bintools/elftools/inc/elfdefs.h
changeset 0 044383f39525
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/bintools/elftools/inc/elfdefs.h	Tue Oct 27 16:36:35 2009 +0000
@@ -0,0 +1,819 @@
+/*
+* Copyright (c) 2001-2009 Nokia Corporation and/or its subsidiary(-ies).
+* All rights reserved.
+* This component and the accompanying materials are made available
+* under the terms of the License "Eclipse Public License v1.0"
+* which accompanies this distribution, and is available
+* at the URL "http://www.eclipse.org/legal/epl-v10.html".
+*
+* Initial Contributors:
+* Nokia Corporation - initial contribution.
+*
+* Contributors:
+*
+* Description: 
+* lifted from the ARMELF spec
+*
+*/
+
+
+#ifndef __ELFDEFS_H__
+#define __ELFDEFS_H__
+
+
+// ARMELF 3.1.2
+// Data Representation
+typedef unsigned int Elf32_Addr;     //Unsigned program address
+typedef unsigned short Elf32_Half;   //Unsigned medium integer
+typedef unsigned int Elf32_Off;      //Unsigned file offset
+typedef signed int Elf32_Sword;      //Signed large integer
+typedef unsigned int Elf32_Word;     //Unsigned large integer
+typedef unsigned char UChar;         //Unsigned small integer
+
+typedef char* MemAddr;
+/*
+3.2 ELF Header 
+Some object file control structures can grow, because the ELF header
+contains their actual sizes. If the object file format changes, a
+program may encounter control structures that are larger or smaller
+than expected. Programs might therefore ignore extra information. The
+treatment of missing information depends on context and will be
+specified when and if extensions are defined.
+*/
+#define EI_NIDENT 16
+typedef struct {
+
+  // marks the file as an object file and provide machine-independent 
+  // data with which to decode and interpret the file's contents.
+  unsigned char e_ident[EI_NIDENT];
+
+  // identifies the object file type.
+  Elf32_Half e_type;
+
+  // specifies the required architecture for an individual file.
+  Elf32_Half e_machine;
+
+  // identifies the object file version.
+  Elf32_Word e_version;
+
+  // gives the virtual address to which the system first transfers 
+  // control, thus starting the process. If the file has no associated
+  // entry point, this member holds zero.
+  Elf32_Addr e_entry;
+
+  // holds the program header table's file offset in bytes. If the 
+  // file has no program header table, this member holds zero.
+  Elf32_Off e_phoff;
+
+  // holds the section header table's file offset in bytes. If the 
+  // file has no section header table, this member holds zero.
+  Elf32_Off e_shoff;
+
+  // holds processor-specific flags associated with the file. Flag 
+  // names take the form EF_machine_flag.
+  Elf32_Word e_flags;
+
+  // holds the ELF header's size in bytes.
+  Elf32_Half e_ehsize;
+
+  // holds the size in bytes of one entry in the file's program 
+  // header table; all entries are the same size.
+  Elf32_Half e_phentsize;
+
+  // holds the number of entries in the program header table. 
+  // Thus the product of e_phentsize and e_phnum gives the table's 
+  // size in bytes. If a file has no program header table, e_phnum
+  // holds the value zero.
+  Elf32_Half e_phnum;
+
+  // holds a section header's size in bytes. A section header is 
+  // one entry in the section header table; all entries are the same size.
+  Elf32_Half e_shentsize;
+
+  // holds the number of entries in the section header table. Thus 
+  // the product of e_shentsize and e_shnum gives the section header 
+  // table's size in bytes. If a file has no section header table, 
+  // e_shnum holds the value zero.
+  Elf32_Half e_shnum;
+
+  // holds the section header table index of the entry associated 
+  // with the section name string table. If the file has no section 
+  // name string table, this member holds the value SHN_UNDEF. 
