1 /* Accumulation of various pieces of knowledge about ELF. 2 Copyright (C) 2000, 2001, 2002, 2003, 2005 Red Hat, Inc. 3 This file is part of Red Hat elfutils. 4 Written by Ulrich Drepper <drepper (at) redhat.com>, 2000. 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 #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 */ 128
