582 lines
18 KiB
C
582 lines
18 KiB
C
/* Internal interfaces for libelf.
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Copyright (C) 1998, 1999, 2000, 2001, 2002 Red Hat, Inc.
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Contributed by Ulrich Drepper <drepper@redhat.com>, 1998.
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This program is Open Source software; you can redistribute it and/or
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modify it under the terms of the Open Software License version 1.0 as
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published by the Open Source Initiative.
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You should have received a copy of the Open Software License along
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with this program; if not, you may obtain a copy of the Open Software
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License version 1.0 from http://www.opensource.org/licenses/osl.php or
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by writing the Open Source Initiative c/o Lawrence Rosen, Esq.,
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3001 King Ranch Road, Ukiah, CA 95482. */
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#ifndef _LIBELFP_H
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#define _LIBELFP_H 1
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#include <ar.h>
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#include <gelf.h>
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#include <stdint.h>
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#if defined(__LCLINT__)
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typedef int bool;
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#endif
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/* gettext helper macros. */
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#define _(Str) dgettext ("libelf", Str)
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/* Helper Macros to write 32 bit and 64 bit functions. */
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#define __elfw2_(Bits, Name) __elf##Bits##_##Name
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#define elfw2_(Bits, Name) elf##Bits##_##Name
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#define ElfW2_(Bits, Name) Elf##Bits##_##Name
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#define ELFW2_(Bits, Name) ELF##Bits##_##Name
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#define ELFW_(Name, Bits) Name##Bits
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#define __elfw2(Bits, Name) __elfw2_(Bits, Name)
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#define elfw2(Bits, Name) elfw2_(Bits, Name)
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#define ElfW2(Bits, Name) ElfW2_(Bits, Name)
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#define ELFW2(Bits, Name) ELFW2_(Bits, Name)
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#define ELFW(Name, Bits) ELFW_(Name, Bits)
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/* Sizes of the external types, for 32 bits objects. */
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#define ELF32_FSZ_ADDR 4
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#define ELF32_FSZ_OFF 4
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#define ELF32_FSZ_HALF 2
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#define ELF32_FSZ_WORD 4
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#define ELF32_FSZ_SWORD 4
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#define ELF32_FSZ_XWORD 8
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#define ELF32_FSZ_SXWORD 8
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/* Same for 64 bits objects. */
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#define ELF64_FSZ_ADDR 8
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#define ELF64_FSZ_OFF 8
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#define ELF64_FSZ_HALF 2
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#define ELF64_FSZ_WORD 4
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#define ELF64_FSZ_SWORD 4
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#define ELF64_FSZ_XWORD 8
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#define ELF64_FSZ_SXWORD 8
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/* This is an extension of the ELF_F_* enumeration. The values here are
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not part of the library interface, they are only used internally. */
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enum
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{
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ELF_F_MMAPPED = 0x40,
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ELF_F_MALLOCED = 0x80,
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ELF_F_FILEDATA = 0x100
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};
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/* Get definition of all the external types. */
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#include "exttypes.h"
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/* Error values. */
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enum
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{
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ELF_E_NOERROR = 0,
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ELF_E_UNKNOWN_ERROR,
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ELF_E_UNKNOWN_VERSION,
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ELF_E_UNKNOWN_TYPE,
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ELF_E_INVALID_HANDLE,
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ELF_E_SOURCE_SIZE,
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ELF_E_DEST_SIZE,
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ELF_E_INVALID_ENCODING,
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ELF_E_NOMEM,
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ELF_E_INVALID_FILE,
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ELF_E_INVALID_OP,
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ELF_E_NO_VERSION,
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ELF_E_INVALID_CMD,
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ELF_E_RANGE,
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ELF_E_ARCHIVE_FMAG,
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ELF_E_INVALID_ARCHIVE,
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ELF_E_NO_ARCHIVE,
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ELF_E_NO_INDEX,
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ELF_E_READ_ERROR,
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ELF_E_WRITE_ERROR,
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ELF_E_INVALID_CLASS,
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ELF_E_INVALID_INDEX,
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ELF_E_INVALID_OPERAND,
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ELF_E_INVALID_SECTION,
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ELF_E_INVALID_COMMAND,
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ELF_E_WRONG_ORDER_EHDR,
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ELF_E_FD_DISABLED,
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ELF_E_FD_MISMATCH,
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ELF_E_OFFSET_RANGE,
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ELF_E_NOT_NUL_SECTION,
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ELF_E_DATA_MISMATCH,
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ELF_E_INVALID_SECTION_HEADER,
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ELF_E_INVALID_DATA,
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ELF_E_DATA_ENCODING,
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ELF_E_SECTION_TOO_SMALL,
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ELF_E_INVALID_ALIGN,
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ELF_E_INVALID_SHENTSIZE,
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ELF_E_UPDATE_RO,
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ELF_E_NOFILE,
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ELF_E_GROUP_NOT_REL,
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ELF_E_INVALID_PHDR,
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/* Keep this as the last entry. */
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ELF_E_NUM
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};
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/* The visible `Elf_Data' type is not sufficent for some operations due
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to a misdesigned interface. Extend it for internal purposes. */
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typedef struct
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{
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Elf_Data d;
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Elf_Scn *s;
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} Elf_Data_Scn;
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/* List of `Elf_Data' descriptors. This is what makes up the section
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contents. */
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typedef struct Elf_Data_List
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{
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/* `data' *must* be the first element in the struct. */
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Elf_Data_Scn data;