+  Elf32_Half e_shstrndx;
+
+} Elf32_Ehdr;
+
+// values for e_type
+#define ET_NONE 	0 // No file type
+#define ET_REL 		1 // Re-locatable
+#define ET_EXEC 	2 // Executable file
+#define ET_DYN 		3 // Shared object
+#define ET_CORE 	4 // Core file
+#define ET_LOPROC  0xff00 // Processor-specific
+#define ET_HIPROC  0xffff // Processor-specific
+
+//values for e_machine
+#define EM_NONE 	0 // No machine
+#define EM_M32 		1 // AT&T WE 32100
+#define EM_SPARC 	2 // SPARC
+#define EM_386 		3 // Intel Architecture
+#define EM_68K 		4 // Moto 68000
+#define EM_88K 		5 // Moto 88000
+#define EM_860 		7 // Intel 80860
+#define EM_MIPS 	8 // MIPS RS3000 Big-Endian
+#define EM_MIPS_RS4_BE 10 // MIPS RS4000 Big-Endian
+//#define RESERVED 11-16 Reserved for future use
+#define EM_ARM 	       40 //ARM/Thumb Architecture
+
+// values for e_version
+#define EV_NONE 	0 // Invalid version
+#define EV_CURRENT 	1 // Current version
+
+// ELF Identification
+#define EI_MAG0 	0 // File identification
+#define EI_MAG1 	1 // File identification
+#define EI_MAG2 	2 // File identification
+#define EI_MAG3 	3 // File identification
+#define EI_CLASS 	4 // File class
+#define EI_DATA 	5 // Data encoding
+#define EI_VERSION 	6 // File version
+#define EI_PAD 		7 // Start of padding bytes
+
+// values for e_ident[0-3]
+#define ELFMAG0        0x7f // e_ident[EI_MAG0]
+#define ELFMAG1 	'E' // e_ident[EI_MAG1]
+#define ELFMAG2 	'L' // e_ident[EI_MAG2]
+#define ELFMAG3 	'F' // e_ident[EI_MAG3]
+
+// values for e_ident[EI_CLASS]- identifies the file's class, or capacity.
+#define ELFCLASSNONE 	0 // Invalid class
+#define ELFCLASS32 	1 // 32-bit objects
+#define ELFCLASS64 	2 // 64-bit objects
+
+// values for e_ident[EI_DATA] - specifies the data encoding of the 
+// processor-specific data in the object file. 
+#define ELFDATANONE 	0 // Invalid data encoding
+#define ELFDATA2LSB 	1 // 2's complement , with LSB at lowest address.
+#define ELFDATA2MSB 	2 // 2's complement , with MSB at lowest address.
+
+// ARM/THUMB specific values for e_flags
+
+// e_entry contains a program-loader entry point
+#define EF_ARM_HASENTRY 0x02
+// Each subsection of the symbol table is sorted by symbol value
+#define EF_ARM_SYMSARESORTED 0x04
+// Symbols in dynamic symbol tables that are defined in sections
+// included in program segment n have st_shndx = n+ 1. 
+#define EF_ARM_DYNSYMSUSESEGIDX 0x8
+// Mapping symbols precede other local symbols in the symbol table
+#define EF_ARM_MAPSYMSFIRST 0x10
+// This masks an 8-bit version number, the version of the ARM EABI to
+// which this ELF file conforms. This EABI is version 2. A value of 0
+// denotes unknown conformance. (current version is 0x02000000)
+#define EF_ARM_EABIMASK 0xFF000000
+
+#define EF_ARM_EABI_VERSION 0x02000000
+#define EF_ARM_BPABI_VERSION 0x04000000
+
+/* 
+3.3 Sections
+
+An object file's section header table lets one locate all the file's
+sections. The section header table is an array of Elf32_Shdr
+structures as described below. A section header table index is a
+subscript into this array. The ELF header's e_shoff member gives the
+byte offset from the beginning of the file to the section header
+table; e_shnum tells how many entries the section header table
+contains; e_shentsize gives the size in bytes of each entry.
+*/
+
+// Some section header table indexes are reserved; an object file will
+// not have sections for these special indexes.
+
+// marks an undefined, missing, irrelevant, or otherwise meaningless 
+// section reference.
+#define SHN_UNDEF 	0
+// specifies the lower bound of the range of reserved indexes.
+#define SHN_LORESERVE 	0xff00
+// SHN_LOPROC-SHN_HIPRO - this inclusive range reserved for 
+// processor-specific semantics.
+#define SHN_LOPROC 	0xff00
+#define SHN_HIPROC 	0xff1f
+// Specifies absolute values for the corresponding reference. 
+// For example, symbols defined relative to section number SHN_ABS have 
+// absolute values and are not affected by relocation.
+#define SHN_ABS 	0xfff1
+// Symbols defined relative to this section are common symbols, 
+// such as FORTRAN COMMON or unallocated C external variables.
+#define SHN_COMMON 	0xfff2
+// specifies the upper bound of the range of reserved indexes.
