Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 1 | /* Accumulation of various pieces of knowledge about ELF. |
| 2 | Copyright (C) 2000, 2001, 2002, 2003, 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>, 2000. |
| 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. |
Ulrich Drepper | b08d5a8 | 2005-07-26 05:00:05 +0000 | [diff] [blame] | 14 | |
Ulrich Drepper | 361df7d | 2006-04-04 21:38:57 +0000 | [diff] [blame] | 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 | #ifndef _ELF_KNOWLEDGE_H |
| 52 | #define _ELF_KNOWLEDGE_H 1 |
| 53 | |
| 54 | #include <stdbool.h> |
| 55 | |
| 56 | |
| 57 | /* Test whether a section can be stripped or not. */ |
| 58 | #define SECTION_STRIP_P(shdr, name, remove_comment) \ |
| 59 | /* Sections which are allocated are not removed. */ \ |
| 60 | (((shdr)->sh_flags & SHF_ALLOC) == 0 \ |
| 61 | /* We never remove .note sections. */ \ |
| 62 | && (shdr)->sh_type != SHT_NOTE \ |
| 63 | && (((shdr)->sh_type) != SHT_PROGBITS \ |
| 64 | /* Never remove .gnu.warning.* sections. */ \ |
| 65 | || (strncmp (name, ".gnu.warning.", sizeof ".gnu.warning." - 1) != 0 \ |
| 66 | /* We remove .comment sections only if explicitly told to do so. */\ |
| 67 | && (remove_comment \ |
| 68 | || strcmp (name, ".comment") != 0))) \ |
| 69 | /* So far we do not remove any of the non-standard sections. \ |
| 70 | XXX Maybe in future. */ \ |
| 71 | && (shdr)->sh_type < SHT_NUM) |
| 72 | |
| 73 | |
| 74 | /* Test whether `sh_info' field in section header contains a section |
| 75 | index. There are two kinds of sections doing this: |
| 76 | |
| 77 | - the sections containing relocation information reference in this |
| 78 | field the section to which the relocations apply; |
| 79 | |
| 80 | - section with the SHF_INFO_LINK flag set to signal that `sh_info' |
| 81 | references a section. This allows correct handling of unknown |
| 82 | sections. */ |
| 83 | #define SH_INFO_LINK_P(Shdr) \ |
| 84 | ((Shdr)->sh_type == SHT_REL || (Shdr)->sh_type == SHT_RELA \ |
| 85 | || ((Shdr)->sh_flags & SHF_INFO_LINK) != 0) |
| 86 | |
| 87 | |
| 88 | /* When combining ELF section flags we must distinguish two kinds: |
| 89 | |
| 90 | - flags which cause problem if not added to the result even if not |
| 91 | present in all input sections |
| 92 | |
| 93 | - flags which cause problem if added to the result if not present |
| 94 | in all input sections |
| 95 | |
| 96 | The following definition is for the general case. There might be |
| 97 | machine specific extensions. */ |
| 98 | #define SH_FLAGS_COMBINE(Flags1, Flags2) \ |
| 99 | (((Flags1 | Flags2) \ |
| 100 | & (SHF_WRITE | SHF_ALLOC | SHF_EXECINSTR | SHF_LINK_ORDER \ |
| 101 | | SHF_OS_NONCONFORMING | SHF_GROUP)) \ |
| 102 | | (Flags1 & Flags2 & (SHF_MERGE | SHF_STRINGS | SHF_INFO_LINK))) |
| 103 | |
| 104 | /* Similar macro: return the bits of the flags which necessarily must |
| 105 | match if two sections are automatically combined. Sections still |
| 106 | can be forcefully combined in which case SH_FLAGS_COMBINE can be |
| 107 | used to determine the combined flags. */ |
| 108 | #define SH_FLAGS_IMPORTANT(Flags) \ |
| 109 | ((Flags) & ~((GElf_Xword) 0 | SHF_LINK_ORDER | SHF_OS_NONCONFORMING)) |
| 110 | |
| 111 | |
| 112 | /* Size of an entry in the hash table. The ELF specification says all |
| 113 | entries are regardless of platform 32-bits in size. Early 64-bit |
| 114 | ports (namely Alpha for Linux) got this wrong. The wording was not |
| 115 | clear. |
| 116 | |
| 117 | Several years later the ABI for the 64-bit S390s was developed. |
| 118 | Many things were copied from the IA-64 ABI (which uses the correct |
| 119 | 32-bit entry size) but what do these people do? They use 64-bit |
| 120 | entries. It is really shocking to see what kind of morons are out |
| 121 | there. And even worse: they are allowed to design ABIs. */ |
| 122 | #define SH_ENTSIZE_HASH(Ehdr) \ |
| 123 | ((Ehdr)->e_machine == EM_ALPHA \ |
| 124 | || ((Ehdr)->e_machine == EM_S390 \ |
| 125 | && (Ehdr)->e_ident[EI_CLASS] == ELFCLASS64) ? 8 : 4) |
| 126 | |
| 127 | #endif /* elf-knowledge.h */ |