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struct Elf_Data_List *next;
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int flags;
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} Elf_Data_List;
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/* Descriptor for ELF section. */
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struct Elf_Scn
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{
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/* We have to distinguish several different situations:
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1. the section is user created. Therefore there is no file or memory
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region to read the data from. Here we have two different subcases:
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a) data was not yet added (before the first `elf_newdata' call)
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b) at least one data set is available
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2. this is a section from a file/memory region. We have to read the
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current content in one data block if we have to. But we don't
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read the data until it is necessary. So we have the subcases:
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a) the section in the file has size zero (for whatever reason)
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b) the data of the file is not (yet) read
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c) the data is read and available.
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In addition to this we have different data sets, the raw and the converted
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data. This distinction only exists for the data read from the file.
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All user-added data set (all but the first when read from the file or
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all of them for user-create sections) are the same in both formats.
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We don't create the converted data before it is necessary.
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The `data_read' element signals whether data is available in the
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raw format.
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If there is data from the file/memory region or if read one data
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set is added the `rawdata_list_read' pointer in non-NULL and points
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to the last filled data set. `raw_datalist_rear' is therefore NULL
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only if there is no data set at all.
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This so far allows to distinguish all but two cases (given that the
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`rawdata_list' and `data_list' entries are initialized to zero) is
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between not yet loaded data from the file/memory region and a section
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with zero size and type ELF_T_BYTE. */
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Elf_Data_List data_list; /* List of data buffers. */
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Elf_Data_List *data_list_rear; /* Pointer to the rear of the data list. */
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Elf_Data_Scn rawdata; /* Uninterpreted data of the section. */
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int data_read; /* Nonzero if the section was created by the
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user or if the data from the file/memory
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is read. */
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size_t index; /* Index of this section. */
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struct Elf *elf; /* The underlying ELF file. */
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union
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{
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Elf32_Shdr *e32; /* Pointer to 32bit section header. */
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Elf64_Shdr *e64; /* Pointer to 64bit section header. */
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} shdr;
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unsigned int shdr_flags; /* Section header modified? */
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unsigned int flags; /* Section changed in size? */
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char *rawdata_base; /* The unmodified data of the section. */
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char *data_base; /* The converted data of the section. */
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struct Elf_ScnList *list; /* Pointer the the section list element the
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data is in. */
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};
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/* List of section. */
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typedef struct Elf_ScnList
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{
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unsigned int cnt; /* Number of elements of 'data' used. */
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unsigned int max; /* Number of elements of 'data' allocated. */
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struct Elf_ScnList *next; /* Next block of sections. */
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struct Elf_Scn data[0]; /* Section data. */
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} Elf_ScnList;
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/* The ELF descriptor. */
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struct Elf
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{
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/* What kind of file is underneath (ELF file, archive...). */
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Elf_Kind kind;
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/* Command used to create this descriptor. */
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Elf_Cmd cmd;
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/* The binary class. */
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unsigned int class;
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/* The used file descriptor. -1 if not available anymore. */
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int fildes;
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/* Offset in the archive this file starts or zero. */
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off_t start_offset;
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/* Size of the file in the archive or the entire file size, or ~0
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for an (yet) unknown size. */
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size_t maximum_size;
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/* Address to which the file was mapped. NULL if not mapped. */
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/*@null@*/
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void *map_address;
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/* Describes the way the memory was allocated and if the dirty bit is
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signalled it means that the whole file has to be rewritten since
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the layout changed. */
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int flags;
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/* When created for an archive member this points to the descriptor
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for the archive. */
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/*@null@*/
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Elf *parent;
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/* Lock to handle multithreaded programs. */
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rwlock_define (,lock);
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/* Reference counting for the descriptor. */
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int ref_count;
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struct Elf *next; /* Used in list of archive descriptors. */
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union
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{
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struct
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{
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int ehdr_flags; /* Flags (dirty) for ELF header. */
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int phdr_flags; /* Flags (dirty|malloc) for program header. */
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int shdr_malloced; /* Nonzero if shdr array was allocated. */
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/* The next fields are only useful when testing for ==/!= NULL. */
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void *ehdr;
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void *shdr;
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void *phdr;
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Elf_ScnList *scns_last; /* Last element in the section list.