+#define SHN_HIRESERVE 	0xffff
+
+typedef struct {
+
+  // specifies the name of the section. Its value is an index into the
+  // section header string table section [see String Tablebelow],
+  // giving the location of a null-terminated string.
+  Elf32_Word sh_name;
+
+  // categorizes the section's contents and semantics. Section types
+  // and their descriptions appear below.
+  Elf32_Word sh_type;
+
+  // Sections support 1-bit flags that describe miscellaneous
+  // attributes. Flag definitions appear below.
+  Elf32_Word sh_flags;
+
+  // If the section will appear in the memory image of a process, this
+  // member gives the address at which the section's first byte should
+  // reside. Otherwise, the member contains 0.
+  Elf32_Addr sh_addr;
+
+  // gives the byte offset from the beginning of the file to the first
+  // byte in the section.One section type, SHT_NOBITS described below,
+  // occupies no space in the file, and its sh_offset member locates
+  // the conceptual placement in the file.
+  Elf32_Off sh_offset;
+
+  // gives the section's size in bytes. Unless the section type is
+  // SHT_NOBITS, the section occupies sh_size bytes in the file. A
+  // section of type SHT_NOBITS may have a non-zero size, but it
+  // occupies no space in the file.
+  Elf32_Word sh_size;
+
+  // holds a section header table index link, whose interpretation
+  // depends on the section type. A table below describes the values.
+  Elf32_Word sh_link;
+
+  // holds extra information, whose interpretation depends on the
+  // section type. A table below describes the values.
+  Elf32_Word sh_info;
+
+  // Some sections have address alignment constraints. For example, if
+  // a section holds a doubleword, the system must ensure double-word
+  // alignment for the entire section. That is, the value of sh_addr
+  // must be congruent to 0, modulo the value of
+  // sh_addralign. Currently, only 0 and positive integral powers of
+  // two are allowed. Values 0 and 1 mean the section has no alignment
+  // constraints.
+  Elf32_Word sh_addralign;
+
+  // Some sections hold a table of fixed-size entries, such as a
+  // symbol table. For such a section, this member gives the size in
+  // bytes of each entry. The member contains 0 if the section does
+  // not hold a table of fixedsize entries. A section header's sh_type
+  // member specifies the section's semantics.
+  Elf32_Word sh_entsize;
+
+} Elf32_Shdr;
+
+// values for sh_type 
+
+#define SHT_NULL 0 // marks the section header as inactive; it does
+ // not have an associated section. Other members of the section
+ // header have undefined values.
+#define SHT_PROGBITS 1 // The section holds information defined by the
+ // program, whose format and meaning are determined solely by the
+ // program.
+#define SHT_SYMTAB 2 //These sections hold a symbol table.
+#define SHT_STRTAB 3 // The section holds a string table.
+#define SHT_RELA 4 // The section holds relocation entries with
+ // explicit addends, such as type Elf32_Rela for the 32-bit class of
+ // object files. An object file may have multiple relocation
+ // sections. See Relocationbelow for details.
+#define SHT_HASH 5 // The section holds a symbol hash table.
+#define SHT_DYNAMIC 6 // The section holds information for dynamic
+ // linking.
+#define SHT_NOTE 7 // This section holds information that marks the
+ // file in some way.
+#define SHT_NOBITS 8 // A section of this type occupies no space in
+ // the file but otherwise resembles SHT_PROGBITS. Although this
+ // section contains no bytes, the sh_offset member contains the
+ // conceptual file offset.
+#define SHT_REL 9 // The section holds relocation entries without
+ // explicit addends, such as type Elf32_Rel for the 32-bit class of
+ // object files. An object file may have multiple relocation
+ // sections. See Relocationbelow for details.
+#define SHT_SHLIB 10 // This section type is reserved but has
+ // unspecified semantics.
+#define SHT_DYNSYM 11 // This section hold dynamic symbol information
+// SHT_LOPROC through SHT_HIPROC - Values in this inclusive range are
+// reserved for processor-specific semantics.
+#define SHT_LOPROC     0x70000000
+#define SHT_ARM_EXIDX  0x70000001
+#define SHT_HIPROC     0x7fffffff
+// Section types between SHT_LOUSER and SHT_HIUSER may be used by the
+// application, without conflicting with current or future
+// system-defined section types.
+#define SHT_LOUSER 0x80000000 // This value specifies the lower bound
+ // of the range of indexes reserved for application programs.
+#define SHT_HIUSER 0xffffffff // This value specifies the upper bound
+ // of the range of indexes reserved for application programs.
