Ulrich Drepper | 35f08c4 | 2008-01-18 19:59:08 +0000 | [diff] [blame^] | 121 | else if (unlikely (length >= DWARF3_LENGTH_MIN_ESCAPE_CODE |
| 122 | && length <= DWARF3_LENGTH_MAX_ESCAPE_CODE)) |
| 123 | { |
| 124 | __libdw_seterrno (DWARF_E_INVALID_DWARF); |
| 125 | return -1; |
| 126 | } |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 127 | |
Ulrich Drepper | 35f08c4 | 2008-01-18 19:59:08 +0000 | [diff] [blame^] | 128 | /* Now we know how large the header is. */ |
| 129 | if (unlikely (DIE_OFFSET_FROM_CU_OFFSET (off, offset_size) |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 130 | >= dwarf->sectiondata[IDX_debug_info]->d_size)) |
| 131 | { |
| 132 | *next_off = -1; |
| 133 | return 1; |
| 134 | } |
| 135 | |
Ulrich Drepper | 35f08c4 | 2008-01-18 19:59:08 +0000 | [diff] [blame^] | 136 | if (length == DWARF3_LENGTH_64_BIT) |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 137 | /* This is a 64-bit DWARF format. */ |
| 138 | length = read_8ubyte_unaligned_inc (dwarf, bytes); |
| 139 | |
| 140 | /* Read the version stamp. Always a 16-bit value. |
| 141 | XXX Do we need the value? */ |
| 142 | read_2ubyte_unaligned_inc (dwarf, bytes); |
| 143 | |
| 144 | /* Get offset in .debug_abbrev. Note that the size of the entry |
| 145 | depends on whether this is a 32-bit or 64-bit DWARF definition. */ |
| 146 | uint64_t abbrev_offset; |
| 147 | if (offset_size == 4) |
| 148 | abbrev_offset = read_4ubyte_unaligned_inc (dwarf, bytes); |
| 149 | else |
| 150 | abbrev_offset = read_8ubyte_unaligned_inc (dwarf, bytes); |
| 151 | if (abbrev_offsetp != NULL) |
| 152 | *abbrev_offsetp = abbrev_offset; |
| 153 | |
| 154 | /* The address size. Always an 8-bit value. */ |
| 155 | uint8_t address_size = *bytes++; |
| 156 | if (address_sizep != NULL) |
| 157 | *address_sizep = address_size; |
| 158 | |
| 159 | /* Store the offset size. */ |
| 160 | if (offset_sizep != NULL) |
| 161 | *offset_sizep = offset_size; |
| 162 | |
| 163 | /* Store the header length. */ |
| 164 | if (header_sizep != NULL) |
| 165 | *header_sizep = (bytes |
| 166 | - ((char *) dwarf->sectiondata[IDX_debug_info]->d_buf |
| 167 | + off)); |
| 168 | |
Ulrich Drepper | 35f08c4 | 2008-01-18 19:59:08 +0000 | [diff] [blame^] | 169 | /* See definition of DIE_OFFSET_FROM_CU_OFFSET macro |
| 170 | for an explanation of the trick in this expression. */ |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 171 | *next_off = off + 2 * offset_size - 4 + length; |
| 172 | |
| 173 | return 0; |
| 174 | } |
| 175 | INTDEF(dwarf_nextcu) |