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If NULL the data has not yet been
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read from the file. */
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unsigned int scnincr; /* Number of sections allocate the last
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time. */
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} elf;
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struct
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{
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int ehdr_flags; /* Flags (dirty) for ELF header. */
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int phdr_flags; /* Flags (dirty|malloc) for program header. */
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int shdr_malloced; /* Nonzero if shdr array was allocated. */
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Elf32_Ehdr *ehdr; /* Pointer to the ELF header. This is
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never malloced. */
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Elf32_Shdr *shdr; /* Used when reading from a file. */
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Elf32_Phdr *phdr; /* Pointer to the program header array. */
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Elf_ScnList *scns_last; /* Last element in the section list.
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If NULL the data has not yet been
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read from the file. */
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unsigned int scnincr; /* Number of sections allocate the last
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time. */
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Elf32_Ehdr ehdr_mem; /* Memory used for ELF header when not
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mmaped. */
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char __e32scnspad[sizeof (Elf64_Ehdr) - sizeof (Elf32_Ehdr)];
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/* The section array. */
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Elf_ScnList scns;
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} elf32;
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struct
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{
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int ehdr_flags; /* Flags (dirty) for ELF header. */
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int phdr_flags; /* Flags (dirty|malloc) for program header. */
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int shdr_malloced; /* Nonzero if shdr array was allocated. */
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Elf64_Ehdr *ehdr; /* Pointer to the ELF header. This is
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never malloced. */
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Elf64_Shdr *shdr; /* Used when reading from a file. */
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Elf64_Phdr *phdr; /* Pointer to the program header array. */
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Elf_ScnList *scns_last; /* Last element in the section list.
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If NULL the data has not yet been
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read from the file. */
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unsigned int scnincr; /* Number of sections allocate the last
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time. */
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Elf64_Ehdr ehdr_mem; /* Memory used for ELF header when not
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mmaped. */
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/* The section array. */
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Elf_ScnList scns;
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} elf64;
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struct
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{
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int has_index; /* Set when file has index. 0 means
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undecided, > 0 means it has one. */
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Elf_Arsym *ar_sym; /* Symbol table returned by elf_getarsym. */
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size_t ar_sym_num; /* Number of entries in `ar_sym'. */
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char *long_names; /* If no index is available but long names
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are used this elements points to the data.*/
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size_t long_names_len; /* Length of the long name table. */
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off_t offset; /* Offset in file we are currently at.
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elf_next() advances this to the next
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member of the archive. */
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Elf_Arhdr elf_ar_hdr; /* Structure returned by 'elf_getarhdr'. */
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struct ar_hdr ar_hdr; /* Header read from file. */
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char ar_name[16]; /* NUL terminated ar_name of elf_ar_hdr. */
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char raw_name[17]; /* This is a buffer for the NUL terminated
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named raw_name used in the elf_ar_hdr. */
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struct Elf *children; /* List of all descriptors for this archive. */
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} ar;
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} state;
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/* There absolutely never must be anything following the union. */
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};
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/* Type of the conversion functions. These functions will convert the
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byte order. */
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typedef void (*xfct_t) (void *, const void *, size_t, int)
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/*@*/;
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/* The table with the function pointers. */
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/*@unchecked@*/
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extern const xfct_t __elf_xfctstom[EV_NUM - 1][EV_NUM - 1][ELFCLASSNUM - 1][ELF_T_NUM] attribute_hidden;
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/*@unchecked@*/
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extern const xfct_t __elf_xfctstof[EV_NUM - 1][EV_NUM - 1][ELFCLASSNUM - 1][ELF_T_NUM] attribute_hidden;
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/* Array with sizes of the external types indexed by ELF version, binary
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class, and type. */
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/*@unchecked@*/
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extern const size_t __libelf_type_sizes[EV_NUM - 1][ELFCLASSNUM - 1][ELF_T_NUM] attribute_hidden;
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/* We often have to access the size for a type in the current version. */
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#if EV_NUM != 2
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# define elf_typesize(class,type,n) \
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elfw2(class,fsize) (type, n, __libelf_version)
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#else
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# define elf_typesize(class,type,n) \
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(__libelf_type_sizes[EV_CURRENT - 1][ELFW(ELFCLASS,class) - 1][type] * n)
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#endif
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/* Currently selected version of the ELF specification. */
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/*@unchecked@*/
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extern unsigned int __libelf_version attribute_hidden;
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/* The byte value used for filling gaps. */
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/*@unchecked@*/
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extern int __libelf_fill_byte attribute_hidden;
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/* Nonzero if the version was set. */
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/*@unchecked@*/
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extern int __libelf_version_initialized attribute_hidden;
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/* The libelf API does not have such a function but it is still useful.