+
+// values for sh_flags
+
+// The section contains data that should be writable during process execution
+#define SHF_WRITE 0x1 
+// The section occupies memory during process execution. Some control
+// sections do not reside in the memory image of an object file; this
+// attribute is off for those sections
+#define SHF_ALLOC 0x2 
+// The section contains executable machine instructions.
+#define SHF_EXECINSTR 0x4 
+// Bits in this mask are reserved for processor-specific semantics.
+#define SHF_MASKPROC 0xf0000000 
+
+
+typedef struct {
+
+  // holds an index into the object file's symbol string table, which
+  // holds the character representations of the symbol names.
+  Elf32_Word st_name;
+
+  // gives the value of the associated symbol. Depending on the
+  // context this may be an absolute value, an address, and so on
+  Elf32_Addr st_value;
+
+  // Many symbols have associated sizes. For example, a data object's
+  // size is the number of bytes contained in the object. This member
+  // holds 0 if the symbol has no size or an unknown size.
+  Elf32_Word st_size;
+
+  // This member specifies the symbol's type and binding
+  // attributes. The following code shows how to manipulate the
+  // values.
+#define ELF32_ST_BIND(i) ((i)>>4)
+#define ELF32_ST_TYPE(i) ((i)&0xf)
+#define ELF32_ST_INFO(b,t) (((b)<<4)+((t)&0xf))
+  unsigned char st_info;
+
+  // This member currently holds 0 and has no defined meaning.
+  unsigned char st_other;
+
+
+#define ELF32_ST_VISIBILITY(o)       ((o)&0x3)
+#define ELF64_ST_VISIBILITY(o)       ((o)&0x3)
+
+  // Every symbol table entry is defined in relation to some section;
+  // this member holds the relevant section header table index.
+  Elf32_Half st_shndx;
+
+} Elf32_Sym;
+
+// Local symbols are not visible outside the object file containing
+// their definition. Local symbols of the same name may exist in
+// multiple files without interfering with each other.
+#define STB_LOCAL 0
+// Global symbols are visible to all object files being combined. One
+// file's definition of a global symbol will satisfy another file's
+// undefined reference to the same global symbol.
+#define STB_GLOBAL 1
+// Weak symbols resemble global symbols, but their definitions have
+// lower precedence. Undefined weak symbols (weak references) may have
+// processor- or OS-specific semantics
+#define STB_WEAK 2 
+// STB_LOPROC through STB_HIPROC - values in this inclusive range are
+// reserved for processor-specific semantics.
+#define STB_LOPROC 13 
+#define STB_HIPROC 15
+
+// The symbol's type is not specified.
+#define STT_NOTYPE 0 
+// The symbol is associated with a data object, such as a variable, an
+// array, and so on.
+#define STT_OBJECT 1 
+// The symbol is associated with a function or other executable code.
+#define STT_FUNC 2 
+// The symbol is associated with a section. Symbol table entries of
+// this type exist primarily for relocation and normally have
+// STB_LOCAL binding.
+#define STT_SECTION 3 
+// A file symbol has STB_LOCAL binding, its section index is SHN_A BS,
+// and it precedes the other STB_LOCAL symbols for the file, if it is
+// present.
+#define STT_FILE 4 
+// Values in this inclusive range are reserved for processor-specific
+// semantics. If a symbol's value refers to a specific location within
+// a section, its section index member, st_shndx, holds an index into
+// the section header table. As the section moves during relocation,
+// the symbol's value changes as well, and references to the symbol
+// continue to point to the same location in the program. Some special
+// section index values give other semantics.
+#define STT_LOPROC 13
+#define STT_HIPROC 15
+
+/*
+STV_DEFAULT
+The visibility of symbols with the STV_DEFAULT attribute is as specified by the symbol's 
+binding type. That is, global and weak symbols are visible outside of their defining 
+component, the executable file or shared object. Local symbols are hidden. Global and weak
+ symbols can also be preempted, that is, they may by interposed by definitions of the same
+ name in another component. 
+
+STV_PROTECTED
+A symbol defined in the current component is protected if it is visible in other components
+ but cannot be preempted. Any reference to such a symbol from within the defining component
+ must be resolved to the definition in that component, even if there is a definition in
+ another component that would interpose by the default rules. A symbol with STB_LOCAL binding
+ will not have STV_PROTECTED visibility.
