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+/* Accumulation of various pieces of knowledge about ELF.
+ Copyright (C) 2000, 2001, 2002, 2003, 2005 Red Hat, Inc.
+ Written by Ulrich Drepper <[email protected]>, 2000.
+
+ This program is free software; you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, version 2.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program; if not, write to the Free Software Foundation,
+ Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */
+
+#ifndef _ELF_KNOWLEDGE_H
+#define _ELF_KNOWLEDGE_H 1
+
+#include <stdbool.h>
+
+
+/* Test whether a section can be stripped or not. */
+#define SECTION_STRIP_P(shdr, name, remove_comment) \
+ /* Sections which are allocated are not removed. */ \
+ (((shdr)->sh_flags & SHF_ALLOC) == 0 \
+ /* We never remove .note sections. */ \
+ && (shdr)->sh_type != SHT_NOTE \
+ && (((shdr)->sh_type) != SHT_PROGBITS \
+ /* Never remove .gnu.warning.* sections. */ \
+ || (strncmp (name, ".gnu.warning.", sizeof ".gnu.warning." - 1) != 0 \
+ /* We remove .comment sections only if explicitly told to do so. */\
+ && (remove_comment \
+ || strcmp (name, ".comment") != 0))) \
+ /* So far we do not remove any of the non-standard sections. \
+ XXX Maybe in future. */ \
+ && (shdr)->sh_type < SHT_NUM)
+
+
+/* Test whether `sh_info' field in section header contains a section
+ index. There are two kinds of sections doing this:
+
+ - the sections containing relocation information reference in this
+ field the section to which the relocations apply;
+
+ - section with the SHF_INFO_LINK flag set to signal that `sh_info'
+ references a section. This allows correct handling of unknown
+ sections. */
+#define SH_INFO_LINK_P(Shdr) \
+ ((Shdr)->sh_type == SHT_REL || (Shdr)->sh_type == SHT_RELA \
+ || ((Shdr)->sh_flags & SHF_INFO_LINK) != 0)
+
+
+/* When combining ELF section flags we must distinguish two kinds:
+
+ - flags which cause problem if not added to the result even if not
+ present in all input sections
+
+ - flags which cause problem if added to the result if not present
+ in all input sections
+
+ The following definition is for the general case. There might be
+ machine specific extensions. */
+#define SH_FLAGS_COMBINE(Flags1, Flags2) \
+ (((Flags1 | Flags2) \
+ & (SHF_WRITE | SHF_ALLOC | SHF_EXECINSTR | SHF_LINK_ORDER \
+ | SHF_OS_NONCONFORMING | SHF_GROUP)) \
+ | (Flags1 & Flags2 & (SHF_MERGE | SHF_STRINGS | SHF_INFO_LINK)))
+
+/* Similar macro: return the bits of the flags which necessarily must
+ match if two sections are automatically combined. Sections still
+ can be forcefully combined in which case SH_FLAGS_COMBINE can be
+ used to determine the combined flags. */
+#define SH_FLAGS_IMPORTANT(Flags) \
+ ((Flags) & ~((GElf_Xword) 0 | SHF_LINK_ORDER | SHF_OS_NONCONFORMING))
+
+
+/* Size of an entry in the hash table. The ELF specification says all
+ entries are regardless of platform 32-bits in size. Early 64-bit
+ ports (namely Alpha for Linux) got this wrong. The wording was not
+ clear.
+
+ Several years later the ABI for the 64-bit S390s was developed.
+ Many things were copied from the IA-64 ABI (which uses the correct
+ 32-bit entry size) but what do these people do? They use 64-bit
+ entries. It is really shocking to see what kind of morons are out
+ there. And even worse: they are allowed to design ABIs. */
+#define SH_ENTSIZE_HASH(Ehdr) \
+ ((Ehdr)->e_machine == EM_ALPHA \
+ || ((Ehdr)->e_machine == EM_S390 \
+ && (Ehdr)->e_ident[EI_CLASS] == ELFCLASS64) ? 8 : 4)
+
+#endif /* elf-knowledge.h */