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Get the memory size for the given type.
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These functions cannot be marked internal since they are aliases
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of the export elfXX_fsize functions.*/
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extern size_t __elf32_msize (Elf_Type __type, size_t __count,
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unsigned int __version)
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/*@*/;
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extern size_t __elf64_msize (Elf_Type __type, size_t __count,
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unsigned int __version)
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/*@*/;
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/* Create Elf descriptor from memory image. */
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/*@null@*/
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extern Elf *__libelf_read_mmaped_file (int fildes, void *map_address,
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off_t offset, size_t maxsize,
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Elf_Cmd cmd, /*@null@*/ Elf *parent)
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internal_function
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/*@*/;
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/* Set error value. */
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extern void __libelf_seterrno (int value) internal_function
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/*@globals internalState @*/
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/*@modifies internalState @*/;
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/* Get the next archive header. */
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extern int __libelf_next_arhdr (Elf *elf) internal_function
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/*@modifies elf @*/;
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/* Read all of the file associated with the descriptor. */
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/*@null@*/
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extern char *__libelf_readall (Elf *elf) internal_function
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/*@modifies elf @*/;
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/* Read the complete section table and convert the byte order if necessary. */
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extern int __libelf_readsections (Elf *elf) internal_function
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/*@*/;
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/* Store the information for the raw data in the `rawdata_list' element. */
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extern int __libelf_set_rawdata (Elf_Scn *scn) internal_function
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/*@modifies scn @*/;
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/* Helper functions for elf_update. */
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extern off_t __elf32_updatenull (Elf *elf, int *change_bop, size_t shnum)
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internal_function
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/*@modifies elf, *change_bop @*/;
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extern off_t __elf64_updatenull (Elf *elf, int *change_bop, size_t shnum)
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internal_function
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/*@modifies elf, *change_bop @*/;
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extern int __elf32_updatemmap (Elf *elf, int change_bo, size_t shnum)
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internal_function
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/*@modifies elf @*/;
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extern int __elf64_updatemmap (Elf *elf, int change_bo, size_t shnum)
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internal_function
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/*@modifies elf @*/;
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extern int __elf32_updatefile (Elf *elf, int change_bo, size_t shnum)
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internal_function
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/*@modifies elf @*/;
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extern int __elf64_updatefile (Elf *elf, int change_bo, size_t shnum)
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internal_function
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/*@modifies elf @*/;
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/* Alias for exported functions to avoid PLT entries. */