+
+STV_HIDDEN
+A symbol defined in the current component is hidden if its name is not visible to other
+ components. Such a symbol is necessarily protected. This attribute is used to control 
+ the external interface of a component. An object named by such a symbol may still be 
+ referenced from another component if its address is passed outside.
+
+A hidden symbol contained in a relocatable object is either removed or converted to 
+STB_LOCAL binding by the link-editor when the relocatable object is included in an
+ executable file or shared object.
+
+STV_INTERNAL
+This visibility attribute is currently reserved.
+*/
+#define STV_DEFAULT		0
+#define STV_INTERNAL	1
+#define STV_HIDDEN		2
+#define	STV_PROTECTED	3
+
+// Relocation Entries
+
+typedef struct { 
+
+  // r_offset gives the location at which to apply the relocation
+  // action. For a relocatable file, the value is the byte offset from
+  // the beginning of the section to the storage unit affected by the
+  // relocation. For an executable file or a shared object, the value
+  // is the virtual address of the storage unit affected by the
+  // relocation.
+  Elf32_Addr r_offset;
+
+  // r_info gives both the symbol table index with respect to which
+  // the relocation must be made, and the type of relocation to
+  // apply. For example, a call instruction's relocation entry would
+  // hold the symbol table index of the function being called. If the
+  // index is STN_UNDEF, the undefined symbol index, the relocation
+  // uses 0 as the symbol value. Relocation types are
+  // processor-specific; descriptions of their behavior appear in
+  // section 4.5, Relocation types. When the text in section 4.5
+  // refers to a relocation entry's relocation type or symbol table
+  // index, it means the result of applying ELF32_R_TYPE or
+  // ELF32_R_SYM, respectively, to the entry's r_info member.
+
+#define ELF32_R_SYM(i) ((i)>>8)
+#define ELF32_R_TYPE(i) ((unsigned char)(i))
+#define ELF32_R_INFO(s,t) (((s)<<8)+(unsigned char)(t))
+
+  Elf32_Word r_info; 
+} Elf32_Rel; 
+
+typedef struct {
+  Elf32_Addr r_offset;
+  Elf32_Word r_info;
+  Elf32_Sword r_addend;
+} Elf32_Rela;
+
+// Program Header
+
+typedef struct {
+
+  // p_type tells what kind of segment this array element describes or
+  // how to interpret the array element's information. Type values and
+  // their meanings are given below.
+  Elf32_Word p_type;
+
+  // p_offset gives the offset from the start of the file at which the
+  // first byte of the segment resides.
+  Elf32_Off p_offset;
+
+  // p_vaddr gives the virtual address at which the first byte of the
+  // segment resides in memory.
+  Elf32_Addr p_vaddr;
+
+  // p_paddr - On systems for which physical addressing is relevant,
+  // this member is reserved for the segment's physical address. This
+  // member requires operating system specific information.
+  Elf32_Addr p_paddr;
+
+  // p_filesz gives the number of bytes in the file image of the
+  // segment; it may be zero.
+  Elf32_Word p_filesz;
+
+  // p_memsz gives the number of bytes in the memory image of the
+  // segment; it may be zero.
+  Elf32_Word p_memsz;
+
+  // p_flags gives flags relevant to the segment. Defined flag values
+  // are given below.
+  Elf32_Word p_flags;
+
+  // p_align - Loadable process segments must have congruent values
+  // for p_vaddr and p_offset, modulo the page size. This member gives
+  // the value to which the segments are aligned in memory and in the
+  // file. Values 0 and 1 mean that no alignment is
+  // required. Otherwise, p_align should be a positive, integral power
+  // of 2, and p_vaddr should equal p_offset, modulo p_align.
+  Elf32_Word p_align;
+
+} Elf32_Phdr;
+
+// Segment types - values for p_type
+
+// The array element is unused; other members' values are
+// undefined. This type lets the program header table have ignored
+// entries.
+#define PT_NULL 0 
+// The array element specifies a loadable segment, described by
+// p_filesz and p_memsz (for additional explanation, see
+// PT_LOAD below).
+#define PT_LOAD 1 
+// The array element specifies dynamic linking information. See
+// subsection 4.7.
+#define PT_DYNAMIC 2 
+// The array element specifies the location and size of a
+// null-terminated pathname to invoke as an interpreter.
+#define PT_INTERP 3 
+// The array element specifies the location and size of auxiliary
+// information.
+#define PT_NOTE 4 
+// This segment type is reserved but has unspecified semantics.
+#define PT_SHLIB 5 
+// The array element, if present, specifies the location and size of
+// the program header table itself (for additional explanation, see
+// PT_ PHDR below).
+#define PT_PHDR 6 
+// Values in the inclusive [PT_LOPROC, PT_HIPROC] range are reserved
+// for processor-specific semantics.
+#define PT_LOPROC 0x70000000
+#define PT_HIPROC 0x7fffffff
+
+// values for p_flags
+// The segment may be executed.
+#define PF_X 1 
+// The segment may be written to.
+#define PF_W 2 
+// The segment may be read.
+#define PF_R 4 
+// Reserved for processor-specific purposes (see 4.6, Program
+// headers).
+#define PF_MASKPROC 0xf0000000 
+#define PF_ARM_ENTRY 0x80000000
+
+
+// Relocation types
+
+// ELF defines two sorts of relocation directive, SHT_REL, and
+// SHT_RELA. Both identify:
+//
+// o A section containing the storage unit - byte, half-word, word, or
+//   instruction - being relocated.
+// o An offset within the section - or the address within an
+//   executable program - of the storage unit itself.
+// o A symbol,the value of which helps to define a new value for the
+//   storage unit.
+// o A relocation typethat defines the computation to be
+//   performed. Computations are performed using 2's complement, 32-bit,
+//   unsigned arithmetic with silent overflow.
+// o An addend, that also helps to define a new value for the storage
+//   unit.
+//
+// The addend may be encoded wholly in a field of the storage unit
+// being relocated - relocation sort SHT_REL - or partly there and
+// partly in the addendfield of the relocation directive - relocation
+// sort SHT_RELA. Tables below describe the computation associated
+// with each relocation type, using the following notation:
+//
+// A - denotes the addend used to compute the new value of the storage
+//     unit being relocated.
+//   - It is the value extracted from the storage unit being relocated
+//     (relocation directives of sort SHT_REL) or the sum of that
+//     value and the r_addend field of the relocation directive (sort
+//     SHT_RELA).
+//   - If it has a unit, the unit is bytes. An encoded address or
+//     offset value is converted to bytes on extraction from a storage
+//     unit and re-encoded on insertion into a storage unit.
+//
+// P - denotes the place (section offset or address of the storage
+//     unit) being re-located. It is the sum of the r_offset field of
+//     the relocation directive and the base address of the section
+//     being re-located.
+//
+// S - denotes the value of the symbol whose symbol table index is
+//     given in the r_info field of the relocation directive.
+//
+// B - denotes the base address of the consolidated section in which
+//     the symbol is defined. For relocations of type R_ARM_SBREL32,
+//     this is the least static data address (the static base).
+//
+// relocation types 0-16 are generic
+//      Name             Type    Field                  Computation
+//====================================================================
+#define R_ARM_NONE         0  // Any                    No relocation. 
+#define R_ARM_PC24         1  // ARM B/BL               S - P + A
+#define R_ARM_ABS32        2  // 32-bit word            S + A
+#define R_ARM_REL32        3  // 32-bit word            S - P + A
+#define R_ARM_PC13         4  // ARM LDR r, [pc,...]    S - P + A
+#define R_ARM_ABS16        5  // 16-bit half-word       S + A
+#define R_ARM_ABS12        6  // ARM LDR/STR            S + A
+#define R_ARM_THM_ABS5     7  // Thumb LDR/STR          S + A
+#define R_ARM_ABS8         8  // 8-bit byte             S + A
+#define R_ARM_SBREL32      9  // 32-bit word            S - B + A
+#define R_ARM_THM_PC22    10  // Thumb BL pair          S - P + A
+#define R_ARM_THM_PC8     11  // Thumb LDR r, [pc,...]  S - P + A
+#define R_ARM_AMP_VCALL9  12  // AMP VCALL              Obsolete - SA-1500
+#define R_ARM_SWI24       13  // ARM SWI                S + A
+#define R_ARM_THM_SWI8    14  // Thumb SWI              S + A
+#define R_ARM_XPC25       15  // ARM BLX                S - P + A
+#define R_ARM_THM_XPC22   16  // Thumb BLX pair         S - P + A
+
+// relocation types 17-31 are reserved for ARM Linux
+#define R_ARM_GLOB_DAT    21  //  PLT related			S + A
+#define R_ARM_JUMP_SLOT   22  //  PLT related			S + A
+#define R_ARM_RELATIVE	  23  //  32-bit word			B(S) + A
+
+#define R_ARM_GOT_BREL	  26  //  			
+
+#define R_ARM_ALU_PCREL_7_0   32 // ARM ADD/SUB         (S - P + A) & 0x000000FF
+#define R_ARM_ALU_PCREL_15_8  33 // ARM ADD/SUB         (S - P + A) & 0x0000FF00
+#define R_ARM_ALU_PCREL_23_15 34 // ARM ADD/SUB         (S - P + A) & 0x00FF0000
+#define R_ARM_LDR_SBREL_11_0  35 // ARM ADD/SUB         (S - B + A) & 0x00000FFF
+#define R_ARM_ALU_SBREL_19_12 36 // ARM ADD/SUB         (S - B + A) & 0x000FF000
+#define R_ARM_ALU_SBREL_27_20 37 // ARM ADD/SUB         (S - B + A) & 0x0FF00000
+
+// Dynamic relocation types 
+
+// A small set of relocation types supports relocating executable ELF
+// files. They are used only in a relocation section embedded in a
+// dynamic segment (see section 4.7, Dynamic linking and
+// relocation). They cannot be used in a relocation section in a
+// re-locatable ELF file. In Figure 4-13 below:
+//
+// .S is the displacement from its statically linked virtual address
+//    of the segment containing the symbol definition.