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extern Elf *__elf_begin_internal (int __fildes, Elf_Cmd __cmd, Elf *__ref)
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attribute_hidden
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/*@*/;
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extern Elf32_Ehdr *__elf32_getehdr_internal (Elf *__elf) attribute_hidden
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/*@*/;
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extern Elf64_Ehdr *__elf64_getehdr_internal (Elf *__elf) attribute_hidden
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/*@*/;
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extern Elf32_Ehdr *__elf32_newehdr_internal (Elf *__elf) attribute_hidden
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/*@*/;
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extern Elf64_Ehdr *__elf64_newehdr_internal (Elf *__elf) attribute_hidden
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/*@*/;
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extern Elf32_Phdr *__elf32_getphdr_internal (Elf *__elf) attribute_hidden
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/*@*/;
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extern Elf64_Phdr *__elf64_getphdr_internal (Elf *__elf) attribute_hidden
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/*@*/;
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extern Elf32_Phdr *__elf32_newphdr_internal (Elf *__elf, size_t __cnt)
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attribute_hidden
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/*@*/;
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extern Elf64_Phdr *__elf64_newphdr_internal (Elf *__elf, size_t __cnt)
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attribute_hidden
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/*@*/;
|
|
extern int __elf_getshnum_internal (Elf *__elf, size_t *__dst)
|
|
attribute_hidden
|
|
/*@*/;
|
|
extern int __elf_getshstrndx_internal (Elf *__elf, size_t *__dst)
|
|
attribute_hidden
|
|
/*@*/;
|
|
extern Elf32_Shdr *__elf32_getshdr_internal (Elf_Scn *__scn) attribute_hidden
|
|
/*@*/;
|
|
extern Elf64_Shdr *__elf64_getshdr_internal (Elf_Scn *__scn) attribute_hidden
|
|
/*@*/;
|
|
extern Elf_Scn *__elf_getscn_internal (Elf *__elf, size_t __index)
|
|
attribute_hidden
|
|
/*@*/;
|
|
extern Elf_Scn *__elf_nextscn_internal (Elf *__elf, Elf_Scn *__scn)
|
|
attribute_hidden
|
|
/*@*/;
|
|
extern Elf_Data *__elf_getdata_internal (Elf_Scn *__scn, Elf_Data *__data)
|
|
attribute_hidden
|
|
/*@*/;
|
|
extern Elf_Data *__elf_rawdata_internal (Elf_Scn *__scn, Elf_Data *__data)
|
|
attribute_hidden
|
|
/*@*/;
|
|
extern char *__elf_strptr_internal (Elf *__elf, size_t __index,
|
|
size_t __offset) attribute_hidden
|
|
/*@*/;
|
|
extern Elf_Data *__elf32_xlatetom_internal (Elf_Data *__dest,
|
|
const Elf_Data *__src,
|
|
unsigned int __encode)
|
|
attribute_hidden
|
|
/*@*/;
|
|
extern Elf_Data *__elf64_xlatetom_internal (Elf_Data *__dest,
|
|
const Elf_Data *__src,
|
|
unsigned int __encode)
|
|
attribute_hidden
|
|
/*@*/;
|
|
extern Elf_Data *__elf32_xlatetof_internal (Elf_Data *__dest,
|
|
const Elf_Data *__src,
|
|
unsigned int __encode)
|
|
attribute_hidden
|
|
/*@*/;
|
|
extern Elf_Data *__elf64_xlatetof_internal (Elf_Data *__dest,
|
|
const Elf_Data *__src,
|
|
unsigned int __encode)
|
|
attribute_hidden
|
|
/*@*/;
|
|
extern unsigned int __elf_version_internal (unsigned int __version)
|
|
attribute_hidden
|
|
/*@*/;
|
|
extern unsigned long int __elf_hash_internal (const char *__string)
|
|
__attribute__ ((__pure__, visibility ("hidden")))
|
|
/*@*/;
|
|
extern long int __elf32_checksum_internal (Elf *__elf) attribute_hidden
|
|
/*@*/;
|
|
extern long int __elf64_checksum_internal (Elf *__elf) attribute_hidden
|
|
/*@*/;
|
|
|
|
|
|
extern size_t __gelf_fsize_internal (Elf *__elf, Elf_Type __type,
|
|
size_t __count, unsigned int __version)
|
|
attribute_hidden
|
|
/*@*/;
|
|
extern GElf_Shdr *__gelf_getshdr_internal (Elf_Scn *__scn, GElf_Shdr *__dst)
|
|
attribute_hidden
|
|
/*@*/;
|
|
extern GElf_Sym *__gelf_getsym_internal (Elf_Data *__data, int __ndx,
|
|
GElf_Sym *__dst) attribute_hidden
|
|
/*@*/;
|
|
|
|
|
|
extern uint32_t __libelf_crc32 (uint32_t crc, unsigned char *buf, size_t len)
|
|
attribute_hidden;
|
|
|
|
|
|
/* We often have to update a flag iff a value changed. Make this
|
|
convenient. None of the parameters must have a side effect. */
|
|
#ifdef __GNUC__
|
|
# define update_if_changed(var, exp, flag) \
|
|
do { \
|
|
__typeof__ (var) *_var = &(var); \
|
|
__typeof__ (exp) _exp = (exp); \
|
|
if (*_var != _exp) \
|
|
{ \
|
|
*_var = _exp; \
|
|
(flag) |= ELF_F_DIRTY; \
|
|
} \
|
|
} while (0)
|
|
#else
|
|
# define update_if_changed(var, exp, flag) \
|
|
do { \
|
|
if ((var) != (exp)) \
|
|
{ \
|
|
(var) = (exp); \
|
|
(flag) |= ELF_F_DIRTY; \
|
|
} \
|
|
} while (0)
|
|
#endif
|
|
|
|
#endif /* libelfP.h */
|