+//
+// .P is the displacement from its statically linked virtual address
+//    of the segment containing the place to be relocated.
+//
+// .SB is the displacement of the segment pointed to by the static
+//     base (PF_ARM_SB is set in the p_flags field of this segment's
+//     program header - see 4.6, Program headers).
+
+
+// types 249 - 255 are dynamic relocation types and are only used in dynamic sections
+#define R_ARM_RXPC25    249    // ARM BLX             (.S - .P) + A
+                               //                     For calls between program segments.
+#define R_ARM_RSBREL32  250    // Word                (.S - .SB) + A
+                               //                     For an offset from SB, the static base.
+#define R_ARM_THM_RPC22 251    // Thumb BL/BLX pair   (.S - .P) + A
+                               //                     For calls between program segments.
+#define R_ARM_RREL32    252    // Word                (.S - .P) + A
+                               //                     For on offset between two segments.
+#define R_ARM_RABS32    253    // Word                .S + A
+                               //                     For the address of a location in the target segment.
+#define R_ARM_RPC24     254    // ARM B/BL            (.S - .P) + A
+                               //                     For calls between program segments.
+#define R_ARM_RBASE     255    // None                Identifies the segment being relocated by
+                               //                     the following relocation directives.
+// DYNAMIC SEGMENT
+// The dynamic segment begins with a dynamic section containing an array of structures of type:
+typedef struct Elf32_Dyn {
+  Elf32_Sword d_tag;
+  Elf32_Word d_val;
+} Elf32_Dyn;
+
+// This entry marks the end of the dynamic array. mandatory
+#define DT_NULL 0
+// Index in the string table of the name of a needed library. multiple
+#define DT_NEEDED 1
+// These entries are unused by versions 1-2 of the ARM EABI. unused
+#define DT_PLTRELSZ 2
+#define DT_PLTGOT 3
+// The offset of the hash table section in the dynamic segment. mandatory
+#define DT_HASH 4
+// The offset of the string table section in the dynamic segment. mandatory
+#define DT_STRTAB 5
+//  The offset of the symbol table section in the dynamic segment. mandatory
+#define DT_SYMTAB 6
+// The offset in the dynamic segment of an SHT_RELA relocation
+// section, Its bytesize,and the byte size of an ARMRELA-type
+// relocation entry. optional
+#define DT_RELA 7
+#define DT_RELASZ 8
+#define DT_RELAENT 9
+// The byte size of the string table section. mandatory
+#define DT_STRSZ 10
+// The byte size of an ARM symbol table entry. mandatory
+#define DT_SYMENT 11
+// These entries are unused by versions 1-2 of the ARM EABI. unused
+#define DT_INIT 12
+#define DT_FINI 13
+// The Index in the string table of the name of this shared object. mandatory
+#define DT_SONAME 14
+// Unused by the ARM EABI. unused
+#define DT_RPATH 15
+#define DT_SYMBOLIC 16
+//The offset in the dynamic segment of an SHT_REL relocation section,
+//Its bytesize, and the byte size of an ARMREL-type relocation
+//entry. optional
+#define DT_REL 17
+#define DT_RELSZ 18
+#define DT_RELENT 19
+// These entries are unused by versions 1-2 of the ARM EABI. unused
+#define DT_PLTREL 20
+#define DT_DEBUG 21
+#define DT_TEXTREL 22
+#define DT_JMPREL 23
+#define DT_BIND_NOW 24
+#define DT_INIT_ARRAY 25
+#define DT_FINI_ARRAY 26
+#define DT_INIT_ARRAYSZ 27
+#define DT_FINI_ARRAYSZ 28
+
+#define DT_VERSYM		0x6ffffff0	/* see section 3.3.3.1 in bpabi*/
+#define DT_RELCOUNT		0x6ffffffa
+#define	DT_VERDEF		0x6ffffffc	/* Address of version definition
+										table */
+#define	DT_VERDEFNUM	0x6ffffffd	/* Number of version definitions */
+#define	DT_VERNEED		0x6ffffffe	/* Address of table with needed
+										versions */
+#define	DT_VERNEEDNUM	0x6fffffff	/* Number of needed versions */
+
+// Values in this range are reserved to the ARM EABI. unused
+#define DT_LOPROC  0x70000000
+#define DT_HIPROC  0x7fffffff
+#define DT_ARM_RESERVED1   0x70000000
+/* Number of entries in the dynamic symbol table, including the initial dummy symbol. */
+#define DT_ARM_SYMTABSZ_21 0x70000000 // For RVCT 2.1
+#define DT_ARM_SYMTABSZ	   0x70000001 // The DT_ARM_SYMTABSZ tag value has been changed from RVCT2.2
+/* Holds the address of the pre-emption map for platforms that use the DLL static binding model. */
+#define DT_ARM_PREEMPTMAP  0x70000002 
+#define DT_ARM_RESERVED2   0x70000003
+#define DT_ARM_PLTGOTBASE  0x70000004
+#define DT_ARM_PLTGOTLIMIT 0x70000005
+
+// What the hash table looks like in the dynamic segment
+typedef struct Elf32_HashTable {
+  Elf32_Word nBuckets;
+  Elf32_Word nChains;
+  // Elf32_Word bucket[nBuckets];
+  // Elf32_Word chain[nChains];
+} Elf32_HashTable;
+
+
+typedef struct
+{
+  Elf32_Half	vd_version;		/* Version revision */
+  Elf32_Half	vd_flags;		/* Version information */
+  Elf32_Half	vd_ndx;			/* Version Index */
+  Elf32_Half	vd_cnt;			/* Number of associated aux entries */
+  Elf32_Word	vd_hash;		/* Version name hash value */
+  Elf32_Word	vd_aux;			/* Offset in bytes to verdaux array */
+  Elf32_Word	vd_next;		/* Offset in bytes to next verdef
+									entry */
+} Elf32_Verdef;
+
+typedef struct
+{
+  Elf32_Word	vda_name;		/* Version or dependency names */
+  Elf32_Word	vda_next;		/* Offset in bytes to next verdaux
+									entry */
+} Elf32_Verdaux;
+
+
+typedef struct
+{
+  Elf32_Half	vn_version;		/* Version of structure */
+  Elf32_Half	vn_cnt;			/* Number of associated aux entries */
+  Elf32_Word	vn_file;		/* Offset of filename for this
+									dependency */
+  Elf32_Word	vn_aux;			/* Offset in bytes to vernaux array */
+  Elf32_Word	vn_next;		/* Offset in bytes to next verneed
+					   entry */
+} Elf32_Verneed;
+
+typedef struct {
+	Elf32_Word    vna_hash;
+	Elf32_Half    vna_flags;
+	Elf32_Half    vna_other;
+	Elf32_Word    vna_name;
+	Elf32_Word    vna_next;
+} Elf32_Vernaux;
+
+
+enum ESegmentType 
+{
+	ESegmentUndefined = SHN_UNDEF,	// undefined or meaningless section/segment reference
+    ESegmentRO,						// Read Only (text) segment
+    ESegmentRW,						// Read Write (data) segment
+	ESegmentDynamic,				// Dynamic segment
+	ESegmentABS = SHN_ABS,			// Symbols defined relative to section number SHN_ABS have 
+									// absolute values and are not affected by relocation.
+	ESegmentCommon = SHN_COMMON,	// Symbols defined relative to section number SHN_ABS have 
+									// absolute values and are not affected by relocation.
+};
+
+#endif
+
+
+
+
+